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Date: Tue, 26 Aug 2014 22:19:15 -0700
From: Andy Zhou <azhou@...ira.com>
To: Tom Herbert <therbert@...gle.com>
Cc: David Miller <davem@...emloft.net>,
Linux Netdev List <netdev@...r.kernel.org>
Subject: Re: [net-next v3 2/3] vxlan: Refactor vxlan driver to make use of the
common UDP tunnel functions.
On Tue, Aug 26, 2014 at 9:14 PM, Tom Herbert <therbert@...gle.com> wrote:
>
>
> On Tue, Aug 26, 2014 at 8:35 PM, Andy Zhou <azhou@...ira.com> wrote:
>> Signed-off-by: Andy Zhou <azhou@...ira.com>
>> ---
>> drivers/net/vxlan.c | 199
>> ++++++++++++-----------------------------
>> include/net/vxlan.h | 16 ++--
>> net/openvswitch/vport-vxlan.c | 6 +-
>> 3 files changed, 68 insertions(+), 153 deletions(-)
>>
>> diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
>> index beb377b..f1f1c48 100644
>> --- a/drivers/net/vxlan.c
>> +++ b/drivers/net/vxlan.c
>> @@ -42,6 +42,7 @@
>> #include <net/netns/generic.h>
>> #include <net/vxlan.h>
>> #include <net/protocol.h>
>> +#include <net/udp_tunnel.h>
>> #if IS_ENABLED(CONFIG_IPV6)
>> #include <net/ipv6.h>
>> #include <net/addrconf.h>
>> @@ -277,13 +278,7 @@ static inline struct vxlan_rdst
>> *first_remote_rtnl(struct vxlan_fdb *fdb)
>> /* Find VXLAN socket based on network namespace and UDP port */
>> static struct vxlan_sock *vxlan_find_sock(struct net *net, __be16 port)
>> {
>> - struct vxlan_sock *vs;
>> -
>> - hlist_for_each_entry_rcu(vs, vs_head(net, port), hlist) {
>> - if (inet_sk(vs->sock->sk)->inet_sport == port)
>> - return vs;
>> - }
>> - return NULL;
>> + return (struct vxlan_sock *)udp_tunnel_find_sock(net, port);
>
> It seems incorrect to assume that the socket returned is vxlan, presumably
> this could be some other type of tunnel socket.
>
If I drop udp_tunnel_find_sock API from last patch, then this should
not be an issue any more right?
vxlan driver will just keep track of its own open sock.
>> }
>>
>> static struct vxlan_dev *vxlan_vs_find_vni(struct vxlan_sock *vs, u32 id)
>> @@ -636,7 +631,7 @@ static int vxlan_gro_complete(struct sk_buff *skb, int
>> nhoff)
>> static void vxlan_notify_add_rx_port(struct vxlan_sock *vs)
>> {
>> struct net_device *dev;
>> - struct sock *sk = vs->sock->sk;
>> + struct sock *sk = vs->uts.sock->sk;
>> struct net *net = sock_net(sk);
>> sa_family_t sa_family = sk->sk_family;
>> __be16 port = inet_sk(sk)->inet_sport;
>> @@ -661,7 +656,7 @@ static void vxlan_notify_add_rx_port(struct vxlan_sock
>> *vs)
>> static void vxlan_notify_del_rx_port(struct vxlan_sock *vs)
>> {
>> struct net_device *dev;
>> - struct sock *sk = vs->sock->sk;
>> + struct sock *sk = vs->uts.sock->sk;
>> struct net *net = sock_net(sk);
>> sa_family_t sa_family = sk->sk_family;
>> __be16 port = inet_sk(sk)->inet_sport;
