[RFC PATCH v4 09/17] vsock: enable SOCK_SUPPORT_ZC bit

[Arseniy Krasnov]

This bit is used by io_uring in case of zerocopy tx mode. io_uring code
checks, that socket has this feature. This patch sets it in two places:
1) For socket in 'connect()' call.
2) For new socket which is returned by 'accept()' call.

Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
---
 net/vmw_vsock/af_vsock.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 033006e1b5ad..da22ae0ef477 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1406,6 +1406,9 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
 			goto out;
 		}
 
+		if (vsock_msgzerocopy_allow(transport))
+			set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
+
 		err = vsock_auto_bind(vsk);
 		if (err)
 			goto out;
@@ -1560,6 +1563,9 @@ static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
 		} else {
 			newsock->state = SS_CONNECTED;
 			sock_graft(connected, newsock);
+			if (vsock_msgzerocopy_allow(vconnected->transport))
+				set_bit(SOCK_SUPPORT_ZC,
+					&connected->sk_socket->flags);
 		}
 
 		release_sock(connected);
-- 
2.25.1