#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
-#include <linux/smp_lock.h>
#include <linux/notifier.h>
#include <linux/security.h>
#include <linux/jhash.h>
#include <linux/types.h>
#include <linux/audit.h>
#include <linux/selinux.h>
+#include <linux/mutex.h>
#include <net/sock.h>
#include <net/scm.h>
unsigned long state;
wait_queue_head_t wait;
struct netlink_callback *cb;
- spinlock_t cb_lock;
+ struct mutex *cb_mutex;
+ struct mutex cb_def_mutex;
void (*data_ready)(struct sock *sk, int bytes);
struct module *module;
};
unsigned long *listeners;
unsigned int nl_nonroot;
unsigned int groups;
+ struct mutex *cb_mutex;
struct module *module;
int registered;
};
static int netlink_dump(struct sock *sk);
static void netlink_destroy_callback(struct netlink_callback *cb);
+static void netlink_queue_skip(struct nlmsghdr *nlh, struct sk_buff *skb);
static DEFINE_RWLOCK(nl_table_lock);
static atomic_t nl_table_users = ATOMIC_INIT(0);
static void netlink_sock_destruct(struct sock *sk)
{
+ struct netlink_sock *nlk = nlk_sk(sk);
+
+ if (nlk->cb) {
+ if (nlk->cb->done)
+ nlk->cb->done(nlk->cb);
+ netlink_destroy_callback(nlk->cb);
+ }
+
skb_queue_purge(&sk->sk_receive_queue);
if (!sock_flag(sk, SOCK_DEAD)) {
}
BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
- BUG_TRAP(!nlk_sk(sk)->cb);
BUG_TRAP(!nlk_sk(sk)->groups);
}
.obj_size = sizeof(struct netlink_sock),
};
-static int __netlink_create(struct socket *sock, int protocol)
+static int __netlink_create(struct socket *sock, struct mutex *cb_mutex,
+ int protocol)
{
struct sock *sk;
struct netlink_sock *nlk;
sock_init_data(sock, sk);
nlk = nlk_sk(sk);
- spin_lock_init(&nlk->cb_lock);
+ if (cb_mutex)
+ nlk->cb_mutex = cb_mutex;
+ else {
+ nlk->cb_mutex = &nlk->cb_def_mutex;
+ mutex_init(nlk->cb_mutex);
+ }
init_waitqueue_head(&nlk->wait);
sk->sk_destruct = netlink_sock_destruct;
static int netlink_create(struct socket *sock, int protocol)
{
struct module *module = NULL;
+ struct mutex *cb_mutex;
struct netlink_sock *nlk;
- unsigned int groups;
int err = 0;
sock->state = SS_UNCONNECTED;
if (nl_table[protocol].registered &&
try_module_get(nl_table[protocol].module))
module = nl_table[protocol].module;
- groups = nl_table[protocol].groups;
+ cb_mutex = nl_table[protocol].cb_mutex;
netlink_unlock_table();
- if ((err = __netlink_create(sock, protocol)) < 0)
+ if ((err = __netlink_create(sock, cb_mutex, protocol)) < 0)
goto out_module;
nlk = nlk_sk(sock->sk);
return 0;
netlink_remove(sk);
+ sock_orphan(sk);
nlk = nlk_sk(sk);
- spin_lock(&nlk->cb_lock);
- if (nlk->cb) {
- if (nlk->cb->done)
- nlk->cb->done(nlk->cb);
- netlink_destroy_callback(nlk->cb);
- nlk->cb = NULL;
- }
- spin_unlock(&nlk->cb_lock);
-
- /* OK. Socket is unlinked, and, therefore,
- no new packets will arrive */
+ /*
+ * OK. Socket is unlinked, any packets that arrive now
+ * will be purged.
