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 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