1 files changed, 59 insertions, 10 deletions

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 787022c18187..b0ba52459ed7 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -604,7 +604,9 @@ static int read_disk_sb(struct md_rdev *rdev, int size)
 		return 0;
 
 	if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) {
-		DMERR("Failed to read device superblock");
+		DMERR("Failed to read superblock of device at position %d",
+		      rdev->raid_disk);
+		set_bit(Faulty, &rdev->flags);
 		return -EINVAL;
 	}
 
@@ -615,14 +617,14 @@ static int read_disk_sb(struct md_rdev *rdev, int size)
 
 static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
 {
-	struct md_rdev *r, *t;
+	struct md_rdev *r;
 	uint64_t failed_devices;
 	struct dm_raid_superblock *sb;
 
 	sb = page_address(rdev->sb_page);
 	failed_devices = le64_to_cpu(sb->failed_devices);
 
-	rdev_for_each(r, t, mddev)
+	rdev_for_each(r, mddev)
 		if ((r->raid_disk >= 0) && test_bit(Faulty, &r->flags))
 			failed_devices |= (1ULL << r->raid_disk);
 
@@ -707,7 +709,7 @@ static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev)
 	struct dm_raid_superblock *sb;
 	uint32_t new_devs = 0;
 	uint32_t rebuilds = 0;
-	struct md_rdev *r, *t;
+	struct md_rdev *r;
 	struct dm_raid_superblock *sb2;
 
 	sb = page_address(rdev->sb_page);
@@ -750,7 +752,7 @@ static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev)
 	 *    case the In_sync bit will /not/ be set and
 	 *    recovery_cp must be MaxSector.
 	 */
-	rdev_for_each(r, t, mddev) {
+	rdev_for_each(r, mddev) {
 		if (!test_bit(In_sync, &r->flags)) {
 			DMINFO("Device %d specified for rebuild: "
 			       "Clearing superblock", r->raid_disk);
@@ -782,7 +784,7 @@ static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev)
 	 * Now we set the Faulty bit for those devices that are
 	 * recorded in the superblock as failed.
 	 */
-	rdev_for_each(r, t, mddev) {
+	rdev_for_each(r, mddev) {
 		if (!r->sb_page)
 			continue;
 		sb2 = page_address(r->sb_page);
@@ -855,11 +857,27 @@ static int super_validate(struct mddev *mddev, struct md_rdev *rdev)
 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
 {
 	int ret;
-	struct md_rdev *rdev, *freshest, *tmp;
+	unsigned redundancy = 0;
+	struct raid_dev *dev;
+	struct md_rdev *rdev, *freshest;
 	struct mddev *mddev = &rs->md;
 
+	switch (rs->raid_type->level) {
+	case 1:
+		redundancy = rs->md.raid_disks - 1;
+		break;
+	case 4:
+	case 5:
+	case 6:
+		redundancy = rs->raid_type->parity_devs;
+		break;
+	default:
+		ti->error = "Unknown RAID type";
+		return -EINVAL;
+	}
+
 	freshest = NULL;
-	rdev_for_each(rdev, tmp, mddev) {
+	rdev_for_each(rdev, mddev) {
 		if (!rdev->meta_bdev)
 			continue;
 
@@ -872,6 +890,37 @@ static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
 		case 0:
 			break;
 		default:
+			dev = container_of(rdev, struct raid_dev, rdev);
+			if (redundancy--) {
+				if (dev->meta_dev)
+					dm_put_device(ti, dev->meta_dev);
+
+				dev->meta_dev = NULL;
+				rdev->meta_bdev = NULL;
+
+				if (rdev->sb_page)
+					put_page(rdev->sb_page);
+
+				rdev->sb_page = NULL;
+
+				rdev->sb_loaded = 0;
+
+				/*
+				 * We might be able to salvage the data device
+				 * even though the meta device has failed.  For
+				 * now, we behave as though '- -' had been
+				 * set for this device in the table.
+				 */
+				if (dev->data_dev)
+					dm_put_device(ti, dev->data_dev);
+
+				dev->data_dev = NULL;
+				rdev->bdev = NULL;
+
+				list_del(&rdev->same_set);
+
+				continue;
+			}
 			ti->error = "Failed to load superblock";
 			return ret;
 		}
@@ -888,7 +937,7 @@ static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
 	if (super_validate(mddev, freshest))
 		return -EINVAL;
 
-	rdev_for_each(rdev, tmp, mddev)
+	rdev_for_each(rdev, mddev)
 		if ((rdev != freshest) && super_validate(mddev, rdev))
 			return -EINVAL;
 
@@ -1214,7 +1263,7 @@ static void raid_resume(struct dm_target *ti)
 
 static struct target_type raid_target = {
 	.name = "raid",
-	.version = {1, 1, 0},
+	.version = {1, 2, 0},
 	.module = THIS_MODULE,
 	.ctr = raid_ctr,
 	.dtr = raid_dtr,