>> @@ -1053,7 +1048,7 @@ static void vxlan_sock_hold(struct vxlan_sock *vs)
>>
>> void vxlan_sock_release(struct vxlan_sock *vs)
>> {
>> - struct sock *sk = vs->sock->sk;
>> + struct sock *sk = vs->uts.sock->sk;
>> struct net *net = sock_net(sk);
>> struct vxlan_net *vn = net_generic(net, vxlan_net_id);
>>
>> @@ -1062,7 +1057,6 @@ void vxlan_sock_release(struct vxlan_sock *vs)
>>
>> spin_lock(&vn->sock_lock);
>> hlist_del_rcu(&vs->hlist);
>> - rcu_assign_sk_user_data(vs->sock->sk, NULL);
>> vxlan_notify_del_rx_port(vs);
>> spin_unlock(&vn->sock_lock);
>>
>> @@ -1078,7 +1072,7 @@ static void vxlan_igmp_join(struct work_struct
>> *work)
>> {
>> struct vxlan_dev *vxlan = container_of(work, struct vxlan_dev,
>> igmp_join);
>> struct vxlan_sock *vs = vxlan->vn_sock;
>> - struct sock *sk = vs->sock->sk;
>> + struct sock *sk = vs->uts.sock->sk;
>> union vxlan_addr *ip = &vxlan->default_dst.remote_ip;
>> int ifindex = vxlan->default_dst.remote_ifindex;
>>
>> @@ -1107,7 +1101,7 @@ static void vxlan_igmp_leave(struct work_struct
>> *work)
>> {
>> struct vxlan_dev *vxlan = container_of(work, struct vxlan_dev,
>> igmp_leave);
>> struct vxlan_sock *vs = vxlan->vn_sock;
>> - struct sock *sk = vs->sock->sk;
>> + struct sock *sk = vs->uts.sock->sk;
>> union vxlan_addr *ip = &vxlan->default_dst.remote_ip;
>> int ifindex = vxlan->default_dst.remote_ifindex;
>>
>> @@ -1338,7 +1332,6 @@ out:
>> }
>>
>> #if IS_ENABLED(CONFIG_IPV6)
>> -
>> static struct sk_buff *vxlan_na_create(struct sk_buff *request,
>> struct neighbour *n, bool isrouter)
>> {
>> @@ -1572,13 +1565,6 @@ static bool route_shortcircuit(struct net_device
>> *dev, struct sk_buff *skb)
>> return false;
>> }
>>
>> -static inline struct sk_buff *vxlan_handle_offloads(struct sk_buff *skb,
>> - bool udp_csum)
>> -{
>> - int type = udp_csum ? SKB_GSO_UDP_TUNNEL_CSUM :
>> SKB_GSO_UDP_TUNNEL;
>> - return iptunnel_handle_offloads(skb, udp_csum, type);
>> -}
>> -
>> #if IS_ENABLED(CONFIG_IPV6)
>> static int vxlan6_xmit_skb(struct vxlan_sock *vs,
>> struct dst_entry *dst, struct sk_buff *skb,
>> @@ -1587,13 +1573,13 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
>> __be16 src_port, __be16 dst_port, __be32 vni,
>> bool xnet)
>> {
>> - struct ipv6hdr *ip6h;
>> struct vxlanhdr *vxh;
>> - struct udphdr *uh;
>> int min_headroom;
>> int err;
>>
>> - skb = vxlan_handle_offloads(skb,
>> !udp_get_no_check6_tx(vs->sock->sk));
>> + skb = udp_tunnel_handle_offloads(skb,
>> + !udp_get_no_check6_tx(
>> + vs->uts.sock->sk));
>> if (IS_ERR(skb))
>> return -EINVAL;
>>
>> @@ -1621,38 +1607,8 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
>> vxh->vx_flags = htonl(VXLAN_FLAGS);
>> vxh->vx_vni = vni;
>>
>> - __skb_push(skb, sizeof(*uh));
>> - skb_reset_transport_header(skb);
>> - uh = udp_hdr(skb);
>> -
