diff --git a/fs/dlm/config.c b/fs/dlm/config.c
index 6cf72fcc0d0..e7e327d43fa 100644
--- a/fs/dlm/config.c
+++ b/fs/dlm/config.c
@@ -2,7 +2,7 @@
 *******************************************************************************
 **
 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
-**  Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -17,6 +17,7 @@
 #include <linux/slab.h>
 #include <linux/in.h>
 #include <linux/in6.h>
+#include <linux/dlmconstants.h>
 #include <net/ipv6.h>
 #include <net/sock.h>
 
@@ -36,6 +37,7 @@
 static struct config_group *space_list;
 static struct config_group *comm_list;
 static struct dlm_comm *local_comm;
+static uint32_t dlm_comm_count;
 
 struct dlm_clusters;
 struct dlm_cluster;
@@ -103,6 +105,8 @@ struct dlm_cluster {
 	unsigned int cl_timewarn_cs;
 	unsigned int cl_waitwarn_us;
 	unsigned int cl_new_rsb_count;
+	unsigned int cl_recover_callbacks;
+	char cl_cluster_name[DLM_LOCKSPACE_LEN];
 };
 
 enum {
@@ -118,6 +122,8 @@ enum {
 	CLUSTER_ATTR_TIMEWARN_CS,
 	CLUSTER_ATTR_WAITWARN_US,
 	CLUSTER_ATTR_NEW_RSB_COUNT,
+	CLUSTER_ATTR_RECOVER_CALLBACKS,
+	CLUSTER_ATTR_CLUSTER_NAME,
 };
 
 struct cluster_attribute {
@@ -126,6 +132,27 @@ struct cluster_attribute {
 	ssize_t (*store)(struct dlm_cluster *, const char *, size_t);
 };
 
+static ssize_t cluster_cluster_name_read(struct dlm_cluster *cl, char *buf)
+{
+	return sprintf(buf, "%s\n", cl->cl_cluster_name);
+}
+
+static ssize_t cluster_cluster_name_write(struct dlm_cluster *cl,
+					  const char *buf, size_t len)
+{
+	strncpy(dlm_config.ci_cluster_name, buf, DLM_LOCKSPACE_LEN);
+	strncpy(cl->cl_cluster_name, buf, DLM_LOCKSPACE_LEN);
+	return len;
+}
+
+static struct cluster_attribute cluster_attr_cluster_name = {
+	.attr   = { .ca_owner = THIS_MODULE,
+                    .ca_name = "cluster_name",
+                    .ca_mode = S_IRUGO | S_IWUSR },
+	.show   = cluster_cluster_name_read,
+	.store  = cluster_cluster_name_write,
+};
+
 static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
 			   int *info_field, int check_zero,
 			   const char *buf, size_t len)
@@ -171,6 +198,7 @@ CLUSTER_ATTR(protocol, 0);
 CLUSTER_ATTR(timewarn_cs, 1);
 CLUSTER_ATTR(waitwarn_us, 0);
 CLUSTER_ATTR(new_rsb_count, 0);
+CLUSTER_ATTR(recover_callbacks, 0);
 
 static struct configfs_attribute *cluster_attrs[] = {
 	[CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port.attr,
@@ -185,6 +213,8 @@ static struct configfs_attribute *cluster_attrs[] = {
 	[CLUSTER_ATTR_TIMEWARN_CS] = &cluster_attr_timewarn_cs.attr,
 	[CLUSTER_ATTR_WAITWARN_US] = &cluster_attr_waitwarn_us.attr,
 	[CLUSTER_ATTR_NEW_RSB_COUNT] = &cluster_attr_new_rsb_count.attr,
+	[CLUSTER_ATTR_RECOVER_CALLBACKS] = &cluster_attr_recover_callbacks.attr,
+	[CLUSTER_ATTR_CLUSTER_NAME] = &cluster_attr_cluster_name.attr,
 	NULL,
 };
 
