3 files changed, 127 insertions, 49 deletions

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index aa37261626d6..b40e98adfd7f 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -65,10 +65,10 @@ static int media_name_valid(const char *name)
 }
 
 /**
- * media_find - locates specified media object by name
+ * tipc_media_find - locates specified media object by name
  */
 
-static struct media *media_find(const char *name)
+struct media *tipc_media_find(const char *name)
 {
         u32 i;
 
@@ -118,7 +118,7 @@ int  tipc_register_media(struct media *m_ptr)
                 goto exit;
         if (media_count >= MAX_MEDIA)
                 goto exit;
-        if (media_find(m_ptr->name) || media_find_id(m_ptr->type_id))
+        if (tipc_media_find(m_ptr->name) || media_find_id(m_ptr->type_id))
                 goto exit;
 
         media_list[media_count] = m_ptr;
@@ -229,10 +229,10 @@ static int bearer_name_validate(const char *name,
 }
 
 /**
- * bearer_find - locates bearer object with matching bearer name
+ * tipc_bearer_find - locates bearer object with matching bearer name
  */
 
-static struct tipc_bearer *bearer_find(const char *name)
+struct tipc_bearer *tipc_bearer_find(const char *name)
 {
         struct tipc_bearer *b_ptr;
         u32 i;
@@ -463,7 +463,7 @@ int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
 
         write_lock_bh(&tipc_net_lock);
 
-        m_ptr = media_find(b_name.media_name);
+        m_ptr = tipc_media_find(b_name.media_name);
         if (!m_ptr) {
                 warn("Bearer <%s> rejected, media <%s> not registered\n", name,
                      b_name.media_name);
@@ -513,6 +513,8 @@ restart:
 
         b_ptr->identity = bearer_id;
         b_ptr->media = m_ptr;
+        b_ptr->tolerance = m_ptr->tolerance;
+        b_ptr->window = m_ptr->window;
         b_ptr->net_plane = bearer_id + 'A';
         b_ptr->active = 1;
         b_ptr->priority = priority;
@@ -546,7 +548,7 @@ int tipc_block_bearer(const char *name)
         struct link *temp_l_ptr;
 
         read_lock_bh(&tipc_net_lock);
-        b_ptr = bearer_find(name);
+        b_ptr = tipc_bearer_find(name);
         if (!b_ptr) {
                 warn("Attempt to block unknown bearer <%s>\n", name);
                 read_unlock_bh(&tipc_net_lock);
@@ -600,7 +602,7 @@ int tipc_disable_bearer(const char *name)
         int res;
 
         write_lock_bh(&tipc_net_lock);
-        b_ptr = bearer_find(name);
+        b_ptr = tipc_bearer_find(name);
         if (b_ptr == NULL) {
                 warn("Attempt to disable unknown bearer <%s>\n", name);
                 res = -EINVAL;
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 54a5a575d69a..cfe77c4b20f9 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -118,6 +118,8 @@ struct media {
  * @name: bearer name (format = media:interface)
  * @media: ptr to media structure associated with bearer
  * @priority: default link priority for bearer
+ * @window: default window size for bearer
+ * @tolerance: default link tolerance for bearer
  * @identity: array index of this bearer within TIPC bearer array
  * @link_req: ptr to (optional) structure making periodic link setup requests
  * @links: list of non-congested links associated with bearer
@@ -139,6 +141,8 @@ struct tipc_bearer {
         spinlock_t lock;
         struct media *media;
         u32 priority;
+        u32 window;
+        u32 tolerance;
         u32 identity;
         struct link_req *link_req;
         struct list_head links;
@@ -176,6 +180,8 @@ int tipc_disable_bearer(const char *name);
 int  tipc_eth_media_start(void);
 void tipc_eth_media_stop(void);
 
+int tipc_media_set_priority(const char *name, u32 new_value);
+int tipc_media_set_window(const char *name, u32 new_value);
 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a);
 struct sk_buff *tipc_media_get_names(void);
 
