LCOV - code coverage report
Current view: top level - fs/ext4 - inode.c (source / functions) Hit Total Coverage
Test: fstests of 6.5.0-rc4-xfsa @ Mon Jul 31 20:08:27 PDT 2023 Lines: 0 2695 0.0 %
Date: 2023-07-31 20:08:27 Functions: 0 118 0.0 %

          Line data    Source code
       1             : // SPDX-License-Identifier: GPL-2.0
       2             : /*
       3             :  *  linux/fs/ext4/inode.c
       4             :  *
       5             :  * Copyright (C) 1992, 1993, 1994, 1995
       6             :  * Remy Card (card@masi.ibp.fr)
       7             :  * Laboratoire MASI - Institut Blaise Pascal
       8             :  * Universite Pierre et Marie Curie (Paris VI)
       9             :  *
      10             :  *  from
      11             :  *
      12             :  *  linux/fs/minix/inode.c
      13             :  *
      14             :  *  Copyright (C) 1991, 1992  Linus Torvalds
      15             :  *
      16             :  *  64-bit file support on 64-bit platforms by Jakub Jelinek
      17             :  *      (jj@sunsite.ms.mff.cuni.cz)
      18             :  *
      19             :  *  Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
      20             :  */
      21             : 
      22             : #include <linux/fs.h>
      23             : #include <linux/mount.h>
      24             : #include <linux/time.h>
      25             : #include <linux/highuid.h>
      26             : #include <linux/pagemap.h>
      27             : #include <linux/dax.h>
      28             : #include <linux/quotaops.h>
      29             : #include <linux/string.h>
      30             : #include <linux/buffer_head.h>
      31             : #include <linux/writeback.h>
      32             : #include <linux/pagevec.h>
      33             : #include <linux/mpage.h>
      34             : #include <linux/namei.h>
      35             : #include <linux/uio.h>
      36             : #include <linux/bio.h>
      37             : #include <linux/workqueue.h>
      38             : #include <linux/kernel.h>
      39             : #include <linux/printk.h>
      40             : #include <linux/slab.h>
      41             : #include <linux/bitops.h>
      42             : #include <linux/iomap.h>
      43             : #include <linux/iversion.h>
      44             : 
      45             : #include "ext4_jbd2.h"
      46             : #include "xattr.h"
      47             : #include "acl.h"
      48             : #include "truncate.h"
      49             : 
      50             : #include <trace/events/ext4.h>
      51             : 
      52           0 : static __u32 ext4_inode_csum(struct inode *inode, struct ext4_inode *raw,
      53             :                               struct ext4_inode_info *ei)
      54             : {
      55           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
      56           0 :         __u32 csum;
      57           0 :         __u16 dummy_csum = 0;
      58           0 :         int offset = offsetof(struct ext4_inode, i_checksum_lo);
      59           0 :         unsigned int csum_size = sizeof(dummy_csum);
      60             : 
      61           0 :         csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)raw, offset);
      62           0 :         csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, csum_size);
      63           0 :         offset += csum_size;
      64           0 :         csum = ext4_chksum(sbi, csum, (__u8 *)raw + offset,
      65             :                            EXT4_GOOD_OLD_INODE_SIZE - offset);
      66             : 
      67           0 :         if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
      68           0 :                 offset = offsetof(struct ext4_inode, i_checksum_hi);
      69           0 :                 csum = ext4_chksum(sbi, csum, (__u8 *)raw +
      70             :                                    EXT4_GOOD_OLD_INODE_SIZE,
      71             :                                    offset - EXT4_GOOD_OLD_INODE_SIZE);
      72           0 :                 if (EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi)) {
      73           0 :                         csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum,
      74             :                                            csum_size);
      75           0 :                         offset += csum_size;
      76             :                 }
      77           0 :                 csum = ext4_chksum(sbi, csum, (__u8 *)raw + offset,
      78           0 :                                    EXT4_INODE_SIZE(inode->i_sb) - offset);
      79             :         }
      80             : 
      81           0 :         return csum;
      82             : }
      83             : 
      84           0 : static int ext4_inode_csum_verify(struct inode *inode, struct ext4_inode *raw,
      85             :                                   struct ext4_inode_info *ei)
      86             : {
      87           0 :         __u32 provided, calculated;
      88             : 
      89           0 :         if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
      90           0 :             cpu_to_le32(EXT4_OS_LINUX) ||
      91           0 :             !ext4_has_metadata_csum(inode->i_sb))
      92           0 :                 return 1;
      93             : 
      94           0 :         provided = le16_to_cpu(raw->i_checksum_lo);
      95           0 :         calculated = ext4_inode_csum(inode, raw, ei);
      96           0 :         if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
      97           0 :             EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
      98           0 :                 provided |= ((__u32)le16_to_cpu(raw->i_checksum_hi)) << 16;
      99             :         else
     100           0 :                 calculated &= 0xFFFF;
     101             : 
     102           0 :         return provided == calculated;
     103             : }
     104             : 
     105           0 : void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
     106             :                          struct ext4_inode_info *ei)
     107             : {
     108           0 :         __u32 csum;
     109             : 
     110           0 :         if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
     111           0 :             cpu_to_le32(EXT4_OS_LINUX) ||
     112           0 :             !ext4_has_metadata_csum(inode->i_sb))
     113           0 :                 return;
     114             : 
     115           0 :         csum = ext4_inode_csum(inode, raw, ei);
     116           0 :         raw->i_checksum_lo = cpu_to_le16(csum & 0xFFFF);
     117           0 :         if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
     118           0 :             EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
     119           0 :                 raw->i_checksum_hi = cpu_to_le16(csum >> 16);
     120             : }
     121             : 
     122           0 : static inline int ext4_begin_ordered_truncate(struct inode *inode,
     123             :                                               loff_t new_size)
     124             : {
     125           0 :         trace_ext4_begin_ordered_truncate(inode, new_size);
     126             :         /*
     127             :          * If jinode is zero, then we never opened the file for
     128             :          * writing, so there's no need to call
     129             :          * jbd2_journal_begin_ordered_truncate() since there's no
     130             :          * outstanding writes we need to flush.
     131             :          */
     132           0 :         if (!EXT4_I(inode)->jinode)
     133             :                 return 0;
     134           0 :         return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode),
     135           0 :                                                    EXT4_I(inode)->jinode,
     136             :                                                    new_size);
     137             : }
     138             : 
     139             : static int ext4_meta_trans_blocks(struct inode *inode, int lblocks,
     140             :                                   int pextents);
     141             : 
     142             : /*
     143             :  * Test whether an inode is a fast symlink.
     144             :  * A fast symlink has its symlink data stored in ext4_inode_info->i_data.
     145             :  */
     146           0 : int ext4_inode_is_fast_symlink(struct inode *inode)
     147             : {
     148           0 :         if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) {
     149           0 :                 int ea_blocks = EXT4_I(inode)->i_file_acl ?
     150           0 :                                 EXT4_CLUSTER_SIZE(inode->i_sb) >> 9 : 0;
     151             : 
     152           0 :                 if (ext4_has_inline_data(inode))
     153             :                         return 0;
     154             : 
     155           0 :                 return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
     156             :         }
     157           0 :         return S_ISLNK(inode->i_mode) && inode->i_size &&
     158             :                (inode->i_size < EXT4_N_BLOCKS * 4);
     159             : }
     160             : 
     161             : /*
     162             :  * Called at the last iput() if i_nlink is zero.
     163             :  */
     164           0 : void ext4_evict_inode(struct inode *inode)
     165             : {
     166           0 :         handle_t *handle;
     167           0 :         int err;
     168             :         /*
     169             :          * Credits for final inode cleanup and freeing:
     170             :          * sb + inode (ext4_orphan_del()), block bitmap, group descriptor
     171             :          * (xattr block freeing), bitmap, group descriptor (inode freeing)
     172             :          */
     173           0 :         int extra_credits = 6;
     174           0 :         struct ext4_xattr_inode_array *ea_inode_array = NULL;
     175           0 :         bool freeze_protected = false;
     176             : 
     177           0 :         trace_ext4_evict_inode(inode);
     178             : 
     179           0 :         if (EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)
     180           0 :                 ext4_evict_ea_inode(inode);
     181           0 :         if (inode->i_nlink) {
     182           0 :                 truncate_inode_pages_final(&inode->i_data);
     183             : 
     184           0 :                 goto no_delete;
     185             :         }
     186             : 
     187           0 :         if (is_bad_inode(inode))
     188           0 :                 goto no_delete;
     189           0 :         dquot_initialize(inode);
     190             : 
     191           0 :         if (ext4_should_order_data(inode))
     192           0 :                 ext4_begin_ordered_truncate(inode, 0);
     193           0 :         truncate_inode_pages_final(&inode->i_data);
     194             : 
     195             :         /*
     196             :          * For inodes with journalled data, transaction commit could have
     197             :          * dirtied the inode. And for inodes with dioread_nolock, unwritten
     198             :          * extents converting worker could merge extents and also have dirtied
     199             :          * the inode. Flush worker is ignoring it because of I_FREEING flag but
     200             :          * we still need to remove the inode from the writeback lists.
     201             :          */
     202           0 :         if (!list_empty_careful(&inode->i_io_list))
     203           0 :                 inode_io_list_del(inode);
     204             : 
     205             :         /*
     206             :          * Protect us against freezing - iput() caller didn't have to have any
     207             :          * protection against it. When we are in a running transaction though,
     208             :          * we are already protected against freezing and we cannot grab further
     209             :          * protection due to lock ordering constraints.
     210             :          */
     211           0 :         if (!ext4_journal_current_handle()) {
     212           0 :                 sb_start_intwrite(inode->i_sb);
     213           0 :                 freeze_protected = true;
     214             :         }
     215             : 
     216           0 :         if (!IS_NOQUOTA(inode))
     217           0 :                 extra_credits += EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb);
     218             : 
     219             :         /*
     220             :          * Block bitmap, group descriptor, and inode are accounted in both
     221             :          * ext4_blocks_for_truncate() and extra_credits. So subtract 3.
     222             :          */
     223           0 :         handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE,
     224             :                          ext4_blocks_for_truncate(inode) + extra_credits - 3);
     225           0 :         if (IS_ERR(handle)) {
     226           0 :                 ext4_std_error(inode->i_sb, PTR_ERR(handle));
     227             :                 /*
     228             :                  * If we're going to skip the normal cleanup, we still need to
     229             :                  * make sure that the in-core orphan linked list is properly
     230             :                  * cleaned up.
     231             :                  */
     232           0 :                 ext4_orphan_del(NULL, inode);
     233           0 :                 if (freeze_protected)
     234           0 :                         sb_end_intwrite(inode->i_sb);
     235           0 :                 goto no_delete;
     236             :         }
     237             : 
     238           0 :         if (IS_SYNC(inode))
     239           0 :                 ext4_handle_sync(handle);
     240             : 
     241             :         /*
     242             :          * Set inode->i_size to 0 before calling ext4_truncate(). We need
     243             :          * special handling of symlinks here because i_size is used to
     244             :          * determine whether ext4_inode_info->i_data contains symlink data or
     245             :          * block mappings. Setting i_size to 0 will remove its fast symlink
     246             :          * status. Erase i_data so that it becomes a valid empty block map.
     247             :          */
     248           0 :         if (ext4_inode_is_fast_symlink(inode))
     249           0 :                 memset(EXT4_I(inode)->i_data, 0, sizeof(EXT4_I(inode)->i_data));
     250           0 :         inode->i_size = 0;
     251           0 :         err = ext4_mark_inode_dirty(handle, inode);
     252           0 :         if (err) {
     253           0 :                 ext4_warning(inode->i_sb,
     254             :                              "couldn't mark inode dirty (err %d)", err);
     255           0 :                 goto stop_handle;
     256             :         }
     257           0 :         if (inode->i_blocks) {
     258           0 :                 err = ext4_truncate(inode);
     259           0 :                 if (err) {
     260           0 :                         ext4_error_err(inode->i_sb, -err,
     261             :                                        "couldn't truncate inode %lu (err %d)",
     262             :                                        inode->i_ino, err);
     263           0 :                         goto stop_handle;
     264             :                 }
     265             :         }
     266             : 
     267             :         /* Remove xattr references. */
     268           0 :         err = ext4_xattr_delete_inode(handle, inode, &ea_inode_array,
     269             :                                       extra_credits);
     270           0 :         if (err) {
     271           0 :                 ext4_warning(inode->i_sb, "xattr delete (err %d)", err);
     272           0 : stop_handle:
     273           0 :                 ext4_journal_stop(handle);
     274           0 :                 ext4_orphan_del(NULL, inode);
     275           0 :                 if (freeze_protected)
     276           0 :                         sb_end_intwrite(inode->i_sb);
     277           0 :                 ext4_xattr_inode_array_free(ea_inode_array);
     278           0 :                 goto no_delete;
     279             :         }
     280             : 
     281             :         /*
     282             :          * Kill off the orphan record which ext4_truncate created.
     283             :          * AKPM: I think this can be inside the above `if'.
     284             :          * Note that ext4_orphan_del() has to be able to cope with the
     285             :          * deletion of a non-existent orphan - this is because we don't
     286             :          * know if ext4_truncate() actually created an orphan record.
     287             :          * (Well, we could do this if we need to, but heck - it works)
     288             :          */
     289           0 :         ext4_orphan_del(handle, inode);
     290           0 :         EXT4_I(inode)->i_dtime       = (__u32)ktime_get_real_seconds();
     291             : 
     292             :         /*
     293             :          * One subtle ordering requirement: if anything has gone wrong
     294             :          * (transaction abort, IO errors, whatever), then we can still
     295             :          * do these next steps (the fs will already have been marked as
     296             :          * having errors), but we can't free the inode if the mark_dirty
     297             :          * fails.
     298             :          */
     299           0 :         if (ext4_mark_inode_dirty(handle, inode))
     300             :                 /* If that failed, just do the required in-core inode clear. */
     301           0 :                 ext4_clear_inode(inode);
     302             :         else
     303           0 :                 ext4_free_inode(handle, inode);
     304           0 :         ext4_journal_stop(handle);
     305           0 :         if (freeze_protected)
     306           0 :                 sb_end_intwrite(inode->i_sb);
     307           0 :         ext4_xattr_inode_array_free(ea_inode_array);
     308           0 :         return;
     309           0 : no_delete:
     310             :         /*
     311             :          * Check out some where else accidentally dirty the evicting inode,
     312             :          * which may probably cause inode use-after-free issues later.
     313             :          */
     314           0 :         WARN_ON_ONCE(!list_empty_careful(&inode->i_io_list));
     315             : 
     316           0 :         if (!list_empty(&EXT4_I(inode)->i_fc_list))
     317           0 :                 ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_NOMEM, NULL);
     318           0 :         ext4_clear_inode(inode);        /* We must guarantee clearing of inode... */
     319             : }
     320             : 
     321             : #ifdef CONFIG_QUOTA
     322           0 : qsize_t *ext4_get_reserved_space(struct inode *inode)
     323             : {
     324           0 :         return &EXT4_I(inode)->i_reserved_quota;
     325             : }
     326             : #endif
     327             : 
     328             : /*
     329             :  * Called with i_data_sem down, which is important since we can call
     330             :  * ext4_discard_preallocations() from here.
     331             :  */
     332           0 : void ext4_da_update_reserve_space(struct inode *inode,
     333             :                                         int used, int quota_claim)
     334             : {
     335           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
     336           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
     337             : 
     338           0 :         spin_lock(&ei->i_block_reservation_lock);
     339           0 :         trace_ext4_da_update_reserve_space(inode, used, quota_claim);
     340           0 :         if (unlikely(used > ei->i_reserved_data_blocks)) {
     341           0 :                 ext4_warning(inode->i_sb, "%s: ino %lu, used %d "
     342             :                          "with only %d reserved data blocks",
     343             :                          __func__, inode->i_ino, used,
     344             :                          ei->i_reserved_data_blocks);
     345           0 :                 WARN_ON(1);
     346           0 :                 used = ei->i_reserved_data_blocks;
     347             :         }
     348             : 
     349             :         /* Update per-inode reservations */
     350           0 :         ei->i_reserved_data_blocks -= used;
     351           0 :         percpu_counter_sub(&sbi->s_dirtyclusters_counter, used);
     352             : 
     353           0 :         spin_unlock(&ei->i_block_reservation_lock);
     354             : 
     355             :         /* Update quota subsystem for data blocks */
     356           0 :         if (quota_claim)
     357           0 :                 dquot_claim_block(inode, EXT4_C2B(sbi, used));
     358             :         else {
     359             :                 /*
     360             :                  * We did fallocate with an offset that is already delayed
     361             :                  * allocated. So on delayed allocated writeback we should
     362             :                  * not re-claim the quota for fallocated blocks.
     363             :                  */
     364           0 :                 dquot_release_reservation_block(inode, EXT4_C2B(sbi, used));
     365             :         }
     366             : 
     367             :         /*
     368             :          * If we have done all the pending block allocations and if
     369             :          * there aren't any writers on the inode, we can discard the
     370             :          * inode's preallocations.
     371             :          */
     372           0 :         if ((ei->i_reserved_data_blocks == 0) &&
     373             :             !inode_is_open_for_write(inode))
     374           0 :                 ext4_discard_preallocations(inode, 0);
     375           0 : }
     376             : 
     377           0 : static int __check_block_validity(struct inode *inode, const char *func,
     378             :                                 unsigned int line,
     379             :                                 struct ext4_map_blocks *map)
     380             : {
     381           0 :         if (ext4_has_feature_journal(inode->i_sb) &&
     382           0 :             (inode->i_ino ==
     383           0 :              le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_journal_inum)))
     384             :                 return 0;
     385           0 :         if (!ext4_inode_block_valid(inode, map->m_pblk, map->m_len)) {
     386           0 :                 ext4_error_inode(inode, func, line, map->m_pblk,
     387             :                                  "lblock %lu mapped to illegal pblock %llu "
     388             :                                  "(length %d)", (unsigned long) map->m_lblk,
     389             :                                  map->m_pblk, map->m_len);
     390           0 :                 return -EFSCORRUPTED;
     391             :         }
     392             :         return 0;
     393             : }
     394             : 
     395           0 : int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
     396             :                        ext4_lblk_t len)
     397             : {
     398           0 :         int ret;
     399             : 
     400           0 :         if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
     401             :                 return fscrypt_zeroout_range(inode, lblk, pblk, len);
     402             : 
     403           0 :         ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
     404           0 :         if (ret > 0)
     405             :                 ret = 0;
     406             : 
     407             :         return ret;
     408             : }
     409             : 
     410             : #define check_block_validity(inode, map)        \
     411             :         __check_block_validity((inode), __func__, __LINE__, (map))
     412             : 
     413             : #ifdef ES_AGGRESSIVE_TEST
     414             : static void ext4_map_blocks_es_recheck(handle_t *handle,
     415             :                                        struct inode *inode,
     416             :                                        struct ext4_map_blocks *es_map,
     417             :                                        struct ext4_map_blocks *map,
     418             :                                        int flags)
     419             : {
     420             :         int retval;
     421             : 
     422             :         map->m_flags = 0;
     423             :         /*
     424             :          * There is a race window that the result is not the same.
     425             :          * e.g. xfstests #223 when dioread_nolock enables.  The reason
     426             :          * is that we lookup a block mapping in extent status tree with
     427             :          * out taking i_data_sem.  So at the time the unwritten extent
     428             :          * could be converted.
     429             :          */
     430             :         down_read(&EXT4_I(inode)->i_data_sem);
     431             :         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
     432             :                 retval = ext4_ext_map_blocks(handle, inode, map, 0);
     433             :         } else {
     434             :                 retval = ext4_ind_map_blocks(handle, inode, map, 0);
     435             :         }
     436             :         up_read((&EXT4_I(inode)->i_data_sem));
     437             : 
     438             :         /*
     439             :          * We don't check m_len because extent will be collpased in status
     440             :          * tree.  So the m_len might not equal.
     441             :          */
     442             :         if (es_map->m_lblk != map->m_lblk ||
     443             :             es_map->m_flags != map->m_flags ||
     444             :             es_map->m_pblk != map->m_pblk) {
     445             :                 printk("ES cache assertion failed for inode: %lu "
     446             :                        "es_cached ex [%d/%d/%llu/%x] != "
     447             :                        "found ex [%d/%d/%llu/%x] retval %d flags %x\n",
     448             :                        inode->i_ino, es_map->m_lblk, es_map->m_len,
     449             :                        es_map->m_pblk, es_map->m_flags, map->m_lblk,
     450             :                        map->m_len, map->m_pblk, map->m_flags,
     451             :                        retval, flags);
     452             :         }
     453             : }
     454             : #endif /* ES_AGGRESSIVE_TEST */
     455             : 
     456             : /*
     457             :  * The ext4_map_blocks() function tries to look up the requested blocks,
     458             :  * and returns if the blocks are already mapped.
     459             :  *
     460             :  * Otherwise it takes the write lock of the i_data_sem and allocate blocks
     461             :  * and store the allocated blocks in the result buffer head and mark it
     462             :  * mapped.
     463             :  *
     464             :  * If file type is extents based, it will call ext4_ext_map_blocks(),
     465             :  * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
     466             :  * based files
     467             :  *
     468             :  * On success, it returns the number of blocks being mapped or allocated.  if
     469             :  * create==0 and the blocks are pre-allocated and unwritten, the resulting @map
     470             :  * is marked as unwritten. If the create == 1, it will mark @map as mapped.
     471             :  *
     472             :  * It returns 0 if plain look up failed (blocks have not been allocated), in
     473             :  * that case, @map is returned as unmapped but we still do fill map->m_len to
     474             :  * indicate the length of a hole starting at map->m_lblk.
     475             :  *
     476             :  * It returns the error in case of allocation failure.
     477             :  */
     478           0 : int ext4_map_blocks(handle_t *handle, struct inode *inode,
     479             :                     struct ext4_map_blocks *map, int flags)
     480             : {
     481           0 :         struct extent_status es;
     482           0 :         int retval;
     483           0 :         int ret = 0;
     484             : #ifdef ES_AGGRESSIVE_TEST
     485             :         struct ext4_map_blocks orig_map;
     486             : 
     487             :         memcpy(&orig_map, map, sizeof(*map));
     488             : #endif
     489             : 
     490           0 :         map->m_flags = 0;
     491           0 :         ext_debug(inode, "flag 0x%x, max_blocks %u, logical block %lu\n",
     492             :                   flags, map->m_len, (unsigned long) map->m_lblk);
     493             : 
     494             :         /*
     495             :          * ext4_map_blocks returns an int, and m_len is an unsigned int
     496             :          */
     497           0 :         if (unlikely(map->m_len > INT_MAX))
     498           0 :                 map->m_len = INT_MAX;
     499             : 
     500             :         /* We can handle the block number less than EXT_MAX_BLOCKS */
     501           0 :         if (unlikely(map->m_lblk >= EXT_MAX_BLOCKS))
     502             :                 return -EFSCORRUPTED;
     503             : 
     504             :         /* Lookup extent status tree firstly */
     505           0 :         if (!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY) &&
     506           0 :             ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) {
     507           0 :                 if (ext4_es_is_written(&es) || ext4_es_is_unwritten(&es)) {
     508           0 :                         map->m_pblk = ext4_es_pblock(&es) +
     509           0 :                                         map->m_lblk - es.es_lblk;
     510           0 :                         map->m_flags |= ext4_es_is_written(&es) ?
     511           0 :                                         EXT4_MAP_MAPPED : EXT4_MAP_UNWRITTEN;
     512           0 :                         retval = es.es_len - (map->m_lblk - es.es_lblk);
     513           0 :                         if (retval > map->m_len)
     514             :                                 retval = map->m_len;
     515           0 :                         map->m_len = retval;
     516           0 :                 } else if (ext4_es_is_delayed(&es) || ext4_es_is_hole(&es)) {
     517           0 :                         map->m_pblk = 0;
     518           0 :                         retval = es.es_len - (map->m_lblk - es.es_lblk);
     519           0 :                         if (retval > map->m_len)
     520             :                                 retval = map->m_len;
     521           0 :                         map->m_len = retval;
     522           0 :                         retval = 0;
     523             :                 } else {
     524           0 :                         BUG();
     525             :                 }
     526             : 
     527           0 :                 if (flags & EXT4_GET_BLOCKS_CACHED_NOWAIT)
     528             :                         return retval;
     529             : #ifdef ES_AGGRESSIVE_TEST
     530             :                 ext4_map_blocks_es_recheck(handle, inode, map,
     531             :                                            &orig_map, flags);
     532             : #endif
     533           0 :                 goto found;
     534             :         }
     535             :         /*
     536             :          * In the query cache no-wait mode, nothing we can do more if we
     537             :          * cannot find extent in the cache.
     538             :          */
     539           0 :         if (flags & EXT4_GET_BLOCKS_CACHED_NOWAIT)
     540             :                 return 0;
     541             : 
     542             :         /*
     543             :          * Try to see if we can get the block without requesting a new
     544             :          * file system block.
     545             :          */
     546           0 :         down_read(&EXT4_I(inode)->i_data_sem);
     547           0 :         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
     548           0 :                 retval = ext4_ext_map_blocks(handle, inode, map, 0);
     549             :         } else {
     550           0 :                 retval = ext4_ind_map_blocks(handle, inode, map, 0);
     551             :         }
     552           0 :         if (retval > 0) {
     553           0 :                 unsigned int status;
     554             : 
     555           0 :                 if (unlikely(retval != map->m_len)) {
     556           0 :                         ext4_warning(inode->i_sb,
     557             :                                      "ES len assertion failed for inode "
     558             :                                      "%lu: retval %d != map->m_len %d",
     559             :                                      inode->i_ino, retval, map->m_len);
     560           0 :                         WARN_ON(1);
     561             :                 }
     562             : 
     563           0 :                 status = map->m_flags & EXT4_MAP_UNWRITTEN ?
     564           0 :                                 EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
     565           0 :                 if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
     566           0 :                     !(status & EXTENT_STATUS_WRITTEN) &&
     567           0 :                     ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk,
     568           0 :                                        map->m_lblk + map->m_len - 1))
     569           0 :                         status |= EXTENT_STATUS_DELAYED;
     570           0 :                 ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
     571             :                                       map->m_pblk, status);
     572             :         }
     573           0 :         up_read((&EXT4_I(inode)->i_data_sem));
     574             : 
     575           0 : found:
     576           0 :         if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
     577           0 :                 ret = check_block_validity(inode, map);
     578           0 :                 if (ret != 0)
     579             :                         return ret;
     580             :         }
     581             : 
     582             :         /* If it is only a block(s) look up */
     583           0 :         if ((flags & EXT4_GET_BLOCKS_CREATE) == 0)
     584             :                 return retval;
     585             : 
     586             :         /*
     587             :          * Returns if the blocks have already allocated
     588             :          *
     589             :          * Note that if blocks have been preallocated
     590             :          * ext4_ext_get_block() returns the create = 0
     591             :          * with buffer head unmapped.
     592             :          */
     593           0 :         if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED)
     594             :                 /*
     595             :                  * If we need to convert extent to unwritten
     596             :                  * we continue and do the actual work in
     597             :                  * ext4_ext_map_blocks()
     598             :                  */
     599           0 :                 if (!(flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN))
     600             :                         return retval;
     601             : 
     602             :         /*
     603             :          * Here we clear m_flags because after allocating an new extent,
     604             :          * it will be set again.
     605             :          */
     606           0 :         map->m_flags &= ~EXT4_MAP_FLAGS;
     607             : 
     608             :         /*
     609             :          * New blocks allocate and/or writing to unwritten extent
     610             :          * will possibly result in updating i_data, so we take
     611             :          * the write lock of i_data_sem, and call get_block()
     612             :          * with create == 1 flag.
     613             :          */
     614           0 :         down_write(&EXT4_I(inode)->i_data_sem);
     615             : 
     616             :         /*
     617             :          * We need to check for EXT4 here because migrate
     618             :          * could have changed the inode type in between
     619             :          */
     620           0 :         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
     621           0 :                 retval = ext4_ext_map_blocks(handle, inode, map, flags);
     622             :         } else {
     623           0 :                 retval = ext4_ind_map_blocks(handle, inode, map, flags);
     624             : 
     625           0 :                 if (retval > 0 && map->m_flags & EXT4_MAP_NEW) {
     626             :                         /*
     627             :                          * We allocated new blocks which will result in
     628             :                          * i_data's format changing.  Force the migrate
     629             :                          * to fail by clearing migrate flags
     630             :                          */
     631           0 :                         ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
     632             :                 }
     633             :         }
     634             : 
     635           0 :         if (retval > 0) {
     636           0 :                 unsigned int status;
     637             : 
     638           0 :                 if (unlikely(retval != map->m_len)) {
     639           0 :                         ext4_warning(inode->i_sb,
     640             :                                      "ES len assertion failed for inode "
     641             :                                      "%lu: retval %d != map->m_len %d",
     642             :                                      inode->i_ino, retval, map->m_len);
     643           0 :                         WARN_ON(1);
     644             :                 }
     645             : 
     646             :                 /*
     647             :                  * We have to zeroout blocks before inserting them into extent
     648             :                  * status tree. Otherwise someone could look them up there and
     649             :                  * use them before they are really zeroed. We also have to
     650             :                  * unmap metadata before zeroing as otherwise writeback can
     651             :                  * overwrite zeros with stale data from block device.
     652             :                  */
     653           0 :                 if (flags & EXT4_GET_BLOCKS_ZERO &&
     654           0 :                     map->m_flags & EXT4_MAP_MAPPED &&
     655             :                     map->m_flags & EXT4_MAP_NEW) {
     656           0 :                         ret = ext4_issue_zeroout(inode, map->m_lblk,
     657             :                                                  map->m_pblk, map->m_len);
     658           0 :                         if (ret) {
     659           0 :                                 retval = ret;
     660           0 :                                 goto out_sem;
     661             :                         }
     662             :                 }
     663             : 
     664             :                 /*
     665             :                  * If the extent has been zeroed out, we don't need to update
     666             :                  * extent status tree.
     667             :                  */
     668           0 :                 if ((flags & EXT4_GET_BLOCKS_PRE_IO) &&
     669           0 :                     ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) {
     670           0 :                         if (ext4_es_is_written(&es))
     671           0 :                                 goto out_sem;
     672             :                 }
     673           0 :                 status = map->m_flags & EXT4_MAP_UNWRITTEN ?
     674           0 :                                 EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
     675           0 :                 if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
     676           0 :                     !(status & EXTENT_STATUS_WRITTEN) &&
     677           0 :                     ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk,
     678           0 :                                        map->m_lblk + map->m_len - 1))
     679           0 :                         status |= EXTENT_STATUS_DELAYED;
     680           0 :                 ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
     681             :                                       map->m_pblk, status);
     682             :         }
     683             : 
     684           0 : out_sem:
     685           0 :         up_write((&EXT4_I(inode)->i_data_sem));
     686           0 :         if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
     687           0 :                 ret = check_block_validity(inode, map);
     688           0 :                 if (ret != 0)
     689             :                         return ret;
     690             : 
     691             :                 /*
     692             :                  * Inodes with freshly allocated blocks where contents will be
     693             :                  * visible after transaction commit must be on transaction's
     694             :                  * ordered data list.
     695             :                  */
     696           0 :                 if (map->m_flags & EXT4_MAP_NEW &&
     697           0 :                     !(map->m_flags & EXT4_MAP_UNWRITTEN) &&
     698           0 :                     !(flags & EXT4_GET_BLOCKS_ZERO) &&
     699           0 :                     !ext4_is_quota_file(inode) &&
     700             :                     ext4_should_order_data(inode)) {
     701           0 :                         loff_t start_byte =
     702           0 :                                 (loff_t)map->m_lblk << inode->i_blkbits;
     703           0 :                         loff_t length = (loff_t)map->m_len << inode->i_blkbits;
     704             : 
     705           0 :                         if (flags & EXT4_GET_BLOCKS_IO_SUBMIT)
     706           0 :                                 ret = ext4_jbd2_inode_add_wait(handle, inode,
     707             :                                                 start_byte, length);
     708             :                         else
     709           0 :                                 ret = ext4_jbd2_inode_add_write(handle, inode,
     710             :                                                 start_byte, length);
     711           0 :                         if (ret)
     712             :                                 return ret;
     713             :                 }
     714             :         }
     715           0 :         if (retval > 0 && (map->m_flags & EXT4_MAP_UNWRITTEN ||
     716             :                                 map->m_flags & EXT4_MAP_MAPPED))
     717           0 :                 ext4_fc_track_range(handle, inode, map->m_lblk,
     718           0 :                                         map->m_lblk + map->m_len - 1);
     719             :         if (retval < 0)
     720             :                 ext_debug(inode, "failed with err %d\n", retval);
     721             :         return retval;
     722             : }
     723             : 
     724             : /*
     725             :  * Update EXT4_MAP_FLAGS in bh->b_state. For buffer heads attached to pages
     726             :  * we have to be careful as someone else may be manipulating b_state as well.
     727             :  */
     728           0 : static void ext4_update_bh_state(struct buffer_head *bh, unsigned long flags)
     729             : {
     730           0 :         unsigned long old_state;
     731           0 :         unsigned long new_state;
     732             : 
     733           0 :         flags &= EXT4_MAP_FLAGS;
     734             : 
     735             :         /* Dummy buffer_head? Set non-atomically. */
     736           0 :         if (!bh->b_page) {
     737           0 :                 bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | flags;
     738           0 :                 return;
     739             :         }
     740             :         /*
     741             :          * Someone else may be modifying b_state. Be careful! This is ugly but
     742             :          * once we get rid of using bh as a container for mapping information
     743             :          * to pass to / from get_block functions, this can go away.
     744             :          */
     745           0 :         old_state = READ_ONCE(bh->b_state);
     746           0 :         do {
     747           0 :                 new_state = (old_state & ~EXT4_MAP_FLAGS) | flags;
     748           0 :         } while (unlikely(!try_cmpxchg(&bh->b_state, &old_state, new_state)));
     749             : }
     750             : 
     751           0 : static int _ext4_get_block(struct inode *inode, sector_t iblock,
     752             :                            struct buffer_head *bh, int flags)
     753             : {
     754           0 :         struct ext4_map_blocks map;
     755           0 :         int ret = 0;
     756             : 
     757           0 :         if (ext4_has_inline_data(inode))
     758             :                 return -ERANGE;
     759             : 
     760           0 :         map.m_lblk = iblock;
     761           0 :         map.m_len = bh->b_size >> inode->i_blkbits;
     762             : 
     763           0 :         ret = ext4_map_blocks(ext4_journal_current_handle(), inode, &map,
     764             :                               flags);
     765           0 :         if (ret > 0) {
     766           0 :                 map_bh(bh, inode->i_sb, map.m_pblk);
     767           0 :                 ext4_update_bh_state(bh, map.m_flags);
     768           0 :                 bh->b_size = inode->i_sb->s_blocksize * map.m_len;
     769           0 :                 ret = 0;
     770           0 :         } else if (ret == 0) {
     771             :                 /* hole case, need to fill in bh->b_size */
     772           0 :                 bh->b_size = inode->i_sb->s_blocksize * map.m_len;
     773             :         }
     774             :         return ret;
     775             : }
     776             : 
     777           0 : int ext4_get_block(struct inode *inode, sector_t iblock,
     778             :                    struct buffer_head *bh, int create)
     779             : {
     780           0 :         return _ext4_get_block(inode, iblock, bh,
     781             :                                create ? EXT4_GET_BLOCKS_CREATE : 0);
     782             : }
     783             : 
     784             : /*
     785             :  * Get block function used when preparing for buffered write if we require
     786             :  * creating an unwritten extent if blocks haven't been allocated.  The extent
     787             :  * will be converted to written after the IO is complete.
