Messages in this thread Patch in this message | | | Date | Fri, 13 Mar 2009 18:10:08 -0700 | From | Greg KH <> | Subject | [patch 031/114] md/raid10: Dont skip more than 1 bitmap-chunk at a time during recovery. |
| |
2.6.28-stable review patch. If anyone has any objections, please let us know.
------------------
From: NeilBrown <neilb@suse.de>
commit 09b4068a7fe442efc40e9dcbcf5ff37c3338ab15 upstream.
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.
Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- drivers/md/raid10.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -2011,13 +2011,13 @@ static sector_t sync_request(mddev_t *md /* There is nowhere to write, so all non-sync * drives must be failed, so try the next chunk... */ - { - sector_t sec = max_sector - sector_nr; - sectors_skipped += sec; + if (sector_nr + max_sync < max_sector) + max_sector = sector_nr + max_sync; + + sectors_skipped += (max_sector - sector_nr); chunks_skipped ++; sector_nr = max_sector; goto skipped; - } } static int run(mddev_t *mddev)
| |