]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - net/unix/af_unix.c
V4L/DVB (6015): DVB: convert struct class_device to struct device
[linux-2.6-omap-h63xx.git] / net / unix / af_unix.c
index fc12ba51c1fc8223672c744e2c3eb06239741303..a05c34260e7005a346e3a507dc97149c82d2b740 100644 (file)
 
 int sysctl_unix_max_dgram_qlen __read_mostly = 10;
 
-struct hlist_head unix_socket_table[UNIX_HASH_SIZE + 1];
-DEFINE_SPINLOCK(unix_table_lock);
+static struct hlist_head unix_socket_table[UNIX_HASH_SIZE + 1];
+static DEFINE_SPINLOCK(unix_table_lock);
 static atomic_t unix_nr_socks = ATOMIC_INIT(0);
 
 #define unix_sockets_unbound   (&unix_socket_table[UNIX_HASH_SIZE])
 
 #define UNIX_ABSTRACT(sk)      (unix_sk(sk)->addr->hash != UNIX_HASH_SIZE)
 
+static struct sock *first_unix_socket(int *i)
+{
+       for (*i = 0; *i <= UNIX_HASH_SIZE; (*i)++) {
+               if (!hlist_empty(&unix_socket_table[*i]))
+                       return __sk_head(&unix_socket_table[*i]);
+       }
+       return NULL;
+}
+
+static struct sock *next_unix_socket(int *i, struct sock *s)
+{
+       struct sock *next = sk_next(s);
+       /* More in this chain? */
+       if (next)
+               return next;
+       /* Look for next non-empty chain. */
+       for ((*i)++; *i <= UNIX_HASH_SIZE; (*i)++) {
+               if (!hlist_empty(&unix_socket_table[*i]))
+                       return __sk_head(&unix_socket_table[*i]);
+       }
+       return NULL;
+}
+
+#define forall_unix_sockets(i, s) \
+       for (s = first_unix_socket(&(i)); s; s = next_unix_socket(&(i),(s)))
+
 #ifdef CONFIG_SECURITY_NETWORK
 static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
 {
@@ -174,11 +200,11 @@ static struct sock *unix_peer_get(struct sock *s)
 {
        struct sock *peer;
 
-       unix_state_rlock(s);
+       unix_state_lock(s);
        peer = unix_peer(s);
        if (peer)
                sock_hold(peer);
-       unix_state_runlock(s);
+       unix_state_unlock(s);
        return peer;
 }
 
@@ -369,7 +395,7 @@ static int unix_release_sock (struct sock *sk, int embrion)
        unix_remove_socket(sk);
 
        /* Clear state */
-       unix_state_wlock(sk);
+       unix_state_lock(sk);
        sock_orphan(sk);
        sk->sk_shutdown = SHUTDOWN_MASK;
        dentry       = u->dentry;
@@ -378,7 +404,7 @@ static int unix_release_sock (struct sock *sk, int embrion)
        u->mnt       = NULL;
        state = sk->sk_state;
        sk->sk_state = TCP_CLOSE;
-       unix_state_wunlock(sk);
+       unix_state_unlock(sk);
 
        wake_up_interruptible_all(&u->peer_wait);
 
@@ -386,12 +412,12 @@ static int unix_release_sock (struct sock *sk, int embrion)
 
        if (skpair!=NULL) {
                if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) {
-                       unix_state_wlock(skpair);
+                       unix_state_lock(skpair);
                        /* No more writes */
                        skpair->sk_shutdown = SHUTDOWN_MASK;
                        if (!skb_queue_empty(&sk->sk_receive_queue) || embrion)
                                skpair->sk_err = ECONNRESET;
-                       unix_state_wunlock(skpair);
+                       unix_state_unlock(skpair);
                        skpair->sk_state_change(skpair);
                        read_lock(&skpair->sk_callback_lock);
                        sk_wake_async(skpair,1,POLL_HUP);
@@ -448,7 +474,7 @@ static int unix_listen(struct socket *sock, int backlog)
        err = -EINVAL;
        if (!u->addr)
                goto out;                       /* No listens on an unbound socket */
-       unix_state_wlock(sk);
+       unix_state_lock(sk);
        if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN)
                goto out_unlock;
        if (backlog > sk->sk_max_ack_backlog)
@@ -462,7 +488,7 @@ static int unix_listen(struct socket *sock, int backlog)
        err = 0;
 