     788             :  */
     789           0 : int ext4_get_block_unwritten(struct inode *inode, sector_t iblock,
     790             :                              struct buffer_head *bh_result, int create)
     791             : {
     792           0 :         ext4_debug("ext4_get_block_unwritten: inode %lu, create flag %d\n",
     793             :                    inode->i_ino, create);
     794           0 :         return _ext4_get_block(inode, iblock, bh_result,
     795             :                                EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT);
     796             : }
     797             : 
     798             : /* Maximum number of blocks we map for direct IO at once. */
     799             : #define DIO_MAX_BLOCKS 4096
     800             : 
     801             : /*
     802             :  * `handle' can be NULL if create is zero
     803             :  */
     804           0 : struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
     805             :                                 ext4_lblk_t block, int map_flags)
     806             : {
     807           0 :         struct ext4_map_blocks map;
     808           0 :         struct buffer_head *bh;
     809           0 :         int create = map_flags & EXT4_GET_BLOCKS_CREATE;
     810           0 :         bool nowait = map_flags & EXT4_GET_BLOCKS_CACHED_NOWAIT;
     811           0 :         int err;
     812             : 
     813           0 :         ASSERT((EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
     814             :                     || handle != NULL || create == 0);
     815           0 :         ASSERT(create == 0 || !nowait);
     816             : 
     817           0 :         map.m_lblk = block;
     818           0 :         map.m_len = 1;
     819           0 :         err = ext4_map_blocks(handle, inode, &map, map_flags);
     820             : 
     821           0 :         if (err == 0)
     822           0 :                 return create ? ERR_PTR(-ENOSPC) : NULL;
     823           0 :         if (err < 0)
     824           0 :                 return ERR_PTR(err);
     825             : 
     826           0 :         if (nowait)
     827           0 :                 return sb_find_get_block(inode->i_sb, map.m_pblk);
     828             : 
     829           0 :         bh = sb_getblk(inode->i_sb, map.m_pblk);
     830           0 :         if (unlikely(!bh))
     831             :                 return ERR_PTR(-ENOMEM);
     832           0 :         if (map.m_flags & EXT4_MAP_NEW) {
     833           0 :                 ASSERT(create != 0);
     834           0 :                 ASSERT((EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
     835             :                             || (handle != NULL));
     836             : 
     837             :                 /*
     838             :                  * Now that we do not always journal data, we should
     839             :                  * keep in mind whether this should always journal the
     840             :                  * new buffer as metadata.  For now, regular file
     841             :                  * writes use ext4_get_block instead, so it's not a
     842             :                  * problem.
     843             :                  */
     844           0 :                 lock_buffer(bh);
     845           0 :                 BUFFER_TRACE(bh, "call get_create_access");
     846           0 :                 err = ext4_journal_get_create_access(handle, inode->i_sb, bh,
     847             :                                                      EXT4_JTR_NONE);
     848           0 :                 if (unlikely(err)) {
     849           0 :                         unlock_buffer(bh);
     850           0 :                         goto errout;
     851             :                 }
     852           0 :                 if (!buffer_uptodate(bh)) {
     853           0 :                         memset(bh->b_data, 0, inode->i_sb->s_blocksize);
     854           0 :                         set_buffer_uptodate(bh);
     855             :                 }
     856           0 :                 unlock_buffer(bh);
     857           0 :                 BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
     858           0 :                 err = ext4_handle_dirty_metadata(handle, inode, bh);
     859           0 :                 if (unlikely(err))
     860           0 :                         goto errout;
     861             :         } else
     862             :                 BUFFER_TRACE(bh, "not a new buffer");
     863             :         return bh;
     864           0 : errout:
     865           0 :         brelse(bh);
     866           0 :         return ERR_PTR(err);
     867             : }
     868             : 
     869           0 : struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
     870             :                                ext4_lblk_t block, int map_flags)
     871             : {
     872           0 :         struct buffer_head *bh;
     873           0 :         int ret;
     874             : 
     875           0 :         bh = ext4_getblk(handle, inode, block, map_flags);
     876           0 :         if (IS_ERR(bh))
     877             :                 return bh;
     878           0 :         if (!bh || ext4_buffer_uptodate(bh))
     879           0 :                 return bh;
     880             : 
     881           0 :         ret = ext4_read_bh_lock(bh, REQ_META | REQ_PRIO, true);
     882           0 :         if (ret) {
     883           0 :                 put_bh(bh);
     884           0 :                 return ERR_PTR(ret);
     885             :         }
     886             :         return bh;
     887             : }
     888             : 
     889             : /* Read a contiguous batch of blocks. */
     890           0 : int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
     891             :                      bool wait, struct buffer_head **bhs)
     892             : {
     893           0 :         int i, err;
     894             : 
     895           0 :         for (i = 0; i < bh_count; i++) {
     896           0 :                 bhs[i] = ext4_getblk(NULL, inode, block + i, 0 /* map_flags */);
     897           0 :                 if (IS_ERR(bhs[i])) {
     898           0 :                         err = PTR_ERR(bhs[i]);
     899           0 :                         bh_count = i;
     900           0 :                         goto out_brelse;
     901             :                 }
     902             :         }
     903             : 
     904           0 :         for (i = 0; i < bh_count; i++)
     905             :                 /* Note that NULL bhs[i] is valid because of holes. */
     906           0 :                 if (bhs[i] && !ext4_buffer_uptodate(bhs[i]))
     907           0 :                         ext4_read_bh_lock(bhs[i], REQ_META | REQ_PRIO, false);
     908             : 
     909           0 :         if (!wait)
     910             :                 return 0;
     911             : 
     912           0 :         for (i = 0; i < bh_count; i++)
     913           0 :                 if (bhs[i])
     914           0 :                         wait_on_buffer(bhs[i]);
     915             : 
     916           0 :         for (i = 0; i < bh_count; i++) {
     917           0 :                 if (bhs[i] && !buffer_uptodate(bhs[i])) {
     918           0 :                         err = -EIO;
     919           0 :                         goto out_brelse;
     920             :                 }
     921             :         }
     922             :         return 0;
     923             : 
     924           0 : out_brelse:
     925           0 :         for (i = 0; i < bh_count; i++) {
     926           0 :                 brelse(bhs[i]);
     927           0 :                 bhs[i] = NULL;
     928             :         }
     929             :         return err;
     930             : }
     931             : 
     932           0 : int ext4_walk_page_buffers(handle_t *handle, struct inode *inode,
     933             :                            struct buffer_head *head,
     934             :                            unsigned from,
     935             :                            unsigned to,
     936             :                            int *partial,
     937             :                            int (*fn)(handle_t *handle, struct inode *inode,
     938             :                                      struct buffer_head *bh))
     939             : {
     940           0 :         struct buffer_head *bh;
     941           0 :         unsigned block_start, block_end;
     942           0 :         unsigned blocksize = head->b_size;
     943           0 :         int err, ret = 0;
     944           0 :         struct buffer_head *next;
     945             : 
     946           0 :         for (bh = head, block_start = 0;
     947           0 :              ret == 0 && (bh != head || !block_start);
     948             :              block_start = block_end, bh = next) {
     949           0 :                 next = bh->b_this_page;
     950           0 :                 block_end = block_start + blocksize;
     951           0 :                 if (block_end <= from || block_start >= to) {
     952           0 :                         if (partial && !buffer_uptodate(bh))
     953           0 :                                 *partial = 1;
     954           0 :                         continue;
     955             :                 }
     956           0 :                 err = (*fn)(handle, inode, bh);
     957           0 :                 if (!ret)
     958           0 :                         ret = err;
     959             :         }
     960           0 :         return ret;
     961             : }
     962             : 
     963             : /*
     964             :  * Helper for handling dirtying of journalled data. We also mark the folio as
     965             :  * dirty so that writeback code knows about this page (and inode) contains
     966             :  * dirty data. ext4_writepages() then commits appropriate transaction to
     967             :  * make data stable.
     968             :  */
     969           0 : static int ext4_dirty_journalled_data(handle_t *handle, struct buffer_head *bh)
     970             : {
     971           0 :         folio_mark_dirty(bh->b_folio);
     972           0 :         return ext4_handle_dirty_metadata(handle, NULL, bh);
     973             : }
     974             : 
     975           0 : int do_journal_get_write_access(handle_t *handle, struct inode *inode,
     976             :                                 struct buffer_head *bh)
     977             : {
     978           0 :         int dirty = buffer_dirty(bh);
     979           0 :         int ret;
     980             : 
     981           0 :         if (!buffer_mapped(bh) || buffer_freed(bh))
     982             :                 return 0;
     983             :         /*
     984             :          * __block_write_begin() could have dirtied some buffers. Clean
     985             :          * the dirty bit as jbd2_journal_get_write_access() could complain
     986             :          * otherwise about fs integrity issues. Setting of the dirty bit
     987             :          * by __block_write_begin() isn't a real problem here as we clear
     988             :          * the bit before releasing a page lock and thus writeback cannot
     989             :          * ever write the buffer.
     990             :          */
     991           0 :         if (dirty)
     992           0 :                 clear_buffer_dirty(bh);
     993           0 :         BUFFER_TRACE(bh, "get write access");
     994           0 :         ret = ext4_journal_get_write_access(handle, inode->i_sb, bh,
     995             :                                             EXT4_JTR_NONE);
     996           0 :         if (!ret && dirty)
     997           0 :                 ret = ext4_dirty_journalled_data(handle, bh);
     998             :         return ret;
     999             : }
    1000             : 
    1001             : #ifdef CONFIG_FS_ENCRYPTION
    1002             : static int ext4_block_write_begin(struct folio *folio, loff_t pos, unsigned len,
    1003             :                                   get_block_t *get_block)
    1004             : {
    1005             :         unsigned from = pos & (PAGE_SIZE - 1);
    1006             :         unsigned to = from + len;
    1007             :         struct inode *inode = folio->mapping->host;
    1008             :         unsigned block_start, block_end;
    1009             :         sector_t block;
    1010             :         int err = 0;
    1011             :         unsigned blocksize = inode->i_sb->s_blocksize;
    1012             :         unsigned bbits;
    1013             :         struct buffer_head *bh, *head, *wait[2];
    1014             :         int nr_wait = 0;
    1015             :         int i;
    1016             : 
    1017             :         BUG_ON(!folio_test_locked(folio));
    1018             :         BUG_ON(from > PAGE_SIZE);
    1019             :         BUG_ON(to > PAGE_SIZE);
    1020             :         BUG_ON(from > to);
    1021             : 
    1022             :         head = folio_buffers(folio);
    1023             :         if (!head) {
    1024             :                 create_empty_buffers(&folio->page, blocksize, 0);
    1025             :                 head = folio_buffers(folio);
    1026             :         }
    1027             :         bbits = ilog2(blocksize);
    1028             :         block = (sector_t)folio->index << (PAGE_SHIFT - bbits);
    1029             : 
    1030             :         for (bh = head, block_start = 0; bh != head || !block_start;
    1031             :             block++, block_start = block_end, bh = bh->b_this_page) {
    1032             :                 block_end = block_start + blocksize;
    1033             :                 if (block_end <= from || block_start >= to) {
    1034             :                         if (folio_test_uptodate(folio)) {
    1035             :                                 set_buffer_uptodate(bh);
    1036             :                         }
    1037             :                         continue;
    1038             :                 }
    1039             :                 if (buffer_new(bh))
    1040             :                         clear_buffer_new(bh);
    1041             :                 if (!buffer_mapped(bh)) {
    1042             :                         WARN_ON(bh->b_size != blocksize);
    1043             :                         err = get_block(inode, block, bh, 1);
    1044             :                         if (err)
    1045             :                                 break;
    1046             :                         if (buffer_new(bh)) {
    1047             :                                 if (folio_test_uptodate(folio)) {
    1048             :                                         clear_buffer_new(bh);
    1049             :                                         set_buffer_uptodate(bh);
    1050             :                                         mark_buffer_dirty(bh);
    1051             :                                         continue;
    1052             :                                 }
    1053             :                                 if (block_end > to || block_start < from)
    1054             :                                         folio_zero_segments(folio, to,
    1055             :                                                             block_end,
    1056             :                                                             block_start, from);
    1057             :                                 continue;
    1058             :                         }
    1059             :                 }
    1060             :                 if (folio_test_uptodate(folio)) {
    1061             :                         set_buffer_uptodate(bh);
    1062             :                         continue;
    1063             :                 }
    1064             :                 if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
    1065             :                     !buffer_unwritten(bh) &&
    1066             :                     (block_start < from || block_end > to)) {
    1067             :                         ext4_read_bh_lock(bh, 0, false);
    1068             :                         wait[nr_wait++] = bh;
    1069             :                 }
    1070             :         }
    1071             :         /*
    1072             :          * If we issued read requests, let them complete.
    1073             :          */
    1074             :         for (i = 0; i < nr_wait; i++) {
    1075             :                 wait_on_buffer(wait[i]);
    1076             :                 if (!buffer_uptodate(wait[i]))
    1077             :                         err = -EIO;
    1078             :         }
    1079             :         if (unlikely(err)) {
    1080             :                 folio_zero_new_buffers(folio, from, to);
    1081             :         } else if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
    1082             :                 for (i = 0; i < nr_wait; i++) {
    1083             :                         int err2;
    1084             : 
    1085             :                         err2 = fscrypt_decrypt_pagecache_blocks(folio,
    1086             :                                                 blocksize, bh_offset(wait[i]));
    1087             :                         if (err2) {
    1088             :                                 clear_buffer_uptodate(wait[i]);
    1089             :                                 err = err2;
    1090             :                         }
    1091             :                 }
    1092             :         }
    1093             : 
    1094             :         return err;
    1095             : }
    1096             : #endif
    1097             : 
    1098             : /*
    1099             :  * To preserve ordering, it is essential that the hole instantiation and
    1100             :  * the data write be encapsulated in a single transaction.  We cannot
    1101             :  * close off a transaction and start a new one between the ext4_get_block()
    1102             :  * and the ext4_write_end().  So doing the jbd2_journal_start at the start of
    1103             :  * ext4_write_begin() is the right place.
    1104             :  */
    1105           0 : static int ext4_write_begin(struct file *file, struct address_space *mapping,
    1106             :                             loff_t pos, unsigned len,
    1107             :                             struct page **pagep, void **fsdata)
    1108             : {
    1109           0 :         struct inode *inode = mapping->host;
    1110           0 :         int ret, needed_blocks;
    1111           0 :         handle_t *handle;
    1112           0 :         int retries = 0;
    1113           0 :         struct folio *folio;
    1114           0 :         pgoff_t index;
    1115           0 :         unsigned from, to;
    1116             : 
    1117           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
    1118             :                 return -EIO;
    1119             : 
    1120           0 :         trace_ext4_write_begin(inode, pos, len);
    1121             :         /*
    1122             :          * Reserve one block more for addition to orphan list in case
    1123             :          * we allocate blocks but write fails for some reason
    1124             :          */
    1125           0 :         needed_blocks = ext4_writepage_trans_blocks(inode) + 1;
    1126           0 :         index = pos >> PAGE_SHIFT;
    1127           0 :         from = pos & (PAGE_SIZE - 1);
    1128           0 :         to = from + len;
    1129             : 
    1130           0 :         if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
    1131           0 :                 ret = ext4_try_to_write_inline_data(mapping, inode, pos, len,
    1132             :                                                     pagep);
    1133           0 :                 if (ret < 0)
    1134             :                         return ret;
    1135           0 :                 if (ret == 1)
    1136             :                         return 0;
    1137             :         }
    1138             : 
    1139             :         /*
    1140             :          * __filemap_get_folio() can take a long time if the
    1141             :          * system is thrashing due to memory pressure, or if the folio
    1142             :          * is being written back.  So grab it first before we start
    1143             :          * the transaction handle.  This also allows us to allocate
    1144             :          * the folio (if needed) without using GFP_NOFS.
    1145             :          */
    1146           0 : retry_grab:
    1147           0 :         folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
    1148             :                                         mapping_gfp_mask(mapping));
    1149           0 :         if (IS_ERR(folio))
    1150           0 :                 return PTR_ERR(folio);
    1151             :         /*
    1152             :          * The same as page allocation, we prealloc buffer heads before
    1153             :          * starting the handle.
    1154             :          */
    1155           0 :         if (!folio_buffers(folio))
    1156           0 :                 create_empty_buffers(&folio->page, inode->i_sb->s_blocksize, 0);
    1157             : 
    1158           0 :         folio_unlock(folio);
    1159             : 
    1160           0 : retry_journal:
    1161           0 :         handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
    1162           0 :         if (IS_ERR(handle)) {
    1163           0 :                 folio_put(folio);
    1164           0 :                 return PTR_ERR(handle);
    1165             :         }
    1166             : 
    1167           0 :         folio_lock(folio);
    1168           0 :         if (folio->mapping != mapping) {
    1169             :                 /* The folio got truncated from under us */
    1170           0 :                 folio_unlock(folio);
    1171           0 :                 folio_put(folio);
    1172           0 :                 ext4_journal_stop(handle);
    1173           0 :                 goto retry_grab;
    1174             :         }
    1175             :         /* In case writeback began while the folio was unlocked */
    1176           0 :         folio_wait_stable(folio);
    1177             : 
    1178             : #ifdef CONFIG_FS_ENCRYPTION
    1179             :         if (ext4_should_dioread_nolock(inode))
    1180             :                 ret = ext4_block_write_begin(folio, pos, len,
    1181             :                                              ext4_get_block_unwritten);
    1182             :         else
    1183             :                 ret = ext4_block_write_begin(folio, pos, len, ext4_get_block);
    1184             : #else
    1185           0 :         if (ext4_should_dioread_nolock(inode))
    1186           0 :                 ret = __block_write_begin(&folio->page, pos, len,
    1187             :                                           ext4_get_block_unwritten);
    1188             :         else
    1189           0 :                 ret = __block_write_begin(&folio->page, pos, len, ext4_get_block);
    1190             : #endif
    1191           0 :         if (!ret && ext4_should_journal_data(inode)) {
    1192           0 :                 ret = ext4_walk_page_buffers(handle, inode,
    1193             :                                              folio_buffers(folio), from, to,
    1194             :                                              NULL, do_journal_get_write_access);
    1195             :         }
    1196             : 
    1197           0 :         if (ret) {
    1198           0 :                 bool extended = (pos + len > inode->i_size) &&
    1199             :                                 !ext4_verity_in_progress(inode);
    1200             : 
    1201           0 :                 folio_unlock(folio);
    1202             :                 /*
    1203             :                  * __block_write_begin may have instantiated a few blocks
    1204             :                  * outside i_size.  Trim these off again. Don't need
    1205             :                  * i_size_read because we hold i_rwsem.
    1206             :                  *
    1207             :                  * Add inode to orphan list in case we crash before
    1208             :                  * truncate finishes
    1209             :                  */
    1210           0 :                 if (extended && ext4_can_truncate(inode))
    1211           0 :                         ext4_orphan_add(handle, inode);
    1212             : 
    1213           0 :                 ext4_journal_stop(handle);
    1214           0 :                 if (extended) {
    1215           0 :                         ext4_truncate_failed_write(inode);
    1216             :                         /*
    1217             :                          * If truncate failed early the inode might
    1218             :                          * still be on the orphan list; we need to
    1219             :                          * make sure the inode is removed from the
    1220             :                          * orphan list in that case.
    1221             :                          */
    1222           0 :                         if (inode->i_nlink)
    1223           0 :                                 ext4_orphan_del(NULL, inode);
    1224             :                 }
    1225             : 
    1226           0 :                 if (ret == -ENOSPC &&
    1227           0 :                     ext4_should_retry_alloc(inode->i_sb, &retries))
    1228           0 :                         goto retry_journal;
    1229           0 :                 folio_put(folio);
    1230           0 :                 return ret;
    1231             :         }
    1232           0 :         *pagep = &folio->page;
    1233           0 :         return ret;
    1234             : }
    1235             : 
    1236             : /* For write_end() in data=journal mode */
    1237           0 : static int write_end_fn(handle_t *handle, struct inode *inode,
    1238             :                         struct buffer_head *bh)
    1239             : {
    1240           0 :         int ret;
    1241           0 :         if (!buffer_mapped(bh) || buffer_freed(bh))
    1242             :                 return 0;
    1243           0 :         set_buffer_uptodate(bh);
    1244           0 :         ret = ext4_dirty_journalled_data(handle, bh);
    1245           0 :         clear_buffer_meta(bh);
    1246           0 :         clear_buffer_prio(bh);
    1247             :         return ret;
    1248             : }
    1249             : 
    1250             : /*
    1251             :  * We need to pick up the new inode size which generic_commit_write gave us
    1252             :  * `file' can be NULL - eg, when called from page_symlink().
    1253             :  *
    1254             :  * ext4 never places buffers on inode->i_mapping->private_list.  metadata
    1255             :  * buffers are managed internally.
    1256             :  */
    1257           0 : static int ext4_write_end(struct file *file,
    1258             :                           struct address_space *mapping,
    1259             :                           loff_t pos, unsigned len, unsigned copied,
    1260             :                           struct page *page, void *fsdata)
    1261             : {
    1262           0 :         struct folio *folio = page_folio(page);
    1263           0 :         handle_t *handle = ext4_journal_current_handle();
    1264           0 :         struct inode *inode = mapping->host;
    1265           0 :         loff_t old_size = inode->i_size;
    1266           0 :         int ret = 0, ret2;
    1267           0 :         int i_size_changed = 0;
    1268           0 :         bool verity = ext4_verity_in_progress(inode);
    1269             : 
    1270           0 :         trace_ext4_write_end(inode, pos, len, copied);
    1271             : 
    1272           0 :         if (ext4_has_inline_data(inode) &&
    1273             :             ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))
    1274           0 :                 return ext4_write_inline_data_end(inode, pos, len, copied,
    1275             :                                                   folio);
    1276             : 
    1277           0 :         copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
    1278             :         /*
    1279             :          * it's important to update i_size while still holding folio lock:
    1280             :          * page writeout could otherwise come in and zero beyond i_size.
    1281             :          *
    1282             :          * If FS_IOC_ENABLE_VERITY is running on this inode, then Merkle tree
    1283             :          * blocks are being written past EOF, so skip the i_size update.
    1284             :          */
    1285           0 :         if (!verity)
    1286           0 :                 i_size_changed = ext4_update_inode_size(inode, pos + copied);
    1287           0 :         folio_unlock(folio);
    1288           0 :         folio_put(folio);
    1289             : 
    1290           0 :         if (old_size < pos && !verity)
    1291           0 :                 pagecache_isize_extended(inode, old_size, pos);
    1292             :         /*
    1293             :          * Don't mark the inode dirty under folio lock. First, it unnecessarily
    1294             :          * makes the holding time of folio lock longer. Second, it forces lock
    1295             :          * ordering of folio lock and transaction start for journaling
    1296             :          * filesystems.
    1297             :          */
    1298           0 :         if (i_size_changed)
    1299           0 :                 ret = ext4_mark_inode_dirty(handle, inode);
    1300             : 
    1301           0 :         if (pos + len > inode->i_size && !verity && ext4_can_truncate(inode))
    1302             :                 /* if we have allocated more blocks and copied
    1303             :                  * less. We will have blocks allocated outside
    1304             :                  * inode->i_size. So truncate them
    1305             :                  */
    1306           0 :                 ext4_orphan_add(handle, inode);
    1307             : 
    1308           0 :         ret2 = ext4_journal_stop(handle);
    1309           0 :         if (!ret)
    1310           0 :                 ret = ret2;
    1311             : 
    1312           0 :         if (pos + len > inode->i_size && !verity) {
    1313           0 :                 ext4_truncate_failed_write(inode);
    1314             :                 /*
    1315             :                  * If truncate failed early the inode might still be
    1316             :                  * on the orphan list; we need to make sure the inode
    1317             :                  * is removed from the orphan list in that case.
    1318             :                  */
    1319           0 :                 if (inode->i_nlink)
    1320           0 :                         ext4_orphan_del(NULL, inode);
    1321             :         }
    1322             : 
    1323           0 :         return ret ? ret : copied;
    1324             : }
    1325             : 
    1326             : /*
    1327             :  * This is a private version of folio_zero_new_buffers() which doesn't
    1328             :  * set the buffer to be dirty, since in data=journalled mode we need
    1329             :  * to call ext4_dirty_journalled_data() instead.
    1330             :  */
    1331           0 : static void ext4_journalled_zero_new_buffers(handle_t *handle,
    1332             :                                             struct inode *inode,
    1333             :                                             struct folio *folio,
    1334             :                                             unsigned from, unsigned to)
    1335             : {
    1336           0 :         unsigned int block_start = 0, block_end;
    1337           0 :         struct buffer_head *head, *bh;
    1338             : 
    1339           0 :         bh = head = folio_buffers(folio);
    1340           0 :         do {
    1341           0 :                 block_end = block_start + bh->b_size;
    1342           0 :                 if (buffer_new(bh)) {
    1343           0 :                         if (block_end > from && block_start < to) {
    1344           0 :                                 if (!folio_test_uptodate(folio)) {
    1345           0 :                                         unsigned start, size;
    1346             : 
    1347           0 :                                         start = max(from, block_start);
    1348           0 :                                         size = min(to, block_end) - start;
    1349             : 
    1350           0 :                                         folio_zero_range(folio, start, size);
    1351           0 :                                         write_end_fn(handle, inode, bh);
    1352             :                                 }
    1353           0 :                                 clear_buffer_new(bh);
    1354             :                         }
    1355             :                 }
    1356           0 :                 block_start = block_end;
    1357           0 :                 bh = bh->b_this_page;
    1358           0 :         } while (bh != head);
    1359           0 : }
    1360             : 
    1361           0 : static int ext4_journalled_write_end(struct file *file,
    1362             :                                      struct address_space *mapping,
    1363             :                                      loff_t pos, unsigned len, unsigned copied,
    1364             :                                      struct page *page, void *fsdata)
    1365             : {
    1366           0 :         struct folio *folio = page_folio(page);
    1367           0 :         handle_t *handle = ext4_journal_current_handle();
    1368           0 :         struct inode *inode = mapping->host;
    1369           0 :         loff_t old_size = inode->i_size;
    1370           0 :         int ret = 0, ret2;
    1371           0 :         int partial = 0;
    1372           0 :         unsigned from, to;
    1373           0 :         int size_changed = 0;
    1374           0 :         bool verity = ext4_verity_in_progress(inode);
    1375             : 
    1376           0 :         trace_ext4_journalled_write_end(inode, pos, len, copied);
    1377           0 :         from = pos & (PAGE_SIZE - 1);
    1378           0 :         to = from + len;
    1379             : 
    1380           0 :         BUG_ON(!ext4_handle_valid(handle));
    1381             : 
    1382           0 :         if (ext4_has_inline_data(inode))
    1383           0 :                 return ext4_write_inline_data_end(inode, pos, len, copied,
    1384             :                                                   folio);
    1385             : 
    1386           0 :         if (unlikely(copied < len) && !folio_test_uptodate(folio)) {
    1387           0 :                 copied = 0;
    1388           0 :                 ext4_journalled_zero_new_buffers(handle, inode, folio,
    1389             :                                                  from, to);
    1390             :         } else {
    1391           0 :                 if (unlikely(copied < len))
    1392           0 :                         ext4_journalled_zero_new_buffers(handle, inode, folio,
    1393             :                                                          from + copied, to);
    1394           0 :                 ret = ext4_walk_page_buffers(handle, inode,
    1395             :                                              folio_buffers(folio),
    1396             :                                              from, from + copied, &partial,
    1397             :                                              write_end_fn);
    1398           0 :                 if (!partial)
    1399           0 :                         folio_mark_uptodate(folio);
    1400             :         }
    1401           0 :         if (!verity)
    1402           0 :                 size_changed = ext4_update_inode_size(inode, pos + copied);
    1403           0 :         EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
    1404           0 :         folio_unlock(folio);
    1405           0 :         folio_put(folio);
    1406             : 
    1407           0 :         if (old_size < pos && !verity)
    1408           0 :                 pagecache_isize_extended(inode, old_size, pos);
    1409             : 
    1410           0 :         if (size_changed) {
    1411           0 :                 ret2 = ext4_mark_inode_dirty(handle, inode);
    1412           0 :                 if (!ret)
    1413           0 :                         ret = ret2;
    1414             :         }
    1415             : 
    1416           0 :         if (pos + len > inode->i_size && !verity && ext4_can_truncate(inode))
    1417             :                 /* if we have allocated more blocks and copied
    1418             :                  * less. We will have blocks allocated outside
    1419             :                  * inode->i_size. So truncate them
    1420             :                  */
    1421           0 :                 ext4_orphan_add(handle, inode);
    1422             : 
    1423           0 :         ret2 = ext4_journal_stop(handle);
    1424           0 :         if (!ret)
    1425           0 :                 ret = ret2;
    1426           0 :         if (pos + len > inode->i_size && !verity) {
    1427           0 :                 ext4_truncate_failed_write(inode);
    1428             :                 /*
    1429             :                  * If truncate failed early the inode might still be
    1430             :                  * on the orphan list; we need to make sure the inode
    1431             :                  * is removed from the orphan list in that case.
    1432             :                  */
    1433           0 :                 if (inode->i_nlink)
    1434           0 :                         ext4_orphan_del(NULL, inode);
    1435             :         }
    1436             : 
    1437           0 :         return ret ? ret : copied;
    1438             : }
    1439             : 
    1440             : /*
    1441             :  * Reserve space for a single cluster
    1442             :  */
    1443           0 : static int ext4_da_reserve_space(struct inode *inode)
    1444             : {
    1445           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    1446           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    1447           0 :         int ret;
    1448             : 
    1449             :         /*
    1450             :          * We will charge metadata quota at writeout time; this saves
    1451             :          * us from metadata over-estimation, though we may go over by
    1452             :          * a small amount in the end.  Here we just reserve for data.
    1453             :          */
    1454           0 :         ret = dquot_reserve_block(inode, EXT4_C2B(sbi, 1));
    1455           0 :         if (ret)
    1456             :                 return ret;
    1457             : 
    1458           0 :         spin_lock(&ei->i_block_reservation_lock);
    1459           0 :         if (ext4_claim_free_clusters(sbi, 1, 0)) {
    1460           0 :                 spin_unlock(&ei->i_block_reservation_lock);
    1461           0 :                 dquot_release_reservation_block(inode, EXT4_C2B(sbi, 1));
    1462           0 :                 return -ENOSPC;
    1463             :         }
    1464           0 :         ei->i_reserved_data_blocks++;
    1465           0 :         trace_ext4_da_reserve_space(inode);
    1466           0 :         spin_unlock(&ei->i_block_reservation_lock);
    1467             : 
    1468           0 :         return 0;       /* success */
    1469             : }
    1470             : 
    1471           0 : void ext4_da_release_space(struct inode *inode, int to_free)
    1472             : {
    1473           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    1474           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    1475             : 
    1476           0 :         if (!to_free)
    1477             :                 return;         /* Nothing to release, exit */
    1478             : 
    1479           0 :         spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
    1480             : 
    1481           0 :         trace_ext4_da_release_space(inode, to_free);
    1482           0 :         if (unlikely(to_free > ei->i_reserved_data_blocks)) {
    1483             :                 /*
    1484             :                  * if there aren't enough reserved blocks, then the
    1485             :                  * counter is messed up somewhere.  Since this
    1486             :                  * function is called from invalidate page, it's
    1487             :                  * harmless to return without any action.
    1488             :                  */
    1489           0 :                 ext4_warning(inode->i_sb, "ext4_da_release_space: "
    1490             :                          "ino %lu, to_free %d with only %d reserved "
    1491             :                          "data blocks", inode->i_ino, to_free,
    1492             :                          ei->i_reserved_data_blocks);
    1493           0 :                 WARN_ON(1);
    1494           0 :                 to_free = ei->i_reserved_data_blocks;
    1495             :         }
    1496           0 :         ei->i_reserved_data_blocks -= to_free;
    1497             : 
    1498             :         /* update fs dirty data blocks counter */
    1499           0 :         percpu_counter_sub(&sbi->s_dirtyclusters_counter, to_free);
    1500             : 
    1501           0 :         spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
    1502             : 
    1503           0 :         dquot_release_reservation_block(inode, EXT4_C2B(sbi, to_free));
    1504             : }
    1505             : 
    1506             : /*
    1507             :  * Delayed allocation stuff
    1508             :  */
    1509             : 
    1510             : struct mpage_da_data {
    1511             :         /* These are input fields for ext4_do_writepages() */
    1512             :         struct inode *inode;
    1513             :         struct writeback_control *wbc;
    1514             :         unsigned int can_map:1; /* Can writepages call map blocks? */
    1515             : 
    1516             :         /* These are internal state of ext4_do_writepages() */
    1517             :         pgoff_t first_page;     /* The first page to write */
    1518             :         pgoff_t next_page;      /* Current page to examine */
    1519             :         pgoff_t last_page;      /* Last page to examine */
    1520             :         /*
    1521             :          * Extent to map - this can be after first_page because that can be
    1522             :          * fully mapped. We somewhat abuse m_flags to store whether the extent
    1523             :          * is delalloc or unwritten.
    1524             :          */
    1525             :         struct ext4_map_blocks map;
    1526             :         struct ext4_io_submit io_submit;        /* IO submission data */
    1527             :         unsigned int do_map:1;
    1528             :         unsigned int scanned_until_end:1;
    1529             :         unsigned int journalled_more_data:1;
    1530             : };
    1531             : 
    1532           0 : static void mpage_release_unused_pages(struct mpage_da_data *mpd,
    1533             :                                        bool invalidate)
    1534             : {
    1535           0 :         unsigned nr, i;
    1536           0 :         pgoff_t index, end;
    1537           0 :         struct folio_batch fbatch;
    1538           0 :         struct inode *inode = mpd->inode;
    1539           0 :         struct address_space *mapping = inode->i_mapping;
    1540             : 
    1541             :         /* This is necessary when next_page == 0. */
    1542           0 :         if (mpd->first_page >= mpd->next_page)
    1543           0 :                 return;
    1544             : 
    1545           0 :         mpd->scanned_until_end = 0;
    1546           0 :         index = mpd->first_page;
    1547           0 :         end   = mpd->next_page - 1;
    1548           0 :         if (invalidate) {
    1549           0 :                 ext4_lblk_t start, last;
    1550           0 :                 start = index << (PAGE_SHIFT - inode->i_blkbits);
    1551           0 :                 last = end << (PAGE_SHIFT - inode->i_blkbits);
    1552             : 
    1553             :                 /*
    1554             :                  * avoid racing with extent status tree scans made by
    1555             :                  * ext4_insert_delayed_block()
    1556             :                  */
    1557           0 :                 down_write(&EXT4_I(inode)->i_data_sem);
    1558           0 :                 ext4_es_remove_extent(inode, start, last - start + 1);
    1559           0 :                 up_write(&EXT4_I(inode)->i_data_sem);
    1560             :         }
    1561             : 
    1562           0 :         folio_batch_init(&fbatch);
    1563           0 :         while (index <= end) {
    1564           0 :                 nr = filemap_get_folios(mapping, &index, end, &fbatch);
    1565           0 :                 if (nr == 0)
    1566             :                         break;
    1567           0 :                 for (i = 0; i < nr; i++) {
    1568           0 :                         struct folio *folio = fbatch.folios[i];
    1569             : 
    1570           0 :                         if (folio->index < mpd->first_page)
    1571           0 :                                 continue;
    1572           0 :                         if (folio->index + folio_nr_pages(folio) - 1 > end)
    1573           0 :                                 continue;
    1574           0 :                         BUG_ON(!folio_test_locked(folio));
    1575           0 :                         BUG_ON(folio_test_writeback(folio));
    1576           0 :                         if (invalidate) {
    1577           0 :                                 if (folio_mapped(folio))
    1578           0 :                                         folio_clear_dirty_for_io(folio);
    1579           0 :                                 block_invalidate_folio(folio, 0,
    1580             :                                                 folio_size(folio));
    1581           0 :                                 folio_clear_uptodate(folio);
    1582             :                         }
    1583           0 :                         folio_unlock(folio);
    1584             :                 }
    1585           0 :                 folio_batch_release(&fbatch);
    1586             :         }
    1587             : }
    1588             : 
    1589           0 : static void ext4_print_free_blocks(struct inode *inode)
    1590             : {
    1591           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    1592           0 :         struct super_block *sb = inode->i_sb;
    1593           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    1594             : 
    1595           0 :         ext4_msg(sb, KERN_CRIT, "Total free blocks count %lld",
    1596             :                EXT4_C2B(EXT4_SB(inode->i_sb),
    1597             :                         ext4_count_free_clusters(sb)));
    1598           0 :         ext4_msg(sb, KERN_CRIT, "Free/Dirty block details");
    1599           0 :         ext4_msg(sb, KERN_CRIT, "free_blocks=%lld",
    1600             :                (long long) EXT4_C2B(EXT4_SB(sb),
    1601             :                 percpu_counter_sum(&sbi->s_freeclusters_counter)));
    1602           0 :         ext4_msg(sb, KERN_CRIT, "dirty_blocks=%lld",
    1603             :                (long long) EXT4_C2B(EXT4_SB(sb),
    1604             :                 percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
    1605           0 :         ext4_msg(sb, KERN_CRIT, "Block reservation details");
    1606           0 :         ext4_msg(sb, KERN_CRIT, "i_reserved_data_blocks=%u",
    1607             :                  ei->i_reserved_data_blocks);
    1608           0 :         return;
    1609             : }
    1610             : 
    1611             : /*
    1612             :  * ext4_insert_delayed_block - adds a delayed block to the extents status
    1613             :  *                             tree, incrementing the reserved cluster/block
    1614             :  *                             count or making a pending reservation
    1615             :  *                             where needed
    1616             :  *
    1617             :  * @inode - file containing the newly added block
    1618             :  * @lblk - logical block to be added
    1619             :  *
    1620             :  * Returns 0 on success, negative error code on failure.
