smb: client: set interface for primary channelmultichannel-fixes-v2

On multichannel mounts, 2 sockets are created for the primary channel,
as the interface it's connected to is received and parsed/added again.

So compare ifaces IP with primary channel server IP (server->dstaddr)
and assign the matching iface to ses->chans[0].iface.

Add a ->is_primary flag to cifs_server_iface to allow skipping session
setup on the primary channel, and for pretty-printing on cifs_debug.c
as well.

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>

4 files changed, 90 insertions, 75 deletions

diff --git a/fs/smb/client/cifs_debug.c b/fs/smb/client/cifs_debug.c
index 0c2acc4e2cbb..34166040569c 100644
--- a/fs/smb/client/cifs_debug.c
+++ b/fs/smb/client/cifs_debug.c
@@ -212,22 +212,16 @@ static inline const char *smb_speed_to_str(size_t bps)
 static void
 cifs_dump_iface(struct seq_file *m, struct cifs_server_iface *iface)
 {
-	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
-	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
-
 	seq_printf(m, "\tSpeed: %s\n", smb_speed_to_str(iface->speed));
 	seq_puts(m, "\t\tCapabilities: ");
 	if (iface->rdma_capable)
-		seq_puts(m, "rdma ");
+		seq_puts(m, "RDMA ");
 	if (iface->rss_capable)
-		seq_puts(m, "rss ");
+		seq_puts(m, "RSS ");
 	if (!iface->rdma_capable && !iface->rss_capable)
-		seq_puts(m, "None");
+		seq_puts(m, "NONE");
 	seq_putc(m, '\n');
-	if (iface->sockaddr.ss_family == AF_INET)
-		seq_printf(m, "\t\tIPv4: %pI4\n", &ipv4->sin_addr);
-	else if (iface->sockaddr.ss_family == AF_INET6)
-		seq_printf(m, "\t\tIPv6: %pI6\n", &ipv6->sin6_addr);
+	seq_printf(m, "\t\tIP: %pIS\n", (struct sockaddr *)&iface->sockaddr);
 	if (!iface->is_active)
 		seq_puts(m, "\t\t[for-cleanup]\n");
 }
@@ -602,7 +596,8 @@ skip_rdma:
 					   iface->num_channels);
 
 				if (is_ses_using_iface(ses, iface))
-					seq_puts(m, "\t\t[CONNECTED]\n");
+					seq_printf(m, "\t\t[CONNECTED]%s\n",
+						   iface->is_primary ? " (PRIMARY)" : "");
 			}
 			spin_unlock(&server->iface_lock);
 
diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index 8631f3b9eaf7..282684316b87 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -1083,6 +1083,7 @@ struct cifs_server_iface {
 	unsigned int rdma_capable : 1;
 	unsigned int rss_capable : 1;
 	unsigned int is_active : 1; /* unset if non existent */
+	unsigned int is_primary : 1;
 	struct sockaddr_storage sockaddr;
 };
 
diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c
index af39c819822f..5c2725eee933 100644
--- a/fs/smb/client/sess.c
+++ b/fs/smb/client/sess.c
@@ -170,8 +170,6 @@ static int try_adding_channels(struct cifs_ses *ses, struct list_head *ifaces)
 	spin_unlock(&pserver->iface_lock);
 
 	list_for_each_entry_safe(iface, niface, ifaces, iface_head) {
-		rc = 0;
-
 		/* do not mix rdma and non-rdma interfaces */
 		if (iface->rdma_capable != ses->server->rdma)
 			continue;
@@ -185,7 +183,15 @@ static int try_adding_channels(struct cifs_ses *ses, struct list_head *ifaces)
 		if (iface->weight_fulfilled >= weight)
 			continue;
 
