Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0 */
       2             : /*
       3             :  * Copyright (C) 2007 Oracle.  All rights reserved.
       4             :  */
       5             : 
       6             : #ifndef BTRFS_TRANSACTION_H
       7             : #define BTRFS_TRANSACTION_H
       8             : 
       9             : #include <linux/refcount.h>
      10             : #include "btrfs_inode.h"
      11             : #include "delayed-ref.h"
      12             : #include "ctree.h"
      13             : #include "misc.h"
      14             : 
      15             : enum btrfs_trans_state {
      16             :         TRANS_STATE_RUNNING,
      17             :         TRANS_STATE_COMMIT_START,
      18             :         TRANS_STATE_COMMIT_DOING,
      19             :         TRANS_STATE_UNBLOCKED,
      20             :         TRANS_STATE_SUPER_COMMITTED,
      21             :         TRANS_STATE_COMPLETED,
      22             :         TRANS_STATE_MAX,
      23             : };
      24             : 
      25             : #define BTRFS_TRANS_HAVE_FREE_BGS       0
      26             : #define BTRFS_TRANS_DIRTY_BG_RUN        1
      27             : #define BTRFS_TRANS_CACHE_ENOSPC        2
      28             : 
      29             : struct btrfs_transaction {
      30             :         u64 transid;
      31             :         /*
      32             :          * total external writers(USERSPACE/START/ATTACH) in this
      33             :          * transaction, it must be zero before the transaction is
      34             :          * being committed
      35             :          */
      36             :         atomic_t num_extwriters;
      37             :         /*
      38             :          * total writers in this transaction, it must be zero before the
      39             :          * transaction can end
      40             :          */
      41             :         atomic_t num_writers;
      42             :         refcount_t use_count;
      43             : 
      44             :         unsigned long flags;
      45             : 
      46             :         /* Be protected by fs_info->trans_lock when we want to change it. */
      47             :         enum btrfs_trans_state state;
      48             :         int aborted;
      49             :         struct list_head list;
      50             :         struct extent_io_tree dirty_pages;
      51             :         time64_t start_time;
      52             :         wait_queue_head_t writer_wait;
      53             :         wait_queue_head_t commit_wait;
      54             :         struct list_head pending_snapshots;
      55             :         struct list_head dev_update_list;
      56             :         struct list_head switch_commits;
      57             :         struct list_head dirty_bgs;
      58             : 
      59             :         /*
      60             :          * There is no explicit lock which protects io_bgs, rather its
      61             :          * consistency is implied by the fact that all the sites which modify
      62             :          * it do so under some form of transaction critical section, namely:
      63             :          *
      64             :          * - btrfs_start_dirty_block_groups - This function can only ever be
      65             :          *   run by one of the transaction committers. Refer to
      66             :          *   BTRFS_TRANS_DIRTY_BG_RUN usage in btrfs_commit_transaction
      67             :          *
      68             :          * - btrfs_write_dirty_blockgroups - this is called by
      69             :          *   commit_cowonly_roots from transaction critical section
      70             :          *   (TRANS_STATE_COMMIT_DOING)
      71             :          *
      72             :          * - btrfs_cleanup_dirty_bgs - called on transaction abort
      73             :          */
      74             :         struct list_head io_bgs;
      75             :         struct list_head dropped_roots;
      76             :         struct extent_io_tree pinned_extents;
      77             : 
      78             :         /*
      79             :          * we need to make sure block group deletion doesn't race with
      80             :          * free space cache writeout.  This mutex keeps them from stomping
      81             :          * on each other
      82             :          */
      83             :         struct mutex cache_write_mutex;
      84             :         spinlock_t dirty_bgs_lock;
      85             :         /* Protected by spin lock fs_info->unused_bgs_lock. */
      86             :         struct list_head deleted_bgs;
      87             :         spinlock_t dropped_roots_lock;
      88             :         struct btrfs_delayed_ref_root delayed_refs;
      89             :         struct btrfs_fs_info *fs_info;
      90             : 
      91             :         /*
      92             :          * Number of ordered extents the transaction must wait for before
      93             :          * committing. These are ordered extents started by a fast fsync.