    1621             :  */
    1622           0 : static int ext4_insert_delayed_block(struct inode *inode, ext4_lblk_t lblk)
    1623             : {
    1624           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    1625           0 :         int ret;
    1626           0 :         bool allocated = false;
    1627             : 
    1628             :         /*
    1629             :          * If the cluster containing lblk is shared with a delayed,
    1630             :          * written, or unwritten extent in a bigalloc file system, it's
    1631             :          * already been accounted for and does not need to be reserved.
    1632             :          * A pending reservation must be made for the cluster if it's
    1633             :          * shared with a written or unwritten extent and doesn't already
    1634             :          * have one.  Written and unwritten extents can be purged from the
    1635             :          * extents status tree if the system is under memory pressure, so
    1636             :          * it's necessary to examine the extent tree if a search of the
    1637             :          * extents status tree doesn't get a match.
    1638             :          */
    1639           0 :         if (sbi->s_cluster_ratio == 1) {
    1640           0 :                 ret = ext4_da_reserve_space(inode);
    1641           0 :                 if (ret != 0)   /* ENOSPC */
    1642             :                         return ret;
    1643             :         } else {   /* bigalloc */
    1644           0 :                 if (!ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk)) {
    1645           0 :                         if (!ext4_es_scan_clu(inode,
    1646             :                                               &ext4_es_is_mapped, lblk)) {
    1647           0 :                                 ret = ext4_clu_mapped(inode,
    1648           0 :                                                       EXT4_B2C(sbi, lblk));
    1649           0 :                                 if (ret < 0)
    1650             :                                         return ret;
    1651           0 :                                 if (ret == 0) {
    1652           0 :                                         ret = ext4_da_reserve_space(inode);
    1653           0 :                                         if (ret != 0)   /* ENOSPC */
    1654             :                                                 return ret;
    1655             :                                 } else {
    1656             :                                         allocated = true;
    1657             :                                 }
    1658             :                         } else {
    1659             :                                 allocated = true;
    1660             :                         }
    1661             :                 }
    1662             :         }
    1663             : 
    1664           0 :         ext4_es_insert_delayed_block(inode, lblk, allocated);
    1665           0 :         return 0;
    1666             : }
    1667             : 
    1668             : /*
    1669             :  * This function is grabs code from the very beginning of
    1670             :  * ext4_map_blocks, but assumes that the caller is from delayed write
    1671             :  * time. This function looks up the requested blocks and sets the
    1672             :  * buffer delay bit under the protection of i_data_sem.
    1673             :  */
    1674           0 : static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
    1675             :                               struct ext4_map_blocks *map,
    1676             :                               struct buffer_head *bh)
    1677             : {
    1678           0 :         struct extent_status es;
    1679           0 :         int retval;
    1680           0 :         sector_t invalid_block = ~((sector_t) 0xffff);
    1681             : #ifdef ES_AGGRESSIVE_TEST
    1682             :         struct ext4_map_blocks orig_map;
    1683             : 
    1684             :         memcpy(&orig_map, map, sizeof(*map));
    1685             : #endif
    1686             : 
    1687           0 :         if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
    1688           0 :                 invalid_block = ~0;
    1689             : 
    1690           0 :         map->m_flags = 0;
    1691           0 :         ext_debug(inode, "max_blocks %u, logical block %lu\n", map->m_len,
    1692             :                   (unsigned long) map->m_lblk);
    1693             : 
    1694             :         /* Lookup extent status tree firstly */
    1695           0 :         if (ext4_es_lookup_extent(inode, iblock, NULL, &es)) {
    1696           0 :                 if (ext4_es_is_hole(&es)) {
    1697           0 :                         retval = 0;
    1698           0 :                         down_read(&EXT4_I(inode)->i_data_sem);
    1699           0 :                         goto add_delayed;
    1700             :                 }
    1701             : 
    1702             :                 /*
    1703             :                  * Delayed extent could be allocated by fallocate.
    1704             :                  * So we need to check it.
    1705             :                  */
    1706           0 :                 if (ext4_es_is_delayed(&es) && !ext4_es_is_unwritten(&es)) {
    1707           0 :                         map_bh(bh, inode->i_sb, invalid_block);
    1708           0 :                         set_buffer_new(bh);
    1709           0 :                         set_buffer_delay(bh);
    1710           0 :                         return 0;
    1711             :                 }
    1712             : 
    1713           0 :                 map->m_pblk = ext4_es_pblock(&es) + iblock - es.es_lblk;
    1714           0 :                 retval = es.es_len - (iblock - es.es_lblk);
    1715           0 :                 if (retval > map->m_len)
    1716             :                         retval = map->m_len;
    1717           0 :                 map->m_len = retval;
    1718           0 :                 if (ext4_es_is_written(&es))
    1719           0 :                         map->m_flags |= EXT4_MAP_MAPPED;
    1720           0 :                 else if (ext4_es_is_unwritten(&es))
    1721           0 :                         map->m_flags |= EXT4_MAP_UNWRITTEN;
    1722             :                 else
    1723           0 :                         BUG();
    1724             : 
    1725             : #ifdef ES_AGGRESSIVE_TEST
    1726             :                 ext4_map_blocks_es_recheck(NULL, inode, map, &orig_map, 0);
    1727             : #endif
    1728           0 :                 return retval;
    1729             :         }
    1730             : 
    1731             :         /*
    1732             :          * Try to see if we can get the block without requesting a new
    1733             :          * file system block.
    1734             :          */
    1735           0 :         down_read(&EXT4_I(inode)->i_data_sem);
    1736           0 :         if (ext4_has_inline_data(inode))
    1737             :                 retval = 0;
    1738           0 :         else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    1739           0 :                 retval = ext4_ext_map_blocks(NULL, inode, map, 0);
    1740             :         else
    1741           0 :                 retval = ext4_ind_map_blocks(NULL, inode, map, 0);
    1742             : 
    1743           0 : add_delayed:
    1744           0 :         if (retval == 0) {
    1745           0 :                 int ret;
    1746             : 
    1747             :                 /*
    1748             :                  * XXX: __block_prepare_write() unmaps passed block,
    1749             :                  * is it OK?
    1750             :                  */
    1751             : 
    1752           0 :                 ret = ext4_insert_delayed_block(inode, map->m_lblk);
    1753           0 :                 if (ret != 0) {
    1754           0 :                         retval = ret;
    1755           0 :                         goto out_unlock;
    1756             :                 }
    1757             : 
    1758           0 :                 map_bh(bh, inode->i_sb, invalid_block);
    1759           0 :                 set_buffer_new(bh);
    1760           0 :                 set_buffer_delay(bh);
    1761           0 :         } else if (retval > 0) {
    1762           0 :                 unsigned int status;
    1763             : 
    1764           0 :                 if (unlikely(retval != map->m_len)) {
    1765           0 :                         ext4_warning(inode->i_sb,
    1766             :                                      "ES len assertion failed for inode "
    1767             :                                      "%lu: retval %d != map->m_len %d",
    1768             :                                      inode->i_ino, retval, map->m_len);
    1769           0 :                         WARN_ON(1);
    1770             :                 }
    1771             : 
    1772           0 :                 status = map->m_flags & EXT4_MAP_UNWRITTEN ?
    1773           0 :                                 EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
    1774           0 :                 ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
    1775             :                                       map->m_pblk, status);
    1776             :         }
    1777             : 
    1778           0 : out_unlock:
    1779           0 :         up_read((&EXT4_I(inode)->i_data_sem));
    1780             : 
    1781           0 :         return retval;
    1782             : }
    1783             : 
    1784             : /*
    1785             :  * This is a special get_block_t callback which is used by
    1786             :  * ext4_da_write_begin().  It will either return mapped block or
    1787             :  * reserve space for a single block.
    1788             :  *
    1789             :  * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
    1790             :  * We also have b_blocknr = -1 and b_bdev initialized properly
    1791             :  *
    1792             :  * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
    1793             :  * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
    1794             :  * initialized properly.
    1795             :  */
    1796           0 : int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
    1797             :                            struct buffer_head *bh, int create)
    1798             : {
    1799           0 :         struct ext4_map_blocks map;
    1800           0 :         int ret = 0;
    1801             : 
    1802           0 :         BUG_ON(create == 0);
    1803           0 :         BUG_ON(bh->b_size != inode->i_sb->s_blocksize);
    1804             : 
    1805           0 :         map.m_lblk = iblock;
    1806           0 :         map.m_len = 1;
    1807             : 
    1808             :         /*
    1809             :          * first, we need to know whether the block is allocated already
    1810             :          * preallocated blocks are unmapped but should treated
    1811             :          * the same as allocated blocks.
    1812             :          */
    1813           0 :         ret = ext4_da_map_blocks(inode, iblock, &map, bh);
    1814           0 :         if (ret <= 0)
    1815             :                 return ret;
    1816             : 
    1817           0 :         map_bh(bh, inode->i_sb, map.m_pblk);
    1818           0 :         ext4_update_bh_state(bh, map.m_flags);
    1819             : 
    1820           0 :         if (buffer_unwritten(bh)) {
    1821             :                 /* A delayed write to unwritten bh should be marked
    1822             :                  * new and mapped.  Mapped ensures that we don't do
    1823             :                  * get_block multiple times when we write to the same
    1824             :                  * offset and new ensures that we do proper zero out
    1825             :                  * for partial write.
    1826             :                  */
    1827           0 :                 set_buffer_new(bh);
    1828           0 :                 set_buffer_mapped(bh);
    1829             :         }
    1830             :         return 0;
    1831             : }
    1832             : 
    1833           0 : static void mpage_folio_done(struct mpage_da_data *mpd, struct folio *folio)
    1834             : {
    1835           0 :         mpd->first_page += folio_nr_pages(folio);
    1836           0 :         folio_unlock(folio);
    1837           0 : }
    1838             : 
    1839           0 : static int mpage_submit_folio(struct mpage_da_data *mpd, struct folio *folio)
    1840             : {
    1841           0 :         size_t len;
    1842           0 :         loff_t size;
    1843           0 :         int err;
    1844             : 
    1845           0 :         BUG_ON(folio->index != mpd->first_page);
    1846           0 :         folio_clear_dirty_for_io(folio);
    1847             :         /*
    1848             :          * We have to be very careful here!  Nothing protects writeback path
    1849             :          * against i_size changes and the page can be writeably mapped into
    1850             :          * page tables. So an application can be growing i_size and writing
    1851             :          * data through mmap while writeback runs. folio_clear_dirty_for_io()
    1852             :          * write-protects our page in page tables and the page cannot get
    1853             :          * written to again until we release folio lock. So only after
    1854             :          * folio_clear_dirty_for_io() we are safe to sample i_size for
    1855             :          * ext4_bio_write_folio() to zero-out tail of the written page. We rely
    1856             :          * on the barrier provided by folio_test_clear_dirty() in
    1857             :          * folio_clear_dirty_for_io() to make sure i_size is really sampled only
    1858             :          * after page tables are updated.
    1859             :          */
    1860           0 :         size = i_size_read(mpd->inode);
    1861           0 :         len = folio_size(folio);
    1862           0 :         if (folio_pos(folio) + len > size &&
    1863             :             !ext4_verity_in_progress(mpd->inode))
    1864           0 :                 len = size & ~PAGE_MASK;
    1865           0 :         err = ext4_bio_write_folio(&mpd->io_submit, folio, len);
    1866           0 :         if (!err)
    1867           0 :                 mpd->wbc->nr_to_write--;
    1868             : 
    1869           0 :         return err;
    1870             : }
    1871             : 
    1872             : #define BH_FLAGS (BIT(BH_Unwritten) | BIT(BH_Delay))
    1873             : 
    1874             : /*
    1875             :  * mballoc gives us at most this number of blocks...
    1876             :  * XXX: That seems to be only a limitation of ext4_mb_normalize_request().
    1877             :  * The rest of mballoc seems to handle chunks up to full group size.
    1878             :  */
    1879             : #define MAX_WRITEPAGES_EXTENT_LEN 2048
    1880             : 
    1881             : /*
    1882             :  * mpage_add_bh_to_extent - try to add bh to extent of blocks to map
    1883             :  *
    1884             :  * @mpd - extent of blocks
    1885             :  * @lblk - logical number of the block in the file
    1886             :  * @bh - buffer head we want to add to the extent
    1887             :  *
    1888             :  * The function is used to collect contig. blocks in the same state. If the
    1889             :  * buffer doesn't require mapping for writeback and we haven't started the
    1890             :  * extent of buffers to map yet, the function returns 'true' immediately - the
    1891             :  * caller can write the buffer right away. Otherwise the function returns true
    1892             :  * if the block has been added to the extent, false if the block couldn't be
    1893             :  * added.
    1894             :  */
    1895           0 : static bool mpage_add_bh_to_extent(struct mpage_da_data *mpd, ext4_lblk_t lblk,
    1896             :                                    struct buffer_head *bh)
    1897             : {
    1898           0 :         struct ext4_map_blocks *map = &mpd->map;
    1899             : 
    1900             :         /* Buffer that doesn't need mapping for writeback? */
    1901           0 :         if (!buffer_dirty(bh) || !buffer_mapped(bh) ||
    1902           0 :             (!buffer_delay(bh) && !buffer_unwritten(bh))) {
    1903             :                 /* So far no extent to map => we write the buffer right away */
    1904           0 :                 if (map->m_len == 0)
    1905             :                         return true;
    1906           0 :                 return false;
    1907             :         }
    1908             : 
    1909             :         /* First block in the extent? */
    1910           0 :         if (map->m_len == 0) {
    1911             :                 /* We cannot map unless handle is started... */
    1912           0 :                 if (!mpd->do_map)
    1913             :                         return false;
    1914           0 :                 map->m_lblk = lblk;
    1915           0 :                 map->m_len = 1;
    1916           0 :                 map->m_flags = bh->b_state & BH_FLAGS;
    1917           0 :                 return true;
    1918             :         }
    1919             : 
    1920             :         /* Don't go larger than mballoc is willing to allocate */
    1921           0 :         if (map->m_len >= MAX_WRITEPAGES_EXTENT_LEN)
    1922             :                 return false;
    1923             : 
    1924             :         /* Can we merge the block to our big extent? */
    1925           0 :         if (lblk == map->m_lblk + map->m_len &&
    1926           0 :             (bh->b_state & BH_FLAGS) == map->m_flags) {
    1927           0 :                 map->m_len++;
    1928           0 :                 return true;
    1929             :         }
    1930             :         return false;
    1931             : }
    1932             : 
    1933             : /*
    1934             :  * mpage_process_page_bufs - submit page buffers for IO or add them to extent
    1935             :  *
    1936             :  * @mpd - extent of blocks for mapping
    1937             :  * @head - the first buffer in the page
    1938             :  * @bh - buffer we should start processing from
    1939             :  * @lblk - logical number of the block in the file corresponding to @bh
    1940             :  *
    1941             :  * Walk through page buffers from @bh upto @head (exclusive) and either submit
    1942             :  * the page for IO if all buffers in this page were mapped and there's no
    1943             :  * accumulated extent of buffers to map or add buffers in the page to the
    1944             :  * extent of buffers to map. The function returns 1 if the caller can continue
    1945             :  * by processing the next page, 0 if it should stop adding buffers to the
    1946             :  * extent to map because we cannot extend it anymore. It can also return value
    1947             :  * < 0 in case of error during IO submission.
    1948             :  */
    1949           0 : static int mpage_process_page_bufs(struct mpage_da_data *mpd,
    1950             :                                    struct buffer_head *head,
    1951             :                                    struct buffer_head *bh,
    1952             :                                    ext4_lblk_t lblk)
    1953             : {
    1954           0 :         struct inode *inode = mpd->inode;
    1955           0 :         int err;
    1956           0 :         ext4_lblk_t blocks = (i_size_read(inode) + i_blocksize(inode) - 1)
    1957           0 :                                                         >> inode->i_blkbits;
    1958             : 
    1959           0 :         if (ext4_verity_in_progress(inode))
    1960             :                 blocks = EXT_MAX_BLOCKS;
    1961             : 
    1962           0 :         do {
    1963           0 :                 BUG_ON(buffer_locked(bh));
    1964             : 
    1965           0 :                 if (lblk >= blocks || !mpage_add_bh_to_extent(mpd, lblk, bh)) {
    1966             :                         /* Found extent to map? */
    1967           0 :                         if (mpd->map.m_len)
    1968             :                                 return 0;
    1969             :                         /* Buffer needs mapping and handle is not started? */
    1970           0 :                         if (!mpd->do_map)
    1971             :                                 return 0;
    1972             :                         /* Everything mapped so far and we hit EOF */
    1973             :                         break;
    1974             :                 }
    1975           0 :         } while (lblk++, (bh = bh->b_this_page) != head);
    1976             :         /* So far everything mapped? Submit the page for IO. */
    1977           0 :         if (mpd->map.m_len == 0) {
    1978           0 :                 err = mpage_submit_folio(mpd, head->b_folio);
    1979           0 :                 if (err < 0)
    1980             :                         return err;
    1981           0 :                 mpage_folio_done(mpd, head->b_folio);
    1982             :         }
    1983           0 :         if (lblk >= blocks) {
    1984           0 :                 mpd->scanned_until_end = 1;
    1985           0 :                 return 0;
    1986             :         }
    1987             :         return 1;
    1988             : }
    1989             : 
    1990             : /*
    1991             :  * mpage_process_folio - update folio buffers corresponding to changed extent
    1992             :  *                       and may submit fully mapped page for IO
    1993             :  * @mpd: description of extent to map, on return next extent to map
    1994             :  * @folio: Contains these buffers.
    1995             :  * @m_lblk: logical block mapping.
    1996             :  * @m_pblk: corresponding physical mapping.
    1997             :  * @map_bh: determines on return whether this page requires any further
    1998             :  *                mapping or not.
    1999             :  *
    2000             :  * Scan given folio buffers corresponding to changed extent and update buffer
    2001             :  * state according to new extent state.
    2002             :  * We map delalloc buffers to their physical location, clear unwritten bits.
    2003             :  * If the given folio is not fully mapped, we update @mpd to the next extent in
    2004             :  * the given folio that needs mapping & return @map_bh as true.
    2005             :  */
    2006           0 : static int mpage_process_folio(struct mpage_da_data *mpd, struct folio *folio,
    2007             :                               ext4_lblk_t *m_lblk, ext4_fsblk_t *m_pblk,
    2008             :                               bool *map_bh)
    2009             : {
    2010           0 :         struct buffer_head *head, *bh;
    2011           0 :         ext4_io_end_t *io_end = mpd->io_submit.io_end;
    2012           0 :         ext4_lblk_t lblk = *m_lblk;
    2013           0 :         ext4_fsblk_t pblock = *m_pblk;
    2014           0 :         int err = 0;
    2015           0 :         int blkbits = mpd->inode->i_blkbits;
    2016           0 :         ssize_t io_end_size = 0;
    2017           0 :         struct ext4_io_end_vec *io_end_vec = ext4_last_io_end_vec(io_end);
    2018             : 
    2019           0 :         bh = head = folio_buffers(folio);
    2020           0 :         do {
    2021           0 :                 if (lblk < mpd->map.m_lblk)
    2022           0 :                         continue;
    2023           0 :                 if (lblk >= mpd->map.m_lblk + mpd->map.m_len) {
    2024             :                         /*
    2025             :                          * Buffer after end of mapped extent.
    2026             :                          * Find next buffer in the folio to map.
    2027             :                          */
    2028           0 :                         mpd->map.m_len = 0;
    2029           0 :                         mpd->map.m_flags = 0;
    2030           0 :                         io_end_vec->size += io_end_size;
    2031             : 
    2032           0 :                         err = mpage_process_page_bufs(mpd, head, bh, lblk);
    2033           0 :                         if (err > 0)
    2034             :                                 err = 0;
    2035           0 :                         if (!err && mpd->map.m_len && mpd->map.m_lblk > lblk) {
    2036           0 :                                 io_end_vec = ext4_alloc_io_end_vec(io_end);
    2037           0 :                                 if (IS_ERR(io_end_vec)) {
    2038           0 :                                         err = PTR_ERR(io_end_vec);
    2039           0 :                                         goto out;
    2040             :                                 }
    2041           0 :                                 io_end_vec->offset = (loff_t)mpd->map.m_lblk << blkbits;
    2042             :                         }
    2043           0 :                         *map_bh = true;
    2044           0 :                         goto out;
    2045             :                 }
    2046           0 :                 if (buffer_delay(bh)) {
    2047           0 :                         clear_buffer_delay(bh);
    2048           0 :                         bh->b_blocknr = pblock++;
    2049             :                 }
    2050           0 :                 clear_buffer_unwritten(bh);
    2051           0 :                 io_end_size += (1 << blkbits);
    2052           0 :         } while (lblk++, (bh = bh->b_this_page) != head);
    2053             : 
    2054           0 :         io_end_vec->size += io_end_size;
    2055           0 :         *map_bh = false;
    2056           0 : out:
    2057           0 :         *m_lblk = lblk;
    2058           0 :         *m_pblk = pblock;
    2059           0 :         return err;
    2060             : }
    2061             : 
    2062             : /*
    2063             :  * mpage_map_buffers - update buffers corresponding to changed extent and
    2064             :  *                     submit fully mapped pages for IO
    2065             :  *
    2066             :  * @mpd - description of extent to map, on return next extent to map
    2067             :  *
    2068             :  * Scan buffers corresponding to changed extent (we expect corresponding pages
    2069             :  * to be already locked) and update buffer state according to new extent state.
    2070             :  * We map delalloc buffers to their physical location, clear unwritten bits,
    2071             :  * and mark buffers as uninit when we perform writes to unwritten extents
    2072             :  * and do extent conversion after IO is finished. If the last page is not fully
    2073             :  * mapped, we update @map to the next extent in the last page that needs
    2074             :  * mapping. Otherwise we submit the page for IO.
    2075             :  */
    2076           0 : static int mpage_map_and_submit_buffers(struct mpage_da_data *mpd)
    2077             : {
    2078           0 :         struct folio_batch fbatch;
    2079           0 :         unsigned nr, i;
    2080           0 :         struct inode *inode = mpd->inode;
    2081           0 :         int bpp_bits = PAGE_SHIFT - inode->i_blkbits;
    2082           0 :         pgoff_t start, end;
    2083           0 :         ext4_lblk_t lblk;
    2084           0 :         ext4_fsblk_t pblock;
    2085           0 :         int err;
    2086           0 :         bool map_bh = false;
    2087             : 
    2088           0 :         start = mpd->map.m_lblk >> bpp_bits;
    2089           0 :         end = (mpd->map.m_lblk + mpd->map.m_len - 1) >> bpp_bits;
    2090           0 :         lblk = start << bpp_bits;
    2091           0 :         pblock = mpd->map.m_pblk;
    2092             : 
    2093           0 :         folio_batch_init(&fbatch);
    2094           0 :         while (start <= end) {
    2095           0 :                 nr = filemap_get_folios(inode->i_mapping, &start, end, &fbatch);
    2096           0 :                 if (nr == 0)
    2097             :                         break;
    2098           0 :                 for (i = 0; i < nr; i++) {
    2099           0 :                         struct folio *folio = fbatch.folios[i];
    2100             : 
    2101           0 :                         err = mpage_process_folio(mpd, folio, &lblk, &pblock,
    2102             :                                                  &map_bh);
    2103             :                         /*
    2104             :                          * If map_bh is true, means page may require further bh
    2105             :                          * mapping, or maybe the page was submitted for IO.
    2106             :                          * So we return to call further extent mapping.
    2107             :                          */
    2108           0 :                         if (err < 0 || map_bh)
    2109           0 :                                 goto out;
    2110             :                         /* Page fully mapped - let IO run! */
    2111           0 :                         err = mpage_submit_folio(mpd, folio);
    2112           0 :                         if (err < 0)
    2113           0 :                                 goto out;
    2114           0 :                         mpage_folio_done(mpd, folio);
    2115             :                 }
    2116           0 :                 folio_batch_release(&fbatch);
    2117             :         }
    2118             :         /* Extent fully mapped and matches with page boundary. We are done. */
    2119           0 :         mpd->map.m_len = 0;
    2120           0 :         mpd->map.m_flags = 0;
    2121           0 :         return 0;
    2122           0 : out:
    2123           0 :         folio_batch_release(&fbatch);
    2124             :         return err;
    2125             : }
    2126             : 
    2127           0 : static int mpage_map_one_extent(handle_t *handle, struct mpage_da_data *mpd)
    2128             : {
    2129           0 :         struct inode *inode = mpd->inode;
    2130           0 :         struct ext4_map_blocks *map = &mpd->map;
    2131           0 :         int get_blocks_flags;
    2132           0 :         int err, dioread_nolock;
    2133             : 
    2134           0 :         trace_ext4_da_write_pages_extent(inode, map);
    2135             :         /*
    2136             :          * Call ext4_map_blocks() to allocate any delayed allocation blocks, or
    2137             :          * to convert an unwritten extent to be initialized (in the case
    2138             :          * where we have written into one or more preallocated blocks).  It is
    2139             :          * possible that we're going to need more metadata blocks than
    2140             :          * previously reserved. However we must not fail because we're in
    2141             :          * writeback and there is nothing we can do about it so it might result
    2142             :          * in data loss.  So use reserved blocks to allocate metadata if
    2143             :          * possible.
    2144             :          *
    2145             :          * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE if
    2146             :          * the blocks in question are delalloc blocks.  This indicates
    2147             :          * that the blocks and quotas has already been checked when
    2148             :          * the data was copied into the page cache.
    2149             :          */
    2150           0 :         get_blocks_flags = EXT4_GET_BLOCKS_CREATE |
    2151             :                            EXT4_GET_BLOCKS_METADATA_NOFAIL |
    2152             :                            EXT4_GET_BLOCKS_IO_SUBMIT;
    2153           0 :         dioread_nolock = ext4_should_dioread_nolock(inode);
    2154           0 :         if (dioread_nolock)
    2155           0 :                 get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT;
    2156           0 :         if (map->m_flags & BIT(BH_Delay))
    2157           0 :                 get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE;
    2158             : 
    2159           0 :         err = ext4_map_blocks(handle, inode, map, get_blocks_flags);
    2160           0 :         if (err < 0)
    2161             :                 return err;
    2162           0 :         if (dioread_nolock && (map->m_flags & EXT4_MAP_UNWRITTEN)) {
    2163           0 :                 if (!mpd->io_submit.io_end->handle &&
    2164             :                     ext4_handle_valid(handle)) {
    2165           0 :                         mpd->io_submit.io_end->handle = handle->h_rsv_handle;
    2166           0 :                         handle->h_rsv_handle = NULL;
    2167             :                 }
    2168           0 :                 ext4_set_io_unwritten_flag(inode, mpd->io_submit.io_end);
    2169             :         }
    2170             : 
    2171           0 :         BUG_ON(map->m_len == 0);
    2172             :         return 0;
    2173             : }
    2174             : 
    2175             : /*
    2176             :  * mpage_map_and_submit_extent - map extent starting at mpd->lblk of length
    2177             :  *                               mpd->len and submit pages underlying it for IO
    2178             :  *
    2179             :  * @handle - handle for journal operations
    2180             :  * @mpd - extent to map
    2181             :  * @give_up_on_write - we set this to true iff there is a fatal error and there
    2182             :  *                     is no hope of writing the data. The caller should discard
    2183             :  *                     dirty pages to avoid infinite loops.
    2184             :  *
    2185             :  * The function maps extent starting at mpd->lblk of length mpd->len. If it is
    2186             :  * delayed, blocks are allocated, if it is unwritten, we may need to convert
    2187             :  * them to initialized or split the described range from larger unwritten
    2188             :  * extent. Note that we need not map all the described range since allocation
    2189             :  * can return less blocks or the range is covered by more unwritten extents. We
    2190             :  * cannot map more because we are limited by reserved transaction credits. On
    2191             :  * the other hand we always make sure that the last touched page is fully
    2192             :  * mapped so that it can be written out (and thus forward progress is
    2193             :  * guaranteed). After mapping we submit all mapped pages for IO.
    2194             :  */
    2195           0 : static int mpage_map_and_submit_extent(handle_t *handle,
    2196             :                                        struct mpage_da_data *mpd,
    2197             :                                        bool *give_up_on_write)
    2198             : {
    2199           0 :         struct inode *inode = mpd->inode;
    2200           0 :         struct ext4_map_blocks *map = &mpd->map;
    2201           0 :         int err;
    2202           0 :         loff_t disksize;
    2203           0 :         int progress = 0;
    2204           0 :         ext4_io_end_t *io_end = mpd->io_submit.io_end;
    2205           0 :         struct ext4_io_end_vec *io_end_vec;
    2206             : 
    2207           0 :         io_end_vec = ext4_alloc_io_end_vec(io_end);
    2208           0 :         if (IS_ERR(io_end_vec))
    2209           0 :                 return PTR_ERR(io_end_vec);
    2210           0 :         io_end_vec->offset = ((loff_t)map->m_lblk) << inode->i_blkbits;
    2211           0 :         do {
    2212           0 :                 err = mpage_map_one_extent(handle, mpd);
    2213           0 :                 if (err < 0) {
    2214           0 :                         struct super_block *sb = inode->i_sb;
    2215             : 
    2216           0 :                         if (ext4_forced_shutdown(EXT4_SB(sb)) ||
    2217             :                             ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
    2218           0 :                                 goto invalidate_dirty_pages;
    2219             :                         /*
    2220             :                          * Let the uper layers retry transient errors.
    2221             :                          * In the case of ENOSPC, if ext4_count_free_blocks()
    2222             :                          * is non-zero, a commit should free up blocks.
    2223             :                          */
    2224           0 :                         if ((err == -ENOMEM) ||
    2225           0 :                             (err == -ENOSPC && ext4_count_free_clusters(sb))) {
    2226           0 :                                 if (progress)
    2227           0 :                                         goto update_disksize;
    2228             :                                 return err;
    2229             :                         }
    2230           0 :                         ext4_msg(sb, KERN_CRIT,
    2231             :                                  "Delayed block allocation failed for "
    2232             :                                  "inode %lu at logical offset %llu with"
    2233             :                                  " max blocks %u with error %d",
    2234             :                                  inode->i_ino,
    2235             :                                  (unsigned long long)map->m_lblk,
    2236             :                                  (unsigned)map->m_len, -err);
    2237           0 :                         ext4_msg(sb, KERN_CRIT,
    2238             :                                  "This should not happen!! Data will "
    2239             :                                  "be lost\n");
    2240           0 :                         if (err == -ENOSPC)
    2241           0 :                                 ext4_print_free_blocks(inode);
    2242           0 :                 invalidate_dirty_pages:
    2243           0 :                         *give_up_on_write = true;
    2244           0 :                         return err;
    2245             :                 }
    2246           0 :                 progress = 1;
    2247             :                 /*
    2248             :                  * Update buffer state, submit mapped pages, and get us new
    2249             :                  * extent to map
    2250             :                  */
    2251           0 :                 err = mpage_map_and_submit_buffers(mpd);
    2252           0 :                 if (err < 0)
    2253           0 :                         goto update_disksize;
    2254           0 :         } while (map->m_len);
    2255             : 
    2256           0 : update_disksize:
    2257             :         /*
    2258             :          * Update on-disk size after IO is submitted.  Races with
    2259             :          * truncate are avoided by checking i_size under i_data_sem.
    2260             :          */
    2261           0 :         disksize = ((loff_t)mpd->first_page) << PAGE_SHIFT;
    2262           0 :         if (disksize > READ_ONCE(EXT4_I(inode)->i_disksize)) {
    2263           0 :                 int err2;
    2264           0 :                 loff_t i_size;
    2265             : 
    2266           0 :                 down_write(&EXT4_I(inode)->i_data_sem);
    2267           0 :                 i_size = i_size_read(inode);
    2268           0 :                 if (disksize > i_size)
    2269             :                         disksize = i_size;
    2270           0 :                 if (disksize > EXT4_I(inode)->i_disksize)
    2271           0 :                         EXT4_I(inode)->i_disksize = disksize;
    2272           0 :                 up_write(&EXT4_I(inode)->i_data_sem);
    2273           0 :                 err2 = ext4_mark_inode_dirty(handle, inode);
    2274           0 :                 if (err2) {
    2275           0 :                         ext4_error_err(inode->i_sb, -err2,
    2276             :                                        "Failed to mark inode %lu dirty",
    2277             :                                        inode->i_ino);
    2278             :                 }
    2279           0 :                 if (!err)
    2280           0 :                         err = err2;
    2281             :         }
    2282             :         return err;
    2283             : }
    2284             : 
    2285             : /*
    2286             :  * Calculate the total number of credits to reserve for one writepages
    2287             :  * iteration. This is called from ext4_writepages(). We map an extent of
    2288             :  * up to MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping
    2289             :  * the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN +
    2290             :  * bpp - 1 blocks in bpp different extents.
    2291             :  */
    2292           0 : static int ext4_da_writepages_trans_blocks(struct inode *inode)
    2293             : {
    2294           0 :         int bpp = ext4_journal_blocks_per_page(inode);
    2295             : 
    2296           0 :         return ext4_meta_trans_blocks(inode,
    2297             :                                 MAX_WRITEPAGES_EXTENT_LEN + bpp - 1, bpp);
    2298             : }
    2299             : 
    2300           0 : static int ext4_journal_folio_buffers(handle_t *handle, struct folio *folio,
    2301             :                                      size_t len)
    2302             : {
    2303           0 :         struct buffer_head *page_bufs = folio_buffers(folio);
    2304           0 :         struct inode *inode = folio->mapping->host;
    2305           0 :         int ret, err;
    2306             : 
    2307           0 :         ret = ext4_walk_page_buffers(handle, inode, page_bufs, 0, len,
    2308             :                                      NULL, do_journal_get_write_access);
    2309           0 :         err = ext4_walk_page_buffers(handle, inode, page_bufs, 0, len,
    2310             :                                      NULL, write_end_fn);
    2311           0 :         if (ret == 0)
    2312           0 :                 ret = err;
    2313           0 :         err = ext4_jbd2_inode_add_write(handle, inode, folio_pos(folio), len);
    2314           0 :         if (ret == 0)
    2315           0 :                 ret = err;
    2316           0 :         EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
    2317             : 
    2318           0 :         return ret;
    2319             : }
    2320             : 
    2321           0 : static int mpage_journal_page_buffers(handle_t *handle,
    2322             :                                       struct mpage_da_data *mpd,
    2323             :                                       struct folio *folio)
    2324             : {
    2325           0 :         struct inode *inode = mpd->inode;
    2326           0 :         loff_t size = i_size_read(inode);
    2327           0 :         size_t len = folio_size(folio);
    2328             : 
    2329           0 :         folio_clear_checked(folio);
    2330           0 :         mpd->wbc->nr_to_write--;
    2331             : 
    2332           0 :         if (folio_pos(folio) + len > size &&
    2333             :             !ext4_verity_in_progress(inode))
    2334           0 :                 len = size - folio_pos(folio);
    2335             : 
    2336           0 :         return ext4_journal_folio_buffers(handle, folio, len);
    2337             : }
    2338             : 
    2339             : /*
    2340             :  * mpage_prepare_extent_to_map - find & lock contiguous range of dirty pages
    2341             :  *                               needing mapping, submit mapped pages
    2342             :  *
    2343             :  * @mpd - where to look for pages
    2344             :  *
    2345             :  * Walk dirty pages in the mapping. If they are fully mapped, submit them for
    2346             :  * IO immediately. If we cannot map blocks, we submit just already mapped
    2347             :  * buffers in the page for IO and keep page dirty. When we can map blocks and
    2348             :  * we find a page which isn't mapped we start accumulating extent of buffers
    2349             :  * underlying these pages that needs mapping (formed by either delayed or
    2350             :  * unwritten buffers). We also lock the pages containing these buffers. The
    2351             :  * extent found is returned in @mpd structure (starting at mpd->lblk with
    2352             :  * length mpd->len blocks).
