datapath: fix dp check in ovs_dp_reset_user_features
[sliver-openvswitch.git] / datapath / datapath.c
index 08562a3..a7839a1 100644 (file)
@@ -56,6 +56,7 @@
 
 #include "datapath.h"
 #include "flow.h"
+#include "flow_table.h"
 #include "flow_netlink.h"
 #include "vlan.h"
 #include "vport-internal_dev.h"
@@ -110,10 +111,9 @@ int lockdep_ovsl_is_held(void)
 #endif
 
 static struct vport *new_vport(const struct vport_parms *);
-static int queue_gso_packets(struct net *, int dp_ifindex, struct sk_buff *,
+static int queue_gso_packets(struct datapath *dp, struct sk_buff *,
                             const struct dp_upcall_info *);
-static int queue_userspace_packet(struct net *, int dp_ifindex,
-                                 struct sk_buff *,
+static int queue_userspace_packet(struct datapath *dp, struct sk_buff *,
                                  const struct dp_upcall_info *);
 
 /* Must be called with rcu_read_lock or ovs_mutex. */
@@ -163,7 +163,6 @@ static void destroy_dp_rcu(struct rcu_head *rcu)
 {
        struct datapath *dp = container_of(rcu, struct datapath, rcu);
 
-       ovs_flow_tbl_destroy(&dp->table);
        free_percpu(dp->stats_percpu);
        release_net(ovs_dp_get_net(dp));
        kfree(dp->ports);
@@ -279,7 +278,6 @@ int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
                  const struct dp_upcall_info *upcall_info)
 {
        struct dp_stats_percpu *stats;
-       int dp_ifindex;
        int err;
 
        if (upcall_info->portid == 0) {
@@ -287,16 +285,10 @@ int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
                goto err;
        }
 
-       dp_ifindex = get_dpifindex(dp);
-       if (!dp_ifindex) {
-               err = -ENODEV;
-               goto err;
-       }
-
        if (!skb_is_gso(skb))
-               err = queue_userspace_packet(ovs_dp_get_net(dp), dp_ifindex, skb, upcall_info);
+               err = queue_userspace_packet(dp, skb, upcall_info);
        else
-               err = queue_gso_packets(ovs_dp_get_net(dp), dp_ifindex, skb, upcall_info);
+               err = queue_gso_packets(dp, skb, upcall_info);
        if (err)
                goto err;
 
@@ -312,8 +304,7 @@ err:
        return err;
 }
 
-static int queue_gso_packets(struct net *net, int dp_ifindex,
-                            struct sk_buff *skb,
+static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb,
                             const struct dp_upcall_info *upcall_info)
 {
        unsigned short gso_type = skb_shinfo(skb)->gso_type;
@@ -322,14 +313,14 @@ static int queue_gso_packets(struct net *net, int dp_ifindex,
        struct sk_buff *segs, *nskb;
        int err;
 
-       segs = __skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM, false);
+       segs = __skb_gso_segment(skb, NETIF_F_SG, false);
        if (IS_ERR(segs))
                return PTR_ERR(segs);
 
        /* Queue all of the segments. */
        skb = segs;
        do {
-               err = queue_userspace_packet(net, dp_ifindex, skb, upcall_info);
+               err = queue_userspace_packet(dp, skb, upcall_info);
                if (err)
                        break;
 
@@ -382,11 +373,11 @@ static size_t key_attr_size(void)
                + nla_total_size(28); /* OVS_KEY_ATTR_ND */
 }
 
-static size_t upcall_msg_size(const struct sk_buff *skb,
-                             const struct nlattr *userdata)
+static size_t upcall_msg_size(const struct nlattr *userdata,
+                             unsigned int hdrlen)
 {
        size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
-               + nla_total_size(skb->len) /* OVS_PACKET_ATTR_PACKET */
+               + nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
                + nla_total_size(key_attr_size()); /* OVS_PACKET_ATTR_KEY */
 
        /* OVS_PACKET_ATTR_USERDATA */
@@ -396,8 +387,7 @@ static size_t upcall_msg_size(const struct sk_buff *skb,
        return size;
 }
 
-static int queue_userspace_packet(struct net *net, int dp_ifindex,
-                                 struct sk_buff *skb,
+static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
                                  const struct dp_upcall_info *upcall_info)
 {
        struct ovs_header *upcall;
@@ -406,12 +396,17 @@ static int queue_userspace_packet(struct net *net, int dp_ifindex,
        struct nlattr *nla;
        struct genl_info info = {
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(3,14,0)
-               .dst_sk = net->genl_sock,
+               .dst_sk = ovs_dp_get_net(dp)->genl_sock,
 #endif
                .snd_portid = upcall_info->portid,
        };
        size_t len;
-       int err;
+       unsigned int hlen;
+       int err, dp_ifindex;
+
+       dp_ifindex = get_dpifindex(dp);
+       if (!dp_ifindex)
+               return -ENODEV;
 
        if (vlan_tx_tag_present(skb)) {
                nskb = skb_clone(skb, GFP_ATOMIC);
@@ -432,7 +427,21 @@ static int queue_userspace_packet(struct net *net, int dp_ifindex,
                goto out;
        }
 
