static int setup_rx_descbuffer(struct b43_dmaring *ring,
struct b43_dmadesc_generic *desc,
struct b43_dmadesc_meta *meta, gfp_t gfp_flags)
{
dma_addr_t dmaaddr;
struct sk_buff *skb;
B43_WARN_ON(ring->tx);
skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
if (unlikely(!skb))
return -ENOMEM;
b43_poison_rx_buffer(ring, skb);
dmaaddr = map_descbuffer(ring, skb->data, ring->rx_buffersize, 0);
if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
/* ugh. try to realloc in zone_dma */
gfp_flags |= GFP_DMA;
dev_kfree_skb_any(skb);
skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
if (unlikely(!skb))
return -ENOMEM;
b43_poison_rx_buffer(ring, skb);
dmaaddr = map_descbuffer(ring, skb->data,
ring->rx_buffersize, 0);
if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
b43err(ring->dev->wl, "RX DMA buffer allocation failed\n");
dev_kfree_skb_any(skb);
return -EIO;
}
}
meta->skb = skb;
meta->dmaaddr = dmaaddr;
ring->ops->fill_descriptor(ring, desc, dmaaddr,
ring->rx_buffersize, 0, 0, 0);
return 0;
}
static void dma_rx(struct b43_dmaring *ring, int *slot)
{
const struct b43_dma_ops *ops = ring->ops;
struct b43_dmadesc_generic *desc;
struct b43_dmadesc_meta *meta;
struct b43_rxhdr_fw4 *rxhdr;
struct sk_buff *skb;
u16 len;
int err;
dma_addr_t dmaaddr;
desc = ops->idx2desc(ring, *slot, &meta);
sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
skb = meta->skb;
rxhdr = (struct b43_rxhdr_fw4 *)skb->data;
len = le16_to_cpu(rxhdr->frame_len);
if (len == 0) {
int i = 0;
do {
udelay(2);
barrier();
len = le16_to_cpu(rxhdr->frame_len);
} while (len == 0 && i++ < 5);
if (unlikely(len == 0)) {
dmaaddr = meta->dmaaddr;
goto drop_recycle_buffer;
}
}
if (unlikely(b43_rx_buffer_is_poisoned(ring, skb))) {
/* Something went wrong with the DMA.
* The device did not touch the buffer and did not overwrite the poison. */
b43dbg(ring->dev->wl, "DMA RX: Dropping poisoned buffer.\n");
dmaaddr = meta->dmaaddr;
goto drop_recycle_buffer;
}
if (unlikely(len + ring->frameoffset > ring->rx_buffersize)) {
/* The data did not fit into one descriptor buffer
* and is split over multiple buffers.
* This should never happen, as we try to allocate buffers
* big enough. So simply ignore this packet.
*/
int cnt = 0;
s32 tmp = len;
while (1) {
desc = ops->idx2desc(ring, *slot, &meta);
/* recycle the descriptor buffer. */
b43_poison_rx_buffer(ring, meta->skb);
sync_descbuffer_for_device(ring, meta->dmaaddr,
ring->rx_buffersize);
*slot = next_slot(ring, *slot);
cnt++;
tmp -= ring->rx_buffersize;
if (tmp <= 0)
break;
}
b43err(ring->dev->wl, "DMA RX buffer too small "
"(len: %u, buffer: %u, nr-dropped: %d)\n",
len, ring->rx_buffersize, cnt);
goto drop;
}
dmaaddr = meta->dmaaddr;
err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
if (unlikely(err)) {
b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
goto drop_recycle_buffer;
}
unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
skb_put(skb, len + ring->frameoffset);
skb_pull(skb, ring->frameoffset);
b43_rx(ring->dev, skb, rxhdr);
drop:
return;
drop_recycle_buffer:
/* Poison and recycle the RX buffer. */
b43_poison_rx_buffer(ring, skb);
sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
}
static void dma_rx(struct b43_dmaring *ring, int *slot)
{
const struct b43_dma_ops *ops = ring->ops;
struct b43_dmadesc_generic *desc;
struct b43_dmadesc_meta *meta;
struct b43_rxhdr_fw4 *rxhdr;
struct sk_buff *skb;
u16 len;
int err;
dma_addr_t dmaaddr;
desc = ops->idx2desc(ring, *slot, &meta);
sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
skb = meta->skb;
rxhdr = (struct b43_rxhdr_fw4 *)skb->data;
len = le16_to_cpu(rxhdr->frame_len);
if (len == 0) {
int i = 0;
do {
udelay(2);
barrier();
len = le16_to_cpu(rxhdr->frame_len);
} while (len == 0 && i++ < 5);
if (unlikely(len == 0)) {
dmaaddr = meta->dmaaddr;
goto drop_recycle_buffer;
}
}
if (unlikely(b43_rx_buffer_is_poisoned(ring, skb))) {
b43dbg(ring->dev->wl, "DMA RX: Dropping poisoned buffer.\n");
dmaaddr = meta->dmaaddr;
goto drop_recycle_buffer;
}
if (unlikely(len + ring->frameoffset > ring->rx_buffersize)) {
int cnt = 0;
s32 tmp = len;
while (1) {
desc = ops->idx2desc(ring, *slot, &meta);
b43_poison_rx_buffer(ring, meta->skb);
sync_descbuffer_for_device(ring, meta->dmaaddr,
ring->rx_buffersize);
*slot = next_slot(ring, *slot);
cnt++;
tmp -= ring->rx_buffersize;
if (tmp <= 0)
break;
}
b43err(ring->dev->wl, "DMA RX buffer too small "
"(len: %u, buffer: %u, nr-dropped: %d)\n",
len, ring->rx_buffersize, cnt);
goto drop;
}
dmaaddr = meta->dmaaddr;
err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
if (unlikely(err)) {
b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
goto drop_recycle_buffer;
}
unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
skb_put(skb, len + ring->frameoffset);
skb_pull(skb, ring->frameoffset);
b43_rx(ring->dev, skb, rxhdr);
drop:
return;
drop_recycle_buffer:
b43_poison_rx_buffer(ring, skb);
sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
}