 out_unlock:
-       unix_state_wunlock(sk);
+       unix_state_unlock(sk);
 out:
        return err;
 }
@@ -592,7 +618,8 @@ static struct sock * unix_create1(struct socket *sock)
        u->dentry = NULL;
        u->mnt    = NULL;
        spin_lock_init(&u->lock);
-       atomic_set(&u->inflight, sock ? 0 : -1);
+       atomic_set(&u->inflight, 0);
+       INIT_LIST_HEAD(&u->link);
        mutex_init(&u->readlock); /* single task reading lock */
        init_waitqueue_head(&u->peer_wait);
        unix_insert_socket(unix_sockets_unbound, sk);
@@ -858,6 +885,31 @@ out_mknod_parent:
        goto out_up;
 }
 
+static void unix_state_double_lock(struct sock *sk1, struct sock *sk2)
+{
+       if (unlikely(sk1 == sk2) || !sk2) {
+               unix_state_lock(sk1);
+               return;
+       }
+       if (sk1 < sk2) {
+               unix_state_lock(sk1);
+               unix_state_lock_nested(sk2);
+       } else {
+               unix_state_lock(sk2);
+               unix_state_lock_nested(sk1);
+       }
+}
+
+static void unix_state_double_unlock(struct sock *sk1, struct sock *sk2)
+{
+       if (unlikely(sk1 == sk2) || !sk2) {
+               unix_state_unlock(sk1);
+               return;
+       }
+       unix_state_unlock(sk1);
+       unix_state_unlock(sk2);
+}
+
 static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
                              int alen, int flags)
 {
@@ -877,11 +929,19 @@ static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
                    !unix_sk(sk)->addr && (err = unix_autobind(sock)) != 0)
                        goto out;
 
+restart:
                other=unix_find_other(sunaddr, alen, sock->type, hash, &err);
                if (!other)
                        goto out;
 
-               unix_state_wlock(sk);
+               unix_state_double_lock(sk, other);
+
+               /* Apparently VFS overslept socket death. Retry. */
+               if (sock_flag(other, SOCK_DEAD)) {
+                       unix_state_double_unlock(sk, other);
+                       sock_put(other);
+                       goto restart;
+               }
 
                err = -EPERM;
                if (!unix_may_send(sk, other))
@@ -896,7 +956,7 @@ static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
                 *      1003.1g breaking connected state with AF_UNSPEC
                 */
                other = NULL;
-               unix_state_wlock(sk);
+               unix_state_double_lock(sk, other);
        }
 
        /*
@@ -905,19 +965,19 @@ static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
        if (unix_peer(sk)) {
                struct sock *old_peer = unix_peer(sk);
                unix_peer(sk)=other;
-               unix_state_wunlock(sk);
+               unix_state_double_unlock(sk, other);
 
                if (other != old_peer)
                        unix_dgram_disconnected(sk, old_peer);
                sock_put(old_peer);
        } else {
                unix_peer(sk)=other;
-               unix_state_wunlock(sk);
+               unix_state_double_unlock(sk, other);
        }
        return 0;
 
 out_unlock:
-       unix_state_wunlock(sk);
+       unix_state_double_unlock(sk, other);
        sock_put(other);
 out:
        return err;
@@ -936,7 +996,7 @@ static long unix_wait_for_peer(struct sock *other, long timeo)
                (skb_queue_len(&other->sk_receive_queue) >
                 other->sk_max_ack_backlog);
 
-       unix_state_runlock(other);
+       unix_state_unlock(other);
 
        if (sched)
                timeo = schedule_timeout(timeo);
@@ -994,11 +1054,11 @@ restart:
                goto out;
 
        /* Latch state of peer */
-       unix_state_rlock(other);
+       unix_state_lock(other);
 
        /* Apparently VFS overslept socket death. Retry. */
        if (sock_flag(other, SOCK_DEAD)) {
-               unix_state_runlock(other);
+               unix_state_unlock(other);
                sock_put(other);
                goto restart;
        }
@@ -1048,18 +1108,18 @@ restart:
                goto out_unlock;
        }
 