-		rc = cifs_ses_add_channel(ses, iface);
+		rc = 0;
+		if (!iface->is_primary) {
+			rc = cifs_ses_add_channel(ses, iface);
+		} else {
+			spin_lock(&ses->chan_lock);
+			ses->chans[0].iface = iface;
+			spin_unlock(&ses->chan_lock);
+		}
+
 		if (!rc) {
 			cifs_info("successfully opened new channel on iface:%pIS\n", &iface->sockaddr);
 			iface->is_active = 1;
@@ -195,7 +201,7 @@ static int try_adding_channels(struct cifs_ses *ses, struct list_head *ifaces)
 
 			spin_lock(&pserver->iface_lock);
 			pserver->iface_count++;
-			list_move(&iface->iface_head, &pserver->iface_list);
+			list_move_tail(&iface->iface_head, &pserver->iface_list);
 			pserver->iface_last_update = jiffies;
 			spin_unlock(&pserver->iface_lock);
 
diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index f3efafa23fa4..827cdec61b12 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -593,9 +593,12 @@ static int __iface_cmp(struct cifs_server_iface *a, struct cifs_server_iface *b)
 		return -1;
 	if (a->rdma_capable == b->rdma_capable) {
 		if (a->rss_capable == b->rss_capable) {
-			if (a->speed == b->speed)
-				return cifs_ipaddr_cmp((struct sockaddr *)&a->sockaddr,
-						       (struct sockaddr *)&b->sockaddr);
+			if (a->speed == b->speed) {
+				if (cifs_ipaddr_cmp((struct sockaddr *)&a->sockaddr,
+						    (struct sockaddr *)&b->sockaddr))
+					return -1;
+				return 0;
+			}
 			if (a->speed > b->speed)
 				return -1;
 			return 1;
@@ -623,17 +626,70 @@ static inline bool ifaces_need_update(unsigned long last_update)
 		time_before(jiffies, last_update + (SMB_INTERFACE_POLL_INTERVAL * HZ)));
 }
 
-static int
-parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf, size_t buf_len,
-			struct TCP_Server_Info *pserver, struct list_head *ifaces)
+static inline bool check_iface(struct network_interface_info_ioctl_rsp *info, bool server_rdma,
+			       struct cifs_server_iface *tmp)
 {
-	struct network_interface_info_ioctl_rsp *p;
 	struct sockaddr_in *addr4;
 	struct sockaddr_in6 *addr6;
 	struct iface_info_ipv4 *p4;
 	struct iface_info_ipv6 *p6;
-	struct cifs_server_iface *info = NULL, *iface = NULL, *niface = NULL;
-	struct cifs_server_iface tmp_iface;
+
+	memset(tmp, 0, sizeof(*tmp));
+
+	/* default to 1Gbps when link speed is unset */
+	tmp->speed = le64_to_cpu(info->LinkSpeed) ?: 1000000000;
+	tmp->rdma_capable = le32_to_cpu(info->Capability & RDMA_CAPABLE) ? 1 : 0;
+	tmp->rss_capable = le32_to_cpu(info->Capability & RSS_CAPABLE) ? 1 : 0;
+
+	if (!tmp->rss_capable)
+		return false;
+
+	if (tmp->rdma_capable != server_rdma)
+		return false;
+
+	/*
+	 * The kernel and wire socket structures have the same
+	 * layout and use network byte order but make the
+	 * conversion explicit in case either one changes.
+	 */
+	if (info->Family == INTERNETWORK) {
+		addr4 = (struct sockaddr_in *)&tmp->sockaddr;
+		p4 = (struct iface_info_ipv4 *)info->Buffer;
+		addr4->sin_family = AF_INET;
+		memcpy(&addr4->sin_addr, &p4->IPv4Address, 4);
+
+		/* [MS-SMB2] 2.2.32.5.1.1 Clients MUST ignore these */
+		addr4->sin_port = cpu_to_be16(CIFS_PORT);
+
+		cifs_dbg(FYI, "%s: ipv4 %pI4\n", __func__, &addr4->sin_addr);
+		return true;
+	}
+
+	if (info->Family == INTERNETWORKV6) {
+		addr6 =	(struct sockaddr_in6 *)&tmp->sockaddr;
+		p6 = (struct iface_info_ipv6 *)info->Buffer;
+		addr6->sin6_family = AF_INET6;
+		memcpy(&addr6->sin6_addr, &p6->IPv6Address, 16);
+
+		/* [MS-SMB2] 2.2.32.5.1.2 Clients MUST ignore these */
+		addr6->sin6_flowinfo = 0;
+		addr6->sin6_scope_id = 0;
+		addr6->sin6_port = cpu_to_be16(CIFS_PORT);
+
+		cifs_dbg(FYI, "%s: ipv6 %pI6\n", __func__, &addr6->sin6_addr);
+		return true;
+	}
+
+	cifs_dbg(VFS, "%s: skipping unsupported socket family\n", __func__);
+	return false;
+}
+
+static int
+parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf, size_t buf_len,
+			struct TCP_Server_Info *pserver, struct list_head *ifaces)
+{
+	struct network_interface_info_ioctl_rsp *p;
+	struct cifs_server_iface *info = NULL, *iface = NULL, *niface = NULL, tmp_iface = {};
 	ssize_t bytes_left;
 	size_t next = 0;
 	int nb_iface = 0;
@@ -653,57 +709,9 @@ parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf, size_t buf
 	}
 