@@ -293,6 +323,7 @@ struct dlm_comms {
 
 struct dlm_comm {
 	struct config_item item;
+	int seq;
 	int nodeid;
 	int local;
 	int addr_count;
@@ -309,6 +340,7 @@ struct dlm_node {
 	int nodeid;
 	int weight;
 	int new;
+	int comm_seq; /* copy of cm->seq when nd->nodeid is set */
 };
 
 static struct configfs_group_operations clusters_ops = {
@@ -455,6 +487,9 @@ static struct config_group *make_cluster(struct config_group *g,
 	cl->cl_timewarn_cs = dlm_config.ci_timewarn_cs;
 	cl->cl_waitwarn_us = dlm_config.ci_waitwarn_us;
 	cl->cl_new_rsb_count = dlm_config.ci_new_rsb_count;
+	cl->cl_recover_callbacks = dlm_config.ci_recover_callbacks;
+	memcpy(cl->cl_cluster_name, dlm_config.ci_cluster_name,
+	       DLM_LOCKSPACE_LEN);
 
 	space_list = &sps->ss_group;
 	comm_list = &cms->cs_group;
@@ -558,6 +593,11 @@ static struct config_item *make_comm(struct config_group *g, const char *name)
 		return ERR_PTR(-ENOMEM);
 
 	config_item_init_type_name(&cm->item, name, &comm_type);
+
+	cm->seq = dlm_comm_count++;
+	if (!cm->seq)
+		cm->seq = dlm_comm_count++;
+
 	cm->nodeid = -1;
 	cm->local = 0;
 	cm->addr_count = 0;
@@ -801,7 +841,10 @@ static ssize_t node_nodeid_read(struct dlm_node *nd, char *buf)
 static ssize_t node_nodeid_write(struct dlm_node *nd, const char *buf,
 				 size_t len)
 {
+	uint32_t seq = 0;
 	nd->nodeid = simple_strtol(buf, NULL, 0);
+	dlm_comm_seq(nd->nodeid, &seq);
+	nd->comm_seq = seq;
 	return len;
 }
 
@@ -908,13 +951,13 @@ static void put_comm(struct dlm_comm *cm)
 }
 
 /* caller must free mem */
-int dlm_nodeid_list(char *lsname, int **ids_out, int *ids_count_out,
-		    int **new_out, int *new_count_out)
+int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
+		     int *count_out)
 {
 	struct dlm_space *sp;
 	struct dlm_node *nd;
-	int i = 0, rv = 0, ids_count = 0, new_count = 0;
-	int *ids, *new;
+	struct dlm_config_node *nodes, *node;
+	int rv, count;
 
 	sp = get_space(lsname);
 	if (!sp)
@@ -927,73 +970,42 @@ int dlm_nodeid_list(char *lsname, int **ids_out, int *ids_count_out,
 		goto out;
 	}
 
-	ids_count = sp->members_count;
+	count = sp->members_count;
 
-	ids = kcalloc(ids_count, sizeof(int), GFP_NOFS);
-	if (!ids) {
+	nodes = kcalloc(count, sizeof(struct dlm_config_node), GFP_NOFS);
+	if (!nodes) {
 		rv = -ENOMEM;
 		goto out;
 	}
 
+	node = nodes;
 	list_for_each_entry(nd, &sp->members, list) {
-		ids[i++] = nd->nodeid;
-		if (nd->new)
-			new_count++;
+		node->nodeid = nd->nodeid;
+		node->weight = nd->weight;
+		node->new = nd->new;
+		node->comm_seq = nd->comm_seq;
+		node++;
+
+		nd->new = 0;
 	}
 
-	if (ids_count != i)
-		printk(KERN_ERR "dlm: bad nodeid count %d %d\n", ids_count, i);
-
-	if (!new_count)
-		goto out_ids;
-
-	new = kcalloc(new_count, sizeof(int), GFP_NOFS);
-	if (!new) {
-		kfree(ids);
-		rv = -ENOMEM;
-		goto out;
-	}
-
-	i = 0;
-	list_for_each_entry(nd, &sp->members, list) {
-		if (nd->new) {
-			new[i++] = nd->nodeid;
-			nd->new = 0;
-		}
-	}
-	*new_count_out = new_count;
-	*new_out = new;
-
- out_ids:
-	*ids_count_out = ids_count;
-	*ids_out = ids;
+	*count_out = count;
+	*nodes_out = nodes;
+	rv = 0;
  out:
 	mutex_unlock(&sp->members_lock);
 	put_space(sp);
 	return rv;
 }
 
