Add raid1->raid0 takeover support
This patch introduces raid 1 to raid0 takeover operation
in kernel space.
Signed-off-by: Krzysztof Wojcik <krzysztof.wojcik@intel.com>
Signed-off-by: Neil Brown <neilb@nbeee.brown>
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index a39f4c3..637a968 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -179,6 +179,14 @@
rdev1->new_raid_disk = j;
}
+ if (mddev->level == 1) {
+ /* taiking over a raid1 array-
+ * we have only one active disk
+ */
+ j = 0;
+ rdev1->new_raid_disk = j;
+ }
+
if (j < 0 || j >= mddev->raid_disks) {
printk(KERN_ERR "md/raid0:%s: bad disk number %d - "
"aborting!\n", mdname(mddev), j);
@@ -644,12 +652,38 @@
return priv_conf;
}
+static void *raid0_takeover_raid1(mddev_t *mddev)
+{
+ raid0_conf_t *priv_conf;
+
+ /* Check layout:
+ * - (N - 1) mirror drives must be already faulty
+ */
+ if ((mddev->raid_disks - 1) != mddev->degraded) {
+ printk(KERN_ERR "md/raid0:%s: (N - 1) mirrors drives must be already faulty!\n",
+ mdname(mddev));
+ return ERR_PTR(-EINVAL);
+ }
+
+ /* Set new parameters */
+ mddev->new_level = 0;
+ mddev->new_layout = 0;
+ mddev->new_chunk_sectors = 128; /* by default set chunk size to 64k */
+ mddev->delta_disks = 1 - mddev->raid_disks;
+ /* make sure it will be not marked as dirty */
+ mddev->recovery_cp = MaxSector;
+
+ create_strip_zones(mddev, &priv_conf);
+ return priv_conf;
+}
+
static void *raid0_takeover(mddev_t *mddev)
{
/* raid0 can take over:
* raid4 - if all data disks are active.
* raid5 - providing it is Raid4 layout and one disk is faulty
* raid10 - assuming we have all necessary active disks
+ * raid1 - with (N -1) mirror drives faulty
*/
if (mddev->level == 4)
return raid0_takeover_raid45(mddev);
@@ -665,6 +699,12 @@
if (mddev->level == 10)
return raid0_takeover_raid10(mddev);
+ if (mddev->level == 1)
+ return raid0_takeover_raid1(mddev);
+
+ printk(KERN_ERR "Takeover from raid%i to raid0 not supported\n",
+ mddev->level);
+
return ERR_PTR(-EINVAL);
}