dlm for 6.7

This set of patches has some minor fixes for message handling, some misc
 cleanups, and updates the maintainers entry.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEcGkeEvkvjdvlR90nOBtzx/yAaaoFAmVBETQACgkQOBtzx/yA
 aapeiRAAwveqN80kjxc5lHIuLUZsvMCw8UZlr7nQhB4XDVLQHsfX+rtzPVR3rpDQ
 XTKhM53787XvAx+Qn8wrBGB6i0comB28Dsz91wPSXNrW/nXhbsTLR8XP4D7g0/h3
 /wxJQF/u4IQr/4gtpvafWGB8w1j9iljRKxY90BN+CT1tB0mYgbfGD+RmPwblcm+T
 dlyT+MO83wkTkRwg71PSBrL/81h3IVKpiZiDCJjsLMwjFQT74NEPj/JTdsQptWy5
 lwSqTm8Ye575bKxZfkZpfcoaMZHz2a6p2AZE0wNg1o0PZ0z4o64V1i5iBioymJL0
 oF4flq4/bRQdN/J1jUzRZZOm4QReqBsvlCiPdmq2s8++YMhzE9U4Yl+kiQY3ek6n
 ie7dnPC0XpKQWgc8RNeD4kAK6Qmrus/zIdzzLORGV1f9SINzeH+TsbTPc/h6rSvk
 rbqNJLBlRnX4j9OYzp+kCjcVsrd53q87cb8KoQa/9ekGFyp1svcSKj8XLQLRHTUA
 iN0DZczCu11MrUDg9uyyDJ0cOxXn2/ptswdZeF7SlFAdGmJ0G/L+1aUx1nP/Kgnf
 DaOWRVngjBT9M/Z/aoDDLZx94eqALq/gqevTP8FrA4TopUb67Friy7vZtVAOhSGR
 cVJn0iuzV31sGu+d7O5u0mrnqWcDbHRgv9otGI5HYa5vywgsEvE=
 =PWCW
 -----END PGP SIGNATURE-----

Merge tag 'dlm-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm

Pull dlm updates from David Teigland:
 "This set of patches has some minor fixes for message handling, some
  misc cleanups, and updates the maintainers entry"

* tag 'dlm-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  MAINTAINERS: Update dlm maintainer and web page
  dlm: slow down filling up processing queue
  dlm: fix no ack after final message
  dlm: be sure we reset all nodes at forced shutdown
  dlm: fix remove member after close call
  dlm: fix creating multiple node structures
  fs: dlm: Remove some useless memset()
  fs: dlm: Fix the size of a buffer in dlm_create_debug_file()
  fs: dlm: Simplify buffer size computation in dlm_create_debug_file()

MAINTAINERS

@@ -6172,11 +6172,11 @@ F:	drivers/video/fbdev/udlfb.c
 F:	include/video/udlfb.h
 
 DISTRIBUTED LOCK MANAGER (DLM)
-M:	Christine Caulfield <ccaulfie@redhat.com>
+M:	Alexander Aring <aahringo@redhat.com>
 M:	David Teigland <teigland@redhat.com>
 L:	gfs2@lists.linux.dev
 S:	Supported
-W:	http://sources.redhat.com/cluster/
+W:	https://pagure.io/dlm
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm.git
 F:	fs/dlm/
 

fs/dlm/debug_fs.c

@@ -973,7 +973,8 @@ void dlm_delete_debug_comms_file(void *ctx)
 
 void dlm_create_debug_file(struct dlm_ls *ls)
 {
-	char name[DLM_LOCKSPACE_LEN + 8];
+	/* Reserve enough space for the longest file name */
+	char name[DLM_LOCKSPACE_LEN + sizeof("_queued_asts")];
 
 	/* format 1 */
 
@@ -985,8 +986,7 @@ void dlm_create_debug_file(struct dlm_ls *ls)
 
