From e2370f07cf703c0920c99bc24de3d152262738f0 Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov Date: Wed, 15 Jul 2015 00:56:52 +0300 Subject: ravb: do not invalidate cache for RX buffer twice First, dma_sync_single_for_cpu() shouldn't have been called in the first place (it's a streaming DMA API), dma_unmap_single() should have been called instead. Second, dma_unmap_single() call after handing the buffer to napi_gro_receive() makes little sense. Moreover desc->dptr might not be valid at this point. Signed-off-by: Sergei Shtylyov Signed-off-by: David S. Miller --- drivers/net/ethernet/renesas/ravb_main.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) (limited to 'drivers/net/ethernet/renesas/ravb_main.c') diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index fd9745714d90..0e5fde321630 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -543,10 +543,9 @@ static bool ravb_rx(struct net_device *ndev, int *quota, int q) skb = priv->rx_skb[q][entry]; priv->rx_skb[q][entry] = NULL; - dma_sync_single_for_cpu(&ndev->dev, - le32_to_cpu(desc->dptr), - ALIGN(PKT_BUF_SZ, 16), - DMA_FROM_DEVICE); + dma_unmap_single(&ndev->dev, le32_to_cpu(desc->dptr), + ALIGN(PKT_BUF_SZ, 16), + DMA_FROM_DEVICE); get_ts &= (q == RAVB_NC) ? RAVB_RXTSTAMP_TYPE_V2_L2_EVENT : ~RAVB_RXTSTAMP_TYPE_V2_L2_EVENT; @@ -584,9 +583,6 @@ static bool ravb_rx(struct net_device *ndev, int *quota, int q) if (!skb) break; /* Better luck next round. */ ravb_set_buffer_align(skb); - dma_unmap_single(&ndev->dev, le32_to_cpu(desc->dptr), - ALIGN(PKT_BUF_SZ, 16), - DMA_FROM_DEVICE); dma_addr = dma_map_single(&ndev->dev, skb->data, le16_to_cpu(desc->ds_cc), DMA_FROM_DEVICE); -- cgit v1.2.3 From 06613e38f1f2b098d46e9549756c0d5c040f2ef8 Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov Date: Fri, 17 Jul 2015 00:28:38 +0300 Subject: ravb: fix race updating TCCR The TCCR.TSRQn bit may get clearead after TCCR gets read, so that TCCR write would get skipped. We don't need to check this bit before setting. Signed-off-by: Sergei Shtylyov Signed-off-by: David S. Miller --- drivers/net/ethernet/renesas/ravb_main.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'drivers/net/ethernet/renesas/ravb_main.c') diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 0e5fde321630..d08c250e843e 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -1275,7 +1275,6 @@ static netdev_tx_t ravb_start_xmit(struct sk_buff *skb, struct net_device *ndev) u32 dma_addr; void *buffer; u32 entry; - u32 tccr; spin_lock_irqsave(&priv->lock, flags); if (priv->cur_tx[q] - priv->dirty_tx[q] >= priv->num_tx_ring[q]) { @@ -1324,9 +1323,7 @@ static netdev_tx_t ravb_start_xmit(struct sk_buff *skb, struct net_device *ndev) dma_wmb(); desc->die_dt = DT_FSINGLE; - tccr = ravb_read(ndev, TCCR); - if (!(tccr & (TCCR_TSRQ0 << q))) - ravb_write(ndev, tccr | (TCCR_TSRQ0 << q), TCCR); + ravb_write(ndev, ravb_read(ndev, TCCR) | (TCCR_TSRQ0 << q), TCCR); priv->cur_tx[q]++; if (priv->cur_tx[q] - priv->dirty_tx[q] >= priv->num_tx_ring[q] && -- cgit v1.2.3 From d8b48911fd249bc1a3431a9515619403c96d6af3 Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov Date: Wed, 22 Jul 2015 01:31:59 +0300 Subject: ravb: fix ring memory allocation The driver is written as if it can adapt to a low memory situation allocating less RX skbs and TX aligned buffers than the respective RX/TX ring sizes. In reality though the driver would malfunction in this case. Stop being overly smart and just fail in such situation -- this is achieved by moving the memory allocation from ravb_ring_format() to ravb_ring_init(). We leave dma_map_single() calls in place but make their failure non-fatal by marking the corresponding RX descriptors with zero data size which should prevent DMA to an invalid addresses. Signed-off-by: Sergei Shtylyov Signed-off-by: David S. Miller --- drivers/net/ethernet/renesas/ravb_main.c | 59 ++++++++++++++++++-------------- 1 file changed, 34 insertions(+), 25 deletions(-) (limited to 'drivers/net/ethernet/renesas/ravb_main.c') diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index