+ */
- sock_orphan(sk);
sock->sk = NULL;
wake_up_interruptible_all(&nlk->wait);
copied = len;
}
- skb->h.raw = skb->data;
+ skb_reset_transport_header(skb);
err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
if (msg->msg_name) {
siocb->scm = &scm;
}
siocb->scm->creds = *NETLINK_CREDS(skb);
+ if (flags & MSG_TRUNC)
+ copied = skb->len;
skb_free_datagram(sk, skb);
if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2)
netlink_dump(sk);
scm_recv(sock, msg, siocb->scm, flags);
-
out:
netlink_rcv_wake(sk);
return err ? : copied;
struct sock *
netlink_kernel_create(int unit, unsigned int groups,
void (*input)(struct sock *sk, int len),
- struct module *module)
+ struct mutex *cb_mutex, struct module *module)
{
struct socket *sock;
struct sock *sk;
if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
return NULL;
- if (__netlink_create(sock, unit) < 0)
+ if (__netlink_create(sock, cb_mutex, unit) < 0)
goto out_sock_release;
if (groups < 32)
netlink_table_grab();
nl_table[unit].groups = groups;
nl_table[unit].listeners = listeners;
+ nl_table[unit].cb_mutex = cb_mutex;
nl_table[unit].module = module;
nl_table[unit].registered = 1;
netlink_table_ungrab();
if (!skb)
goto errout;
- spin_lock(&nlk->cb_lock);
+ mutex_lock(nlk->cb_mutex);
cb = nlk->cb;
if (cb == NULL) {
len = cb->dump(skb, cb);
if (len > 0) {
- spin_unlock(&nlk->cb_lock);
+ mutex_unlock(nlk->cb_mutex);
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, len);
return 0;
if (cb->done)
cb->done(cb);
nlk->cb = NULL;
- spin_unlock(&nlk->cb_lock);
+ mutex_unlock(nlk->cb_mutex);
netlink_destroy_callback(cb);
return 0;
errout_skb:
- spin_unlock(&nlk->cb_lock);
+ mutex_unlock(nlk->cb_mutex);
kfree_skb(skb);
errout:
return err;
}
nlk = nlk_sk(sk);
/* A dump is in progress... */
- spin_lock(&nlk->cb_lock);
+ mutex_lock(nlk->cb_mutex);
if (nlk->cb) {
- spin_unlock(&nlk->cb_lock);
+ mutex_unlock(nlk->cb_mutex);
netlink_destroy_callback(cb);
sock_put(sk);
return -EBUSY;
}
nlk->cb = cb;
- spin_unlock(&nlk->cb_lock);
+ mutex_unlock(nlk->cb_mutex);
netlink_dump(sk);
sock_put(sk);
- return 0;
+
+ /* We successfully started a dump, by returning -EINTR we
+ * signal the queue mangement to interrupt processing of
+ * any netlink messages so userspace gets a chance to read
+ * the results. */
+ return -EINTR;
}
void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
}
static int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
- struct nlmsghdr *, int *))
+ struct nlmsghdr *))
{
struct nlmsghdr *nlh;
int err;
while (skb->len >= nlmsg_total_size(0)) {
- nlh = (struct nlmsghdr *) skb->data;
+ nlh = nlmsg_hdr(skb);
+ err = 0;
if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len)
return 0;
- if (cb(skb, nlh, &err) < 0) {
- /* Not an error, but we have to interrupt processing
- * here. Note: that in this case we do not pull
- * message from skb, it will be processed later.
- */
- if (err == 0)
- return -1;
+ /* Only requests are handled by the kernel */
+ if (!(nlh->nlmsg_flags & NLM_F_REQUEST))
+ goto skip;
+
+ /* Skip control messages */
+ if (nlh->nlmsg_type < NLMSG_MIN_TYPE)
+ goto skip;
+
+ err = cb(skb, nlh);
+ if (err == -EINTR) {
+ /* Not an error, but we interrupt processing */
+ netlink_queue_skip(nlh, skb);
+ return err;
+ }
+skip:
+ if (nlh->nlmsg_flags & NLM_F_ACK || err)
netlink_ack(skb, nlh, err);
- } else if (nlh->nlmsg_flags & NLM_F_ACK)
- netlink_ack(skb, nlh, 0);
netlink_queue_skip(nlh, skb);
}
*
* qlen must be initialized to 0 before the initial entry, afterwards
* the function may be called repeatedly until qlen reaches 0.
+ *
+ * The callback function may return -EINTR to signal that processing
+ * of netlink messages shall be interrupted. In this case the message
+ * currently being processed will NOT be requeued onto the receive
+ * queue.
*/
void netlink_run_queue(struct sock *sk, unsigned int *qlen,
- int (*cb)(struct sk_buff *, struct nlmsghdr *, int *))
+ int (*cb)(struct sk_buff *, struct nlmsghdr *))
{
struct sk_buff *skb;
* Pulls the given netlink message off the socket buffer so the next
* call to netlink_queue_run() will not reconsider the message.
*/
-void netlink_queue_skip(struct nlmsghdr *nlh, struct sk_buff *skb)
+static void netlink_queue_skip(struct nlmsghdr *nlh, struct sk_buff *skb)
{
int msglen = NLMSG_ALIGN(nlh->nlmsg_len);
EXPORT_SYMBOL(netlink_ack);
EXPORT_SYMBOL(netlink_run_queue);
-EXPORT_SYMBOL(netlink_queue_skip);
EXPORT_SYMBOL(netlink_broadcast);
EXPORT_SYMBOL(netlink_dump_start);
EXPORT_SYMBOL(netlink_kernel_create);
EXPORT_SYMBOL(netlink_register_notifier);
-EXPORT_SYMBOL(netlink_set_err);
EXPORT_SYMBOL(netlink_set_nonroot);
EXPORT_SYMBOL(netlink_unicast);
EXPORT_SYMBOL(netlink_unregister_notifier);
projects / powerpc.git / blobdiff