xref: /openbmc/linux/drivers/md/dm-bio-record.h (revision bd4af432)
1 /*
2  * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
3  *
4  * This file is released under the GPL.
5  */
6 
7 #ifndef DM_BIO_RECORD_H
8 #define DM_BIO_RECORD_H
9 
10 #include <linux/bio.h>
11 
12 /*
13  * There are lots of mutable fields in the bio struct that get
14  * changed by the lower levels of the block layer.  Some targets,
15  * such as multipath, may wish to resubmit a bio on error.  The
16  * functions in this file help the target record and restore the
17  * original bio state.
18  */
19 
20 struct dm_bio_details {
21 	struct gendisk *bi_disk;
22 	u8 bi_partno;
23 	int __bi_remaining;
24 	unsigned long bi_flags;
25 	struct bvec_iter bi_iter;
26 	bio_end_io_t *bi_end_io;
27 #if defined(CONFIG_BLK_DEV_INTEGRITY)
28 	struct bio_integrity_payload *bi_integrity;
29 #endif
30 };
31 
32 static inline void dm_bio_record(struct dm_bio_details *bd, struct bio *bio)
33 {
34 	bd->bi_disk = bio->bi_disk;
35 	bd->bi_partno = bio->bi_partno;
36 	bd->bi_flags = bio->bi_flags;
37 	bd->bi_iter = bio->bi_iter;
38 	bd->__bi_remaining = atomic_read(&bio->__bi_remaining);
39 	bd->bi_end_io = bio->bi_end_io;
40 #if defined(CONFIG_BLK_DEV_INTEGRITY)
41 	bd->bi_integrity = bio_integrity(bio);
42 #endif
43 }
44 
45 static inline void dm_bio_restore(struct dm_bio_details *bd, struct bio *bio)
46 {
47 	bio->bi_disk = bd->bi_disk;
48 	bio->bi_partno = bd->bi_partno;
49 	bio->bi_flags = bd->bi_flags;
50 	bio->bi_iter = bd->bi_iter;
51 	atomic_set(&bio->__bi_remaining, bd->__bi_remaining);
52 	bio->bi_end_io = bd->bi_end_io;
53 #if defined(CONFIG_BLK_DEV_INTEGRITY)
54 	bio->bi_integrity = bd->bi_integrity;
55 #endif
56 }
57 
58 #endif
59