>> - uh->dest = dst_port;
>> - uh->source = src_port;
>> -
>> - uh->len = htons(skb->len);
>> -
>> - memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
>> - IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE |
>> IPSKB_XFRM_TRANSFORMED |
>> - IPSKB_REROUTED);
>> - skb_dst_set(skb, dst);
>> -
>> - udp6_set_csum(udp_get_no_check6_tx(vs->sock->sk), skb,
>> - saddr, daddr, skb->len);
>> -
>> - __skb_push(skb, sizeof(*ip6h));
>> - skb_reset_network_header(skb);
>> - ip6h = ipv6_hdr(skb);
>> - ip6h->version = 6;
>> - ip6h->priority = prio;
>> - ip6h->flow_lbl[0] = 0;
>> - ip6h->flow_lbl[1] = 0;
>> - ip6h->flow_lbl[2] = 0;
>> - ip6h->payload_len = htons(skb->len);
>> - ip6h->nexthdr = IPPROTO_UDP;
>> - ip6h->hop_limit = ttl;
>> - ip6h->daddr = *daddr;
>> - ip6h->saddr = *saddr;
>> -
>> - ip6tunnel_xmit(skb, dev);
>> + udp_tunnel6_xmit_skb(vs->uts.sock, dst, skb, dev, saddr, daddr,
>> prio,
>> + ttl, src_port, dst_port);
>> return 0;
>> }
>> #endif
>> @@ -1663,11 +1619,11 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
>> __be16 src_port, __be16 dst_port, __be32 vni, bool
>> xnet)
>> {
>> struct vxlanhdr *vxh;
>> - struct udphdr *uh;
>> int min_headroom;
>> int err;
>>
>> - skb = vxlan_handle_offloads(skb, !vs->sock->sk->sk_no_check_tx);
>> + skb = udp_tunnel_handle_offloads(skb,
>> +
>> !vs->uts.sock->sk->sk_no_check_tx);
>> if (IS_ERR(skb))
>> return -EINVAL;
>>
>> @@ -1693,20 +1649,8 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
>> vxh->vx_flags = htonl(VXLAN_FLAGS);
>> vxh->vx_vni = vni;
>>
>> - __skb_push(skb, sizeof(*uh));
>> - skb_reset_transport_header(skb);
>> - uh = udp_hdr(skb);
>> -
>> - uh->dest = dst_port;
>> - uh->source = src_port;
>> -
>> - uh->len = htons(skb->len);
>> -
>> - udp_set_csum(vs->sock->sk->sk_no_check_tx, skb,
>> - src, dst, skb->len);
>> -
>> - return iptunnel_xmit(vs->sock->sk, rt, skb, src, dst, IPPROTO_UDP,
>> - tos, ttl, df, xnet);
>> + return udp_tunnel_xmit_skb(vs->uts.sock, rt, skb, src, dst, tos,
>> + ttl, df, src_port, dst_port, xnet);
>> }
>> EXPORT_SYMBOL_GPL(vxlan_xmit_skb);
>>
>> @@ -1831,18 +1775,18 @@ static void vxlan_xmit_one(struct sk_buff *skb,
>> struct net_device *dev,
>> tos = ip_tunnel_ecn_encap(tos, old_iph, skb);
>> ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
>>
>> - err = vxlan_xmit_skb(vxlan->vn_sock, rt, skb,
>> - fl4.saddr, dst->sin.sin_addr.s_addr,
>> - tos, ttl, df, src_port, dst_port,
>> - htonl(vni << 8),
>> - !net_eq(vxlan->net,
>> dev_net(vxlan->dev)));
>> + err = udp_tunnel_xmit_skb(vxlan->vn_sock->uts.sock, rt,
>> skb,
>> + fl4.saddr,
>> dst->sin.sin_addr.s_addr,
>> + tos, ttl, df, src_port,
>> dst_port,
>> + !net_eq(vxlan->net,
>> + dev_net(vxlan->dev)));
>>
>> if (err < 0)
>> goto rt_tx_error;
>> iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
