[PATCH 8/8] net: mv643xx_eth: Avoid unmapping the TSO header buffers
From: Ezequiel Garcia <hidden>
Date: 2014-05-30 16:41:33
Subsystem:
marvell mv643xx ethernet driver, networking drivers, the rest · Maintainers:
Sebastian Hesselbarth, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
The buffers for the TSO headers belong to a DMA coherent region which is allocated at ndo_open() time, and released at ndo_stop() time. Therefore, and contrary to the TSO payload descriptor buffers, the TSO header buffers don't need to be unmapped. This commit adds a check to detect a TSO header buffer and explicitly prevent the unmap. Signed-off-by: Ezequiel Garcia <redacted> --- drivers/net/ethernet/marvell/mv643xx_eth.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/marvell/mv643xx_eth.c b/drivers/net/ethernet/marvell/mv643xx_eth.c
index 88afbe0..b151a94 100644
--- a/drivers/net/ethernet/marvell/mv643xx_eth.c
+++ b/drivers/net/ethernet/marvell/mv643xx_eth.c@@ -189,6 +189,9 @@ static char mv643xx_eth_driver_version[] = "1.4"; #define MV643XX_MAX_TSO_SEGS 100 #define MV643XX_MAX_SKB_DESCS (MV643XX_MAX_TSO_SEGS * 2 + MAX_SKB_FRAGS) +#define IS_TSO_HEADER(txq, addr) \ + ((addr >= txq->tso_hdrs_dma) && \ + (addr < txq->tso_hdrs_dma + txq->tx_ring_size * TSO_HEADER_SIZE)) /* * RX/TX descriptors. */
@@ -1072,8 +1075,9 @@ static int txq_reclaim(struct tx_queue *txq, int budget, int force) mp->dev->stats.tx_errors++; } - dma_unmap_single(mp->dev->dev.parent, desc->buf_ptr, - desc->byte_cnt, DMA_TO_DEVICE); + if (!IS_TSO_HEADER(txq, desc->buf_ptr)) + dma_unmap_single(mp->dev->dev.parent, desc->buf_ptr, + desc->byte_cnt, DMA_TO_DEVICE); dev_kfree_skb(skb); }
--
1.9.1