fs: dlm: set skb mark per peer socket

This patch adds support to set the skb mark value for the DLM tcp and
sctp socket per peer. The mark value will be offered as per comm value
of configfs. At creation time of the peer socket it will be set as
socket option.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

fs/dlm/config.c

@@ -200,6 +200,7 @@ enum {
 	COMM_ATTR_LOCAL,
 	COMM_ATTR_ADDR,
 	COMM_ATTR_ADDR_LIST,
+	COMM_ATTR_MARK,
 };
 
 enum {
@@ -232,6 +233,7 @@ struct dlm_comm {
 	int nodeid;
 	int local;
 	int addr_count;
+	unsigned int mark;
 	struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
 };
 
@@ -469,6 +471,7 @@ static struct config_item *make_comm(struct config_group *g, const char *name)
 	cm->nodeid = -1;
 	cm->local = 0;
 	cm->addr_count = 0;
+	cm->mark = 0;
 	return &cm->item;
 }
 
@@ -664,8 +667,28 @@ static ssize_t comm_addr_list_show(struct config_item *item, char *buf)
 	return 4096 - allowance;
 }
 
+static ssize_t comm_mark_show(struct config_item *item, char *buf)
+{
+	return sprintf(buf, "%u\n", config_item_to_comm(item)->mark);
+}
+
+static ssize_t comm_mark_store(struct config_item *item, const char *buf,
+			       size_t len)
+{
+	unsigned int mark;
+	int rc;
+
+	rc = kstrtouint(buf, 0, &mark);
+	if (rc)
+		return rc;
+
+	config_item_to_comm(item)->mark = mark;
+	return len;
+}
+
 CONFIGFS_ATTR(comm_, nodeid);
 CONFIGFS_ATTR(comm_, local);
+CONFIGFS_ATTR(comm_, mark);
 CONFIGFS_ATTR_WO(comm_, addr);
 CONFIGFS_ATTR_RO(comm_, addr_list);
 
@@ -674,6 +697,7 @@ static struct configfs_attribute *comm_attrs[] = {
 	[COMM_ATTR_LOCAL] = &comm_attr_local,
 	[COMM_ATTR_ADDR] = &comm_attr_addr,
 	[COMM_ATTR_ADDR_LIST] = &comm_attr_addr_list,
+	[COMM_ATTR_MARK] = &comm_attr_mark,
 	NULL,
 };
 
@@ -833,6 +857,20 @@ int dlm_comm_seq(int nodeid, uint32_t *seq)
 	return 0;
 }
 
+int dlm_comm_mark(int nodeid, unsigned int *mark)
+{
+	struct dlm_comm *cm;
+
+	cm = get_comm(nodeid);
+	if (!cm)
+		return -ENOENT;
+
+	*mark = cm->mark;
+	put_comm(cm);
+
+	return 0;
+}
+
 int dlm_our_nodeid(void)
 {
 	return local_comm ? local_comm->nodeid : 0;

fs/dlm/config.h

@@ -46,6 +46,7 @@ void dlm_config_exit(void);
 int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
 		     int *count_out);
 int dlm_comm_seq(int nodeid, uint32_t *seq);
+int dlm_comm_mark(int nodeid, unsigned int *mark);
 int dlm_our_nodeid(void);
 int dlm_our_addr(struct sockaddr_storage *addr, int num);
 

fs/dlm/lowcomms.c

@@ -914,6 +914,7 @@ static void sctp_connect_to_sock(struct connection *con)
 	int result;
 	int addr_len;
 	struct socket *sock;
+	unsigned int mark;
 
 	if (con->nodeid == 0) {
 		log_print("attempt to connect sock 0 foiled");
@@ -944,6 +945,13 @@ static void sctp_connect_to_sock(struct connection *con)
 	if (result < 0)
 		goto socket_err;
 
+	/* set skb mark */
+	result = dlm_comm_mark(con->nodeid, &mark);
+	if (result < 0)
+		goto bind_err;
+
+	sock_set_mark(sock->sk, mark);
+
 	con->rx_action = receive_from_sock;
 	con->connect_action = sctp_connect_to_sock;
 	add_sock(sock, con);
@@ -1006,6 +1014,7 @@ static void tcp_connect_to_sock(struct connection *con)
 	struct sockaddr_storage saddr, src_addr;
 	int addr_len;
 	struct socket *sock = NULL;
+	unsigned int mark;
 	int result;
 
 	if (con->nodeid == 0) {
@@ -1027,6 +1036,13 @@ static void tcp_connect_to_sock(struct connection *con)
 	if (result < 0)
 		goto out_err;
 
+	/* set skb mark */
+	result = dlm_comm_mark(con->nodeid, &mark);
+	if (result < 0)
+		goto out_err;
+
+	sock_set_mark(sock->sk, mark);
+
 	memset(&saddr, 0, sizeof(saddr));
 	result = nodeid_to_addr(con->nodeid, &saddr, NULL, false);
 	if (result < 0) {