-       unix_state_wlock_nested(sk);
+       unix_state_lock_nested(sk);
 
        if (sk->sk_state != st) {
-               unix_state_wunlock(sk);
-               unix_state_runlock(other);
+               unix_state_unlock(sk);
+               unix_state_unlock(other);
                sock_put(other);
                goto restart;
        }
 
        err = security_unix_stream_connect(sock, other->sk_socket, newsk);
        if (err) {
-               unix_state_wunlock(sk);
+               unix_state_unlock(sk);
                goto out_unlock;
        }
 
@@ -1096,23 +1156,20 @@ restart:
        smp_mb__after_atomic_inc();     /* sock_hold() does an atomic_inc() */
        unix_peer(sk)   = newsk;
 
-       unix_state_wunlock(sk);
+       unix_state_unlock(sk);
 
        /* take ten and and send info to listening sock */
        spin_lock(&other->sk_receive_queue.lock);
        __skb_queue_tail(&other->sk_receive_queue, skb);
-       /* Undo artificially decreased inflight after embrion
-        * is installed to listening socket. */
-       atomic_inc(&newu->inflight);
        spin_unlock(&other->sk_receive_queue.lock);
-       unix_state_runlock(other);
+       unix_state_unlock(other);
        other->sk_data_ready(other, 0);
        sock_put(other);
        return 0;
 
 out_unlock:
        if (other)
-               unix_state_runlock(other);
+               unix_state_unlock(other);
 
 out:
        if (skb)
@@ -1178,10 +1235,10 @@ static int unix_accept(struct socket *sock, struct socket *newsock, int flags)
        wake_up_interruptible(&unix_sk(sk)->peer_wait);
 
        /* attach accepted sock to socket */
-       unix_state_wlock(tsk);
+       unix_state_lock(tsk);
        newsock->state = SS_CONNECTED;
        sock_graft(tsk, newsock);
-       unix_state_wunlock(tsk);
+       unix_state_unlock(tsk);
        return 0;
 
 out:
@@ -1208,7 +1265,7 @@ static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_
        }
 
        u = unix_sk(sk);
-       unix_state_rlock(sk);
+       unix_state_lock(sk);
        if (!u->addr) {
                sunaddr->sun_family = AF_UNIX;
                sunaddr->sun_path[0] = 0;
@@ -1219,7 +1276,7 @@ static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_
                *uaddr_len = addr->len;
                memcpy(sunaddr, addr->name, *uaddr_len);
        }
-       unix_state_runlock(sk);
+       unix_state_unlock(sk);
        sock_put(sk);
 out:
        return err;
@@ -1337,7 +1394,7 @@ restart:
                        goto out_free;
        }
 
-       unix_state_rlock(other);
+       unix_state_lock(other);
        err = -EPERM;
        if (!unix_may_send(sk, other))
                goto out_unlock;
@@ -1347,20 +1404,20 @@ restart:
                 *      Check with 1003.1g - what should
                 *      datagram error
                 */
-               unix_state_runlock(other);
+               unix_state_unlock(other);
                sock_put(other);
 
                err = 0;
-               unix_state_wlock(sk);
+               unix_state_lock(sk);
                if (unix_peer(sk) == other) {
                        unix_peer(sk)=NULL;
-                       unix_state_wunlock(sk);
+                       unix_state_unlock(sk);
 
                        unix_dgram_disconnected(sk, other);
                        sock_put(other);
                        err = -ECONNREFUSED;
                } else {
-                       unix_state_wunlock(sk);
+                       unix_state_unlock(sk);
                }
 
                other = NULL;
@@ -1397,14 +1454,14 @@ restart:
        }
 
        skb_queue_tail(&other->sk_receive_queue, skb);
-       unix_state_runlock(other);
+       unix_state_unlock(other);
        other->sk_data_ready(other, len);
        sock_put(other);
        scm_destroy(siocb->scm);
        return len;
 
 out_unlock:
-       unix_state_runlock(other);
+       unix_state_unlock(other);
 out_free:
        kfree_skb(skb);
 out:
@@ -1494,14 +1551,14 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
                        goto out_err;
                }
 
