Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

10 files changed, 1270 insertions, 283 deletions

diff --git a/fs/ocfs2/dlm/Makefile b/fs/ocfs2/dlm/Makefile
index ce3f7c29d27..19036137570 100644
--- a/fs/ocfs2/dlm/Makefile
+++ b/fs/ocfs2/dlm/Makefile
@@ -1,6 +1,6 @@
 EXTRA_CFLAGS += -Ifs/ocfs2
 
-obj-$(CONFIG_OCFS2_FS) += ocfs2_dlm.o ocfs2_dlmfs.o
+obj-$(CONFIG_OCFS2_FS_O2CB) += ocfs2_dlm.o ocfs2_dlmfs.o
 
 ocfs2_dlm-objs := dlmdomain.o dlmdebug.o dlmthread.o dlmrecovery.o \
 	dlmmaster.o dlmast.o dlmconvert.o dlmlock.o dlmunlock.o dlmver.o
diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h
index 9843ee17ea2..d5a86fb81a4 100644
--- a/fs/ocfs2/dlm/dlmcommon.h
+++ b/fs/ocfs2/dlm/dlmcommon.h
@@ -49,6 +49,41 @@
 /* Intended to make it easier for us to switch out hash functions */
 #define dlm_lockid_hash(_n, _l) full_name_hash(_n, _l)
 
+enum dlm_mle_type {
+	DLM_MLE_BLOCK,
+	DLM_MLE_MASTER,
+	DLM_MLE_MIGRATION
+};
+
+struct dlm_lock_name {
+	u8 len;
+	u8 name[DLM_LOCKID_NAME_MAX];
+};
+
+struct dlm_master_list_entry {
+	struct list_head list;
+	struct list_head hb_events;
+	struct dlm_ctxt *dlm;
+	spinlock_t spinlock;
+	wait_queue_head_t wq;
+	atomic_t woken;
+	struct kref mle_refs;
+	int inuse;
+	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+	u8 master;
+	u8 new_master;
+	enum dlm_mle_type type;
+	struct o2hb_callback_func mle_hb_up;
+	struct o2hb_callback_func mle_hb_down;
+	union {
+		struct dlm_lock_resource *res;
+		struct dlm_lock_name name;
+	} u;
+};
+
 enum dlm_ast_type {
 	DLM_AST = 0,
 	DLM_BAST,
@@ -101,6 +136,7 @@ struct dlm_ctxt
 	struct list_head purge_list;
 	struct list_head pending_asts;
 	struct list_head pending_basts;
+	struct list_head tracking_list;
 	unsigned int purge_count;
 	spinlock_t spinlock;
 	spinlock_t ast_lock;
@@ -122,6 +158,9 @@ struct dlm_ctxt
 	atomic_t remote_resources;
 	atomic_t unknown_resources;
 
+	struct dlm_debug_ctxt *dlm_debug_ctxt;
+	struct dentry *dlm_debugfs_subroot;
+
 	/* NOTE: Next three are protected by dlm_domain_lock */
 	struct kref dlm_refs;
 	enum dlm_ctxt_state dlm_state;
@@ -176,6 +215,7 @@ struct dlm_mig_lockres_priv
 {
 	struct dlm_lock_resource *lockres;
 	u8 real_master;
+	u8 extra_ref;
 };
 
 struct dlm_assert_master_priv
@@ -269,6 +309,9 @@ struct dlm_lock_resource
 	struct list_head dirty;
 	struct list_head recovering; // dlm_recovery_ctxt.resources list
 
+	/* Added during init and removed during release */
+	struct list_head tracking;	/* dlm->tracking_list */
+
 	/* unused lock resources have their last_used stamped and are
 	 * put on a list for the dlm thread to run. */
 	unsigned long    last_used;
@@ -602,17 +645,19 @@ enum dlm_query_join_response_code {
 	JOIN_PROTOCOL_MISMATCH,
 };
 
+struct dlm_query_join_packet {
+	u8 code;	/* Response code.  dlm_minor and fs_minor
+			   are only valid if this is JOIN_OK */
+	u8 dlm_minor;	/* The minor version of the protocol the
+			   dlm is speaking. */
+	u8 fs_minor;	/* The minor version of the protocol the
+			   filesystem is speaking. */
+	u8 reserved;
+};
+
 union dlm_query_join_response {
 	u32 intval;
-	struct {
-		u8 code;	/* Response code.  dlm_minor and fs_minor
-				   are only valid if this is JOIN_OK */
-		u8 dlm_minor;	/* The minor version of the protocol the
-				   dlm is speaking. */
-		u8 fs_minor;	/* The minor version of the protocol the
-				   filesystem is speaking. */
-		u8 reserved;
-	} packet;
+	struct dlm_query_join_packet packet;
 };
 
 struct dlm_lock_request
@@ -960,9 +1005,16 @@ static inline void __dlm_wait_on_lockres(struct dlm_lock_resource *res)
 					  DLM_LOCK_RES_MIGRATING));
 }
 
+/* create/destroy slab caches */
+int dlm_init_master_caches(void);
+void dlm_destroy_master_caches(void);
+
+int dlm_init_lock_cache(void);
+void dlm_destroy_lock_cache(void);
 
 int dlm_init_mle_cache(void);
 void dlm_destroy_mle_cache(void);
+
 void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up);
 int dlm_drop_lockres_ref(struct dlm_ctxt *dlm,
 			 struct dlm_lock_resource *res);
diff --git a/fs/ocfs2/dlm/dlmconvert.c b/fs/ocfs2/dlm/dlmconvert.c
index ecb4d997221..75997b4deaf 100644
--- a/fs/ocfs2/dlm/dlmconvert.c
+++ b/fs/ocfs2/dlm/dlmconvert.c
@@ -487,7 +487,7 @@ int dlm_convert_lock_handler(struct o2net_msg *msg, u32 len, void *data,
 			       "cookie=%u:%llu\n",
 		     dlm_get_lock_cookie_node(be64_to_cpu(cnv->cookie)),
 		     dlm_get_lock_cookie_seq(be64_to_cpu(cnv->cookie)));
-		__dlm_print_one_lock_resource(res);
+		dlm_print_one_lock_resource(res);
 		goto leave;
 	}
 
diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c
index 64239b37e5d..5f6d858770a 100644
--- a/fs/ocfs2/dlm/dlmdebug.c
+++ b/fs/ocfs2/dlm/dlmdebug.c
@@ -5,7 +5,7 @@
  *
  * debug functionality for the dlm
  *
- * Copyright (C) 2004 Oracle.  All rights reserved.
+ * Copyright (C) 2004, 2008 Oracle.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public
@@ -30,6 +30,7 @@
 #include <linux/utsname.h>
 #include <linux/sysctl.h>
 #include <linux/spinlock.h>
+#include <linux/debugfs.h>
 
 #include "cluster/heartbeat.h"
 #include "cluster/nodemanager.h"
@@ -37,17 +38,16 @@
 
 #include "dlmapi.h"
 #include "dlmcommon.h"
-
 #include "dlmdomain.h"
+#include "dlmdebug.h"
 
 #define MLOG_MASK_PREFIX ML_DLM
 #include "cluster/masklog.h"
 
+int stringify_lockname(const char *lockname, int locklen, char *buf, int len);
+
 void dlm_print_one_lock_resource(struct dlm_lock_resource *res)
 {
-	mlog(ML_NOTICE, "lockres: %.*s, owner=%u, state=%u\n",
-	       res->lockname.len, res->lockname.name,
-	       res->owner, res->state);
 	spin_lock(&res->spinlock);
 	__dlm_print_one_lock_resource(res);
 	spin_unlock(&res->spinlock);
@@ -58,7 +58,7 @@ static void dlm_print_lockres_refmap(struct dlm_lock_resource *res)
 	int bit;
 	assert_spin_locked(&res->spinlock);
 
-	mlog(ML_NOTICE, "  refmap nodes: [ ");
+	printk("  refmap nodes: [ ");
 	bit = 0;
 	while (1) {
 		bit = find_next_bit(res->refmap, O2NM_MAX_NODES, bit);
@@ -70,63 +70,66 @@ static void dlm_print_lockres_refmap(struct dlm_lock_resource *res)
 	printk("], inflight=%u\n", res->inflight_locks);
 }
 
+static void __dlm_print_lock(struct dlm_lock *lock)
+{
+	spin_lock(&lock->spinlock);
+
+	printk("    type=%d, conv=%d, node=%u, cookie=%u:%llu, "
+	       "ref=%u, ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c), "
+	       "pending=(conv=%c,lock=%c,cancel=%c,unlock=%c)\n",
+	       lock->ml.type, lock->ml.convert_type, lock->ml.node,
+	       dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
+	       dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
+	       atomic_read(&lock->lock_refs.refcount),
+	       (list_empty(&lock->ast_list) ? 'y' : 'n'),
+	       (lock->ast_pending ? 'y' : 'n'),
+	       (list_empty(&lock->bast_list) ? 'y' : 'n'),
+	       (lock->bast_pending ? 'y' : 'n'),
+	       (lock->convert_pending ? 'y' : 'n'),
+	       (lock->lock_pending ? 'y' : 'n'),
+	       (lock->cancel_pending ? 'y' : 'n'),
+	       (lock->unlock_pending ? 'y' : 'n'));
+
+	spin_unlock(&lock->spinlock);
+}
+
 void __dlm_print_one_lock_resource(struct dlm_lock_resource *res)
 {
 	struct list_head *iter2;
 	struct dlm_lock *lock;
+	char buf[DLM_LOCKID_NAME_MAX];
 
 	assert_spin_locked(&res->spinlock);
 