      94             :          */
      95             :         atomic_t pending_ordered;
      96             :         wait_queue_head_t pending_wait;
      97             : };
      98             : 
      99             : enum {
     100             :         ENUM_BIT(__TRANS_FREEZABLE),
     101             :         ENUM_BIT(__TRANS_START),
     102             :         ENUM_BIT(__TRANS_ATTACH),
     103             :         ENUM_BIT(__TRANS_JOIN),
     104             :         ENUM_BIT(__TRANS_JOIN_NOLOCK),
     105             :         ENUM_BIT(__TRANS_DUMMY),
     106             :         ENUM_BIT(__TRANS_JOIN_NOSTART),
     107             : };
     108             : 
     109             : #define TRANS_START             (__TRANS_START | __TRANS_FREEZABLE)
     110             : #define TRANS_ATTACH            (__TRANS_ATTACH)
     111             : #define TRANS_JOIN              (__TRANS_JOIN | __TRANS_FREEZABLE)
     112             : #define TRANS_JOIN_NOLOCK       (__TRANS_JOIN_NOLOCK)
     113             : #define TRANS_JOIN_NOSTART      (__TRANS_JOIN_NOSTART)
     114             : 
     115             : #define TRANS_EXTWRITERS        (__TRANS_START | __TRANS_ATTACH)
     116             : 
     117             : struct btrfs_trans_handle {
     118             :         u64 transid;
     119             :         u64 bytes_reserved;
     120             :         u64 chunk_bytes_reserved;
     121             :         unsigned long delayed_ref_updates;
     122             :         struct btrfs_transaction *transaction;
     123             :         struct btrfs_block_rsv *block_rsv;
     124             :         struct btrfs_block_rsv *orig_rsv;
     125             :         /* Set by a task that wants to create a snapshot. */
     126             :         struct btrfs_pending_snapshot *pending_snapshot;
     127             :         refcount_t use_count;
     128             :         unsigned int type;
     129             :         /*
     130             :          * Error code of transaction abort, set outside of locks and must use
     131             :          * the READ_ONCE/WRITE_ONCE access
     132             :          */
     133             :         short aborted;
     134             :         bool adding_csums;
     135             :         bool allocating_chunk;
     136             :         bool removing_chunk;
     137             :         bool reloc_reserved;
     138             :         bool in_fsync;
     139             :         struct btrfs_fs_info *fs_info;
     140             :         struct list_head new_bgs;
     141             : };
     142             : 
     143             : /*
     144             :  * The abort status can be changed between calls and is not protected by locks.
     145             :  * This accepts btrfs_transaction and btrfs_trans_handle as types. Once it's
     146             :  * set to a non-zero value it does not change, so the macro should be in checks
     147             :  * but is not necessary for further reads of the value.
     148             :  */
     149             : #define TRANS_ABORTED(trans)            (unlikely(READ_ONCE((trans)->aborted)))
     150             : 
     151             : struct btrfs_pending_snapshot {
     152             :         struct dentry *dentry;
     153             :         struct inode *dir;
     154             :         struct btrfs_root *root;
     155             :         struct btrfs_root_item *root_item;
     156             :         struct btrfs_root *snap;
     157             :         struct btrfs_qgroup_inherit *inherit;
     158             :         struct btrfs_path *path;
     159             :         /* block reservation for the operation */
     160             :         struct btrfs_block_rsv block_rsv;
     161             :         /* extra metadata reservation for relocation */
     162             :         int error;
     163             :         /* Preallocated anonymous block device number */
     164             :         dev_t anon_dev;
     165             :         bool readonly;
     166             :         struct list_head list;
     167             : };
     168             : 
     169           0 : static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
     170             :                                               struct btrfs_inode *inode)
     171             : {
     172           0 :         spin_lock(&inode->lock);
     173           0 :         inode->last_trans = trans->transaction->transid;
     174           0 :         inode->last_sub_trans = inode->root->log_transid;
     175           0 :         inode->last_log_commit = inode->last_sub_trans - 1;
     176           0 :         spin_unlock(&inode->lock);
     177           0 : }
     178             : 
     179             : /*
     180             :  * Make qgroup codes to skip given qgroupid, means the old/new_roots for
     181             :  * qgroup won't contain the qgroupid in it.