 	/* format 2 */
 
-	memset(name, 0, sizeof(name));
+	snprintf(name, sizeof(name), "%s_locks", ls->ls_name);
-	snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_locks", ls->ls_name);
 
 	ls->ls_debug_locks_dentry = debugfs_create_file(name,
 							0644,
@@ -996,8 +996,7 @@ void dlm_create_debug_file(struct dlm_ls *ls)
 
 	/* format 3 */
 
-	memset(name, 0, sizeof(name));
+	snprintf(name, sizeof(name), "%s_all", ls->ls_name);
-	snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_all", ls->ls_name);
 
 	ls->ls_debug_all_dentry = debugfs_create_file(name,
 						      S_IFREG | S_IRUGO,
@@ -1007,8 +1006,7 @@ void dlm_create_debug_file(struct dlm_ls *ls)
 
 	/* format 4 */
 
-	memset(name, 0, sizeof(name));
+	snprintf(name, sizeof(name), "%s_toss", ls->ls_name);
-	snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_toss", ls->ls_name);
 
 	ls->ls_debug_toss_dentry = debugfs_create_file(name,
 						       S_IFREG | S_IRUGO,
@@ -1016,8 +1014,7 @@ void dlm_create_debug_file(struct dlm_ls *ls)
 						       ls,
 						       &format4_fops);
 
-	memset(name, 0, sizeof(name));
+	snprintf(name, sizeof(name), "%s_waiters", ls->ls_name);
-	snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_waiters", ls->ls_name);
 
 	ls->ls_debug_waiters_dentry = debugfs_create_file(name,
 							  0644,
@@ -1027,8 +1024,7 @@ void dlm_create_debug_file(struct dlm_ls *ls)
 
 	/* format 5 */
 
-	memset(name, 0, sizeof(name));
+	snprintf(name, sizeof(name), "%s_queued_asts", ls->ls_name);
-	snprintf(name, DLM_LOCKSPACE_LEN + 8, "%s_queued_asts", ls->ls_name);
 
 	ls->ls_debug_queued_asts_dentry = debugfs_create_file(name,
 							      0644,

fs/dlm/lowcomms.c

@@ -63,6 +63,7 @@
 #include "config.h"
 
 #define DLM_SHUTDOWN_WAIT_TIMEOUT msecs_to_jiffies(5000)
+#define DLM_MAX_PROCESS_BUFFERS 24
 #define NEEDED_RMEM (4*1024*1024)
 
 struct connection {
@@ -194,6 +195,7 @@ static const struct dlm_proto_ops *dlm_proto_ops;
 #define DLM_IO_END 1
 #define DLM_IO_EOF 2
 #define DLM_IO_RESCHED 3
+#define DLM_IO_FLUSH 4
 
 static void process_recv_sockets(struct work_struct *work);
 static void process_send_sockets(struct work_struct *work);
@@ -202,6 +204,7 @@ static void process_dlm_messages(struct work_struct *work);
 static DECLARE_WORK(process_work, process_dlm_messages);
 static DEFINE_SPINLOCK(processqueue_lock);
 static bool process_dlm_messages_pending;
+static atomic_t processqueue_count;
 static LIST_HEAD(processqueue);
 
 bool dlm_lowcomms_is_running(void)
@@ -874,6 +877,7 @@ static void process_dlm_messages(struct work_struct *work)
 	}
 
 	list_del(&pentry->list);
+	atomic_dec(&processqueue_count);
 	spin_unlock(&processqueue_lock);
 
 	for (;;) {
@@ -891,6 +895,7 @@ static void process_dlm_messages(struct work_struct *work)
 		}
 
 		list_del(&pentry->list);
+		atomic_dec(&processqueue_count);
 		spin_unlock(&processqueue_lock);
 	}
 }
@@ -962,6 +967,7 @@ again:
 		con->rx_leftover);
 
 	spin_lock(&processqueue_lock);
+	ret = atomic_inc_return(&processqueue_count);
 	list_add_tail(&pentry->list, &processqueue);
 	if (!process_dlm_messages_pending) {
 		process_dlm_messages_pending = true;
@@ -969,6 +975,9 @@ again:
 	}
 	spin_unlock(&processqueue_lock);
 
