[PATCH] md: fix up maintenance of ->degraded in multipath

A recent fix which made sure ->degraded was initialised properly exposed a
second bug - ->degraded wasn't been updated when drives failed or were
hot-added.

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, 2 insertions, 0 deletions

diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index a6260f0e3b9e..14da37fee37b 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -277,6 +277,7 @@ static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev)
                         set_bit(Faulty, &rdev->flags);
                         set_bit(MD_CHANGE_DEVS, &mddev->flags);
                         conf->working_disks--;
+                        mddev->degraded++;
                         printk(KERN_ALERT "multipath: IO failure on %s,"
                                 " disabling IO path. \n Operation continuing"
                                 " on %d IO paths.\n",
@@ -336,6 +337,7 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
                                 blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
                         conf->working_disks++;
+                        mddev->degraded--;
                         rdev->raid_disk = path;
                         set_bit(In_sync, &rdev->flags);
                         rcu_assign_pointer(p->rdev, rdev);