From cce027ca23fb3fd437c96587832a530d83dab48f Mon Sep 17 00:00:00 2001 From: =?utf8?q?fran=C3=A7ois=20romieu?= Date: Sat, 18 May 2013 01:24:46 +0000 Subject: [PATCH] r8169: fix offloaded tx checksum for small packets. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 8168evl offloaded checksums are wrong since commit f14e1cb1c68ddb91db6d246fd584142d7097b2e1 ("r8169: fix 8168evl frame padding.") pads small packets to 60 bytes (without ethernet checksum). Typical symptoms appear as UDP checksums which are wrong by the count of added bytes. It isn't worth compensating. Let the driver checksum. Due to the skb length changes, TSO code is moved before the Tx descriptor gets written. Signed-off-by: Francois Romieu Tested-by: Holger Hoffstätte Signed-off-by: David S. Miller --- drivers/net/ethernet/realtek/r8169.c | 41 ++++++++++++++++++---------- 1 file changed, 27 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c index 79c520b64fddd..393f961a013ce 100644 --- a/drivers/net/ethernet/realtek/r8169.c +++ b/drivers/net/ethernet/realtek/r8169.c @@ -5856,7 +5856,20 @@ err_out: return -EIO; } -static inline void rtl8169_tso_csum(struct rtl8169_private *tp, +static bool rtl_skb_pad(struct sk_buff *skb) +{ + if (skb_padto(skb, ETH_ZLEN)) + return false; + skb_put(skb, ETH_ZLEN - skb->len); + return true; +} + +static bool rtl_test_hw_pad_bug(struct rtl8169_private *tp, struct sk_buff *skb) +{ + return skb->len < ETH_ZLEN && tp->mac_version == RTL_GIGA_MAC_VER_34; +} + +static inline bool rtl8169_tso_csum(struct rtl8169_private *tp, struct sk_buff *skb, u32 *opts) { const struct rtl_tx_desc_info *info = tx_desc_info + tp->txd_version; @@ -5869,13 +5882,20 @@ static inline void rtl8169_tso_csum(struct rtl8169_private *tp, } else if (skb->ip_summed == CHECKSUM_PARTIAL) { const struct iphdr *ip = ip_hdr(skb); + if (unlikely(rtl_test_hw_pad_bug(tp, skb))) + return skb_checksum_help(skb) == 0 && rtl_skb_pad(skb); + if (ip->protocol == IPPROTO_TCP) opts[offset] |= info->checksum.tcp; else if (ip->protocol == IPPROTO_UDP) opts[offset] |= info->checksum.udp; else WARN_ON_ONCE(1); + } else { + if (unlikely(rtl_test_hw_pad_bug(tp, skb))) + return rtl_skb_pad(skb); } + return true; } static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, @@ -5896,17 +5916,15 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, goto err_stop_0; } - /* 8168evl does not automatically pad to minimum length. */ - if (unlikely(tp->mac_version == RTL_GIGA_MAC_VER_34 && - skb->len < ETH_ZLEN)) { - if (skb_padto(skb, ETH_ZLEN)) - goto err_update_stats; - skb_put(skb, ETH_ZLEN - skb->len); - } - if (unlikely(le32_to_cpu(txd->opts1) & DescOwn)) goto err_stop_0; + opts[1] = cpu_to_le32(rtl8169_tx_vlan_tag(skb)); + opts[0] = DescOwn; + + if (!rtl8169_tso_csum(tp, skb, opts)) + goto err_update_stats; + len = skb_headlen(skb); mapping = dma_map_single(d, skb->data, len, DMA_TO_DEVICE); if (unlikely(dma_mapping_error(d, mapping))) { @@ -5918,11 +5936,6 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb, tp->tx_skb[entry].len = len; txd->addr = cpu_to_le64(mapping); - opts[1] = cpu_to_le32(rtl8169_tx_vlan_tag(skb)); - opts[0] = DescOwn; - - rtl8169_tso_csum(tp, skb, opts); - frags = rtl8169_xmit_frags(tp, skb, opts); if (frags < 0) goto err_dma_1; -- 2.39.5