From patchwork Tue Jan 27 00:50:24 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Hutchings X-Patchwork-Id: 433105 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3E5BE1401DD for ; Tue, 27 Jan 2015 11:50:29 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757163AbbA0Au0 (ORCPT ); Mon, 26 Jan 2015 19:50:26 -0500 Received: from ducie-dc1.codethink.co.uk ([185.25.241.215]:50239 "EHLO ducie-dc1.codethink.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756659AbbA0AuY (ORCPT ); Mon, 26 Jan 2015 19:50:24 -0500 Received: from localhost (localhost [127.0.0.1]) by ducie-dc1.codethink.co.uk (Postfix) with ESMTP id E7D9546036C; Tue, 27 Jan 2015 00:50:22 +0000 (GMT) X-Virus-Scanned: Debian amavisd-new at ducie-dc1.codethink.co.uk Received: from ducie-dc1.codethink.co.uk ([127.0.0.1]) by localhost (ducie-dc1.codethink.co.uk [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id vOcBwMk4PC28; Tue, 27 Jan 2015 00:50:20 +0000 (GMT) Received: from [192.168.25.61] (unknown [192.168.25.61]) by ducie-dc1.codethink.co.uk (Postfix) with ESMTPSA id 5744146062E; Tue, 27 Jan 2015 00:50:19 +0000 (GMT) Message-ID: <1422319824.3524.24.camel@xylophone.i.decadent.org.uk> Subject: [PATCH kernel 4/4] sh_eth: Fix DMA-API usage for RX buffers From: Ben Hutchings To: "David S.Miller" Cc: netdev@vger.kernel.org, linux-kernel@lists.codethink.co.uk, Nobuhiro Iwamatsu , Mitsuhiro Kimura , Hisashi Nakamura , Yoshihiro Kaneko Date: Tue, 27 Jan 2015 00:50:24 +0000 In-Reply-To: <1422319232.3524.14.camel@xylophone.i.decadent.org.uk> References: <1422319232.3524.14.camel@xylophone.i.decadent.org.uk> Organization: Codethink Ltd. X-Mailer: Evolution 3.4.4-3 Mime-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org - Use the return value of dma_map_single(), rather than calling virt_to_page() separately - Check for mapping failue - Call dma_unmap_single() rather than dma_sync_single_for_cpu() Signed-off-by: Ben Hutchings --- drivers/net/ethernet/renesas/sh_eth.c | 34 ++++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 11 deletions(-) diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c index 48610ed..4da8bd2 100644 --- a/drivers/net/ethernet/renesas/sh_eth.c +++ b/drivers/net/ethernet/renesas/sh_eth.c @@ -1123,6 +1123,7 @@ static void sh_eth_ring_format(struct net_device *ndev) int rx_ringsize = sizeof(*rxdesc) * mdp->num_rx_ring; int tx_ringsize = sizeof(*txdesc) * mdp->num_tx_ring; int skbuff_size = mdp->rx_buf_sz + SH_ETH_RX_ALIGN - 1; + dma_addr_t dma_addr; mdp->cur_rx = 0; mdp->cur_tx = 0; @@ -1136,7 +1137,6 @@ static void sh_eth_ring_format(struct net_device *ndev) /* skb */ mdp->rx_skbuff[i] = NULL; skb = netdev_alloc_skb(ndev, skbuff_size); - mdp->rx_skbuff[i] = skb; if (skb == NULL) break; sh_eth_set_receive_align(skb); @@ -1145,9 +1145,15 @@ static void sh_eth_ring_format(struct net_device *ndev) rxdesc = &mdp->rx_ring[i]; /* The size of the buffer is a multiple of 16 bytes. */ rxdesc->buffer_length = ALIGN(mdp->rx_buf_sz, 16); - dma_map_single(&ndev->dev, skb->data, rxdesc->buffer_length, - DMA_FROM_DEVICE); - rxdesc->addr = virt_to_phys(skb->data); + dma_addr = dma_map_single(&ndev->dev, skb->data, + rxdesc->buffer_length, + DMA_FROM_DEVICE); + if (dma_mapping_error(&ndev->dev, dma_addr)) { + kfree_skb(skb); + break; + } + mdp->rx_skbuff[i] = skb; + rxdesc->addr = dma_addr; rxdesc->status = cpu_to_edmac(mdp, RD_RACT | RD_RFP); /* Rx descriptor address set */ @@ -1432,6 +1438,7 @@ static int sh_eth_rx(struct net_device *ndev, u32 intr_status, int *quota) u16 pkt_len = 0; u32 desc_status; int skbuff_size = mdp->rx_buf_sz + SH_ETH_RX_ALIGN - 1; + dma_addr_t dma_addr; boguscnt = min(boguscnt, *quota); limit = boguscnt; @@ -1479,9 +1486,9 @@ static int sh_eth_rx(struct net_device *ndev, u32 intr_status, int *quota) mdp->rx_skbuff[entry] = NULL; if (mdp->cd->rpadir) skb_reserve(skb, NET_IP_ALIGN); - dma_sync_single_for_cpu(&ndev->dev, rxdesc->addr, - ALIGN(mdp->rx_buf_sz, 16), - DMA_FROM_DEVICE); + dma_unmap_single(&ndev->dev, rxdesc->addr, + ALIGN(mdp->rx_buf_sz, 16), + DMA_FROM_DEVICE); skb_put(skb, pkt_len); skb->protocol = eth_type_trans(skb, ndev); netif_receive_skb(skb); @@ -1501,15 +1508,20 @@ static int sh_eth_rx(struct net_device *ndev, u32 intr_status, int *quota) if (mdp->rx_skbuff[entry] == NULL) { skb = netdev_alloc_skb(ndev, skbuff_size); - mdp->rx_skbuff[entry] = skb; if (skb == NULL) break; /* Better luck next round. */ sh_eth_set_receive_align(skb); - dma_map_single(&ndev->dev, skb->data, - rxdesc->buffer_length, DMA_FROM_DEVICE); + dma_addr = dma_map_single(&ndev->dev, skb->data, + rxdesc->buffer_length, + DMA_FROM_DEVICE); + if (dma_mapping_error(&ndev->dev, dma_addr)) { + kfree_skb(skb); + break; + } + mdp->rx_skbuff[entry] = skb; skb_checksum_none_assert(skb); - rxdesc->addr = virt_to_phys(skb->data); + rxdesc->addr = dma_addr; } if (entry >= mdp->num_rx_ring - 1) rxdesc->status |=