-	mlog(ML_NOTICE, "lockres: %.*s, owner=%u, state=%u\n",
-	       res->lockname.len, res->lockname.name,
-	       res->owner, res->state);
-	mlog(ML_NOTICE, "  last used: %lu, on purge list: %s\n",
-	     res->last_used, list_empty(&res->purge) ? "no" : "yes");
+	stringify_lockname(res->lockname.name, res->lockname.len,
+			   buf, sizeof(buf) - 1);
+	printk("lockres: %s, owner=%u, state=%u\n",
+	       buf, res->owner, res->state);
+	printk("  last used: %lu, refcnt: %u, on purge list: %s\n",
+	       res->last_used, atomic_read(&res->refs.refcount),
+	       list_empty(&res->purge) ? "no" : "yes");
+	printk("  on dirty list: %s, on reco list: %s, "
+	       "migrating pending: %s\n",
+	       list_empty(&res->dirty) ? "no" : "yes",
+	       list_empty(&res->recovering) ? "no" : "yes",
+	       res->migration_pending ? "yes" : "no");
+	printk("  inflight locks: %d, asts reserved: %d\n",
+	       res->inflight_locks, atomic_read(&res->asts_reserved));
 	dlm_print_lockres_refmap(res);
-	mlog(ML_NOTICE, "  granted queue: \n");
+	printk("  granted queue:\n");
 	list_for_each(iter2, &res->granted) {
 		lock = list_entry(iter2, struct dlm_lock, list);
-		spin_lock(&lock->spinlock);
-		mlog(ML_NOTICE, "    type=%d, conv=%d, node=%u, "
-		       "cookie=%u:%llu, ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c)\n", 
-		       lock->ml.type, lock->ml.convert_type, lock->ml.node, 
-		     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
-		     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
-		       list_empty(&lock->ast_list) ? 'y' : 'n',
-		       lock->ast_pending ? 'y' : 'n',
-		       list_empty(&lock->bast_list) ? 'y' : 'n',
-		       lock->bast_pending ? 'y' : 'n');
-		spin_unlock(&lock->spinlock);
+		__dlm_print_lock(lock);
 	}
-	mlog(ML_NOTICE, "  converting queue: \n");
+	printk("  converting queue:\n");
 	list_for_each(iter2, &res->converting) {
 		lock = list_entry(iter2, struct dlm_lock, list);
-		spin_lock(&lock->spinlock);
-		mlog(ML_NOTICE, "    type=%d, conv=%d, node=%u, "
-		       "cookie=%u:%llu, ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c)\n", 
-		       lock->ml.type, lock->ml.convert_type, lock->ml.node, 
-		     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
-		     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
-		       list_empty(&lock->ast_list) ? 'y' : 'n',
-		       lock->ast_pending ? 'y' : 'n',
-		       list_empty(&lock->bast_list) ? 'y' : 'n',
-		       lock->bast_pending ? 'y' : 'n');
-		spin_unlock(&lock->spinlock);
+		__dlm_print_lock(lock);
 	}
-	mlog(ML_NOTICE, "  blocked queue: \n");
+	printk("  blocked queue:\n");
 	list_for_each(iter2, &res->blocked) {
 		lock = list_entry(iter2, struct dlm_lock, list);
-		spin_lock(&lock->spinlock);
-		mlog(ML_NOTICE, "    type=%d, conv=%d, node=%u, "
-		       "cookie=%u:%llu, ast=(empty=%c,pend=%c), bast=(empty=%c,pend=%c)\n", 
-		       lock->ml.type, lock->ml.convert_type, lock->ml.node, 
-		     dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
-		     dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
-		       list_empty(&lock->ast_list) ? 'y' : 'n',
-		       lock->ast_pending ? 'y' : 'n',
-		       list_empty(&lock->bast_list) ? 'y' : 'n',
-		       lock->bast_pending ? 'y' : 'n');
-		spin_unlock(&lock->spinlock);
+		__dlm_print_lock(lock);
 	}
 }
 
@@ -136,31 +139,6 @@ void dlm_print_one_lock(struct dlm_lock *lockid)
 }
 EXPORT_SYMBOL_GPL(dlm_print_one_lock);
 
