1 files changed, 16 insertions, 14 deletions

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 01f4eb5c8b78..69fb225e59a6 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -36,7 +36,10 @@ module_param(csum, bool, 0444);
 module_param(gso, bool, 0444);
 
 /* FIXME: MTU in config. */
-#define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
+#define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
+#define MERGE_BUFFER_LEN (ALIGN(GOOD_PACKET_LEN + \
+                                sizeof(struct virtio_net_hdr_mrg_rxbuf), \
+                                L1_CACHE_BYTES))
 #define GOOD_COPY_LEN   128
 
 #define VIRTNET_DRIVER_VERSION "1.0.0"
@@ -314,10 +317,10 @@ static int receive_mergeable(struct receive_queue *rq, struct sk_buff *head_skb)
                         head_skb->dev->stats.rx_length_errors++;
                         return -EINVAL;
                 }
-                if (unlikely(len > MAX_PACKET_LEN)) {
+                if (unlikely(len > MERGE_BUFFER_LEN)) {
                         pr_debug("%s: rx error: merge buffer too long\n",
                                  head_skb->dev->name);
-                        len = MAX_PACKET_LEN;
+                        len = MERGE_BUFFER_LEN;
                 }
                 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
                         struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
@@ -336,18 +339,17 @@ static int receive_mergeable(struct receive_queue *rq, struct sk_buff *head_skb)
                 if (curr_skb != head_skb) {
                         head_skb->data_len += len;
                         head_skb->len += len;
-                        head_skb->truesize += MAX_PACKET_LEN;
+                        head_skb->truesize += MERGE_BUFFER_LEN;
                 }
                 page = virt_to_head_page(buf);
                 offset = buf - (char *)page_address(page);
                 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
                         put_page(page);
                         skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
-                                             len, MAX_PACKET_LEN);
+                                             len, MERGE_BUFFER_LEN);
                 } else {
                         skb_add_rx_frag(curr_skb, num_skb_frags, page,
-                                        offset, len,
-                                        MAX_PACKET_LEN);
+                                        offset, len, MERGE_BUFFER_LEN);
                 }
                 --rq->num;
         }
@@ -383,7 +385,7 @@ static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len)
                 struct page *page = virt_to_head_page(buf);
                 skb = page_to_skb(rq, page,
                                   (char *)buf - (char *)page_address(page),
-                                  len, MAX_PACKET_LEN);
+                                  len, MERGE_BUFFER_LEN);
                 if (unlikely(!skb)) {
                         dev->stats.rx_dropped++;
                         put_page(page);
@@ -471,11 +473,11 @@ static int add_recvbuf_small(struct receive_queue *rq, gfp_t gfp)
         struct skb_vnet_hdr *hdr;
         int err;
 
-        skb = __netdev_alloc_skb_ip_align(vi->dev, MAX_PACKET_LEN, gfp);
+        skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp);
         if (unlikely(!skb))
                 return -ENOMEM;
 
-        skb_put(skb, MAX_PACKET_LEN);
+        skb_put(skb, GOOD_PACKET_LEN);
 
         hdr = skb_vnet_hdr(skb);
         sg_set_buf(rq->sg, &hdr->hdr, sizeof hdr->hdr);
@@ -542,20 +544,20 @@ static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp)
         int err;
 
         if (gfp & __GFP_WAIT) {
-                if (skb_page_frag_refill(MAX_PACKET_LEN, &vi->alloc_frag,
+                if (skb_page_frag_refill(MERGE_BUFFER_LEN, &vi->alloc_frag,
                                          gfp)) {
                         buf = (char *)page_address(vi->alloc_frag.page) +
                               vi->alloc_frag.offset;
                         get_page(vi->alloc_frag.page);
-                        vi->alloc_frag.offset += MAX_PACKET_LEN;
+                        vi->alloc_frag.offset += MERGE_BUFFER_LEN;
                 }
         } else {
-                buf = netdev_alloc_frag(MAX_PACKET_LEN);
+                buf = netdev_alloc_frag(MERGE_BUFFER_LEN);
         }
         if (!buf)
                 return -ENOMEM;
 
-        sg_init_one(rq->sg, buf, MAX_PACKET_LEN);
+        sg_init_one(rq->sg, buf, MERGE_BUFFER_LEN);
         err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, buf, gfp);
         if (err < 0)
                 put_page(virt_to_head_page(buf));