From patchwork Tue Jul 16 14:49:41 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Neil Horman X-Patchwork-Id: 259422 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 749CB2C0126 for ; Wed, 17 Jul 2013 00:50:21 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932955Ab3GPOuO (ORCPT ); Tue, 16 Jul 2013 10:50:14 -0400 Received: from charlotte.tuxdriver.com ([70.61.120.58]:33128 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932536Ab3GPOuL (ORCPT ); Tue, 16 Jul 2013 10:50:11 -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 1Uz6Zc-0003F6-7s; Tue, 16 Jul 2013 10:50:06 -0400 From: Neil Horman To: netdev@vger.kernel.org Cc: Neil Horman , Ben Hutchings , Jay Cliburn , Chris Snook , "David S. Miller" Subject: [net PATCH] atl1e: unmap partially mapped skb on dma error and free skb Date: Tue, 16 Jul 2013 10:49:41 -0400 Message-Id: <1373986181-15797-1-git-send-email-nhorman@tuxdriver.com> X-Mailer: git-send-email 1.8.1.4 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 Ben Hutchings pointed out that my recent update to atl1e: commit 352900b583b2852152a1e05ea0e8b579292e731e Author: Neil Horman Date: Fri Jul 12 10:58:48 2013 -0400 atl1e: fix dma mapping warnings Was missing a bit of code. Specifically it reset the hardware tx ring to its origional state when we hit a dma error, but didn't unmap any exiting mappings from the operation. This patch fixes that up. It also remembers to free the skb in the event that an error occurs, so we don't leak. Untested, as I don't have hardware. I think its pretty straightforward, but please review closely. Signed-off-by: Neil Horman CC: Ben Hutchings CC: Jay Cliburn CC: Chris Snook CC: "David S. Miller" --- drivers/net/ethernet/atheros/atl1e/atl1e_main.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c index 6d1a62a..1966444 100644 --- a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c +++ b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c @@ -1678,6 +1678,7 @@ static int atl1e_tx_map(struct atl1e_adapter *adapter, u16 f; int segment; int ring_start = adapter->tx_ring.next_to_use; + int ring_end; nr_frags = skb_shinfo(skb)->nr_frags; segment = (tpd->word3 >> TPD_SEGMENT_EN_SHIFT) & TPD_SEGMENT_EN_MASK; @@ -1721,6 +1722,15 @@ static int atl1e_tx_map(struct atl1e_adapter *adapter, map_len, PCI_DMA_TODEVICE); if (dma_mapping_error(&adapter->pdev->dev, tx_buffer->dma)) { + /* We need to unwind the mappings we've done */ + ring_end = adapter->tx_ring.next_to_use; + adapter->tx_ring.next_to_use = ring_start; + while (adapter->tx_ring.next_to_use != ring_end) { + tpd = atl1e_get_tpd(adapter); + tx_buffer = atl1e_get_tx_buffer(adapter, tpd); + pci_unmap_single(adapter->pdev, tx_buffer->dma, + tx_buffer->length, PCI_DMA_TODEVICE); + } /* Reset the tx rings next pointer */ adapter->tx_ring.next_to_use = ring_start; return -ENOSPC; @@ -1763,6 +1773,16 @@ static int atl1e_tx_map(struct atl1e_adapter *adapter, DMA_TO_DEVICE); if (dma_mapping_error(&adapter->pdev->dev, tx_buffer->dma)) { + /* We need to unwind the mappings we've done */ + ring_end = adapter->tx_ring.next_to_use; + adapter->tx_ring.next_to_use = ring_start; + while (adapter->tx_ring.next_to_use != ring_end) { + tpd = atl1e_get_tpd(adapter); + tx_buffer = atl1e_get_tx_buffer(adapter, tpd); + dma_unmap_page(&adapter->pdev->dev, tx_buffer->dma, + tx_buffer->length, DMA_TO_DEVICE); + } + /* Reset the ring next to use pointer */ adapter->tx_ring.next_to_use = ring_start; return -ENOSPC; @@ -1853,8 +1873,10 @@ static netdev_tx_t atl1e_xmit_frame(struct sk_buff *skb, return NETDEV_TX_OK; } - if (atl1e_tx_map(adapter, skb, tpd)) + if (atl1e_tx_map(adapter, skb, tpd)) { + dev_kfree_skb_any(skb); goto out; + } atl1e_tx_queue(adapter, tpd_req, tpd);