-#if 0
-void dlm_dump_lock_resources(struct dlm_ctxt *dlm)
-{
-	struct dlm_lock_resource *res;
-	struct hlist_node *iter;
-	struct hlist_head *bucket;
-	int i;
-
-	mlog(ML_NOTICE, "struct dlm_ctxt: %s, node=%u, key=%u\n",
-		  dlm->name, dlm->node_num, dlm->key);
-	if (!dlm || !dlm->name) {
-		mlog(ML_ERROR, "dlm=%p\n", dlm);
-		return;
-	}
-
-	spin_lock(&dlm->spinlock);
-	for (i=0; i<DLM_HASH_BUCKETS; i++) {
-		bucket = dlm_lockres_hash(dlm, i);
-		hlist_for_each_entry(res, iter, bucket, hash_node)
-			dlm_print_one_lock_resource(res);
-	}
-	spin_unlock(&dlm->spinlock);
-}
-#endif  /*  0  */
-
 static const char *dlm_errnames[] = {
 	[DLM_NORMAL] =			"DLM_NORMAL",
 	[DLM_GRANTED] =			"DLM_GRANTED",
@@ -266,3 +244,792 @@ const char *dlm_errname(enum dlm_status err)
 	return dlm_errnames[err];
 }
 EXPORT_SYMBOL_GPL(dlm_errname);
+
+/* NOTE: This function converts a lockname into a string. It uses knowledge
+ * of the format of the lockname that should be outside the purview of the dlm.
+ * We are adding only to make dlm debugging slightly easier.
+ *
+ * For more on lockname formats, please refer to dlmglue.c and ocfs2_lockid.h.
+ */
+int stringify_lockname(const char *lockname, int locklen, char *buf, int len)
+{
+	int out = 0;
+	__be64 inode_blkno_be;
+
+#define OCFS2_DENTRY_LOCK_INO_START	18
+	if (*lockname == 'N') {
+		memcpy((__be64 *)&inode_blkno_be,
+		       (char *)&lockname[OCFS2_DENTRY_LOCK_INO_START],
+		       sizeof(__be64));
+		out += snprintf(buf + out, len - out, "%.*s%08x",
+				OCFS2_DENTRY_LOCK_INO_START - 1, lockname,
+				(unsigned int)be64_to_cpu(inode_blkno_be));
+	} else
+		out += snprintf(buf + out, len - out, "%.*s",
+				locklen, lockname);
+	return out;
+}
+
+static int stringify_nodemap(unsigned long *nodemap, int maxnodes,
+			     char *buf, int len)
+{
+	int out = 0;
+	int i = -1;
+
+	while ((i = find_next_bit(nodemap, maxnodes, i + 1)) < maxnodes)
+		out += snprintf(buf + out, len - out, "%d ", i);
+
+	return out;
+}
+
+static int dump_mle(struct dlm_master_list_entry *mle, char *buf, int len)
+{
+	int out = 0;
+	unsigned int namelen;
+	const char *name;
+	char *mle_type;
+
+	if (mle->type != DLM_MLE_MASTER) {
+		namelen = mle->u.name.len;
+		name = mle->u.name.name;
+	} else {
+		namelen = mle->u.res->lockname.len;
+		name = mle->u.res->lockname.name;
+	}
+
+	if (mle->type == DLM_MLE_BLOCK)
+		mle_type = "BLK";
+	else if (mle->type == DLM_MLE_MASTER)
+		mle_type = "MAS";
+	else
+		mle_type = "MIG";
+
+	out += stringify_lockname(name, namelen, buf + out, len - out);
+	out += snprintf(buf + out, len - out,
+			"\t%3s\tmas=%3u\tnew=%3u\tevt=%1d\tuse=%1d\tref=%3d\n",
+			mle_type, mle->master, mle->new_master,
+			!list_empty(&mle->hb_events),
+			!!mle->inuse,
+			atomic_read(&mle->mle_refs.refcount));
+
+	out += snprintf(buf + out, len - out, "Maybe=");
+	out += stringify_nodemap(mle->maybe_map, O2NM_MAX_NODES,
+				 buf + out, len - out);
+	out += snprintf(buf + out, len - out, "\n");
+
+	out += snprintf(buf + out, len - out, "Vote=");
+	out += stringify_nodemap(mle->vote_map, O2NM_MAX_NODES,
+				 buf + out, len - out);
+	out += snprintf(buf + out, len - out, "\n");
+
+	out += snprintf(buf + out, len - out, "Response=");
+	out += stringify_nodemap(mle->response_map, O2NM_MAX_NODES,
+				 buf + out, len - out);
+	out += snprintf(buf + out, len - out, "\n");
+
+	out += snprintf(buf + out, len - out, "Node=");
+	out += stringify_nodemap(mle->node_map, O2NM_MAX_NODES,
+				 buf + out, len - out);
+	out += snprintf(buf + out, len - out, "\n");
+
+	out += snprintf(buf + out, len - out, "\n");
+
+	return out;
+}
+
+void dlm_print_one_mle(struct dlm_master_list_entry *mle)
+{
+	char *buf;
+
+	buf = (char *) get_zeroed_page(GFP_NOFS);
+	if (buf) {
+		dump_mle(mle, buf, PAGE_SIZE - 1);
+		free_page((unsigned long)buf);
+	}
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+static struct dentry *dlm_debugfs_root = NULL;
+
+#define DLM_DEBUGFS_DIR				"o2dlm"
+#define DLM_DEBUGFS_DLM_STATE			"dlm_state"
+#define DLM_DEBUGFS_LOCKING_STATE		"locking_state"
+#define DLM_DEBUGFS_MLE_STATE			"mle_state"
+#define DLM_DEBUGFS_PURGE_LIST			"purge_list"
+
+/* begin - utils funcs */
+static void dlm_debug_free(struct kref *kref)
+{
+	struct dlm_debug_ctxt *dc;
+
+	dc = container_of(kref, struct dlm_debug_ctxt, debug_refcnt);
+
+	kfree(dc);
+}
+
+void dlm_debug_put(struct dlm_debug_ctxt *dc)
+{
+	if (dc)
+		kref_put(&dc->debug_refcnt, dlm_debug_free);
+}
+
+static void dlm_debug_get(struct dlm_debug_ctxt *dc)
+{
+	kref_get(&dc->debug_refcnt);
+}
+
+static struct debug_buffer *debug_buffer_allocate(void)
+{
+	struct debug_buffer *db = NULL;
+
+	db = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
+	if (!db)
+		goto bail;
+
+	db->len = PAGE_SIZE;
+	db->buf = kmalloc(db->len, GFP_KERNEL);
+	if (!db->buf)
+		goto bail;
+
+	return db;
+bail:
+	kfree(db);
+	return NULL;
+}
+
+static ssize_t debug_buffer_read(struct file *file, char __user *buf,
+				 size_t nbytes, loff_t *ppos)
+{
+	struct debug_buffer *db = file->private_data;
+
+	return simple_read_from_buffer(buf, nbytes, ppos, db->buf, db->len);
+}
+
+static loff_t debug_buffer_llseek(struct file *file, loff_t off, int whence)
+{
+	struct debug_buffer *db = file->private_data;
+	loff_t new = -1;
+
+	switch (whence) {
+	case 0:
+		new = off;
+		break;
+	case 1:
+		new = file->f_pos + off;
+		break;
+	}
+
+	if (new < 0 || new > db->len)
+		return -EINVAL;
+
+	return (file->f_pos = new);
+}
+
+static int debug_buffer_release(struct inode *inode, struct file *file)
+{
+	struct debug_buffer *db = (struct debug_buffer *)file->private_data;
+
+	if (db)
+		kfree(db->buf);
+	kfree(db);
+
+	return 0;
+}
+/* end - util funcs */
+
+/* begin - purge list funcs */
+static int debug_purgelist_print(struct dlm_ctxt *dlm, struct debug_buffer *db)
+{
+	struct dlm_lock_resource *res;
+	int out = 0;
+	unsigned long total = 0;
+
+	out += snprintf(db->buf + out, db->len - out,
+			"Dumping Purgelist for Domain: %s\n", dlm->name);
+
+	spin_lock(&dlm->spinlock);
+	list_for_each_entry(res, &dlm->purge_list, purge) {
+		++total;
+		if (db->len - out < 100)
+			continue;
+		spin_lock(&res->spinlock);
+		out += stringify_lockname(res->lockname.name,
+					  res->lockname.len,
+					  db->buf + out, db->len - out);
+		out += snprintf(db->buf + out, db->len - out, "\t%ld\n",
+				(jiffies - res->last_used)/HZ);
+		spin_unlock(&res->spinlock);
+	}
+	spin_unlock(&dlm->spinlock);
+
+	out += snprintf(db->buf + out, db->len - out,
+			"Total on list: %ld\n", total);
+
+	return out;
+}
+
+static int debug_purgelist_open(struct inode *inode, struct file *file)
+{
+	struct dlm_ctxt *dlm = inode->i_private;
+	struct debug_buffer *db;
+
+	db = debug_buffer_allocate();
+	if (!db)
+		goto bail;
+
+	db->len = debug_purgelist_print(dlm, db);
+
+	file->private_data = db;
+
+	return 0;
+bail:
+	return -ENOMEM;
+}
+
+static struct file_operations debug_purgelist_fops = {
+	.open =		debug_purgelist_open,
+	.release =	debug_buffer_release,
+	.read =		debug_buffer_read,
+	.llseek =	debug_buffer_llseek,
+};
+/* end - purge list funcs */
+
+/* begin - debug mle funcs */
+static int debug_mle_print(struct dlm_ctxt *dlm, struct debug_buffer *db)
+{
+	struct dlm_master_list_entry *mle;
+	int out = 0;
+	unsigned long total = 0;
+
+	out += snprintf(db->buf + out, db->len - out,
+			"Dumping MLEs for Domain: %s\n", dlm->name);
+
+	spin_lock(&dlm->master_lock);
+	list_for_each_entry(mle, &dlm->master_list, list) {
+		++total;
+		if (db->len - out < 200)
+			continue;
+		out += dump_mle(mle, db->buf + out, db->len - out);
+	}
+	spin_unlock(&dlm->master_lock);
+
+	out += snprintf(db->buf + out, db->len - out,
+			"Total on list: %ld\n", total);
+	return out;
+}
+
+static int debug_mle_open(struct inode *inode, struct file *file)
+{
+	struct dlm_ctxt *dlm = inode->i_private;
+	struct debug_buffer *db;
+
+	db = debug_buffer_allocate();
+	if (!db)
+		goto bail;
+
+	db->len = debug_mle_print(dlm, db);
+
+	file->private_data = db;
+
+	return 0;
+bail:
+	return -ENOMEM;
+}
+
+static struct file_operations debug_mle_fops = {
+	.open =		debug_mle_open,
+	.release =	debug_buffer_release,
+	.read =		debug_buffer_read,
+	.llseek =	debug_buffer_llseek,
+};
+
+/* end - debug mle funcs */
+
+/* begin - debug lockres funcs */
+static int dump_lock(struct dlm_lock *lock, int list_type, char *buf, int len)
+{
+	int out;
+
+#define DEBUG_LOCK_VERSION	1
+	spin_lock(&lock->spinlock);
+	out = snprintf(buf, len, "LOCK:%d,%d,%d,%d,%d,%d:%lld,%d,%d,%d,%d,%d,"
+		       "%d,%d,%d,%d\n",
+		       DEBUG_LOCK_VERSION,
+		       list_type, lock->ml.type, lock->ml.convert_type,
+		       lock->ml.node,
+		       dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)),
+		       dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)),
+		       !list_empty(&lock->ast_list),
+		       !list_empty(&lock->bast_list),
+		       lock->ast_pending, lock->bast_pending,
+		       lock->convert_pending, lock->lock_pending,
+		       lock->cancel_pending, lock->unlock_pending,
+		       atomic_read(&lock->lock_refs.refcount));
+	spin_unlock(&lock->spinlock);
+
+	return out;
+}
+
+static int dump_lockres(struct dlm_lock_resource *res, char *buf, int len)
+{
+	struct dlm_lock *lock;
+	int i;
+	int out = 0;
+
+	out += snprintf(buf + out, len - out, "NAME:");
+	out += stringify_lockname(res->lockname.name, res->lockname.len,
+				  buf + out, len - out);
+	out += snprintf(buf + out, len - out, "\n");
+
+#define DEBUG_LRES_VERSION	1
+	out += snprintf(buf + out, len - out,
+			"LRES:%d,%d,%d,%ld,%d,%d,%d,%d,%d,%d,%d\n",
+			DEBUG_LRES_VERSION,
+			res->owner, res->state, res->last_used,
+			!list_empty(&res->purge),
+			!list_empty(&res->dirty),
+			!list_empty(&res->recovering),
+			res->inflight_locks, res->migration_pending,
+			atomic_read(&res->asts_reserved),
+			atomic_read(&res->refs.refcount));
+
+	/* refmap */
+	out += snprintf(buf + out, len - out, "RMAP:");
+	out += stringify_nodemap(res->refmap, O2NM_MAX_NODES,
+				 buf + out, len - out);
+	out += snprintf(buf + out, len - out, "\n");
+
+	/* lvb */
+	out += snprintf(buf + out, len - out, "LVBX:");
+	for (i = 0; i < DLM_LVB_LEN; i++)
+		out += snprintf(buf + out, len - out,
+					"%02x", (unsigned char)res->lvb[i]);
+	out += snprintf(buf + out, len - out, "\n");
+
+	/* granted */
+	list_for_each_entry(lock, &res->granted, list)
+		out += dump_lock(lock, 0, buf + out, len - out);
+
+	/* converting */
+	list_for_each_entry(lock, &res->converting, list)
+		out += dump_lock(lock, 1, buf + out, len - out);
+
+	/* blocked */
+	list_for_each_entry(lock, &res->blocked, list)
+		out += dump_lock(lock, 2, buf + out, len - out);
+
+	out += snprintf(buf + out, len - out, "\n");
+
+	return out;
+}
+
+static void *lockres_seq_start(struct seq_file *m, loff_t *pos)
+{
+	struct debug_lockres *dl = m->private;
+	struct dlm_ctxt *dlm = dl->dl_ctxt;
+	struct dlm_lock_resource *res = NULL;
+
+	spin_lock(&dlm->spinlock);
+
+	if (dl->dl_res) {
+		list_for_each_entry(res, &dl->dl_res->tracking, tracking) {
+			if (dl->dl_res) {
+				dlm_lockres_put(dl->dl_res);
+				dl->dl_res = NULL;
+			}
+			if (&res->tracking == &dlm->tracking_list) {
+				mlog(0, "End of list found, %p\n", res);
+				dl = NULL;
+				break;
+			}
+			dlm_lockres_get(res);
+			dl->dl_res = res;
+			break;
+		}
+	} else {
+		if (!list_empty(&dlm->tracking_list)) {
+			list_for_each_entry(res, &dlm->tracking_list, tracking)
+				break;
+			dlm_lockres_get(res);
+			dl->dl_res = res;
+		} else
