linux/fs/btrfs/bio.h
Christoph Hellwig 103c19723c btrfs: split the bio submission path into a separate file
The code used by btrfs_submit_bio only interacts with the rest of
volumes.c through __btrfs_map_block (which itself is a more generic
version of two exported helpers) and does not really have anything
to do with volumes.c.  Create a new bio.c file and a bio.h header
going along with it for the btrfs_bio-based storage layer, which
will grow even more going forward.

Also update the file with my copyright notice given that a large
part of the moved code was written or rewritten by me.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-12-05 18:00:57 +01:00

128 lines
3.2 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);
/*
* Additional info to pass along bio.
*
* Mostly for btrfs specific features like csum and mirror_num.
*/
struct btrfs_bio {
unsigned int mirror_num:7;
/*
* Extra indicator for metadata bios.
* For some btrfs bios they use pages without a mapping, thus
* we can not rely on page->mapping->host to determine if
* it's a metadata bio.
*/
unsigned int is_metadata:1;
struct bvec_iter iter;
/* for direct I/O */
u64 file_offset;
/* @device is for stripe IO submission. */
struct btrfs_device *device;
union {
/* For data checksum verification. */
struct {
u8 *csum;
u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
};
/* For metadata 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 read end I/O handling */
struct work_struct end_io_work;
/*
* 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);
struct bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
btrfs_bio_end_io_t end_io, void *private);
struct bio *btrfs_bio_clone_partial(struct bio *orig, u64 offset, u64 size,
btrfs_bio_end_io_t end_io, void *private);
static inline void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status)
{
bbio->bio.bi_status = status;
bbio->end_io(bbio);
}
static inline void btrfs_bio_free_csum(struct btrfs_bio *bbio)
{
if (bbio->is_metadata)
return;
if (bbio->csum != bbio->csum_inline) {
kfree(bbio->csum);
bbio->csum = NULL;
}
}
/*
* Iterate through a btrfs_bio (@bbio) on a per-sector basis.
*
* bvl - struct bio_vec
* bbio - struct btrfs_bio
* iters - struct bvec_iter
* bio_offset - unsigned int
*/
#define btrfs_bio_for_each_sector(fs_info, bvl, bbio, iter, bio_offset) \
for ((iter) = (bbio)->iter, (bio_offset) = 0; \
(iter).bi_size && \
(((bvl) = bio_iter_iovec((&(bbio)->bio), (iter))), 1); \
(bio_offset) += fs_info->sectorsize, \
bio_advance_iter_single(&(bbio)->bio, &(iter), \
(fs_info)->sectorsize))
void btrfs_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
int mirror_num);
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