/**
* tipc_bclink_update_link_state - update broadcast link state
*
- * tipc_net_lock and node lock set
+ * RCU and node lock set
*/
void tipc_bclink_update_link_state(struct tipc_node *n_ptr, u32 last_sent)
{
*
* Delay any upcoming NACK by this node if another node has already
* requested the first message this node is going to ask for.
- *
- * Only tipc_net_lock set.
*/
static void bclink_peek_nack(struct tipc_msg *msg)
{
/**
* tipc_bclink_rcv - receive a broadcast packet, and deliver upwards
*
- * tipc_net_lock is read_locked, no other locks set
+ * RCU is locked, no other locks set
*/
void tipc_bclink_rcv(struct sk_buff *buf)
{
if (!buf)
return NULL;
- read_lock_bh(&tipc_net_lock);
for (i = 0; media_info_array[i] != NULL; i++) {
for (j = 0; j < MAX_BEARERS; j++) {
b = rtnl_dereference(bearer_list[j]);
}
}
}
- read_unlock_bh(&tipc_net_lock);
return buf;
}
return -EINVAL;
}
- write_lock_bh(&tipc_net_lock);
-
m_ptr = tipc_media_find(b_names.media_name);
if (!m_ptr) {
pr_warn("Bearer <%s> rejected, media <%s> not registered\n",
name, b_names.media_name);
- goto exit;
+ return -EINVAL;
}
if (priority == TIPC_MEDIA_LINK_PRI)
if (!strcmp(name, b_ptr->name)) {
pr_warn("Bearer <%s> rejected, already enabled\n",
name);
- goto exit;
+ return -EINVAL;
}
if ((b_ptr->priority == priority) &&
(++with_this_prio > 2)) {
if (priority-- == 0) {
pr_warn("Bearer <%s> rejected, duplicate priority\n",
name);
- goto exit;
+ return -EINVAL;
}
pr_warn("Bearer <%s> priority adjustment required %u->%u\n",
name, priority + 1, priority);
if (bearer_id >= MAX_BEARERS) {
pr_warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
name, MAX_BEARERS);
- goto exit;
+ return -EINVAL;
}
b_ptr = kzalloc(sizeof(*b_ptr), GFP_ATOMIC);
- if (!b_ptr) {
- res = -ENOMEM;
- goto exit;
- }
+ if (!b_ptr)
+ return -ENOMEM;
+
strcpy(b_ptr->name, name);
b_ptr->media = m_ptr;
res = m_ptr->enable_media(b_ptr);
if (res) {
pr_warn("Bearer <%s> rejected, enable failure (%d)\n",
name, -res);
- goto exit;
+ return -EINVAL;
}
b_ptr->identity = bearer_id;
bearer_disable(b_ptr, false);
pr_warn("Bearer <%s> rejected, discovery object creation failed\n",
name);
- goto exit;
+ return -EINVAL;
}
rcu_assign_pointer(bearer_list[bearer_id], b_ptr);
pr_info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
name,
tipc_addr_string_fill(addr_string, disc_domain), priority);
-exit:
- write_unlock_bh(&tipc_net_lock);
return res;
}
*/
static int tipc_reset_bearer(struct tipc_bearer *b_ptr)
{
- read_lock_bh(&tipc_net_lock);
pr_info("Resetting bearer <%s>\n", b_ptr->name);
tipc_disc_delete(b_ptr->link_req);
tipc_link_reset_list(b_ptr->identity);
tipc_disc_create(b_ptr, &b_ptr->bcast_addr);
- read_unlock_bh(&tipc_net_lock);
return 0;
}
/**
* bearer_disable
*
- * Note: This routine assumes caller holds tipc_net_lock.
+ * Note: This routine assumes caller holds RTNL lock.