-int dlm_node_weight(char *lsname, int nodeid)
+int dlm_comm_seq(int nodeid, uint32_t *seq)
 {
-	struct dlm_space *sp;
-	struct dlm_node *nd;
-	int w = -EEXIST;
-
-	sp = get_space(lsname);
-	if (!sp)
-		goto out;
-
-	mutex_lock(&sp->members_lock);
-	list_for_each_entry(nd, &sp->members, list) {
-		if (nd->nodeid != nodeid)
-			continue;
-		w = nd->weight;
-		break;
-	}
-	mutex_unlock(&sp->members_lock);
-	put_space(sp);
- out:
-	return w;
+	struct dlm_comm *cm = get_comm(nodeid, NULL);
+	if (!cm)
+		return -EEXIST;
+	*seq = cm->seq;
+	put_comm(cm);
+	return 0;
 }
 
 int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr)
@@ -1047,6 +1059,8 @@ int dlm_our_addr(struct sockaddr_storage *addr, int num)
 #define DEFAULT_TIMEWARN_CS      500 /* 5 sec = 500 centiseconds */
 #define DEFAULT_WAITWARN_US	   0
 #define DEFAULT_NEW_RSB_COUNT    128
+#define DEFAULT_RECOVER_CALLBACKS  0
+#define DEFAULT_CLUSTER_NAME      ""
 
 struct dlm_config_info dlm_config = {
 	.ci_tcp_port = DEFAULT_TCP_PORT,
@@ -1060,6 +1074,8 @@ struct dlm_config_info dlm_config = {
 	.ci_protocol = DEFAULT_PROTOCOL,
 	.ci_timewarn_cs = DEFAULT_TIMEWARN_CS,
 	.ci_waitwarn_us = DEFAULT_WAITWARN_US,
-	.ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT
+	.ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT,
+	.ci_recover_callbacks = DEFAULT_RECOVER_CALLBACKS,
+	.ci_cluster_name = DEFAULT_CLUSTER_NAME
 };
 
diff --git a/fs/dlm/config.h b/fs/dlm/config.h
index 3099d0dd26c..9f5e3663bb0 100644
--- a/fs/dlm/config.h
+++ b/fs/dlm/config.h
@@ -2,7 +2,7 @@
 *******************************************************************************
 **
 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
-**  Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -14,6 +14,13 @@
 #ifndef __CONFIG_DOT_H__
 #define __CONFIG_DOT_H__
 
+struct dlm_config_node {
+	int nodeid;
+	int weight;
+	int new;
+	uint32_t comm_seq;
+};
+
 #define DLM_MAX_ADDR_COUNT 3
 
 struct dlm_config_info {
@@ -29,15 +36,17 @@ struct dlm_config_info {
 	int ci_timewarn_cs;
 	int ci_waitwarn_us;
 	int ci_new_rsb_count;
+	int ci_recover_callbacks;
+	char ci_cluster_name[DLM_LOCKSPACE_LEN];
 };
 
 extern struct dlm_config_info dlm_config;
 
 int dlm_config_init(void);
 void dlm_config_exit(void);
-int dlm_node_weight(char *lsname, int nodeid);
-int dlm_nodeid_list(char *lsname, int **ids_out, int *ids_count_out,
-		    int **new_out, int *new_count_out);
+int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
+		     int *count_out);
+int dlm_comm_seq(int nodeid, uint32_t *seq);
 int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr);
 int dlm_addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid);
 int dlm_our_nodeid(void);
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index f4d132c7690..3a564d197e9 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -2,7 +2,7 @@
 *******************************************************************************
 **
 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
-**  Copyright (C) 2004-2010 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -119,28 +119,18 @@ struct dlm_member {
 	int			weight;
 	int			slot;
 	int			slot_prev;
+	int			comm_seq;
 	uint32_t		generation;
 };
 
-/*
- * low nodeid saves array of these in ls_slots
- */
-
-struct dlm_slot {
-	int			nodeid;
-	int			slot;
-};
-
 /*
  * Save and manage recovery state for a lockspace.
  */
 
 struct dlm_recover {
 	struct list_head	list;
-	int			*nodeids;   /* nodeids of all members */
-	int			node_count;
-	int			*new;       /* nodeids of new members */
-	int			new_count;
+	struct dlm_config_node	*nodes;
+	int			nodes_count;
 	uint64_t		seq;
 };
 
@@ -584,6 +574,9 @@ struct dlm_ls {
 	struct list_head	ls_root_list;	/* root resources */
 	struct rw_semaphore	ls_root_sem;	/* protect root_list */
 
+	const struct dlm_lockspace_ops *ls_ops;
+	void			*ls_ops_arg;
+
 	int			ls_namelen;
 	char			ls_name[1];
 };
diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index 1441f04bfab..a1ea25face8 100644
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -2,7 +2,7 @@
 *******************************************************************************
 **
 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
-**  Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -386,12 +386,15 @@ static void threads_stop(void)
 	dlm_lowcomms_stop();
 }
 
