4 files changed, 35 insertions, 1 deletions

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 7fc2addc95a3..a643c84ff1e9 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -80,6 +80,9 @@
 #define SMB_DNS_RESOLVE_INTERVAL_MIN     120
 #define SMB_DNS_RESOLVE_INTERVAL_DEFAULT 600
 
+/* smb multichannel query server interfaces interval in seconds */
+#define SMB_INTERFACE_POLL_INTERVAL	600
+
 /* maximum number of PDUs in one compound */
 #define MAX_COMPOUND 5
 
@@ -1255,6 +1258,7 @@ struct cifs_tcon {
 #ifdef CONFIG_CIFS_DFS_UPCALL
 	struct list_head ulist; /* cache update list */
 #endif
+	struct delayed_work	query_interfaces; /* query interfaces workqueue job */
 };
 
 /*
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 00c4a8aa2649..d59aebefa71c 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -641,6 +641,8 @@ cifs_chan_is_iface_active(struct cifs_ses *ses,
 			  struct TCP_Server_Info *server);
 int
 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server);
+int
+SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon);
 
 void extract_unc_hostname(const char *unc, const char **h, size_t *len);
 int copy_path_name(char *dst, const char *src);
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index d8aae257649f..e666d2643ede 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -145,6 +145,25 @@ requeue_resolve:
 	return rc;
 }
 
+static void smb2_query_server_interfaces(struct work_struct *work)
+{
+	int rc;
+	struct cifs_tcon *tcon = container_of(work,
+					struct cifs_tcon,
+					query_interfaces.work);
+
+	/*
+	 * query server network interfaces, in case they change
+	 */
+	rc = SMB3_request_interfaces(0, tcon);
+	if (rc) {
+		cifs_dbg(FYI, "%s: failed to query server interfaces: %d\n",
+				__func__, rc);
+	}
+
+	queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
+			   (SMB_INTERFACE_POLL_INTERVAL * HZ));
+}
 
 static void cifs_resolve_server(struct work_struct *work)
 {
@@ -2276,6 +2295,9 @@ cifs_put_tcon(struct cifs_tcon *tcon)
 	list_del_init(&tcon->tcon_list);
 	spin_unlock(&cifs_tcp_ses_lock);
 
+	/* cancel polling of interfaces */
+	cancel_delayed_work_sync(&tcon->query_interfaces);
+
 	if (tcon->use_witness) {
 		int rc;
 
@@ -2513,6 +2535,12 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
 	tcon->local_lease = ctx->local_lease;
 	INIT_LIST_HEAD(&tcon->pending_opens);
 
+	/* schedule query interfaces poll */
+	INIT_DELAYED_WORK(&tcon->query_interfaces,
+			  smb2_query_server_interfaces);
+	queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
+			   (SMB_INTERFACE_POLL_INTERVAL * HZ));
+
 	spin_lock(&cifs_tcp_ses_lock);
 	list_add(&tcon->tcon_list, &ses->tcon_list);
 	spin_unlock(&cifs_tcp_ses_lock);
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index db4ccf1d235e..8802995b2d3d 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -671,7 +671,7 @@ out:
 	return rc;
 }
 
-static int
+int
 SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon)
 {
 	int rc;