[RFC PATCH v2 7/9] vsock: add API call for data ready

From: Arseniy Krasnov
Date: Mon Jul 25 2022 - 04:09:41 EST


This adds 'vsock_data_ready()' which must be called by transport to kick
sleeping data readers. It checks for SO_RCVLOWAT value before waking
user,thus preventing spurious wake ups.Based on 'tcp_data_ready()' logic.

Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
---
include/net/af_vsock.h | 1 +
net/vmw_vsock/af_vsock.c | 10 ++++++++++
2 files changed, 11 insertions(+)

diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index eae5874bae35..7b79fc5164cc 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -77,6 +77,7 @@ struct vsock_sock {
s64 vsock_stream_has_data(struct vsock_sock *vsk);
s64 vsock_stream_has_space(struct vsock_sock *vsk);
struct sock *vsock_create_connected(struct sock *parent);
+void vsock_data_ready(struct sock *sk);

/**** TRANSPORT ****/

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index b7a286db4af1..4b3ec3f9383f 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -882,6 +882,16 @@ s64 vsock_stream_has_space(struct vsock_sock *vsk)
}
EXPORT_SYMBOL_GPL(vsock_stream_has_space);

+void vsock_data_ready(struct sock *sk)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+
+ if (vsock_stream_has_data(vsk) >= sk->sk_rcvlowat ||
+ sock_flag(sk, SOCK_DONE))
+ sk->sk_data_ready(sk);
+}
+EXPORT_SYMBOL_GPL(vsock_data_ready);
+
static int vsock_release(struct socket *sock)
{
__vsock_release(sock->sk, 0);
--
2.25.1