+			dl = NULL;
+	}
+
+	if (dl) {
+		spin_lock(&dl->dl_res->spinlock);
+		dump_lockres(dl->dl_res, dl->dl_buf, dl->dl_len - 1);
+		spin_unlock(&dl->dl_res->spinlock);
+	}
+
+	spin_unlock(&dlm->spinlock);
+
+	return dl;
+}
+
+static void lockres_seq_stop(struct seq_file *m, void *v)
+{
+}
+
+static void *lockres_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	return NULL;
+}
+
+static int lockres_seq_show(struct seq_file *s, void *v)
+{
+	struct debug_lockres *dl = (struct debug_lockres *)v;
+
+	seq_printf(s, "%s", dl->dl_buf);
+
+	return 0;
+}
+
+static struct seq_operations debug_lockres_ops = {
+	.start =	lockres_seq_start,
+	.stop =		lockres_seq_stop,
+	.next =		lockres_seq_next,
+	.show =		lockres_seq_show,
+};
+
+static int debug_lockres_open(struct inode *inode, struct file *file)
+{
+	struct dlm_ctxt *dlm = inode->i_private;
+	int ret = -ENOMEM;
+	struct seq_file *seq;
+	struct debug_lockres *dl = NULL;
+
+	dl = kzalloc(sizeof(struct debug_lockres), GFP_KERNEL);
+	if (!dl) {
+		mlog_errno(ret);
+		goto bail;
+	}
+
+	dl->dl_len = PAGE_SIZE;
+	dl->dl_buf = kmalloc(dl->dl_len, GFP_KERNEL);
+	if (!dl->dl_buf) {
+		mlog_errno(ret);
+		goto bail;
+	}
+
+	ret = seq_open(file, &debug_lockres_ops);
+	if (ret) {
+		mlog_errno(ret);
+		goto bail;
+	}
+
+	seq = (struct seq_file *) file->private_data;
+	seq->private = dl;
+
+	dlm_grab(dlm);
+	dl->dl_ctxt = dlm;
+
+	return 0;
+bail:
+	if (dl)
+		kfree(dl->dl_buf);
+	kfree(dl);
+	return ret;
+}
+
+static int debug_lockres_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq = (struct seq_file *)file->private_data;
+	struct debug_lockres *dl = (struct debug_lockres *)seq->private;
+
+	if (dl->dl_res)
+		dlm_lockres_put(dl->dl_res);
+	dlm_put(dl->dl_ctxt);
+	kfree(dl->dl_buf);
+	return seq_release_private(inode, file);
+}
+
+static struct file_operations debug_lockres_fops = {
+	.open =		debug_lockres_open,
+	.release =	debug_lockres_release,
+	.read =		seq_read,
+	.llseek =	seq_lseek,
+};
+/* end - debug lockres funcs */
+
+/* begin - debug state funcs */
+static int debug_state_print(struct dlm_ctxt *dlm, struct debug_buffer *db)
+{
+	int out = 0;
+	struct dlm_reco_node_data *node;
+	char *state;
+	int lres, rres, ures, tres;
+
+	lres = atomic_read(&dlm->local_resources);
+	rres = atomic_read(&dlm->remote_resources);
+	ures = atomic_read(&dlm->unknown_resources);
+	tres = lres + rres + ures;
+
+	spin_lock(&dlm->spinlock);
+
+	switch (dlm->dlm_state) {
+	case DLM_CTXT_NEW:
+		state = "NEW"; break;
+	case DLM_CTXT_JOINED:
+		state = "JOINED"; break;
+	case DLM_CTXT_IN_SHUTDOWN:
+		state = "SHUTDOWN"; break;
+	case DLM_CTXT_LEAVING:
+		state = "LEAVING"; break;
+	default:
+		state = "UNKNOWN"; break;
+	}
+
+	/* Domain: xxxxxxxxxx  Key: 0xdfbac769 */
+	out += snprintf(db->buf + out, db->len - out,
+			"Domain: %s  Key: 0x%08x\n", dlm->name, dlm->key);
+
+	/* Thread Pid: xxx  Node: xxx  State: xxxxx */
+	out += snprintf(db->buf + out, db->len - out,
+			"Thread Pid: %d  Node: %d  State: %s\n",
+			dlm->dlm_thread_task->pid, dlm->node_num, state);
+
+	/* Number of Joins: xxx  Joining Node: xxx */
+	out += snprintf(db->buf + out, db->len - out,
+			"Number of Joins: %d  Joining Node: %d\n",
+			dlm->num_joins, dlm->joining_node);
+
+	/* Domain Map: xx xx xx */
+	out += snprintf(db->buf + out, db->len - out, "Domain Map: ");
+	out += stringify_nodemap(dlm->domain_map, O2NM_MAX_NODES,
+				 db->buf + out, db->len - out);
+	out += snprintf(db->buf + out, db->len - out, "\n");
+
+	/* Live Map: xx xx xx */
+	out += snprintf(db->buf + out, db->len - out, "Live Map: ");
+	out += stringify_nodemap(dlm->live_nodes_map, O2NM_MAX_NODES,
+				 db->buf + out, db->len - out);
+	out += snprintf(db->buf + out, db->len - out, "\n");
+
+	/* Mastered Resources Total: xxx  Locally: xxx  Remotely: ... */
+	out += snprintf(db->buf + out, db->len - out,
+			"Mastered Resources Total: %d  Locally: %d  "
+			"Remotely: %d  Unknown: %d\n",
+			tres, lres, rres, ures);
+
+	/* Lists: Dirty=Empty  Purge=InUse  PendingASTs=Empty  ... */
+	out += snprintf(db->buf + out, db->len - out,
+			"Lists: Dirty=%s  Purge=%s  PendingASTs=%s  "
+			"PendingBASTs=%s  Master=%s\n",
+			(list_empty(&dlm->dirty_list) ? "Empty" : "InUse"),
+			(list_empty(&dlm->purge_list) ? "Empty" : "InUse"),
+			(list_empty(&dlm->pending_asts) ? "Empty" : "InUse"),
+			(list_empty(&dlm->pending_basts) ? "Empty" : "InUse"),
+			(list_empty(&dlm->master_list) ? "Empty" : "InUse"));
+
+	/* Purge Count: xxx  Refs: xxx */
+	out += snprintf(db->buf + out, db->len - out,
+			"Purge Count: %d  Refs: %d\n", dlm->purge_count,
+			atomic_read(&dlm->dlm_refs.refcount));
+
+	/* Dead Node: xxx */
+	out += snprintf(db->buf + out, db->len - out,
+			"Dead Node: %d\n", dlm->reco.dead_node);
+
+	/* What about DLM_RECO_STATE_FINALIZE? */
+	if (dlm->reco.state == DLM_RECO_STATE_ACTIVE)
+		state = "ACTIVE";
+	else
+		state = "INACTIVE";
+
+	/* Recovery Pid: xxxx  Master: xxx  State: xxxx */
+	out += snprintf(db->buf + out, db->len - out,
+			"Recovery Pid: %d  Master: %d  State: %s\n",
+			dlm->dlm_reco_thread_task->pid,
+			dlm->reco.new_master, state);
+
+	/* Recovery Map: xx xx */
+	out += snprintf(db->buf + out, db->len - out, "Recovery Map: ");
+	out += stringify_nodemap(dlm->recovery_map, O2NM_MAX_NODES,
+				 db->buf + out, db->len - out);
+	out += snprintf(db->buf + out, db->len - out, "\n");
+
+	/* Recovery Node State: */
+	out += snprintf(db->buf + out, db->len - out, "Recovery Node State:\n");
+	list_for_each_entry(node, &dlm->reco.node_data, list) {
+		switch (node->state) {
+		case DLM_RECO_NODE_DATA_INIT:
+			state = "INIT";
+			break;
+		case DLM_RECO_NODE_DATA_REQUESTING:
+			state = "REQUESTING";
+			break;
+		case DLM_RECO_NODE_DATA_DEAD:
+			state = "DEAD";
+			break;
+		case DLM_RECO_NODE_DATA_RECEIVING:
+			state = "RECEIVING";
+			break;
+		case DLM_RECO_NODE_DATA_REQUESTED:
+			state = "REQUESTED";
+			break;
+		case DLM_RECO_NODE_DATA_DONE:
+			state = "DONE";
+			break;
+		case DLM_RECO_NODE_DATA_FINALIZE_SENT:
+			state = "FINALIZE-SENT";
+			break;
+		default:
+			state = "BAD";
+			break;
+		}
+		out += snprintf(db->buf + out, db->len - out, "\t%u - %s\n",
+				node->node_num, state);
+	}
+
+	spin_unlock(&dlm->spinlock);
+
+	return out;
+}
+
+static int debug_state_open(struct inode *inode, struct file *file)
+{
+	struct dlm_ctxt *dlm = inode->i_private;
+	struct debug_buffer *db = NULL;
+
+	db = debug_buffer_allocate();
+	if (!db)
+		goto bail;
+
+	db->len = debug_state_print(dlm, db);
+
+	file->private_data = db;
+
+	return 0;
+bail:
+	return -ENOMEM;
+}
+
+static struct file_operations debug_state_fops = {
+	.open =		debug_state_open,
+	.release =	debug_buffer_release,
+	.read =		debug_buffer_read,
+	.llseek =	debug_buffer_llseek,
+};
+/* end  - debug state funcs */
+
+/* files in subroot */
+int dlm_debug_init(struct dlm_ctxt *dlm)
+{
+	struct dlm_debug_ctxt *dc = dlm->dlm_debug_ctxt;
+
+	/* for dumping dlm_ctxt */
+	dc->debug_state_dentry = debugfs_create_file(DLM_DEBUGFS_DLM_STATE,
+						     S_IFREG|S_IRUSR,
+						     dlm->dlm_debugfs_subroot,
+						     dlm, &debug_state_fops);
+	if (!dc->debug_state_dentry) {
+		mlog_errno(-ENOMEM);
+		goto bail;
+	}
+
+	/* for dumping lockres */
+	dc->debug_lockres_dentry =
+			debugfs_create_file(DLM_DEBUGFS_LOCKING_STATE,
+					    S_IFREG|S_IRUSR,
+					    dlm->dlm_debugfs_subroot,
+					    dlm, &debug_lockres_fops);
+	if (!dc->debug_lockres_dentry) {
+		mlog_errno(-ENOMEM);
+		goto bail;
+	}
+
+	/* for dumping mles */
+	dc->debug_mle_dentry = debugfs_create_file(DLM_DEBUGFS_MLE_STATE,
+						   S_IFREG|S_IRUSR,
+						   dlm->dlm_debugfs_subroot,
+						   dlm, &debug_mle_fops);
+	if (!dc->debug_mle_dentry) {
+		mlog_errno(-ENOMEM);
+		goto bail;
+	}
+
+	/* for dumping lockres on the purge list */
+	dc->debug_purgelist_dentry =
+			debugfs_create_file(DLM_DEBUGFS_PURGE_LIST,
+					    S_IFREG|S_IRUSR,
+					    dlm->dlm_debugfs_subroot,
+					    dlm, &debug_purgelist_fops);
+	if (!dc->debug_purgelist_dentry) {
+		mlog_errno(-ENOMEM);
+		goto bail;
+	}
+
+	dlm_debug_get(dc);
+	return 0;
+
+bail:
+	dlm_debug_shutdown(dlm);
+	return -ENOMEM;
+}
+
+void dlm_debug_shutdown(struct dlm_ctxt *dlm)
+{
+	struct dlm_debug_ctxt *dc = dlm->dlm_debug_ctxt;
+
+	if (dc) {
+		if (dc->debug_purgelist_dentry)
+			debugfs_remove(dc->debug_purgelist_dentry);
+		if (dc->debug_mle_dentry)
+			debugfs_remove(dc->debug_mle_dentry);
+		if (dc->debug_lockres_dentry)
+			debugfs_remove(dc->debug_lockres_dentry);
+		if (dc->debug_state_dentry)
+			debugfs_remove(dc->debug_state_dentry);
+		dlm_debug_put(dc);
+	}
+}
+
+/* subroot - domain dir */
+int dlm_create_debugfs_subroot(struct dlm_ctxt *dlm)
+{
+	dlm->dlm_debugfs_subroot = debugfs_create_dir(dlm->name,
+						      dlm_debugfs_root);
+	if (!dlm->dlm_debugfs_subroot) {
+		mlog_errno(-ENOMEM);
+		goto bail;
+	}
+
+	dlm->dlm_debug_ctxt = kzalloc(sizeof(struct dlm_debug_ctxt),
+				      GFP_KERNEL);
+	if (!dlm->dlm_debug_ctxt) {
+		mlog_errno(-ENOMEM);
+		goto bail;
+	}
+	kref_init(&dlm->dlm_debug_ctxt->debug_refcnt);
+
+	return 0;
+bail:
+	dlm_destroy_debugfs_subroot(dlm);
+	return -ENOMEM;
+}
+
+void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm)
+{
+	if (dlm->dlm_debugfs_subroot)
+		debugfs_remove(dlm->dlm_debugfs_subroot);
+}
+
+/* debugfs root */
+int dlm_create_debugfs_root(void)
+{
+	dlm_debugfs_root = debugfs_create_dir(DLM_DEBUGFS_DIR, NULL);
+	if (!dlm_debugfs_root) {
+		mlog_errno(-ENOMEM);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+void dlm_destroy_debugfs_root(void)
+{
+	if (dlm_debugfs_root)
+		debugfs_remove(dlm_debugfs_root);
+}
+#endif	/* CONFIG_DEBUG_FS */
diff --git a/fs/ocfs2/dlm/dlmdebug.h b/fs/ocfs2/dlm/dlmdebug.h
new file mode 100644
index 00000000000..d34a62a3a62
--- /dev/null
+++ b/fs/ocfs2/dlm/dlmdebug.h
@@ -0,0 +1,86 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * dlmdebug.h
+ *
+ * Copyright (C) 2008 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ *
+ */
+
+#ifndef DLMDEBUG_H
+#define DLMDEBUG_H
+
+void dlm_print_one_mle(struct dlm_master_list_entry *mle);
+
+#ifdef CONFIG_DEBUG_FS
+
+struct dlm_debug_ctxt {
+	struct kref debug_refcnt;
+	struct dentry *debug_state_dentry;
+	struct dentry *debug_lockres_dentry;
+	struct dentry *debug_mle_dentry;
+	struct dentry *debug_purgelist_dentry;
+};
+
+struct debug_buffer {
+	int len;
+	char *buf;
+};
+
+struct debug_lockres {
+	int dl_len;
+	char *dl_buf;
+	struct dlm_ctxt *dl_ctxt;
+	struct dlm_lock_resource *dl_res;
+};
+
+int dlm_debug_init(struct dlm_ctxt *dlm);
+void dlm_debug_shutdown(struct dlm_ctxt *dlm);
+
+int dlm_create_debugfs_subroot(struct dlm_ctxt *dlm);
+void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm);
+
+int dlm_create_debugfs_root(void);
+void dlm_destroy_debugfs_root(void);
+
+#else
+
+static int dlm_debug_init(struct dlm_ctxt *dlm)
+{
+	return 0;
+}
+static void dlm_debug_shutdown(struct dlm_ctxt *dlm)
+{
+}
+static int dlm_create_debugfs_subroot(struct dlm_ctxt *dlm)
+{
+	return 0;
+}
+static void dlm_destroy_debugfs_subroot(struct dlm_ctxt *dlm)
+{
+}
+static int dlm_create_debugfs_root(void)
+{
+	return 0;
+}
+static void dlm_destroy_debugfs_root(void)
+{
+}
+
+#endif	/* CONFIG_DEBUG_FS */
+#endif	/* DLMDEBUG_H */
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 638d2ebb892..63f8125824e 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -33,6 +33,7 @@
 #include <linux/spinlock.h>
 #include <linux/delay.h>
 #include <linux/err.h>
+#include <linux/debugfs.h>
 
