On Fri, Sep 22, 2023 at 08:24:24AM +0300, Arseniy Krasnov wrote:
For AF_VSOCK, zerocopy tx mode depends on transport, so this option must
be set in AF_VSOCK implementation where transport is accessible (if
transport is not set during setting SO_ZEROCOPY: for example socket is
not connected, then SO_ZEROCOPY will be enabled, but once transport will
be assigned, support of this type of transmission will be checked).
To handle SO_ZEROCOPY, AF_VSOCK implementation uses SOCK_CUSTOM_SOCKOPT
bit, thus handling SOL_SOCKET option operations, but all of them except
SO_ZEROCOPY will be forwarded to the generic handler by calling
'sock_setsockopt()'.
Signed-off-by: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxxxxx>
---
Changelog:
v5(big patchset) -> v1:
* Compact 'if' conditions.
* Rename 'zc_val' to 'zerocopy'.
* Use 'zerocopy' value directly in 'sock_valbool_flag()', without
?: operator.
* Set 'SOCK_CUSTOM_SOCKOPT' bit for connectible sockets only, as
suggested by Bobby Eshleman <bobbyeshleman@xxxxxxxxx>.
net/vmw_vsock/af_vsock.c | 46 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 44 insertions(+), 2 deletions(-)
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 482300eb88e0..c05a42e02a17 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1406,8 +1406,16 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr,
goto out;
}
- if (vsock_msgzerocopy_allow(transport))
+ if (vsock_msgzerocopy_allow(transport)) {
set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
+ } else if (sock_flag(sk, SOCK_ZEROCOPY)) {
+ /* If this option was set before 'connect()',
+ * when transport was unknown, check that this
+ * feature is supported here.
+ */
+ err = -EOPNOTSUPP;
+ goto out;
+ }
err = vsock_auto_bind(vsk);
if (err)
@@ -1643,7 +1651,7 @@ static int vsock_connectible_setsockopt(struct socket *sock,
const struct vsock_transport *transport;
u64 val;
- if (level != AF_VSOCK)
+ if (level != AF_VSOCK && level != SOL_SOCKET)
return -ENOPROTOOPT;
#define COPY_IN(_v) \
@@ -1666,6 +1674,34 @@ static int vsock_connectible_setsockopt(struct socket *sock,
transport = vsk->transport;
+ if (level == SOL_SOCKET) {
+ int zerocopy;
+
+ if (optname != SO_ZEROCOPY) {
+ release_sock(sk);
+ return sock_setsockopt(sock, level, optname, optval, optlen);
+ }
+
+ /* Use 'int' type here, because variable to
+ * set this option usually has this type.
+ */
+ COPY_IN(zerocopy);
+
+ if (zerocopy < 0 || zerocopy > 1) {
+ err = -EINVAL;
+ goto exit;
+ }
+
+ if (transport && !vsock_msgzerocopy_allow(transport)) {
+ err = -EOPNOTSUPP;
+ goto exit;
+ }
+
+ sock_valbool_flag(sk, SOCK_ZEROCOPY,
+ zerocopy);
it's not necessary to wrap this call.
+ goto exit;
+ }
+
switch (optname) {
case SO_VM_SOCKETS_BUFFER_SIZE:
COPY_IN(val);
@@ -2322,6 +2358,12 @@ static int vsock_create(struct net *net, struct socket *sock,
}
}
+ /* SOCK_DGRAM doesn't have 'setsockopt' callback set in its
+ * proto_ops, so there is no handler for custom logic.
+ */
+ if (sock_type_connectible(sock->type))
+ set_bit(SOCK_CUSTOM_SOCKOPT, &sk->sk_socket->flags);
+
vsock_insert_unbound(vsk);
return 0;
--
2.25.1
