ftgmac100: Drop support for fragmented receive

We don't support jumbo frames, we will never receive a
fragmented packet, the RX buffer is always big enough,
if not then it's a runaway packet that can be dropped.

So take out the loop that handles such things in
ftgmac100_rx_packet() which will help with subsequent
simplifications and improvements to the RX path

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index 298f6f0da0d2f4d099c3d8f6946a023d6dee4840..1c2093c53157cb9f36419143ec323b2c98173e54 100644 (file)
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -534,13 +534,19 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed)
        struct net_device *netdev = priv->netdev;
        struct ftgmac100_rxdes *rxdes;
        struct sk_buff *skb;
-       bool done = false;
+       struct page *page;
+       unsigned int size;
+       dma_addr_t map;
 
        rxdes = ftgmac100_rx_locate_first_segment(priv);
        if (!rxdes)
                return false;
 
-       if (unlikely(ftgmac100_rx_packet_error(priv, rxdes))) {
+       /* We don't support segmented rx frames, so drop these
+        * along with packets with errors.
+        */
+       if (unlikely(!ftgmac100_rxdes_last_segment(rxdes) ||
+                    ftgmac100_rx_packet_error(priv, rxdes))) {
                ftgmac100_rx_drop_packet(priv);
                return true;
        }
@@ -567,28 +573,21 @@ static bool ftgmac100_rx_packet(struct ftgmac100 *priv, int *processed)
            (ftgmac100_rxdes_is_udp(rxdes) && !ftgmac100_rxdes_udpcs_err(rxdes)))
                skb->ip_summed = CHECKSUM_UNNECESSARY;
 
-       do {
-               dma_addr_t map = ftgmac100_rxdes_get_dma_addr(rxdes);
-               struct page *page = ftgmac100_rxdes_get_page(priv, rxdes);
-               unsigned int size;
+       map = ftgmac100_rxdes_get_dma_addr(rxdes);
 
-               dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
-
-               size = ftgmac100_rxdes_data_length(rxdes);
-               skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, page, 0, size);
+       dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
 
-               skb->len += size;
-               skb->data_len += size;
-               skb->truesize += PAGE_SIZE;
+       size = ftgmac100_rxdes_data_length(rxdes);
+       skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, page, 0, size);
 
-               if (ftgmac100_rxdes_last_segment(rxdes))
-                       done = true;
+       skb->len += size;
+       skb->data_len += size;
+       skb->truesize += PAGE_SIZE;
 
-               ftgmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
+       ftgmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
 
-               ftgmac100_rx_pointer_advance(priv);
-               rxdes = ftgmac100_current_rxdes(priv);
-       } while (!done);
+       ftgmac100_rx_pointer_advance(priv);
+       rxdes = ftgmac100_current_rxdes(priv);
 
        /* Small frames are copied into linear part of skb to free one page */
        if (skb->len <= 128) {