-               unix_state_rlock(other);
+               unix_state_lock(other);
 
                if (sock_flag(other, SOCK_DEAD) ||
                    (other->sk_shutdown & RCV_SHUTDOWN))
                        goto pipe_err_free;
 
                skb_queue_tail(&other->sk_receive_queue, skb);
-               unix_state_runlock(other);
+               unix_state_unlock(other);
                other->sk_data_ready(other, size);
                sent+=size;
        }
@@ -1512,7 +1569,7 @@ static int unix_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
        return sent;
 
 pipe_err_free:
-       unix_state_runlock(other);
+       unix_state_unlock(other);
        kfree_skb(skb);
 pipe_err:
        if (sent==0 && !(msg->msg_flags&MSG_NOSIGNAL))
@@ -1641,7 +1698,7 @@ static long unix_stream_data_wait(struct sock * sk, long timeo)
 {
        DEFINE_WAIT(wait);
 
-       unix_state_rlock(sk);
+       unix_state_lock(sk);
 
        for (;;) {
                prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
@@ -1654,14 +1711,14 @@ static long unix_stream_data_wait(struct sock * sk, long timeo)
                        break;
 
                set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
-               unix_state_runlock(sk);
+               unix_state_unlock(sk);
                timeo = schedule_timeout(timeo);
-               unix_state_rlock(sk);
+               unix_state_lock(sk);
                clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
        }
 
        finish_wait(sk->sk_sleep, &wait);
-       unix_state_runlock(sk);
+       unix_state_unlock(sk);
        return timeo;
 }
 
@@ -1711,20 +1768,23 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
                int chunk;
                struct sk_buff *skb;
 
+               unix_state_lock(sk);
                skb = skb_dequeue(&sk->sk_receive_queue);
                if (skb==NULL)
                {
                        if (copied >= target)
-                               break;
+                               goto unlock;
 
                        /*
                         *      POSIX 1003.1g mandates this order.
                         */
 
                        if ((err = sock_error(sk)) != 0)
-                               break;
+                               goto unlock;
                        if (sk->sk_shutdown & RCV_SHUTDOWN)
-                               break;
+                               goto unlock;
+
+                       unix_state_unlock(sk);
                        err = -EAGAIN;
                        if (!timeo)
                                break;
@@ -1738,7 +1798,11 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
                        }
                        mutex_lock(&u->readlock);
                        continue;
+ unlock:
+                       unix_state_unlock(sk);
+                       break;
                }
+               unix_state_unlock(sk);
 
                if (check_creds) {
                        /* Never glue messages from different writers */
@@ -1816,12 +1880,12 @@ static int unix_shutdown(struct socket *sock, int mode)
        mode = (mode+1)&(RCV_SHUTDOWN|SEND_SHUTDOWN);
 
        if (mode) {
-               unix_state_wlock(sk);
+               unix_state_lock(sk);
                sk->sk_shutdown |= mode;
                other=unix_peer(sk);
                if (other)
                        sock_hold(other);
-               unix_state_wunlock(sk);
+               unix_state_unlock(sk);
                sk->sk_state_change(sk);
 
                if (other &&
@@ -1833,9 +1897,9 @@ static int unix_shutdown(struct socket *sock, int mode)
                                peer_mode |= SEND_SHUTDOWN;
                        if (mode&SEND_SHUTDOWN)
                                peer_mode |= RCV_SHUTDOWN;
-                       unix_state_wlock(other);
+                       unix_state_lock(other);
                        other->sk_shutdown |= peer_mode;
-                       unix_state_wunlock(other);
+                       unix_state_unlock(other);
                        other->sk_state_change(other);
                        read_lock(&other->sk_callback_lock);
                        if (peer_mode == SHUTDOWN_MASK)
@@ -1973,7 +2037,7 @@ static int unix_seq_show(struct seq_file *seq, void *v)
        else {
                struct sock *s = v;
                struct unix_sock *u = unix_sk(s);
-               unix_state_rlock(s);
+               unix_state_lock(s);
 
                seq_printf(seq, "%p: %08X %08X %08X %04X %02X %5lu",
                        s,
@@ -2001,14 +2065,14 @@ static int unix_seq_show(struct seq_file *seq, void *v)
                        for ( ; i < len; i++)
                                seq_putc(seq, u->addr->name->sun_path[i]);
                }
-               unix_state_runlock(s);
+               unix_state_unlock(s);
                seq_putc(seq, '\n');
        }
 
        return 0;
 }
 
-static struct seq_operations unix_seq_ops = {
+static const struct seq_operations unix_seq_ops = {
        .start  = unix_seq_start,
        .next   = unix_seq_next,
        .stop   = unix_seq_stop,