openvswitch: Increase maximum number of datapath ports.

Use hash table to store ports of datapath. Allow 64K ports per switch.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

1 files changed, 77 insertions, 33 deletions

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index cad39fca75a9..105a0b5adc51 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -116,7 +116,7 @@ static struct datapath *get_dp(struct net *net, int dp_ifindex)
 /* Must be called with rcu_read_lock or RTNL lock. */
 const char *ovs_dp_name(const struct datapath *dp)
 {
-        struct vport *vport = rcu_dereference_rtnl(dp->ports[OVSP_LOCAL]);
+        struct vport *vport = ovs_vport_rtnl_rcu(dp, OVSP_LOCAL);
         return vport->ops->get_name(vport);
 }
 
@@ -127,7 +127,7 @@ static int get_dpifindex(struct datapath *dp)
 
         rcu_read_lock();
 
-        local = rcu_dereference(dp->ports[OVSP_LOCAL]);
+        local = ovs_vport_rcu(dp, OVSP_LOCAL);
         if (local)
                 ifindex = local->ops->get_ifindex(local);
         else
@@ -145,9 +145,30 @@ static void destroy_dp_rcu(struct rcu_head *rcu)
         ovs_flow_tbl_destroy((__force struct flow_table *)dp->table);
         free_percpu(dp->stats_percpu);
         release_net(ovs_dp_get_net(dp));
+        kfree(dp->ports);
         kfree(dp);
 }
 
+static struct hlist_head *vport_hash_bucket(const struct datapath *dp,
+                                            u16 port_no)
+{
+        return &dp->ports[port_no & (DP_VPORT_HASH_BUCKETS - 1)];
+}
+
+struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no)
+{
+        struct vport *vport;
+        struct hlist_node *n;
+        struct hlist_head *head;
+
+        head = vport_hash_bucket(dp, port_no);
+        hlist_for_each_entry_rcu(vport, n, head, dp_hash_node) {
+                if (vport->port_no == port_no)
+                        return vport;
+        }
+        return NULL;
+}
+
 /* Called with RTNL lock and genl_lock. */
 static struct vport *new_vport(const struct vport_parms *parms)
 {
@@ -156,9 +177,9 @@ static struct vport *new_vport(const struct vport_parms *parms)
         vport = ovs_vport_add(parms);
         if (!IS_ERR(vport)) {
                 struct datapath *dp = parms->dp;
+                struct hlist_head *head = vport_hash_bucket(dp, vport->port_no);
 
-                rcu_assign_pointer(dp->ports[parms->port_no], vport);
-                list_add(&vport->node, &dp->port_list);
+                hlist_add_head_rcu(&vport->dp_hash_node, head);
         }
 
         return vport;
@@ -170,8 +191,7 @@ void ovs_dp_detach_port(struct vport *p)
         ASSERT_RTNL();
 
         /* First drop references to device. */
-        list_del(&p->node);
-        rcu_assign_pointer(p->dp->ports[p->port_no], NULL);
+        hlist_del_rcu(&p->dp_hash_node);
 
         /* Then destroy it. */
         ovs_vport_del(p);
@@ -1248,7 +1268,7 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
         struct datapath *dp;
         struct vport *vport;
         struct ovs_net *ovs_net;
-        int err;
+        int err, i;
 
         err = -EINVAL;
         if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
@@ -1261,7 +1281,6 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
         if (dp == NULL)
                 goto err_unlock_rtnl;
 
-        INIT_LIST_HEAD(&dp->port_list);
         ovs_dp_set_net(dp, hold_net(sock_net(skb->sk)));
 
         /* Allocate table. */
@@ -1276,6 +1295,16 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
                 goto err_destroy_table;
         }
 
+        dp->ports = kmalloc(DP_VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
+                        GFP_KERNEL);
+        if (!dp->ports) {
+                err = -ENOMEM;
+                goto err_destroy_percpu;
+        }
+
+        for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
+                INIT_HLIST_HEAD(&dp->ports[i]);
+
         /* Set up our datapath device. */
         parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
         parms.type = OVS_VPORT_TYPE_INTERNAL;
@@ -1290,7 +1319,7 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
                 if (err == -EBUSY)
                         err = -EEXIST;
 
