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 */