net: Generalize ndo_gso_check to ndo_features_check

GSO isn't the only offload feature with restrictions that
potentially can't be expressed with the current features mechanism.
Checksum is another although it's a general issue that could in
theory apply to anything. Even if it may be possible to
implement these restrictions in other ways, it can result in
duplicate code or inefficient per-packet behavior.

This generalizes ndo_gso_check so that drivers can remove any
features that don't make sense for a given packet, similar to
netif_skb_features(). It also converts existing driver
restrictions to the new format, completing the work that was
done to support tunnel protocols since the issues apply to
checksums as well.

By actually removing features from the set that are used to do
offloading, it solves another problem with the existing
interface. In these cases, GSO would run with the original set
of features and not do anything because it appears that
segmentation is not required.

CC: Tom Herbert <therbert@google.com>
CC: Joe Stringer <joestringer@nicira.com>
CC: Eric Dumazet <edumazet@google.com>
CC: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Acked-by:  Tom Herbert <therbert@google.com>
Fixes: 04ffcb255f22 ("net: Add ndo_gso_check")
Tested-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
index 9f5e38769a294a3d66d9562e12e2e0116bac925e..72eef9fc883e8983d7544abd685fbb36da19951d 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
@@ -12553,9 +12553,11 @@ static int bnx2x_get_phys_port_id(struct net_device *netdev,
        return 0;
 }
 
-static bool bnx2x_gso_check(struct sk_buff *skb, struct net_device *dev)
+static netdev_features_t bnx2x_features_check(struct sk_buff *skb,
+                                             struct net_device *dev,
+                                             netdev_features_t features)
 {
-       return vxlan_gso_check(skb);
+       return vxlan_features_check(skb, features);
 }
 
 static const struct net_device_ops bnx2x_netdev_ops = {
@@ -12589,7 +12591,7 @@ static const struct net_device_ops bnx2x_netdev_ops = {
 #endif
        .ndo_get_phys_port_id   = bnx2x_get_phys_port_id,
        .ndo_set_vf_link_state  = bnx2x_set_vf_link_state,
-       .ndo_gso_check          = bnx2x_gso_check,
+       .ndo_features_check     = bnx2x_features_check,
 };
 
 static int bnx2x_set_coherency_mask(struct bnx2x *bp)

diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 196073110e320b1bb05e8b38bf9a5e1c66b5e929..41a0a5498da74c7b9b1129b68c9173c1b15470a4 100644 (file)
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -4459,9 +4459,11 @@ done:
        adapter->vxlan_port_count--;
 }
 
-static bool be_gso_check(struct sk_buff *skb, struct net_device *dev)
+static netdev_features_t be_features_check(struct sk_buff *skb,
+                                          struct net_device *dev,
+                                          netdev_features_t features)
 {
-       return vxlan_gso_check(skb);
+       return vxlan_features_check(skb, features);
 }
 #endif
 
@@ -4492,7 +4494,7 @@ static const struct net_device_ops be_netdev_ops = {
 #ifdef CONFIG_BE2NET_VXLAN
        .ndo_add_vxlan_port     = be_add_vxlan_port,
        .ndo_del_vxlan_port     = be_del_vxlan_port,
-       .ndo_gso_check          = be_gso_check,
+       .ndo_features_check     = be_features_check,
 #endif
 };
 

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 190cbd931f6bc8527654d14d042dc85799883a81..d0d6dc1b8e46e8173cbd61f5c2e84d4292301bc4 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2365,9 +2365,11 @@ static void mlx4_en_del_vxlan_port(struct  net_device *dev,
        queue_work(priv->mdev->workqueue, &priv->vxlan_del_task);
 }
 
-static bool mlx4_en_gso_check(struct sk_buff *skb, struct net_device *dev)
+static netdev_features_t mlx4_en_features_check(struct sk_buff *skb,
+                                               struct net_device *dev,
+                                               netdev_features_t features)
 {
-       return vxlan_gso_check(skb);
+       return vxlan_features_check(skb, features);
 }
 #endif
 
