md:Add support for Raid0->Raid5 takeover

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 26 insertions, 0 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 10af3715b1fc..bb28fd6b44fe 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -52,6 +52,7 @@
 #include <linux/cpu.h>
 #include "md.h"
 #include "raid5.h"
+#include "raid0.h"
 #include "bitmap.h"
 
 /*
@@ -5619,6 +5620,21 @@ static void raid5_quiesce(mddev_t *mddev, int state)
 }
 
 
+static void *raid5_takeover_raid0(mddev_t *mddev)
+{
+
+        mddev->new_level = 5;
+        mddev->new_layout = ALGORITHM_PARITY_N;
+        mddev->new_chunk_sectors = mddev->chunk_sectors;
+        mddev->raid_disks += 1;
+        mddev->delta_disks = 1;
+        /* make sure it will be not marked as dirty */
+        mddev->recovery_cp = MaxSector;
+
+        return setup_conf(mddev);
+}
+
+
 static void *raid5_takeover_raid1(mddev_t *mddev)
 {
         int chunksect;
@@ -5748,6 +5764,16 @@ static void *raid5_takeover(mddev_t *mddev)
          *  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 == 1)
                 return raid5_takeover_raid1(mddev);