 #include "cluster/heartbeat.h"
 #include "cluster/nodemanager.h"
@@ -40,8 +41,8 @@
 
 #include "dlmapi.h"
 #include "dlmcommon.h"
-
 #include "dlmdomain.h"
+#include "dlmdebug.h"
 
 #include "dlmver.h"
 
@@ -298,6 +299,8 @@ static int dlm_wait_on_domain_helper(const char *domain)
 
 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
 {
+	dlm_destroy_debugfs_subroot(dlm);
+
 	if (dlm->lockres_hash)
 		dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
 
@@ -395,6 +398,7 @@ static void dlm_destroy_dlm_worker(struct dlm_ctxt *dlm)
 static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
 {
 	dlm_unregister_domain_handlers(dlm);
+	dlm_debug_shutdown(dlm);
 	dlm_complete_thread(dlm);
 	dlm_complete_recovery_thread(dlm);
 	dlm_destroy_dlm_worker(dlm);
@@ -644,6 +648,7 @@ int dlm_shutting_down(struct dlm_ctxt *dlm)
 void dlm_unregister_domain(struct dlm_ctxt *dlm)
 {
 	int leave = 0;
+	struct dlm_lock_resource *res;
 
 	spin_lock(&dlm_domain_lock);
 	BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
@@ -673,6 +678,15 @@ void dlm_unregister_domain(struct dlm_ctxt *dlm)
 			msleep(500);
 			mlog(0, "%s: more migration to do\n", dlm->name);
 		}
+
+		/* This list should be empty. If not, print remaining lockres */
+		if (!list_empty(&dlm->tracking_list)) {
+			mlog(ML_ERROR, "Following lockres' are still on the "
+			     "tracking list:\n");
+			list_for_each_entry(res, &dlm->tracking_list, tracking)
+				dlm_print_one_lock_resource(res);
+		}
+
 		dlm_mark_domain_leaving(dlm);
 		dlm_leave_domain(dlm);
 		dlm_complete_dlm_shutdown(dlm);
@@ -713,14 +727,46 @@ static int dlm_query_join_proto_check(char *proto_type, int node,
 	return rc;
 }
 
+/*
+ * struct dlm_query_join_packet is made up of four one-byte fields.  They
+ * are effectively in big-endian order already.  However, little-endian
+ * machines swap them before putting the packet on the wire (because
+ * query_join's response is a status, and that status is treated as a u32
+ * on the wire).  Thus, a big-endian and little-endian machines will treat
+ * this structure differently.
+ *
+ * The solution is to have little-endian machines swap the structure when
+ * converting from the structure to the u32 representation.  This will
+ * result in the structure having the correct format on the wire no matter
+ * the host endian format.
+ */
+static void dlm_query_join_packet_to_wire(struct dlm_query_join_packet *packet,
+					  u32 *wire)
+{
+	union dlm_query_join_response response;
+
+	response.packet = *packet;
+	*wire = cpu_to_be32(response.intval);
+}
+
+static void dlm_query_join_wire_to_packet(u32 wire,
+					  struct dlm_query_join_packet *packet)
+{
+	union dlm_query_join_response response;
+
+	response.intval = cpu_to_be32(wire);
+	*packet = response.packet;
+}
+
 static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
 				  void **ret_data)
 {
 	struct dlm_query_join_request *query;
-	union dlm_query_join_response response = {
-		.packet.code = JOIN_DISALLOW,
+	struct dlm_query_join_packet packet = {
+		.code = JOIN_DISALLOW,
 	};
 	struct dlm_ctxt *dlm = NULL;
+	u32 response;
 	u8 nodenum;
 
 	query = (struct dlm_query_join_request *) msg->buf;
@@ -737,11 +783,11 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
 		mlog(0, "node %u is not in our live map yet\n",
 		     query->node_idx);
 
-		response.packet.code = JOIN_DISALLOW;
+		packet.code = JOIN_DISALLOW;
 		goto respond;
 	}
 
-	response.packet.code = JOIN_OK_NO_MAP;
+	packet.code = JOIN_OK_NO_MAP;
 
 	spin_lock(&dlm_domain_lock);
 	dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
@@ -760,7 +806,7 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
 				mlog(0, "disallow join as node %u does not "
 				     "have node %u in its nodemap\n",
 				     query->node_idx, nodenum);
-				response.packet.code = JOIN_DISALLOW;
+				packet.code = JOIN_DISALLOW;
 				goto unlock_respond;
 			}
 		}
@@ -780,23 +826,23 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
 			/*If this is a brand new context and we
 			 * haven't started our join process yet, then
 			 * the other node won the race. */
-			response.packet.code = JOIN_OK_NO_MAP;
+			packet.code = JOIN_OK_NO_MAP;
 		} else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
 			/* Disallow parallel joins. */
-			response.packet.code = JOIN_DISALLOW;
+			packet.code = JOIN_DISALLOW;
 		} else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
 			mlog(0, "node %u trying to join, but recovery "
 			     "is ongoing.\n", bit);
-			response.packet.code = JOIN_DISALLOW;
+			packet.code = JOIN_DISALLOW;
 		} else if (test_bit(bit, dlm->recovery_map)) {
 			mlog(0, "node %u trying to join, but it "
 			     "still needs recovery.\n", bit);
-			response.packet.code = JOIN_DISALLOW;
+			packet.code = JOIN_DISALLOW;
 		} else if (test_bit(bit, dlm->domain_map)) {
 			mlog(0, "node %u trying to join, but it "
 			     "is still in the domain! needs recovery?\n",
 			     bit);
-			response.packet.code = JOIN_DISALLOW;
+			packet.code = JOIN_DISALLOW;
 		} else {
 			/* Alright we're fully a part of this domain
 			 * so we keep some state as to who's joining
@@ -807,19 +853,15 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
 			if (dlm_query_join_proto_check("DLM", bit,
 						       &dlm->dlm_locking_proto,
 						       &query->dlm_proto)) {
-				response.packet.code =
-					JOIN_PROTOCOL_MISMATCH;
+				packet.code = JOIN_PROTOCOL_MISMATCH;
 			} else if (dlm_query_join_proto_check("fs", bit,
 							      &dlm->fs_locking_proto,
 							      &query->fs_proto)) {
-				response.packet.code =
-					JOIN_PROTOCOL_MISMATCH;
+				packet.code = JOIN_PROTOCOL_MISMATCH;
 			} else {
-				response.packet.dlm_minor =
-					query->dlm_proto.pv_minor;
-				response.packet.fs_minor =
-					query->fs_proto.pv_minor;
-				response.packet.code = JOIN_OK;
+				packet.dlm_minor = query->dlm_proto.pv_minor;
+				packet.fs_minor = query->fs_proto.pv_minor;
+				packet.code = JOIN_OK;
 				__dlm_set_joining_node(dlm, query->node_idx);
 			}
 		}
@@ -830,9 +872,10 @@ unlock_respond:
 	spin_unlock(&dlm_domain_lock);
 
 respond:
-	mlog(0, "We respond with %u\n", response.packet.code);
+	mlog(0, "We respond with %u\n", packet.code);
 