    2353             :  *
    2354             :  * Note that this function can attach bios to one io_end structure which are
    2355             :  * neither logically nor physically contiguous. Although it may seem as an
    2356             :  * unnecessary complication, it is actually inevitable in blocksize < pagesize
    2357             :  * case as we need to track IO to all buffers underlying a page in one io_end.
    2358             :  */
    2359           0 : static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd)
    2360             : {
    2361           0 :         struct address_space *mapping = mpd->inode->i_mapping;
    2362           0 :         struct folio_batch fbatch;
    2363           0 :         unsigned int nr_folios;
    2364           0 :         pgoff_t index = mpd->first_page;
    2365           0 :         pgoff_t end = mpd->last_page;
    2366           0 :         xa_mark_t tag;
    2367           0 :         int i, err = 0;
    2368           0 :         int blkbits = mpd->inode->i_blkbits;
    2369           0 :         ext4_lblk_t lblk;
    2370           0 :         struct buffer_head *head;
    2371           0 :         handle_t *handle = NULL;
    2372           0 :         int bpp = ext4_journal_blocks_per_page(mpd->inode);
    2373             : 
    2374           0 :         if (mpd->wbc->sync_mode == WB_SYNC_ALL || mpd->wbc->tagged_writepages)
    2375             :                 tag = PAGECACHE_TAG_TOWRITE;
    2376             :         else
    2377           0 :                 tag = PAGECACHE_TAG_DIRTY;
    2378             : 
    2379           0 :         mpd->map.m_len = 0;
    2380           0 :         mpd->next_page = index;
    2381           0 :         if (ext4_should_journal_data(mpd->inode)) {
    2382           0 :                 handle = ext4_journal_start(mpd->inode, EXT4_HT_WRITE_PAGE,
    2383             :                                             bpp);
    2384           0 :                 if (IS_ERR(handle))
    2385           0 :                         return PTR_ERR(handle);
    2386             :         }
    2387           0 :         folio_batch_init(&fbatch);
    2388           0 :         while (index <= end) {
    2389           0 :                 nr_folios = filemap_get_folios_tag(mapping, &index, end,
    2390             :                                 tag, &fbatch);
    2391           0 :                 if (nr_folios == 0)
    2392             :                         break;
    2393             : 
    2394           0 :                 for (i = 0; i < nr_folios; i++) {
    2395           0 :                         struct folio *folio = fbatch.folios[i];
    2396             : 
    2397             :                         /*
    2398             :                          * Accumulated enough dirty pages? This doesn't apply
    2399             :                          * to WB_SYNC_ALL mode. For integrity sync we have to
    2400             :                          * keep going because someone may be concurrently
    2401             :                          * dirtying pages, and we might have synced a lot of
    2402             :                          * newly appeared dirty pages, but have not synced all
    2403             :                          * of the old dirty pages.
    2404             :                          */
    2405           0 :                         if (mpd->wbc->sync_mode == WB_SYNC_NONE &&
    2406           0 :                             mpd->wbc->nr_to_write <=
    2407           0 :                             mpd->map.m_len >> (PAGE_SHIFT - blkbits))
    2408           0 :                                 goto out;
    2409             : 
    2410             :                         /* If we can't merge this page, we are done. */
    2411           0 :                         if (mpd->map.m_len > 0 && mpd->next_page != folio->index)
    2412           0 :                                 goto out;
    2413             : 
    2414           0 :                         if (handle) {
    2415           0 :                                 err = ext4_journal_ensure_credits(handle, bpp,
    2416             :                                                                   0);
    2417           0 :                                 if (err < 0)
    2418           0 :                                         goto out;
    2419             :                         }
    2420             : 
    2421           0 :                         folio_lock(folio);
    2422             :                         /*
    2423             :                          * If the page is no longer dirty, or its mapping no
    2424             :                          * longer corresponds to inode we are writing (which
    2425             :                          * means it has been truncated or invalidated), or the
    2426             :                          * page is already under writeback and we are not doing
    2427             :                          * a data integrity writeback, skip the page
    2428             :                          */
    2429           0 :                         if (!folio_test_dirty(folio) ||
    2430           0 :                             (folio_test_writeback(folio) &&
    2431           0 :                              (mpd->wbc->sync_mode == WB_SYNC_NONE)) ||
    2432           0 :                             unlikely(folio->mapping != mapping)) {
    2433           0 :                                 folio_unlock(folio);
    2434           0 :                                 continue;
    2435             :                         }
    2436             : 
    2437           0 :                         folio_wait_writeback(folio);
    2438           0 :                         BUG_ON(folio_test_writeback(folio));
    2439             : 
    2440             :                         /*
    2441             :                          * Should never happen but for buggy code in
    2442             :                          * other subsystems that call
    2443             :                          * set_page_dirty() without properly warning
    2444             :                          * the file system first.  See [1] for more
    2445             :                          * information.
    2446             :                          *
    2447             :                          * [1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz
    2448             :                          */
    2449           0 :                         if (!folio_buffers(folio)) {
    2450           0 :                                 ext4_warning_inode(mpd->inode, "page %lu does not have buffers attached", folio->index);
    2451           0 :                                 folio_clear_dirty(folio);
    2452           0 :                                 folio_unlock(folio);
    2453           0 :                                 continue;
    2454             :                         }
    2455             : 
    2456           0 :                         if (mpd->map.m_len == 0)
    2457           0 :                                 mpd->first_page = folio->index;
    2458           0 :                         mpd->next_page = folio->index + folio_nr_pages(folio);
    2459             :                         /*
    2460             :                          * Writeout when we cannot modify metadata is simple.
    2461             :                          * Just submit the page. For data=journal mode we
    2462             :                          * first handle writeout of the page for checkpoint and
    2463             :                          * only after that handle delayed page dirtying. This
    2464             :                          * makes sure current data is checkpointed to the final
    2465             :                          * location before possibly journalling it again which
    2466             :                          * is desirable when the page is frequently dirtied
    2467             :                          * through a pin.
    2468             :                          */
    2469           0 :                         if (!mpd->can_map) {
    2470           0 :                                 err = mpage_submit_folio(mpd, folio);
    2471           0 :                                 if (err < 0)
    2472           0 :                                         goto out;
    2473             :                                 /* Pending dirtying of journalled data? */
    2474           0 :                                 if (folio_test_checked(folio)) {
    2475           0 :                                         err = mpage_journal_page_buffers(handle,
    2476             :                                                 mpd, folio);
    2477           0 :                                         if (err < 0)
    2478           0 :                                                 goto out;
    2479           0 :                                         mpd->journalled_more_data = 1;
    2480             :                                 }
    2481           0 :                                 mpage_folio_done(mpd, folio);
    2482             :                         } else {
    2483             :                                 /* Add all dirty buffers to mpd */
    2484           0 :                                 lblk = ((ext4_lblk_t)folio->index) <<
    2485           0 :                                         (PAGE_SHIFT - blkbits);
    2486           0 :                                 head = folio_buffers(folio);
    2487           0 :                                 err = mpage_process_page_bufs(mpd, head, head,
    2488             :                                                 lblk);
    2489           0 :                                 if (err <= 0)
    2490           0 :                                         goto out;
    2491             :                                 err = 0;
    2492             :                         }
    2493             :                 }
    2494           0 :                 folio_batch_release(&fbatch);
    2495           0 :                 cond_resched();
    2496             :         }
    2497           0 :         mpd->scanned_until_end = 1;
    2498           0 :         if (handle)
    2499           0 :                 ext4_journal_stop(handle);
    2500             :         return 0;
    2501           0 : out:
    2502           0 :         folio_batch_release(&fbatch);
    2503           0 :         if (handle)
    2504           0 :                 ext4_journal_stop(handle);
    2505             :         return err;
    2506             : }
    2507             : 
    2508           0 : static int ext4_do_writepages(struct mpage_da_data *mpd)
    2509             : {
    2510           0 :         struct writeback_control *wbc = mpd->wbc;
    2511           0 :         pgoff_t writeback_index = 0;
    2512           0 :         long nr_to_write = wbc->nr_to_write;
    2513           0 :         int range_whole = 0;
    2514           0 :         int cycled = 1;
    2515           0 :         handle_t *handle = NULL;
    2516           0 :         struct inode *inode = mpd->inode;
    2517           0 :         struct address_space *mapping = inode->i_mapping;
    2518           0 :         int needed_blocks, rsv_blocks = 0, ret = 0;
    2519           0 :         struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
    2520           0 :         struct blk_plug plug;
    2521           0 :         bool give_up_on_write = false;
    2522             : 
    2523           0 :         trace_ext4_writepages(inode, wbc);
    2524             : 
    2525             :         /*
    2526             :          * No pages to write? This is mainly a kludge to avoid starting
    2527             :          * a transaction for special inodes like journal inode on last iput()
    2528             :          * because that could violate lock ordering on umount
    2529             :          */
    2530           0 :         if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
    2531           0 :                 goto out_writepages;
    2532             : 
    2533             :         /*
    2534             :          * If the filesystem has aborted, it is read-only, so return
    2535             :          * right away instead of dumping stack traces later on that
    2536             :          * will obscure the real source of the problem.  We test
    2537             :          * EXT4_MF_FS_ABORTED instead of sb->s_flag's SB_RDONLY because
    2538             :          * the latter could be true if the filesystem is mounted
    2539             :          * read-only, and in that case, ext4_writepages should
    2540             :          * *never* be called, so if that ever happens, we would want
    2541             :          * the stack trace.
    2542             :          */
    2543           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(mapping->host->i_sb)) ||
    2544             :                      ext4_test_mount_flag(inode->i_sb, EXT4_MF_FS_ABORTED))) {
    2545           0 :                 ret = -EROFS;
    2546           0 :                 goto out_writepages;
    2547             :         }
    2548             : 
    2549             :         /*
    2550             :          * If we have inline data and arrive here, it means that
    2551             :          * we will soon create the block for the 1st page, so
    2552             :          * we'd better clear the inline data here.
    2553             :          */
    2554           0 :         if (ext4_has_inline_data(inode)) {
    2555             :                 /* Just inode will be modified... */
    2556           0 :                 handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
    2557           0 :                 if (IS_ERR(handle)) {
    2558           0 :                         ret = PTR_ERR(handle);
    2559           0 :                         goto out_writepages;
    2560             :                 }
    2561           0 :                 BUG_ON(ext4_test_inode_state(inode,
    2562             :                                 EXT4_STATE_MAY_INLINE_DATA));
    2563           0 :                 ext4_destroy_inline_data(handle, inode);
    2564           0 :                 ext4_journal_stop(handle);
    2565             :         }
    2566             : 
    2567             :         /*
    2568             :          * data=journal mode does not do delalloc so we just need to writeout /
    2569             :          * journal already mapped buffers. On the other hand we need to commit
    2570             :          * transaction to make data stable. We expect all the data to be
    2571             :          * already in the journal (the only exception are DMA pinned pages
    2572             :          * dirtied behind our back) so we commit transaction here and run the
    2573             :          * writeback loop to checkpoint them. The checkpointing is not actually
    2574             :          * necessary to make data persistent *but* quite a few places (extent
    2575             :          * shifting operations, fsverity, ...) depend on being able to drop
    2576             :          * pagecache pages after calling filemap_write_and_wait() and for that
    2577             :          * checkpointing needs to happen.
    2578             :          */
    2579           0 :         if (ext4_should_journal_data(inode)) {
    2580           0 :                 mpd->can_map = 0;
    2581           0 :                 if (wbc->sync_mode == WB_SYNC_ALL)
    2582           0 :                         ext4_fc_commit(sbi->s_journal,
    2583           0 :                                        EXT4_I(inode)->i_datasync_tid);
    2584             :         }
    2585           0 :         mpd->journalled_more_data = 0;
    2586             : 
    2587           0 :         if (ext4_should_dioread_nolock(inode)) {
    2588             :                 /*
    2589             :                  * We may need to convert up to one extent per block in
    2590             :                  * the page and we may dirty the inode.
    2591             :                  */
    2592           0 :                 rsv_blocks = 1 + ext4_chunk_trans_blocks(inode,
    2593           0 :                                                 PAGE_SIZE >> inode->i_blkbits);
    2594             :         }
    2595             : 
    2596           0 :         if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
    2597           0 :                 range_whole = 1;
    2598             : 
    2599           0 :         if (wbc->range_cyclic) {
    2600           0 :                 writeback_index = mapping->writeback_index;
    2601           0 :                 if (writeback_index)
    2602           0 :                         cycled = 0;
    2603           0 :                 mpd->first_page = writeback_index;
    2604           0 :                 mpd->last_page = -1;
    2605             :         } else {
    2606           0 :                 mpd->first_page = wbc->range_start >> PAGE_SHIFT;
    2607           0 :                 mpd->last_page = wbc->range_end >> PAGE_SHIFT;
    2608             :         }
    2609             : 
    2610           0 :         ext4_io_submit_init(&mpd->io_submit, wbc);
    2611           0 : retry:
    2612           0 :         if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
    2613           0 :                 tag_pages_for_writeback(mapping, mpd->first_page,
    2614             :                                         mpd->last_page);
    2615           0 :         blk_start_plug(&plug);
    2616             : 
    2617             :         /*
    2618             :          * First writeback pages that don't need mapping - we can avoid
    2619             :          * starting a transaction unnecessarily and also avoid being blocked
    2620             :          * in the block layer on device congestion while having transaction
    2621             :          * started.
    2622             :          */
    2623           0 :         mpd->do_map = 0;
    2624           0 :         mpd->scanned_until_end = 0;
    2625           0 :         mpd->io_submit.io_end = ext4_init_io_end(inode, GFP_KERNEL);
    2626           0 :         if (!mpd->io_submit.io_end) {
    2627           0 :                 ret = -ENOMEM;
    2628           0 :                 goto unplug;
    2629             :         }
    2630           0 :         ret = mpage_prepare_extent_to_map(mpd);
    2631             :         /* Unlock pages we didn't use */
    2632           0 :         mpage_release_unused_pages(mpd, false);
    2633             :         /* Submit prepared bio */
    2634           0 :         ext4_io_submit(&mpd->io_submit);
    2635           0 :         ext4_put_io_end_defer(mpd->io_submit.io_end);
    2636           0 :         mpd->io_submit.io_end = NULL;
    2637           0 :         if (ret < 0)
    2638           0 :                 goto unplug;
    2639             : 
    2640           0 :         while (!mpd->scanned_until_end && wbc->nr_to_write > 0) {
    2641             :                 /* For each extent of pages we use new io_end */
    2642           0 :                 mpd->io_submit.io_end = ext4_init_io_end(inode, GFP_KERNEL);
    2643           0 :                 if (!mpd->io_submit.io_end) {
    2644             :                         ret = -ENOMEM;
    2645             :                         break;
    2646             :                 }
    2647             : 
    2648           0 :                 WARN_ON_ONCE(!mpd->can_map);
    2649             :                 /*
    2650             :                  * We have two constraints: We find one extent to map and we
    2651             :                  * must always write out whole page (makes a difference when
    2652             :                  * blocksize < pagesize) so that we don't block on IO when we
    2653             :                  * try to write out the rest of the page. Journalled mode is
    2654             :                  * not supported by delalloc.
    2655             :                  */
    2656           0 :                 BUG_ON(ext4_should_journal_data(inode));
    2657           0 :                 needed_blocks = ext4_da_writepages_trans_blocks(inode);
    2658             : 
    2659             :                 /* start a new transaction */
    2660           0 :                 handle = ext4_journal_start_with_reserve(inode,
    2661             :                                 EXT4_HT_WRITE_PAGE, needed_blocks, rsv_blocks);
    2662           0 :                 if (IS_ERR(handle)) {
    2663           0 :                         ret = PTR_ERR(handle);
    2664           0 :                         ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
    2665             :                                "%ld pages, ino %lu; err %d", __func__,
    2666             :                                 wbc->nr_to_write, inode->i_ino, ret);
    2667             :                         /* Release allocated io_end */
    2668           0 :                         ext4_put_io_end(mpd->io_submit.io_end);
    2669           0 :                         mpd->io_submit.io_end = NULL;
    2670           0 :                         break;
    2671             :                 }
    2672           0 :                 mpd->do_map = 1;
    2673             : 
    2674           0 :                 trace_ext4_da_write_pages(inode, mpd->first_page, wbc);
    2675           0 :                 ret = mpage_prepare_extent_to_map(mpd);
    2676           0 :                 if (!ret && mpd->map.m_len)
    2677           0 :                         ret = mpage_map_and_submit_extent(handle, mpd,
    2678             :                                         &give_up_on_write);
    2679             :                 /*
    2680             :                  * Caution: If the handle is synchronous,
    2681             :                  * ext4_journal_stop() can wait for transaction commit
    2682             :                  * to finish which may depend on writeback of pages to
    2683             :                  * complete or on page lock to be released.  In that
    2684             :                  * case, we have to wait until after we have
    2685             :                  * submitted all the IO, released page locks we hold,
    2686             :                  * and dropped io_end reference (for extent conversion
    2687             :                  * to be able to complete) before stopping the handle.
    2688             :                  */
    2689           0 :                 if (!ext4_handle_valid(handle) || handle->h_sync == 0) {
    2690           0 :                         ext4_journal_stop(handle);
    2691           0 :                         handle = NULL;
    2692           0 :                         mpd->do_map = 0;
    2693             :                 }
    2694             :                 /* Unlock pages we didn't use */
    2695           0 :                 mpage_release_unused_pages(mpd, give_up_on_write);
    2696             :                 /* Submit prepared bio */
    2697           0 :                 ext4_io_submit(&mpd->io_submit);
    2698             : 
    2699             :                 /*
    2700             :                  * Drop our io_end reference we got from init. We have
    2701             :                  * to be careful and use deferred io_end finishing if
    2702             :                  * we are still holding the transaction as we can
    2703             :                  * release the last reference to io_end which may end
    2704             :                  * up doing unwritten extent conversion.
    2705             :                  */
    2706           0 :                 if (handle) {
    2707           0 :                         ext4_put_io_end_defer(mpd->io_submit.io_end);
    2708           0 :                         ext4_journal_stop(handle);
    2709             :                 } else
    2710           0 :                         ext4_put_io_end(mpd->io_submit.io_end);
    2711           0 :                 mpd->io_submit.io_end = NULL;
    2712             : 
    2713           0 :                 if (ret == -ENOSPC && sbi->s_journal) {
    2714             :                         /*
    2715             :                          * Commit the transaction which would
    2716             :                          * free blocks released in the transaction
    2717             :                          * and try again
    2718             :                          */
    2719           0 :                         jbd2_journal_force_commit_nested(sbi->s_journal);
    2720           0 :                         ret = 0;
    2721           0 :                         continue;
    2722             :                 }
    2723             :                 /* Fatal error - ENOMEM, EIO... */
    2724           0 :                 if (ret)
    2725             :                         break;
    2726             :         }
    2727           0 : unplug:
    2728           0 :         blk_finish_plug(&plug);
    2729           0 :         if (!ret && !cycled && wbc->nr_to_write > 0) {
    2730           0 :                 cycled = 1;
    2731           0 :                 mpd->last_page = writeback_index - 1;
    2732           0 :                 mpd->first_page = 0;
    2733           0 :                 goto retry;
    2734             :         }
    2735             : 
    2736             :         /* Update index */
    2737           0 :         if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
    2738             :                 /*
    2739             :                  * Set the writeback_index so that range_cyclic
    2740             :                  * mode will write it back later
    2741             :                  */
    2742           0 :                 mapping->writeback_index = mpd->first_page;
    2743             : 
    2744           0 : out_writepages:
    2745           0 :         trace_ext4_writepages_result(inode, wbc, ret,
    2746           0 :                                      nr_to_write - wbc->nr_to_write);
    2747           0 :         return ret;
    2748             : }
    2749             : 
    2750           0 : static int ext4_writepages(struct address_space *mapping,
    2751             :                            struct writeback_control *wbc)
    2752             : {
    2753           0 :         struct super_block *sb = mapping->host->i_sb;
    2754           0 :         struct mpage_da_data mpd = {
    2755             :                 .inode = mapping->host,
    2756             :                 .wbc = wbc,
    2757             :                 .can_map = 1,
    2758             :         };
    2759           0 :         int ret;
    2760           0 :         int alloc_ctx;
    2761             : 
    2762           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
    2763             :                 return -EIO;
    2764             : 
    2765           0 :         alloc_ctx = ext4_writepages_down_read(sb);
    2766           0 :         ret = ext4_do_writepages(&mpd);
    2767             :         /*
    2768             :          * For data=journal writeback we could have come across pages marked
    2769             :          * for delayed dirtying (PageChecked) which were just added to the
    2770             :          * running transaction. Try once more to get them to stable storage.
    2771             :          */
    2772           0 :         if (!ret && mpd.journalled_more_data)
    2773           0 :                 ret = ext4_do_writepages(&mpd);
    2774           0 :         ext4_writepages_up_read(sb, alloc_ctx);
    2775             : 
    2776           0 :         return ret;
    2777             : }
    2778             : 
    2779           0 : int ext4_normal_submit_inode_data_buffers(struct jbd2_inode *jinode)
    2780             : {
    2781           0 :         struct writeback_control wbc = {
    2782             :                 .sync_mode = WB_SYNC_ALL,
    2783             :                 .nr_to_write = LONG_MAX,
    2784           0 :                 .range_start = jinode->i_dirty_start,
    2785           0 :                 .range_end = jinode->i_dirty_end,
    2786             :         };
    2787           0 :         struct mpage_da_data mpd = {
    2788           0 :                 .inode = jinode->i_vfs_inode,
    2789             :                 .wbc = &wbc,
    2790             :                 .can_map = 0,
    2791             :         };
    2792           0 :         return ext4_do_writepages(&mpd);
    2793             : }
    2794             : 
    2795             : static int ext4_dax_writepages(struct address_space *mapping,
    2796             :                                struct writeback_control *wbc)
    2797             : {
    2798             :         int ret;
    2799             :         long nr_to_write = wbc->nr_to_write;
    2800             :         struct inode *inode = mapping->host;
    2801             :         struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
    2802             :         int alloc_ctx;
    2803             : 
    2804             :         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
    2805             :                 return -EIO;
    2806             : 
    2807             :         alloc_ctx = ext4_writepages_down_read(inode->i_sb);
    2808             :         trace_ext4_writepages(inode, wbc);
    2809             : 
    2810             :         ret = dax_writeback_mapping_range(mapping, sbi->s_daxdev, wbc);
    2811             :         trace_ext4_writepages_result(inode, wbc, ret,
    2812             :                                      nr_to_write - wbc->nr_to_write);
    2813             :         ext4_writepages_up_read(inode->i_sb, alloc_ctx);
    2814             :         return ret;
    2815             : }
    2816             : 
    2817           0 : static int ext4_nonda_switch(struct super_block *sb)
    2818             : {
    2819           0 :         s64 free_clusters, dirty_clusters;
    2820           0 :         struct ext4_sb_info *sbi = EXT4_SB(sb);
    2821             : 
    2822             :         /*
    2823             :          * switch to non delalloc mode if we are running low
    2824             :          * on free block. The free block accounting via percpu
    2825             :          * counters can get slightly wrong with percpu_counter_batch getting
    2826             :          * accumulated on each CPU without updating global counters
    2827             :          * Delalloc need an accurate free block accounting. So switch
    2828             :          * to non delalloc when we are near to error range.
    2829             :          */
    2830           0 :         free_clusters =
    2831             :                 percpu_counter_read_positive(&sbi->s_freeclusters_counter);
    2832           0 :         dirty_clusters =
    2833             :                 percpu_counter_read_positive(&sbi->s_dirtyclusters_counter);
    2834             :         /*
    2835             :          * Start pushing delalloc when 1/2 of free blocks are dirty.
    2836             :          */
    2837           0 :         if (dirty_clusters && (free_clusters < 2 * dirty_clusters))
    2838           0 :                 try_to_writeback_inodes_sb(sb, WB_REASON_FS_FREE_SPACE);
    2839             : 
    2840           0 :         if (2 * free_clusters < 3 * dirty_clusters ||
    2841           0 :             free_clusters < (dirty_clusters + EXT4_FREECLUSTERS_WATERMARK)) {
    2842             :                 /*
    2843             :                  * free block count is less than 150% of dirty blocks
    2844             :                  * or free blocks is less than watermark
    2845             :                  */
    2846           0 :                 return 1;
    2847             :         }
    2848             :         return 0;
    2849             : }
    2850             : 
    2851           0 : static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
    2852             :                                loff_t pos, unsigned len,
    2853             :                                struct page **pagep, void **fsdata)
    2854             : {
    2855           0 :         int ret, retries = 0;
    2856           0 :         struct folio *folio;
    2857           0 :         pgoff_t index;
    2858           0 :         struct inode *inode = mapping->host;
    2859             : 
    2860           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
    2861             :                 return -EIO;
    2862             : 
    2863           0 :         index = pos >> PAGE_SHIFT;
    2864             : 
    2865           0 :         if (ext4_nonda_switch(inode->i_sb) || ext4_verity_in_progress(inode)) {
    2866           0 :                 *fsdata = (void *)FALL_BACK_TO_NONDELALLOC;
    2867           0 :                 return ext4_write_begin(file, mapping, pos,
    2868             :                                         len, pagep, fsdata);
    2869             :         }
    2870           0 :         *fsdata = (void *)0;
    2871           0 :         trace_ext4_da_write_begin(inode, pos, len);
    2872             : 
    2873           0 :         if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
    2874           0 :                 ret = ext4_da_write_inline_data_begin(mapping, inode, pos, len,
    2875             :                                                       pagep, fsdata);
    2876           0 :                 if (ret < 0)
    2877             :                         return ret;
    2878           0 :                 if (ret == 1)
    2879             :                         return 0;
    2880             :         }
    2881             : 
    2882           0 : retry:
    2883           0 :         folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
    2884             :                         mapping_gfp_mask(mapping));
    2885           0 :         if (IS_ERR(folio))
    2886           0 :                 return PTR_ERR(folio);
    2887             : 
    2888             :         /* In case writeback began while the folio was unlocked */
    2889           0 :         folio_wait_stable(folio);
    2890             : 
    2891             : #ifdef CONFIG_FS_ENCRYPTION
    2892             :         ret = ext4_block_write_begin(folio, pos, len, ext4_da_get_block_prep);
    2893             : #else
    2894           0 :         ret = __block_write_begin(&folio->page, pos, len, ext4_da_get_block_prep);
    2895             : #endif
    2896           0 :         if (ret < 0) {
    2897           0 :                 folio_unlock(folio);
    2898           0 :                 folio_put(folio);
    2899             :                 /*
    2900             :                  * block_write_begin may have instantiated a few blocks
    2901             :                  * outside i_size.  Trim these off again. Don't need
    2902             :                  * i_size_read because we hold inode lock.
    2903             :                  */
    2904           0 :                 if (pos + len > inode->i_size)
    2905           0 :                         ext4_truncate_failed_write(inode);
    2906             : 
    2907           0 :                 if (ret == -ENOSPC &&
    2908           0 :                     ext4_should_retry_alloc(inode->i_sb, &retries))
    2909           0 :                         goto retry;
    2910           0 :                 return ret;
    2911             :         }
    2912             : 
    2913           0 :         *pagep = &folio->page;
    2914           0 :         return ret;
    2915             : }
    2916             : 
    2917             : /*
    2918             :  * Check if we should update i_disksize
    2919             :  * when write to the end of file but not require block allocation
    2920             :  */
    2921           0 : static int ext4_da_should_update_i_disksize(struct folio *folio,
    2922             :                                             unsigned long offset)
    2923             : {
    2924           0 :         struct buffer_head *bh;
    2925           0 :         struct inode *inode = folio->mapping->host;
    2926           0 :         unsigned int idx;
    2927           0 :         int i;
    2928             : 
    2929           0 :         bh = folio_buffers(folio);
    2930           0 :         idx = offset >> inode->i_blkbits;
    2931             : 
    2932           0 :         for (i = 0; i < idx; i++)
    2933           0 :                 bh = bh->b_this_page;
    2934             : 
    2935           0 :         if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh))
    2936           0 :                 return 0;
    2937             :         return 1;
    2938             : }
    2939             : 
    2940           0 : static int ext4_da_write_end(struct file *file,
    2941             :                              struct address_space *mapping,
    2942             :                              loff_t pos, unsigned len, unsigned copied,
    2943             :                              struct page *page, void *fsdata)
    2944             : {
    2945           0 :         struct inode *inode = mapping->host;
    2946           0 :         loff_t new_i_size;
    2947           0 :         unsigned long start, end;
    2948           0 :         int write_mode = (int)(unsigned long)fsdata;
    2949           0 :         struct folio *folio = page_folio(page);
    2950             : 
    2951           0 :         if (write_mode == FALL_BACK_TO_NONDELALLOC)
    2952           0 :                 return ext4_write_end(file, mapping, pos,
    2953             :                                       len, copied, &folio->page, fsdata);
    2954             : 
    2955           0 :         trace_ext4_da_write_end(inode, pos, len, copied);
    2956             : 
    2957           0 :         if (write_mode != CONVERT_INLINE_DATA &&
    2958             :             ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) &&
    2959             :             ext4_has_inline_data(inode))
    2960           0 :                 return ext4_write_inline_data_end(inode, pos, len, copied,
    2961             :                                                   folio);
    2962             : 
    2963           0 :         if (unlikely(copied < len) && !PageUptodate(page))
    2964           0 :                 copied = 0;
    2965             : 
    2966           0 :         start = pos & (PAGE_SIZE - 1);
    2967           0 :         end = start + copied - 1;
    2968             : 
    2969             :         /*
    2970             :          * Since we are holding inode lock, we are sure i_disksize <=
    2971             :          * i_size. We also know that if i_disksize < i_size, there are
    2972             :          * delalloc writes pending in the range upto i_size. If the end of
    2973             :          * the current write is <= i_size, there's no need to touch
    2974             :          * i_disksize since writeback will push i_disksize upto i_size
    2975             :          * eventually. If the end of the current write is > i_size and
    2976             :          * inside an allocated block (ext4_da_should_update_i_disksize()
    2977             :          * check), we need to update i_disksize here as certain
    2978             :          * ext4_writepages() paths not allocating blocks update i_disksize.
    2979             :          *
    2980             :          * Note that we defer inode dirtying to generic_write_end() /
    2981             :          * ext4_da_write_inline_data_end().
    2982             :          */
    2983           0 :         new_i_size = pos + copied;
    2984           0 :         if (copied && new_i_size > inode->i_size &&
    2985           0 :             ext4_da_should_update_i_disksize(folio, end))
    2986           0 :                 ext4_update_i_disksize(inode, new_i_size);
    2987             : 
    2988           0 :         return generic_write_end(file, mapping, pos, len, copied, &folio->page,
    2989             :                                  fsdata);
    2990             : }
    2991             : 
    2992             : /*
    2993             :  * Force all delayed allocation blocks to be allocated for a given inode.
    2994             :  */
    2995           0 : int ext4_alloc_da_blocks(struct inode *inode)
    2996             : {
    2997           0 :         trace_ext4_alloc_da_blocks(inode);
    2998             : 
    2999           0 :         if (!EXT4_I(inode)->i_reserved_data_blocks)
    3000             :                 return 0;
    3001             : 
    3002             :         /*
    3003             :          * We do something simple for now.  The filemap_flush() will
    3004             :          * also start triggering a write of the data blocks, which is
    3005             :          * not strictly speaking necessary (and for users of
    3006             :          * laptop_mode, not even desirable).  However, to do otherwise
    3007             :          * would require replicating code paths in:
    3008             :          *
    3009             :          * ext4_writepages() ->
    3010             :          *    write_cache_pages() ---> (via passed in callback function)
    3011             :          *        __mpage_da_writepage() -->
    3012             :          *           mpage_add_bh_to_extent()
    3013             :          *           mpage_da_map_blocks()
    3014             :          *
    3015             :          * The problem is that write_cache_pages(), located in
    3016             :          * mm/page-writeback.c, marks pages clean in preparation for
    3017             :          * doing I/O, which is not desirable if we're not planning on
    3018             :          * doing I/O at all.
    3019             :          *
    3020             :          * We could call write_cache_pages(), and then redirty all of
    3021             :          * the pages by calling redirty_page_for_writepage() but that
    3022             :          * would be ugly in the extreme.  So instead we would need to
    3023             :          * replicate parts of the code in the above functions,
    3024             :          * simplifying them because we wouldn't actually intend to
    3025             :          * write out the pages, but rather only collect contiguous
    3026             :          * logical block extents, call the multi-block allocator, and
    3027             :          * then update the buffer heads with the block allocations.
    3028             :          *
    3029             :          * For now, though, we'll cheat by calling filemap_flush(),
    3030             :          * which will map the blocks, and start the I/O, but not
    3031             :          * actually wait for the I/O to complete.
    3032             :          */
    3033           0 :         return filemap_flush(inode->i_mapping);
    3034             : }
    3035             : 
    3036             : /*
    3037             :  * bmap() is special.  It gets used by applications such as lilo and by
    3038             :  * the swapper to find the on-disk block of a specific piece of data.
    3039             :  *
    3040             :  * Naturally, this is dangerous if the block concerned is still in the
    3041             :  * journal.  If somebody makes a swapfile on an ext4 data-journaling
    3042             :  * filesystem and enables swap, then they may get a nasty shock when the
    3043             :  * data getting swapped to that swapfile suddenly gets overwritten by
    3044             :  * the original zero's written out previously to the journal and
    3045             :  * awaiting writeback in the kernel's buffer cache.
    3046             :  *
    3047             :  * So, if we see any bmap calls here on a modified, data-journaled file,
    3048             :  * take extra steps to flush any blocks which might be in the cache.
