1 files changed, 387 insertions, 377 deletions

diff --git a/fs/dlm/debug_fs.c b/fs/dlm/debug_fs.c
index b969deef9ebb..700a0cbb2f14 100644
--- a/fs/dlm/debug_fs.c
+++ b/fs/dlm/debug_fs.c
@@ -1,30 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /******************************************************************************
 *******************************************************************************
 **
 **  Copyright (C) 2005-2009 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
-**  of the GNU General Public License v.2.
 **
 *******************************************************************************
 ******************************************************************************/
 
 #include <linux/pagemap.h>
 #include <linux/seq_file.h>
-#include <linux/module.h>
+#include <linux/init.h>
 #include <linux/ctype.h>
 #include <linux/debugfs.h>
 #include <linux/slab.h>
 
 #include "dlm_internal.h"
+#include "midcomms.h"
 #include "lock.h"
+#include "ast.h"
 
 #define DLM_DEBUG_BUF_LEN 4096
 static char debug_buf[DLM_DEBUG_BUF_LEN];
 static struct mutex debug_buf_lock;
 
 static struct dentry *dlm_root;
+static struct dentry *dlm_comms;
 
 static char *print_lockmode(int mode)
 {
@@ -48,8 +49,8 @@ static char *print_lockmode(int mode)
 	}
 }
 
-static int print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
-			      struct dlm_rsb *res)
+static void print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
+			       struct dlm_rsb *res)
 {
 	seq_printf(s, "%08x %s", lkb->lkb_id, print_lockmode(lkb->lkb_grmode));
 
@@ -68,21 +69,17 @@ static int print_format1_lock(struct seq_file *s, struct dlm_lkb *lkb,
 	if (lkb->lkb_wait_type)
 		seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
 
-	return seq_printf(s, "\n");
+	seq_putc(s, '\n');
 }
 
-static int print_format1(struct dlm_rsb *res, struct seq_file *s)
+static void print_format1(struct dlm_rsb *res, struct seq_file *s)
 {
 	struct dlm_lkb *lkb;
 	int i, lvblen = res->res_ls->ls_lvblen, recover_list, root_list;
-	int rv;
 
 	lock_rsb(res);
 
-	rv = seq_printf(s, "\nResource %p Name (len=%d) \"",
-			res, res->res_length);
-	if (rv)
-		goto out;
+	seq_printf(s, "\nResource %p Name (len=%d) \"", res, res->res_length);
 
 	for (i = 0; i < res->res_length; i++) {
 		if (isprint(res->res_name[i]))
@@ -92,32 +89,31 @@ static int print_format1(struct dlm_rsb *res, struct seq_file *s)
 	}
 
 	if (res->res_nodeid > 0)
-		rv = seq_printf(s, "\"  \nLocal Copy, Master is node %d\n",
-				res->res_nodeid);
+		seq_printf(s, "\"\nLocal Copy, Master is node %d\n",
+			   res->res_nodeid);
 	else if (res->res_nodeid == 0)
-		rv = seq_printf(s, "\"  \nMaster Copy\n");
+		seq_puts(s, "\"\nMaster Copy\n");
 	else if (res->res_nodeid == -1)
-		rv = seq_printf(s, "\"  \nLooking up master (lkid %x)\n",
-			   	res->res_first_lkid);
+		seq_printf(s, "\"\nLooking up master (lkid %x)\n",
+			   res->res_first_lkid);
 	else
-		rv = seq_printf(s, "\"  \nInvalid master %d\n",
-				res->res_nodeid);
-	if (rv)
+		seq_printf(s, "\"\nInvalid master %d\n", res->res_nodeid);
+	if (seq_has_overflowed(s))
 		goto out;
 
 	/* Print the LVB: */
 	if (res->res_lvbptr) {
-		seq_printf(s, "LVB: ");
+		seq_puts(s, "LVB: ");
 		for (i = 0; i < lvblen; i++) {
 			if (i == lvblen / 2)
-				seq_printf(s, "\n     ");
+				seq_puts(s, "\n     ");
 			seq_printf(s, "%02x ",
 				   (unsigned char) res->res_lvbptr[i]);
 		}
 		if (rsb_flag(res, RSB_VALNOTVALID))
-			seq_printf(s, " (INVALID)");
-		rv = seq_printf(s, "\n");
-		if (rv)
+			seq_puts(s, " (INVALID)");
+		seq_putc(s, '\n');
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
@@ -125,59 +121,57 @@ static int print_format1(struct dlm_rsb *res, struct seq_file *s)
 	recover_list = !list_empty(&res->res_recover_list);
 
 	if (root_list || recover_list) {
-		rv = seq_printf(s, "Recovery: root %d recover %d flags %lx "
-				"count %d\n", root_list, recover_list,
-			   	res->res_flags, res->res_recover_locks_count);
-		if (rv)
-			goto out;
+		seq_printf(s, "Recovery: root %d recover %d flags %lx count %d\n",
+			   root_list, recover_list,
+			   res->res_flags, res->res_recover_locks_count);
 	}
 