-	return response.intval;
+	dlm_query_join_packet_to_wire(&packet, &response);
+	return response;
 }
 
 static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
@@ -937,7 +980,7 @@ static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
 			 sizeof(unsigned long))) {
 		mlog(ML_ERROR,
 		     "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
-		     map_size, BITS_TO_LONGS(O2NM_MAX_NODES));
+		     map_size, (unsigned)BITS_TO_LONGS(O2NM_MAX_NODES));
 		return -EINVAL;
 	}
 
@@ -968,7 +1011,8 @@ static int dlm_request_join(struct dlm_ctxt *dlm,
 {
 	int status;
 	struct dlm_query_join_request join_msg;
-	union dlm_query_join_response join_resp;
+	struct dlm_query_join_packet packet;
+	u32 join_resp;
 
 	mlog(0, "querying node %d\n", node);
 
@@ -984,11 +1028,12 @@ static int dlm_request_join(struct dlm_ctxt *dlm,
 
 	status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
 				    sizeof(join_msg), node,
-				    &join_resp.intval);
+				    &join_resp);
 	if (status < 0 && status != -ENOPROTOOPT) {
 		mlog_errno(status);
 		goto bail;
 	}
+	dlm_query_join_wire_to_packet(join_resp, &packet);
 
 	/* -ENOPROTOOPT from the net code means the other side isn't
 	    listening for our message type -- that's fine, it means
@@ -997,10 +1042,10 @@ static int dlm_request_join(struct dlm_ctxt *dlm,
 	if (status == -ENOPROTOOPT) {
 		status = 0;
 		*response = JOIN_OK_NO_MAP;
-	} else if (join_resp.packet.code == JOIN_DISALLOW ||
-		   join_resp.packet.code == JOIN_OK_NO_MAP) {
-		*response = join_resp.packet.code;
-	} else if (join_resp.packet.code == JOIN_PROTOCOL_MISMATCH) {
+	} else if (packet.code == JOIN_DISALLOW ||
+		   packet.code == JOIN_OK_NO_MAP) {
+		*response = packet.code;
+	} else if (packet.code == JOIN_PROTOCOL_MISMATCH) {
 		mlog(ML_NOTICE,
 		     "This node requested DLM locking protocol %u.%u and "
 		     "filesystem locking protocol %u.%u.  At least one of "
@@ -1012,14 +1057,12 @@ static int dlm_request_join(struct dlm_ctxt *dlm,
 		     dlm->fs_locking_proto.pv_minor,
 		     node);
 		status = -EPROTO;
-		*response = join_resp.packet.code;
-	} else if (join_resp.packet.code == JOIN_OK) {
-		*response = join_resp.packet.code;
+		*response = packet.code;
+	} else if (packet.code == JOIN_OK) {
+		*response = packet.code;
 		/* Use the same locking protocol as the remote node */
-		dlm->dlm_locking_proto.pv_minor =
-			join_resp.packet.dlm_minor;
-		dlm->fs_locking_proto.pv_minor =
-			join_resp.packet.fs_minor;
+		dlm->dlm_locking_proto.pv_minor = packet.dlm_minor;
+		dlm->fs_locking_proto.pv_minor = packet.fs_minor;
 		mlog(0,
 		     "Node %d responds JOIN_OK with DLM locking protocol "
 		     "%u.%u and fs locking protocol %u.%u\n",
@@ -1031,11 +1074,11 @@ static int dlm_request_join(struct dlm_ctxt *dlm,
 	} else {
 		status = -EINVAL;
 		mlog(ML_ERROR, "invalid response %d from node %u\n",
-		     join_resp.packet.code, node);
+		     packet.code, node);
 	}
 
 	mlog(0, "status %d, node %d response is %d\n", status, node,
-		  *response);
+	     *response);
 
 bail:
 	return status;
@@ -1376,6 +1419,12 @@ static int dlm_join_domain(struct dlm_ctxt *dlm)
 		goto bail;
 	}
 
+	status = dlm_debug_init(dlm);
+	if (status < 0) {
+		mlog_errno(status);
+		goto bail;
+	}
+
 	status = dlm_launch_thread(dlm);
 	if (status < 0) {
 		mlog_errno(status);
@@ -1443,6 +1492,7 @@ bail:
 
 	if (status) {
 		dlm_unregister_domain_handlers(dlm);
+		dlm_debug_shutdown(dlm);
 		dlm_complete_thread(dlm);
 		dlm_complete_recovery_thread(dlm);
 		dlm_destroy_dlm_worker(dlm);
@@ -1455,6 +1505,7 @@ static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
 				u32 key)
 {
 	int i;
+	int ret;
 	struct dlm_ctxt *dlm = NULL;
 
 	dlm = kzalloc(sizeof(*dlm), GFP_KERNEL);
@@ -1487,6 +1538,15 @@ static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
 	dlm->key = key;
 	dlm->node_num = o2nm_this_node();
 
+	ret = dlm_create_debugfs_subroot(dlm);
+	if (ret < 0) {
+		dlm_free_pagevec((void **)dlm->lockres_hash, DLM_HASH_PAGES);
+		kfree(dlm->name);
+		kfree(dlm);
+		dlm = NULL;
+		goto leave;
+	}
+
 	spin_lock_init(&dlm->spinlock);
 	spin_lock_init(&dlm->master_lock);
 	spin_lock_init(&dlm->ast_lock);
@@ -1497,6 +1557,7 @@ static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
 	INIT_LIST_HEAD(&dlm->reco.node_data);
 	INIT_LIST_HEAD(&dlm->purge_list);
 	INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
+	INIT_LIST_HEAD(&dlm->tracking_list);
 	dlm->reco.state = 0;
 
 	INIT_LIST_HEAD(&dlm->pending_asts);
@@ -1787,21 +1848,49 @@ static int __init dlm_init(void)
 	dlm_print_version();
 
 	status = dlm_init_mle_cache();
-	if (status)
-		return -1;
+	if (status) {
+		mlog(ML_ERROR, "Could not create o2dlm_mle slabcache\n");
+		goto error;
+	}
+
+	status = dlm_init_master_caches();
+	if (status) {
+		mlog(ML_ERROR, "Could not create o2dlm_lockres and "
+		     "o2dlm_lockname slabcaches\n");
+		goto error;
+	}
+
+	status = dlm_init_lock_cache();
+	if (status) {
+		mlog(ML_ERROR, "Count not create o2dlm_lock slabcache\n");
+		goto error;
+	}
 
 	status = dlm_register_net_handlers();
 	if (status) {
-		dlm_destroy_mle_cache();
-		return -1;
+		mlog(ML_ERROR, "Unable to register network handlers\n");
+		goto error;
 	}
 
+	status = dlm_create_debugfs_root();
+	if (status)
+		goto error;
+
 	return 0;
+error:
+	dlm_unregister_net_handlers();
+	dlm_destroy_lock_cache();
+	dlm_destroy_master_caches();
+	dlm_destroy_mle_cache();
+	return -1;
 }
 
 static void __exit dlm_exit (void)
 {
+	dlm_destroy_debugfs_root();
 	dlm_unregister_net_handlers();
+	dlm_destroy_lock_cache();
+	dlm_destroy_master_caches();
 	dlm_destroy_mle_cache();
 }
 
diff --git a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c
index 52578d907d9..83a9f2972ac 100644
--- a/fs/ocfs2/dlm/dlmlock.c
+++ b/fs/ocfs2/dlm/dlmlock.c
@@ -53,6 +53,8 @@
 #define MLOG_MASK_PREFIX ML_DLM
 #include "cluster/masklog.h"
 
+static struct kmem_cache *dlm_lock_cache = NULL;
+
 static DEFINE_SPINLOCK(dlm_cookie_lock);
 static u64 dlm_next_cookie = 1;
 
@@ -64,6 +66,22 @@ static void dlm_init_lock(struct dlm_lock *newlock, int type,
 static void dlm_lock_release(struct kref *kref);
 static void dlm_lock_detach_lockres(struct dlm_lock *lock);
 
+int dlm_init_lock_cache(void)
+{
+	dlm_lock_cache = kmem_cache_create("o2dlm_lock",
+					   sizeof(struct dlm_lock),
+					   0, SLAB_HWCACHE_ALIGN, NULL);
+	if (dlm_lock_cache == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+void dlm_destroy_lock_cache(void)
+{
+	if (dlm_lock_cache)
+		kmem_cache_destroy(dlm_lock_cache);
+}
+
 /* Tell us whether we can grant a new lock request.
  * locking:
  *   caller needs:  res->spinlock
@@ -353,7 +371,7 @@ static void dlm_lock_release(struct kref *kref)
 		mlog(0, "freeing kernel-allocated lksb\n");
 		kfree(lock->lksb);
 	}
-	kfree(lock);
+	kmem_cache_free(dlm_lock_cache, lock);
 }
 
 /* associate a lock with it's lockres, getting a ref on the lockres */
@@ -412,7 +430,7 @@ struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
 	struct dlm_lock *lock;
 	int kernel_allocated = 0;
 