@@ -183,7 +189,9 @@ struct sk_buff *tipc_bearer_get_names(void);
 void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest);
 void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest);
 void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct link *l_ptr);
+struct tipc_bearer *tipc_bearer_find(const char *name);
 struct tipc_bearer *tipc_bearer_find_interface(const char *if_name);
+struct media *tipc_media_find(const char *name);
 int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr, struct link *l_ptr);
 int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct link *l_ptr);
 void tipc_bearer_stop(void);
diff --git a/net/tipc/link.c b/net/tipc/link.c
index ae98a72da11a..332915e43043 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -343,7 +343,7 @@ struct link *tipc_link_create(struct tipc_node *n_ptr,
         l_ptr->checkpoint = 1;
         l_ptr->peer_session = INVALID_SESSION;
         l_ptr->b_ptr = b_ptr;
-        link_set_supervision_props(l_ptr, b_ptr->media->tolerance);
+        link_set_supervision_props(l_ptr, b_ptr->tolerance);
         l_ptr->state = RESET_UNKNOWN;
 
         l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
@@ -355,7 +355,7 @@ struct link *tipc_link_create(struct tipc_node *n_ptr,
         strcpy((char *)msg_data(msg), if_name);
 
         l_ptr->priority = b_ptr->priority;
-        tipc_link_set_queue_limits(l_ptr, b_ptr->media->window);
+        tipc_link_set_queue_limits(l_ptr, b_ptr->window);
 
         link_init_max_pkt(l_ptr);
 
@@ -2754,13 +2754,113 @@ static struct link *link_find_link(const char *name, struct tipc_node **node)
         return l_ptr;
 }
 
+/**
+ * link_value_is_valid -- validate proposed link tolerance/priority/window
+ *
+ * @cmd - value type (TIPC_CMD_SET_LINK_*)
+ * @new_value - the new value
+ *
+ * Returns 1 if value is within range, 0 if not.
+ */
+
+static int link_value_is_valid(u16 cmd, u32 new_value)
+{
+        switch (cmd) {
+        case TIPC_CMD_SET_LINK_TOL:
+                return (new_value >= TIPC_MIN_LINK_TOL) &&
+                        (new_value <= TIPC_MAX_LINK_TOL);
+        case TIPC_CMD_SET_LINK_PRI:
+                return (new_value <= TIPC_MAX_LINK_PRI);
+        case TIPC_CMD_SET_LINK_WINDOW:
+                return (new_value >= TIPC_MIN_LINK_WIN) &&
+                        (new_value <= TIPC_MAX_LINK_WIN);
+        }
+        return 0;
+}
+
+
+/**
+ * link_cmd_set_value - change priority/tolerance/window for link/bearer/media
+ * @name - ptr to link, bearer, or media name
+ * @new_value - new value of link, bearer, or media setting
+ * @cmd - which link, bearer, or media attribute to set (TIPC_CMD_SET_LINK_*)
+ *
+ * Caller must hold 'tipc_net_lock' to ensure link/bearer/media is not deleted.
+ *
+ * Returns 0 if value updated and negative value on error.
+ */
+
+static int link_cmd_set_value(const char *name, u32 new_value, u16 cmd)
+{
+        struct tipc_node *node;
+        struct link *l_ptr;
+        struct tipc_bearer *b_ptr;
+        struct media *m_ptr;
+
+        l_ptr = link_find_link(name, &node);
+        if (l_ptr) {
+                /*
+                 * acquire node lock for tipc_link_send_proto_msg().
+                 * see "TIPC locking policy" in net.c.
+                 */
+                tipc_node_lock(node);
+                switch (cmd) {
+                case TIPC_CMD_SET_LINK_TOL:
+                        link_set_supervision_props(l_ptr, new_value);
+                        tipc_link_send_proto_msg(l_ptr,
+                                STATE_MSG, 0, 0, new_value, 0, 0);
+                        break;
+                case TIPC_CMD_SET_LINK_PRI:
+                        l_ptr->priority = new_value;
+                        tipc_link_send_proto_msg(l_ptr,
+                                STATE_MSG, 0, 0, 0, new_value, 0);
+                        break;
+                case TIPC_CMD_SET_LINK_WINDOW:
+                        tipc_link_set_queue_limits(l_ptr, new_value);
+                        break;
+                }
+                tipc_node_unlock(node);
+                return 0;
+        }
+
+        b_ptr = tipc_bearer_find(name);
+        if (b_ptr) {
+                switch (cmd) {
+                case TIPC_CMD_SET_LINK_TOL:
+                        b_ptr->tolerance = new_value;
+                        return 0;
+                case TIPC_CMD_SET_LINK_PRI:
+                        b_ptr->priority = new_value;
+                        return 0;
+                case TIPC_CMD_SET_LINK_WINDOW:
+                        b_ptr->window = new_value;
+                        return 0;
+                }
+                return -EINVAL;
+        }
+
+        m_ptr = tipc_media_find(name);
+        if (!m_ptr)
+                return -ENODEV;
+        switch (cmd) {
+        case TIPC_CMD_SET_LINK_TOL:
+                m_ptr->tolerance = new_value;
+                return 0;
+        case TIPC_CMD_SET_LINK_PRI:
+                m_ptr->priority = new_value;
+                return 0;
+        case TIPC_CMD_SET_LINK_WINDOW:
+                m_ptr->window = new_value;
+                return 0;
+        }
+        return -EINVAL;
+}
+
 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
                                      u16 cmd)
 {
         struct tipc_link_config *args;
         u32 new_value;
-        struct link *l_ptr;
-        struct tipc_node *node;
         int res;
 