 	/* Print the locks attached to this resource */
-	seq_printf(s, "Granted Queue\n");
+	seq_puts(s, "Granted Queue\n");
 	list_for_each_entry(lkb, &res->res_grantqueue, lkb_statequeue) {
-		rv = print_format1_lock(s, lkb, res);
-		if (rv)
+		print_format1_lock(s, lkb, res);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
-	seq_printf(s, "Conversion Queue\n");
+	seq_puts(s, "Conversion Queue\n");
 	list_for_each_entry(lkb, &res->res_convertqueue, lkb_statequeue) {
-		rv = print_format1_lock(s, lkb, res);
-		if (rv)
+		print_format1_lock(s, lkb, res);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
-	seq_printf(s, "Waiting Queue\n");
+	seq_puts(s, "Waiting Queue\n");
 	list_for_each_entry(lkb, &res->res_waitqueue, lkb_statequeue) {
-		rv = print_format1_lock(s, lkb, res);
-		if (rv)
+		print_format1_lock(s, lkb, res);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	if (list_empty(&res->res_lookup))
 		goto out;
 
-	seq_printf(s, "Lookup Queue\n");
+	seq_puts(s, "Lookup Queue\n");
 	list_for_each_entry(lkb, &res->res_lookup, lkb_rsb_lookup) {
-		rv = seq_printf(s, "%08x %s", lkb->lkb_id,
-				print_lockmode(lkb->lkb_rqmode));
+		seq_printf(s, "%08x %s",
+			   lkb->lkb_id, print_lockmode(lkb->lkb_rqmode));
 		if (lkb->lkb_wait_type)
 			seq_printf(s, " wait_type: %d", lkb->lkb_wait_type);
-		rv = seq_printf(s, "\n");
+		seq_putc(s, '\n');
+		if (seq_has_overflowed(s))
+			goto out;
 	}
  out:
 	unlock_rsb(res);
-	return rv;
 }
 
-static int print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
-			      struct dlm_rsb *r)
+static void print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
+			       struct dlm_rsb *r)
 {
 	u64 xid = 0;
 	u64 us;
-	int rv;
 
-	if (lkb->lkb_flags & DLM_IFL_USER) {
+	if (test_bit(DLM_DFL_USER_BIT, &lkb->lkb_dflags)) {
 		if (lkb->lkb_ua)
 			xid = lkb->lkb_ua->xid;
 	}
@@ -188,103 +182,97 @@ static int print_format2_lock(struct seq_file *s, struct dlm_lkb *lkb,
 	/* id nodeid remid pid xid exflags flags sts grmode rqmode time_us
 	   r_nodeid r_len r_name */
 
-	rv = seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %llu %u %d \"%s\"\n",
-			lkb->lkb_id,
-			lkb->lkb_nodeid,
-			lkb->lkb_remid,
-			lkb->lkb_ownpid,
-			(unsigned long long)xid,
-			lkb->lkb_exflags,
-			lkb->lkb_flags,
-			lkb->lkb_status,
-			lkb->lkb_grmode,
-			lkb->lkb_rqmode,
-			(unsigned long long)us,
-			r->res_nodeid,
-			r->res_length,
-			r->res_name);
-	return rv;
+	seq_printf(s, "%x %d %x %u %llu %x %x %d %d %d %llu %u %d \"%s\"\n",
+		   lkb->lkb_id,
+		   lkb->lkb_nodeid,
+		   lkb->lkb_remid,
+		   lkb->lkb_ownpid,
+		   (unsigned long long)xid,
+		   lkb->lkb_exflags,
+		   dlm_iflags_val(lkb),
+		   lkb->lkb_status,
+		   lkb->lkb_grmode,
+		   lkb->lkb_rqmode,
+		   (unsigned long long)us,
+		   r->res_nodeid,
+		   r->res_length,
+		   r->res_name);
 }
 
-static int print_format2(struct dlm_rsb *r, struct seq_file *s)
+static void print_format2(struct dlm_rsb *r, struct seq_file *s)
 {
 	struct dlm_lkb *lkb;
-	int rv = 0;
 
 	lock_rsb(r);
 
 	list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
-		rv = print_format2_lock(s, lkb, r);
-		if (rv)
+		print_format2_lock(s, lkb, r);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
-		rv = print_format2_lock(s, lkb, r);
-		if (rv)
+		print_format2_lock(s, lkb, r);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
-		rv = print_format2_lock(s, lkb, r);
-		if (rv)
+		print_format2_lock(s, lkb, r);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
  out:
 	unlock_rsb(r);
-	return rv;
 }
 
-static int print_format3_lock(struct seq_file *s, struct dlm_lkb *lkb,
+static void print_format3_lock(struct seq_file *s, struct dlm_lkb *lkb,
 			      int rsb_lookup)
 {
 	u64 xid = 0;
-	int rv;
 
