Merge branch 'r8169_tso_ipv6'

Hayes Wang says:

====================
r8169: support IPv6

The RTL8168C and the later chips support the hardware checksum
for IPv6. Adjust some code and add the relative code.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 181 insertions, 39 deletions

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index be425ad5e824..51c78ce27b37 100644
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -27,6 +27,8 @@
 #include <linux/firmware.h>
 #include <linux/pci-aspm.h>
 #include <linux/prefetch.h>
+#include <linux/ipv6.h>
+#include <net/ip6_checksum.h>
 
 #include <asm/io.h>
 #include <asm/irq.h>
@@ -626,39 +628,22 @@ enum rtl_tx_desc_bit_0 {
 
 /* 8102e, 8168c and beyond. */
 enum rtl_tx_desc_bit_1 {
+        /* First doubleword. */
+        TD1_GTSENV4     = (1 << 26),            /* Giant Send for IPv4 */
+        TD1_GTSENV6     = (1 << 25),            /* Giant Send for IPv6 */
+#define GTTCPHO_SHIFT                   18
+#define GTTCPHO_MAX                     0x7fU
+
         /* Second doubleword. */
+#define TCPHO_SHIFT                     18
+#define TCPHO_MAX                       0x3ffU
 #define TD1_MSS_SHIFT                   18      /* MSS position (11 bits) */
-        TD1_IP_CS       = (1 << 29),            /* Calculate IP checksum */
+        TD1_IPv6_CS     = (1 << 28),            /* Calculate IPv6 checksum */
+        TD1_IPv4_CS     = (1 << 29),            /* Calculate IPv4 checksum */
         TD1_TCP_CS      = (1 << 30),            /* Calculate TCP/IP checksum */
         TD1_UDP_CS      = (1 << 31),            /* Calculate UDP/IP checksum */
 };
 
-static const struct rtl_tx_desc_info {
-        struct {
-                u32 udp;
-                u32 tcp;
-        } checksum;
-        u16 mss_shift;
-        u16 opts_offset;
-} tx_desc_info [] = {
-        [RTL_TD_0] = {
-                .checksum = {
-                        .udp    = TD0_IP_CS | TD0_UDP_CS,
-                        .tcp    = TD0_IP_CS | TD0_TCP_CS
-                },
-                .mss_shift      = TD0_MSS_SHIFT,
-                .opts_offset    = 0
-        },
-        [RTL_TD_1] = {
-                .checksum = {
-                        .udp    = TD1_IP_CS | TD1_UDP_CS,
-                        .tcp    = TD1_IP_CS | TD1_TCP_CS
-                },
-                .mss_shift      = TD1_MSS_SHIFT,
-                .opts_offset    = 1
-        }
-};
-
 enum rtl_rx_desc_bit {
         /* Rx private */
         PID1            = (1 << 18), /* Protocol ID bit 1/2 */
@@ -782,6 +767,7 @@ struct rtl8169_private {
         unsigned int (*phy_reset_pending)(struct rtl8169_private *tp);
         unsigned int (*link_ok)(void __iomem *);
         int (*do_ioctl)(struct rtl8169_private *tp, struct mii_ioctl_data *data, int cmd);
+        bool (*tso_csum)(struct rtl8169_private *, struct sk_buff *, u32 *);
 
         struct {
                 DECLARE_BITMAP(flags, RTL_FLAG_MAX);
@@ -5941,32 +5927,179 @@ 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)
+static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb,
+                                      struct net_device *dev);
+/* r8169_csum_workaround()
+ * The hw limites the value the transport offset. When the offset is out of the
+ * range, calculate the checksum by sw.
+ */
+static void r8169_csum_workaround(struct rtl8169_private *tp,
+                                  struct sk_buff *skb)
+{
+        if (skb_shinfo(skb)->gso_size) {
+                netdev_features_t features = tp->dev->features;
+                struct sk_buff *segs, *nskb;
+
+                features &= ~(NETIF_F_SG | NETIF_F_IPV6_CSUM | NETIF_F_TSO6);
+                segs = skb_gso_segment(skb, features);
+                if (IS_ERR(segs) || !segs)
+                        goto drop;
+
+                do {
+                        nskb = segs;
+                        segs = segs->next;
+                        nskb->next = NULL;
+                        rtl8169_start_xmit(nskb, tp->dev);
+                } while (segs);
+
+                dev_kfree_skb(skb);
+        } else if (skb->ip_summed == CHECKSUM_PARTIAL) {
+                if (skb_checksum_help(skb) < 0)
+                        goto drop;
+
+                rtl8169_start_xmit(skb, tp->dev);
+        } else {
+                struct net_device_stats *stats;
+
+drop:
+                stats = &tp->dev->stats;
+                stats->tx_dropped++;
+                dev_kfree_skb(skb);
+        }
+}
+
+/* msdn_giant_send_check()
+ * According to the document of microsoft, the TCP Pseudo Header excludes the
+ * packet length for IPv6 TCP large packets.
+ */
+static int msdn_giant_send_check(struct sk_buff *skb)
+{
+        const struct ipv6hdr *ipv6h;
+        struct tcphdr *th;
+        int ret;
+
+        ret = skb_cow_head(skb, 0);
+        if (ret)
+                return ret;
+
+        ipv6h = ipv6_hdr(skb);
+        th = tcp_hdr(skb);
+
+        th->check = 0;
+        th->check = ~tcp_v6_check(0, &ipv6h->saddr, &ipv6h->daddr, 0);
+
+        return ret;
+}
+
+static inline __be16 get_protocol(struct sk_buff *skb)
+{
+        __be16 protocol;
+
+        if (skb->protocol == htons(ETH_P_8021Q))
+                protocol = vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
+        else
+                protocol = skb->protocol;
+
+        return protocol;
+}
+
+static bool rtl8169_tso_csum_v1(struct rtl8169_private *tp,
+                                struct sk_buff *skb, u32 *opts)
 {
-        const struct rtl_tx_desc_info *info = tx_desc_info + tp->txd_version;
         u32 mss = skb_shinfo(skb)->gso_size;
-        int offset = info->opts_offset;
 
