Commit 89ab066d authored by Karsten Graul's avatar Karsten Graul Committed by David S. Miller
Browse files

Revert "net: simplify sock_poll_wait" 



This reverts commit dd979b4d.

This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an
internal TCP socket for the initial handshake with the remote peer.
Whenever the SMC connection can not be established this TCP socket is
used as a fallback. All socket operations on the SMC socket are then
forwarded to the TCP socket. In case of poll, the file->private_data
pointer references the SMC socket because the TCP socket has no file
assigned. This causes tcp_poll to wait on the wrong socket.

Signed-off-by: default avatarKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6b7a02f7

crypto/af_alg.c

+1 −1
Original line number Diff line number Diff line
@@ -1071,7 +1071,7 @@ __poll_t af_alg_poll(struct file *file, struct socket *sock, 
	struct af_alg_ctx *ctx = ask->private;

	__poll_t mask;



	sock_poll_wait(file, wait);

	sock_poll_wait(file, sock, wait);

	mask = 0;



	if (!ctx->more || ctx->used)

include/net/sock.h

+9 −3
Original line number Diff line number Diff line
@@ -2059,14 +2059,20 @@ static inline bool skwq_has_sleeper(struct socket_wq *wq) 
/**

 * sock_poll_wait - place memory barrier behind the poll_wait call.

 * @filp:           file

 * @sock:           socket to wait on

 * @p:              poll_table

 *

 * See the comments in the wq_has_sleeper function.

 *

 * Do not derive sock from filp->private_data here. An SMC socket establishes

 * an internal TCP socket that is used in the fallback case. All socket

 * operations on the SMC socket are then forwarded to the TCP socket. In case of

 * poll, the filp->private_data pointer references the SMC socket because the

 * TCP socket has no file assigned.

 */

static inline void sock_poll_wait(struct file *filp, poll_table *p)

static inline void sock_poll_wait(struct file *filp, struct socket *sock,

				  poll_table *p)

{

	struct socket *sock = filp->private_data;



	if (!poll_does_not_wait(p)) {

		poll_wait(filp, &sock->wq->wait, p);

		/* We need to be sure we are in sync with the

net/atm/common.c

+1 −1
Original line number Diff line number Diff line
@@ -653,7 +653,7 @@ __poll_t vcc_poll(struct file *file, struct socket *sock, poll_table *wait) 
	struct atm_vcc *vcc;

	__poll_t mask;



	sock_poll_wait(file, wait);

	sock_poll_wait(file, sock, wait);

	mask = 0;



	vcc = ATM_SD(sock);

net/caif/caif_socket.c

+1 −1
Original line number Diff line number Diff line
@@ -941,7 +941,7 @@ static __poll_t caif_poll(struct file *file, 
	__poll_t mask;

	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);



	sock_poll_wait(file, wait);

	sock_poll_wait(file, sock, wait);

	mask = 0;



	/* exceptional events? */

net/core/datagram.c

+1 −1
Original line number Diff line number Diff line
@@ -837,7 +837,7 @@ __poll_t datagram_poll(struct file *file, struct socket *sock, 
	struct sock *sk = sock->sk;

	__poll_t mask;



	sock_poll_wait(file, wait);

	sock_poll_wait(file, sock, wait);

	mask = 0;



	/* exceptional events? */

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