package/mac80211/patches/511-b43-refresh-rx-poison-on-buffer-recycling.patch

   1 The RX buffer poison needs to be refreshed, if we recycle an RX buffer,
   2 because it might be (partially) overwritten by some DMA operations.
   3
   4 Cc: stable@kernel.org
   5 Cc: Francesco Gringoli <francesco.gringoli@ing.unibs.it>
   6 Signed-off-by: Michael Buesch <mb@bu3sch.de>
   7
   8 ---
   9
  10 Index: compat-wireless-2009-03-31/drivers/net/wireless/b43/dma.c
  11 ===================================================================
  12 --- compat-wireless-2009-03-31.orig/drivers/net/wireless/b43/dma.c      2009-04-06 18:52:30.000000000 +0200
  13 +++ compat-wireless-2009-03-31/drivers/net/wireless/b43/dma.c   2009-04-06 18:53:04.000000000 +0200
  14 @@ -1503,20 +1503,16 @@ static void dma_rx(struct b43_dmaring *r
  15                         len = le16_to_cpu(rxhdr->frame_len);
  16                 } while (len == 0 && i++ < 5);
  17                 if (unlikely(len == 0)) {
  18 -                       /* recycle the descriptor buffer. */
  19 -                       sync_descbuffer_for_device(ring, meta->dmaaddr,
  20 -                                                  ring->rx_buffersize);
  21 -                       goto drop;
  22 +                       dmaaddr = meta->dmaaddr;
  23 +                       goto drop_recycle_buffer;
  24                 }
  25         }
  26         if (unlikely(b43_rx_buffer_is_poisoned(ring, skb))) {
  27                 /* Something went wrong with the DMA.
  28                  * The device did not touch the buffer and did not overwrite the poison. */
  29                 b43dbg(ring->dev->wl, "DMA RX: Dropping poisoned buffer.\n");
  30 -               /* recycle the descriptor buffer. */
  31 -               sync_descbuffer_for_device(ring, meta->dmaaddr,
  32 -                                          ring->rx_buffersize);
  33 -               goto drop;
  34 +               dmaaddr = meta->dmaaddr;
  35 +               goto drop_recycle_buffer;
  36         }
  37         if (unlikely(len > ring->rx_buffersize)) {
  38                 /* The data did not fit into one descriptor buffer
  39 @@ -1530,6 +1526,7 @@ static void dma_rx(struct b43_dmaring *r
  40                 while (1) {
  41                         desc = ops->idx2desc(ring, *slot, &meta);
  42                         /* recycle the descriptor buffer. */
  43 +                       b43_poison_rx_buffer(ring, meta->skb);
  44                         sync_descbuffer_for_device(ring, meta->dmaaddr,
  45                                                    ring->rx_buffersize);
  46                         *slot = next_slot(ring, *slot);
  47 @@ -1548,8 +1545,7 @@ static void dma_rx(struct b43_dmaring *r
  48         err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
  49         if (unlikely(err)) {
  50                 b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
  51 -               sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
  52 -               goto drop;
  53 +               goto drop_recycle_buffer;
  54         }
  55
  56         unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
  57 @@ -1559,6 +1555,11 @@ static void dma_rx(struct b43_dmaring *r
  58         b43_rx(ring->dev, skb, rxhdr);
  59  drop:
  60         return;
  61 +
  62 +drop_recycle_buffer:
  63 +       /* Poison and recycle the RX buffer. */
  64 +       b43_poison_rx_buffer(ring, skb);
  65 +       sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
  66  }
  67
  68  void b43_dma_rx(struct b43_dmaring *ring)