btrfs scrub: bugfix: mirror_num off by one
Fix the mirror_num determination in scrub_stripe. The rest of the scrub code
did not use mirror_num for anything important and that error went unnoticed.
The nodatasum fixup patch of this set depends on a correct mirror_num.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 221fd5c..59caf8f 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -452,7 +452,7 @@
* first find a good copy
*/
for (i = 0; i < multi->num_stripes; ++i) {
- if (i == sbio->spag[ix].mirror_num)
+ if (i + 1 == sbio->spag[ix].mirror_num)
continue;
if (scrub_fixup_io(READ, multi->stripes[i].dev->bdev,
@@ -930,21 +930,21 @@
if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
offset = map->stripe_len * num;
increment = map->stripe_len * map->num_stripes;
- mirror_num = 0;
+ mirror_num = 1;
} else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
int factor = map->num_stripes / map->sub_stripes;
offset = map->stripe_len * (num / map->sub_stripes);
increment = map->stripe_len * factor;
- mirror_num = num % map->sub_stripes;
+ mirror_num = num % map->sub_stripes + 1;
} else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
increment = map->stripe_len;
- mirror_num = num % map->num_stripes;
+ mirror_num = num % map->num_stripes + 1;
} else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
increment = map->stripe_len;
- mirror_num = num % map->num_stripes;
+ mirror_num = num % map->num_stripes + 1;
} else {
increment = map->stripe_len;
- mirror_num = 0;
+ mirror_num = 1;
}
path = btrfs_alloc_path();