[PATCH] md: Calculate correct array size for raid10 in new offset mode

The size calculation made assumtion which the new offset mode didn't
follow.  This gets the size right in all cases.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 4db34edfd87f..7f636283a1ba 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2060,7 +2060,13 @@ static int run(mddev_t *mddev)
         /*
          * Ok, everything is just fine now
          */
-        size = conf->stride * conf->raid_disks;
+        if (conf->far_offset) {
+                size = mddev->size >> (conf->chunk_shift-1);
+                size *= conf->raid_disks;
+                size <<= conf->chunk_shift;
+                sector_div(size, conf->far_copies);
+        } else
+                size = conf->stride * conf->raid_disks;
         sector_div(size, conf->near_copies);
         mddev->array_size = size/2;
         mddev->resync_max_sectors = size;