[PATCH 09/33] net: add sock_set_keepalive

From: Christoph Hellwig
Date: Wed May 20 2020 - 16:00:25 EST


Add a helper to directly set the SO_KEEPALIVE sockopt from kernel space
without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/dlm/lowcomms.c | 6 +-----
include/net/sock.h | 1 +
net/core/sock.c | 10 ++++++++++
net/rds/tcp_listen.c | 6 +-----
net/sunrpc/xprtsock.c | 4 +---
5 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index b79711d0aac72..b6e6dba281547 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -1142,11 +1142,7 @@ static struct socket *tcp_create_listen_sock(struct connection *con,
con->sock = NULL;
goto create_out;
}
- result = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
- (char *)&one, sizeof(one));
- if (result < 0) {
- log_print("Set keepalive failed: %d", result);
- }
+ sock_set_keepalive(sock->sk);

result = sock->ops->listen(sock, 5);
if (result < 0) {
diff --git a/include/net/sock.h b/include/net/sock.h
index 99ef43508d2b5..dc08c176238fd 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2691,6 +2691,7 @@ void sock_def_readable(struct sock *sk);
int sock_bindtoindex(struct sock *sk, int ifindex);
void sock_enable_timestamps(struct sock *sk);
void sock_no_linger(struct sock *sk);
+void sock_set_keepalive(struct sock *sk);
void sock_set_priority(struct sock *sk, u32 priority);
void sock_set_reuseaddr(struct sock *sk);
void sock_set_sndtimeo(struct sock *sk, s64 secs);
diff --git a/net/core/sock.c b/net/core/sock.c
index e4a4dd2b3d8b3..728f5fb156a0c 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -779,6 +779,16 @@ void sock_enable_timestamps(struct sock *sk)
}
EXPORT_SYMBOL(sock_enable_timestamps);

+void sock_set_keepalive(struct sock *sk)
+{
+ lock_sock(sk);
+ if (sk->sk_prot->keepalive)
+ sk->sk_prot->keepalive(sk, true);
+ sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
+ release_sock(sk);
+}
+EXPORT_SYMBOL(sock_set_keepalive);
+
/*
* This is meant for all protocols to use and covers goings on
* at the socket level. Everything here is generic.
diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c
index bbb31b9c0b391..d8bd132769594 100644
--- a/net/rds/tcp_listen.c
+++ b/net/rds/tcp_listen.c
@@ -43,13 +43,9 @@ int rds_tcp_keepalive(struct socket *sock)
/* values below based on xs_udp_default_timeout */
int keepidle = 5; /* send a probe 'keepidle' secs after last data */
int keepcnt = 5; /* number of unack'ed probes before declaring dead */
- int keepalive = 1;
int ret = 0;

- ret = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
- (char *)&keepalive, sizeof(keepalive));
- if (ret < 0)
- goto bail;
+ sock_set_keepalive(sock->sk);

ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT,
(char *)&keepcnt, sizeof(keepcnt));
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 845d0be805ece..30082cd039960 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -2110,7 +2110,6 @@ static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
unsigned int keepidle;
unsigned int keepcnt;
- unsigned int opt_on = 1;
unsigned int timeo;

spin_lock(&xprt->transport_lock);
@@ -2122,8 +2121,7 @@ static void xs_tcp_set_socket_timeouts(struct rpc_xprt *xprt,
spin_unlock(&xprt->transport_lock);

/* TCP Keepalive options */
- kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
- (char *)&opt_on, sizeof(opt_on));
+ sock_set_keepalive(sock->sk);
kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
(char *)&keepidle, sizeof(keepidle));
kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
--
2.26.2