-	if (lkb->lkb_flags & DLM_IFL_USER) {
+	if (test_bit(DLM_DFL_USER_BIT, &lkb->lkb_dflags)) {
 		if (lkb->lkb_ua)
 			xid = lkb->lkb_ua->xid;
 	}
 
-	rv = seq_printf(s, "lkb %x %d %x %u %llu %x %x %d %d %d %d %d %d %u %llu %llu\n",
-			lkb->lkb_id,
-			lkb->lkb_nodeid,
-			lkb->lkb_remid,
-			lkb->lkb_ownpid,
-			(unsigned long long)xid,
-			lkb->lkb_exflags,
-			lkb->lkb_flags,
-			lkb->lkb_status,
-			lkb->lkb_grmode,
-			lkb->lkb_rqmode,
-			lkb->lkb_last_bast.mode,
-			rsb_lookup,
-			lkb->lkb_wait_type,
-			lkb->lkb_lvbseq,
-			(unsigned long long)ktime_to_ns(lkb->lkb_timestamp),
-			(unsigned long long)ktime_to_ns(lkb->lkb_last_bast_time));
-	return rv;
+	seq_printf(s, "lkb %x %d %x %u %llu %x %x %d %d %d %d %d %d %u %llu %llu\n",
+		   lkb->lkb_id,
+		   lkb->lkb_nodeid,
+		   lkb->lkb_remid,
+		   lkb->lkb_ownpid,
+		   (unsigned long long)xid,
+		   lkb->lkb_exflags,
+		   dlm_iflags_val(lkb),
+		   lkb->lkb_status,
+		   lkb->lkb_grmode,
+		   lkb->lkb_rqmode,
+		   lkb->lkb_last_bast_cb_mode,
+		   rsb_lookup,
+		   lkb->lkb_wait_type,
+		   lkb->lkb_lvbseq,
+		   (unsigned long long)ktime_to_ns(lkb->lkb_timestamp),
+		   (unsigned long long)ktime_to_ns(lkb->lkb_last_bast_time));
 }
 
-static int print_format3(struct dlm_rsb *r, struct seq_file *s)
+static void print_format3(struct dlm_rsb *r, struct seq_file *s)
 {
 	struct dlm_lkb *lkb;
 	int i, lvblen = r->res_ls->ls_lvblen;
 	int print_name = 1;
-	int rv;
 
 	lock_rsb(r);
 
-	rv = seq_printf(s, "rsb %p %d %x %lx %d %d %u %d ",
-			r,
-			r->res_nodeid,
-			r->res_first_lkid,
-			r->res_flags,
-			!list_empty(&r->res_root_list),
-			!list_empty(&r->res_recover_list),
-			r->res_recover_locks_count,
-			r->res_length);
-	if (rv)
+	seq_printf(s, "rsb %p %d %x %lx %d %d %u %d ",
+		   r,
+		   r->res_nodeid,
+		   r->res_first_lkid,
+		   r->res_flags,
+		   !list_empty(&r->res_root_list),
+		   !list_empty(&r->res_recover_list),
+		   r->res_recover_locks_count,
+		   r->res_length);
+	if (seq_has_overflowed(s))
 		goto out;
 
 	for (i = 0; i < r->res_length; i++) {
@@ -292,7 +280,7 @@ static int print_format3(struct dlm_rsb *r, struct seq_file *s)
 			print_name = 0;
 	}
 
-	seq_printf(s, "%s", print_name ? "str " : "hex");
+	seq_puts(s, print_name ? "str " : "hex");
 
 	for (i = 0; i < r->res_length; i++) {
 		if (print_name)
@@ -300,8 +288,8 @@ static int print_format3(struct dlm_rsb *r, struct seq_file *s)
 		else
 			seq_printf(s, " %02x", (unsigned char)r->res_name[i]);
 	}
-	rv = seq_printf(s, "\n");
-	if (rv)
+	seq_putc(s, '\n');
+	if (seq_has_overflowed(s))
 		goto out;
 
 	if (!r->res_lvbptr)
@@ -311,65 +299,62 @@ static int print_format3(struct dlm_rsb *r, struct seq_file *s)
 
 	for (i = 0; i < lvblen; i++)
 		seq_printf(s, " %02x", (unsigned char)r->res_lvbptr[i]);
-	rv = seq_printf(s, "\n");
-	if (rv)
+	seq_putc(s, '\n');
+	if (seq_has_overflowed(s))
 		goto out;
 
  do_locks:
 	list_for_each_entry(lkb, &r->res_grantqueue, lkb_statequeue) {
-		rv = print_format3_lock(s, lkb, 0);
-		if (rv)
+		print_format3_lock(s, lkb, 0);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_convertqueue, lkb_statequeue) {
-		rv = print_format3_lock(s, lkb, 0);
-		if (rv)
+		print_format3_lock(s, lkb, 0);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_waitqueue, lkb_statequeue) {
-		rv = print_format3_lock(s, lkb, 0);
-		if (rv)
+		print_format3_lock(s, lkb, 0);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
 
 	list_for_each_entry(lkb, &r->res_lookup, lkb_rsb_lookup) {
-		rv = print_format3_lock(s, lkb, 1);
-		if (rv)
+		print_format3_lock(s, lkb, 1);
+		if (seq_has_overflowed(s))
 			goto out;
 	}
  out:
 	unlock_rsb(r);
-	return rv;
 }
 
-static int print_format4(struct dlm_rsb *r, struct seq_file *s)
+static void print_format4(struct dlm_rsb *r, struct seq_file *s)
 {
 	int our_nodeid = dlm_our_nodeid();
 	int print_name = 1;
-	int i, rv;
+	int i;
 
 	lock_rsb(r);
 
-	rv = seq_printf(s, "rsb %p %d %d %d %d %lu %lx %d ",
-			r,
-			r->res_nodeid,
-			r->res_master_nodeid,
-			r->res_dir_nodeid,
-			our_nodeid,
-			r->res_toss_time,
-			r->res_flags,
-			r->res_length);
-	if (rv)
-		goto out;
+	seq_printf(s, "rsb %p %d %d %d %d %lu %lx %d ",
+		   r,
+		   r->res_nodeid,
+		   r->res_master_nodeid,
+		   r->res_dir_nodeid,
+		   our_nodeid,
+		   r->res_toss_time,
+		   r->res_flags,
+		   r->res_length);
 
 	for (i = 0; i < r->res_length; i++) {
 		if (!isascii(r->res_name[i]) || !isprint(r->res_name[i]))
 			print_name = 0;
 	}
 
-	seq_printf(s, "%s", print_name ? "str " : "hex");
+	seq_puts(s, print_name ? "str " : "hex");
 
 	for (i = 0; i < r->res_length; i++) {
 		if (print_name)
@@ -377,220 +362,79 @@ static int print_format4(struct dlm_rsb *r, struct seq_file *s)
 		else
 			seq_printf(s, " %02x", (unsigned char)r->res_name[i]);
 	}
-	rv = seq_printf(s, "\n");
- out:
+	seq_putc(s, '\n');
 	unlock_rsb(r);
-	return rv;
 }
 
-struct rsbtbl_iter {
-	struct dlm_rsb *rsb;
-	unsigned bucket;
-	int format;
-	int header;
-};
+static const struct seq_operations format1_seq_ops;
+static const struct seq_operations format2_seq_ops;
+static const struct seq_operations format3_seq_ops;
+static const struct seq_operations format4_seq_ops;
 
-/* seq_printf returns -1 if the buffer is full, and 0 otherwise.
-   If the buffer is full, seq_printf can be called again, but it
-   does nothing and just returns -1.  So, the these printing routines
-   periodically check the return value to avoid wasting too much time
-   trying to print to a full buffer. */
+/*
+ * If the buffer is full, seq_printf can be called again, but it
+ * does nothing.  So, the these printing routines periodically check
+ * seq_has_overflowed to avoid wasting too much time trying to print to
+ * a full buffer.
+ */
 
 static int table_seq_show(struct seq_file *seq, void *iter_ptr)
 {
-	struct rsbtbl_iter *ri = iter_ptr;
-	int rv = 0;
-
-	switch (ri->format) {
-	case 1:
-		rv = print_format1(ri->rsb, seq);
-		break;
-	case 2:
-		if (ri->header) {
-			seq_printf(seq, "id nodeid remid pid xid exflags "
-					"flags sts grmode rqmode time_ms "
-					"r_nodeid r_len r_name\n");
-			ri->header = 0;
-		}
-		rv = print_format2(ri->rsb, seq);
-		break;
-	case 3:
-		if (ri->header) {
-			seq_printf(seq, "version rsb 1.1 lvb 1.1 lkb 1.1\n");
-			ri->header = 0;
-		}
-		rv = print_format3(ri->rsb, seq);
-		break;
-	case 4:
-		if (ri->header) {
-			seq_printf(seq, "version 4 rsb 2\n");
-			ri->header = 0;
-		}
-		rv = print_format4(ri->rsb, seq);
-		break;
-	}
+	struct dlm_rsb *rsb = list_entry(iter_ptr, struct dlm_rsb, res_slow_list);
 
-	return rv;
-}
+	if (seq->op == &format1_seq_ops)
+		print_format1(rsb, seq);
+	else if (seq->op == &format2_seq_ops)
+		print_format2(rsb, seq);
+	else if (seq->op == &format3_seq_ops)
+		print_format3(rsb, seq);
+	else if (seq->op == &format4_seq_ops)
+		print_format4(rsb, seq);
 
