vsock: add pkt cancel capability

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 9d24c0e958b18e614e30b24c0fcfbbe2152941f3..68675a151f22b8b63c02b25a67b833d9a6046d84 100644 (file)
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -213,6 +213,47 @@ virtio_transport_send_pkt(struct virtio_vsock_pkt *pkt)
        return len;
 }
 
+static int
+virtio_transport_cancel_pkt(struct vsock_sock *vsk)
+{
+       struct virtio_vsock *vsock;
+       struct virtio_vsock_pkt *pkt, *n;
+       int cnt = 0;
+       LIST_HEAD(freeme);
+
+       vsock = virtio_vsock_get();
+       if (!vsock) {
+               return -ENODEV;
+       }
+
+       spin_lock_bh(&vsock->send_pkt_list_lock);
+       list_for_each_entry_safe(pkt, n, &vsock->send_pkt_list, list) {
+               if (pkt->vsk != vsk)
+                       continue;
+               list_move(&pkt->list, &freeme);
+       }
+       spin_unlock_bh(&vsock->send_pkt_list_lock);
+
+       list_for_each_entry_safe(pkt, n, &freeme, list) {
+               if (pkt->reply)
+                       cnt++;
+               list_del(&pkt->list);
+               virtio_transport_free_pkt(pkt);
+       }
+
+       if (cnt) {
+               struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX];
+               int new_cnt;
+
+               new_cnt = atomic_sub_return(cnt, &vsock->queued_replies);
+               if (new_cnt + cnt >= virtqueue_get_vring_size(rx_vq) &&
+                   new_cnt < virtqueue_get_vring_size(rx_vq))
+                       queue_work(virtio_vsock_workqueue, &vsock->rx_work);
+       }
+
+       return 0;
+}
+
 static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
 {
        int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
@@ -462,6 +503,7 @@ static struct virtio_transport virtio_transport = {
                .release                  = virtio_transport_release,
                .connect                  = virtio_transport_connect,
                .shutdown                 = virtio_transport_shutdown,
+               .cancel_pkt               = virtio_transport_cancel_pkt,
 
                .dgram_bind               = virtio_transport_dgram_bind,
                .dgram_dequeue            = virtio_transport_dgram_dequeue,