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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_IO_READ_H
#define _BCACHEFS_IO_READ_H
#include "bkey_buf.h"
struct bch_read_bio {
struct bch_fs *c;
u64 start_time;
u64 submit_time;
/*
* Reads will often have to be split, and if the extent being read from
* was checksummed or compressed we'll also have to allocate bounce
* buffers and copy the data back into the original bio.
*
* If we didn't have to split, we have to save and restore the original
* bi_end_io - @split below indicates which:
*/
union {
struct bch_read_bio *parent;
bio_end_io_t *end_io;
};
/*
* Saved copy of bio->bi_iter, from submission time - allows us to
* resubmit on IO error, and also to copy data back to the original bio
* when we're bouncing:
*/
struct bvec_iter bvec_iter;
unsigned offset_into_extent;
u16 flags;
union {
struct {
u16 bounce:1,
split:1,
kmalloc:1,
have_ioref:1,
narrow_crcs:1,
hole:1,
retry:2,
context:2;
};
u16 _state;
};
struct bch_devs_list devs_have;
struct extent_ptr_decoded pick;
/*
* pos we read from - different from data_pos for indirect extents:
*/
u32 subvol;
struct bpos read_pos;
/*
* start pos of data we read (may not be pos of data we want) - for
* promote, narrow extents paths:
*/
enum btree_id data_btree;
struct bpos data_pos;
struct bversion version;
struct promote_op *promote;
struct bch_io_opts opts;
struct work_struct work;
struct bio bio;
};
#define to_rbio(_bio) container_of((_bio), struct bch_read_bio, bio)
struct bch_devs_mask;
struct cache_promote_op;
struct extent_ptr_decoded;
int __bch2_read_indirect_extent(struct btree_trans *, unsigned *,
struct bkey_buf *);
static inline int bch2_read_indirect_extent(struct btree_trans *trans,
enum btree_id *data_btree,
unsigned *offset_into_extent,
struct bkey_buf *k)
{
if (k->k->k.type != KEY_TYPE_reflink_p)
return 0;
*data_btree = BTREE_ID_reflink;
return __bch2_read_indirect_extent(trans, offset_into_extent, k);
}
enum bch_read_flags {
BCH_READ_RETRY_IF_STALE = 1 << 0,
BCH_READ_MAY_PROMOTE = 1 << 1,
BCH_READ_USER_MAPPED = 1 << 2,
BCH_READ_NODECODE = 1 << 3,
BCH_READ_LAST_FRAGMENT = 1 << 4,
/* internal: */
BCH_READ_MUST_BOUNCE = 1 << 5,
BCH_READ_MUST_CLONE = 1 << 6,
BCH_READ_IN_RETRY = 1 << 7,
};
int __bch2_read_extent(struct btree_trans *, struct bch_read_bio *,
struct bvec_iter, struct bpos, enum btree_id,
struct bkey_s_c, unsigned,
struct bch_io_failures *, unsigned);
static inline void bch2_read_extent(struct btree_trans *trans,
struct bch_read_bio *rbio, struct bpos read_pos,
enum btree_id data_btree, struct bkey_s_c k,
unsigned offset_into_extent, unsigned flags)
{
__bch2_read_extent(trans, rbio, rbio->bio.bi_iter, read_pos,
data_btree, k, offset_into_extent, NULL, flags);
}
void __bch2_read(struct bch_fs *, struct bch_read_bio *, struct bvec_iter,
subvol_inum, struct bch_io_failures *, unsigned flags);
static inline void bch2_read(struct bch_fs *c, struct bch_read_bio *rbio,
subvol_inum inum)
{
struct bch_io_failures failed = { .nr = 0 };
BUG_ON(rbio->_state);
rbio->c = c;
rbio->start_time = local_clock();
rbio->subvol = inum.subvol;
__bch2_read(c, rbio, rbio->bio.bi_iter, inum, &failed,
BCH_READ_RETRY_IF_STALE|
BCH_READ_MAY_PROMOTE|
BCH_READ_USER_MAPPED);
}
static inline struct bch_read_bio *rbio_init(struct bio *bio,
struct bch_io_opts opts)
{
struct bch_read_bio *rbio = to_rbio(bio);
rbio->_state = 0;
rbio->promote = NULL;
rbio->opts = opts;
return rbio;
}
void bch2_fs_io_read_exit(struct bch_fs *);
int bch2_fs_io_read_init(struct bch_fs *);
#endif /* _BCACHEFS_IO_READ_H */
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