From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759956Ab3GaN0a (ORCPT ); Wed, 31 Jul 2013 09:26:30 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:47130 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759874Ab3GaN0J (ORCPT ); Wed, 31 Jul 2013 09:26:09 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Neil Horman" , "Jay Cliburn" , "Ben Hutchings" , "David S. Miller" , "Chris Snook" Date: Wed, 31 Jul 2013 15:23:09 +0200 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [21/84] atl1e: unmap partially mapped skb on dma error and free skb In-Reply-To: X-SA-Exim-Connect-IP: 151.216.67.181 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Neil Horman [ Upstream commit 584ec4355355ffac43571b02a314d43eb2f7fcbf ] Ben Hutchings pointed out that my recent update to atl1e in commit 352900b583b2852152a1e05ea0e8b579292e731e ("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" Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- 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 ec08ccd..87851f0 100644 --- a/drivers/net/ethernet/atheros/atl1e/atl1e_main.c +++ b/drivers/net/ethernet/atheros/atl1e/atl1e_main.c @@ -1698,6 +1698,7 @@ 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; @@ -1741,6 +1742,15 @@ 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; @@ -1783,6 +1793,16 @@ 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; @@ -1873,8 +1893,10 @@ 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);