-	lock = kzalloc(sizeof(*lock), GFP_NOFS);
+	lock = (struct dlm_lock *) kmem_cache_zalloc(dlm_lock_cache, GFP_NOFS);
 	if (!lock)
 		return NULL;
 
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index a54d33d95ad..efc015c6128 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -48,47 +48,11 @@
 #include "dlmapi.h"
 #include "dlmcommon.h"
 #include "dlmdomain.h"
+#include "dlmdebug.h"
 
 #define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_MASTER)
 #include "cluster/masklog.h"
 
-enum dlm_mle_type {
-	DLM_MLE_BLOCK,
-	DLM_MLE_MASTER,
-	DLM_MLE_MIGRATION
-};
-
-struct dlm_lock_name
-{
-	u8 len;
-	u8 name[DLM_LOCKID_NAME_MAX];
-};
-
-struct dlm_master_list_entry
-{
-	struct list_head list;
-	struct list_head hb_events;
-	struct dlm_ctxt *dlm;
-	spinlock_t spinlock;
-	wait_queue_head_t wq;
-	atomic_t woken;
-	struct kref mle_refs;
-	int inuse;
-	unsigned long maybe_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
-	unsigned long vote_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
-	unsigned long response_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
-	unsigned long node_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
-	u8 master;
-	u8 new_master;
-	enum dlm_mle_type type;
-	struct o2hb_callback_func mle_hb_up;
-	struct o2hb_callback_func mle_hb_down;
-	union {
-		struct dlm_lock_resource *res;
-		struct dlm_lock_name name;
-	} u;
-};
-
 static void dlm_mle_node_down(struct dlm_ctxt *dlm,
 			      struct dlm_master_list_entry *mle,
 			      struct o2nm_node *node,
@@ -128,98 +92,10 @@ static inline int dlm_mle_equal(struct dlm_ctxt *dlm,
 	return 1;
 }
 
-#define dlm_print_nodemap(m)  _dlm_print_nodemap(m,#m)
-static void _dlm_print_nodemap(unsigned long *map, const char *mapname)
-{
-	int i;
-	printk("%s=[ ", mapname);
-	for (i=0; i<O2NM_MAX_NODES; i++)
-		if (test_bit(i, map))
-			printk("%d ", i);
-	printk("]");
-}
-
-static void dlm_print_one_mle(struct dlm_master_list_entry *mle)
-{
-	int refs;
-	char *type;
-	char attached;
-	u8 master;
-	unsigned int namelen;
-	const char *name;
-	struct kref *k;
-	unsigned long *maybe = mle->maybe_map,
-		      *vote = mle->vote_map,
-		      *resp = mle->response_map,
-		      *node = mle->node_map;
-
-	k = &mle->mle_refs;
-	if (mle->type == DLM_MLE_BLOCK)
-		type = "BLK";
-	else if (mle->type == DLM_MLE_MASTER)
-		type = "MAS";
-	else
-		type = "MIG";
-	refs = atomic_read(&k->refcount);
-	master = mle->master;
-	attached = (list_empty(&mle->hb_events) ? 'N' : 'Y');
-
-	if (mle->type != DLM_MLE_MASTER) {
-		namelen = mle->u.name.len;
-		name = mle->u.name.name;
-	} else {
-		namelen = mle->u.res->lockname.len;
-		name = mle->u.res->lockname.name;
-	}
-
-	mlog(ML_NOTICE, "%.*s: %3s refs=%3d mas=%3u new=%3u evt=%c inuse=%d ",
-		  namelen, name, type, refs, master, mle->new_master, attached,
-		  mle->inuse);
-	dlm_print_nodemap(maybe);
-	printk(", ");
-	dlm_print_nodemap(vote);
-	printk(", ");
-	dlm_print_nodemap(resp);
-	printk(", ");
-	dlm_print_nodemap(node);
-	printk(", ");
-	printk("\n");
-}
-
-#if 0
-/* Code here is included but defined out as it aids debugging */
-
-static void dlm_dump_mles(struct dlm_ctxt *dlm)
-{
-	struct dlm_master_list_entry *mle;
-	
-	mlog(ML_NOTICE, "dumping all mles for domain %s:\n", dlm->name);
-	spin_lock(&dlm->master_lock);
-	list_for_each_entry(mle, &dlm->master_list, list)
-		dlm_print_one_mle(mle);
-	spin_unlock(&dlm->master_lock);
-}
-
-int dlm_dump_all_mles(const char __user *data, unsigned int len)
-{
-	struct dlm_ctxt *dlm;
-
-	spin_lock(&dlm_domain_lock);
-	list_for_each_entry(dlm, &dlm_domains, list) {
-		mlog(ML_NOTICE, "found dlm: %p, name=%s\n", dlm, dlm->name);
-		dlm_dump_mles(dlm);
-	}
-	spin_unlock(&dlm_domain_lock);
-	return len;
-}
-EXPORT_SYMBOL_GPL(dlm_dump_all_mles);
-
-#endif  /*  0  */
-
-
+static struct kmem_cache *dlm_lockres_cache = NULL;
+static struct kmem_cache *dlm_lockname_cache = NULL;
 static struct kmem_cache *dlm_mle_cache = NULL;
 
-
 static void dlm_mle_release(struct kref *kref);
 static void dlm_init_mle(struct dlm_master_list_entry *mle,
 			enum dlm_mle_type type,
@@ -507,7 +383,7 @@ static void dlm_mle_node_up(struct dlm_ctxt *dlm,
 
 int dlm_init_mle_cache(void)
 {
-	dlm_mle_cache = kmem_cache_create("dlm_mle_cache",
+	dlm_mle_cache = kmem_cache_create("o2dlm_mle",
 					  sizeof(struct dlm_master_list_entry),
 					  0, SLAB_HWCACHE_ALIGN,
 					  NULL);
@@ -560,6 +436,35 @@ static void dlm_mle_release(struct kref *kref)
  * LOCK RESOURCE FUNCTIONS
  */
 
+int dlm_init_master_caches(void)
+{
+	dlm_lockres_cache = kmem_cache_create("o2dlm_lockres",
+					      sizeof(struct dlm_lock_resource),
+					      0, SLAB_HWCACHE_ALIGN, NULL);
+	if (!dlm_lockres_cache)
+		goto bail;
+
+	dlm_lockname_cache = kmem_cache_create("o2dlm_lockname",
+					       DLM_LOCKID_NAME_MAX, 0,
+					       SLAB_HWCACHE_ALIGN, NULL);
+	if (!dlm_lockname_cache)
+		goto bail;
+
+	return 0;
+bail:
+	dlm_destroy_master_caches();
+	return -ENOMEM;
+}
+
+void dlm_destroy_master_caches(void)
+{
+	if (dlm_lockname_cache)
+		kmem_cache_destroy(dlm_lockname_cache);
+
+	if (dlm_lockres_cache)
+		kmem_cache_destroy(dlm_lockres_cache);
+}
+
 static void dlm_set_lockres_owner(struct dlm_ctxt *dlm,
 				  struct dlm_lock_resource *res,
 				  u8 owner)
@@ -610,6 +515,14 @@ static void dlm_lockres_release(struct kref *kref)
 	mlog(0, "destroying lockres %.*s\n", res->lockname.len,
 	     res->lockname.name);
 
+	if (!list_empty(&res->tracking))
+		list_del_init(&res->tracking);
+	else {
+		mlog(ML_ERROR, "Resource %.*s not on the Tracking list\n",
+		     res->lockname.len, res->lockname.name);
+		dlm_print_one_lock_resource(res);
+	}
+
 	if (!hlist_unhashed(&res->hash_node) ||
 	    !list_empty(&res->granted) ||
 	    !list_empty(&res->converting) ||
@@ -642,9 +555,9 @@ static void dlm_lockres_release(struct kref *kref)
 	BUG_ON(!list_empty(&res->recovering));
 	BUG_ON(!list_empty(&res->purge));
 
-	kfree(res->lockname.name);
+	kmem_cache_free(dlm_lockname_cache, (void *)res->lockname.name);
 
-	kfree(res);
+	kmem_cache_free(dlm_lockres_cache, res);
 }
 
 void dlm_lockres_put(struct dlm_lock_resource *res)
@@ -677,6 +590,7 @@ static void dlm_init_lockres(struct dlm_ctxt *dlm,
 	INIT_LIST_HEAD(&res->dirty);
 	INIT_LIST_HEAD(&res->recovering);
 	INIT_LIST_HEAD(&res->purge);
+	INIT_LIST_HEAD(&res->tracking);
 	atomic_set(&res->asts_reserved, 0);
 	res->migration_pending = 0;
 	res->inflight_locks = 0;
@@ -692,6 +606,8 @@ static void dlm_init_lockres(struct dlm_ctxt *dlm,
 
 	res->last_used = 0;
 
+	list_add_tail(&res->tracking, &dlm->tracking_list);
+
 	memset(res->lvb, 0, DLM_LVB_LEN);
 	memset(res->refmap, 0, sizeof(res->refmap));
 }
@@ -700,20 +616,28 @@ struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
 				   const char *name,
 				   unsigned int namelen)
 {
-	struct dlm_lock_resource *res;
+	struct dlm_lock_resource *res = NULL;
 
-	res = kmalloc(sizeof(struct dlm_lock_resource), GFP_NOFS);
+	res = (struct dlm_lock_resource *)
+				kmem_cache_zalloc(dlm_lockres_cache, GFP_NOFS);
 	if (!res)
-		return NULL;
+		goto error;
 