-                goto err_destroy_percpu;
+                goto err_destroy_ports_array;
         }
 
         reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
@@ -1309,7 +1338,9 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
         return 0;
 
 err_destroy_local_port:
-        ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
+        ovs_dp_detach_port(ovs_vport_rtnl(dp, OVSP_LOCAL));
+err_destroy_ports_array:
+        kfree(dp->ports);
 err_destroy_percpu:
         free_percpu(dp->stats_percpu);
 err_destroy_table:
@@ -1326,15 +1357,21 @@ err:
 /* Called with genl_mutex. */
 static void __dp_destroy(struct datapath *dp)
 {
-        struct vport *vport, *next_vport;
+        int i;
 
         rtnl_lock();
-        list_for_each_entry_safe(vport, next_vport, &dp->port_list, node)
-                if (vport->port_no != OVSP_LOCAL)
-                        ovs_dp_detach_port(vport);
+
+        for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
+                struct vport *vport;
+                struct hlist_node *node, *n;
+
+                hlist_for_each_entry_safe(vport, node, n, &dp->ports[i], dp_hash_node)
+                        if (vport->port_no != OVSP_LOCAL)
+                                ovs_dp_detach_port(vport);
+        }
 
         list_del(&dp->list_node);
-        ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
+        ovs_dp_detach_port(ovs_vport_rtnl(dp, OVSP_LOCAL));
 
         /* rtnl_unlock() will wait until all the references to devices that
          * are pending unregistration have been dropped.  We do it here to
@@ -1566,7 +1603,7 @@ static struct vport *lookup_vport(struct net *net,
                 if (!dp)
                         return ERR_PTR(-ENODEV);
 
-                vport = rcu_dereference_rtnl(dp->ports[port_no]);
+                vport = ovs_vport_rtnl_rcu(dp, port_no);
                 if (!vport)
                         return ERR_PTR(-ENOENT);
                 return vport;
@@ -1603,7 +1640,7 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
                 if (port_no >= DP_MAX_PORTS)
                         goto exit_unlock;
 
-                vport = rtnl_dereference(dp->ports[port_no]);
+                vport = ovs_vport_rtnl_rcu(dp, port_no);
                 err = -EBUSY;
                 if (vport)
                         goto exit_unlock;
@@ -1613,7 +1650,7 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
                                 err = -EFBIG;
                                 goto exit_unlock;
                         }
-                        vport = rtnl_dereference(dp->ports[port_no]);
+                        vport = ovs_vport_rtnl(dp, port_no);
                         if (!vport)
                                 break;
                 }
@@ -1755,32 +1792,39 @@ static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
 {
         struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
         struct datapath *dp;
-        u32 port_no;
-        int retval;
+        int bucket = cb->args[0], skip = cb->args[1];
+        int i, j = 0;
 
         dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
         if (!dp)
                 return -ENODEV;
 
         rcu_read_lock();
-        for (port_no = cb->args[0]; port_no < DP_MAX_PORTS; port_no++) {
+        for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
                 struct vport *vport;
-
-                vport = rcu_dereference(dp->ports[port_no]);
-                if (!vport)
-                        continue;
-
-                if (ovs_vport_cmd_fill_info(vport, skb, NETLINK_CB(cb->skb).pid,
-                                            cb->nlh->nlmsg_seq, NLM_F_MULTI,
-                                            OVS_VPORT_CMD_NEW) < 0)
-                        break;
+                struct hlist_node *n;
+
+                j = 0;
+                hlist_for_each_entry_rcu(vport, n, &dp->ports[i], dp_hash_node) {
+                        if (j >= skip &&
+                            ovs_vport_cmd_fill_info(vport, skb,
+                                                    NETLINK_CB(cb->skb).pid,
+                                                    cb->nlh->nlmsg_seq,
+                                                    NLM_F_MULTI,
+                                                    OVS_VPORT_CMD_NEW) < 0)
+                                goto out;
+
+                        j++;
+                }
+                skip = 0;
         }
+out:
         rcu_read_unlock();
 
-        cb->args[0] = port_no;
-        retval = skb->len;
+        cb->args[0] = i;
+        cb->args[1] = j;
 
-        return retval;
+        return skb->len;
 }
 
 static struct genl_ops dp_vport_genl_ops[] = {