-static int new_lockspace(const char *name, int namelen, void **lockspace,
-			 uint32_t flags, int lvblen)
+static int new_lockspace(const char *name, const char *cluster,
+			 uint32_t flags, int lvblen,
+			 const struct dlm_lockspace_ops *ops, void *ops_arg,
+			 int *ops_result, dlm_lockspace_t **lockspace)
 {
 	struct dlm_ls *ls;
 	int i, size, error;
 	int do_unreg = 0;
+	int namelen = strlen(name);
 
 	if (namelen > DLM_LOCKSPACE_LEN)
 		return -EINVAL;
@@ -403,8 +406,24 @@ static int new_lockspace(const char *name, int namelen, void **lockspace,
 		return -EINVAL;
 
 	if (!dlm_user_daemon_available()) {
-		module_put(THIS_MODULE);
-		return -EUNATCH;
+		log_print("dlm user daemon not available");
+		error = -EUNATCH;
+		goto out;
+	}
+
+	if (ops && ops_result) {
+	       	if (!dlm_config.ci_recover_callbacks)
+			*ops_result = -EOPNOTSUPP;
+		else
+			*ops_result = 0;
+	}
+
+	if (dlm_config.ci_recover_callbacks && cluster &&
+	    strncmp(cluster, dlm_config.ci_cluster_name, DLM_LOCKSPACE_LEN)) {
+		log_print("dlm cluster name %s mismatch %s",
+			  dlm_config.ci_cluster_name, cluster);
+		error = -EBADR;
+		goto out;
 	}
 
 	error = 0;
@@ -442,6 +461,11 @@ static int new_lockspace(const char *name, int namelen, void **lockspace,
 	ls->ls_flags = 0;
 	ls->ls_scan_time = jiffies;
 
+	if (ops && dlm_config.ci_recover_callbacks) {
+		ls->ls_ops = ops;
+		ls->ls_ops_arg = ops_arg;
+	}
+
 	if (flags & DLM_LSFL_TIMEWARN)
 		set_bit(LSFL_TIMEWARN, &ls->ls_flags);
 
@@ -619,8 +643,10 @@ static int new_lockspace(const char *name, int namelen, void **lockspace,
 	return error;
 }
 
-int dlm_new_lockspace(const char *name, int namelen, void **lockspace,
-		      uint32_t flags, int lvblen)
+int dlm_new_lockspace(const char *name, const char *cluster,
+		      uint32_t flags, int lvblen,
+		      const struct dlm_lockspace_ops *ops, void *ops_arg,
+		      int *ops_result, dlm_lockspace_t **lockspace)
 {
 	int error = 0;
 
@@ -630,7 +656,8 @@ int dlm_new_lockspace(const char *name, int namelen, void **lockspace,
 	if (error)
 		goto out;
 
-	error = new_lockspace(name, namelen, lockspace, flags, lvblen);
+	error = new_lockspace(name, cluster, flags, lvblen, ops, ops_arg,
+			      ops_result, lockspace);
 	if (!error)
 		ls_count++;
 	if (error > 0)
diff --git a/fs/dlm/member.c b/fs/dlm/member.c
index eebc52aae82..862640a36d5 100644
--- a/fs/dlm/member.c
+++ b/fs/dlm/member.c
@@ -1,7 +1,7 @@
 /******************************************************************************
 *******************************************************************************
 **
-**  Copyright (C) 2005-2009 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2005-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -27,7 +27,7 @@ int dlm_slots_version(struct dlm_header *h)
 }
 
 void dlm_slot_save(struct dlm_ls *ls, struct dlm_rcom *rc,
-		  struct dlm_member *memb)
+		   struct dlm_member *memb)
 {
 	struct rcom_config *rf = (struct rcom_config *)rc->rc_buf;
 
@@ -317,59 +317,51 @@ static void add_ordered_member(struct dlm_ls *ls, struct dlm_member *new)
 	}
 }
 
-static int dlm_add_member(struct dlm_ls *ls, int nodeid)
+static int dlm_add_member(struct dlm_ls *ls, struct dlm_config_node *node)
 {
 	struct dlm_member *memb;
-	int w, error;
+	int error;
 
 	memb = kzalloc(sizeof(struct dlm_member), GFP_NOFS);
 	if (!memb)
 		return -ENOMEM;
 