>> #if IS_ENABLED(CONFIG_IPV6)
>> } else {
>> - struct sock *sk = vxlan->vn_sock->sock->sk;
>> + struct sock *sk = vxlan->vn_sock->uts.sock->sk;
>> struct dst_entry *ndst;
>> struct flowi6 fl6;
>> u32 flags;
>> @@ -2204,8 +2148,8 @@ void vxlan_get_rx_port(struct net_device *dev)
>> spin_lock(&vn->sock_lock);
>> for (i = 0; i < PORT_HASH_SIZE; ++i) {
>> hlist_for_each_entry_rcu(vs, &vn->sock_list[i], hlist) {
>> - port = inet_sk(vs->sock->sk)->inet_sport;
>> - sa_family = vs->sock->sk->sk_family;
>> + port = inet_sk(vs->uts.sock->sk)->inet_sport;
>> + sa_family = vs->uts.sock->sk->sk_family;
>> dev->netdev_ops->ndo_add_vxlan_port(dev,
>> sa_family,
>> port);
>> }
>> @@ -2335,79 +2279,60 @@ static const struct ethtool_ops vxlan_ethtool_ops
>> = {
>> static void vxlan_del_work(struct work_struct *work)
>> {
>> struct vxlan_sock *vs = container_of(work, struct vxlan_sock,
>> del_work);
>> -
>> - sk_release_kernel(vs->sock->sk);
>> + udp_tunnel_sock_release(&vs->uts);
>> kfree_rcu(vs, rcu);
>> }
>>
>> -static struct socket *vxlan_create_sock(struct net *net, bool ipv6,
>> - __be16 port, u32 flags)
>> +/* Create new listen socket if needed */
>> +static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16
>> port,
>> + vxlan_rcv_t rcv, void *data,
>> + u32 flags)
>> {
>> - struct socket *sock;
>> - struct udp_port_cfg udp_conf;
>> - int err;
>> + struct vxlan_net *vn = net_generic(net, vxlan_net_id);
>> + struct vxlan_sock *vs;
>> + struct udp_tunnel_socket_cfg vxlan_ts_cfg;
>> + bool ipv6 = !!(flags & VXLAN_F_IPV6);
>> + unsigned int h;
>>
>> - memset(&udp_conf, 0, sizeof(udp_conf));
>> + memset(&vxlan_ts_cfg, 0, sizeof(struct udp_tunnel_socket_cfg));
>>
>> if (ipv6) {
>> - udp_conf.family = AF_INET6;
>> - udp_conf.use_udp6_tx_checksums =
>> + vxlan_ts_cfg.port.family = AF_INET6;
>> + vxlan_ts_cfg.port.use_udp6_tx_checksums =
>> !!(flags & VXLAN_F_UDP_ZERO_CSUM6_TX);
>> - udp_conf.use_udp6_rx_checksums =
>> + vxlan_ts_cfg.port.use_udp6_rx_checksums =
>> !!(flags & VXLAN_F_UDP_ZERO_CSUM6_RX);
>> } else {
>> - udp_conf.family = AF_INET;
>> - udp_conf.local_ip.s_addr = INADDR_ANY;
>> - udp_conf.use_udp_checksums =
>> + vxlan_ts_cfg.port.family = AF_INET;
>> + vxlan_ts_cfg.port.local_ip.s_addr = INADDR_ANY;
>> + vxlan_ts_cfg.port.use_udp_checksums =
>> !!(flags & VXLAN_F_UDP_CSUM);
>> }
>>
>> - udp_conf.local_udp_port = port;
>> + vxlan_ts_cfg.port.local_udp_port = port;
>> + vxlan_ts_cfg.encap_type = 1;
>> + vxlan_ts_cfg.encap_rcv = vxlan_udp_encap_recv;
>> + vxlan_ts_cfg.encap_destroy = NULL;
>>
>> - /* Open UDP socket */
>> - err = udp_sock_create(net, &udp_conf, &sock);
>> - if (err < 0)
>> - return ERR_PTR(err);
>> -
>> - /* Disable multicast loopback */
>> - inet_sk(sock->sk)->mc_loop = 0;
>> -
>> - return sock;
>> -}
