1 files changed, 21 insertions, 4 deletions

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 4a105006ca63..765c2d6358da 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -48,8 +48,16 @@ module_param(gso, bool, 0444);
  */
 DECLARE_EWMA(pkt_len, 1, 64)
 
+/* With mergeable buffers we align buffer address and use the low bits to
+ * encode its true size. Buffer size is up to 1 page so we need to align to
+ * square root of page size to ensure we reserve enough bits to encode the true
+ * size.
+ */
+#define MERGEABLE_BUFFER_MIN_ALIGN_SHIFT ((PAGE_SHIFT + 1) / 2)
+
 /* Minimum alignment for mergeable packet buffers. */
-#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256)
+#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, \
+                                   1 << MERGEABLE_BUFFER_MIN_ALIGN_SHIFT)
 
 #define VIRTNET_DRIVER_VERSION "1.0.0"
 
@@ -1104,7 +1112,7 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
                 hdr = skb_vnet_hdr(skb);
 
         if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
-                                    virtio_is_little_endian(vi->vdev)))
+                                    virtio_is_little_endian(vi->vdev), false))
                 BUG();
 
         if (vi->mergeable_rx_bufs)
@@ -1707,6 +1715,11 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog)
         u16 xdp_qp = 0, curr_qp;
         int i, err;
 
+        if (prog && prog->xdp_adjust_head) {
+                netdev_warn(dev, "Does not support bpf_xdp_adjust_head()\n");
+                return -EOPNOTSUPP;
+        }
+
         if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
             virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
             virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
@@ -1890,8 +1903,12 @@ static void free_receive_page_frags(struct virtnet_info *vi)
                         put_page(vi->rq[i].alloc_frag.page);
 }
 
-static bool is_xdp_queue(struct virtnet_info *vi, int q)
+static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
 {
+        /* For small receive mode always use kfree_skb variants */
+        if (!vi->mergeable_rx_bufs)
+                return false;
+
         if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
                 return false;
         else if (q < vi->curr_queue_pairs)
@@ -1908,7 +1925,7 @@ static void free_unused_bufs(struct virtnet_info *vi)
         for (i = 0; i < vi->max_queue_pairs; i++) {
                 struct virtqueue *vq = vi->sq[i].vq;
                 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
-                        if (!is_xdp_queue(vi, i))
+                        if (!is_xdp_raw_buffer_queue(vi, i))
                                 dev_kfree_skb(buf);
                         else
                                 put_page(virt_to_head_page(buf));