     182             :  */
     183           0 : static inline void btrfs_set_skip_qgroup(struct btrfs_trans_handle *trans,
     184             :                                          u64 qgroupid)
     185             : {
     186           0 :         struct btrfs_delayed_ref_root *delayed_refs;
     187             : 
     188           0 :         delayed_refs = &trans->transaction->delayed_refs;
     189           0 :         WARN_ON(delayed_refs->qgroup_to_skip);
     190           0 :         delayed_refs->qgroup_to_skip = qgroupid;
     191           0 : }
     192             : 
     193           0 : static inline void btrfs_clear_skip_qgroup(struct btrfs_trans_handle *trans)
     194             : {
     195           0 :         struct btrfs_delayed_ref_root *delayed_refs;
     196             : 
     197           0 :         delayed_refs = &trans->transaction->delayed_refs;
     198           0 :         WARN_ON(!delayed_refs->qgroup_to_skip);
     199           0 :         delayed_refs->qgroup_to_skip = 0;
     200           0 : }
     201             : 
     202             : bool __cold abort_should_print_stack(int errno);
     203             : 
     204             : /*
     205             :  * Call btrfs_abort_transaction as early as possible when an error condition is
     206             :  * detected, that way the exact stack trace is reported for some errors.
     207             :  */
     208             : #define btrfs_abort_transaction(trans, errno)           \
     209             : do {                                                            \
     210             :         bool first = false;                                     \
     211             :         /* Report first abort since mount */                    \
     212             :         if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED,     \
     213             :                         &((trans)->fs_info->fs_state))) {     \
     214             :                 first = true;                                   \
     215             :                 if (WARN(abort_should_print_stack(errno),       \
     216             :                         KERN_ERR                                \
     217             :                         "BTRFS: Transaction aborted (error %d)\n",    \
     218             :                         (errno))) {                                     \
     219             :                         /* Stack trace printed. */                      \
     220             :                 } else {                                                \
     221             :                         btrfs_debug((trans)->fs_info,                        \
     222             :                                     "Transaction aborted (error %d)", \
     223             :                                   (errno));                     \
     224             :                 }                                               \
     225             :         }                                                       \
     226             :         __btrfs_abort_transaction((trans), __func__,            \
     227             :                                   __LINE__, (errno), first);    \
     228             : } while (0)
     229             : 
     230             : int btrfs_end_transaction(struct btrfs_trans_handle *trans);
     231             : struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
     232             :                                                    unsigned int num_items);
     233             : struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
     234             :                                         struct btrfs_root *root,
     235             :                                         unsigned int num_items);
     236             : struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
     237             : struct btrfs_trans_handle *btrfs_join_transaction_spacecache(struct btrfs_root *root);
     238             : struct btrfs_trans_handle *btrfs_join_transaction_nostart(struct btrfs_root *root);
     239             : struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
     240             : struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
     241             :                                         struct btrfs_root *root);
     242             : int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
     243             : 
     244             : void btrfs_add_dead_root(struct btrfs_root *root);
     245             : int btrfs_defrag_root(struct btrfs_root *root);
     246             : void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info);
     247             : int btrfs_clean_one_deleted_snapshot(struct btrfs_fs_info *fs_info);
     248             : int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
     249             : void btrfs_commit_transaction_async(struct btrfs_trans_handle *trans);
     250             : int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans);
     251             : bool btrfs_should_end_transaction(struct btrfs_trans_handle *trans);
     252             : void btrfs_throttle(struct btrfs_fs_info *fs_info);
     253             : int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
     254             :                                 struct btrfs_root *root);
     255             : int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info,
     256             :                                 struct extent_io_tree *dirty_pages, int mark);
     257             : int btrfs_wait_tree_log_extents(struct btrfs_root *root, int mark);
     258             : int btrfs_transaction_blocked(struct btrfs_fs_info *info);
     259             : int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
     260             : void btrfs_put_transaction(struct btrfs_transaction *transaction);
     261             : void btrfs_add_dropped_root(struct btrfs_trans_handle *trans,
     262             :                             struct btrfs_root *root);
     263             : void btrfs_trans_release_chunk_metadata(struct btrfs_trans_handle *trans);
     264             : void __cold __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
     265             :                                       const char *function,
     266             :                                       unsigned int line, int errno, bool first_hit);
     267             : 
     268             : int __init btrfs_transaction_init(void);
     269             : void __cold btrfs_transaction_exit(void);
     270             : 
     271             : #endif