From e38f22c860edb7804b4722ac2332f7c51b9c6b72 Mon Sep 17 00:00:00 2001 From: Arseniy Krasnov Date: Fri, 19 Aug 2022 05:25:19 +0000 Subject: [PATCH] vsock: SO_RCVLOWAT transport set callback This adds transport specific callback for SO_RCVLOWAT, because in some transports it may be difficult to know current available number of bytes ready to read. Thus, when SO_RCVLOWAT is set, transport may reject it. Signed-off-by: Arseniy Krasnov Signed-off-by: Paolo Abeni --- include/net/af_vsock.h | 1 + net/vmw_vsock/af_vsock.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index 1c53c4c4d88f..d609a088cb27 100644 --- a/include/net/af_vsock.h +++ b/include/net/af_vsock.h @@ -135,6 +135,7 @@ struct vsock_transport { u64 (*stream_rcvhiwat)(struct vsock_sock *); bool (*stream_is_active)(struct vsock_sock *); bool (*stream_allow)(u32 cid, u32 port); + int (*set_rcvlowat)(struct vsock_sock *vsk, int val); /* SEQ_PACKET. */ ssize_t (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index b4ee163154a6..07c8f74a821f 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -2137,6 +2137,25 @@ out: return err; } +static int vsock_set_rcvlowat(struct sock *sk, int val) +{ + const struct vsock_transport *transport; + struct vsock_sock *vsk; + + vsk = vsock_sk(sk); + + if (val > vsk->buffer_size) + return -EINVAL; + + transport = vsk->transport; + + if (transport && transport->set_rcvlowat) + return transport->set_rcvlowat(vsk, val); + + WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); + return 0; +} + static const struct proto_ops vsock_stream_ops = { .family = PF_VSOCK, .owner = THIS_MODULE, @@ -2156,6 +2175,7 @@ static const struct proto_ops vsock_stream_ops = { .recvmsg = vsock_connectible_recvmsg, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage, + .set_rcvlowat = vsock_set_rcvlowat, }; static const struct proto_ops vsock_seqpacket_ops = { -- 2.11.0