+	if (ret > DLM_MAX_PROCESS_BUFFERS)
+		return DLM_IO_FLUSH;
+
 	return DLM_IO_SUCCESS;
 }
 
@@ -1503,6 +1512,9 @@ static void process_recv_sockets(struct work_struct *work)
 		wake_up(&con->shutdown_wait);
 		/* CF_RECV_PENDING cleared */
 		break;
+	case DLM_IO_FLUSH:
+		flush_workqueue(process_workqueue);
+		fallthrough;
 	case DLM_IO_RESCHED:
 		cond_resched();
 		queue_work(io_workqueue, &con->rwork);

fs/dlm/midcomms.c

@@ -337,13 +337,21 @@ static struct midcomms_node *nodeid2node(int nodeid)
 
 int dlm_midcomms_addr(int nodeid, struct sockaddr_storage *addr, int len)
 {
-	int ret, r = nodeid_hash(nodeid);
+	int ret, idx, r = nodeid_hash(nodeid);
 	struct midcomms_node *node;
 
 	ret = dlm_lowcomms_addr(nodeid, addr, len);
 	if (ret)
 		return ret;
 
+	idx = srcu_read_lock(&nodes_srcu);
+	node = __find_node(nodeid, r);
+	if (node) {
+		srcu_read_unlock(&nodes_srcu, idx);
+		return 0;
+	}
+	srcu_read_unlock(&nodes_srcu, idx);
+
 	node = kmalloc(sizeof(*node), GFP_NOFS);
 	if (!node)
 		return -ENOMEM;
@@ -1030,15 +1038,15 @@ struct dlm_mhandle *dlm_midcomms_get_mhandle(int nodeid, int len,
 
 		break;
 	case DLM_VERSION_3_2:
+		/* send ack back if necessary */
+		dlm_send_ack_threshold(node, DLM_SEND_ACK_BACK_MSG_THRESHOLD);
+
 		msg = dlm_midcomms_get_msg_3_2(mh, nodeid, len, allocation,
 					       ppc);
 		if (!msg) {
 			dlm_free_mhandle(mh);
 			goto err;
 		}
-
-		/* send ack back if necessary */
-		dlm_send_ack_threshold(node, DLM_SEND_ACK_BACK_MSG_THRESHOLD);
 		break;
 	default:
 		dlm_free_mhandle(mh);
@@ -1260,12 +1268,23 @@ void dlm_midcomms_remove_member(int nodeid)
 
 	idx = srcu_read_lock(&nodes_srcu);
 	node = nodeid2node(nodeid);
-	if (WARN_ON_ONCE(!node)) {
+	/* in case of dlm_midcomms_close() removes node */
+	if (!node) {
 		srcu_read_unlock(&nodes_srcu, idx);
 		return;
 	}
 
 	spin_lock(&node->state_lock);
+	/* case of dlm_midcomms_addr() created node but
+	 * was not added before because dlm_midcomms_close()
+	 * removed the node
+	 */
+	if (!node->users) {
+		spin_unlock(&node->state_lock);
+		srcu_read_unlock(&nodes_srcu, idx);
+		return;
+	}
+
 	node->users--;
 	pr_debug("node %d users dec count %d\n", nodeid, node->users);
 
@@ -1386,10 +1405,16 @@ void dlm_midcomms_shutdown(void)
 			midcomms_shutdown(node);
 		}
 	}
-	srcu_read_unlock(&nodes_srcu, idx);
-	mutex_unlock(&close_lock);
 
 	dlm_lowcomms_shutdown();
+
+	for (i = 0; i < CONN_HASH_SIZE; i++) {
+		hlist_for_each_entry_rcu(node, &node_hash[i], hlist) {
+			midcomms_node_reset(node);
+		}
+	}
+	srcu_read_unlock(&nodes_srcu, idx);
+	mutex_unlock(&close_lock);
 }
 
 int dlm_midcomms_close(int nodeid)