Commit 07770616 authored by Arseniy Krasnov's avatar Arseniy Krasnov Committed by David S. Miller
Browse files

virtio/vsock: don't use skbuff state to account credit 



'skb->len' can vary when we partially read the data, this complicates the
calculation of credit to be updated in 'virtio_transport_inc_rx_pkt()/
virtio_transport_dec_rx_pkt()'.

Also in 'virtio_transport_dec_rx_pkt()' we were miscalculating the
credit since 'skb->len' was redundant.

For these reasons, let's replace the use of skbuff state to calculate new
'rx_bytes'/'fwd_cnt' values with explicit value as input argument. This
makes code more simple, because it is not needed to change skbuff state
before each call to update 'rx_bytes'/'fwd_cnt'.

Fixes: 71dc9ec9 ("virtio/vsock: replace virtio_vsock_pkt with sk_buff")
Signed-off-by: default avatarArseniy Krasnov <AVKrasnov@sberdevices.ru>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Acked-by: default avatarBobby Eshleman <bobby.eshleman@bytedance.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cd356010

net/vmw_vsock/virtio_transport_common.c

+11 −12
Original line number Diff line number Diff line
@@ -241,21 +241,18 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk, 
}



static bool virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,

					struct sk_buff *skb)

					u32 len)

{

	if (vvs->rx_bytes + skb->len > vvs->buf_alloc)

	if (vvs->rx_bytes + len > vvs->buf_alloc)

		return false;



	vvs->rx_bytes += skb->len;

	vvs->rx_bytes += len;

	return true;

}



static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,

					struct sk_buff *skb)

					u32 len)

{

	int len;



	len = skb_headroom(skb) - sizeof(struct virtio_vsock_hdr) - skb->len;

	vvs->rx_bytes -= len;

	vvs->fwd_cnt += len;

}
@@ -388,7 +385,9 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk, 
		skb_pull(skb, bytes);



		if (skb->len == 0) {

			virtio_transport_dec_rx_pkt(vvs, skb);

			u32 pkt_len = le32_to_cpu(virtio_vsock_hdr(skb)->len);



			virtio_transport_dec_rx_pkt(vvs, pkt_len);

			consume_skb(skb);

		} else {

			__skb_queue_head(&vvs->rx_queue, skb);
@@ -437,17 +436,17 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, 


	while (!msg_ready) {

		struct virtio_vsock_hdr *hdr;

		size_t pkt_len;



		skb = __skb_dequeue(&vvs->rx_queue);

		if (!skb)

			break;

		hdr = virtio_vsock_hdr(skb);

		pkt_len = (size_t)le32_to_cpu(hdr->len);



		if (dequeued_len >= 0) {

			size_t pkt_len;

			size_t bytes_to_copy;



			pkt_len = (size_t)le32_to_cpu(hdr->len);

			bytes_to_copy = min(user_buf_len, pkt_len);



			if (bytes_to_copy) {
@@ -484,7 +483,7 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, 
				msg->msg_flags |= MSG_EOR;

		}



		virtio_transport_dec_rx_pkt(vvs, skb);

		virtio_transport_dec_rx_pkt(vvs, pkt_len);

		kfree_skb(skb);

	}
@@ -1040,7 +1039,7 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk, 


	spin_lock_bh(&vvs->rx_lock);



	can_enqueue = virtio_transport_inc_rx_pkt(vvs, skb);

	can_enqueue = virtio_transport_inc_rx_pkt(vvs, len);

	if (!can_enqueue) {

		free_pkt = true;

		goto out;