         if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
@@ -2769,6 +2869,10 @@ struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space
         args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
         new_value = ntohl(args->value);
 
+        if (!link_value_is_valid(cmd, new_value))
+                return tipc_cfg_reply_error_string(
+                        "cannot change, value invalid");
+
         if (!strcmp(args->name, tipc_bclink_name)) {
                 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
                     (tipc_bclink_set_queue_limits(new_value) == 0))
@@ -2778,43 +2882,7 @@ struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space
         }
 
         read_lock_bh(&tipc_net_lock);
-        l_ptr = link_find_link(args->name, &node);
-        if (!l_ptr) {
-                read_unlock_bh(&tipc_net_lock);
-                return tipc_cfg_reply_error_string("link not found");
-        }
-
-        tipc_node_lock(node);
-        res = -EINVAL;
-        switch (cmd) {
-        case TIPC_CMD_SET_LINK_TOL:
-                if ((new_value >= TIPC_MIN_LINK_TOL) &&
-                    (new_value <= TIPC_MAX_LINK_TOL)) {
-                        link_set_supervision_props(l_ptr, new_value);
-                        tipc_link_send_proto_msg(l_ptr, STATE_MSG,
-                                                 0, 0, new_value, 0, 0);
-                        res = 0;
-                }
-                break;
-        case TIPC_CMD_SET_LINK_PRI:
-                if ((new_value >= TIPC_MIN_LINK_PRI) &&
-                    (new_value <= TIPC_MAX_LINK_PRI)) {
-                        l_ptr->priority = new_value;
-                        tipc_link_send_proto_msg(l_ptr, STATE_MSG,
-                                                 0, 0, 0, new_value, 0);
-                        res = 0;
-                }
-                break;
-        case TIPC_CMD_SET_LINK_WINDOW:
-                if ((new_value >= TIPC_MIN_LINK_WIN) &&
-                    (new_value <= TIPC_MAX_LINK_WIN)) {
-                        tipc_link_set_queue_limits(l_ptr, new_value);
-                        res = 0;
-                }
-                break;
-        }
-        tipc_node_unlock(node);
-
+        res = link_cmd_set_value(args->name, new_value, cmd);
         read_unlock_bh(&tipc_net_lock);
         if (res)
                 return tipc_cfg_reply_error_string("cannot change link setting");