 	while (bytes_left >= (ssize_t)sizeof(*p)) {
-		memset(&tmp_iface, 0, sizeof(tmp_iface));
-		/* default to 1Gbps when link speed is unset */
-		tmp_iface.speed = le64_to_cpu(p->LinkSpeed) ?: 1000000000;
-		tmp_iface.rdma_capable = le32_to_cpu(p->Capability & RDMA_CAPABLE) ? 1 : 0;
-		tmp_iface.rss_capable = le32_to_cpu(p->Capability & RSS_CAPABLE) ? 1 : 0;
-
-		if (!tmp_iface.rss_capable)
-			goto next_iface;
-
-		if (tmp_iface.rdma_capable != pserver->rdma)
+		if (!check_iface(p, pserver->rdma, &tmp_iface))
 			goto next_iface;
 
-		switch (p->Family) {
-		/*
-		 * The kernel and wire socket structures have the same
-		 * layout and use network byte order but make the
-		 * conversion explicit in case either one changes.
-		 */
-		case INTERNETWORK:
-			addr4 = (struct sockaddr_in *)&tmp_iface.sockaddr;
-			p4 = (struct iface_info_ipv4 *)p->Buffer;
-			addr4->sin_family = AF_INET;
-			memcpy(&addr4->sin_addr, &p4->IPv4Address, 4);
-
-			/* [MS-SMB2] 2.2.32.5.1.1 Clients MUST ignore these */
-			addr4->sin_port = cpu_to_be16(CIFS_PORT);
-
-			cifs_dbg(FYI, "%s: ipv4 %pI4\n", __func__,
-				 &addr4->sin_addr);
-			break;
-		case INTERNETWORKV6:
-			addr6 =	(struct sockaddr_in6 *)&tmp_iface.sockaddr;
-			p6 = (struct iface_info_ipv6 *)p->Buffer;
-			addr6->sin6_family = AF_INET6;
-			memcpy(&addr6->sin6_addr, &p6->IPv6Address, 16);
-
-			/* [MS-SMB2] 2.2.32.5.1.2 Clients MUST ignore these */
-			addr6->sin6_flowinfo = 0;
-			addr6->sin6_scope_id = 0;
-			addr6->sin6_port = cpu_to_be16(CIFS_PORT);
-
-			cifs_dbg(FYI, "%s: ipv6 %pI6\n", __func__,
-				 &addr6->sin6_addr);
-			break;
-		default:
-			cifs_dbg(VFS,
-				 "%s: skipping unsupported socket family\n",
-				 __func__);
-			goto next_iface;
-		}
-
 		/*
 		 * iface_list is sorted by speed.
 		 * Check if the new interface exists in that list.
@@ -737,13 +745,18 @@ parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf, size_t buf
 		/* add this new entry to the list */
 		kref_init(&info->refcount);
 
-		cifs_dbg(FYI, "%s: adding iface[%zu]: %pIS\n", __func__, pserver->iface_count,
-			 &info->sockaddr);
+		cifs_dbg(FYI, "%s: adding iface: %pIS\n", __func__, &info->sockaddr);
 		cifs_dbg(FYI, "%s: speed %zu bps\n", __func__, info->speed);
 		cifs_dbg(FYI, "%s: capabilities 0x%08x\n", __func__,
 			 le32_to_cpu(p->Capability));
 
+		/* mark primary channel to avoid duplicate sockets */
+		if (unlikely(!cifs_ipaddr_cmp((struct sockaddr *)&info->sockaddr,
+					      (struct sockaddr *)&pserver->dstaddr)))
+			info->is_primary = 1;
+
 		list_add_tail(&info->iface_head, ifaces);
+
 next_iface:
 		nb_iface++;
 		next = le32_to_cpu(p->Next);