d08c250e843e..78849dd4ef8e 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -228,9 +228,7 @@ static void ravb_ring_format(struct net_device *ndev, int q) struct ravb_desc *desc = NULL; int rx_ring_size = sizeof(*rx_desc) * priv->num_rx_ring[q]; int tx_ring_size = sizeof(*tx_desc) * priv->num_tx_ring[q]; - struct sk_buff *skb; dma_addr_t dma_addr; - void *buffer; int i; priv->cur_rx[q] = 0; @@ -241,41 +239,28 @@ static void ravb_ring_format(struct net_device *ndev, int q) memset(priv->rx_ring[q], 0, rx_ring_size); /* Build RX ring buffer */ for (i = 0; i < priv->num_rx_ring[q]; i++) { - priv->rx_skb[q][i] = NULL; - skb = netdev_alloc_skb(ndev, PKT_BUF_SZ + RAVB_ALIGN - 1); - if (!skb) - break; - ravb_set_buffer_align(skb); /* RX descriptor */ rx_desc = &priv->rx_ring[q][i]; /* The size of the buffer should be on 16-byte boundary. */ rx_desc->ds_cc = cpu_to_le16(ALIGN(PKT_BUF_SZ, 16)); - dma_addr = dma_map_single(&ndev->dev, skb->data, + dma_addr = dma_map_single(&ndev->dev, priv->rx_skb[q][i]->data, ALIGN(PKT_BUF_SZ, 16), DMA_FROM_DEVICE); - if (dma_mapping_error(&ndev->dev, dma_addr)) { - dev_kfree_skb(skb); - break; - } - priv->rx_skb[q][i] = skb; + /* We just set the data size to 0 for a failed mapping which + * should prevent DMA from happening... + */ + if (dma_mapping_error(&ndev->dev, dma_addr)) + rx_desc->ds_cc = cpu_to_le16(0); rx_desc->dptr = cpu_to_le32(dma_addr); rx_desc->die_dt = DT_FEMPTY; } rx_desc = &priv->rx_ring[q][i]; rx_desc->dptr = cpu_to_le32((u32)priv->rx_desc_dma[q]); rx_desc->die_dt = DT_LINKFIX; /* type */ - priv->dirty_rx[q] = (u32)(i - priv->num_rx_ring[q]); memset(priv->tx_ring[q], 0, tx_ring_size); /* Build TX ring buffer */ for (i = 0; i < priv->num_tx_ring[q]; i++) { - priv->tx_skb[q][i] = NULL; - priv->tx_buffers[q][i] = NULL; - buffer = kmalloc(PKT_BUF_SZ + RAVB_ALIGN - 1, GFP_KERNEL); - if (!buffer) - break; - /* Aligned TX buffer */ - priv->tx_buffers[q][i] = buffer; tx_desc = &priv->tx_ring[q][i]; tx_desc->die_dt = DT_EEMPTY; } @@ -298,7 +283,10 @@ static void ravb_ring_format(struct net_device *ndev, int q) static int ravb_ring_init(struct net_device *ndev, int q) { struct ravb_private *priv = netdev_priv(ndev); + struct sk_buff *skb; int ring_size; + void *buffer; + int i; /* Allocate RX and TX skb rings */ priv->rx_skb[q] = kcalloc(priv->num_rx_ring[q], @@ -308,12 +296,28 @@ static int ravb_ring_init(struct net_device *ndev, int q) if (!priv->rx_skb[q] || !priv->tx_skb[q]) goto error; + for (i = 0; i < priv->num_rx_ring[q]; i++) { + skb = netdev_alloc_skb(ndev, PKT_BUF_SZ + RAVB_ALIGN - 1); + if (!skb) + goto error; + ravb_set_buffer_align(skb); + priv->rx_skb[q][i] = skb; + } + /* Allocate rings for the aligned buffers */ priv->tx_buffers[q] = kcalloc(priv->num_tx_ring[q], sizeof(*priv->tx_buffers[q]), GFP_KERNEL); if (!priv->tx_buffers[q]) goto error; + for (i = 0; i < priv->num_tx_ring[q]; i++) { + buffer = kmalloc(PKT_BUF_SZ + RAVB_ALIGN - 1, GFP_KERNEL); + if (!buffer) + goto error; + /* Aligned TX buffer */ + priv->tx_buffers[q][i] = buffer; + } + /* Allocate all RX descriptors. */ ring_size = sizeof(struct ravb_ex_rx_desc) * (priv->num_rx_ring[q] + 1); priv->rx_ring[q] = dma_alloc_coherent(NULL, ring_size, @@ -524,6 +528,10 @@ static bool ravb_rx(struct net_device *ndev, int *quota, int q) if (--boguscnt < 0) break; + /* We use 0-byte descriptors to mark the DMA mapping errors */ + if (!pkt_len) + continue; + if (desc_status & MSC_MC) stats->multicast++; @@ -587,10 +595,11 @@ static bool ravb_rx(struct net_device *ndev, int *quota, int q) le16_to_cpu(desc->ds_cc), DMA_FROM_DEVICE); skb_checksum_none_assert(skb); - if (dma_mapping_error(&ndev->dev, dma_addr)) { - dev_kfree_skb_any(skb); - break; - } + /* We just set the data size to 0 for a failed mapping + * which should prevent DMA from happening... + */ + if (dma_mapping_error(&ndev->dev, dma_addr)) + desc->ds_cc = cpu_to_le16(0); desc->dptr = cpu_to_le32(dma_addr); priv->rx_skb[q][entry] = skb; } -- cgit v1.2.3