net: vlan: add 802.1ad support

Add support for 802.1ad VLAN devices. This mainly consists of checking for
ETH_P_8021AD in addition to ETH_P_8021Q in a couple of places and check
offloading capabilities based on the used protocol.

Configuration is done using "ip link":

# ip link add link eth0 eth0.1000 \
	type vlan proto 802.1ad id 1000
# ip link add link eth0.1000 eth0.1000.1000 \
	type vlan proto 802.1q id 1000

52:54:00:12:34:56 > 92:b1:54:28:e4:8c, ethertype 802.1Q (0x8100), length 106: vlan 1000, p 0, ethertype 802.1Q, vlan 1000, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
    20.1.0.2 > 20.1.0.1: ICMP echo request, id 3003, seq 8, length 64
92:b1:54:28:e4:8c > 52:54:00:12:34:56, ethertype 802.1Q-QinQ (0x88a8), length 106: vlan 1000, p 0, ethertype 802.1Q, vlan 1000, p 0, ethertype IPv4, (tos 0x0, ttl 64, id 47944, offset 0, flags [none], proto ICMP (1), length 84)
    20.1.0.1 > 20.1.0.2: ICMP echo reply, id 3003, seq 8, length 64

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 61 insertions, 16 deletions

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 8086ff9988b1..a78f9390da87 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -162,6 +162,8 @@ static inline bool vlan_hw_offload_capable(netdev_features_t features,
 {
         if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX)
                 return true;
+        if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX)
+                return true;
         return false;
 }
 
@@ -271,9 +273,9 @@ static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
 {
         struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb->data;
 
-        if (veth->h_vlan_proto != htons(ETH_P_8021Q)) {
+        if (veth->h_vlan_proto != htons(ETH_P_8021Q) &&
+            veth->h_vlan_proto != htons(ETH_P_8021AD))
                 return -EINVAL;
-        }
 
         *vlan_tci = ntohs(veth->h_vlan_TCI);
         return 0;
diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index 785913b8983d..cbaa027ef5a7 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -25,6 +25,9 @@ enum {
         NETIF_F_HW_VLAN_CTAG_TX_BIT,    /* Transmit VLAN CTAG HW acceleration */
         NETIF_F_HW_VLAN_CTAG_RX_BIT,    /* Receive VLAN CTAG HW acceleration */
         NETIF_F_HW_VLAN_CTAG_FILTER_BIT,/* Receive filtering on VLAN CTAGs */
+        NETIF_F_HW_VLAN_STAG_TX_BIT,    /* Transmit VLAN STAG HW acceleration */
+        NETIF_F_HW_VLAN_STAG_RX_BIT,    /* Receive VLAN STAG HW acceleration */
+        NETIF_F_HW_VLAN_STAG_FILTER_BIT,/* Receive filtering on VLAN STAGs */
         NETIF_F_VLAN_CHALLENGED_BIT,    /* Device cannot handle VLAN packets */
         NETIF_F_GSO_BIT,                /* Enable software GSO. */
         NETIF_F_LLTX_BIT,               /* LockLess TX - deprecated. Please */
@@ -83,6 +86,9 @@ enum {
 #define NETIF_F_HW_VLAN_CTAG_FILTER __NETIF_F(HW_VLAN_CTAG_FILTER)
 #define NETIF_F_HW_VLAN_CTAG_RX __NETIF_F(HW_VLAN_CTAG_RX)
 #define NETIF_F_HW_VLAN_CTAG_TX __NETIF_F(HW_VLAN_CTAG_TX)
+#define NETIF_F_HW_VLAN_STAG_FILTER __NETIF_F(HW_VLAN_STAG_FILTER)
+#define NETIF_F_HW_VLAN_STAG_RX __NETIF_F(HW_VLAN_STAG_RX)
+#define NETIF_F_HW_VLAN_STAG_TX __NETIF_F(HW_VLAN_STAG_TX)
 #define NETIF_F_IP_CSUM         __NETIF_F(IP_CSUM)
 #define NETIF_F_IPV6_CSUM       __NETIF_F(IPV6_CSUM)
 #define NETIF_F_LLTX            __NETIF_F(LLTX)
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 9922704f08af..e3163544f339 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -250,6 +250,7 @@ enum {
         IFLA_VLAN_FLAGS,
         IFLA_VLAN_EGRESS_QOS,
         IFLA_VLAN_INGRESS_QOS,
+        IFLA_VLAN_PROTOCOL,
         __IFLA_VLAN_MAX,
 };
 
