[RFC PATCH v1 11/16] afvsock: add 'seqpacket_drop()'

[Arseny Krasnov]

Add special callback for SEQPACKET socket which is called when
we need to drop current in-progress record: part of record was
copied successfully, reader wait rest of record, but signal
interrupts it and reader leaves it's loop, leaving packets of
current record still in queue. So to avoid copy of "orphaned"
record, we tell transport to drop every packet until EOR will
be found.

Signed-off-by: Arseny Krasnov <arseny.krasnov@xxxxxxxxxxxxx>
---
 include/net/af_vsock.h   | 1 +
 net/vmw_vsock/af_vsock.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index 1747c0b564ef..356878aabbd4 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -141,6 +141,7 @@ struct vsock_transport {
 	int (*seqpacket_enqueue)(struct vsock_sock *vsk, struct msghdr *msg,
 				 size_t len);
 	bool (*seqpacket_allow)(u32 remote_cid);
+	void (*seqpacket_drop)(struct vsock_sock *vsk);
 
 	/* Notification. */
 	int (*notify_poll_in)(struct vsock_sock *, size_t, bool *);
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index ec54e4222cbf..27fa38090e13 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -2024,6 +2024,7 @@ static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg,
 		intr_err = vsock_connectible_wait_data(sk, &wait, timeout, NULL, 0);
 		if (intr_err <= 0) {
 			err = intr_err;
+			transport->seqpacket_drop(vsk);
 			break;
 		}
 
-- 
2.25.1