Do not return if transport callback for SO_RCVLOWAT is set (only in
error case). In this case we don't need to set 'sk_rcvlowat' field in
each transport - only in 'vsock_set_rcvlowat()'. Also, if 'sk_rcvlowat'
is now set only in af_vsock.c, change callback name from 'set_rcvlowat'
to 'notify_set_rcvlowat'.

Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
---
 Changelog:
 v3 -> v4:
  * Rename 'set_rcvlowat' to 'notify_set_rcvlowat'.
  * Commit message updated.

 include/net/af_vsock.h           | 2 +-
 net/vmw_vsock/af_vsock.c         | 9 +++++++--
 net/vmw_vsock/hyperv_transport.c | 4 ++--
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index e302c0e804d0..535701efc1e5 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -137,7 +137,6 @@ 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,
@@ -168,6 +167,7 @@ struct vsock_transport {
 		struct vsock_transport_send_notify_data *);
 	/* sk_lock held by the caller */
 	void (*notify_buffer_size)(struct vsock_sock *, u64 *);
+	int (*notify_set_rcvlowat)(struct vsock_sock *vsk, int val);
 
 	/* Shutdown. */
 	int (*shutdown)(struct vsock_sock *, int);
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 816725af281f..54ba7316f808 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -2264,8 +2264,13 @@ static int vsock_set_rcvlowat(struct sock *sk, int val)
 
 	transport = vsk->transport;
 
-	if (transport && transport->set_rcvlowat)
-		return transport->set_rcvlowat(vsk, val);
+	if (transport && transport->notify_set_rcvlowat) {
+		int err;
+
+		err = transport->notify_set_rcvlowat(vsk, val);
+		if (err)
+			return err;
+	}
 
 	WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
 	return 0;
diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
index 7cb1a9d2cdb4..e2157e387217 100644
--- a/net/vmw_vsock/hyperv_transport.c
+++ b/net/vmw_vsock/hyperv_transport.c
@@ -816,7 +816,7 @@ int hvs_notify_send_post_enqueue(struct vsock_sock *vsk, ssize_t written,
 }
 
 static
-int hvs_set_rcvlowat(struct vsock_sock *vsk, int val)
+int hvs_notify_set_rcvlowat(struct vsock_sock *vsk, int val)
 {
 	return -EOPNOTSUPP;
 }
@@ -856,7 +856,7 @@ static struct vsock_transport hvs_transport = {
 	.notify_send_pre_enqueue  = hvs_notify_send_pre_enqueue,
 	.notify_send_post_enqueue = hvs_notify_send_post_enqueue,
 
-	.set_rcvlowat             = hvs_set_rcvlowat
+	.notify_set_rcvlowat      = hvs_notify_set_rcvlowat
 };
 
 static bool hvs_check_transport(struct vsock_sock *vsk)
-- 
2.25.1

On Thu, Nov 30, 2023 at 12:25:17AM +0300, Arseniy Krasnov wrote:
>Do not return if transport callback for SO_RCVLOWAT is set (only in
>error case). In this case we don't need to set 'sk_rcvlowat' field in
>each transport - only in 'vsock_set_rcvlowat()'. Also, if 'sk_rcvlowat'
>is now set only in af_vsock.c, change callback name from 'set_rcvlowat'
>to 'notify_set_rcvlowat'.
>
>Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
>---
> Changelog:
> v3 -> v4:
>  * Rename 'set_rcvlowat' to 'notify_set_rcvlowat'.
>  * Commit message updated.

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

>
> include/net/af_vsock.h           | 2 +-
> net/vmw_vsock/af_vsock.c         | 9 +++++++--
> net/vmw_vsock/hyperv_transport.c | 4 ++--
> 3 files changed, 10 insertions(+), 5 deletions(-)
>
>diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
>index e302c0e804d0..535701efc1e5 100644
>--- a/include/net/af_vsock.h
>+++ b/include/net/af_vsock.h
>@@ -137,7 +137,6 @@ 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,
>@@ -168,6 +167,7 @@ struct vsock_transport {
> 		struct vsock_transport_send_notify_data *);
> 	/* sk_lock held by the caller */
> 	void (*notify_buffer_size)(struct vsock_sock *, u64 *);
>+	int (*notify_set_rcvlowat)(struct vsock_sock *vsk, int val);
>
> 	/* Shutdown. */
> 	int (*shutdown)(struct vsock_sock *, int);
>diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
>index 816725af281f..54ba7316f808 100644
>--- a/net/vmw_vsock/af_vsock.c
>+++ b/net/vmw_vsock/af_vsock.c
>@@ -2264,8 +2264,13 @@ static int vsock_set_rcvlowat(struct sock *sk, int val)
>
> 	transport = vsk->transport;
>
>-	if (transport && transport->set_rcvlowat)
>-		return transport->set_rcvlowat(vsk, val);
>+	if (transport && transport->notify_set_rcvlowat) {
>+		int err;
>+
>+		err = transport->notify_set_rcvlowat(vsk, val);
>+		if (err)
>+			return err;
>+	}
>
> 	WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
> 	return 0;
>diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
>index 7cb1a9d2cdb4..e2157e387217 100644
>--- a/net/vmw_vsock/hyperv_transport.c
>+++ b/net/vmw_vsock/hyperv_transport.c
>@@ -816,7 +816,7 @@ int hvs_notify_send_post_enqueue(struct vsock_sock *vsk, ssize_t written,
> }
>
> static
>-int hvs_set_rcvlowat(struct vsock_sock *vsk, int val)
>+int hvs_notify_set_rcvlowat(struct vsock_sock *vsk, int val)
> {
> 	return -EOPNOTSUPP;
> }
>@@ -856,7 +856,7 @@ static struct vsock_transport hvs_transport = {
> 	.notify_send_pre_enqueue  = hvs_notify_send_pre_enqueue,
> 	.notify_send_post_enqueue = hvs_notify_send_post_enqueue,
>
>-	.set_rcvlowat             = hvs_set_rcvlowat
>+	.notify_set_rcvlowat      = hvs_notify_set_rcvlowat
> };
>
> static bool hvs_check_transport(struct vsock_sock *vsk)
>-- 
>2.25.1
>