[patch 04/58] b43: Refresh RX poison on buffer recycling

Greg KH
2009-05-06T21:55:53Z

[-- Attachment #1: b43-refresh-rx-poison-on-buffer-recycling.patch --]
[-- Type: text/plain, Size: 2720 bytes --]

2.6.29-stable review patch. If anyone has any objections, please let us know.

------------------

From: Michael Buesch <mb@bu3sch.de>

upstream commit: cf68636a9773aa97915497fe54fa4a51e3f08f3a

The RX buffer poison needs to be refreshed, if we recycle an RX buffer,
because it might be (partially) overwritten by some DMA operations.

Cc: stable@kernel.org
Cc: Francesco Gringoli <francesco.gringoli@ing.unibs.it>
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
---
drivers/net/wireless/b43/dma.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

--- a/drivers/net/wireless/b43/dma.c
+++ b/drivers/net/wireless/b43/dma.c
@@ -1496,20 +1496,16 @@ static void dma_rx(struct b43_dmaring *r
len = le16_to_cpu(rxhdr->frame_len);
} while (len == 0 && i++ < 5);
if (unlikely(len == 0)) {
- /* recycle the descriptor buffer. */
- sync_descbuffer_for_device(ring, meta->dmaaddr,
- ring->rx_buffersize);
- goto drop;
+ 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");
- /* recycle the descriptor buffer. */
- sync_descbuffer_for_device(ring, meta->dmaaddr,
- ring->rx_buffersize);
- goto drop;
+ dmaaddr = meta->dmaaddr;
+ goto drop_recycle_buffer;
}
if (unlikely(len > ring->rx_buffersize)) {
/* The data did not fit into one descriptor buffer
@@ -1523,6 +1519,7 @@ static void dma_rx(struct b43_dmaring *r
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);
@@ -1541,8 +1538,7 @@ static void dma_rx(struct b43_dmaring *r
err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
if (unlikely(err)) {
b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
- sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
- goto drop;
+ goto drop_recycle_buffer;
}

unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
@@ -1552,6 +1548,11 @@ static void dma_rx(struct b43_dmaring *r
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);
}

void b43_dma_rx(struct b43_dmaring *ring)