vxlan: add new fdb alloc and create helpers

- Add new vxlan_fdb_alloc helper
- rename existing vxlan_fdb_create into vxlan_fdb_update:
        because it really creates or updates an existing
        fdb entry
- move new fdb creation into a separate vxlan_fdb_create

Main motivation for this change is to introduce the ability
to decouple vxlan fdb creation and notify, used in a later patch.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 62 insertions, 29 deletions

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index f6bb1d54d4bd..c8d5bfffadef 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -636,9 +636,62 @@ static int vxlan_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff)
         return eth_gro_complete(skb, nhoff + sizeof(struct vxlanhdr));
 }
 
-/* Add new entry to forwarding table -- assumes lock held */
+static struct vxlan_fdb *vxlan_fdb_alloc(struct vxlan_dev *vxlan,
+                                         const u8 *mac, __u16 state,
+                                         __be32 src_vni, __u8 ndm_flags)
+{
+        struct vxlan_fdb *f;
+
+        f = kmalloc(sizeof(*f), GFP_ATOMIC);
+        if (!f)
+                return NULL;
+        f->state = state;
+        f->flags = ndm_flags;
+        f->updated = f->used = jiffies;
+        f->vni = src_vni;
+        INIT_LIST_HEAD(&f->remotes);
+        memcpy(f->eth_addr, mac, ETH_ALEN);
+
+        return f;
+}
+
 static int vxlan_fdb_create(struct vxlan_dev *vxlan,
                             const u8 *mac, union vxlan_addr *ip,
+                            __u16 state, __be16 port, __be32 src_vni,
+                            __be32 vni, __u32 ifindex, __u8 ndm_flags,
+                            struct vxlan_fdb **fdb)
+{
+        struct vxlan_rdst *rd = NULL;
+        struct vxlan_fdb *f;
+        int rc;
+
+        if (vxlan->cfg.addrmax &&
+            vxlan->addrcnt >= vxlan->cfg.addrmax)
+                return -ENOSPC;
+
+        netdev_dbg(vxlan->dev, "add %pM -> %pIS\n", mac, ip);
+        f = vxlan_fdb_alloc(vxlan, mac, state, src_vni, ndm_flags);
+        if (!f)
+                return -ENOMEM;
+
+        rc = vxlan_fdb_append(f, ip, port, vni, ifindex, &rd);
+        if (rc < 0) {
+                kfree(f);
+                return rc;
+        }
+
+        ++vxlan->addrcnt;
+        hlist_add_head_rcu(&f->hlist,
+                           vxlan_fdb_head(vxlan, mac, src_vni));
+
+        *fdb = f;
+
+        return 0;
+}
+
+/* Add new entry to forwarding table -- assumes lock held */
+static int vxlan_fdb_update(struct vxlan_dev *vxlan,
+                            const u8 *mac, union vxlan_addr *ip,
                             __u16 state, __u16 flags,
                             __be16 port, __be32 src_vni, __be32 vni,
                             __u32 ifindex, __u8 ndm_flags)
@@ -687,37 +740,17 @@ static int vxlan_fdb_create(struct vxlan_dev *vxlan,
                 if (!(flags & NLM_F_CREATE))
                         return -ENOENT;
 
-                if (vxlan->cfg.addrmax &&
-                    vxlan->addrcnt >= vxlan->cfg.addrmax)
-                        return -ENOSPC;
-
                 /* Disallow replace to add a multicast entry */
                 if ((flags & NLM_F_REPLACE) &&
                     (is_multicast_ether_addr(mac) || is_zero_ether_addr(mac)))
                         return -EOPNOTSUPP;
 
                 netdev_dbg(vxlan->dev, "add %pM -> %pIS\n", mac, ip);
-                f = kmalloc(sizeof(*f), GFP_ATOMIC);
-                if (!f)
-                        return -ENOMEM;
-
-                notify = 1;
-                f->state = state;
-                f->flags = ndm_flags;
-                f->updated = f->used = jiffies;
-                f->vni = src_vni;
-                INIT_LIST_HEAD(&f->remotes);
-                memcpy(f->eth_addr, mac, ETH_ALEN);
-
-                rc = vxlan_fdb_append(f, ip, port, vni, ifindex, &rd);
-                if (rc < 0) {
-                        kfree(f);
+                rc = vxlan_fdb_create(vxlan, mac, ip, state, port, src_vni,
+                                      vni, ifindex, ndm_flags, &f);
+                if (rc < 0)
                         return rc;
-                }
-
-                ++vxlan->addrcnt;
-                hlist_add_head_rcu(&f->hlist,
-                                   vxlan_fdb_head(vxlan, mac, src_vni));
+                notify = 1;
         }
 
         if (notify) {
@@ -863,7 +896,7 @@ static int vxlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
                 return -EAFNOSUPPORT;
 
         spin_lock_bh(&vxlan->hash_lock);
-        err = vxlan_fdb_create(vxlan, addr, &ip, ndm->ndm_state, flags,
+        err = vxlan_fdb_update(vxlan, addr, &ip, ndm->ndm_state, flags,
                                port, src_vni, vni, ifindex, ndm->ndm_flags);
         spin_unlock_bh(&vxlan->hash_lock);
 
@@ -1006,7 +1039,7 @@ static bool vxlan_snoop(struct net_device *dev,
 
                 /* close off race between vxlan_flush and incoming packets */
                 if (netif_running(dev))
-                        vxlan_fdb_create(vxlan, src_mac, src_ip,
+                        vxlan_fdb_update(vxlan, src_mac, src_ip,
                                          NUD_REACHABLE,
                                          NLM_F_EXCL|NLM_F_CREATE,
                                          vxlan->cfg.dst_port,
@@ -3170,7 +3203,7 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev,
 
         /* create an fdb entry for a valid default destination */
         if (!vxlan_addr_any(&vxlan->default_dst.remote_ip)) {
-                err = vxlan_fdb_create(vxlan, all_zeros_mac,
+                err = vxlan_fdb_update(vxlan, all_zeros_mac,
                                        &vxlan->default_dst.remote_ip,
                                        NUD_REACHABLE | NUD_PERMANENT,
                                        NLM_F_EXCL | NLM_F_CREATE,
@@ -3450,7 +3483,7 @@ static int vxlan_changelink(struct net_device *dev, struct nlattr *tb[],
                                            old_dst.remote_ifindex, 0);
 
                 if (!vxlan_addr_any(&dst->remote_ip)) {
-                        err = vxlan_fdb_create(vxlan, all_zeros_mac,
+                        err = vxlan_fdb_update(vxlan, all_zeros_mac,
                                                &dst->remote_ip,
                                                NUD_REACHABLE | NUD_PERMANENT,
                                                NLM_F_CREATE | NLM_F_APPEND,