-	res->lockname.name = kmalloc(namelen, GFP_NOFS);
-	if (!res->lockname.name) {
-		kfree(res);
-		return NULL;
-	}
+	res->lockname.name = (char *)
+				kmem_cache_zalloc(dlm_lockname_cache, GFP_NOFS);
+	if (!res->lockname.name)
+		goto error;
 
 	dlm_init_lockres(dlm, res, name, namelen);
 	return res;
+
+error:
+	if (res && res->lockname.name)
+		kmem_cache_free(dlm_lockname_cache, (void *)res->lockname.name);
+
+	if (res)
+		kmem_cache_free(dlm_lockres_cache, res);
+	return NULL;
 }
 
 void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
@@ -1663,7 +1587,12 @@ way_up_top:
 		dlm_put_mle(tmpmle);
 	}
 send_response:
-
+	/*
+	 * __dlm_lookup_lockres() grabbed a reference to this lockres.
+	 * The reference is released by dlm_assert_master_worker() under
+	 * the call to dlm_dispatch_assert_master().  If
+	 * dlm_assert_master_worker() isn't called, we drop it here.
+	 */
 	if (dispatch_assert) {
 		if (response != DLM_MASTER_RESP_YES)
 			mlog(ML_ERROR, "invalid response %d\n", response);
@@ -1678,7 +1607,11 @@ send_response:
 		if (ret < 0) {
 			mlog(ML_ERROR, "failed to dispatch assert master work\n");
 			response = DLM_MASTER_RESP_ERROR;
+			dlm_lockres_put(res);
 		}
+	} else {
+		if (res)
+			dlm_lockres_put(res);
 	}
 
 	dlm_put(dlm);
@@ -1695,9 +1628,9 @@ send_response:
  * can periodically run all locks owned by this node
  * and re-assert across the cluster...
  */
-int dlm_do_assert_master(struct dlm_ctxt *dlm,
-			 struct dlm_lock_resource *res,
-			 void *nodemap, u32 flags)
+static int dlm_do_assert_master(struct dlm_ctxt *dlm,
+				struct dlm_lock_resource *res,
+				void *nodemap, u32 flags)
 {
 	struct dlm_assert_master assert;
 	int to, tmpret;
@@ -2348,7 +2281,7 @@ int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
 			mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
 		     	"but it is already dropped!\n", dlm->name,
 		     	res->lockname.len, res->lockname.name, node);
-			__dlm_print_one_lock_resource(res);
+			dlm_print_one_lock_resource(res);
 		}
 		ret = 0;
 		goto done;
@@ -2408,7 +2341,7 @@ static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data)
 		mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
 		     "but it is already dropped!\n", dlm->name,
 		     res->lockname.len, res->lockname.name, node);
-		__dlm_print_one_lock_resource(res);
+		dlm_print_one_lock_resource(res);
 	}
 
 	dlm_lockres_put(res);
@@ -2933,6 +2866,9 @@ static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm,
 				dlm_lockres_clear_refmap_bit(lock->ml.node, res);
 				list_del_init(&lock->list);
 				dlm_lock_put(lock);
+				/* In a normal unlock, we would have added a
+				 * DLM_UNLOCK_FREE_LOCK action. Force it. */
+				dlm_lock_put(lock);
 			}
 		}
 		queue++;
diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c
index 91f747b8a53..bcb9260c373 100644
--- a/fs/ocfs2/dlm/dlmrecovery.c
+++ b/fs/ocfs2/dlm/dlmrecovery.c
@@ -519,9 +519,9 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
 	return 0;
 
 master_here:
-	mlog(0, "(%d) mastering recovery of %s:%u here(this=%u)!\n",
-	     task_pid_nr(dlm->dlm_reco_thread_task),
-	     dlm->name, dlm->reco.dead_node, dlm->node_num);
+	mlog(ML_NOTICE, "(%d) Node %u is the Recovery Master for the Dead Node "
+	     "%u for Domain %s\n", task_pid_nr(dlm->dlm_reco_thread_task),
+	     dlm->node_num, dlm->reco.dead_node, dlm->name);
 
 	status = dlm_remaster_locks(dlm, dlm->reco.dead_node);
 	if (status < 0) {
@@ -1191,7 +1191,7 @@ static int dlm_add_lock_to_array(struct dlm_lock *lock,
 			    (ml->type == LKM_EXMODE ||
 			     memcmp(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN))) {
 				mlog(ML_ERROR, "mismatched lvbs!\n");
-				__dlm_print_one_lock_resource(lock->lockres);
+				dlm_print_one_lock_resource(lock->lockres);
 				BUG();
 			}
 			memcpy(mres->lvb, lock->lksb->lvb, DLM_LVB_LEN);
@@ -1327,6 +1327,7 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
 		(struct dlm_migratable_lockres *)msg->buf;
 	int ret = 0;
 	u8 real_master;
+	u8 extra_refs = 0;
 	char *buf = NULL;
 	struct dlm_work_item *item = NULL;
 	struct dlm_lock_resource *res = NULL;
@@ -1404,16 +1405,28 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
 		__dlm_insert_lockres(dlm, res);
 		spin_unlock(&dlm->spinlock);
 
+		/* Add an extra ref for this lock-less lockres lest the
+		 * dlm_thread purges it before we get the chance to add
+		 * locks to it */
+		dlm_lockres_get(res);
+
+		/* There are three refs that need to be put.
+		 * 1. Taken above.
+		 * 2. kref_init in dlm_new_lockres()->dlm_init_lockres().
+		 * 3. dlm_lookup_lockres()
+		 * The first one is handled at the end of this function. The
+		 * other two are handled in the worker thread after locks have
+		 * been attached. Yes, we don't wait for purge time to match
+		 * kref_init. The lockres will still have atleast one ref
+		 * added because it is in the hash __dlm_insert_lockres() */
+		extra_refs++;
+
 		/* now that the new lockres is inserted,
 		 * make it usable by other processes */
 		spin_lock(&res->spinlock);
 		res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
 		spin_unlock(&res->spinlock);
 		wake_up(&res->wq);
-
-		/* add an extra ref for just-allocated lockres 
-		 * otherwise the lockres will be purged immediately */
-		dlm_lockres_get(res);
 	}
 
 	/* at this point we have allocated everything we need,
@@ -1443,12 +1456,17 @@ int dlm_mig_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
 	dlm_init_work_item(dlm, item, dlm_mig_lockres_worker, buf);
 	item->u.ml.lockres = res; /* already have a ref */
 	item->u.ml.real_master = real_master;
+	item->u.ml.extra_ref = extra_refs;
 	spin_lock(&dlm->work_lock);
 	list_add_tail(&item->list, &dlm->work_list);
 	spin_unlock(&dlm->work_lock);
 	queue_work(dlm->dlm_worker, &dlm->dispatched_work);
 
 leave:
+	/* One extra ref taken needs to be put here */
+	if (extra_refs)
+		dlm_lockres_put(res);
+
 	dlm_put(dlm);
 	if (ret < 0) {
 		if (buf)
@@ -1464,17 +1482,19 @@ leave:
 
 static void dlm_mig_lockres_worker(struct dlm_work_item *item, void *data)
 {
-	struct dlm_ctxt *dlm = data;
+	struct dlm_ctxt *dlm;
 	struct dlm_migratable_lockres *mres;
 	int ret = 0;
 	struct dlm_lock_resource *res;
 	u8 real_master;
+	u8 extra_ref;
 
 	dlm = item->dlm;
 	mres = (struct dlm_migratable_lockres *)data;
 
 	res = item->u.ml.lockres;
 	real_master = item->u.ml.real_master;
+	extra_ref = item->u.ml.extra_ref;
 
 	if (real_master == DLM_LOCK_RES_OWNER_UNKNOWN) {
 		/* this case is super-rare. only occurs if
@@ -1517,6 +1537,12 @@ again:
 	}
 
 leave:
+	/* See comment in dlm_mig_lockres_handler() */
+	if (res) {
+		if (extra_ref)
+			dlm_lockres_put(res);
+		dlm_lockres_put(res);
+	}
 	kfree(data);
 	mlog_exit(ret);
 }
@@ -1644,7 +1670,8 @@ int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
 				/* retry!? */
 				BUG();
 			}
-		}
+		} else /* put.. incase we are not the master */
+			dlm_lockres_put(res);
 		spin_unlock(&res->spinlock);
 	}
 	spin_unlock(&dlm->spinlock);
@@ -1921,6 +1948,7 @@ void dlm_move_lockres_to_recovery_list(struct dlm_ctxt *dlm,
 		     "Recovering res %s:%.*s, is already on recovery list!\n",
 		     dlm->name, res->lockname.len, res->lockname.name);
 		list_del_init(&res->recovering);
+		dlm_lockres_put(res);
 	}
 	/* We need to hold a reference while on the recovery list */
 	dlm_lockres_get(res);
@@ -2130,11 +2158,16 @@ static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
 	assert_spin_locked(&dlm->spinlock);
 	assert_spin_locked(&res->spinlock);
 
+	/* We do two dlm_lock_put(). One for removing from list and the other is
+	 * to force the DLM_UNLOCK_FREE_LOCK action so as to free the locks */
+
 	/* TODO: check pending_asts, pending_basts here */
 	list_for_each_entry_safe(lock, next, &res->granted, list) {
 		if (lock->ml.node == dead_node) {
 			list_del_init(&lock->list);
 			dlm_lock_put(lock);
+			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
+			dlm_lock_put(lock);
 			freed++;
 		}
 	}
@@ -2142,6 +2175,8 @@ static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
 		if (lock->ml.node == dead_node) {
 			list_del_init(&lock->list);
 			dlm_lock_put(lock);
+			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
+			dlm_lock_put(lock);
 			freed++;
 		}
 	}
@@ -2149,6 +2184,8 @@ static void dlm_free_dead_locks(struct dlm_ctxt *dlm,
 		if (lock->ml.node == dead_node) {
 			list_del_init(&lock->list);
 			dlm_lock_put(lock);
+			/* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
+			dlm_lock_put(lock);
 			freed++;
 		}
 	}
diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c
index cebd089f895..4060bb328bc 100644
--- a/fs/ocfs2/dlm/dlmthread.c
+++ b/fs/ocfs2/dlm/dlmthread.c
@@ -176,12 +176,14 @@ static int dlm_purge_lockres(struct dlm_ctxt *dlm,
 	     res->lockname.name, master);
 
 	if (!master) {
+		/* drop spinlock...  retake below */
+		spin_unlock(&dlm->spinlock);
+
 		spin_lock(&res->spinlock);
 		/* This ensures that clear refmap is sent after the set */
 		__dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG);
 		spin_unlock(&res->spinlock);
-		/* drop spinlock to do messaging, retake below */
-		spin_unlock(&dlm->spinlock);
+
 		/* clear our bit from the master's refmap, ignore errors */
 		ret = dlm_drop_lockres_ref(dlm, res);
 		if (ret < 0) {