    3049             :  */
    3050           0 : static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
    3051             : {
    3052           0 :         struct inode *inode = mapping->host;
    3053           0 :         sector_t ret = 0;
    3054             : 
    3055           0 :         inode_lock_shared(inode);
    3056             :         /*
    3057             :          * We can get here for an inline file via the FIBMAP ioctl
    3058             :          */
    3059           0 :         if (ext4_has_inline_data(inode))
    3060           0 :                 goto out;
    3061             : 
    3062           0 :         if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) &&
    3063           0 :             (test_opt(inode->i_sb, DELALLOC) ||
    3064             :              ext4_should_journal_data(inode))) {
    3065             :                 /*
    3066             :                  * With delalloc or journalled data we want to sync the file so
    3067             :                  * that we can make sure we allocate blocks for file and data
    3068             :                  * is in place for the user to see it
    3069             :                  */
    3070           0 :                 filemap_write_and_wait(mapping);
    3071             :         }
    3072             : 
    3073           0 :         ret = iomap_bmap(mapping, block, &ext4_iomap_ops);
    3074             : 
    3075           0 : out:
    3076           0 :         inode_unlock_shared(inode);
    3077           0 :         return ret;
    3078             : }
    3079             : 
    3080           0 : static int ext4_read_folio(struct file *file, struct folio *folio)
    3081             : {
    3082           0 :         int ret = -EAGAIN;
    3083           0 :         struct inode *inode = folio->mapping->host;
    3084             : 
    3085           0 :         trace_ext4_read_folio(inode, folio);
    3086             : 
    3087           0 :         if (ext4_has_inline_data(inode))
    3088           0 :                 ret = ext4_readpage_inline(inode, folio);
    3089             : 
    3090           0 :         if (ret == -EAGAIN)
    3091           0 :                 return ext4_mpage_readpages(inode, NULL, folio);
    3092             : 
    3093             :         return ret;
    3094             : }
    3095             : 
    3096           0 : static void ext4_readahead(struct readahead_control *rac)
    3097             : {
    3098           0 :         struct inode *inode = rac->mapping->host;
    3099             : 
    3100             :         /* If the file has inline data, no need to do readahead. */
    3101           0 :         if (ext4_has_inline_data(inode))
    3102             :                 return;
    3103             : 
    3104           0 :         ext4_mpage_readpages(inode, rac, NULL);
    3105             : }
    3106             : 
    3107           0 : static void ext4_invalidate_folio(struct folio *folio, size_t offset,
    3108             :                                 size_t length)
    3109             : {
    3110           0 :         trace_ext4_invalidate_folio(folio, offset, length);
    3111             : 
    3112             :         /* No journalling happens on data buffers when this function is used */
    3113           0 :         WARN_ON(folio_buffers(folio) && buffer_jbd(folio_buffers(folio)));
    3114             : 
    3115           0 :         block_invalidate_folio(folio, offset, length);
    3116           0 : }
    3117             : 
    3118           0 : static int __ext4_journalled_invalidate_folio(struct folio *folio,
    3119             :                                             size_t offset, size_t length)
    3120             : {
    3121           0 :         journal_t *journal = EXT4_JOURNAL(folio->mapping->host);
    3122             : 
    3123           0 :         trace_ext4_journalled_invalidate_folio(folio, offset, length);
    3124             : 
    3125             :         /*
    3126             :          * If it's a full truncate we just forget about the pending dirtying
    3127             :          */
    3128           0 :         if (offset == 0 && length == folio_size(folio))
    3129           0 :                 folio_clear_checked(folio);
    3130             : 
    3131           0 :         return jbd2_journal_invalidate_folio(journal, folio, offset, length);
    3132             : }
    3133             : 
    3134             : /* Wrapper for aops... */
    3135           0 : static void ext4_journalled_invalidate_folio(struct folio *folio,
    3136             :                                            size_t offset,
    3137             :                                            size_t length)
    3138             : {
    3139           0 :         WARN_ON(__ext4_journalled_invalidate_folio(folio, offset, length) < 0);
    3140           0 : }
    3141             : 
    3142           0 : static bool ext4_release_folio(struct folio *folio, gfp_t wait)
    3143             : {
    3144           0 :         struct inode *inode = folio->mapping->host;
    3145           0 :         journal_t *journal = EXT4_JOURNAL(inode);
    3146             : 
    3147           0 :         trace_ext4_release_folio(inode, folio);
    3148             : 
    3149             :         /* Page has dirty journalled data -> cannot release */
    3150           0 :         if (folio_test_checked(folio))
    3151             :                 return false;
    3152           0 :         if (journal)
    3153           0 :                 return jbd2_journal_try_to_free_buffers(journal, folio);
    3154             :         else
    3155           0 :                 return try_to_free_buffers(folio);
    3156             : }
    3157             : 
    3158           0 : static bool ext4_inode_datasync_dirty(struct inode *inode)
    3159             : {
    3160           0 :         journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
    3161             : 
    3162           0 :         if (journal) {
    3163           0 :                 if (jbd2_transaction_committed(journal,
    3164           0 :                         EXT4_I(inode)->i_datasync_tid))
    3165             :                         return false;
    3166           0 :                 if (test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT))
    3167           0 :                         return !list_empty(&EXT4_I(inode)->i_fc_list);
    3168             :                 return true;
    3169             :         }
    3170             : 
    3171             :         /* Any metadata buffers to write? */
    3172           0 :         if (!list_empty(&inode->i_mapping->private_list))
    3173             :                 return true;
    3174           0 :         return inode->i_state & I_DIRTY_DATASYNC;
    3175             : }
    3176             : 
    3177           0 : static void ext4_set_iomap(struct inode *inode, struct iomap *iomap,
    3178             :                            struct ext4_map_blocks *map, loff_t offset,
    3179             :                            loff_t length, unsigned int flags)
    3180             : {
    3181           0 :         u8 blkbits = inode->i_blkbits;
    3182             : 
    3183             :         /*
    3184             :          * Writes that span EOF might trigger an I/O size update on completion,
    3185             :          * so consider them to be dirty for the purpose of O_DSYNC, even if
    3186             :          * there is no other metadata changes being made or are pending.
    3187             :          */
    3188           0 :         iomap->flags = 0;
    3189           0 :         if (ext4_inode_datasync_dirty(inode) ||
    3190           0 :             offset + length > i_size_read(inode))
    3191           0 :                 iomap->flags |= IOMAP_F_DIRTY;
    3192             : 
    3193           0 :         if (map->m_flags & EXT4_MAP_NEW)
    3194           0 :                 iomap->flags |= IOMAP_F_NEW;
    3195             : 
    3196           0 :         if (flags & IOMAP_DAX)
    3197             :                 iomap->dax_dev = EXT4_SB(inode->i_sb)->s_daxdev;
    3198             :         else
    3199           0 :                 iomap->bdev = inode->i_sb->s_bdev;
    3200           0 :         iomap->offset = (u64) map->m_lblk << blkbits;
    3201           0 :         iomap->length = (u64) map->m_len << blkbits;
    3202             : 
    3203           0 :         if ((map->m_flags & EXT4_MAP_MAPPED) &&
    3204             :             !ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    3205           0 :                 iomap->flags |= IOMAP_F_MERGED;
    3206             : 
    3207             :         /*
    3208             :          * Flags passed to ext4_map_blocks() for direct I/O writes can result
    3209             :          * in m_flags having both EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN bits
    3210             :          * set. In order for any allocated unwritten extents to be converted
    3211             :          * into written extents correctly within the ->end_io() handler, we
    3212             :          * need to ensure that the iomap->type is set appropriately. Hence, the
    3213             :          * reason why we need to check whether the EXT4_MAP_UNWRITTEN bit has
    3214             :          * been set first.
    3215             :          */
    3216           0 :         if (map->m_flags & EXT4_MAP_UNWRITTEN) {
    3217           0 :                 iomap->type = IOMAP_UNWRITTEN;
    3218           0 :                 iomap->addr = (u64) map->m_pblk << blkbits;
    3219           0 :                 if (flags & IOMAP_DAX)
    3220             :                         iomap->addr += EXT4_SB(inode->i_sb)->s_dax_part_off;
    3221           0 :         } else if (map->m_flags & EXT4_MAP_MAPPED) {
    3222           0 :                 iomap->type = IOMAP_MAPPED;
    3223           0 :                 iomap->addr = (u64) map->m_pblk << blkbits;
    3224           0 :                 if (flags & IOMAP_DAX)
    3225             :                         iomap->addr += EXT4_SB(inode->i_sb)->s_dax_part_off;
    3226             :         } else {
    3227           0 :                 iomap->type = IOMAP_HOLE;
    3228           0 :                 iomap->addr = IOMAP_NULL_ADDR;
    3229             :         }
    3230           0 : }
    3231             : 
    3232           0 : static int ext4_iomap_alloc(struct inode *inode, struct ext4_map_blocks *map,
    3233             :                             unsigned int flags)
    3234             : {
    3235           0 :         handle_t *handle;
    3236           0 :         u8 blkbits = inode->i_blkbits;
    3237           0 :         int ret, dio_credits, m_flags = 0, retries = 0;
    3238             : 
    3239             :         /*
    3240             :          * Trim the mapping request to the maximum value that we can map at
    3241             :          * once for direct I/O.
    3242             :          */
    3243           0 :         if (map->m_len > DIO_MAX_BLOCKS)
    3244           0 :                 map->m_len = DIO_MAX_BLOCKS;
    3245           0 :         dio_credits = ext4_chunk_trans_blocks(inode, map->m_len);
    3246             : 
    3247           0 : retry:
    3248             :         /*
    3249             :          * Either we allocate blocks and then don't get an unwritten extent, so
    3250             :          * in that case we have reserved enough credits. Or, the blocks are
    3251             :          * already allocated and unwritten. In that case, the extent conversion
    3252             :          * fits into the credits as well.
    3253             :          */
    3254           0 :         handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, dio_credits);
    3255           0 :         if (IS_ERR(handle))
    3256           0 :                 return PTR_ERR(handle);
    3257             : 
    3258             :         /*
    3259             :          * DAX and direct I/O are the only two operations that are currently
    3260             :          * supported with IOMAP_WRITE.
    3261             :          */
    3262           0 :         WARN_ON(!(flags & (IOMAP_DAX | IOMAP_DIRECT)));
    3263           0 :         if (flags & IOMAP_DAX)
    3264             :                 m_flags = EXT4_GET_BLOCKS_CREATE_ZERO;
    3265             :         /*
    3266             :          * We use i_size instead of i_disksize here because delalloc writeback
    3267             :          * can complete at any point during the I/O and subsequently push the
    3268             :          * i_disksize out to i_size. This could be beyond where direct I/O is
    3269             :          * happening and thus expose allocated blocks to direct I/O reads.
    3270             :          */
    3271           0 :         else if (((loff_t)map->m_lblk << blkbits) >= i_size_read(inode))
    3272             :                 m_flags = EXT4_GET_BLOCKS_CREATE;
    3273           0 :         else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    3274           0 :                 m_flags = EXT4_GET_BLOCKS_IO_CREATE_EXT;
    3275             : 
    3276           0 :         ret = ext4_map_blocks(handle, inode, map, m_flags);
    3277             : 
    3278             :         /*
    3279             :          * We cannot fill holes in indirect tree based inodes as that could
    3280             :          * expose stale data in the case of a crash. Use the magic error code
    3281             :          * to fallback to buffered I/O.
    3282             :          */
    3283           0 :         if (!m_flags && !ret)
    3284           0 :                 ret = -ENOTBLK;
    3285             : 
    3286           0 :         ext4_journal_stop(handle);
    3287           0 :         if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
    3288           0 :                 goto retry;
    3289             : 
    3290             :         return ret;
    3291             : }
    3292             : 
    3293             : 
    3294           0 : static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
    3295             :                 unsigned flags, struct iomap *iomap, struct iomap *srcmap)
    3296             : {
    3297           0 :         int ret;
    3298           0 :         struct ext4_map_blocks map;
    3299           0 :         u8 blkbits = inode->i_blkbits;
    3300             : 
    3301           0 :         if ((offset >> blkbits) > EXT4_MAX_LOGICAL_BLOCK)
    3302             :                 return -EINVAL;
    3303             : 
    3304           0 :         if (WARN_ON_ONCE(ext4_has_inline_data(inode)))
    3305             :                 return -ERANGE;
    3306             : 
    3307             :         /*
    3308             :          * Calculate the first and last logical blocks respectively.
    3309             :          */
    3310           0 :         map.m_lblk = offset >> blkbits;
    3311           0 :         map.m_len = min_t(loff_t, (offset + length - 1) >> blkbits,
    3312           0 :                           EXT4_MAX_LOGICAL_BLOCK) - map.m_lblk + 1;
    3313             : 
    3314           0 :         if (flags & IOMAP_WRITE) {
    3315             :                 /*
    3316             :                  * We check here if the blocks are already allocated, then we
    3317             :                  * don't need to start a journal txn and we can directly return
    3318             :                  * the mapping information. This could boost performance
    3319             :                  * especially in multi-threaded overwrite requests.
    3320             :                  */
    3321           0 :                 if (offset + length <= i_size_read(inode)) {
    3322           0 :                         ret = ext4_map_blocks(NULL, inode, &map, 0);
    3323           0 :                         if (ret > 0 && (map.m_flags & EXT4_MAP_MAPPED))
    3324           0 :                                 goto out;
    3325             :                 }
    3326           0 :                 ret = ext4_iomap_alloc(inode, &map, flags);
    3327             :         } else {
    3328           0 :                 ret = ext4_map_blocks(NULL, inode, &map, 0);
    3329             :         }
    3330             : 
    3331           0 :         if (ret < 0)
    3332             :                 return ret;
    3333           0 : out:
    3334             :         /*
    3335             :          * When inline encryption is enabled, sometimes I/O to an encrypted file
    3336             :          * has to be broken up to guarantee DUN contiguity.  Handle this by
    3337             :          * limiting the length of the mapping returned.
    3338             :          */
    3339           0 :         map.m_len = fscrypt_limit_io_blocks(inode, map.m_lblk, map.m_len);
    3340             : 
    3341           0 :         ext4_set_iomap(inode, iomap, &map, offset, length, flags);
    3342             : 
    3343           0 :         return 0;
    3344             : }
    3345             : 
    3346           0 : static int ext4_iomap_overwrite_begin(struct inode *inode, loff_t offset,
    3347             :                 loff_t length, unsigned flags, struct iomap *iomap,
    3348             :                 struct iomap *srcmap)
    3349             : {
    3350           0 :         int ret;
    3351             : 
    3352             :         /*
    3353             :          * Even for writes we don't need to allocate blocks, so just pretend
    3354             :          * we are reading to save overhead of starting a transaction.
    3355             :          */
    3356           0 :         flags &= ~IOMAP_WRITE;
    3357           0 :         ret = ext4_iomap_begin(inode, offset, length, flags, iomap, srcmap);
    3358           0 :         WARN_ON_ONCE(!ret && iomap->type != IOMAP_MAPPED);
    3359           0 :         return ret;
    3360             : }
    3361             : 
    3362           0 : static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length,
    3363             :                           ssize_t written, unsigned flags, struct iomap *iomap)
    3364             : {
    3365             :         /*
    3366             :          * Check to see whether an error occurred while writing out the data to
    3367             :          * the allocated blocks. If so, return the magic error code so that we
    3368             :          * fallback to buffered I/O and attempt to complete the remainder of
    3369             :          * the I/O. Any blocks that may have been allocated in preparation for
    3370             :          * the direct I/O will be reused during buffered I/O.
    3371             :          */
    3372           0 :         if (flags & (IOMAP_WRITE | IOMAP_DIRECT) && written == 0)
    3373           0 :                 return -ENOTBLK;
    3374             : 
    3375             :         return 0;
    3376             : }
    3377             : 
    3378             : const struct iomap_ops ext4_iomap_ops = {
    3379             :         .iomap_begin            = ext4_iomap_begin,
    3380             :         .iomap_end              = ext4_iomap_end,
    3381             : };
    3382             : 
    3383             : const struct iomap_ops ext4_iomap_overwrite_ops = {
    3384             :         .iomap_begin            = ext4_iomap_overwrite_begin,
    3385             :         .iomap_end              = ext4_iomap_end,
    3386             : };
    3387             : 
    3388           0 : static bool ext4_iomap_is_delalloc(struct inode *inode,
    3389             :                                    struct ext4_map_blocks *map)
    3390             : {
    3391           0 :         struct extent_status es;
    3392           0 :         ext4_lblk_t offset = 0, end = map->m_lblk + map->m_len - 1;
    3393             : 
    3394           0 :         ext4_es_find_extent_range(inode, &ext4_es_is_delayed,
    3395             :                                   map->m_lblk, end, &es);
    3396             : 
    3397           0 :         if (!es.es_len || es.es_lblk > end)
    3398             :                 return false;
    3399             : 
    3400           0 :         if (es.es_lblk > map->m_lblk) {
    3401           0 :                 map->m_len = es.es_lblk - map->m_lblk;
    3402           0 :                 return false;
    3403             :         }
    3404             : 
    3405           0 :         offset = map->m_lblk - es.es_lblk;
    3406           0 :         map->m_len = es.es_len - offset;
    3407             : 
    3408           0 :         return true;
    3409             : }
    3410             : 
    3411           0 : static int ext4_iomap_begin_report(struct inode *inode, loff_t offset,
    3412             :                                    loff_t length, unsigned int flags,
    3413             :                                    struct iomap *iomap, struct iomap *srcmap)
    3414             : {
    3415           0 :         int ret;
    3416           0 :         bool delalloc = false;
    3417           0 :         struct ext4_map_blocks map;
    3418           0 :         u8 blkbits = inode->i_blkbits;
    3419             : 
    3420           0 :         if ((offset >> blkbits) > EXT4_MAX_LOGICAL_BLOCK)
    3421             :                 return -EINVAL;
    3422             : 
    3423           0 :         if (ext4_has_inline_data(inode)) {
    3424           0 :                 ret = ext4_inline_data_iomap(inode, iomap);
    3425           0 :                 if (ret != -EAGAIN) {
    3426           0 :                         if (ret == 0 && offset >= iomap->length)
    3427           0 :                                 ret = -ENOENT;
    3428           0 :                         return ret;
    3429             :                 }
    3430             :         }
    3431             : 
    3432             :         /*
    3433             :          * Calculate the first and last logical block respectively.
    3434             :          */
    3435           0 :         map.m_lblk = offset >> blkbits;
    3436           0 :         map.m_len = min_t(loff_t, (offset + length - 1) >> blkbits,
    3437           0 :                           EXT4_MAX_LOGICAL_BLOCK) - map.m_lblk + 1;
    3438             : 
    3439             :         /*
    3440             :          * Fiemap callers may call for offset beyond s_bitmap_maxbytes.
    3441             :          * So handle it here itself instead of querying ext4_map_blocks().
    3442             :          * Since ext4_map_blocks() will warn about it and will return
    3443             :          * -EIO error.
    3444             :          */
    3445           0 :         if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
    3446           0 :                 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    3447             : 
    3448           0 :                 if (offset >= sbi->s_bitmap_maxbytes) {
    3449           0 :                         map.m_flags = 0;
    3450           0 :                         goto set_iomap;
    3451             :                 }
    3452             :         }
    3453             : 
    3454           0 :         ret = ext4_map_blocks(NULL, inode, &map, 0);
    3455           0 :         if (ret < 0)
    3456             :                 return ret;
    3457           0 :         if (ret == 0)
    3458           0 :                 delalloc = ext4_iomap_is_delalloc(inode, &map);
    3459             : 
    3460           0 : set_iomap:
    3461           0 :         ext4_set_iomap(inode, iomap, &map, offset, length, flags);
    3462           0 :         if (delalloc && iomap->type == IOMAP_HOLE)
    3463           0 :                 iomap->type = IOMAP_DELALLOC;
    3464             : 
    3465             :         return 0;
    3466             : }
    3467             : 
    3468             : const struct iomap_ops ext4_iomap_report_ops = {
    3469             :         .iomap_begin = ext4_iomap_begin_report,
    3470             : };
    3471             : 
    3472             : /*
    3473             :  * For data=journal mode, folio should be marked dirty only when it was
    3474             :  * writeably mapped. When that happens, it was already attached to the
    3475             :  * transaction and marked as jbddirty (we take care of this in
    3476             :  * ext4_page_mkwrite()). On transaction commit, we writeprotect page mappings
    3477             :  * so we should have nothing to do here, except for the case when someone
    3478             :  * had the page pinned and dirtied the page through this pin (e.g. by doing
    3479             :  * direct IO to it). In that case we'd need to attach buffers here to the
    3480             :  * transaction but we cannot due to lock ordering.  We cannot just dirty the
    3481             :  * folio and leave attached buffers clean, because the buffers' dirty state is
    3482             :  * "definitive".  We cannot just set the buffers dirty or jbddirty because all
    3483             :  * the journalling code will explode.  So what we do is to mark the folio
    3484             :  * "pending dirty" and next time ext4_writepages() is called, attach buffers
    3485             :  * to the transaction appropriately.
    3486             :  */
    3487           0 : static bool ext4_journalled_dirty_folio(struct address_space *mapping,
    3488             :                 struct folio *folio)
    3489             : {
    3490           0 :         WARN_ON_ONCE(!folio_buffers(folio));
    3491           0 :         if (folio_maybe_dma_pinned(folio))
    3492           0 :                 folio_set_checked(folio);
    3493           0 :         return filemap_dirty_folio(mapping, folio);
    3494             : }
    3495             : 
    3496           0 : static bool ext4_dirty_folio(struct address_space *mapping, struct folio *folio)
    3497             : {
    3498           0 :         WARN_ON_ONCE(!folio_test_locked(folio) && !folio_test_dirty(folio));
    3499           0 :         WARN_ON_ONCE(!folio_buffers(folio));
    3500           0 :         return block_dirty_folio(mapping, folio);
    3501             : }
    3502             : 
    3503           0 : static int ext4_iomap_swap_activate(struct swap_info_struct *sis,
    3504             :                                     struct file *file, sector_t *span)
    3505             : {
    3506           0 :         return iomap_swapfile_activate(sis, file, span,
    3507             :                                        &ext4_iomap_report_ops);
    3508             : }
    3509             : 
    3510             : static const struct address_space_operations ext4_aops = {
    3511             :         .read_folio             = ext4_read_folio,
    3512             :         .readahead              = ext4_readahead,
    3513             :         .writepages             = ext4_writepages,
    3514             :         .write_begin            = ext4_write_begin,
    3515             :         .write_end              = ext4_write_end,
    3516             :         .dirty_folio            = ext4_dirty_folio,
    3517             :         .bmap                   = ext4_bmap,
    3518             :         .invalidate_folio       = ext4_invalidate_folio,
    3519             :         .release_folio          = ext4_release_folio,
    3520             :         .direct_IO              = noop_direct_IO,
    3521             :         .migrate_folio          = buffer_migrate_folio,
    3522             :         .is_partially_uptodate  = block_is_partially_uptodate,
    3523             :         .error_remove_page      = generic_error_remove_page,
    3524             :         .swap_activate          = ext4_iomap_swap_activate,
    3525             : };
    3526             : 
    3527             : static const struct address_space_operations ext4_journalled_aops = {
    3528             :         .read_folio             = ext4_read_folio,
    3529             :         .readahead              = ext4_readahead,
    3530             :         .writepages             = ext4_writepages,
    3531             :         .write_begin            = ext4_write_begin,
    3532             :         .write_end              = ext4_journalled_write_end,
    3533             :         .dirty_folio            = ext4_journalled_dirty_folio,
    3534             :         .bmap                   = ext4_bmap,
    3535             :         .invalidate_folio       = ext4_journalled_invalidate_folio,
    3536             :         .release_folio          = ext4_release_folio,
    3537             :         .direct_IO              = noop_direct_IO,
    3538             :         .migrate_folio          = buffer_migrate_folio_norefs,
    3539             :         .is_partially_uptodate  = block_is_partially_uptodate,
    3540             :         .error_remove_page      = generic_error_remove_page,
    3541             :         .swap_activate          = ext4_iomap_swap_activate,
    3542             : };
    3543             : 
    3544             : static const struct address_space_operations ext4_da_aops = {
    3545             :         .read_folio             = ext4_read_folio,
    3546             :         .readahead              = ext4_readahead,
    3547             :         .writepages             = ext4_writepages,
    3548             :         .write_begin            = ext4_da_write_begin,
    3549             :         .write_end              = ext4_da_write_end,
    3550             :         .dirty_folio            = ext4_dirty_folio,
    3551             :         .bmap                   = ext4_bmap,
    3552             :         .invalidate_folio       = ext4_invalidate_folio,
    3553             :         .release_folio          = ext4_release_folio,
    3554             :         .direct_IO              = noop_direct_IO,
    3555             :         .migrate_folio          = buffer_migrate_folio,
    3556             :         .is_partially_uptodate  = block_is_partially_uptodate,
    3557             :         .error_remove_page      = generic_error_remove_page,
    3558             :         .swap_activate          = ext4_iomap_swap_activate,
    3559             : };
    3560             : 
    3561             : static const struct address_space_operations ext4_dax_aops = {
    3562             :         .writepages             = ext4_dax_writepages,
    3563             :         .direct_IO              = noop_direct_IO,
    3564             :         .dirty_folio            = noop_dirty_folio,
    3565             :         .bmap                   = ext4_bmap,
    3566             :         .swap_activate          = ext4_iomap_swap_activate,
    3567             : };
    3568             : 
    3569           0 : void ext4_set_aops(struct inode *inode)
    3570             : {
    3571           0 :         switch (ext4_inode_journal_mode(inode)) {
    3572             :         case EXT4_INODE_ORDERED_DATA_MODE:
    3573             :         case EXT4_INODE_WRITEBACK_DATA_MODE:
    3574           0 :                 break;
    3575           0 :         case EXT4_INODE_JOURNAL_DATA_MODE:
    3576           0 :                 inode->i_mapping->a_ops = &ext4_journalled_aops;
    3577           0 :                 return;
    3578           0 :         default:
    3579           0 :                 BUG();
    3580             :         }
    3581           0 :         if (IS_DAX(inode))
    3582             :                 inode->i_mapping->a_ops = &ext4_dax_aops;
    3583           0 :         else if (test_opt(inode->i_sb, DELALLOC))
    3584           0 :                 inode->i_mapping->a_ops = &ext4_da_aops;
    3585             :         else
    3586           0 :                 inode->i_mapping->a_ops = &ext4_aops;
    3587             : }
    3588             : 
    3589           0 : static int __ext4_block_zero_page_range(handle_t *handle,
    3590             :                 struct address_space *mapping, loff_t from, loff_t length)
    3591             : {
    3592           0 :         ext4_fsblk_t index = from >> PAGE_SHIFT;
    3593           0 :         unsigned offset = from & (PAGE_SIZE-1);
    3594           0 :         unsigned blocksize, pos;
    3595           0 :         ext4_lblk_t iblock;
    3596           0 :         struct inode *inode = mapping->host;
    3597           0 :         struct buffer_head *bh;
    3598           0 :         struct folio *folio;
    3599           0 :         int err = 0;
    3600             : 
    3601           0 :         folio = __filemap_get_folio(mapping, from >> PAGE_SHIFT,
    3602             :                                     FGP_LOCK | FGP_ACCESSED | FGP_CREAT,
    3603             :                                     mapping_gfp_constraint(mapping, ~__GFP_FS));
    3604           0 :         if (IS_ERR(folio))
    3605           0 :                 return PTR_ERR(folio);
    3606             : 
    3607           0 :         blocksize = inode->i_sb->s_blocksize;
    3608             : 
    3609           0 :         iblock = index << (PAGE_SHIFT - inode->i_sb->s_blocksize_bits);
    3610             : 
    3611           0 :         bh = folio_buffers(folio);
    3612           0 :         if (!bh) {
    3613           0 :                 create_empty_buffers(&folio->page, blocksize, 0);
    3614           0 :                 bh = folio_buffers(folio);
    3615             :         }
    3616             : 
    3617             :         /* Find the buffer that contains "offset" */
    3618           0 :         pos = blocksize;
    3619           0 :         while (offset >= pos) {
    3620           0 :                 bh = bh->b_this_page;
    3621           0 :                 iblock++;
    3622           0 :                 pos += blocksize;
    3623             :         }
    3624           0 :         if (buffer_freed(bh)) {
    3625           0 :                 BUFFER_TRACE(bh, "freed: skip");
    3626           0 :                 goto unlock;
    3627             :         }
    3628           0 :         if (!buffer_mapped(bh)) {
    3629           0 :                 BUFFER_TRACE(bh, "unmapped");
    3630           0 :                 ext4_get_block(inode, iblock, bh, 0);
    3631             :                 /* unmapped? It's a hole - nothing to do */
    3632           0 :                 if (!buffer_mapped(bh)) {
    3633           0 :                         BUFFER_TRACE(bh, "still unmapped");
    3634           0 :                         goto unlock;
    3635             :                 }
    3636             :         }
    3637             : 
    3638             :         /* Ok, it's mapped. Make sure it's up-to-date */
    3639           0 :         if (folio_test_uptodate(folio))
    3640           0 :                 set_buffer_uptodate(bh);
    3641             : 
    3642           0 :         if (!buffer_uptodate(bh)) {
    3643           0 :                 err = ext4_read_bh_lock(bh, 0, true);
    3644           0 :                 if (err)
    3645           0 :                         goto unlock;
    3646             :                 if (fscrypt_inode_uses_fs_layer_crypto(inode)) {
    3647             :                         /* We expect the key to be set. */
    3648             :                         BUG_ON(!fscrypt_has_encryption_key(inode));
    3649             :                         err = fscrypt_decrypt_pagecache_blocks(folio,
    3650             :                                                                blocksize,
    3651             :                                                                bh_offset(bh));
    3652             :                         if (err) {
    3653             :                                 clear_buffer_uptodate(bh);
    3654             :                                 goto unlock;
    3655             :                         }
    3656             :                 }
    3657             :         }
    3658           0 :         if (ext4_should_journal_data(inode)) {
    3659           0 :                 BUFFER_TRACE(bh, "get write access");
    3660           0 :                 err = ext4_journal_get_write_access(handle, inode->i_sb, bh,
    3661             :                                                     EXT4_JTR_NONE);
    3662           0 :                 if (err)
    3663           0 :                         goto unlock;
    3664             :         }
    3665           0 :         folio_zero_range(folio, offset, length);
    3666           0 :         BUFFER_TRACE(bh, "zeroed end of block");
    3667             : 
    3668           0 :         if (ext4_should_journal_data(inode)) {
    3669           0 :                 err = ext4_dirty_journalled_data(handle, bh);
    3670             :         } else {
    3671           0 :                 err = 0;
    3672           0 :                 mark_buffer_dirty(bh);
    3673           0 :                 if (ext4_should_order_data(inode))
    3674           0 :                         err = ext4_jbd2_inode_add_write(handle, inode, from,
    3675             :                                         length);
    3676             :         }
    3677             : 
    3678           0 : unlock:
    3679           0 :         folio_unlock(folio);
    3680           0 :         folio_put(folio);
    3681           0 :         return err;
    3682             : }
    3683             : 
    3684             : /*
    3685             :  * ext4_block_zero_page_range() zeros out a mapping of length 'length'
    3686             :  * starting from file offset 'from'.  The range to be zero'd must
    3687             :  * be contained with in one block.  If the specified range exceeds
    3688             :  * the end of the block it will be shortened to end of the block
    3689             :  * that corresponds to 'from'
    3690             :  */
    3691           0 : static int ext4_block_zero_page_range(handle_t *handle,
    3692             :                 struct address_space *mapping, loff_t from, loff_t length)
    3693             : {
    3694           0 :         struct inode *inode = mapping->host;
    3695           0 :         unsigned offset = from & (PAGE_SIZE-1);
    3696           0 :         unsigned blocksize = inode->i_sb->s_blocksize;
    3697           0 :         unsigned max = blocksize - (offset & (blocksize - 1));
    3698             : 
    3699             :         /*
    3700             :          * correct length if it does not fall between
    3701             :          * 'from' and the end of the block
    3702             :          */
    3703           0 :         if (length > max || length < 0)
    3704           0 :                 length = max;
    3705             : 
    3706           0 :         if (IS_DAX(inode)) {
    3707             :                 return dax_zero_range(inode, from, length, NULL,
    3708             :                                       &ext4_iomap_ops);
    3709             :         }
    3710           0 :         return __ext4_block_zero_page_range(handle, mapping, from, length);
    3711             : }
    3712             : 
    3713             : /*
    3714             :  * ext4_block_truncate_page() zeroes out a mapping from file offset `from'
    3715             :  * up to the end of the block which corresponds to `from'.
    3716             :  * This required during truncate. We need to physically zero the tail end
    3717             :  * of that block so it doesn't yield old data if the file is later grown.
    3718             :  */
    3719           0 : static int ext4_block_truncate_page(handle_t *handle,
    3720             :                 struct address_space *mapping, loff_t from)
    3721             : {
    3722           0 :         unsigned offset = from & (PAGE_SIZE-1);
    3723           0 :         unsigned length;
    3724           0 :         unsigned blocksize;
    3725           0 :         struct inode *inode = mapping->host;
    3726             : 
    3727             :         /* If we are processing an encrypted inode during orphan list handling */
    3728           0 :         if (IS_ENCRYPTED(inode) && !fscrypt_has_encryption_key(inode))
    3729             :                 return 0;
    3730             : 
    3731           0 :         blocksize = inode->i_sb->s_blocksize;
    3732           0 :         length = blocksize - (offset & (blocksize - 1));
    3733             : 
    3734           0 :         return ext4_block_zero_page_range(handle, mapping, from, length);
    3735             : }
    3736             : 
    3737           0 : int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
    3738             :                              loff_t lstart, loff_t length)
    3739             : {
    3740           0 :         struct super_block *sb = inode->i_sb;
    3741           0 :         struct address_space *mapping = inode->i_mapping;
    3742           0 :         unsigned partial_start, partial_end;
    3743           0 :         ext4_fsblk_t start, end;
    3744           0 :         loff_t byte_end = (lstart + length - 1);
    3745           0 :         int err = 0;
    3746             : 
    3747           0 :         partial_start = lstart & (sb->s_blocksize - 1);
    3748           0 :         partial_end = byte_end & (sb->s_blocksize - 1);
    3749             : 
    3750           0 :         start = lstart >> sb->s_blocksize_bits;
    3751           0 :         end = byte_end >> sb->s_blocksize_bits;
    3752             : 
    3753             :         /* Handle partial zero within the single block */
    3754           0 :         if (start == end &&
    3755           0 :             (partial_start || (partial_end != sb->s_blocksize - 1))) {
    3756           0 :                 err = ext4_block_zero_page_range(handle, mapping,
    3757             :                                                  lstart, length);
    3758           0 :                 return err;
    3759             :         }
    3760             :         /* Handle partial zero out on the start of the range */
    3761           0 :         if (partial_start) {
    3762           0 :                 err = ext4_block_zero_page_range(handle, mapping,
    3763             :                                                  lstart, sb->s_blocksize);
    3764           0 :                 if (err)
    3765             :                         return err;
    3766             :         }
    3767             :         /* Handle partial zero out on the end of the range */
    3768           0 :         if (partial_end != sb->s_blocksize - 1)
    3769           0 :                 err = ext4_block_zero_page_range(handle, mapping,
    3770             :                                                  byte_end - partial_end,
    3771           0 :                                                  partial_end + 1);
    3772             :         return err;
    3773             : }
    3774             : 
    3775           0 : int ext4_can_truncate(struct inode *inode)
    3776             : {
    3777           0 :         if (S_ISREG(inode->i_mode))
    3778             :                 return 1;
    3779           0 :         if (S_ISDIR(inode->i_mode))
    3780             :                 return 1;
    3781           0 :         if (S_ISLNK(inode->i_mode))
    3782           0 :                 return !ext4_inode_is_fast_symlink(inode);
    3783             :         return 0;
    3784             : }
    3785             : 
    3786             : /*
    3787             :  * We have to make sure i_disksize gets properly updated before we truncate
    3788             :  * page cache due to hole punching or zero range. Otherwise i_disksize update
    3789             :  * can get lost as it may have been postponed to submission of writeback but
    3790             :  * that will never happen after we truncate page cache.
    3791             :  */
    3792           0 : int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
    3793             :                                       loff_t len)
    3794             : {
    3795           0 :         handle_t *handle;
    3796           0 :         int ret;
    3797             : 
    3798           0 :         loff_t size = i_size_read(inode);
    3799             : 
    3800           0 :         WARN_ON(!inode_is_locked(inode));
    3801           0 :         if (offset > size || offset + len < size)
    3802             :                 return 0;
    3803             : 
    3804           0 :         if (EXT4_I(inode)->i_disksize >= size)
    3805             :                 return 0;
    3806             : 
    3807           0 :         handle = ext4_journal_start(inode, EXT4_HT_MISC, 1);
    3808           0 :         if (IS_ERR(handle))
    3809           0 :                 return PTR_ERR(handle);
    3810           0 :         ext4_update_i_disksize(inode, size);
    3811           0 :         ret = ext4_mark_inode_dirty(handle, inode);
    3812           0 :         ext4_journal_stop(handle);
    3813             : 
    3814           0 :         return ret;
    3815             : }
    3816             : 
    3817             : static void ext4_wait_dax_page(struct inode *inode)
    3818             : {
    3819             :         filemap_invalidate_unlock(inode->i_mapping);
    3820             :         schedule();
    3821             :         filemap_invalidate_lock(inode->i_mapping);
    3822             : }
    3823             : 
    3824           0 : int ext4_break_layouts(struct inode *inode)
    3825             : {
    3826           0 :         struct page *page;
    3827           0 :         int error;
    3828             : 
    3829           0 :         if (WARN_ON_ONCE(!rwsem_is_locked(&inode->i_mapping->invalidate_lock)))
    3830             :                 return -EINVAL;
    3831             : 
    3832           0 :         do {
    3833           0 :                 page = dax_layout_busy_page(inode->i_mapping);
    3834           0 :                 if (!page)
    3835           0 :                         return 0;
    3836             : 
    3837             :                 error = ___wait_var_event(&page->_refcount,
    3838             :                                 atomic_read(&page->_refcount) == 1,
    3839             :                                 TASK_INTERRUPTIBLE, 0, 0,
    3840             :                                 ext4_wait_dax_page(inode));
    3841             :         } while (error == 0);
    3842             : 
    3843             :         return error;
    3844             : }
    3845             : 
    3846             : /*
    3847             :  * ext4_punch_hole: punches a hole in a file by releasing the blocks
    3848             :  * associated with the given offset and length
    3849             :  *
    3850             :  * @inode:  File inode
    3851             :  * @offset: The offset where the hole will begin
    3852             :  * @len:    The length of the hole
    3853             :  *
    3854             :  * Returns: 0 on success or negative on failure
    3855             :  */
    3856             : 
    3857           0 : int ext4_punch_hole(struct file *file, loff_t offset, loff_t length)
    3858             : {
    3859           0 :         struct inode *inode = file_inode(file);
    3860           0 :         struct super_block *sb = inode->i_sb;
    3861           0 :         ext4_lblk_t first_block, stop_block;
    3862           0 :         struct address_space *mapping = inode->i_mapping;
    3863           0 :         loff_t first_block_offset, last_block_offset, max_length;
    3864           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    3865           0 :         handle_t *handle;
    3866           0 :         unsigned int credits;
    3867           0 :         int ret = 0, ret2 = 0;
    3868             : 
    3869           0 :         trace_ext4_punch_hole(inode, offset, length, 0);
    3870             : 
    3871             :         /*
    3872             :          * Write out all dirty pages to avoid race conditions
    3873             :          * Then release them.