-static const struct seq_operations format1_seq_ops;
-static const struct seq_operations format2_seq_ops;
-static const struct seq_operations format3_seq_ops;
-static const struct seq_operations format4_seq_ops;
+	return 0;
+}
 
 static void *table_seq_start(struct seq_file *seq, loff_t *pos)
 {
-	struct rb_root *tree;
-	struct rb_node *node;
 	struct dlm_ls *ls = seq->private;
-	struct rsbtbl_iter *ri;
-	struct dlm_rsb *r;
-	loff_t n = *pos;
-	unsigned bucket, entry;
-	int toss = (seq->op == &format4_seq_ops);
-
-	bucket = n >> 32;
-	entry = n & ((1LL << 32) - 1);
-
-	if (bucket >= ls->ls_rsbtbl_size)
-		return NULL;
-
-	ri = kzalloc(sizeof(struct rsbtbl_iter), GFP_NOFS);
-	if (!ri)
-		return NULL;
-	if (n == 0)
-		ri->header = 1;
-	if (seq->op == &format1_seq_ops)
-		ri->format = 1;
-	if (seq->op == &format2_seq_ops)
-		ri->format = 2;
-	if (seq->op == &format3_seq_ops)
-		ri->format = 3;
-	if (seq->op == &format4_seq_ops)
-		ri->format = 4;
-
-	tree = toss ? &ls->ls_rsbtbl[bucket].toss : &ls->ls_rsbtbl[bucket].keep;
-
-	spin_lock(&ls->ls_rsbtbl[bucket].lock);
-	if (!RB_EMPTY_ROOT(tree)) {
-		for (node = rb_first(tree); node; node = rb_next(node)) {
-			r = rb_entry(node, struct dlm_rsb, res_hashnode);
-			if (!entry--) {
-				dlm_hold_rsb(r);
-				ri->rsb = r;
-				ri->bucket = bucket;
-				spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-				return ri;
-			}
-		}
+	struct list_head *list;
+
+	if (!*pos) {
+		if (seq->op == &format2_seq_ops)
+			seq_puts(seq, "id nodeid remid pid xid exflags flags sts grmode rqmode time_ms r_nodeid r_len r_name\n");
+		else if (seq->op == &format3_seq_ops)
+			seq_puts(seq, "rsb ptr nodeid first_lkid flags !root_list_empty !recover_list_empty recover_locks_count len\n");
+		else if (seq->op == &format4_seq_ops)
+			seq_puts(seq, "rsb ptr nodeid master_nodeid dir_nodeid our_nodeid toss_time flags len str|hex name\n");
 	}
-	spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-
-	/*
-	 * move to the first rsb in the next non-empty bucket
-	 */
 
-	/* zero the entry */
-	n &= ~((1LL << 32) - 1);
-
-	while (1) {
-		bucket++;
-		n += 1LL << 32;
+	if (seq->op == &format4_seq_ops)
+		list = &ls->ls_slow_inactive;
+	else
+		list = &ls->ls_slow_active;
 
-		if (bucket >= ls->ls_rsbtbl_size) {
-			kfree(ri);
-			return NULL;
-		}
-		tree = toss ? &ls->ls_rsbtbl[bucket].toss : &ls->ls_rsbtbl[bucket].keep;
-
-		spin_lock(&ls->ls_rsbtbl[bucket].lock);
-		if (!RB_EMPTY_ROOT(tree)) {
-			node = rb_first(tree);
-			r = rb_entry(node, struct dlm_rsb, res_hashnode);
-			dlm_hold_rsb(r);
-			ri->rsb = r;
-			ri->bucket = bucket;
-			spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-			*pos = n;
-			return ri;
-		}
-		spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-	}
+	read_lock_bh(&ls->ls_rsbtbl_lock);
+	return seq_list_start(list, *pos);
 }
 
 static void *table_seq_next(struct seq_file *seq, void *iter_ptr, loff_t *pos)
 {
 	struct dlm_ls *ls = seq->private;
-	struct rsbtbl_iter *ri = iter_ptr;
-	struct rb_root *tree;
-	struct rb_node *next;
-	struct dlm_rsb *r, *rp;
-	loff_t n = *pos;
-	unsigned bucket;
-	int toss = (seq->op == &format4_seq_ops);
-
-	bucket = n >> 32;
-
-	/*
-	 * move to the next rsb in the same bucket
-	 */
-
-	spin_lock(&ls->ls_rsbtbl[bucket].lock);
-	rp = ri->rsb;
-	next = rb_next(&rp->res_hashnode);
-
-	if (next) {
-		r = rb_entry(next, struct dlm_rsb, res_hashnode);
-		dlm_hold_rsb(r);
-		ri->rsb = r;
-		spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-		dlm_put_rsb(rp);
-		++*pos;
-		return ri;
-	}
-	spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-	dlm_put_rsb(rp);
+	struct list_head *list;
 
-	/*
-	 * move to the first rsb in the next non-empty bucket
-	 */
-
-	/* zero the entry */
-	n &= ~((1LL << 32) - 1);
-
-	while (1) {
-		bucket++;
-		n += 1LL << 32;
+	if (seq->op == &format4_seq_ops)
+		list = &ls->ls_slow_inactive;
+	else
+		list = &ls->ls_slow_active;
 
