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-rw-r--r--include/linux/net.h7
-rw-r--r--include/net/sock.h23
-rw-r--r--net/core/stream.c2
-rw-r--r--net/sctp/socket.c24
-rw-r--r--net/socket.c21
5 files changed, 44 insertions, 33 deletions
diff --git a/include/linux/net.h b/include/linux/net.h
index f514e4dd5521..0b4ac7da583a 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -34,6 +34,10 @@ struct inode;
struct file;
struct net;
+/* Historically, SOCKWQ_ASYNC_NOSPACE & SOCKWQ_ASYNC_WAITDATA were located
+ * in sock->flags, but moved into sk->sk_wq->flags to be RCU protected.
+ * Eventually all flags will be in sk->sk_wq_flags.
+ */
#define SOCKWQ_ASYNC_NOSPACE 0
#define SOCKWQ_ASYNC_WAITDATA 1
#define SOCK_NOSPACE 2
@@ -89,6 +93,7 @@ struct socket_wq {
/* Note: wait MUST be first field of socket_wq */
wait_queue_head_t wait;
struct fasync_struct *fasync_list;
+ unsigned long flags; /* %SOCKWQ_ASYNC_NOSPACE, etc */
struct rcu_head rcu;
} ____cacheline_aligned_in_smp;
@@ -202,7 +207,7 @@ enum {
SOCK_WAKE_URG,
};
-int sock_wake_async(struct socket *sk, int how, int band);
+int sock_wake_async(struct socket_wq *sk_wq, int how, int band);
int sock_register(const struct net_proto_family *fam);
void sock_unregister(int family);
int __sock_create(struct net *net, int family, int type, int proto,
diff --git a/include/net/sock.h b/include/net/sock.h
index c155d09d8af4..0434138c5f95 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -384,8 +384,10 @@ struct sock {
int sk_rcvbuf;
struct sk_filter __rcu *sk_filter;
- struct socket_wq __rcu *sk_wq;
-
+ union {
+ struct socket_wq __rcu *sk_wq;
+ struct socket_wq *sk_wq_raw;
+ };
#ifdef CONFIG_XFRM
struct xfrm_policy *sk_policy[2];
#endif
@@ -2005,20 +2007,27 @@ static inline unsigned long sock_wspace(struct sock *sk)
return amt;
}
+/* Note:
+ * We use sk->sk_wq_raw, from contexts knowing this
+ * pointer is not NULL and cannot disappear/change.
+ */
static inline void sk_set_bit(int nr, struct sock *sk)
{
- set_bit(nr, &sk->sk_socket->flags);
+ set_bit(nr, &sk->sk_wq_raw->flags);
}
static inline void sk_clear_bit(int nr, struct sock *sk)
{
- clear_bit(nr, &sk->sk_socket->flags);
+ clear_bit(nr, &sk->sk_wq_raw->flags);
}
-static inline void sk_wake_async(struct sock *sk, int how, int band)
+static inline void sk_wake_async(const struct sock *sk, int how, int band)
{
- if (sock_flag(sk, SOCK_FASYNC))
- sock_wake_async(sk->sk_socket, how, band);
+ if (sock_flag(sk, SOCK_FASYNC)) {
+ rcu_read_lock();
+ sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
+ rcu_read_unlock();
+ }
}
/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
diff --git a/net/core/stream.c b/net/core/stream.c
index 43309428644d..b96f7a79e544 100644
--- a/net/core/stream.c
+++ b/net/core/stream.c
@@ -39,7 +39,7 @@ void sk_stream_write_space(struct sock *sk)
wake_up_interruptible_poll(&wq->wait, POLLOUT |
POLLWRNORM | POLLWRBAND);
if (wq && wq->fasync_list && !(sk->sk_shutdown & SEND_SHUTDOWN))
- sock_wake_async(sock, SOCK_WAKE_SPACE, POLL_OUT);
+ sock_wake_async(wq, SOCK_WAKE_SPACE, POLL_OUT);
rcu_read_unlock();
}
}
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 2353985d689c..5e35ef34008b 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -6801,26 +6801,30 @@ no_packet:
static void __sctp_write_space(struct sctp_association *asoc)
{
struct sock *sk = asoc->base.sk;
- struct socket *sock = sk->sk_socket;
- if ((sctp_wspace(asoc) > 0) && sock) {
- if (waitqueue_active(&asoc->wait))
- wake_up_interruptible(&asoc->wait);
+ if (sctp_wspace(asoc) <= 0)
+ return;
+
+ if (waitqueue_active(&asoc->wait))
+ wake_up_interruptible(&asoc->wait);
- if (sctp_writeable(sk)) {
- wait_queue_head_t *wq = sk_sleep(sk);
+ if (sctp_writeable(sk)) {
+ struct socket_wq *wq;
- if (wq && waitqueue_active(wq))
- wake_up_interruptible(wq);
+ rcu_read_lock();
+ wq = rcu_dereference(sk->sk_wq);
+ if (wq) {
+ if (waitqueue_active(&wq->wait))
+ wake_up_interruptible(&wq->wait);
/* Note that we try to include the Async I/O support
* here by modeling from the current TCP/UDP code.
* We have not tested with it yet.
*/
if (!(sk->sk_shutdown & SEND_SHUTDOWN))
- sock_wake_async(sock,
- SOCK_WAKE_SPACE, POLL_OUT);
+ sock_wake_async(wq, SOCK_WAKE_SPACE, POLL_OUT);
}
+ rcu_read_unlock();
}
}
diff --git a/net/socket.c b/net/socket.c
index 16be908205fc..456fadb3d819 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -1056,27 +1056,20 @@ static int sock_fasync(int fd, struct file *filp, int on)
return 0;
}
-/* This function may be called only under socket lock or callback_lock or rcu_lock */
+/* This function may be called only under rcu_lock */
-int sock_wake_async(struct socket *sock, int how, int band)
+int sock_wake_async(struct socket_wq *wq, int how, int band)
{
- struct socket_wq *wq;
-
- if (!sock)
- return -1;
- rcu_read_lock();
- wq = rcu_dereference(sock->wq);
- if (!wq || !wq->fasync_list) {
- rcu_read_unlock();
+ if (!wq || !wq->fasync_list)
return -1;
- }
+
switch (how) {
case SOCK_WAKE_WAITD:
- if (test_bit(SOCKWQ_ASYNC_WAITDATA, &sock->flags))
+ if (test_bit(SOCKWQ_ASYNC_WAITDATA, &wq->flags))
break;
goto call_kill;
case SOCK_WAKE_SPACE:
- if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &sock->flags))
+ if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags))
break;
/* fall through */
case SOCK_WAKE_IO:
@@ -1086,7 +1079,7 @@ call_kill:
case SOCK_WAKE_URG:
kill_fasync(&wq->fasync_list, SIGURG, band);
}
- rcu_read_unlock();
+
return 0;
}
EXPORT_SYMBOL(sock_wake_async);