ipv4: add ip_sock_set_mtu_discover

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

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com> [rxrpc bits]
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Christoph Hellwig 2020-05-28 07:12:29 +02:00 committed by David S. Miller
parent db45c0ef25
commit 2de569bda2
4 changed files with 18 additions and 16 deletions

View File

@ -766,6 +766,7 @@ static inline bool inetdev_valid_mtu(unsigned int mtu)
}
void ip_sock_set_freebind(struct sock *sk);
int ip_sock_set_mtu_discover(struct sock *sk, int val);
void ip_sock_set_recverr(struct sock *sk);
void ip_sock_set_tos(struct sock *sk, int val);

View File

@ -597,6 +597,17 @@ void ip_sock_set_recverr(struct sock *sk)
}
EXPORT_SYMBOL(ip_sock_set_recverr);
int ip_sock_set_mtu_discover(struct sock *sk, int val)
{
if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
return -EINVAL;
lock_sock(sk);
inet_sk(sk)->pmtudisc = val;
release_sock(sk);
return 0;
}
EXPORT_SYMBOL(ip_sock_set_mtu_discover);
/*
* Socket option code for IP. This is the end of the line after any
* TCP,UDP etc options on an IP socket.

View File

@ -174,13 +174,7 @@ static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
ip_sock_set_recverr(local->socket->sk);
/* we want to set the don't fragment bit */
opt = IP_PMTUDISC_DO;
ret = kernel_setsockopt(local->socket, SOL_IP, IP_MTU_DISCOVER,
(char *) &opt, sizeof(opt));
if (ret < 0) {
_debug("setsockopt failed");
goto error;
}
ip_sock_set_mtu_discover(local->socket->sk, IP_PMTUDISC_DO);
/* We want receive timestamps. */
sock_enable_timestamps(local->socket->sk);

View File

@ -321,7 +321,7 @@ int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
struct kvec iov[2];
rxrpc_serial_t serial;
size_t len;
int ret, opt;
int ret;
_enter(",{%d}", skb->len);
@ -473,18 +473,14 @@ send_fragmentable:
switch (conn->params.local->srx.transport.family) {
case AF_INET6:
case AF_INET:
opt = IP_PMTUDISC_DONT;
kernel_setsockopt(conn->params.local->socket,
SOL_IP, IP_MTU_DISCOVER,
(char *)&opt, sizeof(opt));
ip_sock_set_mtu_discover(conn->params.local->socket->sk,
IP_PMTUDISC_DONT);
ret = kernel_sendmsg(conn->params.local->socket, &msg,
iov, 2, len);
conn->params.peer->last_tx_at = ktime_get_seconds();
opt = IP_PMTUDISC_DO;
kernel_setsockopt(conn->params.local->socket,
SOL_IP, IP_MTU_DISCOVER,
(char *)&opt, sizeof(opt));
ip_sock_set_mtu_discover(conn->params.local->socket->sk,
IP_PMTUDISC_DO);
break;
default: