/*
- * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include "netlink.h"
#include "netlink-protocol.h"
#include "ofpbuf.h"
+#include "ovs-thread.h"
#include "poll-loop.h"
#include "socket-util.h"
#include "util.h"
uint32_t next_seq;
uint32_t pid;
int protocol;
- struct nl_dump *dump;
unsigned int rcvbuf; /* Receive buffer size (SO_RCVBUF). */
};
* Initialized by nl_sock_create(). */
static int max_iovs;
-static int nl_sock_cow__(struct nl_sock *);
+static int nl_pool_alloc(int protocol, struct nl_sock **sockp);
+static void nl_pool_release(struct nl_sock *);
/* Creates a new netlink socket for the given netlink 'protocol'
* (NETLINK_ROUTE, NETLINK_GENERIC, ...). Returns 0 and sets '*sockp' to the
- * new socket if successful, otherwise returns a positive errno value. */
+ * new socket if successful, otherwise returns a positive errno value. */
int
nl_sock_create(int protocol, struct nl_sock **sockp)
{
+ static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
struct nl_sock *sock;
struct sockaddr_nl local, remote;
socklen_t local_size;
int rcvbuf;
int retval = 0;
- if (!max_iovs) {
+ if (ovsthread_once_start(&once)) {
int save_errno = errno;
errno = 0;
}
errno = save_errno;
+ ovsthread_once_done(&once);
}
*sockp = NULL;
goto error;
}
sock->protocol = protocol;
- sock->dump = NULL;
sock->next_seq = 1;
rcvbuf = 1024 * 1024;
nl_sock_destroy(struct nl_sock *sock)
{
if (sock) {
- if (sock->dump) {
- sock->dump = NULL;
- } else {
- close(sock->fd);
- free(sock);
- }
+ close(sock->fd);
+ free(sock);
}
}
int
nl_sock_join_mcgroup(struct nl_sock *sock, unsigned int multicast_group)
{
- int error = nl_sock_cow__(sock);
- if (error) {
- return error;
- }
if (setsockopt(sock->fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP,
&multicast_group, sizeof multicast_group) < 0) {
VLOG_WARN("could not join multicast group %u (%s)",
int
nl_sock_leave_mcgroup(struct nl_sock *sock, unsigned int multicast_group)
{
- ovs_assert(!sock->dump);
if (setsockopt(sock->fd, SOL_NETLINK, NETLINK_DROP_MEMBERSHIP,
&multicast_group, sizeof multicast_group) < 0) {
VLOG_WARN("could not leave multicast group %u (%s)",
nl_sock_send_seq(struct nl_sock *sock, const struct ofpbuf *msg,
uint32_t nlmsg_seq, bool wait)
{
- int error = nl_sock_cow__(sock);
- if (error) {
- return error;
- }
return nl_sock_send__(sock, msg, nlmsg_seq, wait);
}
int
nl_sock_recv(struct nl_sock *sock, struct ofpbuf *buf, bool wait)
{
- int error = nl_sock_cow__(sock);
- if (error) {
- return error;
- }
return nl_sock_recv__(sock, buf, wait);
}
return;
}
- error = nl_sock_cow__(sock);
- if (error) {
- nl_sock_record_errors__(transactions, n, error);
- return;
- }
-
/* In theory, every request could have a 64 kB reply. But the default and
* maximum socket rcvbuf size with typical Dom0 memory sizes both tend to
* be a bit below 128 kB, so that would only allow a single message in a
int
nl_sock_drain(struct nl_sock *sock)
{
- int error = nl_sock_cow__(sock);
- if (error) {
- return error;
- }
return drain_rcvbuf(sock->fd);
}
-/* The client is attempting some operation on 'sock'. If 'sock' has an ongoing
- * dump operation, then replace 'sock''s fd with a new socket and hand 'sock''s
- * old fd over to the dump. */
-static int
-nl_sock_cow__(struct nl_sock *sock)
-{
- struct nl_sock *copy;
- uint32_t tmp_pid;
- int tmp_fd;
- int error;
-
- if (!sock->dump) {
- return 0;
- }
-
- error = nl_sock_clone(sock, ©);
- if (error) {
- return error;
- }
-
- tmp_fd = sock->fd;
- sock->fd = copy->fd;
- copy->fd = tmp_fd;
-
- tmp_pid = sock->pid;
- sock->pid = copy->pid;
- copy->pid = tmp_pid;
-
- sock->dump->sock = copy;
- sock->dump = NULL;
-
- return 0;
-}
-
-/* Starts a Netlink "dump" operation, by sending 'request' to the kernel via
- * 'sock', and initializes 'dump' to reflect the state of the operation.
+/* Starts a Netlink "dump" operation, by sending 'request' to the kernel on a
+ * Netlink socket created with the given 'protocol', and initializes 'dump' to
+ * reflect the state of the operation.
*
* nlmsg_len in 'msg' will be finalized to match msg->size, and nlmsg_pid will
- * be set to 'sock''s pid, before the message is sent. NLM_F_DUMP and
- * NLM_F_ACK will be set in nlmsg_flags.
- *
- * This Netlink socket library is designed to ensure that the dump is reliable
- * and that it will not interfere with other operations on 'sock', including
- * destroying or sending and receiving messages on 'sock'. One corner case is
- * not handled:
+ * be set to the Netlink socket's pid, before the message is sent. NLM_F_DUMP
+ * and NLM_F_ACK will be set in nlmsg_flags.
*
- * - If 'sock' has been used to send a request (e.g. with nl_sock_send())
- * whose response has not yet been received (e.g. with nl_sock_recv()).
- * This is unusual: usually nl_sock_transact() is used to send a message
- * and receive its reply all in one go.
+ * The design of this Netlink socket library ensures that the dump is reliable.