    3874             :          */
    3875           0 :         if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
    3876           0 :                 ret = filemap_write_and_wait_range(mapping, offset,
    3877           0 :                                                    offset + length - 1);
    3878           0 :                 if (ret)
    3879             :                         return ret;
    3880             :         }
    3881             : 
    3882           0 :         inode_lock(inode);
    3883             : 
    3884             :         /* No need to punch hole beyond i_size */
    3885           0 :         if (offset >= inode->i_size)
    3886           0 :                 goto out_mutex;
    3887             : 
    3888             :         /*
    3889             :          * If the hole extends beyond i_size, set the hole
    3890             :          * to end after the page that contains i_size
    3891             :          */
    3892           0 :         if (offset + length > inode->i_size) {
    3893           0 :                 length = inode->i_size +
    3894           0 :                    PAGE_SIZE - (inode->i_size & (PAGE_SIZE - 1)) -
    3895             :                    offset;
    3896             :         }
    3897             : 
    3898             :         /*
    3899             :          * For punch hole the length + offset needs to be within one block
    3900             :          * before last range. Adjust the length if it goes beyond that limit.
    3901             :          */
    3902           0 :         max_length = sbi->s_bitmap_maxbytes - inode->i_sb->s_blocksize;
    3903           0 :         if (offset + length > max_length)
    3904           0 :                 length = max_length - offset;
    3905             : 
    3906           0 :         if (offset & (sb->s_blocksize - 1) ||
    3907           0 :             (offset + length) & (sb->s_blocksize - 1)) {
    3908             :                 /*
    3909             :                  * Attach jinode to inode for jbd2 if we do any zeroing of
    3910             :                  * partial block
    3911             :                  */
    3912           0 :                 ret = ext4_inode_attach_jinode(inode);
    3913           0 :                 if (ret < 0)
    3914           0 :                         goto out_mutex;
    3915             : 
    3916             :         }
    3917             : 
    3918             :         /* Wait all existing dio workers, newcomers will block on i_rwsem */
    3919           0 :         inode_dio_wait(inode);
    3920             : 
    3921           0 :         ret = file_modified(file);
    3922           0 :         if (ret)
    3923           0 :                 goto out_mutex;
    3924             : 
    3925             :         /*
    3926             :          * Prevent page faults from reinstantiating pages we have released from
    3927             :          * page cache.
    3928             :          */
    3929           0 :         filemap_invalidate_lock(mapping);
    3930             : 
    3931           0 :         ret = ext4_break_layouts(inode);
    3932           0 :         if (ret)
    3933           0 :                 goto out_dio;
    3934             : 
    3935           0 :         first_block_offset = round_up(offset, sb->s_blocksize);
    3936           0 :         last_block_offset = round_down((offset + length), sb->s_blocksize) - 1;
    3937             : 
    3938             :         /* Now release the pages and zero block aligned part of pages*/
    3939           0 :         if (last_block_offset > first_block_offset) {
    3940           0 :                 ret = ext4_update_disksize_before_punch(inode, offset, length);
    3941           0 :                 if (ret)
    3942           0 :                         goto out_dio;
    3943           0 :                 truncate_pagecache_range(inode, first_block_offset,
    3944             :                                          last_block_offset);
    3945             :         }
    3946             : 
    3947           0 :         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    3948           0 :                 credits = ext4_writepage_trans_blocks(inode);
    3949             :         else
    3950           0 :                 credits = ext4_blocks_for_truncate(inode);
    3951           0 :         handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
    3952           0 :         if (IS_ERR(handle)) {
    3953           0 :                 ret = PTR_ERR(handle);
    3954           0 :                 ext4_std_error(sb, ret);
    3955           0 :                 goto out_dio;
    3956             :         }
    3957             : 
    3958           0 :         ret = ext4_zero_partial_blocks(handle, inode, offset,
    3959             :                                        length);
    3960           0 :         if (ret)
    3961           0 :                 goto out_stop;
    3962             : 
    3963           0 :         first_block = (offset + sb->s_blocksize - 1) >>
    3964           0 :                 EXT4_BLOCK_SIZE_BITS(sb);
    3965           0 :         stop_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb);
    3966             : 
    3967             :         /* If there are blocks to remove, do it */
    3968           0 :         if (stop_block > first_block) {
    3969             : 
    3970           0 :                 down_write(&EXT4_I(inode)->i_data_sem);
    3971           0 :                 ext4_discard_preallocations(inode, 0);
    3972             : 
    3973           0 :                 ext4_es_remove_extent(inode, first_block,
    3974             :                                       stop_block - first_block);
    3975             : 
    3976           0 :                 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    3977           0 :                         ret = ext4_ext_remove_space(inode, first_block,
    3978             :                                                     stop_block - 1);
    3979             :                 else
    3980           0 :                         ret = ext4_ind_remove_space(handle, inode, first_block,
    3981             :                                                     stop_block);
    3982             : 
    3983           0 :                 up_write(&EXT4_I(inode)->i_data_sem);
    3984             :         }
    3985           0 :         ext4_fc_track_range(handle, inode, first_block, stop_block);
    3986           0 :         if (IS_SYNC(inode))
    3987           0 :                 ext4_handle_sync(handle);
    3988             : 
    3989           0 :         inode->i_mtime = inode->i_ctime = current_time(inode);
    3990           0 :         ret2 = ext4_mark_inode_dirty(handle, inode);
    3991           0 :         if (unlikely(ret2))
    3992           0 :                 ret = ret2;
    3993           0 :         if (ret >= 0)
    3994           0 :                 ext4_update_inode_fsync_trans(handle, inode, 1);
    3995           0 : out_stop:
    3996           0 :         ext4_journal_stop(handle);
    3997           0 : out_dio:
    3998           0 :         filemap_invalidate_unlock(mapping);
    3999           0 : out_mutex:
    4000           0 :         inode_unlock(inode);
    4001           0 :         return ret;
    4002             : }
    4003             : 
    4004           0 : int ext4_inode_attach_jinode(struct inode *inode)
    4005             : {
    4006           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    4007           0 :         struct jbd2_inode *jinode;
    4008             : 
    4009           0 :         if (ei->jinode || !EXT4_SB(inode->i_sb)->s_journal)
    4010             :                 return 0;
    4011             : 
    4012           0 :         jinode = jbd2_alloc_inode(GFP_KERNEL);
    4013           0 :         spin_lock(&inode->i_lock);
    4014           0 :         if (!ei->jinode) {
    4015           0 :                 if (!jinode) {
    4016           0 :                         spin_unlock(&inode->i_lock);
    4017           0 :                         return -ENOMEM;
    4018             :                 }
    4019           0 :                 ei->jinode = jinode;
    4020           0 :                 jbd2_journal_init_jbd_inode(ei->jinode, inode);
    4021           0 :                 jinode = NULL;
    4022             :         }
    4023           0 :         spin_unlock(&inode->i_lock);
    4024           0 :         if (unlikely(jinode != NULL))
    4025           0 :                 jbd2_free_inode(jinode);
    4026             :         return 0;
    4027             : }
    4028             : 
    4029             : /*
    4030             :  * ext4_truncate()
    4031             :  *
    4032             :  * We block out ext4_get_block() block instantiations across the entire
    4033             :  * transaction, and VFS/VM ensures that ext4_truncate() cannot run
    4034             :  * simultaneously on behalf of the same inode.
    4035             :  *
    4036             :  * As we work through the truncate and commit bits of it to the journal there
    4037             :  * is one core, guiding principle: the file's tree must always be consistent on
    4038             :  * disk.  We must be able to restart the truncate after a crash.
    4039             :  *
    4040             :  * The file's tree may be transiently inconsistent in memory (although it
    4041             :  * probably isn't), but whenever we close off and commit a journal transaction,
    4042             :  * the contents of (the filesystem + the journal) must be consistent and
    4043             :  * restartable.  It's pretty simple, really: bottom up, right to left (although
    4044             :  * left-to-right works OK too).
    4045             :  *
    4046             :  * Note that at recovery time, journal replay occurs *before* the restart of
    4047             :  * truncate against the orphan inode list.
    4048             :  *
    4049             :  * The committed inode has the new, desired i_size (which is the same as
    4050             :  * i_disksize in this case).  After a crash, ext4_orphan_cleanup() will see
    4051             :  * that this inode's truncate did not complete and it will again call
    4052             :  * ext4_truncate() to have another go.  So there will be instantiated blocks
    4053             :  * to the right of the truncation point in a crashed ext4 filesystem.  But
    4054             :  * that's fine - as long as they are linked from the inode, the post-crash
    4055             :  * ext4_truncate() run will find them and release them.
    4056             :  */
    4057           0 : int ext4_truncate(struct inode *inode)
    4058             : {
    4059           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    4060           0 :         unsigned int credits;
    4061           0 :         int err = 0, err2;
    4062           0 :         handle_t *handle;
    4063           0 :         struct address_space *mapping = inode->i_mapping;
    4064             : 
    4065             :         /*
    4066             :          * There is a possibility that we're either freeing the inode
    4067             :          * or it's a completely new inode. In those cases we might not
    4068             :          * have i_rwsem locked because it's not necessary.
    4069             :          */
    4070           0 :         if (!(inode->i_state & (I_NEW|I_FREEING)))
    4071           0 :                 WARN_ON(!inode_is_locked(inode));
    4072           0 :         trace_ext4_truncate_enter(inode);
    4073             : 
    4074           0 :         if (!ext4_can_truncate(inode))
    4075           0 :                 goto out_trace;
    4076             : 
    4077           0 :         if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
    4078           0 :                 ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
    4079             : 
    4080           0 :         if (ext4_has_inline_data(inode)) {
    4081           0 :                 int has_inline = 1;
    4082             : 
    4083           0 :                 err = ext4_inline_data_truncate(inode, &has_inline);
    4084           0 :                 if (err || has_inline)
    4085           0 :                         goto out_trace;
    4086             :         }
    4087             : 
    4088             :         /* If we zero-out tail of the page, we have to create jinode for jbd2 */
    4089           0 :         if (inode->i_size & (inode->i_sb->s_blocksize - 1)) {
    4090           0 :                 err = ext4_inode_attach_jinode(inode);
    4091           0 :                 if (err)
    4092           0 :                         goto out_trace;
    4093             :         }
    4094             : 
    4095           0 :         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    4096           0 :                 credits = ext4_writepage_trans_blocks(inode);
    4097             :         else
    4098           0 :                 credits = ext4_blocks_for_truncate(inode);
    4099             : 
    4100           0 :         handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
    4101           0 :         if (IS_ERR(handle)) {
    4102           0 :                 err = PTR_ERR(handle);
    4103           0 :                 goto out_trace;
    4104             :         }
    4105             : 
    4106           0 :         if (inode->i_size & (inode->i_sb->s_blocksize - 1))
    4107           0 :                 ext4_block_truncate_page(handle, mapping, inode->i_size);
    4108             : 
    4109             :         /*
    4110             :          * We add the inode to the orphan list, so that if this
    4111             :          * truncate spans multiple transactions, and we crash, we will
    4112             :          * resume the truncate when the filesystem recovers.  It also
    4113             :          * marks the inode dirty, to catch the new size.
    4114             :          *
    4115             :          * Implication: the file must always be in a sane, consistent
    4116             :          * truncatable state while each transaction commits.
    4117             :          */
    4118           0 :         err = ext4_orphan_add(handle, inode);
    4119           0 :         if (err)
    4120           0 :                 goto out_stop;
    4121             : 
    4122           0 :         down_write(&EXT4_I(inode)->i_data_sem);
    4123             : 
    4124           0 :         ext4_discard_preallocations(inode, 0);
    4125             : 
    4126           0 :         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    4127           0 :                 err = ext4_ext_truncate(handle, inode);
    4128             :         else
    4129           0 :                 ext4_ind_truncate(handle, inode);
    4130             : 
    4131           0 :         up_write(&ei->i_data_sem);
    4132           0 :         if (err)
    4133           0 :                 goto out_stop;
    4134             : 
    4135           0 :         if (IS_SYNC(inode))
    4136           0 :                 ext4_handle_sync(handle);
    4137             : 
    4138           0 : out_stop:
    4139             :         /*
    4140             :          * If this was a simple ftruncate() and the file will remain alive,
    4141             :          * then we need to clear up the orphan record which we created above.
    4142             :          * However, if this was a real unlink then we were called by
    4143             :          * ext4_evict_inode(), and we allow that function to clean up the
    4144             :          * orphan info for us.
    4145             :          */
    4146           0 :         if (inode->i_nlink)
    4147           0 :                 ext4_orphan_del(handle, inode);
    4148             : 
    4149           0 :         inode->i_mtime = inode->i_ctime = current_time(inode);
    4150           0 :         err2 = ext4_mark_inode_dirty(handle, inode);
    4151           0 :         if (unlikely(err2 && !err))
    4152           0 :                 err = err2;
    4153           0 :         ext4_journal_stop(handle);
    4154             : 
    4155           0 : out_trace:
    4156           0 :         trace_ext4_truncate_exit(inode);
    4157           0 :         return err;
    4158             : }
    4159             : 
    4160             : static inline u64 ext4_inode_peek_iversion(const struct inode *inode)
    4161             : {
    4162           0 :         if (unlikely(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL))
    4163           0 :                 return inode_peek_iversion_raw(inode);
    4164             :         else
    4165           0 :                 return inode_peek_iversion(inode);
    4166             : }
    4167             : 
    4168           0 : static int ext4_inode_blocks_set(struct ext4_inode *raw_inode,
    4169             :                                  struct ext4_inode_info *ei)
    4170             : {
    4171           0 :         struct inode *inode = &(ei->vfs_inode);
    4172           0 :         u64 i_blocks = READ_ONCE(inode->i_blocks);
    4173           0 :         struct super_block *sb = inode->i_sb;
    4174             : 
    4175           0 :         if (i_blocks <= ~0U) {
    4176             :                 /*
    4177             :                  * i_blocks can be represented in a 32 bit variable
    4178             :                  * as multiple of 512 bytes
    4179             :                  */
    4180           0 :                 raw_inode->i_blocks_lo   = cpu_to_le32(i_blocks);
    4181           0 :                 raw_inode->i_blocks_high = 0;
    4182           0 :                 ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
    4183           0 :                 return 0;
    4184             :         }
    4185             : 
    4186             :         /*
    4187             :          * This should never happen since sb->s_maxbytes should not have
    4188             :          * allowed this, sb->s_maxbytes was set according to the huge_file
    4189             :          * feature in ext4_fill_super().
    4190             :          */
    4191           0 :         if (!ext4_has_feature_huge_file(sb))
    4192             :                 return -EFSCORRUPTED;
    4193             : 
    4194           0 :         if (i_blocks <= 0xffffffffffffULL) {
    4195             :                 /*
    4196             :                  * i_blocks can be represented in a 48 bit variable
    4197             :                  * as multiple of 512 bytes
    4198             :                  */
    4199           0 :                 raw_inode->i_blocks_lo   = cpu_to_le32(i_blocks);
    4200           0 :                 raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
    4201           0 :                 ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
    4202             :         } else {
    4203           0 :                 ext4_set_inode_flag(inode, EXT4_INODE_HUGE_FILE);
    4204             :                 /* i_block is stored in file system block size */
    4205           0 :                 i_blocks = i_blocks >> (inode->i_blkbits - 9);
    4206           0 :                 raw_inode->i_blocks_lo   = cpu_to_le32(i_blocks);
    4207           0 :                 raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
    4208             :         }
    4209             :         return 0;
    4210             : }
    4211             : 
    4212           0 : static int ext4_fill_raw_inode(struct inode *inode, struct ext4_inode *raw_inode)
    4213             : {
    4214           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    4215           0 :         uid_t i_uid;
    4216           0 :         gid_t i_gid;
    4217           0 :         projid_t i_projid;
    4218           0 :         int block;
    4219           0 :         int err;
    4220             : 
    4221           0 :         err = ext4_inode_blocks_set(raw_inode, ei);
    4222             : 
    4223           0 :         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
    4224           0 :         i_uid = i_uid_read(inode);
    4225           0 :         i_gid = i_gid_read(inode);
    4226           0 :         i_projid = from_kprojid(&init_user_ns, ei->i_projid);
    4227           0 :         if (!(test_opt(inode->i_sb, NO_UID32))) {
    4228           0 :                 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
    4229           0 :                 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
    4230             :                 /*
    4231             :                  * Fix up interoperability with old kernels. Otherwise,
    4232             :                  * old inodes get re-used with the upper 16 bits of the
    4233             :                  * uid/gid intact.
    4234             :                  */
    4235           0 :                 if (ei->i_dtime && list_empty(&ei->i_orphan)) {
    4236           0 :                         raw_inode->i_uid_high = 0;
    4237           0 :                         raw_inode->i_gid_high = 0;
    4238             :                 } else {
    4239           0 :                         raw_inode->i_uid_high =
    4240           0 :                                 cpu_to_le16(high_16_bits(i_uid));
    4241           0 :                         raw_inode->i_gid_high =
    4242           0 :                                 cpu_to_le16(high_16_bits(i_gid));
    4243             :                 }
    4244             :         } else {
    4245           0 :                 raw_inode->i_uid_low = cpu_to_le16(fs_high2lowuid(i_uid));
    4246           0 :                 raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(i_gid));
    4247           0 :                 raw_inode->i_uid_high = 0;
    4248           0 :                 raw_inode->i_gid_high = 0;
    4249             :         }
    4250           0 :         raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
    4251             : 
    4252           0 :         EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode);
    4253           0 :         EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode);
    4254           0 :         EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
    4255           0 :         EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode);
    4256             : 
    4257           0 :         raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
    4258           0 :         raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF);
    4259           0 :         if (likely(!test_opt2(inode->i_sb, HURD_COMPAT)))
    4260           0 :                 raw_inode->i_file_acl_high =
    4261           0 :                         cpu_to_le16(ei->i_file_acl >> 32);
    4262           0 :         raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl);
    4263           0 :         ext4_isize_set(raw_inode, ei->i_disksize);
    4264             : 
    4265           0 :         raw_inode->i_generation = cpu_to_le32(inode->i_generation);
    4266           0 :         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
    4267           0 :                 if (old_valid_dev(inode->i_rdev)) {
    4268           0 :                         raw_inode->i_block[0] =
    4269           0 :                                 cpu_to_le32(old_encode_dev(inode->i_rdev));
    4270           0 :                         raw_inode->i_block[1] = 0;
    4271             :                 } else {
    4272           0 :                         raw_inode->i_block[0] = 0;
    4273           0 :                         raw_inode->i_block[1] =
    4274           0 :                                 cpu_to_le32(new_encode_dev(inode->i_rdev));
    4275           0 :                         raw_inode->i_block[2] = 0;
    4276             :                 }
    4277           0 :         } else if (!ext4_has_inline_data(inode)) {
    4278           0 :                 for (block = 0; block < EXT4_N_BLOCKS; block++)
    4279           0 :                         raw_inode->i_block[block] = ei->i_data[block];
    4280             :         }
    4281             : 
    4282           0 :         if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) {
    4283           0 :                 u64 ivers = ext4_inode_peek_iversion(inode);
    4284             : 
    4285           0 :                 raw_inode->i_disk_version = cpu_to_le32(ivers);
    4286           0 :                 if (ei->i_extra_isize) {
    4287           0 :                         if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
    4288           0 :                                 raw_inode->i_version_hi =
    4289           0 :                                         cpu_to_le32(ivers >> 32);
    4290           0 :                         raw_inode->i_extra_isize =
    4291           0 :                                 cpu_to_le16(ei->i_extra_isize);
    4292             :                 }
    4293             :         }
    4294             : 
    4295           0 :         if (i_projid != EXT4_DEF_PROJID &&
    4296           0 :             !ext4_has_feature_project(inode->i_sb))
    4297           0 :                 err = err ?: -EFSCORRUPTED;
    4298             : 
    4299           0 :         if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
    4300           0 :             EXT4_FITS_IN_INODE(raw_inode, ei, i_projid))
    4301           0 :                 raw_inode->i_projid = cpu_to_le32(i_projid);
    4302             : 
    4303           0 :         ext4_inode_csum_set(inode, raw_inode, ei);
    4304           0 :         return err;
    4305             : }
    4306             : 
    4307             : /*
    4308             :  * ext4_get_inode_loc returns with an extra refcount against the inode's
    4309             :  * underlying buffer_head on success. If we pass 'inode' and it does not
    4310             :  * have in-inode xattr, we have all inode data in memory that is needed
    4311             :  * to recreate the on-disk version of this inode.
    4312             :  */
    4313           0 : static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino,
    4314             :                                 struct inode *inode, struct ext4_iloc *iloc,
    4315             :                                 ext4_fsblk_t *ret_block)
    4316             : {
    4317           0 :         struct ext4_group_desc  *gdp;
    4318           0 :         struct buffer_head      *bh;
    4319           0 :         ext4_fsblk_t            block;
    4320           0 :         struct blk_plug         plug;
    4321           0 :         int                     inodes_per_block, inode_offset;
    4322             : 
    4323           0 :         iloc->bh = NULL;
    4324           0 :         if (ino < EXT4_ROOT_INO ||
    4325           0 :             ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
    4326             :                 return -EFSCORRUPTED;
    4327             : 
    4328           0 :         iloc->block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
    4329           0 :         gdp = ext4_get_group_desc(sb, iloc->block_group, NULL);
    4330           0 :         if (!gdp)
    4331             :                 return -EIO;
    4332             : 
    4333             :         /*
    4334             :          * Figure out the offset within the block group inode table
    4335             :          */
    4336           0 :         inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
    4337           0 :         inode_offset = ((ino - 1) %
    4338           0 :                         EXT4_INODES_PER_GROUP(sb));
    4339           0 :         iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb);
    4340             : 
    4341           0 :         block = ext4_inode_table(sb, gdp);
    4342           0 :         if ((block <= le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) ||
    4343             :             (block >= ext4_blocks_count(EXT4_SB(sb)->s_es))) {
    4344           0 :                 ext4_error(sb, "Invalid inode table block %llu in "
    4345             :                            "block_group %u", block, iloc->block_group);
    4346           0 :                 return -EFSCORRUPTED;
    4347             :         }
    4348           0 :         block += (inode_offset / inodes_per_block);
    4349             : 
    4350           0 :         bh = sb_getblk(sb, block);
    4351           0 :         if (unlikely(!bh))
    4352             :                 return -ENOMEM;
    4353           0 :         if (ext4_buffer_uptodate(bh))
    4354           0 :                 goto has_buffer;
    4355             : 
    4356           0 :         lock_buffer(bh);
    4357           0 :         if (ext4_buffer_uptodate(bh)) {
    4358             :                 /* Someone brought it uptodate while we waited */
    4359           0 :                 unlock_buffer(bh);
    4360           0 :                 goto has_buffer;
    4361             :         }
    4362             : 
    4363             :         /*
    4364             :          * If we have all information of the inode in memory and this
    4365             :          * is the only valid inode in the block, we need not read the
    4366             :          * block.
    4367             :          */
    4368           0 :         if (inode && !ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
    4369           0 :                 struct buffer_head *bitmap_bh;
    4370           0 :                 int i, start;
    4371             : 
    4372           0 :                 start = inode_offset & ~(inodes_per_block - 1);
    4373             : 
    4374             :                 /* Is the inode bitmap in cache? */
    4375           0 :                 bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp));
    4376           0 :                 if (unlikely(!bitmap_bh))
    4377           0 :                         goto make_io;
    4378             : 
    4379             :                 /*
    4380             :                  * If the inode bitmap isn't in cache then the
    4381             :                  * optimisation may end up performing two reads instead
    4382             :                  * of one, so skip it.
    4383             :                  */
    4384           0 :                 if (!buffer_uptodate(bitmap_bh)) {
    4385           0 :                         brelse(bitmap_bh);
    4386           0 :                         goto make_io;
    4387             :                 }
    4388           0 :                 for (i = start; i < start + inodes_per_block; i++) {
    4389           0 :                         if (i == inode_offset)
    4390           0 :                                 continue;
    4391           0 :                         if (ext4_test_bit(i, bitmap_bh->b_data))
    4392             :                                 break;
    4393             :                 }
    4394           0 :                 brelse(bitmap_bh);
    4395           0 :                 if (i == start + inodes_per_block) {
    4396           0 :                         struct ext4_inode *raw_inode =
    4397           0 :                                 (struct ext4_inode *) (bh->b_data + iloc->offset);
    4398             : 
    4399             :                         /* all other inodes are free, so skip I/O */
    4400           0 :                         memset(bh->b_data, 0, bh->b_size);
    4401           0 :                         if (!ext4_test_inode_state(inode, EXT4_STATE_NEW))
    4402           0 :                                 ext4_fill_raw_inode(inode, raw_inode);
    4403           0 :                         set_buffer_uptodate(bh);
    4404           0 :                         unlock_buffer(bh);
    4405           0 :                         goto has_buffer;
    4406             :                 }
    4407             :         }
    4408             : 
    4409           0 : make_io:
    4410             :         /*
    4411             :          * If we need to do any I/O, try to pre-readahead extra
    4412             :          * blocks from the inode table.
    4413             :          */
    4414           0 :         blk_start_plug(&plug);
    4415           0 :         if (EXT4_SB(sb)->s_inode_readahead_blks) {
    4416           0 :                 ext4_fsblk_t b, end, table;
    4417           0 :                 unsigned num;
    4418           0 :                 __u32 ra_blks = EXT4_SB(sb)->s_inode_readahead_blks;
    4419             : 
    4420           0 :                 table = ext4_inode_table(sb, gdp);
    4421             :                 /* s_inode_readahead_blks is always a power of 2 */
    4422           0 :                 b = block & ~((ext4_fsblk_t) ra_blks - 1);
    4423           0 :                 if (table > b)
    4424             :                         b = table;
    4425           0 :                 end = b + ra_blks;
    4426           0 :                 num = EXT4_INODES_PER_GROUP(sb);
    4427           0 :                 if (ext4_has_group_desc_csum(sb))
    4428           0 :                         num -= ext4_itable_unused_count(sb, gdp);
    4429           0 :                 table += num / inodes_per_block;
    4430           0 :                 if (end > table)
    4431             :                         end = table;
    4432           0 :                 while (b <= end)
    4433           0 :                         ext4_sb_breadahead_unmovable(sb, b++);
    4434             :         }
    4435             : 
    4436             :         /*
    4437             :          * There are other valid inodes in the buffer, this inode
    4438             :          * has in-inode xattrs, or we don't have this inode in memory.
    4439             :          * Read the block from disk.
    4440             :          */
    4441           0 :         trace_ext4_load_inode(sb, ino);
    4442           0 :         ext4_read_bh_nowait(bh, REQ_META | REQ_PRIO, NULL);
    4443           0 :         blk_finish_plug(&plug);
    4444           0 :         wait_on_buffer(bh);
    4445           0 :         ext4_simulate_fail_bh(sb, bh, EXT4_SIM_INODE_EIO);
    4446           0 :         if (!buffer_uptodate(bh)) {
    4447           0 :                 if (ret_block)
    4448           0 :                         *ret_block = block;
    4449           0 :                 brelse(bh);
    4450           0 :                 return -EIO;
    4451             :         }
    4452           0 : has_buffer:
    4453           0 :         iloc->bh = bh;
    4454           0 :         return 0;
    4455             : }
    4456             : 
    4457           0 : static int __ext4_get_inode_loc_noinmem(struct inode *inode,
    4458             :                                         struct ext4_iloc *iloc)
    4459             : {
    4460           0 :         ext4_fsblk_t err_blk = 0;
    4461           0 :         int ret;
    4462             : 
    4463           0 :         ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, NULL, iloc,
    4464             :                                         &err_blk);
    4465             : 
    4466           0 :         if (ret == -EIO)
    4467           0 :                 ext4_error_inode_block(inode, err_blk, EIO,
    4468             :                                         "unable to read itable block");
    4469             : 
    4470           0 :         return ret;
    4471             : }
    4472             : 
    4473           0 : int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc)
    4474             : {
    4475           0 :         ext4_fsblk_t err_blk = 0;
    4476           0 :         int ret;
    4477             : 
    4478           0 :         ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, inode, iloc,
    4479             :                                         &err_blk);
    4480             : 
    4481           0 :         if (ret == -EIO)
    4482           0 :                 ext4_error_inode_block(inode, err_blk, EIO,
    4483             :                                         "unable to read itable block");
    4484             : 
    4485           0 :         return ret;
    4486             : }
    4487             : 
    4488             : 
    4489           0 : int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino,
    4490             :                           struct ext4_iloc *iloc)
    4491             : {
    4492           0 :         return __ext4_get_inode_loc(sb, ino, NULL, iloc, NULL);
    4493             : }
    4494             : 
    4495           0 : static bool ext4_should_enable_dax(struct inode *inode)
    4496             : {
    4497           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    4498             : 
    4499           0 :         if (test_opt2(inode->i_sb, DAX_NEVER))
    4500             :                 return false;
    4501           0 :         if (!S_ISREG(inode->i_mode))
    4502             :                 return false;
    4503           0 :         if (ext4_should_journal_data(inode))
    4504             :                 return false;
    4505           0 :         if (ext4_has_inline_data(inode))
    4506             :                 return false;
    4507           0 :         if (ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT))
    4508             :                 return false;
    4509           0 :         if (ext4_test_inode_flag(inode, EXT4_INODE_VERITY))
    4510             :                 return false;
    4511           0 :         if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags))
    4512             :                 return false;
    4513           0 :         if (test_opt(inode->i_sb, DAX_ALWAYS))
    4514             :                 return true;
    4515             : 
    4516           0 :         return ext4_test_inode_flag(inode, EXT4_INODE_DAX);
    4517             : }
    4518             : 
    4519           0 : void ext4_set_inode_flags(struct inode *inode, bool init)
    4520             : {
    4521           0 :         unsigned int flags = EXT4_I(inode)->i_flags;
    4522           0 :         unsigned int new_fl = 0;
    4523             : 
    4524           0 :         WARN_ON_ONCE(IS_DAX(inode) && init);
    4525             : 
    4526           0 :         if (flags & EXT4_SYNC_FL)
    4527           0 :                 new_fl |= S_SYNC;
    4528           0 :         if (flags & EXT4_APPEND_FL)
    4529           0 :                 new_fl |= S_APPEND;
    4530           0 :         if (flags & EXT4_IMMUTABLE_FL)
    4531           0 :                 new_fl |= S_IMMUTABLE;
    4532           0 :         if (flags & EXT4_NOATIME_FL)
    4533           0 :                 new_fl |= S_NOATIME;
    4534           0 :         if (flags & EXT4_DIRSYNC_FL)
    4535           0 :                 new_fl |= S_DIRSYNC;
    4536             : 
    4537             :         /* Because of the way inode_set_flags() works we must preserve S_DAX
    4538             :          * here if already set. */
    4539           0 :         new_fl |= (inode->i_flags & S_DAX);
    4540           0 :         if (init && ext4_should_enable_dax(inode))
    4541             :                 new_fl |= S_DAX;
    4542             : 
    4543           0 :         if (flags & EXT4_ENCRYPT_FL)
    4544           0 :                 new_fl |= S_ENCRYPTED;
    4545           0 :         if (flags & EXT4_CASEFOLD_FL)
    4546           0 :                 new_fl |= S_CASEFOLD;
    4547           0 :         if (flags & EXT4_VERITY_FL)
    4548           0 :                 new_fl |= S_VERITY;
    4549           0 :         inode_set_flags(inode, new_fl,
    4550             :                         S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_DAX|
    4551             :                         S_ENCRYPTED|S_CASEFOLD|S_VERITY);
    4552           0 : }
    4553             : 
    4554           0 : static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
    4555             :                                   struct ext4_inode_info *ei)
    4556             : {
    4557           0 :         blkcnt_t i_blocks ;
    4558           0 :         struct inode *inode = &(ei->vfs_inode);
    4559           0 :         struct super_block *sb = inode->i_sb;
    4560             : 
    4561           0 :         if (ext4_has_feature_huge_file(sb)) {
    4562             :                 /* we are using combined 48 bit field */
    4563           0 :                 i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 |
    4564           0 :                                         le32_to_cpu(raw_inode->i_blocks_lo);
    4565           0 :                 if (ext4_test_inode_flag(inode, EXT4_INODE_HUGE_FILE)) {
    4566             :                         /* i_blocks represent file system block size */
    4567           0 :                         return i_blocks  << (inode->i_blkbits - 9);
    4568             :                 } else {
    4569             :                         return i_blocks;
    4570             :                 }
    4571             :         } else {
    4572           0 :                 return le32_to_cpu(raw_inode->i_blocks_lo);
    4573             :         }
    4574             : }
    4575             : 
    4576           0 : static inline int ext4_iget_extra_inode(struct inode *inode,
    4577             :                                          struct ext4_inode *raw_inode,
    4578             :                                          struct ext4_inode_info *ei)
    4579             : {
    4580           0 :         __le32 *magic = (void *)raw_inode +
    4581           0 :                         EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize;
    4582             : 
    4583           0 :         if (EXT4_INODE_HAS_XATTR_SPACE(inode)  &&
    4584           0 :             *magic == cpu_to_le32(EXT4_XATTR_MAGIC)) {
    4585           0 :                 int err;
    4586             : 
    4587           0 :                 ext4_set_inode_state(inode, EXT4_STATE_XATTR);
    4588           0 :                 err = ext4_find_inline_data_nolock(inode);
    4589           0 :                 if (!err && ext4_has_inline_data(inode))
    4590           0 :                         ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
    4591           0 :                 return err;
    4592             :         } else
    4593           0 :                 EXT4_I(inode)->i_inline_off = 0;
    4594           0 :         return 0;
    4595             : }
    4596             : 
    4597           0 : int ext4_get_projid(struct inode *inode, kprojid_t *projid)
    4598             : {
    4599           0 :         if (!ext4_has_feature_project(inode->i_sb))
    4600             :                 return -EOPNOTSUPP;
    4601           0 :         *projid = EXT4_I(inode)->i_projid;
    4602           0 :         return 0;
    4603             : }
    4604             : 
    4605             : /*
    4606             :  * ext4 has self-managed i_version for ea inodes, it stores the lower 32bit of
    4607             :  * refcount in i_version, so use raw values if inode has EXT4_EA_INODE_FL flag
    4608             :  * set.