*/
static void bearer_disable(struct tipc_bearer *b_ptr, bool shutting_down)
{
struct tipc_bearer *b_ptr;
int res;
- write_lock_bh(&tipc_net_lock);
b_ptr = tipc_bearer_find(name);
if (b_ptr == NULL) {
pr_warn("Attempt to disable unknown bearer <%s>\n", name);
bearer_disable(b_ptr, false);
res = 0;
}
- write_unlock_bh(&tipc_net_lock);
return res;
}
struct tipc_node *n_ptr;
int res = -ELINKCONG;
- read_lock_bh(&tipc_net_lock);
n_ptr = tipc_node_find(dest);
if (n_ptr) {
tipc_node_lock(n_ptr);
} else {
kfree_skb(buf);
}
- read_unlock_bh(&tipc_net_lock);
return res;
}
if (list_empty(message_list))
return;
- read_lock_bh(&tipc_net_lock);
n_ptr = tipc_node_find(dest);
if (n_ptr) {
tipc_node_lock(n_ptr);
}
tipc_node_unlock(n_ptr);
}
- read_unlock_bh(&tipc_net_lock);
/* discard the messages if they couldn't be sent */
list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) {
if (unlikely(res < 0))
return res;
- read_lock_bh(&tipc_net_lock);
node = tipc_node_find(destaddr);
if (likely(node)) {
tipc_node_lock(node);
&sender->max_pkt);
exit:
tipc_node_unlock(node);
- read_unlock_bh(&tipc_net_lock);
return res;
}
*/
sender->max_pkt = l_ptr->max_pkt;
tipc_node_unlock(node);
- read_unlock_bh(&tipc_net_lock);
if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
}
tipc_node_unlock(node);
}
- read_unlock_bh(&tipc_net_lock);
/* Couldn't find a link to the destination node */
kfree_skb(buf);
char addr_string[16];
u32 i;
- read_lock_bh(&tipc_net_lock);
n_ptr = tipc_node_find((u32)addr);
- if (!n_ptr) {
- read_unlock_bh(&tipc_net_lock);
+ if (!n_ptr)
return; /* node no longer exists */
- }
tipc_node_lock(n_ptr);
}
tipc_node_unlock(n_ptr);
- read_unlock_bh(&tipc_net_lock);
}
static void link_retransmit_failure(struct tipc_link *l_ptr,
*/
void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
{
- read_lock_bh(&tipc_net_lock);
while (head) {
struct tipc_node *n_ptr;
struct tipc_link *l_ptr;
discard:
kfree_skb(buf);
}
- read_unlock_bh(&tipc_net_lock);
}
/**
/* tipc_link_find_owner - locate owner node of link by link's name
* @name: pointer to link name string
* @bearer_id: pointer to index in 'node->links' array where the link was found.
- * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
- * this also prevents link deletion.
*
* Returns pointer to node owning the link, or 0 if no matching link is found.
*/
* @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.
+ * Caller must hold RTNL lock to ensure link/bearer/media is not deleted.
*
* Returns 0 if value updated and negative value on error.
*/
" (cannot change setting on broadcast link)");
}
- read_lock_bh(&tipc_net_lock);
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");
return tipc_cfg_reply_error_string("link not found");
return tipc_cfg_reply_none();
}
- read_lock_bh(&tipc_net_lock);
node = tipc_link_find_owner(link_name, &bearer_id);
- if (!node) {
- read_unlock_bh(&tipc_net_lock);
+ if (!node)
return tipc_cfg_reply_error_string("link not found");
- }
+
tipc_node_lock(node);
l_ptr = node->links[bearer_id];
if (!l_ptr) {
tipc_node_unlock(node);
- read_unlock_bh(&tipc_net_lock);
return tipc_cfg_reply_error_string("link not found");
}
link_reset_statistics(l_ptr);
tipc_node_unlock(node);
- read_unlock_bh(&tipc_net_lock);
return tipc_cfg_reply_none();
}
if (!strcmp(name, tipc_bclink_name))
return tipc_bclink_stats(buf, buf_size);
- read_lock_bh(&tipc_net_lock);
node = tipc_link_find_owner(name, &bearer_id);
- if (!node) {
- read_unlock_bh(&tipc_net_lock);
+ if (!node)
return 0;
- }
+
tipc_node_lock(node);
l = node->links[bearer_id];
if (!l) {
tipc_node_unlock(node);
- read_unlock_bh(&tipc_net_lock);
return 0;
}
(s->accu_queue_sz / s->queue_sz_counts) : 0);
tipc_node_unlock(node);
- read_unlock_bh(&tipc_net_lock);
return ret;
}
if (dest == tipc_own_addr)
return MAX_MSG_SIZE;
- read_lock_bh(&tipc_net_lock);
n_ptr = tipc_node_find(dest);
if (n_ptr) {
tipc_node_lock(n_ptr);
res = l_ptr->max_pkt;
tipc_node_unlock(n_ptr);
}
- read_unlock_bh(&tipc_net_lock);
return res;
}
u32 max_item_buf = 0;
/* compute maximum amount of publication data to send per message */
- read_lock_bh(&tipc_net_lock);
n_ptr = tipc_node_find(node);
if (n_ptr) {
tipc_node_lock(n_ptr);
ITEM_SIZE) * ITEM_SIZE;
tipc_node_unlock(n_ptr);
}
- read_unlock_bh(&tipc_net_lock);
if (!max_item_buf)
return;
/*
* The TIPC locking policy is designed to ensure a very fine locking
* granularity, permitting complete parallel access to individual
- * port and node/link instances. The code consists of three major
+ * port and node/link instances. The code consists of four major
* locking domains, each protected with their own disjunct set of locks.
*
- * 1: The routing hierarchy.
- * Comprises the structures 'zone', 'cluster', 'node', 'link'
- * and 'bearer'. The whole hierarchy is protected by a big
- * read/write lock, tipc_net_lock, to enssure that nothing is added
- * or removed while code is accessing any of these structures.
