From 761becff016b82a6a7a1b2ef224248da5f46bae9 Mon Sep 17 00:00:00 2001 From: Jonathan Brassow Date: Thu, 11 Oct 2012 13:42:19 +1100 Subject: DM RAID: Fix for "sync" directive ineffectiveness There are two table arguments that can be given to a DM RAID target that control whether the array is forced to (re)synchronize or skip initialization: "sync" and "nosync". When "sync" is given, we set mddev->recovery_cp to 0 in order to cause the device to resynchronize. This is insufficient if there is a bitmap in use, because the array will simply look at the bitmap and see that there is no recovery necessary. The fix is to skip over the loading of the superblocks when "sync" is given, causing new superblocks to be written that will force the array to go through initialization (i.e. synchronization). Signed-off-by: Jonathan Brassow Signed-off-by: NeilBrown --- drivers/md/dm-raid.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/md/dm-raid.c') diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 89a06a36133..45d94a7e7f6 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -1017,6 +1017,19 @@ static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) freshest = NULL; rdev_for_each_safe(rdev, tmp, mddev) { + /* + * Skipping super_load due to DMPF_SYNC will cause + * the array to undergo initialization again as + * though it were new. This is the intended effect + * of the "sync" directive. + * + * When reshaping capability is added, we must ensure + * that the "sync" directive is disallowed during the + * reshape. + */ + if (rs->print_flags & DMPF_SYNC) + continue; + if (!rdev->meta_bdev) continue; -- cgit v1.2.3-70-g09d2