drivers/md/dm-bio-record.h

   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         int __bi_remaining;
  23         unsigned long bi_flags;
  24         struct bvec_iter bi_iter;
  25         bio_end_io_t *bi_end_io;
  26 #if defined(CONFIG_BLK_DEV_INTEGRITY)
  27         struct bio_integrity_payload *bi_integrity;
  28 #endif
  29 };
  30
  31 static inline void dm_bio_record(struct dm_bio_details *bd, struct bio *bio)
  32 {
  33         bd->bi_bdev = bio->bi_bdev;
  34         bd->bi_flags = bio->bi_flags;
  35         bd->bi_iter = bio->bi_iter;
  36         bd->__bi_remaining = atomic_read(&bio->__bi_remaining);
  37         bd->bi_end_io = bio->bi_end_io;
  38 #if defined(CONFIG_BLK_DEV_INTEGRITY)
  39         bd->bi_integrity = bio_integrity(bio);
  40 #endif
  41 }
  42
  43 static inline void dm_bio_restore(struct dm_bio_details *bd, struct bio *bio)
  44 {
  45         bio->bi_bdev = bd->bi_bdev;
  46         bio->bi_flags = bd->bi_flags;
  47         bio->bi_iter = bd->bi_iter;
  48         atomic_set(&bio->__bi_remaining, bd->__bi_remaining);
  49         bio->bi_end_io = bd->bi_end_io;
  50 #if defined(CONFIG_BLK_DEV_INTEGRITY)
  51         bio->bi_integrity = bd->bi_integrity;
  52 #endif
  53 }
  54
  55 #endif