tree c7d2eb0715e2b12cac4bc2196583a510c234743c
parent 2ec77fc93ca8731368fbe8e71f805c0569d4bcee
author NeilBrown <neilb@suse.de> 1235528327 +1100
committer NeilBrown <neilb@suse.de> 1235528327 +1100

md/raid10:  Don't skip more than 1 bitmap-chunk at a time during recovery.

When doing recovery on a raid10 with a write-intent bitmap, we only
need to recovery chunks that are flagged in the bitmap.

However if we choose to skip a chunk as it isn't flag, the code
currently skips the whole raid10-chunk, thus it might not recovery
some blocks that need recovering.

This patch fixes it.

In case that is confusing, it might help to understand that there
is a 'raid10 chunk size' which guides how data is distributed across
the devices, and a 'bitmap chunk size' which says how much data
corresponds to a single bit in the bitmap.

This bug only affects cases where the bitmap chunk size is smaller
than the raid10 chunk size.


Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>