IB/core: Add VLAN support for IBoE

Add 802.1q VLAN support to IBoE. The VLAN tag is encoded within the
GID derived from a link local address in the following way:

    GID[11] GID[12] contain the VLAN ID when the GID contains a VLAN.

The 3 bits user priority field of the packets are identical to the 3
bits of the SL.

In case of rdma_cm apps, the TOS field is used to generate the SL
field by doing a shift right of 5 bits effectively taking to 3 MS bits
of the TOS field.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

2 files changed, 48 insertions, 4 deletions

diff --git a/include/rdma/ib_addr.h b/include/rdma/ib_addr.h
index 904ffa92fc93..b5fc9f39122b 100644
--- a/include/rdma/ib_addr.h
+++ b/include/rdma/ib_addr.h
@@ -39,6 +39,7 @@
 #include <linux/if_arp.h>
 #include <linux/netdevice.h>
 #include <linux/socket.h>
+#include <linux/if_vlan.h>
 #include <rdma/ib_verbs.h>
 #include <rdma/ib_pack.h>
 
@@ -129,21 +130,41 @@ static inline int rdma_addr_gid_offset(struct rdma_dev_addr *dev_addr)
         return dev_addr->dev_type == ARPHRD_INFINIBAND ? 4 : 0;
 }
 
-static inline void iboe_mac_to_ll(union ib_gid *gid, u8 *mac)
+static inline void iboe_mac_vlan_to_ll(union ib_gid *gid, u8 *mac, u16 vid)
 {
         memset(gid->raw, 0, 16);
         *((__be32 *) gid->raw) = cpu_to_be32(0xfe800000);
-        gid->raw[12] = 0xfe;
-        gid->raw[11] = 0xff;
+        if (vid < 0x1000) {
+                gid->raw[12] = vid & 0xff;
+                gid->raw[11] = vid >> 8;
+        } else {
+                gid->raw[12] = 0xfe;
+                gid->raw[11] = 0xff;
+        }
         memcpy(gid->raw + 13, mac + 3, 3);
         memcpy(gid->raw + 8, mac, 3);
         gid->raw[8] ^= 2;
 }
 
+static inline u16 rdma_vlan_dev_vlan_id(const struct net_device *dev)
+{
+        return dev->priv_flags & IFF_802_1Q_VLAN ?
+                vlan_dev_vlan_id(dev) : 0xffff;
+}
+
 static inline void iboe_addr_get_sgid(struct rdma_dev_addr *dev_addr,
                                       union ib_gid *gid)
 {
-        iboe_mac_to_ll(gid, dev_addr->src_dev_addr);
+        struct net_device *dev;
+        u16 vid = 0xffff;
+
+        dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
+        if (dev) {
+                vid = rdma_vlan_dev_vlan_id(dev);
+                dev_put(dev);
+        }
+
+        iboe_mac_vlan_to_ll(gid, dev_addr->src_dev_addr, vid);
 }
 
 static inline void rdma_addr_get_sgid(struct rdma_dev_addr *dev_addr, union ib_gid *gid)
@@ -244,4 +265,18 @@ static inline void rdma_get_mcast_mac(struct in6_addr *addr, u8 *mac)
                 mac[i] = addr->s6_addr[i + 10];
 }
 
+static inline u16 rdma_get_vlan_id(union ib_gid *dgid)
+{
+        u16 vid;
+
+        vid = dgid->raw[11] << 8 | dgid->raw[12];
+        return vid < 0x1000 ? vid : 0xffff;
+}
+
+static inline struct net_device *rdma_vlan_dev_real_dev(const struct net_device *dev)
+{
+        return dev->priv_flags & IFF_802_1Q_VLAN ?
+                vlan_dev_real_dev(dev) : 0;
+}
+
 #endif /* IB_ADDR_H */
diff --git a/include/rdma/ib_pack.h b/include/rdma/ib_pack.h
index 6b91d8e7a1fa..b37fe3b10a9d 100644
--- a/include/rdma/ib_pack.h
+++ b/include/rdma/ib_pack.h
@@ -38,6 +38,7 @@
 enum {
         IB_LRH_BYTES  = 8,
         IB_ETH_BYTES  = 14,
+        IB_VLAN_BYTES = 4,
         IB_GRH_BYTES  = 40,
         IB_BTH_BYTES  = 12,
         IB_DETH_BYTES = 8
@@ -219,11 +220,18 @@ struct ib_unpacked_eth {
         __be16  type;
 };
 
+struct ib_unpacked_vlan {
+        __be16  tag;
+        __be16  type;
+};
+
 struct ib_ud_header {
         int                     lrh_present;
         struct ib_unpacked_lrh  lrh;
         int                     eth_present;
         struct ib_unpacked_eth  eth;
+        int                     vlan_present;
+        struct ib_unpacked_vlan vlan;
         int                     grh_present;
         struct ib_unpacked_grh  grh;
         struct ib_unpacked_bth  bth;
@@ -245,6 +253,7 @@ void ib_unpack(const struct ib_field        *desc,
 void ib_ud_header_init(int                  payload_bytes,
                        int                  lrh_present,
                        int                  eth_present,
+                       int                  vlan_present,
                        int                  grh_present,
                        int                  immediate_present,
                        struct ib_ud_header *header);