-	w = dlm_node_weight(ls->ls_name, nodeid);
-	if (w < 0) {
-		kfree(memb);
-		return w;
-	}
-
-	error = dlm_lowcomms_connect_node(nodeid);
+	error = dlm_lowcomms_connect_node(node->nodeid);
 	if (error < 0) {
 		kfree(memb);
 		return error;
 	}
 
-	memb->nodeid = nodeid;
-	memb->weight = w;
+	memb->nodeid = node->nodeid;
+	memb->weight = node->weight;
+	memb->comm_seq = node->comm_seq;
 	add_ordered_member(ls, memb);
 	ls->ls_num_nodes++;
 	return 0;
 }
 
-static void dlm_remove_member(struct dlm_ls *ls, struct dlm_member *memb)
+static struct dlm_member *find_memb(struct list_head *head, int nodeid)
 {
-	list_move(&memb->list, &ls->ls_nodes_gone);
-	ls->ls_num_nodes--;
+	struct dlm_member *memb;
+
+	list_for_each_entry(memb, head, list) {
+		if (memb->nodeid == nodeid)
+			return memb;
+	}
+	return NULL;
 }
 
 int dlm_is_member(struct dlm_ls *ls, int nodeid)
 {
-	struct dlm_member *memb;
-
-	list_for_each_entry(memb, &ls->ls_nodes, list) {
-		if (memb->nodeid == nodeid)
-			return 1;
-	}
+	if (find_memb(&ls->ls_nodes, nodeid))
+		return 1;
 	return 0;
 }
 
 int dlm_is_removed(struct dlm_ls *ls, int nodeid)
 {
-	struct dlm_member *memb;
-
-	list_for_each_entry(memb, &ls->ls_nodes_gone, list) {
-		if (memb->nodeid == nodeid)
-			return 1;
-	}
+	if (find_memb(&ls->ls_nodes_gone, nodeid))
+		return 1;
 	return 0;
 }
 
@@ -460,10 +452,88 @@ static int ping_members(struct dlm_ls *ls)
 	return error;
 }
 
+static void dlm_lsop_recover_prep(struct dlm_ls *ls)
+{
+	if (!ls->ls_ops || !ls->ls_ops->recover_prep)
+		return;
+	ls->ls_ops->recover_prep(ls->ls_ops_arg);
+}
+
+static void dlm_lsop_recover_slot(struct dlm_ls *ls, struct dlm_member *memb)
+{
+	struct dlm_slot slot;
+	uint32_t seq;
+	int error;
+
+	if (!ls->ls_ops || !ls->ls_ops->recover_slot)
+		return;
+
+	/* if there is no comms connection with this node
+	   or the present comms connection is newer
+	   than the one when this member was added, then
+	   we consider the node to have failed (versus
+	   being removed due to dlm_release_lockspace) */
+
+	error = dlm_comm_seq(memb->nodeid, &seq);
+
+	if (!error && seq == memb->comm_seq)
+		return;
+
+	slot.nodeid = memb->nodeid;
+	slot.slot = memb->slot;
+
+	ls->ls_ops->recover_slot(ls->ls_ops_arg, &slot);
+}
+
+void dlm_lsop_recover_done(struct dlm_ls *ls)
+{
+	struct dlm_member *memb;
+	struct dlm_slot *slots;
+	int i, num;
+
+	if (!ls->ls_ops || !ls->ls_ops->recover_done)
+		return;
+
+	num = ls->ls_num_nodes;
+
+	slots = kzalloc(num * sizeof(struct dlm_slot), GFP_KERNEL);
+	if (!slots)
+		return;
+
+	i = 0;
+	list_for_each_entry(memb, &ls->ls_nodes, list) {
+		if (i == num) {
+			log_error(ls, "dlm_lsop_recover_done bad num %d", num);
+			goto out;
+		}
+		slots[i].nodeid = memb->nodeid;
+		slots[i].slot = memb->slot;
+		i++;
+	}
+
+	ls->ls_ops->recover_done(ls->ls_ops_arg, slots, num,
+				 ls->ls_slot, ls->ls_generation);
+ out:
+	kfree(slots);
+}
+
+static struct dlm_config_node *find_config_node(struct dlm_recover *rv,
+						int nodeid)
+{
+	int i;
+
+	for (i = 0; i < rv->nodes_count; i++) {
+		if (rv->nodes[i].nodeid == nodeid)
+			return &rv->nodes[i];
+	}
+	return NULL;
+}
+
 int dlm_recover_members(struct dlm_ls *ls, struct dlm_recover *rv, int *neg_out)
 {
 	struct dlm_member *memb, *safe;
-	int i, error, found, pos = 0, neg = 0, low = -1;
+	struct dlm_config_node *node;
+	int i, error, neg = 0, low = -1;
 