-		if (bucket >= ls->ls_rsbtbl_size) {
-			kfree(ri);
-			return NULL;
-		}
-		tree = toss ? &ls->ls_rsbtbl[bucket].toss : &ls->ls_rsbtbl[bucket].keep;
-
-		spin_lock(&ls->ls_rsbtbl[bucket].lock);
-		if (!RB_EMPTY_ROOT(tree)) {
-			next = rb_first(tree);
-			r = rb_entry(next, struct dlm_rsb, res_hashnode);
-			dlm_hold_rsb(r);
-			ri->rsb = r;
-			ri->bucket = bucket;
-			spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-			*pos = n;
-			return ri;
-		}
-		spin_unlock(&ls->ls_rsbtbl[bucket].lock);
-	}
+	return seq_list_next(iter_ptr, list, pos);
 }
 
 static void table_seq_stop(struct seq_file *seq, void *iter_ptr)
 {
-	struct rsbtbl_iter *ri = iter_ptr;
+	struct dlm_ls *ls = seq->private;
 
-	if (ri) {
-		dlm_put_rsb(ri->rsb);
-		kfree(ri);
-	}
+	read_unlock_bh(&ls->ls_rsbtbl_lock);
 }
 
 static const struct seq_operations format1_seq_ops = {
@@ -626,20 +470,83 @@ static const struct file_operations format2_fops;
 static const struct file_operations format3_fops;
 static const struct file_operations format4_fops;
 
-static int table_open(struct inode *inode, struct file *file)
+static int table_open1(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq;
+	int ret;
+
+	ret = seq_open(file, &format1_seq_ops);
+	if (ret)
+		return ret;
+
+	seq = file->private_data;
+	seq->private = inode->i_private; /* the dlm_ls */
+	return 0;
+}
+
+static int table_open2(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq;
+	int ret;
+
+	ret = seq_open(file, &format2_seq_ops);
+	if (ret)
+		return ret;
+
+	seq = file->private_data;
+	seq->private = inode->i_private; /* the dlm_ls */
+	return 0;
+}
+
+static ssize_t table_write2(struct file *file, const char __user *user_buf,
+			    size_t count, loff_t *ppos)
+{
+	struct seq_file *seq = file->private_data;
+	int n, len, lkb_nodeid, lkb_status, error;
+	char name[DLM_RESNAME_MAXLEN + 1] = {};
+	struct dlm_ls *ls = seq->private;
+	unsigned int lkb_flags;
+	char buf[256] = {};
+	uint32_t lkb_id;
+
+	if (copy_from_user(buf, user_buf,
+			   min_t(size_t, sizeof(buf) - 1, count)))
+		return -EFAULT;
+
+	n = sscanf(buf, "%x %" __stringify(DLM_RESNAME_MAXLEN) "s %x %d %d",
+		   &lkb_id, name, &lkb_flags, &lkb_nodeid, &lkb_status);
+	if (n != 5)
+		return -EINVAL;
+
+	len = strnlen(name, DLM_RESNAME_MAXLEN);
+	error = dlm_debug_add_lkb(ls, lkb_id, name, len, lkb_flags,
+				  lkb_nodeid, lkb_status);
+	if (error)
+		return error;
+
+	return count;
+}
+
+static int table_open3(struct inode *inode, struct file *file)
 {
 	struct seq_file *seq;
-	int ret = -1;
+	int ret;
 
-	if (file->f_op == &format1_fops)
-		ret = seq_open(file, &format1_seq_ops);
-	else if (file->f_op == &format2_fops)
-		ret = seq_open(file, &format2_seq_ops);
-	else if (file->f_op == &format3_fops)
-		ret = seq_open(file, &format3_seq_ops);
-	else if (file->f_op == &format4_fops)
-		ret = seq_open(file, &format4_seq_ops);
+	ret = seq_open(file, &format3_seq_ops);
+	if (ret)
+		return ret;
 
+	seq = file->private_data;
+	seq->private = inode->i_private; /* the dlm_ls */
+	return 0;
+}
+
+static int table_open4(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq;
+	int ret;
+
+	ret = seq_open(file, &format4_seq_ops);
 	if (ret)
 		return ret;
 
