projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
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 | */ | |
| a920f6b3 MP |
19 | |
| 20 | struct dm_bio_vec_details { | |
| 21 | #if PAGE_SIZE < 65536 | |
| 22 | __u16 bv_len; | |
| 23 | __u16 bv_offset; | |
| 24 | #else | |
| 25 | unsigned bv_len; | |
| 26 | unsigned bv_offset; | |
| 27 | #endif | |
| 28 | }; | |
| 29 | ||
| 1da177e4 LT |
30 | struct dm_bio_details { |
| 31 | sector_t bi_sector; | |
| 32 | struct block_device *bi_bdev; | |
| 33 | unsigned int bi_size; | |
| 34 | unsigned short bi_idx; | |
| 35 | unsigned long bi_flags; | |
| a920f6b3 | 36 | struct dm_bio_vec_details bi_io_vec[BIO_MAX_PAGES]; |
| 1da177e4 LT |
37 | }; |
| 38 | ||
| 39 | static inline void dm_bio_record(struct dm_bio_details *bd, struct bio *bio) | |
| 40 | { | |
| a920f6b3 MP |
41 | unsigned i; |
| 42 | ||
| 1da177e4 LT |
43 | bd->bi_sector = bio->bi_sector; |
| 44 | bd->bi_bdev = bio->bi_bdev; | |
| 45 | bd->bi_size = bio->bi_size; | |
| 46 | bd->bi_idx = bio->bi_idx; | |
| 47 | bd->bi_flags = bio->bi_flags; | |
| a920f6b3 MP |
48 | |
| 49 | for (i = 0; i < bio->bi_vcnt; i++) { | |
| 50 | bd->bi_io_vec[i].bv_len = bio->bi_io_vec[i].bv_len; | |
| 51 | bd->bi_io_vec[i].bv_offset = bio->bi_io_vec[i].bv_offset; | |
| 52 | } | |
| 1da177e4 LT |
53 | } |
| 54 | ||
| 55 | static inline void dm_bio_restore(struct dm_bio_details *bd, struct bio *bio) | |
| 56 | { | |
| a920f6b3 MP |
57 | unsigned i; |
| 58 | ||
| 1da177e4 LT |
59 | bio->bi_sector = bd->bi_sector; |
| 60 | bio->bi_bdev = bd->bi_bdev; | |
| 61 | bio->bi_size = bd->bi_size; | |
| 62 | bio->bi_idx = bd->bi_idx; | |
| 63 | bio->bi_flags = bd->bi_flags; | |
| a920f6b3 MP |
64 | |
| 65 | for (i = 0; i < bio->bi_vcnt; i++) { | |
| 66 | bio->bi_io_vec[i].bv_len = bd->bi_io_vec[i].bv_len; | |
| 67 | bio->bi_io_vec[i].bv_offset = bd->bi_io_vec[i].bv_offset; | |
| 68 | } | |
| 1da177e4 LT |
69 | } |
| 70 | ||
| 71 | #endif |