diff --git a/net/8021q/Kconfig b/net/8021q/Kconfig
index 8f7517df41a5..b85a91fa61f1 100644
--- a/net/8021q/Kconfig
+++ b/net/8021q/Kconfig
@@ -3,7 +3,7 @@
 #
 
 config VLAN_8021Q
-        tristate "802.1Q VLAN Support"
+        tristate "802.1Q/802.1ad VLAN Support"
         ---help---
           Select this and you will be able to create 802.1Q VLAN interfaces
           on your ethernet interfaces.  802.1Q VLAN supports almost
diff --git a/net/8021q/vlan.h b/net/8021q/vlan.h
index 245de9653db0..abc9cb631c47 100644
--- a/net/8021q/vlan.h
+++ b/net/8021q/vlan.h
@@ -91,6 +91,7 @@ static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
 
 enum vlan_protos {
         VLAN_PROTO_8021Q        = 0,
+        VLAN_PROTO_8021AD,
         VLAN_PROTO_NUM,
 };
 
@@ -116,6 +117,8 @@ static inline unsigned int vlan_proto_idx(__be16 proto)
         switch (proto) {
         case __constant_htons(ETH_P_8021Q):
                 return VLAN_PROTO_8021Q;
+        case __constant_htons(ETH_P_8021AD):
+                return VLAN_PROTO_8021AD;
         default:
                 BUG();
         }
diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c
index bdb0b9d2e9cf..ebfa2fceb88b 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -194,6 +194,18 @@ struct vlan_vid_info {
         int refcount;
 };
 
+static bool vlan_hw_filter_capable(const struct net_device *dev,
+                                     const struct vlan_vid_info *vid_info)
+{
+        if (vid_info->proto == htons(ETH_P_8021Q) &&
+            dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
+                return true;
+        if (vid_info->proto == htons(ETH_P_8021AD) &&
+            dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
+                return true;
+        return false;
+}
+
 static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
                                                __be16 proto, u16 vid)
 {
@@ -231,8 +243,7 @@ static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
         if (!vid_info)
                 return -ENOMEM;
 
-        if (proto == htons(ETH_P_8021Q) &&
-            dev->features & NETIF_F_HW_VLAN_CTAG_FILTER) {
+        if (vlan_hw_filter_capable(dev, vid_info)) {
                 err =  ops->ndo_vlan_rx_add_vid(dev, proto, vid);
                 if (err) {
                         kfree(vid_info);
@@ -290,8 +301,7 @@ static void __vlan_vid_del(struct vlan_info *vlan_info,
         u16 vid = vid_info->vid;
         int err;
 
-        if (proto == htons(ETH_P_8021Q) &&
-            dev->features & NETIF_F_HW_VLAN_CTAG_FILTER) {
+        if (vlan_hw_filter_capable(dev, vid_info)) {
                 err = ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
                 if (err) {
                         pr_warn("failed to kill vid %04x/%d for device %s\n",
diff --git a/net/8021q/vlan_netlink.c b/net/8021q/vlan_netlink.c
index a1a956ab39a5..309129732285 100644
--- a/net/8021q/vlan_netlink.c
+++ b/net/8021q/vlan_netlink.c
@@ -23,6 +23,7 @@ static const struct nla_policy vlan_policy[IFLA_VLAN_MAX + 1] = {
         [IFLA_VLAN_FLAGS]       = { .len = sizeof(struct ifla_vlan_flags) },
         [IFLA_VLAN_EGRESS_QOS]  = { .type = NLA_NESTED },
         [IFLA_VLAN_INGRESS_QOS] = { .type = NLA_NESTED },
+        [IFLA_VLAN_PROTOCOL]    = { .type = NLA_U16 },
 };
 
 static const struct nla_policy vlan_map_policy[IFLA_VLAN_QOS_MAX + 1] = {
@@ -53,6 +54,16 @@ static int vlan_validate(struct nlattr *tb[], struct nlattr *data[])
         if (!data)
                 return -EINVAL;
 
