From: Stefan Raspl <raspl@linux.ibm.com>
Subject: net/smc: handle sockopt TCP_DEFER_ACCEPT
Patch-mainline: v4.18-rc1
Git-commit: abb190f194d082cbb7520e692d78d3ddf050e7b1
References: FATE#325694, LTC#167874, bsc#1113480
Summary: net/smc: SMC-R MVP
Description: Add latest upstream patches to push SMC-R to the MVP level
Upstream-Description:
net/smc: handle sockopt TCP_DEFER_ACCEPT
If sockopt TCP_DEFER_ACCEPT is set, the accept is delayed till
data is available.
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
net/smc/af_smc.c | 26 +++++++++++++++++++++++++-
net/smc/smc.h | 4 ++++
net/smc/smc_rx.c | 2 +-
net/smc/smc_rx.h | 1 +
4 files changed, 31 insertions(+), 2 deletions(-)
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -1041,6 +1041,7 @@ static int smc_accept(struct socket *soc
if (lsmc->sk.sk_state != SMC_LISTEN) {
rc = -EINVAL;
+ release_sock(sk);
goto out;
}
@@ -1068,9 +1069,29 @@ static int smc_accept(struct socket *soc
if (!rc)
rc = sock_error(nsk);
+ release_sock(sk);
+ if (rc)
+ goto out;
+
+ if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) {
+ /* wait till data arrives on the socket */
+ timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept *
+ MSEC_PER_SEC);
+ if (smc_sk(nsk)->use_fallback) {
+ struct sock *clcsk = smc_sk(nsk)->clcsock->sk;
+
+ lock_sock(clcsk);
+ if (skb_queue_empty(&clcsk->sk_receive_queue))
+ sk_wait_data(clcsk, &timeo, NULL);
+ release_sock(clcsk);
+ } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) {
+ lock_sock(nsk);
+ smc_rx_wait_data(smc_sk(nsk), &timeo);
+ release_sock(nsk);
+ }
+ }
out:
- release_sock(sk);
sock_put(sk); /* sock_hold above */
return rc;
}
@@ -1337,6 +1358,9 @@ static int smc_setsockopt(struct socket
0);
}
break;
+ case TCP_DEFER_ACCEPT:
+ smc->sockopt_defer_accept = val;
+ break;
default:
break;
}
--- a/net/smc/smc.h
+++ b/net/smc/smc.h
@@ -179,6 +179,10 @@ struct smc_sock { /* smc sock contain
struct list_head accept_q; /* sockets to be accepted */
spinlock_t accept_q_lock; /* protects accept_q */
bool use_fallback; /* fallback to tcp */
+ int sockopt_defer_accept;
+ /* sockopt TCP_DEFER_ACCEPT
+ * value
+ */
u8 wait_close_tx_prepared : 1;
/* shutdown wr or close
* started, waiting for unsent
--- a/net/smc/smc_rx.c
+++ b/net/smc/smc_rx.c
@@ -50,7 +50,7 @@ static void smc_rx_data_ready(struct soc
* 1 if at least 1 byte available in rcvbuf or if socket error/shutdown.
* 0 otherwise (nothing in rcvbuf nor timeout, e.g. interrupted).
*/
-static int smc_rx_wait_data(struct smc_sock *smc, long *timeo)
+int smc_rx_wait_data(struct smc_sock *smc, long *timeo)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
struct smc_connection *conn = &smc->conn;
--- a/net/smc/smc_rx.h
+++ b/net/smc/smc_rx.h
@@ -19,5 +19,6 @@
void smc_rx_init(struct smc_sock *smc);
int smc_rx_recvmsg(struct smc_sock *smc, struct msghdr *msg, size_t len,
int flags);
+int smc_rx_wait_data(struct smc_sock *smc, long *timeo);
#endif /* SMC_RX_H */