static struct ftmac100_rxdes *
ftmac100_rx_locate_first_segment(struct ftmac100 *priv)
{
struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
while (!ftmac100_rxdes_owned_by_dma(rxdes)) {
if (ftmac100_rxdes_first_segment(rxdes))
return rxdes;
ftmac100_rxdes_set_dma_own(rxdes);
ftmac100_rx_pointer_advance(priv);
rxdes = ftmac100_current_rxdes(priv);
}
return NULL;
}
static void ftmac100_rx_drop_packet(struct ftmac100 *priv)
{
struct net_device *netdev = priv->netdev;
struct ftmac100_rxdes *rxdes = ftmac100_current_rxdes(priv);
bool done = false;
if (net_ratelimit())
netdev_dbg(netdev, "drop packet %p\n", rxdes);
do {
if (ftmac100_rxdes_last_segment(rxdes))
done = true;
ftmac100_rxdes_set_dma_own(rxdes);
ftmac100_rx_pointer_advance(priv);
rxdes = ftmac100_current_rxdes(priv);
} while (!done && !ftmac100_rxdes_owned_by_dma(rxdes));
netdev->stats.rx_dropped++;
}
static bool ftmac100_rx_packet(struct ftmac100 *priv, int *processed)
{
struct net_device *netdev = priv->netdev;
struct ftmac100_rxdes *rxdes;
struct sk_buff *skb;
struct page *page;
dma_addr_t map;
int length;
rxdes = ftmac100_rx_locate_first_segment(priv);
if (!rxdes)
return false;
if (unlikely(ftmac100_rx_packet_error(priv, rxdes))) {
ftmac100_rx_drop_packet(priv);
return true;
}
/*
* It is impossible to get multi-segment packets
* because we always provide big enough receive buffers.
*/
if (unlikely(!ftmac100_rxdes_last_segment(rxdes)))
BUG();
/* start processing */
skb = netdev_alloc_skb_ip_align(netdev, 128);
if (unlikely(!skb)) {
if (net_ratelimit())
netdev_err(netdev, "rx skb alloc failed\n");
ftmac100_rx_drop_packet(priv);
return true;
}
if (unlikely(ftmac100_rxdes_multicast(rxdes)))
netdev->stats.multicast++;
map = ftmac100_rxdes_get_dma_addr(rxdes);
dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
length = ftmac100_rxdes_frame_length(rxdes);
page = ftmac100_rxdes_get_page(rxdes);
skb_fill_page_desc(skb, 0, page, 0, length);
skb->len += length;
skb->data_len += length;
if (length > 128) {
skb->truesize += PAGE_SIZE;
/* We pull the minimum amount into linear part */
__pskb_pull_tail(skb, ETH_HLEN);
} else {
/* Small frames are copied into linear part to free one page */
__pskb_pull_tail(skb, length);
}
ftmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
ftmac100_rx_pointer_advance(priv);
skb->protocol = eth_type_trans(skb, netdev);
netdev->stats.rx_packets++;
netdev->stats.rx_bytes += skb->len;
/* push packet to protocol stack */
netif_receive_skb(skb);
(*processed)++;
return true;
}
static bool ftmac100_rx_packet(struct ftmac100 *priv, int *processed)
{
struct net_device *netdev = priv->netdev;
struct ftmac100_rxdes *rxdes;
struct sk_buff *skb;
struct page *page;
dma_addr_t map;
int length;
rxdes = ftmac100_rx_locate_first_segment(priv);
if (!rxdes)
return false;
if (unlikely(ftmac100_rx_packet_error(priv, rxdes))) {
ftmac100_rx_drop_packet(priv);
return true;
}
/*
*/
if (unlikely(!ftmac100_rxdes_last_segment(rxdes)))
BUG();
/* */
skb = netdev_alloc_skb_ip_align(netdev, 128);
if (unlikely(!skb)) {
if (net_ratelimit())
netdev_err(netdev, "rx skb alloc failed\n");
ftmac100_rx_drop_packet(priv);
return true;
}
if (unlikely(ftmac100_rxdes_multicast(rxdes)))
netdev->stats.multicast++;
map = ftmac100_rxdes_get_dma_addr(rxdes);
dma_unmap_page(priv->dev, map, RX_BUF_SIZE, DMA_FROM_DEVICE);
length = ftmac100_rxdes_frame_length(rxdes);
page = ftmac100_rxdes_get_page(rxdes);
skb_fill_page_desc(skb, 0, page, 0, length);
skb->len += length;
skb->data_len += length;
/* */
if (length > 64)
skb->truesize += PAGE_SIZE;
__pskb_pull_tail(skb, min(length, 64));
ftmac100_alloc_rx_page(priv, rxdes, GFP_ATOMIC);
ftmac100_rx_pointer_advance(priv);
skb->protocol = eth_type_trans(skb, netdev);
netdev->stats.rx_packets++;
netdev->stats.rx_bytes += skb->len;
/* */
netif_receive_skb(skb);
(*processed)++;
return true;
}