LXR linux/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
  20struct 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
  31static 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
  43static 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
  56