linux/fs/btrfs/bio.h
Christoph Hellwig ec63b84d46 btrfs: add an ordered_extent pointer to struct btrfs_bio
Add a pointer to the ordered_extent to the existing union in struct
btrfs_bio, so all code dealing with data write bios can just use a
pointer dereference to retrieve the ordered_extent instead of doing
multiple rbtree lookups per I/O.

The reference to this ordered_extent is dropped at end I/O time,
which implies that an extra one must be acquired when the bio is split.
This also requires moving the btrfs_extract_ordered_extent call into
btrfs_split_bio so that the invariant of always having a valid
ordered_extent reference for the btrfs_bio is kept.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2023-06-19 13:59:36 +02:00

112 lines
3.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2007 Oracle. All rights reserved.
* Copyright (C) 2022 Christoph Hellwig.
*/
#ifndef BTRFS_BIO_H
#define BTRFS_BIO_H
#include <linux/bio.h>
#include <linux/workqueue.h>
#include "tree-checker.h"
struct btrfs_bio;
struct btrfs_fs_info;
#define BTRFS_BIO_INLINE_CSUM_SIZE 64
/*
* Maximum number of sectors for a single bio to limit the size of the
* checksum array. This matches the number of bio_vecs per bio and thus the
* I/O size for buffered I/O.
*/
#define BTRFS_MAX_BIO_SECTORS (256)
typedef void (*btrfs_bio_end_io_t)(struct btrfs_bio *bbio);
/*
* Highlevel btrfs I/O structure. It is allocated by btrfs_bio_alloc and
* passed to btrfs_submit_bio for mapping to the physical devices.
*/
struct btrfs_bio {
/*
* Inode and offset into it that this I/O operates on.
* Only set for data I/O.
*/
struct btrfs_inode *inode;
u64 file_offset;
union {
/*
* For data reads: checksumming and original I/O information.
* (for internal use in the btrfs_submit_bio machinery only)
*/
struct {
u8 *csum;
u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
struct bvec_iter saved_iter;
};
/*
* For data writes:
* - ordered extent covering the bio
* - pointer to the checksums for this bio
* - original physical address from the allocator
* (for zone append only)
*/
struct {
struct btrfs_ordered_extent *ordered;
struct btrfs_ordered_sum *sums;
u64 orig_physical;
};
/* For metadata reads: parentness verification. */
struct btrfs_tree_parent_check parent_check;
};
/* End I/O information supplied to btrfs_bio_alloc */
btrfs_bio_end_io_t end_io;
void *private;
/* For internal use in read end I/O handling */
unsigned int mirror_num;
atomic_t pending_ios;
struct work_struct end_io_work;
/* File system that this I/O operates on. */
struct btrfs_fs_info *fs_info;
/*
* This member must come last, bio_alloc_bioset will allocate enough
* bytes for entire btrfs_bio but relies on bio being last.
*/
struct bio bio;
};
static inline struct btrfs_bio *btrfs_bio(struct bio *bio)
{
return container_of(bio, struct btrfs_bio, bio);
}
int __init btrfs_bioset_init(void);
void __cold btrfs_bioset_exit(void);
void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info,
btrfs_bio_end_io_t end_io, void *private);
struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
struct btrfs_fs_info *fs_info,
btrfs_bio_end_io_t end_io, void *private);
void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status);
/* Submit using blkcg_punt_bio_submit. */
#define REQ_BTRFS_CGROUP_PUNT REQ_FS_PRIVATE
void btrfs_submit_bio(struct btrfs_bio *bbio, int mirror_num);
void btrfs_submit_repair_write(struct btrfs_bio *bbio, int mirror_num, bool dev_replace);
int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
u64 length, u64 logical, struct page *page,
unsigned int pg_offset, int mirror_num);
#endif