    4609             :  */
    4610             : static inline void ext4_inode_set_iversion_queried(struct inode *inode, u64 val)
    4611             : {
    4612           0 :         if (unlikely(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL))
    4613           0 :                 inode_set_iversion_raw(inode, val);
    4614             :         else
    4615           0 :                 inode_set_iversion_queried(inode, val);
    4616             : }
    4617             : 
    4618           0 : static const char *check_igot_inode(struct inode *inode, ext4_iget_flags flags)
    4619             : 
    4620             : {
    4621           0 :         if (flags & EXT4_IGET_EA_INODE) {
    4622           0 :                 if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL))
    4623             :                         return "missing EA_INODE flag";
    4624           0 :                 if (ext4_test_inode_state(inode, EXT4_STATE_XATTR) ||
    4625           0 :                     EXT4_I(inode)->i_file_acl)
    4626             :                         return "ea_inode with extended attributes";
    4627             :         } else {
    4628           0 :                 if ((EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL))
    4629             :                         return "unexpected EA_INODE flag";
    4630             :         }
    4631           0 :         if (is_bad_inode(inode) && !(flags & EXT4_IGET_BAD))
    4632           0 :                 return "unexpected bad inode w/o EXT4_IGET_BAD";
    4633             :         return NULL;
    4634             : }
    4635             : 
    4636           0 : struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
    4637             :                           ext4_iget_flags flags, const char *function,
    4638             :                           unsigned int line)
    4639             : {
    4640           0 :         struct ext4_iloc iloc;
    4641           0 :         struct ext4_inode *raw_inode;
    4642           0 :         struct ext4_inode_info *ei;
    4643           0 :         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
    4644           0 :         struct inode *inode;
    4645           0 :         const char *err_str;
    4646           0 :         journal_t *journal = EXT4_SB(sb)->s_journal;
    4647           0 :         long ret;
    4648           0 :         loff_t size;
    4649           0 :         int block;
    4650           0 :         uid_t i_uid;
    4651           0 :         gid_t i_gid;
    4652           0 :         projid_t i_projid;
    4653             : 
    4654           0 :         if ((!(flags & EXT4_IGET_SPECIAL) &&
    4655           0 :              ((ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO) ||
    4656           0 :               ino == le32_to_cpu(es->s_usr_quota_inum) ||
    4657           0 :               ino == le32_to_cpu(es->s_grp_quota_inum) ||
    4658           0 :               ino == le32_to_cpu(es->s_prj_quota_inum) ||
    4659           0 :               ino == le32_to_cpu(es->s_orphan_file_inum))) ||
    4660           0 :             (ino < EXT4_ROOT_INO) ||
    4661           0 :             (ino > le32_to_cpu(es->s_inodes_count))) {
    4662           0 :                 if (flags & EXT4_IGET_HANDLE)
    4663             :                         return ERR_PTR(-ESTALE);
    4664           0 :                 __ext4_error(sb, function, line, false, EFSCORRUPTED, 0,
    4665             :                              "inode #%lu: comm %s: iget: illegal inode #",
    4666           0 :                              ino, current->comm);
    4667           0 :                 return ERR_PTR(-EFSCORRUPTED);
    4668             :         }
    4669             : 
    4670           0 :         inode = iget_locked(sb, ino);
    4671           0 :         if (!inode)
    4672             :                 return ERR_PTR(-ENOMEM);
    4673           0 :         if (!(inode->i_state & I_NEW)) {
    4674           0 :                 if ((err_str = check_igot_inode(inode, flags)) != NULL) {
    4675           0 :                         ext4_error_inode(inode, function, line, 0, err_str);
    4676           0 :                         iput(inode);
    4677           0 :                         return ERR_PTR(-EFSCORRUPTED);
    4678             :                 }
    4679             :                 return inode;
    4680             :         }
    4681             : 
    4682           0 :         ei = EXT4_I(inode);
    4683           0 :         iloc.bh = NULL;
    4684             : 
    4685           0 :         ret = __ext4_get_inode_loc_noinmem(inode, &iloc);
    4686           0 :         if (ret < 0)
    4687           0 :                 goto bad_inode;
    4688           0 :         raw_inode = ext4_raw_inode(&iloc);
    4689             : 
    4690           0 :         if ((flags & EXT4_IGET_HANDLE) &&
    4691           0 :             (raw_inode->i_links_count == 0) && (raw_inode->i_mode == 0)) {
    4692           0 :                 ret = -ESTALE;
    4693           0 :                 goto bad_inode;
    4694             :         }
    4695             : 
    4696           0 :         if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
    4697           0 :                 ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
    4698           0 :                 if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
    4699           0 :                         EXT4_INODE_SIZE(inode->i_sb) ||
    4700             :                     (ei->i_extra_isize & 3)) {
    4701           0 :                         ext4_error_inode(inode, function, line, 0,
    4702             :                                          "iget: bad extra_isize %u "
    4703             :                                          "(inode size %u)",
    4704             :                                          ei->i_extra_isize,
    4705             :                                          EXT4_INODE_SIZE(inode->i_sb));
    4706           0 :                         ret = -EFSCORRUPTED;
    4707           0 :                         goto bad_inode;
    4708             :                 }
    4709             :         } else
    4710           0 :                 ei->i_extra_isize = 0;
    4711             : 
    4712             :         /* Precompute checksum seed for inode metadata */
    4713           0 :         if (ext4_has_metadata_csum(sb)) {
    4714           0 :                 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    4715           0 :                 __u32 csum;
    4716           0 :                 __le32 inum = cpu_to_le32(inode->i_ino);
    4717           0 :                 __le32 gen = raw_inode->i_generation;
    4718           0 :                 csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&inum,
    4719             :                                    sizeof(inum));
    4720           0 :                 ei->i_csum_seed = ext4_chksum(sbi, csum, (__u8 *)&gen,
    4721             :                                               sizeof(gen));
    4722             :         }
    4723             : 
    4724           0 :         if ((!ext4_inode_csum_verify(inode, raw_inode, ei) ||
    4725           0 :             ext4_simulate_fail(sb, EXT4_SIM_INODE_CRC)) &&
    4726           0 :              (!(EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))) {
    4727           0 :                 ext4_error_inode_err(inode, function, line, 0,
    4728             :                                 EFSBADCRC, "iget: checksum invalid");
    4729           0 :                 ret = -EFSBADCRC;
    4730           0 :                 goto bad_inode;
    4731             :         }
    4732             : 
    4733           0 :         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
    4734           0 :         i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
    4735           0 :         i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
    4736           0 :         if (ext4_has_feature_project(sb) &&
    4737           0 :             EXT4_INODE_SIZE(sb) > EXT4_GOOD_OLD_INODE_SIZE &&
    4738           0 :             EXT4_FITS_IN_INODE(raw_inode, ei, i_projid))
    4739           0 :                 i_projid = (projid_t)le32_to_cpu(raw_inode->i_projid);
    4740             :         else
    4741             :                 i_projid = EXT4_DEF_PROJID;
    4742             : 
    4743           0 :         if (!(test_opt(inode->i_sb, NO_UID32))) {
    4744           0 :                 i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
    4745           0 :                 i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
    4746             :         }
    4747           0 :         i_uid_write(inode, i_uid);
    4748           0 :         i_gid_write(inode, i_gid);
    4749           0 :         ei->i_projid = make_kprojid(&init_user_ns, i_projid);
    4750           0 :         set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
    4751             : 
    4752           0 :         ext4_clear_state_flags(ei);     /* Only relevant on 32-bit archs */
    4753           0 :         ei->i_inline_off = 0;
    4754           0 :         ei->i_dir_start_lookup = 0;
    4755           0 :         ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
    4756             :         /* We now have enough fields to check if the inode was active or not.
    4757             :          * This is needed because nfsd might try to access dead inodes
    4758             :          * the test is that same one that e2fsck uses
    4759             :          * NeilBrown 1999oct15
    4760             :          */
    4761           0 :         if (inode->i_nlink == 0) {
    4762           0 :                 if ((inode->i_mode == 0 || flags & EXT4_IGET_SPECIAL ||
    4763           0 :                      !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) &&
    4764             :                     ino != EXT4_BOOT_LOADER_INO) {
    4765             :                         /* this inode is deleted or unallocated */
    4766           0 :                         if (flags & EXT4_IGET_SPECIAL) {
    4767           0 :                                 ext4_error_inode(inode, function, line, 0,
    4768             :                                                  "iget: special inode unallocated");
    4769           0 :                                 ret = -EFSCORRUPTED;
    4770             :                         } else
    4771             :                                 ret = -ESTALE;
    4772           0 :                         goto bad_inode;
    4773             :                 }
    4774             :                 /* The only unlinked inodes we let through here have
    4775             :                  * valid i_mode and are being read by the orphan
    4776             :                  * recovery code: that's fine, we're about to complete
    4777             :                  * the process of deleting those.
    4778             :                  * OR it is the EXT4_BOOT_LOADER_INO which is
    4779             :                  * not initialized on a new filesystem. */
    4780             :         }
    4781           0 :         ei->i_flags = le32_to_cpu(raw_inode->i_flags);
    4782           0 :         ext4_set_inode_flags(inode, true);
    4783           0 :         inode->i_blocks = ext4_inode_blocks(raw_inode, ei);
    4784           0 :         ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo);
    4785           0 :         if (ext4_has_feature_64bit(sb))
    4786           0 :                 ei->i_file_acl |=
    4787           0 :                         ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32;
    4788           0 :         inode->i_size = ext4_isize(sb, raw_inode);
    4789           0 :         if ((size = i_size_read(inode)) < 0) {
    4790           0 :                 ext4_error_inode(inode, function, line, 0,
    4791             :                                  "iget: bad i_size value: %lld", size);
    4792           0 :                 ret = -EFSCORRUPTED;
    4793           0 :                 goto bad_inode;
    4794             :         }
    4795             :         /*
    4796             :          * If dir_index is not enabled but there's dir with INDEX flag set,
    4797             :          * we'd normally treat htree data as empty space. But with metadata
    4798             :          * checksumming that corrupts checksums so forbid that.
    4799             :          */
    4800           0 :         if (!ext4_has_feature_dir_index(sb) && ext4_has_metadata_csum(sb) &&
    4801             :             ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) {
    4802           0 :                 ext4_error_inode(inode, function, line, 0,
    4803             :                          "iget: Dir with htree data on filesystem without dir_index feature.");
    4804           0 :                 ret = -EFSCORRUPTED;
    4805           0 :                 goto bad_inode;
    4806             :         }
    4807           0 :         ei->i_disksize = inode->i_size;
    4808             : #ifdef CONFIG_QUOTA
    4809           0 :         ei->i_reserved_quota = 0;
    4810             : #endif
    4811           0 :         inode->i_generation = le32_to_cpu(raw_inode->i_generation);
    4812           0 :         ei->i_block_group = iloc.block_group;
    4813           0 :         ei->i_last_alloc_group = ~0;
    4814             :         /*
    4815             :          * NOTE! The in-memory inode i_data array is in little-endian order
    4816             :          * even on big-endian machines: we do NOT byteswap the block numbers!
    4817             :          */
    4818           0 :         for (block = 0; block < EXT4_N_BLOCKS; block++)
    4819           0 :                 ei->i_data[block] = raw_inode->i_block[block];
    4820           0 :         INIT_LIST_HEAD(&ei->i_orphan);
    4821           0 :         ext4_fc_init_inode(&ei->vfs_inode);
    4822             : 
    4823             :         /*
    4824             :          * Set transaction id's of transactions that have to be committed
    4825             :          * to finish f[data]sync. We set them to currently running transaction
    4826             :          * as we cannot be sure that the inode or some of its metadata isn't
    4827             :          * part of the transaction - the inode could have been reclaimed and
    4828             :          * now it is reread from disk.
    4829             :          */
    4830           0 :         if (journal) {
    4831           0 :                 transaction_t *transaction;
    4832           0 :                 tid_t tid;
    4833             : 
    4834           0 :                 read_lock(&journal->j_state_lock);
    4835           0 :                 if (journal->j_running_transaction)
    4836             :                         transaction = journal->j_running_transaction;
    4837             :                 else
    4838           0 :                         transaction = journal->j_committing_transaction;
    4839           0 :                 if (transaction)
    4840           0 :                         tid = transaction->t_tid;
    4841             :                 else
    4842           0 :                         tid = journal->j_commit_sequence;
    4843           0 :                 read_unlock(&journal->j_state_lock);
    4844           0 :                 ei->i_sync_tid = tid;
    4845           0 :                 ei->i_datasync_tid = tid;
    4846             :         }
    4847             : 
    4848           0 :         if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
    4849           0 :                 if (ei->i_extra_isize == 0) {
    4850             :                         /* The extra space is currently unused. Use it. */
    4851           0 :                         BUILD_BUG_ON(sizeof(struct ext4_inode) & 3);
    4852           0 :                         ei->i_extra_isize = sizeof(struct ext4_inode) -
    4853             :                                             EXT4_GOOD_OLD_INODE_SIZE;
    4854             :                 } else {
    4855           0 :                         ret = ext4_iget_extra_inode(inode, raw_inode, ei);
    4856           0 :                         if (ret)
    4857           0 :                                 goto bad_inode;
    4858             :                 }
    4859             :         }
    4860             : 
    4861           0 :         EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode);
    4862           0 :         EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode);
    4863           0 :         EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode);
    4864           0 :         EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode);
    4865             : 
    4866           0 :         if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) {
    4867           0 :                 u64 ivers = le32_to_cpu(raw_inode->i_disk_version);
    4868             : 
    4869           0 :                 if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
    4870           0 :                         if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
    4871           0 :                                 ivers |=
    4872           0 :                     (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32;
    4873             :                 }
    4874           0 :                 ext4_inode_set_iversion_queried(inode, ivers);
    4875             :         }
    4876             : 
    4877           0 :         ret = 0;
    4878           0 :         if (ei->i_file_acl &&
    4879           0 :             !ext4_inode_block_valid(inode, ei->i_file_acl, 1)) {
    4880           0 :                 ext4_error_inode(inode, function, line, 0,
    4881             :                                  "iget: bad extended attribute block %llu",
    4882             :                                  ei->i_file_acl);
    4883           0 :                 ret = -EFSCORRUPTED;
    4884           0 :                 goto bad_inode;
    4885           0 :         } else if (!ext4_has_inline_data(inode)) {
    4886             :                 /* validate the block references in the inode */
    4887           0 :                 if (!(EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY) &&
    4888           0 :                         (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
    4889           0 :                         (S_ISLNK(inode->i_mode) &&
    4890           0 :                         !ext4_inode_is_fast_symlink(inode)))) {
    4891           0 :                         if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
    4892           0 :                                 ret = ext4_ext_check_inode(inode);
    4893             :                         else
    4894           0 :                                 ret = ext4_ind_check_inode(inode);
    4895             :                 }
    4896             :         }
    4897           0 :         if (ret)
    4898           0 :                 goto bad_inode;
    4899             : 
    4900           0 :         if (S_ISREG(inode->i_mode)) {
    4901           0 :                 inode->i_op = &ext4_file_inode_operations;
    4902           0 :                 inode->i_fop = &ext4_file_operations;
    4903           0 :                 ext4_set_aops(inode);
    4904           0 :         } else if (S_ISDIR(inode->i_mode)) {
    4905           0 :                 inode->i_op = &ext4_dir_inode_operations;
    4906           0 :                 inode->i_fop = &ext4_dir_operations;
    4907           0 :         } else if (S_ISLNK(inode->i_mode)) {
    4908             :                 /* VFS does not allow setting these so must be corruption */
    4909           0 :                 if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) {
    4910           0 :                         ext4_error_inode(inode, function, line, 0,
    4911             :                                          "iget: immutable or append flags "
    4912             :                                          "not allowed on symlinks");
    4913           0 :                         ret = -EFSCORRUPTED;
    4914           0 :                         goto bad_inode;
    4915             :                 }
    4916           0 :                 if (IS_ENCRYPTED(inode)) {
    4917           0 :                         inode->i_op = &ext4_encrypted_symlink_inode_operations;
    4918           0 :                 } else if (ext4_inode_is_fast_symlink(inode)) {
    4919           0 :                         inode->i_link = (char *)ei->i_data;
    4920           0 :                         inode->i_op = &ext4_fast_symlink_inode_operations;
    4921           0 :                         nd_terminate_link(ei->i_data, inode->i_size,
    4922             :                                 sizeof(ei->i_data) - 1);
    4923             :                 } else {
    4924           0 :                         inode->i_op = &ext4_symlink_inode_operations;
    4925             :                 }
    4926           0 :         } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
    4927           0 :               S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
    4928           0 :                 inode->i_op = &ext4_special_inode_operations;
    4929           0 :                 if (raw_inode->i_block[0])
    4930           0 :                         init_special_inode(inode, inode->i_mode,
    4931             :                            old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
    4932             :                 else
    4933           0 :                         init_special_inode(inode, inode->i_mode,
    4934           0 :                            new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
    4935           0 :         } else if (ino == EXT4_BOOT_LOADER_INO) {
    4936           0 :                 make_bad_inode(inode);
    4937             :         } else {
    4938           0 :                 ret = -EFSCORRUPTED;
    4939           0 :                 ext4_error_inode(inode, function, line, 0,
    4940             :                                  "iget: bogus i_mode (%o)", inode->i_mode);
    4941           0 :                 goto bad_inode;
    4942             :         }
    4943           0 :         if (IS_CASEFOLDED(inode) && !ext4_has_feature_casefold(inode->i_sb))
    4944           0 :                 ext4_error_inode(inode, function, line, 0,
    4945             :                                  "casefold flag without casefold feature");
    4946           0 :         if ((err_str = check_igot_inode(inode, flags)) != NULL) {
    4947           0 :                 ext4_error_inode(inode, function, line, 0, err_str);
    4948           0 :                 ret = -EFSCORRUPTED;
    4949           0 :                 goto bad_inode;
    4950             :         }
    4951             : 
    4952           0 :         brelse(iloc.bh);
    4953           0 :         unlock_new_inode(inode);
    4954           0 :         return inode;
    4955             : 
    4956           0 : bad_inode:
    4957           0 :         brelse(iloc.bh);
    4958           0 :         iget_failed(inode);
    4959           0 :         return ERR_PTR(ret);
    4960             : }
    4961             : 
    4962           0 : static void __ext4_update_other_inode_time(struct super_block *sb,
    4963             :                                            unsigned long orig_ino,
    4964             :                                            unsigned long ino,
    4965             :                                            struct ext4_inode *raw_inode)
    4966             : {
    4967           0 :         struct inode *inode;
    4968             : 
    4969           0 :         inode = find_inode_by_ino_rcu(sb, ino);
    4970           0 :         if (!inode)
    4971             :                 return;
    4972             : 
    4973           0 :         if (!inode_is_dirtytime_only(inode))
    4974             :                 return;
    4975             : 
    4976           0 :         spin_lock(&inode->i_lock);
    4977           0 :         if (inode_is_dirtytime_only(inode)) {
    4978           0 :                 struct ext4_inode_info  *ei = EXT4_I(inode);
    4979             : 
    4980           0 :                 inode->i_state &= ~I_DIRTY_TIME;
    4981           0 :                 spin_unlock(&inode->i_lock);
    4982             : 
    4983           0 :                 spin_lock(&ei->i_raw_lock);
    4984           0 :                 EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode);
    4985           0 :                 EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode);
    4986           0 :                 EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
    4987           0 :                 ext4_inode_csum_set(inode, raw_inode, ei);
    4988           0 :                 spin_unlock(&ei->i_raw_lock);
    4989           0 :                 trace_ext4_other_inode_update_time(inode, orig_ino);
    4990           0 :                 return;
    4991             :         }
    4992           0 :         spin_unlock(&inode->i_lock);
    4993             : }
    4994             : 
    4995             : /*
    4996             :  * Opportunistically update the other time fields for other inodes in
    4997             :  * the same inode table block.
    4998             :  */
    4999           0 : static void ext4_update_other_inodes_time(struct super_block *sb,
    5000             :                                           unsigned long orig_ino, char *buf)
    5001             : {
    5002           0 :         unsigned long ino;
    5003           0 :         int i, inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
    5004           0 :         int inode_size = EXT4_INODE_SIZE(sb);
    5005             : 
    5006             :         /*
    5007             :          * Calculate the first inode in the inode table block.  Inode
    5008             :          * numbers are one-based.  That is, the first inode in a block
    5009             :          * (assuming 4k blocks and 256 byte inodes) is (n*16 + 1).
    5010             :          */
    5011           0 :         ino = ((orig_ino - 1) & ~(inodes_per_block - 1)) + 1;
    5012           0 :         rcu_read_lock();
    5013           0 :         for (i = 0; i < inodes_per_block; i++, ino++, buf += inode_size) {
    5014           0 :                 if (ino == orig_ino)
    5015           0 :                         continue;
    5016           0 :                 __ext4_update_other_inode_time(sb, orig_ino, ino,
    5017             :                                                (struct ext4_inode *)buf);
    5018             :         }
    5019           0 :         rcu_read_unlock();
    5020           0 : }
    5021             : 
    5022             : /*
    5023             :  * Post the struct inode info into an on-disk inode location in the
    5024             :  * buffer-cache.  This gobbles the caller's reference to the
    5025             :  * buffer_head in the inode location struct.
    5026             :  *
    5027             :  * The caller must have write access to iloc->bh.
    5028             :  */
    5029           0 : static int ext4_do_update_inode(handle_t *handle,
    5030             :                                 struct inode *inode,
    5031             :                                 struct ext4_iloc *iloc)
    5032             : {
    5033           0 :         struct ext4_inode *raw_inode = ext4_raw_inode(iloc);
    5034           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    5035           0 :         struct buffer_head *bh = iloc->bh;
    5036           0 :         struct super_block *sb = inode->i_sb;
    5037           0 :         int err;
    5038           0 :         int need_datasync = 0, set_large_file = 0;
    5039             : 
    5040           0 :         spin_lock(&ei->i_raw_lock);
    5041             : 
    5042             :         /*
    5043             :          * For fields not tracked in the in-memory inode, initialise them
    5044             :          * to zero for new inodes.
    5045             :          */
    5046           0 :         if (ext4_test_inode_state(inode, EXT4_STATE_NEW))
    5047           0 :                 memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
    5048             : 
    5049           0 :         if (READ_ONCE(ei->i_disksize) != ext4_isize(inode->i_sb, raw_inode))
    5050           0 :                 need_datasync = 1;
    5051           0 :         if (ei->i_disksize > 0x7fffffffULL) {
    5052           0 :                 if (!ext4_has_feature_large_file(sb) ||
    5053           0 :                     EXT4_SB(sb)->s_es->s_rev_level == cpu_to_le32(EXT4_GOOD_OLD_REV))
    5054             :                         set_large_file = 1;
    5055             :         }
    5056             : 
    5057           0 :         err = ext4_fill_raw_inode(inode, raw_inode);
    5058           0 :         spin_unlock(&ei->i_raw_lock);
    5059           0 :         if (err) {
    5060           0 :                 EXT4_ERROR_INODE(inode, "corrupted inode contents");
    5061           0 :                 goto out_brelse;
    5062             :         }
    5063             : 
    5064           0 :         if (inode->i_sb->s_flags & SB_LAZYTIME)
    5065           0 :                 ext4_update_other_inodes_time(inode->i_sb, inode->i_ino,
    5066             :                                               bh->b_data);
    5067             : 
    5068           0 :         BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
    5069           0 :         err = ext4_handle_dirty_metadata(handle, NULL, bh);
    5070           0 :         if (err)
    5071           0 :                 goto out_error;
    5072           0 :         ext4_clear_inode_state(inode, EXT4_STATE_NEW);
    5073           0 :         if (set_large_file) {
    5074           0 :                 BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get write access");
    5075           0 :                 err = ext4_journal_get_write_access(handle, sb,
    5076             :                                                     EXT4_SB(sb)->s_sbh,
    5077             :                                                     EXT4_JTR_NONE);
    5078           0 :                 if (err)
    5079           0 :                         goto out_error;
    5080           0 :                 lock_buffer(EXT4_SB(sb)->s_sbh);
    5081           0 :                 ext4_set_feature_large_file(sb);
    5082           0 :                 ext4_superblock_csum_set(sb);
    5083           0 :                 unlock_buffer(EXT4_SB(sb)->s_sbh);
    5084           0 :                 ext4_handle_sync(handle);
    5085           0 :                 err = ext4_handle_dirty_metadata(handle, NULL,
    5086             :                                                  EXT4_SB(sb)->s_sbh);
    5087             :         }
    5088           0 :         ext4_update_inode_fsync_trans(handle, inode, need_datasync);
    5089           0 : out_error:
    5090           0 :         ext4_std_error(inode->i_sb, err);
    5091           0 : out_brelse:
    5092           0 :         brelse(bh);
    5093           0 :         return err;
    5094             : }
    5095             : 
    5096             : /*
    5097             :  * ext4_write_inode()
    5098             :  *
    5099             :  * We are called from a few places:
    5100             :  *
    5101             :  * - Within generic_file_aio_write() -> generic_write_sync() for O_SYNC files.
    5102             :  *   Here, there will be no transaction running. We wait for any running
    5103             :  *   transaction to commit.
    5104             :  *
    5105             :  * - Within flush work (sys_sync(), kupdate and such).
    5106             :  *   We wait on commit, if told to.
    5107             :  *
    5108             :  * - Within iput_final() -> write_inode_now()
    5109             :  *   We wait on commit, if told to.
    5110             :  *
    5111             :  * In all cases it is actually safe for us to return without doing anything,
    5112             :  * because the inode has been copied into a raw inode buffer in
    5113             :  * ext4_mark_inode_dirty().  This is a correctness thing for WB_SYNC_ALL
    5114             :  * writeback.
    5115             :  *
    5116             :  * Note that we are absolutely dependent upon all inode dirtiers doing the
    5117             :  * right thing: they *must* call mark_inode_dirty() after dirtying info in
    5118             :  * which we are interested.
    5119             :  *
    5120             :  * It would be a bug for them to not do this.  The code:
    5121             :  *
    5122             :  *      mark_inode_dirty(inode)
    5123             :  *      stuff();
    5124             :  *      inode->i_size = expr;
    5125             :  *
    5126             :  * is in error because write_inode() could occur while `stuff()' is running,
    5127             :  * and the new i_size will be lost.  Plus the inode will no longer be on the
    5128             :  * superblock's dirty inode list.
    5129             :  */
    5130           0 : int ext4_write_inode(struct inode *inode, struct writeback_control *wbc)
    5131             : {
    5132           0 :         int err;
    5133             : 
    5134           0 :         if (WARN_ON_ONCE(current->flags & PF_MEMALLOC) ||
    5135           0 :             sb_rdonly(inode->i_sb))
    5136             :                 return 0;
    5137             : 
    5138           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
    5139             :                 return -EIO;
    5140             : 
    5141           0 :         if (EXT4_SB(inode->i_sb)->s_journal) {
    5142           0 :                 if (ext4_journal_current_handle()) {
    5143           0 :                         ext4_debug("called recursively, non-PF_MEMALLOC!\n");
    5144           0 :                         dump_stack();
    5145           0 :                         return -EIO;
    5146             :                 }
    5147             : 
    5148             :                 /*
    5149             :                  * No need to force transaction in WB_SYNC_NONE mode. Also
    5150             :                  * ext4_sync_fs() will force the commit after everything is
    5151             :                  * written.
    5152             :                  */
    5153           0 :                 if (wbc->sync_mode != WB_SYNC_ALL || wbc->for_sync)
    5154             :                         return 0;
    5155             : 
    5156           0 :                 err = ext4_fc_commit(EXT4_SB(inode->i_sb)->s_journal,
    5157           0 :                                                 EXT4_I(inode)->i_sync_tid);
    5158             :         } else {
    5159           0 :                 struct ext4_iloc iloc;
    5160             : 
    5161           0 :                 err = __ext4_get_inode_loc_noinmem(inode, &iloc);
    5162           0 :                 if (err)
    5163           0 :                         return err;
    5164             :                 /*
    5165             :                  * sync(2) will flush the whole buffer cache. No need to do
    5166             :                  * it here separately for each inode.
    5167             :                  */
    5168           0 :                 if (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync)
    5169           0 :                         sync_dirty_buffer(iloc.bh);
    5170           0 :                 if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) {
    5171           0 :                         ext4_error_inode_block(inode, iloc.bh->b_blocknr, EIO,
    5172             :                                                "IO error syncing inode");
    5173           0 :                         err = -EIO;
    5174             :                 }
    5175           0 :                 brelse(iloc.bh);
    5176             :         }
    5177             :         return err;
    5178             : }
    5179             : 
    5180             : /*
    5181             :  * In data=journal mode ext4_journalled_invalidate_folio() may fail to invalidate
    5182             :  * buffers that are attached to a folio straddling i_size and are undergoing
    5183             :  * commit. In that case we have to wait for commit to finish and try again.
    5184             :  */
    5185           0 : static void ext4_wait_for_tail_page_commit(struct inode *inode)
    5186             : {
    5187           0 :         unsigned offset;
    5188           0 :         journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
    5189           0 :         tid_t commit_tid = 0;
    5190           0 :         int ret;
    5191             : 
    5192           0 :         offset = inode->i_size & (PAGE_SIZE - 1);
    5193             :         /*
    5194             :          * If the folio is fully truncated, we don't need to wait for any commit
    5195             :          * (and we even should not as __ext4_journalled_invalidate_folio() may
    5196             :          * strip all buffers from the folio but keep the folio dirty which can then
    5197             :          * confuse e.g. concurrent ext4_writepages() seeing dirty folio without
    5198             :          * buffers). Also we don't need to wait for any commit if all buffers in
    5199             :          * the folio remain valid. This is most beneficial for the common case of
    5200             :          * blocksize == PAGESIZE.
    5201             :          */
    5202           0 :         if (!offset || offset > (PAGE_SIZE - i_blocksize(inode)))
    5203             :                 return;
    5204           0 :         while (1) {
    5205           0 :                 struct folio *folio = filemap_lock_folio(inode->i_mapping,
    5206           0 :                                       inode->i_size >> PAGE_SHIFT);
    5207           0 :                 if (IS_ERR(folio))
    5208             :                         return;
    5209           0 :                 ret = __ext4_journalled_invalidate_folio(folio, offset,
    5210             :                                                 folio_size(folio) - offset);
    5211           0 :                 folio_unlock(folio);
    5212           0 :                 folio_put(folio);
    5213           0 :                 if (ret != -EBUSY)
    5214             :                         return;
    5215           0 :                 commit_tid = 0;
    5216           0 :                 read_lock(&journal->j_state_lock);
    5217           0 :                 if (journal->j_committing_transaction)
    5218           0 :                         commit_tid = journal->j_committing_transaction->t_tid;
    5219           0 :                 read_unlock(&journal->j_state_lock);
    5220           0 :                 if (commit_tid)
    5221           0 :                         jbd2_log_wait_commit(journal, commit_tid);
    5222             :         }
    5223             : }
    5224             : 
    5225             : /*
    5226             :  * ext4_setattr()
    5227             :  *
    5228             :  * Called from notify_change.
    5229             :  *
    5230             :  * We want to trap VFS attempts to truncate the file as soon as
    5231             :  * possible.  In particular, we want to make sure that when the VFS
    5232             :  * shrinks i_size, we put the inode on the orphan list and modify
    5233             :  * i_disksize immediately, so that during the subsequent flushing of
    5234             :  * dirty pages and freeing of disk blocks, we can guarantee that any
    5235             :  * commit will leave the blocks being flushed in an unused state on
    5236             :  * disk.  (On recovery, the inode will get truncated and the blocks will
    5237             :  * be freed, so we have a strong guarantee that no future commit will
    5238             :  * leave these blocks visible to the user.)
    5239             :  *
    5240             :  * Another thing we have to assure is that if we are in ordered mode
    5241             :  * and inode is still attached to the committing transaction, we must
    5242             :  * we start writeout of all the dirty pages which are being truncated.
    5243             :  * This way we are sure that all the data written in the previous
    5244             :  * transaction are already on disk (truncate waits for pages under
    5245             :  * writeback).
    5246             :  *
    5247             :  * Called with inode->i_rwsem down.
    5248             :  */
    5249           0 : int ext4_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
    5250             :                  struct iattr *attr)
    5251             : {
    5252           0 :         struct inode *inode = d_inode(dentry);
    5253           0 :         int error, rc = 0;
    5254           0 :         int orphan = 0;
    5255           0 :         const unsigned int ia_valid = attr->ia_valid;
    5256           0 :         bool inc_ivers = true;
    5257             : 
    5258           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
    5259             :                 return -EIO;
    5260             : 
    5261           0 :         if (unlikely(IS_IMMUTABLE(inode)))
    5262             :                 return -EPERM;
    5263             : 
    5264           0 :         if (unlikely(IS_APPEND(inode) &&
    5265             :                      (ia_valid & (ATTR_MODE | ATTR_UID |
    5266             :                                   ATTR_GID | ATTR_TIMES_SET))))
    5267             :                 return -EPERM;
    5268             : 
    5269           0 :         error = setattr_prepare(idmap, dentry, attr);
    5270           0 :         if (error)
    5271             :                 return error;
    5272             : 
    5273           0 :         error = fscrypt_prepare_setattr(dentry, attr);
    5274           0 :         if (error)
    5275             :                 return error;
    5276             : 
    5277           0 :         error = fsverity_prepare_setattr(dentry, attr);
    5278           0 :         if (error)
    5279             :                 return error;
    5280             : 
    5281           0 :         if (is_quota_modification(idmap, inode, attr)) {
    5282           0 :                 error = dquot_initialize(inode);
    5283           0 :                 if (error)
    5284             :                         return error;
    5285             :         }
    5286             : 
    5287           0 :         if (i_uid_needs_update(idmap, attr, inode) ||
    5288           0 :             i_gid_needs_update(idmap, attr, inode)) {
    5289           0 :                 handle_t *handle;
    5290             : 
    5291             :                 /* (user+group)*(old+new) structure, inode write (sb,
    5292             :                  * inode block, ? - but truncate inode update has it) */
    5293           0 :                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
    5294             :                         (EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb) +
    5295             :                          EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)) + 3);
    5296           0 :                 if (IS_ERR(handle)) {
    5297           0 :                         error = PTR_ERR(handle);
    5298           0 :                         goto err_out;
    5299             :                 }
    5300             : 
    5301             :                 /* dquot_transfer() calls back ext4_get_inode_usage() which
    5302             :                  * counts xattr inode references.
    5303             :                  */
    5304           0 :                 down_read(&EXT4_I(inode)->xattr_sem);
    5305           0 :                 error = dquot_transfer(idmap, inode, attr);
    5306           0 :                 up_read(&EXT4_I(inode)->xattr_sem);
    5307             : 
    5308           0 :                 if (error) {
    5309           0 :                         ext4_journal_stop(handle);
    5310           0 :                         return error;
    5311             :                 }
    5312             :                 /* Update corresponding info in inode so that everything is in
    5313             :                  * one transaction */
    5314           0 :                 i_uid_update(idmap, attr, inode);
    5315           0 :                 i_gid_update(idmap, attr, inode);
    5316           0 :                 error = ext4_mark_inode_dirty(handle, inode);
    5317           0 :                 ext4_journal_stop(handle);
    5318           0 :                 if (unlikely(error)) {
    5319             :                         return error;
    5320             :                 }
    5321             :         }
    5322             : 
    5323           0 :         if (attr->ia_valid & ATTR_SIZE) {
    5324           0 :                 handle_t *handle;
    5325           0 :                 loff_t oldsize = inode->i_size;
    5326           0 :                 loff_t old_disksize;
    5327           0 :                 int shrink = (attr->ia_size < inode->i_size);
    5328             : 
    5329           0 :                 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
    5330           0 :                         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    5331             : 
    5332           0 :                         if (attr->ia_size > sbi->s_bitmap_maxbytes) {
    5333             :                                 return -EFBIG;
    5334             :                         }
    5335             :                 }
    5336           0 :                 if (!S_ISREG(inode->i_mode)) {
    5337             :                         return -EINVAL;
    5338             :                 }
    5339             : 
    5340           0 :                 if (attr->ia_size == inode->i_size)
    5341           0 :                         inc_ivers = false;
    5342             : 
    5343           0 :                 if (shrink) {
    5344           0 :                         if (ext4_should_order_data(inode)) {
    5345           0 :                                 error = ext4_begin_ordered_truncate(inode,
    5346             :                                                             attr->ia_size);
    5347           0 :                                 if (error)
    5348           0 :                                         goto err_out;
    5349             :                         }
    5350             :                         /*
    5351             :                          * Blocks are going to be removed from the inode. Wait
    5352             :                          * for dio in flight.
