1 files changed, 29 insertions, 19 deletions

diff --git a/vu_common.c b/vu_common.c
index b13b7c3..5f2ce18 100644
--- a/vu_common.c
+++ b/vu_common.c
@@ -76,13 +76,13 @@ void vu_init_elem(struct vu_virtq_element *elem, struct iovec *iov, int elem_cnt
  * 			in the in_sg array.
  * @max_elem:		Number of virtqueue elements in the array
  * @size:		Maximum size of the data in the frame
- * @frame_size:		The total size of the buffers (output)
+ * @collected:		Collected buffer length, up to @size, set on return
  *
  * Return: number of elements used to contain the frame
  */
 int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq,
 	       struct vu_virtq_element *elem, int max_elem,
-	       size_t size, size_t *frame_size)
+	       size_t size, size_t *collected)
 {
 	size_t current_size = 0;
 	int elem_cnt = 0;
@@ -113,25 +113,24 @@ int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq,
 			break;
 	}
 
-	if (frame_size)
-		*frame_size = current_size;
+	if (collected)
+		*collected = current_size;
 
 	return elem_cnt;
 }
 
 /**
  * vu_set_vnethdr() - set virtio-net headers
- * @vdev:		vhost-user device
  * @vnethdr:		Address of the header to set
  * @num_buffers:	Number of guest buffers of the frame
  */
-void vu_set_vnethdr(const struct vu_dev *vdev,
-		    struct virtio_net_hdr_mrg_rxbuf *vnethdr,
-		    int num_buffers)
+void vu_set_vnethdr(struct virtio_net_hdr_mrg_rxbuf *vnethdr, int num_buffers)
 {
 	vnethdr->hdr = VU_HEADER;
-	if (vu_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
-		vnethdr->num_buffers = htole16(num_buffers);
+	/* Note: if VIRTIO_NET_F_MRG_RXBUF is not negotiated,
+	 * num_buffers must be 1
+	 */
+	vnethdr->num_buffers = htole16(num_buffers);
 }
 
 /**
@@ -261,7 +260,7 @@ int vu_send_single(const struct ctx *c, const void *buf, size_t size)
 
 	vu_init_elem(elem, in_sg, VIRTQUEUE_MAX_SIZE);
 
-	size += sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	size += VNET_HLEN;
 	elem_cnt = vu_collect(vdev, vq, elem, VIRTQUEUE_MAX_SIZE, size, &total);
 	if (total < size) {
 		debug("vu_send_single: no space to send the data "
@@ -269,18 +268,15 @@ int vu_send_single(const struct ctx *c, const void *buf, size_t size)
 		goto err;
 	}
 
-	vu_set_vnethdr(vdev, in_sg[0].iov_base, elem_cnt);
+	vu_set_vnethdr(in_sg[0].iov_base, elem_cnt);
 
-	total -= sizeof(struct virtio_net_hdr_mrg_rxbuf);
+	total -= VNET_HLEN;
 
 	/* copy data from the buffer to the iovec */
-	iov_from_buf(in_sg, elem_cnt, sizeof(struct virtio_net_hdr_mrg_rxbuf),
-		     buf, total);
+	iov_from_buf(in_sg, elem_cnt, VNET_HLEN, buf, total);
 
-	if (*c->pcap) {
-		pcap_iov(in_sg, elem_cnt,
-			 sizeof(struct virtio_net_hdr_mrg_rxbuf));
-	}
+	if (*c->pcap)
+		pcap_iov(in_sg, elem_cnt, VNET_HLEN);
 
 	vu_flush(vdev, vq, elem, elem_cnt);
 
@@ -293,3 +289,17 @@ err:
 
 	return -1;
 }
+
+/**
+ * vu_pad() - Pad 802.3 frame to minimum length (60 bytes) if needed
+ * @iov:	Buffer in iovec array where end of 802.3 frame is stored
+ * @l2len:	Layer-2 length already filled in frame
+ */
+void vu_pad(struct iovec *iov, size_t l2len)
+{
+	if (l2len >= ETH_ZLEN)
+		return;
+
+	memset((char *)iov->iov_base + iov->iov_len, 0, ETH_ZLEN - l2len);
+	iov->iov_len += ETH_ZLEN - l2len;
+}