net/mlx4_en: Fix pages never dma unmapped on rx

This patch fixes a bug introduced by commit 51151a16 (mlx4: allow
order-0 memory allocations in RX path).

dma_unmap_page never reached because condition to detect last fragment
in page is wrong. offset+frag_stride can't be greater than size, need to
make sure no additional frag will fit in page => compare offset +
frag_stride + next_frag_size instead.
next_frag_size is the same as the current one, since page is shared only
with frags of the same size.

CC: Eric Dumazet <edumazet@google.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Amir Vadai 2013-10-07 13:38:13 +02:00 committed by David S. Miller
parent 70fbe07943
commit 021f1107ff

View file

@ -135,9 +135,10 @@ static void mlx4_en_free_frag(struct mlx4_en_priv *priv,
int i)
{
const struct mlx4_en_frag_info *frag_info = &priv->frag_info[i];
u32 next_frag_end = frags[i].page_offset + 2 * frag_info->frag_stride;
if (frags[i].page_offset + frag_info->frag_stride >
frags[i].page_size)
if (next_frag_end > frags[i].page_size)
dma_unmap_page(priv->ddev, frags[i].dma, frags[i].page_size,
PCI_DMA_FROMDEVICE);