 	/* previously removed members that we've not finished removing need to
 	   count as a negative change so the "neg" recovery steps will happen */
@@ -476,46 +546,32 @@ int dlm_recover_members(struct dlm_ls *ls, struct dlm_recover *rv, int *neg_out)
 	/* move departed members from ls_nodes to ls_nodes_gone */
 
 	list_for_each_entry_safe(memb, safe, &ls->ls_nodes, list) {
-		found = 0;
-		for (i = 0; i < rv->node_count; i++) {
-			if (memb->nodeid == rv->nodeids[i]) {
-				found = 1;
-				break;
-			}
-		}
-
-		if (!found) {
-			neg++;
-			dlm_remove_member(ls, memb);
-			log_debug(ls, "remove member %d", memb->nodeid);
-		}
-	}
-
-	/* Add an entry to ls_nodes_gone for members that were removed and
-	   then added again, so that previous state for these nodes will be
-	   cleared during recovery. */
-
-	for (i = 0; i < rv->new_count; i++) {
-		if (!dlm_is_member(ls, rv->new[i]))
+		node = find_config_node(rv, memb->nodeid);
+		if (node && !node->new)
 			continue;
-		log_debug(ls, "new nodeid %d is a re-added member", rv->new[i]);
 
-		memb = kzalloc(sizeof(struct dlm_member), GFP_NOFS);
-		if (!memb)
-			return -ENOMEM;
-		memb->nodeid = rv->new[i];
-		list_add_tail(&memb->list, &ls->ls_nodes_gone);
+		if (!node) {
+			log_debug(ls, "remove member %d", memb->nodeid);
+		} else {
+			/* removed and re-added */
+			log_debug(ls, "remove member %d comm_seq %u %u",
+				  memb->nodeid, memb->comm_seq, node->comm_seq);
+		}
+
 		neg++;
+		list_move(&memb->list, &ls->ls_nodes_gone);
+		ls->ls_num_nodes--;
+		dlm_lsop_recover_slot(ls, memb);
 	}
 
 	/* add new members to ls_nodes */
 
-	for (i = 0; i < rv->node_count; i++) {
-		if (dlm_is_member(ls, rv->nodeids[i]))
+	for (i = 0; i < rv->nodes_count; i++) {
+		node = &rv->nodes[i];
+		if (dlm_is_member(ls, node->nodeid))
 			continue;
-		dlm_add_member(ls, rv->nodeids[i]);
-		pos++;
-		log_debug(ls, "add member %d", rv->nodeids[i]);
+		dlm_add_member(ls, node);
+		log_debug(ls, "add member %d", node->nodeid);
 	}
 
 	list_for_each_entry(memb, &ls->ls_nodes, list) {
@@ -609,21 +665,22 @@ int dlm_ls_stop(struct dlm_ls *ls)
 
 	if (!ls->ls_recover_begin)
 		ls->ls_recover_begin = jiffies;
+
+	dlm_lsop_recover_prep(ls);
 	return 0;
 }
 
 int dlm_ls_start(struct dlm_ls *ls)
 {
 	struct dlm_recover *rv = NULL, *rv_old;
-	int *ids = NULL, *new = NULL;
-	int error, ids_count = 0, new_count = 0;
+	struct dlm_config_node *nodes;
+	int error, count;
 
 	rv = kzalloc(sizeof(struct dlm_recover), GFP_NOFS);
 	if (!rv)
 		return -ENOMEM;
 
-	error = dlm_nodeid_list(ls->ls_name, &ids, &ids_count,
-				&new, &new_count);
+	error = dlm_config_nodes(ls->ls_name, &nodes, &count);
 	if (error < 0)
 		goto fail;
 
@@ -638,10 +695,8 @@ int dlm_ls_start(struct dlm_ls *ls)
 		goto fail;
 	}
 
-	rv->nodeids = ids;
-	rv->node_count = ids_count;
-	rv->new = new;
-	rv->new_count = new_count;
+	rv->nodes = nodes;
+	rv->nodes_count = count;
 	rv->seq = ++ls->ls_recover_seq;
 	rv_old = ls->ls_recover_args;
 	ls->ls_recover_args = rv;
@@ -649,9 +704,8 @@ int dlm_ls_start(struct dlm_ls *ls)
 
 	if (rv_old) {
 		log_error(ls, "unused recovery %llx %d",
-			  (unsigned long long)rv_old->seq, rv_old->node_count);
-		kfree(rv_old->nodeids);
-		kfree(rv_old->new);
+			  (unsigned long long)rv_old->seq, rv_old->nodes_count);
+		kfree(rv_old->nodes);
 		kfree(rv_old);
 	}
 