- * This layer must not be called from the two others while they
- * hold any of their own locks.
- * Neither must it itself do any upcalls to the other two before
- * it has released tipc_net_lock and other protective locks.
+ * 1: The bearer level.
+ * RTNL lock is used to serialize the process of configuring bearer
+ * on update side, and RCU lock is applied on read side to make
+ * bearer instance valid on both paths of message transmission and
+ * reception.
*
- * Within the tipc_net_lock domain there are two sub-domains;'node' and
- * 'bearer', where local write operations are permitted,
- * provided that those are protected by individual spin_locks
- * per instance. Code holding tipc_net_lock(read) and a node spin_lock
- * is permitted to poke around in both the node itself and its
- * subordinate links. I.e, it can update link counters and queues,
- * change link state, send protocol messages, and alter the
- * "active_links" array in the node; but it can _not_ remove a link
- * or a node from the overall structure.
- * Correspondingly, individual bearers may change status within a
- * tipc_net_lock(read), protected by an individual spin_lock ber bearer
- * instance, but it needs tipc_net_lock(write) to remove/add any bearers.
+ * 2: The node and link level.
+ * All node instances are saved into two tipc_node_list and node_htable
+ * lists. The two lists are protected by node_list_lock on write side,
+ * and they are guarded with RCU lock on read side. Especially node
+ * instance is destroyed only when TIPC module is removed, and we can
+ * confirm that there has no any user who is accessing the node at the
+ * moment. Therefore, Except for iterating the two lists within RCU
+ * protection, it's no needed to hold RCU that we access node instance
+ * in other places.
*
+ * In addition, all members in node structure including link instances
+ * are protected by node spin lock.
*
- * 2: The transport level of the protocol.
- * This consists of the structures port, (and its user level
- * representations, such as user_port and tipc_sock), reference and
- * tipc_user (port.c, reg.c, socket.c).
+ * 3: The transport level of the protocol.
+ * This consists of the structures port, (and its user level
+ * representations, such as user_port and tipc_sock), reference and
+ * tipc_user (port.c, reg.c, socket.c).
*
- * This layer has four different locks:
+ * This layer has four different locks:
* - The tipc_port spin_lock. This is protecting each port instance
* from parallel data access and removal. Since we can not place
* this lock in the port itself, it has been placed in the
* There are two such lists; 'port_list', which is used for management,
* and 'wait_list', which is used to queue ports during congestion.
*
- * 3: The name table (name_table.c, name_distr.c, subscription.c)
+ * 4: The name table (name_table.c, name_distr.c, subscription.c)
* - There is one big read/write-lock (tipc_nametbl_lock) protecting the
* overall name table structure. Nothing must be added/removed to
* this structure without holding write access to it.
* - A local spin_lock protecting the queue of subscriber events.
*/
-DEFINE_RWLOCK(tipc_net_lock);
-
static void net_route_named_msg(struct sk_buff *buf)
{
struct tipc_msg *msg = buf_msg(buf);
{
char addr_string[16];
- write_lock_bh(&tipc_net_lock);
tipc_own_addr = addr;
tipc_named_reinit();
tipc_port_reinit();
tipc_bclink_init();
- write_unlock_bh(&tipc_net_lock);
-
tipc_nametbl_publish(TIPC_CFG_SRV, tipc_own_addr, tipc_own_addr,
TIPC_ZONE_SCOPE, 0, tipc_own_addr);
+
pr_info("Started in network mode\n");
pr_info("Own node address %s, network identity %u\n",
tipc_addr_string_fill(addr_string, tipc_own_addr), tipc_net_id);
tipc_nametbl_withdraw(TIPC_CFG_SRV, tipc_own_addr, 0, tipc_own_addr);
rtnl_lock();
- write_lock_bh(&tipc_net_lock);
tipc_bearer_stop();
tipc_bclink_stop();
tipc_node_stop();
- write_unlock_bh(&tipc_net_lock);
rtnl_unlock();
pr_info("Left network mode\n");
#ifndef _TIPC_NET_H
#define _TIPC_NET_H
-extern rwlock_t tipc_net_lock;
-
void tipc_net_route_msg(struct sk_buff *buf);
void tipc_net_start(u32 addr);
{
struct tipc_node *n_ptr;
- read_lock_bh(&tipc_net_lock);
n_ptr = tipc_node_find(node_addr);
if (n_ptr) {
tipc_node_lock(n_ptr);
n_ptr->block_setup &= ~WAIT_NAMES_GONE;
tipc_node_unlock(n_ptr);
}
- read_unlock_bh(&tipc_net_lock);
}
static void node_lost_contact(struct tipc_node *n_ptr)
projects / mirror_ubuntu-jammy-kernel.git / commitdiff