xref: /linux/drivers/md/dm-bio-record.h (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
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 struct dm_bio_details {
20 	sector_t bi_sector;
21 	struct block_device *bi_bdev;
22 	unsigned int bi_size;
23 	unsigned short bi_idx;
24 	unsigned long bi_flags;
25 };
26 
27 static inline void dm_bio_record(struct dm_bio_details *bd, struct bio *bio)
28 {
29 	bd->bi_sector = bio->bi_sector;
30 	bd->bi_bdev = bio->bi_bdev;
31 	bd->bi_size = bio->bi_size;
32 	bd->bi_idx = bio->bi_idx;
33 	bd->bi_flags = bio->bi_flags;
34 }
35 
36 static inline void dm_bio_restore(struct dm_bio_details *bd, struct bio *bio)
37 {
38 	bio->bi_sector = bd->bi_sector;
39 	bio->bi_bdev = bd->bi_bdev;
40 	bio->bi_size = bd->bi_size;
41 	bio->bi_idx = bd->bi_idx;
42 	bio->bi_flags = bd->bi_flags;
43 }
44 
45 #endif
46