@@ -660,8 +714,7 @@ int dlm_ls_start(struct dlm_ls *ls)
 
  fail:
 	kfree(rv);
-	kfree(ids);
-	kfree(new);
+	kfree(nodes);
 	return error;
 }
 
diff --git a/fs/dlm/member.h b/fs/dlm/member.h
index 7e87e8a79df..3deb70661c6 100644
--- a/fs/dlm/member.h
+++ b/fs/dlm/member.h
@@ -1,7 +1,7 @@
 /******************************************************************************
 *******************************************************************************
 **
-**  Copyright (C) 2005-2008 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2005-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -27,6 +27,7 @@ void dlm_slots_copy_out(struct dlm_ls *ls, struct dlm_rcom *rc);
 int dlm_slots_copy_in(struct dlm_ls *ls);
 int dlm_slots_assign(struct dlm_ls *ls, int *num_slots, int *slots_size,
 		     struct dlm_slot **slots_out, uint32_t *gen_out);
+void dlm_lsop_recover_done(struct dlm_ls *ls);
 
 #endif                          /* __MEMBER_DOT_H__ */
 
diff --git a/fs/dlm/recoverd.c b/fs/dlm/recoverd.c
index 5a9e1a49a86..3780caf7ae0 100644
--- a/fs/dlm/recoverd.c
+++ b/fs/dlm/recoverd.c
@@ -2,7 +2,7 @@
 *******************************************************************************
 **
 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
-**  Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -227,11 +227,12 @@ static int ls_recover(struct dlm_ls *ls, struct dlm_recover *rv)
 
 	dlm_grant_after_purge(ls);
 
-	log_debug(ls, "dlm_recover %llx done: %u ms",
-		  (unsigned long long)rv->seq,
+	log_debug(ls, "dlm_recover %llx generation %u done: %u ms",
+		  (unsigned long long)rv->seq, ls->ls_generation,
 		  jiffies_to_msecs(jiffies - start));
 	mutex_unlock(&ls->ls_recoverd_active);
 
+	dlm_lsop_recover_done(ls);
 	return 0;
 
  fail:
@@ -259,8 +260,7 @@ static void do_ls_recovery(struct dlm_ls *ls)
 
 	if (rv) {
 		ls_recover(ls, rv);
-		kfree(rv->nodeids);
-		kfree(rv->new);
+		kfree(rv->nodes);
 		kfree(rv);
 	}
 }
diff --git a/fs/dlm/user.c b/fs/dlm/user.c
index d8ea6075640..eb4ed9ba309 100644
--- a/fs/dlm/user.c
+++ b/fs/dlm/user.c
@@ -392,8 +392,9 @@ static int device_create_lockspace(struct dlm_lspace_params *params)
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
-	error = dlm_new_lockspace(params->name, strlen(params->name),
-				  &lockspace, params->flags, DLM_USER_LVB_LEN);
+	error = dlm_new_lockspace(params->name, NULL, params->flags,
+				  DLM_USER_LVB_LEN, NULL, NULL, NULL,
+				  &lockspace);
 	if (error)
 		return error;
 
diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c
index 98c80d8c2a6..ce85b62bc0a 100644
--- a/fs/gfs2/lock_dlm.c
+++ b/fs/gfs2/lock_dlm.c
@@ -195,10 +195,10 @@ static int gdlm_mount(struct gfs2_sbd *sdp, const char *fsname)
 		return -EINVAL;
 	}
 
-	error = dlm_new_lockspace(fsname, strlen(fsname), &ls->ls_dlm,
+	error = dlm_new_lockspace(fsname, NULL, 
 				  DLM_LSFL_FS | DLM_LSFL_NEWEXCL |
 				  (ls->ls_nodir ? DLM_LSFL_NODIR : 0),
-				  GDLM_LVB_SIZE);
+				  GDLM_LVB_SIZE, NULL, NULL, NULL, &ls->ls_dlm);
 	if (error)
 		printk(KERN_ERR "dlm_new_lockspace error %d", error);
 
diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
index a5ebe421195..286edf1e231 100644
--- a/fs/ocfs2/stack_user.c
+++ b/fs/ocfs2/stack_user.c
@@ -827,8 +827,8 @@ static int user_cluster_connect(struct ocfs2_cluster_connection *conn)
 		goto out;
 	}
 
