md: fix bug with linear hot-add and elsewhere
Adding a drive to a linear array seems to have stopped working, due to changes
elsewhere in md, and insufficient ongoing testing...
So the patch to make linear hot-add work in the first place introduced a
subtle bug elsewhere that interracts poorly with older version of mdadm.
This fixes it all up.
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/md.c b/drivers/md/md.c
index c10ce91..1c54f3c 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1298,8 +1298,9 @@
ITERATE_RDEV(mddev,rdev2,tmp)
if (rdev2->desc_nr+1 > max_dev)
max_dev = rdev2->desc_nr+1;
-
- sb->max_dev = cpu_to_le32(max_dev);
+
+ if (max_dev > le32_to_cpu(sb->max_dev))
+ sb->max_dev = cpu_to_le32(max_dev);
for (i=0; i<max_dev;i++)
sb->dev_roles[i] = cpu_to_le16(0xfffe);
@@ -1365,10 +1366,14 @@
}
/* make sure rdev->size exceeds mddev->size */
if (rdev->size && (mddev->size == 0 || rdev->size < mddev->size)) {
- if (mddev->pers)
- /* Cannot change size, so fail */
- return -ENOSPC;
- else
+ if (mddev->pers) {
+ /* Cannot change size, so fail
+ * If mddev->level <= 0, then we don't care
+ * about aligning sizes (e.g. linear)
+ */
+ if (mddev->level > 0)
+ return -ENOSPC;
+ } else
mddev->size = rdev->size;
}
@@ -2142,6 +2147,9 @@
rdev->desc_nr = i++;
rdev->raid_disk = rdev->desc_nr;
set_bit(In_sync, &rdev->flags);
+ } else if (rdev->raid_disk >= mddev->raid_disks) {
+ rdev->raid_disk = -1;
+ clear_bit(In_sync, &rdev->flags);
}
}