Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0 */
       2             : /*
       3             :  * Copyright (C) 2007 Oracle.  All rights reserved.
       4             :  * Copyright (C) 2022 Christoph Hellwig.
       5             :  */
       6             : 
       7             : #ifndef BTRFS_BIO_H
       8             : #define BTRFS_BIO_H
       9             : 
      10             : #include <linux/bio.h>
      11             : #include <linux/workqueue.h>
      12             : #include "tree-checker.h"
      13             : 
      14             : struct btrfs_bio;
      15             : struct btrfs_fs_info;
      16             : 
      17             : #define BTRFS_BIO_INLINE_CSUM_SIZE      64
      18             : 
      19             : /*
      20             :  * Maximum number of sectors for a single bio to limit the size of the
      21             :  * checksum array.  This matches the number of bio_vecs per bio and thus the
      22             :  * I/O size for buffered I/O.
      23             :  */
      24             : #define BTRFS_MAX_BIO_SECTORS           (256)
      25             : 
      26             : typedef void (*btrfs_bio_end_io_t)(struct btrfs_bio *bbio);
      27             : 
      28             : /*
      29             :  * Highlevel btrfs I/O structure.  It is allocated by btrfs_bio_alloc and
      30             :  * passed to btrfs_submit_bio for mapping to the physical devices.
      31             :  */
      32             : struct btrfs_bio {
      33             :         /*
      34             :          * Inode and offset into it that this I/O operates on.
      35             :          * Only set for data I/O.
      36             :          */
      37             :         struct btrfs_inode *inode;
      38             :         u64 file_offset;
      39             : 
      40             :         union {
      41             :                 /*
      42             :                  * For data reads: checksumming and original I/O information.
      43             :                  * (for internal use in the btrfs_submit_bio machinery only)
      44             :                  */
      45             :                 struct {
      46             :                         u8 *csum;
      47             :                         u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
      48             :                         struct bvec_iter saved_iter;
      49             :                 };
      50             : 
      51             :                 /*
      52             :                  * For data writes:
      53             :                  * - ordered extent covering the bio
      54             :                  * - pointer to the checksums for this bio
      55             :                  * - original physical address from the allocator
      56             :                  *   (for zone append only)
      57             :                  */
      58             :                 struct {
      59             :                         struct btrfs_ordered_extent *ordered;
      60             :                         struct btrfs_ordered_sum *sums;
      61             :                         u64 orig_physical;
      62             :                 };
      63             : 
      64             :                 /* For metadata reads: parentness verification. */
      65             :                 struct btrfs_tree_parent_check parent_check;
      66             :         };
      67             : 
      68             :         /* End I/O information supplied to btrfs_bio_alloc */
      69             :         btrfs_bio_end_io_t end_io;
      70             :         void *private;
      71             : 
      72             :         /* For internal use in read end I/O handling */
      73             :         unsigned int mirror_num;
      74             :         atomic_t pending_ios;
      75             :         struct work_struct end_io_work;
      76             : 
      77             :         /* File system that this I/O operates on. */
      78             :         struct btrfs_fs_info *fs_info;
      79             : 
      80             :         /*
      81             :          * This member must come last, bio_alloc_bioset will allocate enough
      82             :          * bytes for entire btrfs_bio but relies on bio being last.
      83             :          */
      84             :         struct bio bio;
      85             : };
      86             : 
      87             : static inline struct btrfs_bio *btrfs_bio(struct bio *bio)
      88             : {
      89    29574277 :         return container_of(bio, struct btrfs_bio, bio);
      90             : }
      91             : 
      92             : int __init btrfs_bioset_init(void);
      93             : void __cold btrfs_bioset_exit(void);
      94             : 
      95             : void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info,
      96             :                     btrfs_bio_end_io_t end_io, void *private);
      97             : struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
      98             :                                   struct btrfs_fs_info *fs_info,
      99             :                                   btrfs_bio_end_io_t end_io, void *private);
     100             : void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status);
     101             : 
     102             : /* Submit using blkcg_punt_bio_submit. */
     103             : #define REQ_BTRFS_CGROUP_PUNT                   REQ_FS_PRIVATE
     104             : 
     105             : void btrfs_submit_bio(struct btrfs_bio *bbio, int mirror_num);
     106             : void btrfs_submit_repair_write(struct btrfs_bio *bbio, int mirror_num, bool dev_replace);
     107             : int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
     108             :                             u64 length, u64 logical, struct page *page,
     109             :                             unsigned int pg_offset, int mirror_num);
     110             : 
     111             : #endif