xref: /linux/drivers/md/dm-bio-record.h (revision c0c914eca7f251c70facc37dfebeaf176601918d)
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 block_device *bi_bdev;
22 	unsigned long bi_flags;
23 	struct bvec_iter bi_iter;
24 };
25 
26 static inline void dm_bio_record(struct dm_bio_details *bd, struct bio *bio)
27 {
28 	bd->bi_bdev = bio->bi_bdev;
29 	bd->bi_flags = bio->bi_flags;
30 	bd->bi_iter = bio->bi_iter;
31 }
32 
33 static inline void dm_bio_restore(struct dm_bio_details *bd, struct bio *bio)
34 {
35 	bio->bi_bdev = bd->bi_bdev;
36 	bio->bi_flags = bd->bi_flags;
37 	bio->bi_iter = bd->bi_iter;
38 }
39 
40 #endif
41