>> -
>> -/* Create new listen socket if needed */
>> -static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16
>> port,
>> - vxlan_rcv_t *rcv, void
>> *data,
>> - u32 flags)
>> -{
>> - struct vxlan_net *vn = net_generic(net, vxlan_net_id);
>> - struct vxlan_sock *vs;
>> - struct socket *sock;
>> - struct sock *sk;
>> - unsigned int h;
>> - bool ipv6 = !!(flags & VXLAN_F_IPV6);
>> -
>> - vs = kzalloc(sizeof(*vs), GFP_KERNEL);
>> + vs = (struct vxlan_sock *)create_udp_tunnel_sock(net, sizeof(*vs),
>> + NULL,
>> + &vxlan_ts_cfg);
>> if (!vs)
>> return ERR_PTR(-ENOMEM);
>>
>> for (h = 0; h < VNI_HASH_SIZE; ++h)
>> INIT_HLIST_HEAD(&vs->vni_list[h]);
>>
>> - INIT_WORK(&vs->del_work, vxlan_del_work);
>> + spin_lock(&vn->sock_lock);
>> + list_add(&vs->next, &vn->vxlan_list);
>> + spin_unlock(&vn->sock_lock);
>>
>> - sock = vxlan_create_sock(net, ipv6, port, flags);
>> - if (IS_ERR(sock)) {
>> - kfree(vs);
>> - return ERR_CAST(sock);
>> - }
>> + INIT_WORK(&vs->del_work, vxlan_del_work);
>>
>> - vs->sock = sock;
>> - sk = sock->sk;
>> atomic_set(&vs->refcnt, 1);
>> +
>> vs->rcv = rcv;
>> - vs->data = data;
>> - rcu_assign_sk_user_data(vs->sock->sk, vs);
>> + vs->rcv_data = data;
>>
>> /* Initialize the vxlan udp offloads structure */
>> vs->udp_offloads.port = port;
>> @@ -2419,24 +2344,13 @@ static struct vxlan_sock
>> *vxlan_socket_create(struct net *net, __be16 port,
>> vxlan_notify_add_rx_port(vs);
>> spin_unlock(&vn->sock_lock);
>>
>> - /* Mark socket as an encapsulation socket. */
>> - udp_sk(sk)->encap_type = 1;
>> - udp_sk(sk)->encap_rcv = vxlan_udp_encap_recv;
>> -#if IS_ENABLED(CONFIG_IPV6)
>> - if (ipv6)
>> - ipv6_stub->udpv6_encap_enable();
>> - else
>> -#endif
>> - udp_encap_enable();
>> -
>> return vs;
>> }
>>
>> struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
>> - vxlan_rcv_t *rcv, void *data,
>> + vxlan_rcv_t rcv, void *data,
>> bool no_share, u32 flags)
>> {
>> - struct vxlan_net *vn = net_generic(net, vxlan_net_id);
>> struct vxlan_sock *vs;
>>
>> vs = vxlan_socket_create(net, port, rcv, data, flags);
>> @@ -2446,7 +2360,6 @@ struct vxlan_sock *vxlan_sock_add(struct net *net,
>> __be16 port,
>> if (no_share) /* Return error if sharing is not allowed. */
>> return vs;
>>
>> - spin_lock(&vn->sock_lock);
>> vs = vxlan_find_sock(net, port);
>> if (vs) {
>> if (vs->rcv == rcv)
>> @@ -2454,7 +2367,6 @@ struct vxlan_sock *vxlan_sock_add(struct net *net,
>> __be16 port,
>> else
>> vs = ERR_PTR(-EBUSY);
>> }
>> - spin_unlock(&vn->sock_lock);
>>
>> if (!vs)
>> vs = ERR_PTR(-EINVAL);
>> @@ -2634,7 +2546,6 @@ static int vxlan_newlink(struct net *net, struct
>> net_device *dev,
>> }
>>
>> list_add(&vxlan->next, &vn->vxlan_list);
>> -
>> return 0;
>> }
>>
>> diff --git a/include/net/vxlan.h b/include/net/vxlan.h
