Commit af03b8e4 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

md: fix two raid10 bugs 



1/ When resyncing a degraded raid10 which has more than 2 copies of each block,
  garbage can get synced on top of good data.

2/ We round the wrong way in part of the device size calculation, which
  can cause confusion.

Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent edad01e2

drivers/md/raid10.c

+6 −0
Original line number Diff line number Diff line
@@ -1867,6 +1867,7 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i 
			int d = r10_bio->devs[i].devnum;

			bio = r10_bio->devs[i].bio;

			bio->bi_end_io = NULL;

			clear_bit(BIO_UPTODATE, &bio->bi_flags);

			if (conf->mirrors[d].rdev == NULL ||

			    test_bit(Faulty, &conf->mirrors[d].rdev->flags))

				continue;
@@ -2037,6 +2038,11 @@ static int run(mddev_t *mddev) 
	/* 'size' is now the number of chunks in the array */

	/* calculate "used chunks per device" in 'stride' */

	stride = size * conf->copies;



	/* We need to round up when dividing by raid_disks to

	 * get the stride size.

	 */

	stride += conf->raid_disks - 1;

	sector_div(stride, conf->raid_disks);

	mddev->size = stride  << (conf->chunk_shift-1);