         if (mss) {
                 opts[0] |= TD_LSO;
-                opts[offset] |= min(mss, TD_MSS_MAX) << info->mss_shift;
+                opts[0] |= min(mss, TD_MSS_MAX) << TD0_MSS_SHIFT;
         } else if (skb->ip_summed == CHECKSUM_PARTIAL) {
                 const struct iphdr *ip = ip_hdr(skb);
 
+                if (ip->protocol == IPPROTO_TCP)
+                        opts[0] |= TD0_IP_CS | TD0_TCP_CS;
+                else if (ip->protocol == IPPROTO_UDP)
+                        opts[0] |= TD0_IP_CS | TD0_UDP_CS;
+                else
+                        WARN_ON_ONCE(1);
+        }
+
+        return true;
+}
+
+static bool rtl8169_tso_csum_v2(struct rtl8169_private *tp,
+                                struct sk_buff *skb, u32 *opts)
+{
+        u32 transport_offset = (u32)skb_transport_offset(skb);
+        u32 mss = skb_shinfo(skb)->gso_size;
+
+        if (mss) {
+                if (transport_offset > GTTCPHO_MAX) {
+                        netif_warn(tp, tx_err, tp->dev,
+                                   "Invalid transport offset 0x%x for TSO\n",
+                                   transport_offset);
+                        return false;
+                }
+
+                switch (get_protocol(skb)) {
+                case htons(ETH_P_IP):
+                        opts[0] |= TD1_GTSENV4;
+                        break;
+
+                case htons(ETH_P_IPV6):
+                        if (msdn_giant_send_check(skb))
+                                return false;
+
+                        opts[0] |= TD1_GTSENV6;
+                        break;
+
+                default:
+                        WARN_ON_ONCE(1);
+                        break;
+                }
+
+                opts[0] |= transport_offset << GTTCPHO_SHIFT;
+                opts[1] |= min(mss, TD_MSS_MAX) << TD1_MSS_SHIFT;
+        } else if (skb->ip_summed == CHECKSUM_PARTIAL) {
+                u8 ip_protocol;
+
                 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;
+                if (transport_offset > TCPHO_MAX) {
+                        netif_warn(tp, tx_err, tp->dev,
+                                   "Invalid transport offset 0x%x\n",
+                                   transport_offset);
+                        return false;
+                }
+
+                switch (get_protocol(skb)) {
+                case htons(ETH_P_IP):
+                        opts[1] |= TD1_IPv4_CS;
+                        ip_protocol = ip_hdr(skb)->protocol;
+                        break;
+
+                case htons(ETH_P_IPV6):
+                        opts[1] |= TD1_IPv6_CS;
+                        ip_protocol = ipv6_hdr(skb)->nexthdr;
+                        break;
+
+                default:
+                        ip_protocol = IPPROTO_RAW;
+                        break;
+                }
+
+                if (ip_protocol == IPPROTO_TCP)
+                        opts[1] |= TD1_TCP_CS;
+                else if (ip_protocol == IPPROTO_UDP)
+                        opts[1] |= TD1_UDP_CS;
                 else
                         WARN_ON_ONCE(1);
+
+                opts[1] |= transport_offset << TCPHO_SHIFT;
         } else {
                 if (unlikely(rtl_test_hw_pad_bug(tp, skb)))
                         return rtl_skb_pad(skb);
         }
+
         return true;
 }
 
@@ -5994,8 +6127,10 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb,
         opts[1] = cpu_to_le32(rtl8169_tx_vlan_tag(skb));
         opts[0] = DescOwn;
 
-        if (!rtl8169_tso_csum(tp, skb, opts))
-                goto err_update_stats;
+        if (!tp->tso_csum(tp, skb, opts)) {
+                r8169_csum_workaround(tp, skb);
+                return NETDEV_TX_OK;
+        }
 
         len = skb_headlen(skb);
         mapping = dma_map_single(d, skb->data, len, DMA_TO_DEVICE);
@@ -6060,7 +6195,6 @@ err_dma_1:
         rtl8169_unmap_tx_skb(d, tp->tx_skb + entry, txd);
 err_dma_0:
         dev_kfree_skb_any(skb);
-err_update_stats:
         dev->stats.tx_dropped++;
         return NETDEV_TX_OK;
 
@@ -7145,6 +7279,14 @@ rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
                 /* 8110SCd requires hardware Rx VLAN - disallow toggling */
                 dev->hw_features &= ~NETIF_F_HW_VLAN_CTAG_RX;
 
+        if (tp->txd_version == RTL_TD_0)
+                tp->tso_csum = rtl8169_tso_csum_v1;
+        else if (tp->txd_version == RTL_TD_1) {
+                tp->tso_csum = rtl8169_tso_csum_v2;
+                dev->hw_features |= NETIF_F_IPV6_CSUM | NETIF_F_TSO6;
+        } else
+                WARN_ON_ONCE(1);
+
         dev->hw_features |= NETIF_F_RXALL;
         dev->hw_features |= NETIF_F_RXFCS;