>> index d5f59f3..10bfc13 100644
>> --- a/include/net/vxlan.h
>> +++ b/include/net/vxlan.h
>> @@ -4,23 +4,27 @@
>> #include <linux/skbuff.h>
>> #include <linux/netdevice.h>
>> #include <linux/udp.h>
>> +#include <net/udp_tunnel.h>
>>
>> #define VNI_HASH_BITS 10
>> #define VNI_HASH_SIZE (1<<VNI_HASH_BITS)
>>
>> struct vxlan_sock;
>> -typedef void (vxlan_rcv_t)(struct vxlan_sock *vh, struct sk_buff *skb,
>> __be32 key);
>>
>> -/* per UDP socket information */
>> +typedef void (*vxlan_rcv_t)(struct vxlan_sock *vs, struct sk_buff *skb,
>> + __be32 key);
>> +
>> +/* per vxlan socket information */
>> struct vxlan_sock {
>> + struct udp_tunnel_sock uts; /* Must be the first member */
>> struct hlist_node hlist;
>> - vxlan_rcv_t *rcv;
>> - void *data;
>> + struct list_head next;
>> struct work_struct del_work;
>> - struct socket *sock;
>> struct rcu_head rcu;
>> struct hlist_head vni_list[VNI_HASH_SIZE];
>> atomic_t refcnt;
>> + vxlan_rcv_t rcv;
>> + void *rcv_data;
>> struct udp_offload udp_offloads;
>> };
>>
>> @@ -35,7 +39,7 @@ struct vxlan_sock {
>> #define VXLAN_F_UDP_ZERO_CSUM6_RX 0x100
>>
>> struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
>> - vxlan_rcv_t *rcv, void *data,
>> + vxlan_rcv_t rcv, void *data,
>> bool no_share, u32 flags);
>>
>> void vxlan_sock_release(struct vxlan_sock *vs);
>> diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c
>> index d8b7e24..7599efd 100644
>> --- a/net/openvswitch/vport-vxlan.c
>> +++ b/net/openvswitch/vport-vxlan.c
>> @@ -59,7 +59,7 @@ static inline struct vxlan_port *vxlan_vport(const
>> struct vport *vport)
>> static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb, __be32
>> vx_vni)
>> {
>> struct ovs_key_ipv4_tunnel tun_key;
>> - struct vport *vport = vs->data;
>> + struct vport *vport = vs->rcv_data;
>> struct iphdr *iph;
>> __be64 key;
>>
>> @@ -74,7 +74,7 @@ static void vxlan_rcv(struct vxlan_sock *vs, struct
>> sk_buff *skb, __be32 vx_vni)
>> static int vxlan_get_options(const struct vport *vport, struct sk_buff
>> *skb)
>> {
>> struct vxlan_port *vxlan_port = vxlan_vport(vport);
>> - __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
>> + __be16 dst_port =
>> inet_sk(vxlan_port->vs->uts.sock->sk)->inet_sport;
>>
>> if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
>> return -EMSGSIZE;
>> @@ -139,7 +139,7 @@ static int vxlan_tnl_send(struct vport *vport, struct
>> sk_buff *skb)
>> {
>> struct net *net = ovs_dp_get_net(vport->dp);
>> struct vxlan_port *vxlan_port = vxlan_vport(vport);
>> - __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
>> + __be16 dst_port =
>> inet_sk(vxlan_port->vs->uts.sock->sk)->inet_sport;
>> struct rtable *rt;
>> struct flowi4 fl;
>> __be16 src_port;
>> --
>> 1.7.9.5
>>
>> --
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