@@ -650,7 +557,7 @@ static int table_open(struct inode *inode, struct file *file)
 
 static const struct file_operations format1_fops = {
 	.owner   = THIS_MODULE,
-	.open    = table_open,
+	.open    = table_open1,
 	.read    = seq_read,
 	.llseek  = seq_lseek,
 	.release = seq_release
@@ -658,15 +565,16 @@ static const struct file_operations format1_fops = {
 
 static const struct file_operations format2_fops = {
 	.owner   = THIS_MODULE,
-	.open    = table_open,
+	.open    = table_open2,
 	.read    = seq_read,
+	.write   = table_write2,
 	.llseek  = seq_lseek,
 	.release = seq_release
 };
 
 static const struct file_operations format3_fops = {
 	.owner   = THIS_MODULE,
-	.open    = table_open,
+	.open    = table_open3,
 	.read    = seq_read,
 	.llseek  = seq_lseek,
 	.release = seq_release
@@ -674,7 +582,7 @@ static const struct file_operations format3_fops = {
 
 static const struct file_operations format4_fops = {
 	.owner   = THIS_MODULE,
-	.open    = table_open,
+	.open    = table_open4,
 	.read    = seq_read,
 	.llseek  = seq_lseek,
 	.release = seq_release
@@ -691,7 +599,13 @@ static ssize_t waiters_read(struct file *file, char __user *userbuf,
 	size_t len = DLM_DEBUG_BUF_LEN, pos = 0, ret, rv;
 
 	mutex_lock(&debug_buf_lock);
-	mutex_lock(&ls->ls_waiters_mutex);
+	ret = dlm_lock_recovery_try(ls);
+	if (!ret) {
+		rv = -EAGAIN;
+		goto out;
+	}
+
+	spin_lock_bh(&ls->ls_waiters_lock);
 	memset(debug_buf, 0, sizeof(debug_buf));
 
 	list_for_each_entry(lkb, &ls->ls_waiters, lkb_wait_reply) {
@@ -702,37 +616,153 @@ static ssize_t waiters_read(struct file *file, char __user *userbuf,
 			break;
 		pos += ret;
 	}
-	mutex_unlock(&ls->ls_waiters_mutex);
+	spin_unlock_bh(&ls->ls_waiters_lock);
+	dlm_unlock_recovery(ls);
 
 	rv = simple_read_from_buffer(userbuf, count, ppos, debug_buf, pos);
+out:
 	mutex_unlock(&debug_buf_lock);
 	return rv;
 }
 
+static ssize_t waiters_write(struct file *file, const char __user *user_buf,
+			     size_t count, loff_t *ppos)
+{
+	struct dlm_ls *ls = file->private_data;
+	int mstype, to_nodeid;
+	char buf[128] = {};
+	uint32_t lkb_id;
+	int n, error;
+
+	if (copy_from_user(buf, user_buf,
+			   min_t(size_t, sizeof(buf) - 1, count)))
+		return -EFAULT;
+
+	n = sscanf(buf, "%x %d %d", &lkb_id, &mstype, &to_nodeid);
+	if (n != 3)
+		return -EINVAL;
+
+	error = dlm_lock_recovery_try(ls);
+	if (!error)
+		return -EAGAIN;
+
+	error = dlm_debug_add_lkb_to_waiters(ls, lkb_id, mstype, to_nodeid);
+	dlm_unlock_recovery(ls);
+	if (error)
+		return error;
+
+	return count;
+}
+
 static const struct file_operations waiters_fops = {
 	.owner   = THIS_MODULE,
 	.open    = simple_open,
 	.read    = waiters_read,
+	.write   = waiters_write,
 	.llseek  = default_llseek,
 };
 
 void dlm_delete_debug_file(struct dlm_ls *ls)
 {
-	if (ls->ls_debug_rsb_dentry)
-		debugfs_remove(ls->ls_debug_rsb_dentry);
-	if (ls->ls_debug_waiters_dentry)
-		debugfs_remove(ls->ls_debug_waiters_dentry);
-	if (ls->ls_debug_locks_dentry)
-		debugfs_remove(ls->ls_debug_locks_dentry);
-	if (ls->ls_debug_all_dentry)
-		debugfs_remove(ls->ls_debug_all_dentry);
-	if (ls->ls_debug_toss_dentry)
-		debugfs_remove(ls->ls_debug_toss_dentry);
+	debugfs_remove(ls->ls_debug_rsb_dentry);
+	debugfs_remove(ls->ls_debug_waiters_dentry);
+	debugfs_remove(ls->ls_debug_locks_dentry);
+	debugfs_remove(ls->ls_debug_all_dentry);
+	debugfs_remove(ls->ls_debug_toss_dentry);
+	debugfs_remove(ls->ls_debug_queued_asts_dentry);
+}
+
+static int dlm_state_show(struct seq_file *file, void *offset)
+{
+	seq_printf(file, "%s\n", dlm_midcomms_state(file->private));
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dlm_state);
+
+static int dlm_flags_show(struct seq_file *file, void *offset)
+{
+	seq_printf(file, "%lu\n", dlm_midcomms_flags(file->private));
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dlm_flags);
+
+static int dlm_send_queue_cnt_show(struct seq_file *file, void *offset)
+{
+	seq_printf(file, "%d\n", dlm_midcomms_send_queue_cnt(file->private));
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dlm_send_queue_cnt);
+
+static int dlm_version_show(struct seq_file *file, void *offset)
+{
+	seq_printf(file, "0x%08x\n", dlm_midcomms_version(file->private));
+	return 0;
 }
+DEFINE_SHOW_ATTRIBUTE(dlm_version);
 
