From patchwork Tue Sep 16 14:32:17 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Neil Horman X-Patchwork-Id: 390082 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 E0AE0140090 for ; Wed, 17 Sep 2014 00:32:58 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754489AbaIPOcn (ORCPT ); Tue, 16 Sep 2014 10:32:43 -0400 Received: from charlotte.tuxdriver.com ([70.61.120.58]:33778 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754228AbaIPOcl (ORCPT ); Tue, 16 Sep 2014 10:32:41 -0400 Received: from hmsreliant.think-freely.org ([2001:470:8:a08:7aac:c0ff:fec2:933b] helo=localhost) by smtp.tuxdriver.com with esmtpsa (TLSv1:AES128-SHA:128) (Exim 4.63) (envelope-from ) id 1XTto0-0000oQ-O6; Tue, 16 Sep 2014 10:32:39 -0400 From: Neil Horman To: netdev@vger.kernel.org Cc: Meelis Roos , linux-kernel@vger.kernel.org, Neil Horman Subject: [RFC PATCH] 3c59x: Add dma error checking and recovery Date: Tue, 16 Sep 2014 10:32:17 -0400 Message-Id: <1410877937-27487-1-git-send-email-nhorman@tuxdriver.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <20140916101704.GA3792@hmsreliant.think-freely.org> References: <20140916101704.GA3792@hmsreliant.think-freely.org> X-Spam-Score: -2.9 (--) X-Spam-Status: No Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Noted that 3c59x has no checks on transmit for failed DMA mappings, and no ability to unmap fragments when a single map fails in the middle of a transmit. This patch provides error checking to ensure that dma mappings work properly, and unrolls an skb mapping if a fragmented skb transmission has a mapping failure to prevent leaks. Please test this patch out. It may fix the problem your experiencing, and, if you enable dynamic debug in the driver, it will certainly confirm that is the problem you are experiencing. Signed-off-by: Neil Horman --- drivers/net/ethernet/3com/3c59x.c | 50 ++++++++++++++++++++++++++++++++------- 1 file changed, 41 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/3com/3c59x.c b/drivers/net/ethernet/3com/3c59x.c index 3fe45c7..5621dab 100644 --- a/drivers/net/ethernet/3com/3c59x.c +++ b/drivers/net/ethernet/3com/3c59x.c @@ -2129,6 +2129,7 @@ boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev) int entry = vp->cur_tx % TX_RING_SIZE; struct boom_tx_desc *prev_entry = &vp->tx_ring[(vp->cur_tx-1) % TX_RING_SIZE]; unsigned long flags; + dma_addr_t dma_addr; if (vortex_debug > 6) { pr_debug("boomerang_start_xmit()\n"); @@ -2163,24 +2164,48 @@ boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev) vp->tx_ring[entry].status = cpu_to_le32(skb->len | TxIntrUploaded | AddTCPChksum | AddUDPChksum); if (!skb_shinfo(skb)->nr_frags) { - vp->tx_ring[entry].frag[0].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, - skb->len, PCI_DMA_TODEVICE)); + dma_addr = pci_map_single(VORTEX_PCI(vp), skb->data, skb->len, + PCI_DMA_TODEVICE); + if (dma_mapping_error(&VORTEX_PCI(vp)->dev, dma_addr)) + goto out_dma_err; + + vp->tx_ring[entry].frag[0].addr = cpu_to_le32(dma_addr); vp->tx_ring[entry].frag[0].length = cpu_to_le32(skb->len | LAST_FRAG); } else { int i; - vp->tx_ring[entry].frag[0].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, - skb_headlen(skb), PCI_DMA_TODEVICE)); + dma_addr = pci_map_single(VORTEX_PCI(vp), skb->data, + skb_headlen(skb), PCI_DMA_TODEVICE); + if (dma_mapping_error(&VORTEX_PCI(vp)->dev, dma_addr)) + goto out_dma_err; + + vp->tx_ring[entry].frag[0].addr = cpu_to_le32(dma_addr); vp->tx_ring[entry].frag[0].length = cpu_to_le32(skb_headlen(skb)); for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + dma_addr = skb_frag_dma_map(&VORTEX_PCI(vp)->dev, frag, + frag->page_offset, + frag->size, + DMA_TO_DEVICE); + if (dma_mapping_error(&VORTEX_PCI(vp)->dev, dma_addr)) { + for(i = i-1; i >= 0; i--) + dma_unmap_page(&VORTEX_PCI(vp)->dev, + le32_to_cpu(vp->tx_ring[entry].frag[i+1].addr), + le32_to_cpu(vp->tx_ring[entry].frag[i+1].length), + DMA_TO_DEVICE); + + pci_unmap_single(VORTEX_PCI(vp), + le32_to_cpu(vp->tx_ring[entry].frag[0].addr), + le32_to_cpu(vp->tx_ring[entry].frag[0].length), + PCI_DMA_TODEVICE); + + goto out_dma_err; + } + vp->tx_ring[entry].frag[i+1].addr = - cpu_to_le32(skb_frag_dma_map( - &VORTEX_PCI(vp)->dev, - frag, - frag->page_offset, frag->size, DMA_TO_DEVICE)); + cpu_to_le32(dma_addr); if (i == skb_shinfo(skb)->nr_frags-1) vp->tx_ring[entry].frag[i+1].length = cpu_to_le32(skb_frag_size(frag)|LAST_FRAG); @@ -2189,7 +2214,10 @@ boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev) } } #else - vp->tx_ring[entry].addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, skb->len, PCI_DMA_TODEVICE)); + dma_addr = cpu_to_le32(pci_map_single(VORTEX_PCI(vp), skb->data, skb->len, PCI_DMA_TODEVICE)); + if (dma_mapping_error(&VORTEX_PCI(vp)->dev, dma_addr)) + goto out_dma_err; + vp->tx_ring[entry].addr = cpu_to_le32(dma_addr); vp->tx_ring[entry].length = cpu_to_le32(skb->len | LAST_FRAG); vp->tx_ring[entry].status = cpu_to_le32(skb->len | TxIntrUploaded); #endif @@ -2217,7 +2245,11 @@ boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev) skb_tx_timestamp(skb); iowrite16(DownUnstall, ioaddr + EL3_CMD); spin_unlock_irqrestore(&vp->lock, flags); +out: return NETDEV_TX_OK; +out_dma_err: + dev_err(&VORTEX_PCI(vp)->dev, "Error mapping dma buffer\n"); + goto out; } /* The interrupt handler does all of the Rx thread work and cleans up