From 18c21467b2162107891f15ce1da4350b4e7016a3 Mon Sep 17 00:00:00 2001 From: Ioana Radulescu Date: Fri, 8 Dec 2017 06:47:57 -0600 Subject: [PATCH] staging: fsl-dpaa2/eth: Compute needed headroom per frame For non-linear skbs we build scatter-gather frames and allocate a new buffer for the S/G table in which we reserve the required headroom, so the actual skb headroom size doesn't matter. Rather than use a one-size-fits-all approach, decide when to enforce headroom requirements on a frame by frame basis. Signed-off-by: Ioana Radulescu Signed-off-by: Greg Kroah-Hartman --- drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c | 9 ++++++--- drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.h | 11 ++++++++--- 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c b/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c index 2c12859d3ff0..8edb7c10f978 100644 --- a/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c +++ b/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c @@ -437,7 +437,8 @@ static int build_single_fd(struct dpaa2_eth_priv *priv, struct sk_buff **skbh; dma_addr_t addr; - buffer_start = PTR_ALIGN(skb->data - dpaa2_eth_needed_headroom(priv), + buffer_start = PTR_ALIGN(skb->data - + dpaa2_eth_needed_headroom(priv, skb), DPAA2_ETH_TX_BUF_ALIGN); /* Store a backpointer to the skb at the beginning of the buffer @@ -532,15 +533,17 @@ static netdev_tx_t dpaa2_eth_tx(struct sk_buff *skb, struct net_device *net_dev) struct dpaa2_eth_drv_stats *percpu_extras; struct dpaa2_eth_fq *fq; u16 queue_mapping; + unsigned int needed_headroom; int err, i; percpu_stats = this_cpu_ptr(priv->percpu_stats); percpu_extras = this_cpu_ptr(priv->percpu_extras); - if (skb_headroom(skb) < dpaa2_eth_needed_headroom(priv)) { + needed_headroom = dpaa2_eth_needed_headroom(priv, skb); + if (skb_headroom(skb) < needed_headroom) { struct sk_buff *ns; - ns = skb_realloc_headroom(skb, dpaa2_eth_needed_headroom(priv)); + ns = skb_realloc_headroom(skb, needed_headroom); if (unlikely(!ns)) { percpu_stats->tx_dropped++; goto err_alloc_headroom; diff --git a/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.h b/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.h index 546a8624ac2f..4ea41d85c231 100644 --- a/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.h +++ b/drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.h @@ -364,9 +364,13 @@ static inline unsigned int dpaa2_eth_buf_raw_size(struct dpaa2_eth_priv *priv) } static inline -unsigned int dpaa2_eth_needed_headroom(struct dpaa2_eth_priv *priv) +unsigned int dpaa2_eth_needed_headroom(struct dpaa2_eth_priv *priv, + struct sk_buff *skb) { - return priv->tx_data_offset + DPAA2_ETH_TX_BUF_ALIGN; + if (skb_is_nonlinear(skb)) + return 0; + + return DPAA2_ETH_SWA_SIZE + DPAA2_ETH_TX_BUF_ALIGN; } /* Extra headroom space requested to hardware, in order to make sure there's @@ -374,7 +378,8 @@ unsigned int dpaa2_eth_needed_headroom(struct dpaa2_eth_priv *priv) */ static inline unsigned int dpaa2_eth_rx_head_room(struct dpaa2_eth_priv *priv) { - return dpaa2_eth_needed_headroom(priv) - DPAA2_ETH_RX_HWA_SIZE; + return priv->tx_data_offset + DPAA2_ETH_TX_BUF_ALIGN - + DPAA2_ETH_RX_HWA_SIZE; } static int dpaa2_eth_queue_count(struct dpaa2_eth_priv *priv)