-int dlm_create_debug_file(struct dlm_ls *ls)
+static ssize_t dlm_rawmsg_write(struct file *fp, const char __user *user_buf,
+				size_t count, loff_t *ppos)
 {
-	char name[DLM_LOCKSPACE_LEN+8];
+	void *buf;
+	int ret;
+
+	if (count > PAGE_SIZE || count < sizeof(struct dlm_header))
+		return -EINVAL;
+
+	buf = kmalloc(PAGE_SIZE, GFP_NOFS);
+	if (!buf)
+		return -ENOMEM;
+
+	if (copy_from_user(buf, user_buf, count)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	ret = dlm_midcomms_rawmsg_send(fp->private_data, buf, count);
+	if (ret)
+		goto out;
+
+	kfree(buf);
+	return count;
+
+out:
+	kfree(buf);
+	return ret;
+}
+
+static const struct file_operations dlm_rawmsg_fops = {
+	.open	= simple_open,
+	.write	= dlm_rawmsg_write,
+};
+
+void *dlm_create_debug_comms_file(int nodeid, void *data)
+{
+	struct dentry *d_node;
+	char name[256];
+
+	memset(name, 0, sizeof(name));
+	snprintf(name, 256, "%d", nodeid);
+
+	d_node = debugfs_create_dir(name, dlm_comms);
+	debugfs_create_file("state", 0444, d_node, data, &dlm_state_fops);
+	debugfs_create_file("flags", 0444, d_node, data, &dlm_flags_fops);
+	debugfs_create_file("send_queue_count", 0444, d_node, data,
+			    &dlm_send_queue_cnt_fops);
+	debugfs_create_file("version", 0444, d_node, data, &dlm_version_fops);
+	debugfs_create_file("rawmsg", 0200, d_node, data, &dlm_rawmsg_fops);
+
+	return d_node;
+}
+
+void dlm_delete_debug_comms_file(void *ctx)
+{
+	debugfs_remove(ctx);
+}
+
+void dlm_create_debug_file(struct dlm_ls *ls)
+{
+	/* Reserve enough space for the longest file name */
+	char name[DLM_LOCKSPACE_LEN + sizeof("_queued_asts")];
 
 	/* format 1 */
 
@@ -741,71 +771,51 @@ int dlm_create_debug_file(struct dlm_ls *ls)
 						      dlm_root,
 						      ls,
 						      &format1_fops);
-	if (!ls->ls_debug_rsb_dentry)
-		goto fail;
 
 	/* format 2 */
 
-	memset(name, 0, sizeof(name));
-	snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_locks", ls->ls_name);
+	snprintf(name, sizeof(name), "%s_locks", ls->ls_name);
 
 	ls->ls_debug_locks_dentry = debugfs_create_file(name,
-							S_IFREG | S_IRUGO,
+							0644,
 							dlm_root,
 							ls,
 							&format2_fops);
-	if (!ls->ls_debug_locks_dentry)
-		goto fail;
 
 	/* format 3 */
 
-	memset(name, 0, sizeof(name));
-	snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_all", ls->ls_name);
+	snprintf(name, sizeof(name), "%s_all", ls->ls_name);
 
 	ls->ls_debug_all_dentry = debugfs_create_file(name,
 						      S_IFREG | S_IRUGO,
 						      dlm_root,
 						      ls,
 						      &format3_fops);
-	if (!ls->ls_debug_all_dentry)
-		goto fail;
 
 	/* format 4 */
 
-	memset(name, 0, sizeof(name));
-	snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_toss", ls->ls_name);
+	snprintf(name, sizeof(name), "%s_toss", ls->ls_name);
 
 	ls->ls_debug_toss_dentry = debugfs_create_file(name,
 						       S_IFREG | S_IRUGO,
 						       dlm_root,
 						       ls,
 						       &format4_fops);
-	if (!ls->ls_debug_toss_dentry)
-		goto fail;
 
-	memset(name, 0, sizeof(name));
-	snprintf(name, DLM_LOCKSPACE_LEN+8, "%s_waiters", ls->ls_name);
+	snprintf(name, sizeof(name), "%s_waiters", ls->ls_name);
 
 	ls->ls_debug_waiters_dentry = debugfs_create_file(name,
-							  S_IFREG | S_IRUGO,
+							  0644,
 							  dlm_root,
 							  ls,
 							  &waiters_fops);
-	if (!ls->ls_debug_waiters_dentry)
-		goto fail;
-
-	return 0;
-
- fail:
-	dlm_delete_debug_file(ls);
-	return -ENOMEM;
 }
 
-int __init dlm_register_debugfs(void)
+void __init dlm_register_debugfs(void)
 {
 	mutex_init(&debug_buf_lock);
 	dlm_root = debugfs_create_dir("dlm", NULL);
-	return dlm_root ? 0 : -ENOMEM;
+	dlm_comms = debugfs_create_dir("comms", dlm_root);
 }
 
 void dlm_unregister_debugfs(void)