From d6bf31431b533629ad65feb954c29bbf5696e490 Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 8 Jul 2014 00:23:19 +0100 Subject: [PATCH] net: fec: clean up transmit descriptor setup Avoid writing any state until we're certain we can proceed with the transmission: this avoids writing mapping error address values to the descriptors, or setting the skbuff pointer until we have successfully mapped the skb. Acked-by: Fugang Duan Signed-off-by: Russell King Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec_main.c | 33 ++++++++++++----------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 70853a59627a..9c5570a3e32e 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -373,6 +373,7 @@ fec_enet_txq_submit_frag_skb(struct sk_buff *skb, struct net_device *ndev) skb_frag_t *this_frag; unsigned int index; void *bufaddr; + dma_addr_t addr; int i; for (frag = 0; frag < nr_frags; frag++) { @@ -415,15 +416,16 @@ fec_enet_txq_submit_frag_skb(struct sk_buff *skb, struct net_device *ndev) swap_buffer(bufaddr, frag_len); } - bdp->cbd_bufaddr = dma_map_single(&fep->pdev->dev, bufaddr, - frag_len, DMA_TO_DEVICE); - if (dma_mapping_error(&fep->pdev->dev, bdp->cbd_bufaddr)) { + addr = dma_map_single(&fep->pdev->dev, bufaddr, frag_len, + DMA_TO_DEVICE); + if (dma_mapping_error(&fep->pdev->dev, addr)) { dev_kfree_skb_any(skb); if (net_ratelimit()) netdev_err(ndev, "Tx DMA memory map failed\n"); goto dma_mapping_error; } + bdp->cbd_bufaddr = addr; bdp->cbd_datlen = frag_len; bdp->cbd_sc = status; } @@ -450,6 +452,7 @@ static int fec_enet_txq_submit_skb(struct sk_buff *skb, struct net_device *ndev) int nr_frags = skb_shinfo(skb)->nr_frags; struct bufdesc *bdp, *last_bdp; void *bufaddr; + dma_addr_t addr; unsigned short status; unsigned short buflen; unsigned int estatus = 0; @@ -490,12 +493,9 @@ static int fec_enet_txq_submit_skb(struct sk_buff *skb, struct net_device *ndev) swap_buffer(bufaddr, buflen); } - /* Push the data cache so the CPM does not get stale memory - * data. - */ - bdp->cbd_bufaddr = dma_map_single(&fep->pdev->dev, bufaddr, - buflen, DMA_TO_DEVICE); - if (dma_mapping_error(&fep->pdev->dev, bdp->cbd_bufaddr)) { + /* Push the data cache so the CPM does not get stale memory data. */ + addr = dma_map_single(&fep->pdev->dev, bufaddr, buflen, DMA_TO_DEVICE); + if (dma_mapping_error(&fep->pdev->dev, addr)) { dev_kfree_skb_any(skb); if (net_ratelimit()) netdev_err(ndev, "Tx DMA memory map failed\n"); @@ -537,6 +537,7 @@ static int fec_enet_txq_submit_skb(struct sk_buff *skb, struct net_device *ndev) fep->tx_skbuff[index] = skb; bdp->cbd_datlen = buflen; + bdp->cbd_bufaddr = addr; /* Send it on its way. Tell FEC it's ready, interrupt when done, * it's the last BD of the frame, and to put the CRC on the end. @@ -570,12 +571,12 @@ fec_enet_txq_put_data_tso(struct sk_buff *skb, struct net_device *ndev, struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp; unsigned short status; unsigned int estatus = 0; + dma_addr_t addr; status = bdp->cbd_sc; status &= ~BD_ENET_TX_STATS; status |= (BD_ENET_TX_TC | BD_ENET_TX_READY); - bdp->cbd_datlen = size; if (((unsigned long) data) & FEC_ALIGNMENT || id_entry->driver_data & FEC_QUIRK_SWAP_FRAME) { @@ -586,15 +587,17 @@ fec_enet_txq_put_data_tso(struct sk_buff *skb, struct net_device *ndev, swap_buffer(data, size); } - bdp->cbd_bufaddr = dma_map_single(&fep->pdev->dev, data, - size, DMA_TO_DEVICE); - if (dma_mapping_error(&fep->pdev->dev, bdp->cbd_bufaddr)) { + addr = dma_map_single(&fep->pdev->dev, data, size, DMA_TO_DEVICE); + if (dma_mapping_error(&fep->pdev->dev, addr)) { dev_kfree_skb_any(skb); if (net_ratelimit()) netdev_err(ndev, "Tx DMA memory map failed\n"); return NETDEV_TX_BUSY; } + bdp->cbd_datlen = size; + bdp->cbd_bufaddr = addr; + if (fep->bufdesc_ex) { if (skb->ip_summed == CHECKSUM_PARTIAL) estatus |= BD_ENET_TX_PINS | BD_ENET_TX_IINS; @@ -801,7 +804,7 @@ static void fec_enet_bd_init(struct net_device *dev) /* Initialize the BD for every fragment in the page. */ bdp->cbd_sc = 0; - if (bdp->cbd_bufaddr && fep->tx_skbuff[i]) { + if (fep->tx_skbuff[i]) { dev_kfree_skb_any(fep->tx_skbuff[i]); fep->tx_skbuff[i] = NULL; } @@ -1100,6 +1103,7 @@ fec_enet_tx(struct net_device *ndev) index = fec_enet_get_bd_index(fep->tx_bd_base, bdp, fep); skb = fep->tx_skbuff[index]; + fep->tx_skbuff[index] = NULL; if (!IS_TSO_HEADER(fep, bdp->cbd_bufaddr)) dma_unmap_single(&fep->pdev->dev, bdp->cbd_bufaddr, bdp->cbd_datlen, DMA_TO_DEVICE); @@ -1154,7 +1158,6 @@ fec_enet_tx(struct net_device *ndev) /* Free the sk buffer associated with this last transmit */ dev_kfree_skb_any(skb); - fep->tx_skbuff[index] = NULL; fep->dirty_tx = bdp; -- 2.20.1