-	rc = dlm_new_lockspace(conn->cc_name, strlen(conn->cc_name),
-			       &fsdlm, DLM_LSFL_FS, DLM_LVB_LEN);
+	rc = dlm_new_lockspace(conn->cc_name, NULL, DLM_LSFL_FS, DLM_LVB_LEN,
+			       NULL, NULL, NULL, &fsdlm);
 	if (rc) {
 		ocfs2_live_connection_drop(control);
 		goto out;
diff --git a/include/linux/dlm.h b/include/linux/dlm.h
index d4e02f5353a..6c7f6e9546c 100644
--- a/include/linux/dlm.h
+++ b/include/linux/dlm.h
@@ -2,7 +2,7 @@
 *******************************************************************************
 **
 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
-**  Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -74,15 +74,76 @@ struct dlm_lksb {
 
 #ifdef __KERNEL__
 
+struct dlm_slot {
+	int nodeid; /* 1 to MAX_INT */
+	int slot;   /* 1 to MAX_INT */
+};
+
+/*
+ * recover_prep: called before the dlm begins lock recovery.
+ *   Notfies lockspace user that locks from failed members will be granted.
+ * recover_slot: called after recover_prep and before recover_done.
+ *   Identifies a failed lockspace member.
+ * recover_done: called after the dlm completes lock recovery.
+ *   Identifies lockspace members and lockspace generation number.
+ */
+
+struct dlm_lockspace_ops {
+	void (*recover_prep) (void *ops_arg);
+	void (*recover_slot) (void *ops_arg, struct dlm_slot *slot);
+	void (*recover_done) (void *ops_arg, struct dlm_slot *slots,
+			      int num_slots, int our_slot, uint32_t generation);
+};
+
 /*
  * dlm_new_lockspace
  *
- * Starts a lockspace with the given name.  If the named lockspace exists in
- * the cluster, the calling node joins it.
+ * Create/join a lockspace.
+ *
+ * name: lockspace name, null terminated, up to DLM_LOCKSPACE_LEN (not
+ *   including terminating null).
+ *
+ * cluster: cluster name, null terminated, up to DLM_LOCKSPACE_LEN (not
+ *   including terminating null).  Optional.  When cluster is null, it
+ *   is not used.  When set, dlm_new_lockspace() returns -EBADR if cluster
+ *   is not equal to the dlm cluster name.
+ *
+ * flags:
+ * DLM_LSFL_NODIR
+ *   The dlm should not use a resource directory, but statically assign
+ *   resource mastery to nodes based on the name hash that is otherwise
+ *   used to select the directory node.  Must be the same on all nodes.
+ * DLM_LSFL_TIMEWARN
+ *   The dlm should emit netlink messages if locks have been waiting
+ *   for a configurable amount of time.  (Unused.)
+ * DLM_LSFL_FS
+ *   The lockspace user is in the kernel (i.e. filesystem).  Enables
+ *   direct bast/cast callbacks.
+ * DLM_LSFL_NEWEXCL
+ *   dlm_new_lockspace() should return -EEXIST if the lockspace exists.
+ *
+ * lvblen: length of lvb in bytes.  Must be multiple of 8.
+ *   dlm_new_lockspace() returns an error if this does not match
+ *   what other nodes are using.
+ *
+ * ops: callbacks that indicate lockspace recovery points so the
+ *   caller can coordinate its recovery and know lockspace members.
+ *   This is only used by the initial dlm_new_lockspace() call.
+ *   Optional.
+ *
+ * ops_arg: arg for ops callbacks.
+ *
+ * ops_result: tells caller if the ops callbacks (if provided) will
+ *   be used or not.  0: will be used, -EXXX will not be used.
+ *   -EOPNOTSUPP: the dlm does not have recovery_callbacks enabled.
+ *
+ * lockspace: handle for dlm functions
  */
 
-int dlm_new_lockspace(const char *name, int namelen,
-		      dlm_lockspace_t **lockspace, uint32_t flags, int lvblen);
+int dlm_new_lockspace(const char *name, const char *cluster,
+		      uint32_t flags, int lvblen,
+		      const struct dlm_lockspace_ops *ops, void *ops_arg,
+		      int *ops_result, dlm_lockspace_t **lockspace);
 
 /*
  * dlm_release_lockspace