md/raid4: permit raid0 takeover
For consistency allow raid4 to takeover raid0 in addition to raid5 (with a
raid4 layout).
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 2882a26..81563b7 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5610,10 +5610,17 @@
}
-static void *raid5_takeover_raid0(mddev_t *mddev)
+static void *raid45_takeover_raid0(mddev_t *mddev, int level)
{
+ struct raid0_private_data *raid0_priv = mddev->private;
- mddev->new_level = 5;
+ /* for raid0 takeover only one zone is supported */
+ if (raid0_priv->nr_strip_zones > 1) {
+ printk(KERN_ERR "md: cannot takeover raid0 with more than one zone.\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ mddev->new_level = level;
mddev->new_layout = ALGORITHM_PARITY_N;
mddev->new_chunk_sectors = mddev->chunk_sectors;
mddev->raid_disks += 1;
@@ -5749,22 +5756,13 @@
static void *raid5_takeover(mddev_t *mddev)
{
/* raid5 can take over:
- * raid0 - if all devices are the same - make it a raid4 layout
+ * raid0 - if there is only one strip zone - make it a raid4 layout
* raid1 - if there are two drives. We need to know the chunk size
* raid4 - trivial - just use a raid4 layout.
* raid6 - Providing it is a *_6 layout
*/
- if (mddev->level == 0) {
- /* for raid0 takeover only one zone is supported */
- struct raid0_private_data *raid0_priv
- = mddev->private;
- if (raid0_priv->nr_strip_zones > 1) {
- printk(KERN_ERR "md: cannot takeover raid 0 with more than one zone.\n");
- return ERR_PTR(-EINVAL);
- }
- return raid5_takeover_raid0(mddev);
- }
-
+ if (mddev->level == 0)
+ return raid45_takeover_raid0(mddev, 5);
if (mddev->level == 1)
return raid5_takeover_raid1(mddev);
if (mddev->level == 4) {
@@ -5780,8 +5778,12 @@
static void *raid4_takeover(mddev_t *mddev)
{
- /* raid4 can take over raid5 if layout is right.
+ /* raid4 can take over:
+ * raid0 - if there is only one strip zone
+ * raid5 - if layout is right
*/
+ if (mddev->level == 0)
+ return raid45_takeover_raid0(mddev, 4);
if (mddev->level == 5 &&
mddev->layout == ALGORITHM_PARITY_N) {
mddev->new_layout = 0;