+        if (data[IFLA_VLAN_PROTOCOL]) {
+                switch (nla_get_be16(data[IFLA_VLAN_PROTOCOL])) {
+                case __constant_htons(ETH_P_8021Q):
+                case __constant_htons(ETH_P_8021AD):
+                        break;
+                default:
+                        return -EPROTONOSUPPORT;
+                }
+        }
+
         if (data[IFLA_VLAN_ID]) {
                 id = nla_get_u16(data[IFLA_VLAN_ID]);
                 if (id >= VLAN_VID_MASK)
@@ -107,6 +118,7 @@ static int vlan_newlink(struct net *src_net, struct net_device *dev,
 {
         struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
         struct net_device *real_dev;
+        __be16 proto;
         int err;
 
         if (!data[IFLA_VLAN_ID])
@@ -118,7 +130,12 @@ static int vlan_newlink(struct net *src_net, struct net_device *dev,
         if (!real_dev)
                 return -ENODEV;
 
-        vlan->vlan_proto = htons(ETH_P_8021Q);
+        if (data[IFLA_VLAN_PROTOCOL])
+                proto = nla_get_be16(data[IFLA_VLAN_PROTOCOL]);
+        else
+                proto = htons(ETH_P_8021Q);
+
+        vlan->vlan_proto = proto;
         vlan->vlan_id    = nla_get_u16(data[IFLA_VLAN_ID]);
         vlan->real_dev   = real_dev;
         vlan->flags      = VLAN_FLAG_REORDER_HDR;
@@ -152,7 +169,8 @@ static size_t vlan_get_size(const struct net_device *dev)
 {
         struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 
-        return nla_total_size(2) +      /* IFLA_VLAN_ID */
+        return nla_total_size(2) +      /* IFLA_VLAN_PROTOCOL */
+               nla_total_size(2) +      /* IFLA_VLAN_ID */
                sizeof(struct ifla_vlan_flags) + /* IFLA_VLAN_FLAGS */
                vlan_qos_map_size(vlan->nr_ingress_mappings) +
                vlan_qos_map_size(vlan->nr_egress_mappings);
@@ -167,7 +185,8 @@ static int vlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
         struct nlattr *nest;
         unsigned int i;
 
-        if (nla_put_u16(skb, IFLA_VLAN_ID, vlan_dev_priv(dev)->vlan_id))
+        if (nla_put_be16(skb, IFLA_VLAN_PROTOCOL, vlan->vlan_proto) ||
+            nla_put_u16(skb, IFLA_VLAN_ID, vlan->vlan_id))
                 goto nla_put_failure;
         if (vlan->flags) {
                 f.flags = vlan->flags;
diff --git a/net/core/dev.c b/net/core/dev.c
index 3a12ee132b59..fad4c385f7a1 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2212,7 +2212,7 @@ __be16 skb_network_protocol(struct sk_buff *skb)
         __be16 type = skb->protocol;
         int vlan_depth = ETH_HLEN;
 
-        while (type == htons(ETH_P_8021Q)) {
+        while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
                 struct vlan_hdr *vh;
 
                 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
@@ -2428,20 +2428,22 @@ netdev_features_t netif_skb_features(struct sk_buff *skb)
         if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
                 features &= ~NETIF_F_GSO_MASK;
 
-        if (protocol == htons(ETH_P_8021Q)) {
+        if (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 if (!vlan_tx_tag_present(skb)) {
                 return harmonize_features(skb, protocol, features);
         }
 
-        features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX);
+        features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
+                                               NETIF_F_HW_VLAN_STAG_TX);
 
-        if (protocol != htons(ETH_P_8021Q)) {
+        if (protocol != htons(ETH_P_8021Q) && protocol != htons(ETH_P_8021AD)) {
                 return harmonize_features(skb, protocol, features);
         } else {
                 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
-                                NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX;
+                                NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
+                                NETIF_F_HW_VLAN_STAG_TX;
                 return harmonize_features(skb, protocol, features);
         }
 }
@@ -3360,6 +3362,7 @@ static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
         case __constant_htons(ETH_P_IP):
         case __constant_htons(ETH_P_IPV6):
         case __constant_htons(ETH_P_8021Q):
+        case __constant_htons(ETH_P_8021AD):
                 return true;
         default:
                 return false;
@@ -3400,7 +3403,8 @@ another_round:
 
         __this_cpu_inc(softnet_data.processed);
 
-        if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
+        if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
+            skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
                 skb = vlan_untag(skb);
                 if (unlikely(!skb))
                         goto unlock;