-       len = upcall_msg_size(skb, upcall_info->userdata);
+       /* Complete checksum if needed */
+       if (skb->ip_summed == CHECKSUM_PARTIAL &&
+           (err = skb_checksum_help(skb)))
+               goto out;
+
+       /* Older versions of OVS user space enforce alignment of the last
+        * Netlink attribute to NLA_ALIGNTO which would require extensive
+        * padding logic. Only perform zerocopy if padding is not required.
+        */
+       if (dp->user_features & OVS_DP_F_UNALIGNED)
+               hlen = skb_zerocopy_headlen(skb);
+       else
+               hlen = skb->len;
+
+       len = upcall_msg_size(upcall_info->userdata, hlen);
        user_skb = genlmsg_new_unicast(len, &info, GFP_ATOMIC);
        if (!user_skb) {
                err = -ENOMEM;
@@ -452,13 +461,27 @@ static int queue_userspace_packet(struct net *net, int dp_ifindex,
                          nla_len(upcall_info->userdata),
                          nla_data(upcall_info->userdata));
 
-       nla = __nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, skb->len);
+       /* Only reserve room for attribute header, packet data is added
+        * in skb_zerocopy() */
+       if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
+               err = -ENOBUFS;
+               goto out;
+       }
+       nla->nla_len = nla_attr_size(skb->len);
+
+       skb_zerocopy(user_skb, skb, skb->len, hlen);
+
+       /* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
+       if (!(dp->user_features & OVS_DP_F_UNALIGNED)) {
+               size_t plen = NLA_ALIGN(user_skb->len) - user_skb->len;
 
-       skb_copy_and_csum_dev(skb, nla_data(nla));
+               if (plen > 0)
+                       memset(skb_put(user_skb, plen), 0, plen);
+       }
 
-       genlmsg_end(user_skb, upcall);
-       err = genlmsg_unicast(net, user_skb, upcall_info->portid);
+       ((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
 
+       err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
 out:
        kfree_skb(nskb);
        return err;
@@ -842,11 +865,8 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
                        goto err_unlock_ovs;
 
                /* The unmasked key has to be the same for flow updates. */
-               error = -EINVAL;
-               if (!ovs_flow_cmp_unmasked_key(flow, &match)) {
-                       OVS_NLERR("Flow modification message rejected, unmasked key does not match.\n");
+               if (!ovs_flow_cmp_unmasked_key(flow, &match))
                        goto err_unlock_ovs;
-               }
 
                /* Update actions. */
                old_acts = ovsl_dereference(flow->sf_acts);
@@ -1069,6 +1089,7 @@ static size_t ovs_dp_cmd_msg_size(void)
        msgsize += nla_total_size(IFNAMSIZ);
        msgsize += nla_total_size(sizeof(struct ovs_dp_stats));
        msgsize += nla_total_size(sizeof(struct ovs_dp_megaflow_stats));
+       msgsize += nla_total_size(sizeof(u32)); /* OVS_DP_ATTR_USER_FEATURES */
 
        return msgsize;
 }
@@ -1153,6 +1174,18 @@ static struct datapath *lookup_datapath(struct net *net,
        return dp ? dp : ERR_PTR(-ENODEV);
 }
 
+static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
+{
+       struct datapath *dp;
+
+       dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
+       if (IS_ERR(dp))
+               return;
+
+       WARN(dp->user_features, "Dropping previously announced user features\n");
+       dp->user_features = 0;
+}
+
 static void ovs_dp_change(struct datapath *dp, struct nlattr **a)
 {
        if (a[OVS_DP_ATTR_USER_FEATURES])
@@ -1219,6 +1252,15 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
                if (err == -EBUSY)
                        err = -EEXIST;
 
+               if (err == -EEXIST) {
+                       /* An outdated user space instance that does not understand
+                        * the concept of user_features has attempted to create a new
+                        * datapath and is likely to reuse it. Drop all user features.
+                        */
+                       if (info->genlhdr->version < OVS_DP_VER_FEATURES)
+                               ovs_dp_reset_user_features(skb, info);
+               }
+
                goto err_destroy_ports_array;
        }
 
@@ -1242,7 +1284,7 @@ err_destroy_ports_array:
 err_destroy_percpu:
        free_percpu(dp->stats_percpu);
 err_destroy_table:
-       ovs_flow_tbl_destroy(&dp->table);
+       ovs_flow_tbl_destroy(&dp->table, false);
 err_free_dp:
        release_net(ovs_dp_get_net(dp));
        kfree(dp);
@@ -1269,10 +1311,13 @@ static void __dp_destroy(struct datapath *dp)
        list_del_rcu(&dp->list_node);
 
        /* OVSP_LOCAL is datapath internal port. We need to make sure that
-        * all port in datapath are destroyed first before freeing datapath.
-        */
+        * all ports in datapath are destroyed first before freeing datapath.
+        */
        ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
 
+       /* RCU destroy the flow table */
+       ovs_flow_tbl_destroy(&dp->table, true);
+
        call_rcu(&dp->rcu, destroy_dp_rcu);
 }
 
@@ -1722,11 +1767,12 @@ static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
        int bucket = cb->args[0], skip = cb->args[1];
        int i, j = 0;
 
+       rcu_read_lock();
        dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
-       if (!dp)
+       if (!dp) {
+               rcu_read_unlock();
                return -ENODEV;
-
-       rcu_read_lock();
+       }
        for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
                struct vport *vport;