Hi, On Thu, 2015-07-30 at 11:12 -0700, Joe Stringer wrote: > diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c > index e50678d..4a62ed4 100644 > --- a/net/openvswitch/actions.c > +++ b/net/openvswitch/actions.c > @@ -22,6 +22,7 @@ > #include <linux/in.h> > #include <linux/ip.h> > #include <linux/openvswitch.h> > +#include <linux/netfilter_ipv6.h> > #include <linux/sctp.h> > #include <linux/tcp.h> > #include <linux/udp.h> > @@ -29,6 +30,7 @@ > #include <linux/if_arp.h> > #include <linux/if_vlan.h> > > +#include <net/dst.h> > #include <net/ip.h> > #include <net/ipv6.h> > #include <net/checksum.h> > @@ -38,6 +40,7 @@ > > #include "datapath.h" > #include "flow.h" > +#include "conntrack.h" > #include "vport.h" > > static int do_execute_actions(struct datapath *dp, struct sk_buff > *skb, > @@ -52,6 +55,16 @@ struct deferred_action { > struct sw_flow_key pkt_key; > }; > > +struct ovs_frag_data { > + struct dst_entry *dst;
As this is a temporary storage area for skb data, we could simply use an unsigned long here and don't need to force a reference on the dst_entry in ovs_vport_output. > + struct vport *vport; > + struct sw_flow_key *key; > + struct ovs_skb_cb cb; > + __be16 vlan_proto; > +}; > + > +static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage); > + > #define DEFERRED_ACTION_FIFO_SIZE 10 > struct action_fifo { > int head; > @@ -594,14 +607,136 @@ static int set_sctp(struct sk_buff *skb, struct > sw_flow_key *flow_key, > return 0; > } > > -static void do_output(struct datapath *dp, struct sk_buff *skb, int > out_port) > +/* Given an IP frame, reconstruct its MAC header. */ > +static void ovs_setup_l2_header(struct sk_buff *skb, > + const struct ovs_frag_data *data) > +{ > + struct sw_flow_key *key = data->key; > + > + skb_push(skb, ETH_HLEN); > + skb_reset_mac_header(skb); > + > + ether_addr_copy(eth_hdr(skb)->h_source, key->eth.src); > + ether_addr_copy(eth_hdr(skb)->h_dest, key->eth.dst); > + eth_hdr(skb)->h_proto = key->eth.type; > + > + if ((data->key->eth.tci & htons(VLAN_TAG_PRESENT)) && > + !skb_vlan_tag_present(skb)) > + __vlan_hwaccel_put_tag(skb, data->vlan_proto, > + ntohs(key->eth.tci)); > +} > + > +static void prepare_frag(struct vport *vport, struct sw_flow_key > *key, > + struct sk_buff *skb) > +{ > + unsigned int hlen = ETH_HLEN; > + struct ovs_frag_data *data; > + > + data = this_cpu_ptr(&ovs_frag_data_storage); > + data->dst = skb_dst(skb); If data->dst is unsigned long, we could simply use an assignment: data->dst = skb->_skb_refdst; At this point we never leave rcu_read_lock section, so we are safe, maybe we can add a comment for that. > + data->vport = vport; > + data->key = key; > + data->cb = *OVS_CB(skb); > + > + if (key->eth.tci & htons(VLAN_TAG_PRESENT)) { > + if (skb_vlan_tag_present(skb)) { > + data->vlan_proto = skb->vlan_proto; > + } else { > + data->vlan_proto = vlan_eth_hdr(skb) > ->h_vlan_proto; > + hlen += VLAN_HLEN; > + } > + } > + > + memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); > + skb_pull(skb, hlen); > +} > + > +static int ovs_vport_output(struct sock *sock, struct sk_buff *skb) > +{ > + struct ovs_frag_data *data = > this_cpu_ptr(&ovs_frag_data_storage); > + struct vport *vport = data->vport; > + > + skb_dst_drop(skb); > + skb_dst_set(skb, dst_clone(data->dst)); We don't need to refcount the dst here, then. > + *OVS_CB(skb) = data->cb; > + > + ovs_setup_l2_header(skb, data); > + ovs_vport_send(vport, skb); > + > + return 0; > +} > + > +unsigned int > +ovs_dst_get_mtu(const struct dst_entry *dst) > +{ > + return dst->dev->mtu; > +} > + > +static struct dst_ops ovs_dst_ops = { > + .family = AF_UNSPEC, > + .mtu = ovs_dst_get_mtu, > +}; > + > +static void do_output(struct datapath *dp, struct sk_buff *skb, int > out_port, > + struct sw_flow_key *key) > { > struct vport *vport = ovs_vport_rcu(dp, out_port); > > - if (likely(vport)) > - ovs_vport_send(vport, skb); > - else > + if (likely(vport)) { > + unsigned int mru = OVS_CB(skb)->mru; > + struct dst_entry *orig_dst = dst_clone(skb_dst(skb)); > + > + if (!mru || (skb->len <= mru + ETH_HLEN)) { > + ovs_vport_send(vport, skb); > + } else if (!vport->dev) { > + WARN_ONCE(1, "Cannot fragment packets to > vport %s\n", > + vport->ops->get_name(vport)); > + kfree_skb(skb); > + } else if (mru > vport->dev->mtu) { > + kfree_skb(skb); > + } else if (key->eth.type == htons(ETH_P_IP)) { > + struct dst_entry ovs_dst; > + > + prepare_frag(vport, key, skb); > + dst_init(&ovs_dst, &ovs_dst_ops, vport->dev, > + 1, DST_OBSOLETE_NONE, DST_NOCOUNT); I don't think we should take a ref on the netdev here. dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1, DST_OBSOLETE_NONE, DST_NOCOUNT); ovs_dst.dev = vport->dev; > + > + skb_dst_drop(skb); > + skb_dst_set_noref(skb, &ovs_dst); > + IPCB(skb)->frag_max_size = mru; > + > + ip_do_fragment(skb->sk, skb, > ovs_vport_output); > + dev_put(ovs_dst.dev); Can be removed then. It seems a little strange to leave the skb->dst attached to the skb but drop the reference from the netdevice here. Maybe a comment would make sense, otherwise it smells fishy. > + } else if (key->eth.type == htons(ETH_P_IPV6)) { > + const struct nf_ipv6_ops *v6ops = > nf_get_ipv6_ops(); > + struct rt6_info ovs_rt; > + > + if (!v6ops) { > + kfree_skb(skb); > + goto exit; > + } > + > + prepare_frag(vport, key, skb); > + memset(&ovs_rt, 0, sizeof(ovs_rt)); > + dst_init(&ovs_rt.dst, &ovs_dst_ops, vport > ->dev, > + 1, DST_OBSOLETE_NONE, DST_NOCOUNT); > + > + skb_dst_drop(skb); > + skb_dst_set_noref(skb, &ovs_rt.dst); > + IP6CB(skb)->frag_max_size = mru; > + > + v6ops->fragment(skb->sk, skb, > ovs_vport_output); > + dev_put(ovs_rt.dst.dev); Same thought applies here. > + } else { > + WARN_ONCE(1, "Failed fragment to %s: MRU=%d, > MTU=%d.", > + ovs_vport_name(vport), mru, vport > ->dev->mtu); > + kfree_skb(skb); > + } > +exit: > + dst_release(orig_dst); > + } else { > kfree_skb(skb); > + } > } > > static int output_userspace(struct datapath *dp, struct sk_buff *skb, > @@ -615,6 +750,10 @@ static int output_userspace(struct datapath *dp, > struct sk_buff *skb, > > memset(&upcall, 0, sizeof(upcall)); > upcall.cmd = OVS_PACKET_CMD_ACTION; > + upcall.userdata = NULL; > + upcall.portid = 0; > + upcall.egress_tun_info = NULL; > + upcall.mru = OVS_CB(skb)->mru; > > for (a = nla_data(attr), rem = nla_len(attr); rem > 0; > a = nla_next(a, &rem)) { > @@ -874,7 +1013,7 @@ static int do_execute_actions(struct datapath > *dp, struct sk_buff *skb, > struct sk_buff *out_skb = skb_clone(skb, > GFP_ATOMIC); > > if (out_skb) > - do_output(dp, out_skb, prev_port); > + do_output(dp, out_skb, prev_port, > key); > > prev_port = -1; > } > @@ -931,16 +1070,25 @@ static int do_execute_actions(struct datapath > *dp, struct sk_buff *skb, > case OVS_ACTION_ATTR_SAMPLE: > err = sample(dp, skb, key, a, attr, len); > break; > + > + case OVS_ACTION_ATTR_CT: > + err = ovs_ct_execute(skb, key, nla_data(a)); > + break; > } > > if (unlikely(err)) { > - kfree_skb(skb); > + /* Hide stolen fragments from user space. */ > + if (err == -EINPROGRESS) > + err = 0; > + else > + kfree_skb(skb); > + > return err; > } > } > > if (prev_port != -1) > - do_output(dp, skb, prev_port); > + do_output(dp, skb, prev_port, key); > else > consume_skb(skb); > Bye, Hannes -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html