*
* This function provides no status indication. An error status for the entire
* dump operation is provided when it is completed by calling nl_dump_done().
*
* The caller is responsible for destroying 'request'.
- *
- * The new 'dump' is independent of 'sock'. 'sock' and 'dump' may be destroyed
- * in either order.
*/
void
-nl_dump_start(struct nl_dump *dump,
- struct nl_sock *sock, const struct ofpbuf *request)
+nl_dump_start(struct nl_dump *dump, int protocol, const struct ofpbuf *request)
{
ofpbuf_init(&dump->buffer, 4096);
- if (sock->dump) {
- /* 'sock' already has an ongoing dump. Clone the socket because
- * Netlink only allows one dump at a time. */
- dump->status = nl_sock_clone(sock, &dump->sock);
- if (dump->status) {
- return;
- }
- } else {
- sock->dump = dump;
- dump->sock = sock;
- dump->status = 0;
+ dump->status = nl_pool_alloc(protocol, &dump->sock);
+ if (dump->status) {
+ return;
}
nl_msg_nlmsghdr(request)->nlmsg_flags |= NLM_F_DUMP | NLM_F_ACK;
- dump->status = nl_sock_send__(sock, request, nl_sock_allocate_seq(sock, 1),
- true);
+ dump->status = nl_sock_send__(dump->sock, request,
+ nl_sock_allocate_seq(dump->sock, 1), true);
dump->seq = nl_msg_nlmsghdr(request)->nlmsg_seq;
}
nl_dump_done(struct nl_dump *dump)
{
/* Drain any remaining messages that the client didn't read. Otherwise the
- * kernel will continue to queue them up and waste buffer space. */
+ * kernel will continue to queue them up and waste buffer space.
+ *
+ * XXX We could just destroy and discard the socket in this case. */
while (!dump->status) {
struct ofpbuf reply;
if (!nl_dump_next(dump, &reply)) {
ovs_assert(dump->status);
}
}
-
- if (dump->sock) {
- if (dump->sock->dump) {
- dump->sock->dump = NULL;
- } else {
- nl_sock_destroy(dump->sock);
- }
- }
+ nl_pool_release(dump->sock);
ofpbuf_uninit(&dump->buffer);
return dump->status == EOF ? 0 : dump->status;
}
/* Finds the multicast group called 'group_name' in genl family 'family_name'.
* When successful, writes its result to 'multicast_group' and returns 0.
* Otherwise, clears 'multicast_group' and returns a positive error code.
- *
- * Some kernels do not support looking up a multicast group with this function.
- * In this case, 'multicast_group' will be populated with 'fallback'. */
+ */
int
nl_lookup_genl_mcgroup(const char *family_name, const char *group_name,
- unsigned int *multicast_group, unsigned int fallback)
+ unsigned int *multicast_group)
{
struct nlattr *family_attrs[ARRAY_SIZE(family_policy)];
const struct nlattr *mc;
}
if (!family_attrs[CTRL_ATTR_MCAST_GROUPS]) {
- *multicast_group = fallback;
- VLOG_WARN("%s-%s: has no multicast group, using fallback %d",
- family_name, group_name, *multicast_group);
- error = 0;
+ error = EPROTO;
goto exit;
}
}
return *number > 0 ? 0 : -*number;
}
+\f
+struct nl_pool {
+ struct nl_sock *socks[16];
+ int n;
+};
+
+static struct ovs_mutex pool_mutex = OVS_MUTEX_INITIALIZER;
+static struct nl_pool pools[MAX_LINKS] OVS_GUARDED_BY(pool_mutex);
+
+static int
+nl_pool_alloc(int protocol, struct nl_sock **sockp)
+{
+ struct nl_sock *sock = NULL;
+ struct nl_pool *pool;
+
+ ovs_assert(protocol >= 0 && protocol < ARRAY_SIZE(pools));
+
+ ovs_mutex_lock(&pool_mutex);
+ pool = &pools[protocol];
+ if (pool->n > 0) {
+ sock = pool->socks[--pool->n];
+ }
+ ovs_mutex_unlock(&pool_mutex);
+
+ if (sock) {
+ *sockp = sock;
+ return 0;
+ } else {
+ return nl_sock_create(protocol, sockp);
+ }
+}
+
+static void
+nl_pool_release(struct nl_sock *sock)
+{
+ if (sock) {
+ struct nl_pool *pool = &pools[sock->protocol];
+
+ ovs_mutex_lock(&pool_mutex);
+ if (pool->n < ARRAY_SIZE(pool->socks)) {
+ pool->socks[pool->n++] = sock;
+ sock = NULL;
+ }
+ ovs_mutex_unlock(&pool_mutex);
+
+ nl_sock_destroy(sock);
+ }
+}
+
+int
+nl_transact(int protocol, const struct ofpbuf *request,
+ struct ofpbuf **replyp)
+{
+ struct nl_sock *sock;
+ int error;
+
+ error = nl_pool_alloc(protocol, &sock);
+ if (error) {
+ *replyp = NULL;
+ return error;
+ }
+
+ error = nl_sock_transact(sock, request, replyp);
+
+ nl_pool_release(sock);
+ return error;
+}
+
+void
+nl_transact_multiple(int protocol,
+ struct nl_transaction **transactions, size_t n)
+{
+ struct nl_sock *sock;
+ int error;
+
+ error = nl_pool_alloc(protocol, &sock);
+ if (!error) {
+ nl_sock_transact_multiple(sock, transactions, n);
+ nl_pool_release(sock);
+ } else {
+ nl_sock_record_errors__(transactions, n, error);
+ }
+}
+
\f
static uint32_t
nl_sock_allocate_seq(struct nl_sock *sock, unsigned int n)
git://git.onelab.eu / sliver-openvswitch.git / blobdiff