[net-2.6 PATCH 4/4] ixgbe: fix unmap length bug
From: Jeff Kirsher <hidden>
Date: 2009-06-30 21:45:15
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Jesse Brandeburg <redacted> This patch addresses three WARN_ON statements from DMA-API debug code ixgbe is mapping more than it unmaps, reduce the length of the map call and remove the "used once" local variable. found by Joerg Roedel [off-list ref] in 2.6.30, so is a candidate for -stable. in addition, fix missing ->dma = 0 after unmap to prevent double free with pci_unmap_single and lastly, don't unmap (half) pages that aren't mapped. Signed-off-by: Jesse Brandeburg <redacted> CC: Joerg Roedel <redacted> Signed-off-by: Jeff Kirsher <redacted> --- drivers/net/ixgbe/ixgbe_main.c | 17 +++++++++++------ 1 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index fce2ef4..5588ef4 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c@@ -563,7 +563,6 @@ static void ixgbe_alloc_rx_buffers(struct ixgbe_adapter *adapter, union ixgbe_adv_rx_desc *rx_desc; struct ixgbe_rx_buffer *bi; unsigned int i; - unsigned int bufsz = rx_ring->rx_buf_len + NET_IP_ALIGN; i = rx_ring->next_to_use; bi = &rx_ring->rx_buffer_info[i];
@@ -593,7 +592,9 @@ static void ixgbe_alloc_rx_buffers(struct ixgbe_adapter *adapter, if (!bi->skb) { struct sk_buff *skb; - skb = netdev_alloc_skb(adapter->netdev, bufsz); + skb = netdev_alloc_skb(adapter->netdev, + (rx_ring->rx_buf_len + + NET_IP_ALIGN)); if (!skb) { adapter->alloc_rx_buff_failed++;
@@ -608,7 +609,8 @@ static void ixgbe_alloc_rx_buffers(struct ixgbe_adapter *adapter, skb_reserve(skb, NET_IP_ALIGN); bi->skb = skb; - bi->dma = pci_map_single(pdev, skb->data, bufsz, + bi->dma = pci_map_single(pdev, skb->data, + rx_ring->rx_buf_len, PCI_DMA_FROMDEVICE); } /* Refresh the desc even if buffer_addrs didn't change because
@@ -732,6 +734,7 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, pci_unmap_single(pdev, rx_buffer_info->dma, rx_ring->rx_buf_len, PCI_DMA_FROMDEVICE); + rx_buffer_info->dma = 0; skb_put(skb, len); }
@@ -2815,9 +2818,11 @@ static void ixgbe_clean_rx_ring(struct ixgbe_adapter *adapter, } if (!rx_buffer_info->page) continue; - pci_unmap_page(pdev, rx_buffer_info->page_dma, PAGE_SIZE / 2, - PCI_DMA_FROMDEVICE); - rx_buffer_info->page_dma = 0; + if (rx_buffer_info->page_dma) { + pci_unmap_page(pdev, rx_buffer_info->page_dma, + PAGE_SIZE / 2, PCI_DMA_FROMDEVICE); + rx_buffer_info->page_dma = 0; + } put_page(rx_buffer_info->page); rx_buffer_info->page = NULL; rx_buffer_info->page_offset = 0;