@@ -2400,7 +2402,7 @@ static const struct net_device_ops mlx4_netdev_ops = {
 #ifdef CONFIG_MLX4_EN_VXLAN
        .ndo_add_vxlan_port     = mlx4_en_add_vxlan_port,
        .ndo_del_vxlan_port     = mlx4_en_del_vxlan_port,
-       .ndo_gso_check          = mlx4_en_gso_check,
+       .ndo_features_check     = mlx4_en_features_check,
 #endif
 };
 
@@ -2434,7 +2436,7 @@ static const struct net_device_ops mlx4_netdev_ops_master = {
 #ifdef CONFIG_MLX4_EN_VXLAN
        .ndo_add_vxlan_port     = mlx4_en_add_vxlan_port,
        .ndo_del_vxlan_port     = mlx4_en_del_vxlan_port,
-       .ndo_gso_check          = mlx4_en_gso_check,
+       .ndo_features_check     = mlx4_en_features_check,
 #endif
 };
 

diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
index 1aa25b13ace1d2ccce0d5cf10fb07fb3a3158038..9929b97cfb3629d1afb04809f8faefd7302347b8 100644 (file)
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
@@ -505,9 +505,11 @@ static void qlcnic_del_vxlan_port(struct net_device *netdev,
        adapter->flags |= QLCNIC_DEL_VXLAN_PORT;
 }
 
-static bool qlcnic_gso_check(struct sk_buff *skb, struct net_device *dev)
+static netdev_features_t qlcnic_features_check(struct sk_buff *skb,
+                                              struct net_device *dev,
+                                              netdev_features_t features)
 {
-       return vxlan_gso_check(skb);
+       return vxlan_features_check(skb, features);
 }
 #endif
 
@@ -532,7 +534,7 @@ static const struct net_device_ops qlcnic_netdev_ops = {
 #ifdef CONFIG_QLCNIC_VXLAN
        .ndo_add_vxlan_port     = qlcnic_add_vxlan_port,
        .ndo_del_vxlan_port     = qlcnic_del_vxlan_port,
-       .ndo_gso_check          = qlcnic_gso_check,
+       .ndo_features_check     = qlcnic_features_check,
 #endif
 #ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller = qlcnic_poll_controller,

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index c31f74d76ebd3c595160a4b3b513594423f43240..679e6e90aa4c2b1a2e9ea9c3fde52e12ea389b91 100644 (file)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1012,12 +1012,15 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
  *     Callback to use for xmit over the accelerated station. This
  *     is used in place of ndo_start_xmit on accelerated net
  *     devices.
- * bool        (*ndo_gso_check) (struct sk_buff *skb,
- *                       struct net_device *dev);
+ * netdev_features_t (*ndo_features_check) (struct sk_buff *skb,
+ *                                         struct net_device *dev
+ *                                         netdev_features_t features);
  *     Called by core transmit path to determine if device is capable of
- *     performing GSO on a packet. The device returns true if it is
- *     able to GSO the packet, false otherwise. If the return value is
- *     false the stack will do software GSO.
+ *     performing offload operations on a given packet. This is to give
+ *     the device an opportunity to implement any restrictions that cannot
+ *     be otherwise expressed by feature flags. The check is called with
+ *     the set of features that the stack has calculated and it returns
+ *     those the driver believes to be appropriate.
  *
  * int (*ndo_switch_parent_id_get)(struct net_device *dev,
  *                                struct netdev_phys_item_id *psid);
@@ -1178,8 +1181,9 @@ struct net_device_ops {
                                                        struct net_device *dev,
                                                        void *priv);
        int                     (*ndo_get_lock_subclass)(struct net_device *dev);
-       bool                    (*ndo_gso_check) (struct sk_buff *skb,
-                                                 struct net_device *dev);
+       netdev_features_t       (*ndo_features_check) (struct sk_buff *skb,
+                                                      struct net_device *dev,
+                                                      netdev_features_t features);
 #ifdef CONFIG_NET_SWITCHDEV
        int                     (*ndo_switch_parent_id_get)(struct net_device *dev,
                                                            struct netdev_phys_item_id *psid);
@@ -3611,8 +3615,6 @@ static inline bool netif_needs_gso(struct net_device *dev, struct sk_buff *skb,
                                   netdev_features_t features)
 {
        return skb_is_gso(skb) && (!skb_gso_ok(skb, features) ||
-               (dev->netdev_ops->ndo_gso_check &&
-                !dev->netdev_ops->ndo_gso_check(skb, dev)) ||
                unlikely((skb->ip_summed != CHECKSUM_PARTIAL) &&
                         (skb->ip_summed != CHECKSUM_UNNECESSARY)));
 }

diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index 57cccd0052e58dd124ec997174d8cd9ff885be99..903461aa5644ce9d1e366818fa6cbda1ba0cc1b1 100644 (file)
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -1,6 +1,9 @@
 #ifndef __NET_VXLAN_H
 #define __NET_VXLAN_H 1
 
