dm: raid fix device status indicator when array initializing

When devices in a RAID array are not in-sync, they are supposed to be
reported as such in the status output as an 'a' character, which means
"alive, but not in-sync".  But when the entire array is rebuilt 'A' is
being used, which is incorrect.  This patch corrects this to 'a'.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 37 insertions, 11 deletions

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 86df8b2cf927..7503a20d04a7 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -1017,30 +1017,56 @@ static int raid_status(struct dm_target *ti, status_type_t type,
         struct raid_set *rs = ti->private;
         unsigned raid_param_cnt = 1; /* at least 1 for chunksize */
         unsigned sz = 0;
-        int i;
+        int i, array_in_sync = 0;
         sector_t sync;
 
         switch (type) {
         case STATUSTYPE_INFO:
                 DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks);
 
-                for (i = 0; i < rs->md.raid_disks; i++) {
-                        if (test_bit(Faulty, &rs->dev[i].rdev.flags))
-                                DMEMIT("D");
-                        else if (test_bit(In_sync, &rs->dev[i].rdev.flags))
-                                DMEMIT("A");
-                        else
-                                DMEMIT("a");
-                }
-
                 if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery))
                         sync = rs->md.curr_resync_completed;
                 else
                         sync = rs->md.recovery_cp;
 
-                if (sync > rs->md.resync_max_sectors)
+                if (sync >= rs->md.resync_max_sectors) {
+                        array_in_sync = 1;
                         sync = rs->md.resync_max_sectors;
+                } else {
+                        /*
+                         * The array may be doing an initial sync, or it may
+                         * be rebuilding individual components.  If all the
+                         * devices are In_sync, then it is the array that is
+                         * being initialized.
+                         */
+                        for (i = 0; i < rs->md.raid_disks; i++)
+                                if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
+                                        array_in_sync = 1;
+                }
+                /*
+                 * Status characters:
+                 *  'D' = Dead/Failed device
+                 *  'a' = Alive but not in-sync
+                 *  'A' = Alive and in-sync
+                 */
+                for (i = 0; i < rs->md.raid_disks; i++) {
+                        if (test_bit(Faulty, &rs->dev[i].rdev.flags))
+                                DMEMIT("D");
+                        else if (!array_in_sync ||
+                                 !test_bit(In_sync, &rs->dev[i].rdev.flags))
+                                DMEMIT("a");
+                        else
+                                DMEMIT("A");
+                }
 
+                /*
+                 * In-sync ratio:
+                 *  The in-sync ratio shows the progress of:
+                 *   - Initializing the array
+                 *   - Rebuilding a subset of devices of the array
+                 *  The user can distinguish between the two by referring
+                 *  to the status characters.
+                 */
                 DMEMIT(" %llu/%llu",
                        (unsigned long long) sync,
                        (unsigned long long) rs->md.resync_max_sectors);