    5353             :                          */
    5354           0 :                         inode_dio_wait(inode);
    5355             :                 }
    5356             : 
    5357           0 :                 filemap_invalidate_lock(inode->i_mapping);
    5358             : 
    5359           0 :                 rc = ext4_break_layouts(inode);
    5360           0 :                 if (rc) {
    5361           0 :                         filemap_invalidate_unlock(inode->i_mapping);
    5362           0 :                         goto err_out;
    5363             :                 }
    5364             : 
    5365           0 :                 if (attr->ia_size != inode->i_size) {
    5366           0 :                         handle = ext4_journal_start(inode, EXT4_HT_INODE, 3);
    5367           0 :                         if (IS_ERR(handle)) {
    5368           0 :                                 error = PTR_ERR(handle);
    5369           0 :                                 goto out_mmap_sem;
    5370             :                         }
    5371           0 :                         if (ext4_handle_valid(handle) && shrink) {
    5372           0 :                                 error = ext4_orphan_add(handle, inode);
    5373           0 :                                 orphan = 1;
    5374             :                         }
    5375             :                         /*
    5376             :                          * Update c/mtime on truncate up, ext4_truncate() will
    5377             :                          * update c/mtime in shrink case below
    5378             :                          */
    5379           0 :                         if (!shrink) {
    5380           0 :                                 inode->i_mtime = current_time(inode);
    5381           0 :                                 inode->i_ctime = inode->i_mtime;
    5382             :                         }
    5383             : 
    5384           0 :                         if (shrink)
    5385           0 :                                 ext4_fc_track_range(handle, inode,
    5386           0 :                                         (attr->ia_size > 0 ? attr->ia_size - 1 : 0) >>
    5387           0 :                                         inode->i_sb->s_blocksize_bits,
    5388             :                                         EXT_MAX_BLOCKS - 1);
    5389             :                         else
    5390           0 :                                 ext4_fc_track_range(
    5391             :                                         handle, inode,
    5392           0 :                                         (oldsize > 0 ? oldsize - 1 : oldsize) >>
    5393           0 :                                         inode->i_sb->s_blocksize_bits,
    5394           0 :                                         (attr->ia_size > 0 ? attr->ia_size - 1 : 0) >>
    5395             :                                         inode->i_sb->s_blocksize_bits);
    5396             : 
    5397           0 :                         down_write(&EXT4_I(inode)->i_data_sem);
    5398           0 :                         old_disksize = EXT4_I(inode)->i_disksize;
    5399           0 :                         EXT4_I(inode)->i_disksize = attr->ia_size;
    5400           0 :                         rc = ext4_mark_inode_dirty(handle, inode);
    5401           0 :                         if (!error)
    5402           0 :                                 error = rc;
    5403             :                         /*
    5404             :                          * We have to update i_size under i_data_sem together
    5405             :                          * with i_disksize to avoid races with writeback code
    5406             :                          * running ext4_wb_update_i_disksize().
    5407             :                          */
    5408           0 :                         if (!error)
    5409           0 :                                 i_size_write(inode, attr->ia_size);
    5410             :                         else
    5411           0 :                                 EXT4_I(inode)->i_disksize = old_disksize;
    5412           0 :                         up_write(&EXT4_I(inode)->i_data_sem);
    5413           0 :                         ext4_journal_stop(handle);
    5414           0 :                         if (error)
    5415           0 :                                 goto out_mmap_sem;
    5416           0 :                         if (!shrink) {
    5417           0 :                                 pagecache_isize_extended(inode, oldsize,
    5418             :                                                          inode->i_size);
    5419           0 :                         } else if (ext4_should_journal_data(inode)) {
    5420           0 :                                 ext4_wait_for_tail_page_commit(inode);
    5421             :                         }
    5422             :                 }
    5423             : 
    5424             :                 /*
    5425             :                  * Truncate pagecache after we've waited for commit
    5426             :                  * in data=journal mode to make pages freeable.
    5427             :                  */
    5428           0 :                 truncate_pagecache(inode, inode->i_size);
    5429             :                 /*
    5430             :                  * Call ext4_truncate() even if i_size didn't change to
    5431             :                  * truncate possible preallocated blocks.
    5432             :                  */
    5433           0 :                 if (attr->ia_size <= oldsize) {
    5434           0 :                         rc = ext4_truncate(inode);
    5435           0 :                         if (rc)
    5436           0 :                                 error = rc;
    5437             :                 }
    5438           0 : out_mmap_sem:
    5439           0 :                 filemap_invalidate_unlock(inode->i_mapping);
    5440             :         }
    5441             : 
    5442           0 :         if (!error) {
    5443           0 :                 if (inc_ivers)
    5444           0 :                         inode_inc_iversion(inode);
    5445           0 :                 setattr_copy(idmap, inode, attr);
    5446           0 :                 mark_inode_dirty(inode);
    5447             :         }
    5448             : 
    5449             :         /*
    5450             :          * If the call to ext4_truncate failed to get a transaction handle at
    5451             :          * all, we need to clean up the in-core orphan list manually.
    5452             :          */
    5453           0 :         if (orphan && inode->i_nlink)
    5454           0 :                 ext4_orphan_del(NULL, inode);
    5455             : 
    5456           0 :         if (!error && (ia_valid & ATTR_MODE))
    5457           0 :                 rc = posix_acl_chmod(idmap, dentry, inode->i_mode);
    5458             : 
    5459           0 : err_out:
    5460           0 :         if  (error)
    5461           0 :                 ext4_std_error(inode->i_sb, error);
    5462           0 :         if (!error)
    5463           0 :                 error = rc;
    5464             :         return error;
    5465             : }
    5466             : 
    5467           0 : u32 ext4_dio_alignment(struct inode *inode)
    5468             : {
    5469           0 :         if (fsverity_active(inode))
    5470             :                 return 0;
    5471           0 :         if (ext4_should_journal_data(inode))
    5472             :                 return 0;
    5473           0 :         if (ext4_has_inline_data(inode))
    5474             :                 return 0;
    5475           0 :         if (IS_ENCRYPTED(inode)) {
    5476           0 :                 if (!fscrypt_dio_supported(inode))
    5477             :                         return 0;
    5478           0 :                 return i_blocksize(inode);
    5479             :         }
    5480             :         return 1; /* use the iomap defaults */
    5481             : }
    5482             : 
    5483           0 : int ext4_getattr(struct mnt_idmap *idmap, const struct path *path,
    5484             :                  struct kstat *stat, u32 request_mask, unsigned int query_flags)
    5485             : {
    5486           0 :         struct inode *inode = d_inode(path->dentry);
    5487           0 :         struct ext4_inode *raw_inode;
    5488           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    5489           0 :         unsigned int flags;
    5490             : 
    5491           0 :         if ((request_mask & STATX_BTIME) &&
    5492           0 :             EXT4_FITS_IN_INODE(raw_inode, ei, i_crtime)) {
    5493           0 :                 stat->result_mask |= STATX_BTIME;
    5494           0 :                 stat->btime.tv_sec = ei->i_crtime.tv_sec;
    5495           0 :                 stat->btime.tv_nsec = ei->i_crtime.tv_nsec;
    5496             :         }
    5497             : 
    5498             :         /*
    5499             :          * Return the DIO alignment restrictions if requested.  We only return
    5500             :          * this information when requested, since on encrypted files it might
    5501             :          * take a fair bit of work to get if the file wasn't opened recently.
    5502             :          */
    5503           0 :         if ((request_mask & STATX_DIOALIGN) && S_ISREG(inode->i_mode)) {
    5504           0 :                 u32 dio_align = ext4_dio_alignment(inode);
    5505             : 
    5506           0 :                 stat->result_mask |= STATX_DIOALIGN;
    5507           0 :                 if (dio_align == 1) {
    5508           0 :                         struct block_device *bdev = inode->i_sb->s_bdev;
    5509             : 
    5510             :                         /* iomap defaults */
    5511           0 :                         stat->dio_mem_align = bdev_dma_alignment(bdev) + 1;
    5512           0 :                         stat->dio_offset_align = bdev_logical_block_size(bdev);
    5513             :                 } else {
    5514           0 :                         stat->dio_mem_align = dio_align;
    5515           0 :                         stat->dio_offset_align = dio_align;
    5516             :                 }
    5517             :         }
    5518             : 
    5519           0 :         flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
    5520           0 :         if (flags & EXT4_APPEND_FL)
    5521           0 :                 stat->attributes |= STATX_ATTR_APPEND;
    5522           0 :         if (flags & EXT4_COMPR_FL)
    5523           0 :                 stat->attributes |= STATX_ATTR_COMPRESSED;
    5524           0 :         if (flags & EXT4_ENCRYPT_FL)
    5525           0 :                 stat->attributes |= STATX_ATTR_ENCRYPTED;
    5526           0 :         if (flags & EXT4_IMMUTABLE_FL)
    5527           0 :                 stat->attributes |= STATX_ATTR_IMMUTABLE;
    5528           0 :         if (flags & EXT4_NODUMP_FL)
    5529           0 :                 stat->attributes |= STATX_ATTR_NODUMP;
    5530           0 :         if (flags & EXT4_VERITY_FL)
    5531           0 :                 stat->attributes |= STATX_ATTR_VERITY;
    5532             : 
    5533           0 :         stat->attributes_mask |= (STATX_ATTR_APPEND |
    5534             :                                   STATX_ATTR_COMPRESSED |
    5535             :                                   STATX_ATTR_ENCRYPTED |
    5536             :                                   STATX_ATTR_IMMUTABLE |
    5537             :                                   STATX_ATTR_NODUMP |
    5538             :                                   STATX_ATTR_VERITY);
    5539             : 
    5540           0 :         generic_fillattr(idmap, inode, stat);
    5541           0 :         return 0;
    5542             : }
    5543             : 
    5544           0 : int ext4_file_getattr(struct mnt_idmap *idmap,
    5545             :                       const struct path *path, struct kstat *stat,
    5546             :                       u32 request_mask, unsigned int query_flags)
    5547             : {
    5548           0 :         struct inode *inode = d_inode(path->dentry);
    5549           0 :         u64 delalloc_blocks;
    5550             : 
    5551           0 :         ext4_getattr(idmap, path, stat, request_mask, query_flags);
    5552             : 
    5553             :         /*
    5554             :          * If there is inline data in the inode, the inode will normally not
    5555             :          * have data blocks allocated (it may have an external xattr block).
    5556             :          * Report at least one sector for such files, so tools like tar, rsync,
    5557             :          * others don't incorrectly think the file is completely sparse.
    5558             :          */
    5559           0 :         if (unlikely(ext4_has_inline_data(inode)))
    5560           0 :                 stat->blocks += (stat->size + 511) >> 9;
    5561             : 
    5562             :         /*
    5563             :          * We can't update i_blocks if the block allocation is delayed
    5564             :          * otherwise in the case of system crash before the real block
    5565             :          * allocation is done, we will have i_blocks inconsistent with
    5566             :          * on-disk file blocks.
    5567             :          * We always keep i_blocks updated together with real
    5568             :          * allocation. But to not confuse with user, stat
    5569             :          * will return the blocks that include the delayed allocation
    5570             :          * blocks for this file.
    5571             :          */
    5572           0 :         delalloc_blocks = EXT4_C2B(EXT4_SB(inode->i_sb),
    5573             :                                    EXT4_I(inode)->i_reserved_data_blocks);
    5574           0 :         stat->blocks += delalloc_blocks << (inode->i_sb->s_blocksize_bits - 9);
    5575           0 :         return 0;
    5576             : }
    5577             : 
    5578           0 : static int ext4_index_trans_blocks(struct inode *inode, int lblocks,
    5579             :                                    int pextents)
    5580             : {
    5581           0 :         if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
    5582           0 :                 return ext4_ind_trans_blocks(inode, lblocks);
    5583           0 :         return ext4_ext_index_trans_blocks(inode, pextents);
    5584             : }
    5585             : 
    5586             : /*
    5587             :  * Account for index blocks, block groups bitmaps and block group
    5588             :  * descriptor blocks if modify datablocks and index blocks
    5589             :  * worse case, the indexs blocks spread over different block groups
    5590             :  *
    5591             :  * If datablocks are discontiguous, they are possible to spread over
    5592             :  * different block groups too. If they are contiguous, with flexbg,
    5593             :  * they could still across block group boundary.
    5594             :  *
    5595             :  * Also account for superblock, inode, quota and xattr blocks
    5596             :  */
    5597           0 : static int ext4_meta_trans_blocks(struct inode *inode, int lblocks,
    5598             :                                   int pextents)
    5599             : {
    5600           0 :         ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb);
    5601           0 :         int gdpblocks;
    5602           0 :         int idxblocks;
    5603           0 :         int ret;
    5604             : 
    5605             :         /*
    5606             :          * How many index blocks need to touch to map @lblocks logical blocks
    5607             :          * to @pextents physical extents?
    5608             :          */
    5609           0 :         idxblocks = ext4_index_trans_blocks(inode, lblocks, pextents);
    5610             : 
    5611           0 :         ret = idxblocks;
    5612             : 
    5613             :         /*
    5614             :          * Now let's see how many group bitmaps and group descriptors need
    5615             :          * to account
    5616             :          */
    5617           0 :         groups = idxblocks + pextents;
    5618           0 :         gdpblocks = groups;
    5619           0 :         if (groups > ngroups)
    5620             :                 groups = ngroups;
    5621           0 :         if (groups > EXT4_SB(inode->i_sb)->s_gdb_count)
    5622           0 :                 gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count;
    5623             : 
    5624             :         /* bitmaps and block group descriptor blocks */
    5625           0 :         ret += groups + gdpblocks;
    5626             : 
    5627             :         /* Blocks for super block, inode, quota and xattr blocks */
    5628           0 :         ret += EXT4_META_TRANS_BLOCKS(inode->i_sb);
    5629             : 
    5630           0 :         return ret;
    5631             : }
    5632             : 
    5633             : /*
    5634             :  * Calculate the total number of credits to reserve to fit
    5635             :  * the modification of a single pages into a single transaction,
    5636             :  * which may include multiple chunks of block allocations.
    5637             :  *
    5638             :  * This could be called via ext4_write_begin()
    5639             :  *
    5640             :  * We need to consider the worse case, when
    5641             :  * one new block per extent.
    5642             :  */
    5643           0 : int ext4_writepage_trans_blocks(struct inode *inode)
    5644             : {
    5645           0 :         int bpp = ext4_journal_blocks_per_page(inode);
    5646           0 :         int ret;
    5647             : 
    5648           0 :         ret = ext4_meta_trans_blocks(inode, bpp, bpp);
    5649             : 
    5650             :         /* Account for data blocks for journalled mode */
    5651           0 :         if (ext4_should_journal_data(inode))
    5652           0 :                 ret += bpp;
    5653           0 :         return ret;
    5654             : }
    5655             : 
    5656             : /*
    5657             :  * Calculate the journal credits for a chunk of data modification.
    5658             :  *
    5659             :  * This is called from DIO, fallocate or whoever calling
    5660             :  * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
    5661             :  *
    5662             :  * journal buffers for data blocks are not included here, as DIO
    5663             :  * and fallocate do no need to journal data buffers.
    5664             :  */
    5665           0 : int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks)
    5666             : {
    5667           0 :         return ext4_meta_trans_blocks(inode, nrblocks, 1);
    5668             : }
    5669             : 
    5670             : /*
    5671             :  * The caller must have previously called ext4_reserve_inode_write().
    5672             :  * Give this, we know that the caller already has write access to iloc->bh.
    5673             :  */
    5674           0 : int ext4_mark_iloc_dirty(handle_t *handle,
    5675             :                          struct inode *inode, struct ext4_iloc *iloc)
    5676             : {
    5677           0 :         int err = 0;
    5678             : 
    5679           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) {
    5680           0 :                 put_bh(iloc->bh);
    5681           0 :                 return -EIO;
    5682             :         }
    5683           0 :         ext4_fc_track_inode(handle, inode);
    5684             : 
    5685             :         /* the do_update_inode consumes one bh->b_count */
    5686           0 :         get_bh(iloc->bh);
    5687             : 
    5688             :         /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
    5689           0 :         err = ext4_do_update_inode(handle, inode, iloc);
    5690           0 :         put_bh(iloc->bh);
    5691           0 :         return err;
    5692             : }
    5693             : 
    5694             : /*
    5695             :  * On success, We end up with an outstanding reference count against
    5696             :  * iloc->bh.  This _must_ be cleaned up later.
    5697             :  */
    5698             : 
    5699             : int
    5700           0 : ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
    5701             :                          struct ext4_iloc *iloc)
    5702             : {
    5703           0 :         int err;
    5704             : 
    5705           0 :         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
    5706             :                 return -EIO;
    5707             : 
    5708           0 :         err = ext4_get_inode_loc(inode, iloc);
    5709           0 :         if (!err) {
    5710           0 :                 BUFFER_TRACE(iloc->bh, "get_write_access");
    5711           0 :                 err = ext4_journal_get_write_access(handle, inode->i_sb,
    5712             :                                                     iloc->bh, EXT4_JTR_NONE);
    5713           0 :                 if (err) {
    5714           0 :                         brelse(iloc->bh);
    5715           0 :                         iloc->bh = NULL;
    5716             :                 }
    5717             :         }
    5718           0 :         ext4_std_error(inode->i_sb, err);
    5719             :         return err;
    5720             : }
    5721             : 
    5722           0 : static int __ext4_expand_extra_isize(struct inode *inode,
    5723             :                                      unsigned int new_extra_isize,
    5724             :                                      struct ext4_iloc *iloc,
    5725             :                                      handle_t *handle, int *no_expand)
    5726             : {
    5727           0 :         struct ext4_inode *raw_inode;
    5728           0 :         struct ext4_xattr_ibody_header *header;
    5729           0 :         unsigned int inode_size = EXT4_INODE_SIZE(inode->i_sb);
    5730           0 :         struct ext4_inode_info *ei = EXT4_I(inode);
    5731           0 :         int error;
    5732             : 
    5733             :         /* this was checked at iget time, but double check for good measure */
    5734           0 :         if ((EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > inode_size) ||
    5735             :             (ei->i_extra_isize & 3)) {
    5736           0 :                 EXT4_ERROR_INODE(inode, "bad extra_isize %u (inode size %u)",
    5737             :                                  ei->i_extra_isize,
    5738             :                                  EXT4_INODE_SIZE(inode->i_sb));
    5739           0 :                 return -EFSCORRUPTED;
    5740             :         }
    5741           0 :         if ((new_extra_isize < ei->i_extra_isize) ||
    5742           0 :             (new_extra_isize < 4) ||
    5743           0 :             (new_extra_isize > inode_size - EXT4_GOOD_OLD_INODE_SIZE))
    5744             :                 return -EINVAL; /* Should never happen */
    5745             : 
    5746           0 :         raw_inode = ext4_raw_inode(iloc);
    5747             : 
    5748           0 :         header = IHDR(inode, raw_inode);
    5749             : 
    5750             :         /* No extended attributes present */
    5751           0 :         if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR) ||
    5752           0 :             header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) {
    5753           0 :                 memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE +
    5754             :                        EXT4_I(inode)->i_extra_isize, 0,
    5755             :                        new_extra_isize - EXT4_I(inode)->i_extra_isize);
    5756           0 :                 EXT4_I(inode)->i_extra_isize = new_extra_isize;
    5757           0 :                 return 0;
    5758             :         }
    5759             : 
    5760             :         /*
    5761             :          * We may need to allocate external xattr block so we need quotas
    5762             :          * initialized. Here we can be called with various locks held so we
    5763             :          * cannot affort to initialize quotas ourselves. So just bail.
    5764             :          */
    5765           0 :         if (dquot_initialize_needed(inode))
    5766             :                 return -EAGAIN;
    5767             : 
    5768             :         /* try to expand with EAs present */
    5769           0 :         error = ext4_expand_extra_isize_ea(inode, new_extra_isize,
    5770             :                                            raw_inode, handle);
    5771           0 :         if (error) {
    5772             :                 /*
    5773             :                  * Inode size expansion failed; don't try again
    5774             :                  */
    5775           0 :                 *no_expand = 1;
    5776             :         }
    5777             : 
    5778             :         return error;
    5779             : }
    5780             : 
    5781             : /*
    5782             :  * Expand an inode by new_extra_isize bytes.
    5783             :  * Returns 0 on success or negative error number on failure.
    5784             :  */
    5785           0 : static int ext4_try_to_expand_extra_isize(struct inode *inode,
    5786             :                                           unsigned int new_extra_isize,
    5787             :                                           struct ext4_iloc iloc,
    5788             :                                           handle_t *handle)
    5789             : {
    5790           0 :         int no_expand;
    5791           0 :         int error;
    5792             : 
    5793           0 :         if (ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND))
    5794             :                 return -EOVERFLOW;
    5795             : 
    5796             :         /*
    5797             :          * In nojournal mode, we can immediately attempt to expand
    5798             :          * the inode.  When journaled, we first need to obtain extra
    5799             :          * buffer credits since we may write into the EA block
    5800             :          * with this same handle. If journal_extend fails, then it will
    5801             :          * only result in a minor loss of functionality for that inode.
    5802             :          * If this is felt to be critical, then e2fsck should be run to
    5803             :          * force a large enough s_min_extra_isize.
    5804             :          */
    5805           0 :         if (ext4_journal_extend(handle,
    5806           0 :                                 EXT4_DATA_TRANS_BLOCKS(inode->i_sb), 0) != 0)
    5807             :                 return -ENOSPC;
    5808             : 
    5809           0 :         if (ext4_write_trylock_xattr(inode, &no_expand) == 0)
    5810             :                 return -EBUSY;
    5811             : 
    5812           0 :         error = __ext4_expand_extra_isize(inode, new_extra_isize, &iloc,
    5813             :                                           handle, &no_expand);
    5814           0 :         ext4_write_unlock_xattr(inode, &no_expand);
    5815             : 
    5816           0 :         return error;
    5817             : }
    5818             : 
    5819           0 : int ext4_expand_extra_isize(struct inode *inode,
    5820             :                             unsigned int new_extra_isize,
    5821             :                             struct ext4_iloc *iloc)
    5822             : {
    5823           0 :         handle_t *handle;
    5824           0 :         int no_expand;
    5825           0 :         int error, rc;
    5826             : 
    5827           0 :         if (ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) {
    5828           0 :                 brelse(iloc->bh);
    5829           0 :                 return -EOVERFLOW;
    5830             :         }
    5831             : 
    5832           0 :         handle = ext4_journal_start(inode, EXT4_HT_INODE,
    5833             :                                     EXT4_DATA_TRANS_BLOCKS(inode->i_sb));
    5834           0 :         if (IS_ERR(handle)) {
    5835           0 :                 error = PTR_ERR(handle);
    5836           0 :                 brelse(iloc->bh);
    5837           0 :                 return error;
    5838             :         }
    5839             : 
    5840           0 :         ext4_write_lock_xattr(inode, &no_expand);
    5841             : 
    5842           0 :         BUFFER_TRACE(iloc->bh, "get_write_access");
    5843           0 :         error = ext4_journal_get_write_access(handle, inode->i_sb, iloc->bh,
    5844             :                                               EXT4_JTR_NONE);
    5845           0 :         if (error) {
    5846           0 :                 brelse(iloc->bh);
    5847           0 :                 goto out_unlock;
    5848             :         }
    5849             : 
    5850           0 :         error = __ext4_expand_extra_isize(inode, new_extra_isize, iloc,
    5851             :                                           handle, &no_expand);
    5852             : 
    5853           0 :         rc = ext4_mark_iloc_dirty(handle, inode, iloc);
    5854           0 :         if (!error)
    5855           0 :                 error = rc;
    5856             : 
    5857           0 : out_unlock:
    5858           0 :         ext4_write_unlock_xattr(inode, &no_expand);
    5859           0 :         ext4_journal_stop(handle);
    5860           0 :         return error;
    5861             : }
    5862             : 
    5863             : /*
    5864             :  * What we do here is to mark the in-core inode as clean with respect to inode
    5865             :  * dirtiness (it may still be data-dirty).
    5866             :  * This means that the in-core inode may be reaped by prune_icache
    5867             :  * without having to perform any I/O.  This is a very good thing,
    5868             :  * because *any* task may call prune_icache - even ones which
    5869             :  * have a transaction open against a different journal.
    5870             :  *
    5871             :  * Is this cheating?  Not really.  Sure, we haven't written the
    5872             :  * inode out, but prune_icache isn't a user-visible syncing function.
    5873             :  * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
    5874             :  * we start and wait on commits.
    5875             :  */
    5876           0 : int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
    5877             :                                 const char *func, unsigned int line)
    5878             : {
    5879           0 :         struct ext4_iloc iloc;
    5880           0 :         struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
    5881           0 :         int err;
    5882             : 
    5883           0 :         might_sleep();
    5884           0 :         trace_ext4_mark_inode_dirty(inode, _RET_IP_);
    5885           0 :         err = ext4_reserve_inode_write(handle, inode, &iloc);
    5886           0 :         if (err)
    5887           0 :                 goto out;
    5888             : 
    5889           0 :         if (EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize)
    5890           0 :                 ext4_try_to_expand_extra_isize(inode, sbi->s_want_extra_isize,
    5891             :                                                iloc, handle);
    5892             : 
    5893           0 :         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
    5894           0 : out:
    5895           0 :         if (unlikely(err))
    5896           0 :                 ext4_error_inode_err(inode, func, line, 0, err,
    5897             :                                         "mark_inode_dirty error");
    5898           0 :         return err;
    5899             : }
    5900             : 
    5901             : /*
    5902             :  * ext4_dirty_inode() is called from __mark_inode_dirty()
    5903             :  *
    5904             :  * We're really interested in the case where a file is being extended.
    5905             :  * i_size has been changed by generic_commit_write() and we thus need
    5906             :  * to include the updated inode in the current transaction.
    5907             :  *
    5908             :  * Also, dquot_alloc_block() will always dirty the inode when blocks
    5909             :  * are allocated to the file.
    5910             :  *
    5911             :  * If the inode is marked synchronous, we don't honour that here - doing
    5912             :  * so would cause a commit on atime updates, which we don't bother doing.
    5913             :  * We handle synchronous inodes at the highest possible level.
    5914             :  */
    5915           0 : void ext4_dirty_inode(struct inode *inode, int flags)
    5916             : {
    5917           0 :         handle_t *handle;
    5918             : 
    5919           0 :         handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
    5920           0 :         if (IS_ERR(handle))
    5921             :                 return;
    5922           0 :         ext4_mark_inode_dirty(handle, inode);
    5923           0 :         ext4_journal_stop(handle);
    5924             : }
    5925             : 
    5926           0 : int ext4_change_inode_journal_flag(struct inode *inode, int val)
    5927             : {
    5928           0 :         journal_t *journal;
    5929           0 :         handle_t *handle;
    5930           0 :         int err;
    5931           0 :         int alloc_ctx;
    5932             : 
    5933             :         /*
    5934             :          * We have to be very careful here: changing a data block's
    5935             :          * journaling status dynamically is dangerous.  If we write a
    5936             :          * data block to the journal, change the status and then delete
    5937             :          * that block, we risk forgetting to revoke the old log record
    5938             :          * from the journal and so a subsequent replay can corrupt data.
    5939             :          * So, first we make sure that the journal is empty and that
    5940             :          * nobody is changing anything.
    5941             :          */
    5942             : 
    5943           0 :         journal = EXT4_JOURNAL(inode);
    5944           0 :         if (!journal)
    5945             :                 return 0;
    5946           0 :         if (is_journal_aborted(journal))
    5947             :                 return -EROFS;
    5948             : 
    5949             :         /* Wait for all existing dio workers */
    5950           0 :         inode_dio_wait(inode);
    5951             : 
    5952             :         /*
    5953             :          * Before flushing the journal and switching inode's aops, we have
    5954             :          * to flush all dirty data the inode has. There can be outstanding
    5955             :          * delayed allocations, there can be unwritten extents created by
    5956             :          * fallocate or buffered writes in dioread_nolock mode covered by
    5957             :          * dirty data which can be converted only after flushing the dirty
    5958             :          * data (and journalled aops don't know how to handle these cases).
    5959             :          */
    5960           0 :         if (val) {
    5961           0 :                 filemap_invalidate_lock(inode->i_mapping);
    5962           0 :                 err = filemap_write_and_wait(inode->i_mapping);
    5963           0 :                 if (err < 0) {
    5964           0 :                         filemap_invalidate_unlock(inode->i_mapping);
    5965           0 :                         return err;
    5966             :                 }
    5967             :         }
    5968             : 
    5969           0 :         alloc_ctx = ext4_writepages_down_write(inode->i_sb);
    5970           0 :         jbd2_journal_lock_updates(journal);
    5971             : 
    5972             :         /*
    5973             :          * OK, there are no updates running now, and all cached data is
    5974             :          * synced to disk.  We are now in a completely consistent state
    5975             :          * which doesn't have anything in the journal, and we know that
    5976             :          * no filesystem updates are running, so it is safe to modify
    5977             :          * the inode's in-core data-journaling state flag now.
    5978             :          */
    5979             : 
    5980           0 :         if (val)
    5981           0 :                 ext4_set_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
    5982             :         else {
    5983           0 :                 err = jbd2_journal_flush(journal, 0);
    5984           0 :                 if (err < 0) {
    5985           0 :                         jbd2_journal_unlock_updates(journal);
    5986           0 :                         ext4_writepages_up_write(inode->i_sb, alloc_ctx);
    5987           0 :                         return err;
    5988             :                 }
    5989           0 :                 ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
    5990             :         }
    5991           0 :         ext4_set_aops(inode);
    5992             : 
    5993           0 :         jbd2_journal_unlock_updates(journal);
    5994           0 :         ext4_writepages_up_write(inode->i_sb, alloc_ctx);
    5995             : 
    5996           0 :         if (val)
    5997           0 :                 filemap_invalidate_unlock(inode->i_mapping);
    5998             : 
    5999             :         /* Finally we can mark the inode as dirty. */
    6000             : 
    6001           0 :         handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
    6002           0 :         if (IS_ERR(handle))
    6003           0 :                 return PTR_ERR(handle);
    6004             : 
    6005           0 :         ext4_fc_mark_ineligible(inode->i_sb,
    6006             :                 EXT4_FC_REASON_JOURNAL_FLAG_CHANGE, handle);
    6007           0 :         err = ext4_mark_inode_dirty(handle, inode);
    6008           0 :         ext4_handle_sync(handle);
    6009           0 :         ext4_journal_stop(handle);
    6010           0 :         ext4_std_error(inode->i_sb, err);
    6011             : 
    6012             :         return err;
    6013             : }
    6014             : 
    6015           0 : static int ext4_bh_unmapped(handle_t *handle, struct inode *inode,
    6016             :                             struct buffer_head *bh)
    6017             : {
    6018           0 :         return !buffer_mapped(bh);
    6019             : }
    6020             : 
    6021           0 : vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf)
    6022             : {
    6023           0 :         struct vm_area_struct *vma = vmf->vma;
    6024           0 :         struct folio *folio = page_folio(vmf->page);
    6025           0 :         loff_t size;
    6026           0 :         unsigned long len;
    6027           0 :         int err;
    6028           0 :         vm_fault_t ret;
    6029           0 :         struct file *file = vma->vm_file;
    6030           0 :         struct inode *inode = file_inode(file);
    6031           0 :         struct address_space *mapping = inode->i_mapping;
    6032           0 :         handle_t *handle;
    6033           0 :         get_block_t *get_block;
    6034           0 :         int retries = 0;
    6035             : 
    6036           0 :         if (unlikely(IS_IMMUTABLE(inode)))
    6037             :                 return VM_FAULT_SIGBUS;
    6038             : 
    6039           0 :         sb_start_pagefault(inode->i_sb);
    6040           0 :         file_update_time(vma->vm_file);
    6041             : 
    6042           0 :         filemap_invalidate_lock_shared(mapping);
    6043             : 
    6044           0 :         err = ext4_convert_inline_data(inode);
    6045           0 :         if (err)
    6046           0 :                 goto out_ret;
    6047             : 
    6048             :         /*
    6049             :          * On data journalling we skip straight to the transaction handle:
    6050             :          * there's no delalloc; page truncated will be checked later; the
    6051             :          * early return w/ all buffers mapped (calculates size/len) can't
    6052             :          * be used; and there's no dioread_nolock, so only ext4_get_block.
    6053             :          */
    6054           0 :         if (ext4_should_journal_data(inode))
    6055           0 :                 goto retry_alloc;
    6056             : 
    6057             :         /* Delalloc case is easy... */
    6058           0 :         if (test_opt(inode->i_sb, DELALLOC) &&
    6059           0 :             !ext4_nonda_switch(inode->i_sb)) {
    6060           0 :                 do {
    6061           0 :                         err = block_page_mkwrite(vma, vmf,
    6062             :                                                    ext4_da_get_block_prep);
    6063           0 :                 } while (err == -ENOSPC &&
    6064           0 :                        ext4_should_retry_alloc(inode->i_sb, &retries));
    6065           0 :                 goto out_ret;
    6066             :         }
    6067             : 
    6068           0 :         folio_lock(folio);
    6069           0 :         size = i_size_read(inode);
    6070             :         /* Page got truncated from under us? */
    6071           0 :         if (folio->mapping != mapping || folio_pos(folio) > size) {
    6072           0 :                 folio_unlock(folio);
    6073           0 :                 ret = VM_FAULT_NOPAGE;
    6074           0 :                 goto out;
    6075             :         }
    6076             : 
    6077           0 :         len = folio_size(folio);
    6078           0 :         if (folio_pos(folio) + len > size)
    6079           0 :                 len = size - folio_pos(folio);
    6080             :         /*
    6081             :          * Return if we have all the buffers mapped. This avoids the need to do
    6082             :          * journal_start/journal_stop which can block and take a long time
    6083             :          *
    6084             :          * This cannot be done for data journalling, as we have to add the
    6085             :          * inode to the transaction's list to writeprotect pages on commit.
    6086             :          */
    6087           0 :         if (folio_buffers(folio)) {
    6088           0 :                 if (!ext4_walk_page_buffers(NULL, inode, folio_buffers(folio),
    6089             :                                             0, len, NULL,
    6090             :                                             ext4_bh_unmapped)) {
    6091             :                         /* Wait so that we don't change page under IO */
    6092           0 :                         folio_wait_stable(folio);
    6093           0 :                         ret = VM_FAULT_LOCKED;
    6094           0 :                         goto out;
    6095             :                 }
    6096             :         }
    6097           0 :         folio_unlock(folio);
    6098             :         /* OK, we need to fill the hole... */
    6099           0 :         if (ext4_should_dioread_nolock(inode))
    6100             :                 get_block = ext4_get_block_unwritten;
    6101             :         else
    6102           0 :                 get_block = ext4_get_block;
    6103           0 : retry_alloc:
    6104           0 :         handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE,
    6105             :                                     ext4_writepage_trans_blocks(inode));
    6106           0 :         if (IS_ERR(handle)) {
    6107           0 :                 ret = VM_FAULT_SIGBUS;
    6108           0 :                 goto out;
    6109             :         }
    6110             :         /*
    6111             :          * Data journalling can't use block_page_mkwrite() because it
    6112             :          * will set_buffer_dirty() before do_journal_get_write_access()
    6113             :          * thus might hit warning messages for dirty metadata buffers.
    6114             :          */
    6115           0 :         if (!ext4_should_journal_data(inode)) {
    6116           0 :                 err = block_page_mkwrite(vma, vmf, get_block);
    6117             :         } else {
    6118           0 :                 folio_lock(folio);
    6119           0 :                 size = i_size_read(inode);
    6120             :                 /* Page got truncated from under us? */
    6121           0 :                 if (folio->mapping != mapping || folio_pos(folio) > size) {
    6122           0 :                         ret = VM_FAULT_NOPAGE;
    6123           0 :                         goto out_error;
    6124             :                 }
    6125             : 
    6126           0 :                 len = folio_size(folio);
    6127           0 :                 if (folio_pos(folio) + len > size)
    6128           0 :                         len = size - folio_pos(folio);
    6129             : 
    6130           0 :                 err = __block_write_begin(&folio->page, 0, len, ext4_get_block);
    6131           0 :                 if (!err) {
    6132           0 :                         ret = VM_FAULT_SIGBUS;
    6133           0 :                         if (ext4_journal_folio_buffers(handle, folio, len))
    6134           0 :                                 goto out_error;
    6135             :                 } else {
    6136           0 :                         folio_unlock(folio);
    6137             :                 }
    6138             :         }
    6139           0 :         ext4_journal_stop(handle);
    6140           0 :         if (err == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
    6141           0 :                 goto retry_alloc;
    6142           0 : out_ret:
    6143           0 :         ret = block_page_mkwrite_return(err);
    6144           0 : out:
    6145           0 :         filemap_invalidate_unlock_shared(mapping);
    6146           0 :         sb_end_pagefault(inode->i_sb);
    6147           0 :         return ret;
    6148           0 : out_error:
    6149           0 :         folio_unlock(folio);
    6150           0 :         ext4_journal_stop(handle);
    6151           0 :         goto out;
    6152             : }

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