6 files changed, 64 insertions, 9 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index e2aacca46911..b43a75a246e7 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -637,6 +637,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
 	if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN)
 		set_bit(BITMAP_HOSTENDIAN, &bitmap->flags);
 	bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
+	strlcpy(bitmap->mddev->bitmap_info.cluster_name, sb->cluster_name, 64);
 	err = 0;
 out:
 	kunmap_atomic(sb);
diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
index f4e53eadb083..ec9032f105b8 100644
--- a/drivers/md/bitmap.h
+++ b/drivers/md/bitmap.h
@@ -130,9 +130,9 @@ typedef struct bitmap_super_s {
 	__le32 write_behind; /* 60  number of outstanding write-behind writes */
 	__le32 sectors_reserved; /* 64 number of 512-byte sectors that are
 				  * reserved for the bitmap. */
-
 	__le32 nodes;        /* 68 the maximum number of nodes in cluster. */
-	__u8  pad[256 - 72]; /* set to zero */
+	__u8 cluster_name[64]; /* 72 cluster name to which this md belongs */
+	__u8  pad[256 - 136]; /* set to zero */
 } bitmap_super_t;
 
 /* notes:
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index d141d4812c8c..1f3c8f39ecb2 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -30,6 +30,8 @@ struct dlm_lock_resource {
 struct md_cluster_info {
 	/* dlm lock space and resources for clustered raid. */
 	dlm_lockspace_t *lockspace;
+	int slot_number;
+	struct completion completion;
 	struct dlm_lock_resource *sb_lock;
 	struct mutex sb_mutex;
 };
@@ -136,10 +138,42 @@ static char *pretty_uuid(char *dest, char *src)
 	return dest;
 }
 
+static void recover_prep(void *arg)
+{
+}
+
+static void recover_slot(void *arg, struct dlm_slot *slot)
+{
+	struct mddev *mddev = arg;
+	struct md_cluster_info *cinfo = mddev->cluster_info;
+
+	pr_info("md-cluster: %s Node %d/%d down. My slot: %d. Initiating recovery.\n",
+			mddev->bitmap_info.cluster_name,
+			slot->nodeid, slot->slot,
+			cinfo->slot_number);
+}
+
+static void recover_done(void *arg, struct dlm_slot *slots,
+		int num_slots, int our_slot,
+		uint32_t generation)
+{
+	struct mddev *mddev = arg;
+	struct md_cluster_info *cinfo = mddev->cluster_info;
+
+	cinfo->slot_number = our_slot;
+	complete(&cinfo->completion);
+}
+
+static const struct dlm_lockspace_ops md_ls_ops = {
+	.recover_prep = recover_prep,
+	.recover_slot = recover_slot,
+	.recover_done = recover_done,
+};
+
 static int join(struct mddev *mddev, int nodes)
 {
 	struct md_cluster_info *cinfo;
-	int ret;
+	int ret, ops_rv;
 	char str[64];
 
 	if (!try_module_get(THIS_MODULE))
@@ -149,24 +183,30 @@ static int join(struct mddev *mddev, int nodes)
 	if (!cinfo)
 		return -ENOMEM;
 
+	init_completion(&cinfo->completion);
+
+	mutex_init(&cinfo->sb_mutex);
+	mddev->cluster_info = cinfo;
+
 	memset(str, 0, 64);
 	pretty_uuid(str, mddev->uuid);
-	ret = dlm_new_lockspace(str, NULL, DLM_LSFL_FS, LVB_SIZE,
-				NULL, NULL, NULL, &cinfo->lockspace);
+	ret = dlm_new_lockspace(str, mddev->bitmap_info.cluster_name,
+				DLM_LSFL_FS, LVB_SIZE,
+				&md_ls_ops, mddev, &ops_rv, &cinfo->lockspace);
 	if (ret)
 		goto err;
+	wait_for_completion(&cinfo->completion);
 	cinfo->sb_lock = lockres_init(mddev, "cmd-super",
 					NULL, 0);
 	if (!cinfo->sb_lock) {
 		ret = -ENOMEM;
 		goto err;
 	}
-	mutex_init(&cinfo->sb_mutex);
-	mddev->cluster_info = cinfo;
 	return 0;
 err:
 	if (cinfo->lockspace)
 		dlm_release_lockspace(cinfo->lockspace, 2);
+	mddev->cluster_info = NULL;
 	kfree(cinfo);
 	module_put(THIS_MODULE);
 	return ret;
@@ -183,9 +223,21 @@ static int leave(struct mddev *mddev)
 	return 0;
 }
 
+/* slot_number(): Returns the MD slot number to use
+ * DLM starts the slot numbers from 1, wheras cluster-md
+ * wants the number to be from zero, so we deduct one
+ */
+static int slot_number(struct mddev *mddev)
+{
+	struct md_cluster_info *cinfo = mddev->cluster_info;
+
+	return cinfo->slot_number - 1;
+}
+
 static struct md_cluster_operations cluster_ops = {
 	.join   = join,
 	.leave  = leave,
+	.slot_number = slot_number,
 };
 
 static int __init cluster_init(void)
diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h
index aa9f07bd6b96..52a21e0d6dbc 100644
--- a/drivers/md/md-cluster.h
+++ b/drivers/md/md-cluster.h
@@ -8,8 +8,9 @@
 struct mddev;
 
 struct md_cluster_operations {
-	int (*join)(struct mddev *mddev);
+	int (*join)(struct mddev *mddev, int nodes);
 	int (*leave)(struct mddev *mddev);
+	int (*slot_number)(struct mddev *mddev);
 };
 
 #endif /* _MD_CLUSTER_H */
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 5ed57688e5c5..8f310d98f082 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -7277,7 +7277,7 @@ int md_setup_cluster(struct mddev *mddev, int nodes)
 	}
 	spin_unlock(&pers_lock);
 
-	return md_cluster_ops->join(mddev);
+	return md_cluster_ops->join(mddev, nodes);
 }
 
 void md_cluster_stop(struct mddev *mddev)
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 80fc89976915..81e568090d8f 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -434,6 +434,7 @@ struct mddev {
 		unsigned long		max_write_behind; /* write-behind mode */
 		int			external;
 		int			nodes; /* Maximum number of nodes in the cluster */
+		char                    cluster_name[64]; /* Name of the cluster */
 	} bitmap_info;
 
 	atomic_t			max_corr_read_errors; /* max read retries */