[PATCH] md: fix for raid6 reshape
Recent patch for raid6 reshape had a change missing that showed up in
subsequent review.
Many places in the raid5 code used "conf->raid_disks-1" to mean "number of
data disks". With raid6 that had to be changed to "conf->raid_disk -
conf->max_degraded" or similar. One place was missed.
This bug means that if a raid6 reshape were aborted in the middle the
recorded position would be wrong. On restart it would either fail (as the
position wasn't on an appropriate boundary) or would leave a section of the
array unreshaped, causing data corruption.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index d247429..54a1ad5 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3071,7 +3071,7 @@
release_stripe(sh);
}
spin_lock_irq(&conf->device_lock);
- conf->expand_progress = (sector_nr + i)*(conf->raid_disks-1);
+ conf->expand_progress = (sector_nr + i) * new_data_disks;
spin_unlock_irq(&conf->device_lock);
/* Ok, those stripe are ready. We can start scheduling
* reads on the source stripes.