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/if_vlan.h>
 #include <linux/skbuff.h>
 #include <linux/netdevice.h>
 #include <linux/udp.h>
@@ -51,16 +54,33 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
                   __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
                   __be16 src_port, __be16 dst_port, __be32 vni, bool xnet);
 
-static inline bool vxlan_gso_check(struct sk_buff *skb)
+static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
+                                                    netdev_features_t features)
 {
-       if ((skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL) &&
+       u8 l4_hdr = 0;
+
+       if (!skb->encapsulation)
+               return features;
+
+       switch (vlan_get_protocol(skb)) {
+       case htons(ETH_P_IP):
+               l4_hdr = ip_hdr(skb)->protocol;
+               break;
+       case htons(ETH_P_IPV6):
+               l4_hdr = ipv6_hdr(skb)->nexthdr;
+               break;
+       default:
+               return features;;
+       }
+
+       if ((l4_hdr == IPPROTO_UDP) &&
            (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
             skb->inner_protocol != htons(ETH_P_TEB) ||
             (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
              sizeof(struct udphdr) + sizeof(struct vxlanhdr))))
-               return false;
+               return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK);
 
-       return true;
+       return features;
 }
 
 /* IP header + UDP + VXLAN + Ethernet header */

diff --git a/net/core/dev.c b/net/core/dev.c
index 0094562b732a48dd7fc07f41deac6a91973ad86a..683d493aa1bf2225ac0c029ac403841f7d3c740e 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2563,7 +2563,7 @@ static netdev_features_t harmonize_features(struct sk_buff *skb,
 
 netdev_features_t netif_skb_features(struct sk_buff *skb)
 {
-       const struct net_device *dev = skb->dev;
+       struct net_device *dev = skb->dev;
        netdev_features_t features = dev->features;
        u16 gso_segs = skb_shinfo(skb)->gso_segs;
        __be16 protocol = skb->protocol;
@@ -2571,13 +2571,20 @@ netdev_features_t netif_skb_features(struct sk_buff *skb)
        if (gso_segs > dev->gso_max_segs || gso_segs < dev->gso_min_segs)
                features &= ~NETIF_F_GSO_MASK;
 
+       /* If encapsulation offload request, verify we are testing
+        * hardware encapsulation features instead of standard
+        * features for the netdev
+        */
+       if (skb->encapsulation)
+               features &= dev->hw_enc_features;
+
        if (!vlan_tx_tag_present(skb)) {
                if (unlikely(protocol == htons(ETH_P_8021Q) ||
                             protocol == htons(ETH_P_8021AD))) {
                        struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
                        protocol = veh->h_vlan_encapsulated_proto;
                } else {
-                       return harmonize_features(skb, features);
+                       goto finalize;
                }
        }
 
@@ -2595,6 +2602,11 @@ netdev_features_t netif_skb_features(struct sk_buff *skb)
                                                     NETIF_F_HW_VLAN_CTAG_TX |
                                                     NETIF_F_HW_VLAN_STAG_TX);
 
+finalize:
+       if (dev->netdev_ops->ndo_features_check)
+               features &= dev->netdev_ops->ndo_features_check(skb, dev,
+                                                               features);
+
        return harmonize_features(skb, features);
 }
 EXPORT_SYMBOL(netif_skb_features);
@@ -2665,13 +2677,6 @@ static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device
        if (unlikely(!skb))
                goto out_null;
 
-       /* If encapsulation offload request, verify we are testing
-        * hardware encapsulation features instead of standard
-        * features for the netdev
-        */
-       if (skb->encapsulation)
-               features &= dev->hw_enc_features;
-
        if (netif_needs_gso(dev, skb, features)) {
                struct sk_buff *segs;