Merge remote-tracking branches 'asoc/fix/ak4671', 'asoc/fix/control', 'asoc/fix/da732...

[firefly-linux-kernel-4.4.55.git] / drivers / net / xen-netback / netback.c

diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
index f7a31d2cb3f1819fdf7ebdeb40e0f6bf44aabe0a..cab9f5257f577ffd03c3eb2b7e57398907ee3498 100644 (file)
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -655,9 +655,15 @@ static void xenvif_tx_err(struct xenvif_queue *queue,
        unsigned long flags;
 
        do {
+               int notify;
+
                spin_lock_irqsave(&queue->response_lock, flags);
                make_tx_response(queue, txp, XEN_NETIF_RSP_ERROR);
+               RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&queue->tx, notify);
                spin_unlock_irqrestore(&queue->response_lock, flags);
+               if (notify)
+                       notify_remote_via_irq(queue->tx_irq);
+
                if (cons == end)
                        break;
                txp = RING_GET_REQUEST(&queue->tx, cons++);
@@ -1343,7 +1349,7 @@ static int xenvif_handle_frag_list(struct xenvif_queue *queue, struct sk_buff *s
 {
        unsigned int offset = skb_headlen(skb);
        skb_frag_t frags[MAX_SKB_FRAGS];
-       int i;
+       int i, f;
        struct ubuf_info *uarg;
        struct sk_buff *nskb = skb_shinfo(skb)->frag_list;
 
@@ -1383,23 +1389,25 @@ static int xenvif_handle_frag_list(struct xenvif_queue *queue, struct sk_buff *s
                frags[i].page_offset = 0;
                skb_frag_size_set(&frags[i], len);
        }
-       /* swap out with old one */
-       memcpy(skb_shinfo(skb)->frags,
-              frags,
-              i * sizeof(skb_frag_t));
-       skb_shinfo(skb)->nr_frags = i;
-       skb->truesize += i * PAGE_SIZE;
 
-       /* remove traces of mapped pages and frag_list */
+       /* Copied all the bits from the frag list -- free it. */
        skb_frag_list_init(skb);
+       xenvif_skb_zerocopy_prepare(queue, nskb);
+       kfree_skb(nskb);
+
+       /* Release all the original (foreign) frags. */
+       for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
+               skb_frag_unref(skb, f);
        uarg = skb_shinfo(skb)->destructor_arg;
        /* increase inflight counter to offset decrement in callback */
        atomic_inc(&queue->inflight_packets);
        uarg->callback(uarg, true);
        skb_shinfo(skb)->destructor_arg = NULL;
 
-       xenvif_skb_zerocopy_prepare(queue, nskb);
-       kfree_skb(nskb);
+       /* Fill the skb with the new (local) frags. */
+       memcpy(skb_shinfo(skb)->frags, frags, i * sizeof(skb_frag_t));
+       skb_shinfo(skb)->nr_frags = i;
+       skb->truesize += i * PAGE_SIZE;
 
        return 0;
 }
@@ -1649,17 +1657,28 @@ static void xenvif_idx_release(struct xenvif_queue *queue, u16 pending_idx,
 {
        struct pending_tx_info *pending_tx_info;
        pending_ring_idx_t index;
+       int notify;
        unsigned long flags;
 
        pending_tx_info = &queue->pending_tx_info[pending_idx];
+
        spin_lock_irqsave(&queue->response_lock, flags);
+
        make_tx_response(queue, &pending_tx_info->req, status);
-       index = pending_index(queue->pending_prod);
+
+       /* Release the pending index before pusing the Tx response so
+        * its available before a new Tx request is pushed by the
+        * frontend.
+        */
+       index = pending_index(queue->pending_prod++);
        queue->pending_ring[index] = pending_idx;
-       /* TX shouldn't use the index before we give it back here */
-       mb();
-       queue->pending_prod++;
+
+       RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&queue->tx, notify);
+
        spin_unlock_irqrestore(&queue->response_lock, flags);
+
+       if (notify)
+               notify_remote_via_irq(queue->tx_irq);
 }
 
 
@@ -1669,7 +1688,6 @@ static void make_tx_response(struct xenvif_queue *queue,
 {
        RING_IDX i = queue->tx.rsp_prod_pvt;
        struct xen_netif_tx_response *resp;
-       int notify;
 
        resp = RING_GET_RESPONSE(&queue->tx, i);
        resp->id     = txp->id;
@@ -1679,9 +1697,6 @@ static void make_tx_response(struct xenvif_queue *queue,
                RING_GET_RESPONSE(&queue->tx, ++i)->status = XEN_NETIF_RSP_NULL;
 
        queue->tx.rsp_prod_pvt = ++i;
-       RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&queue->tx, notify);
-       if (notify)
-               notify_remote_via_irq(queue->tx_irq);
 }
 
 static struct xen_netif_rx_response *make_rx_response(struct xenvif_queue *queue,