From: Paul Blakey <paulb@mellanox.com>
Date: Wed, 4 Sep 2019 16:56:37 +0300
Subject: net: openvswitch: Set OvS recirc_id from tc chain index
Patch-mainline: v5.4-rc1
Git-commit: 95a7233c452a58a4c2310c456c73997853b2ec46
References: jsc#SLE-15172
Offloaded OvS datapath rules are translated one to one to tc rules,
for example the following simplified OvS rule:
recirc_id(0),in_port(dev1),eth_type(0x0800),ct_state(-trk) actions:ct(),recirc(2)
Will be translated to the following tc rule:
$ tc filter add dev dev1 ingress \
prio 1 chain 0 proto ip \
flower tcp ct_state -trk \
action ct pipe \
action goto chain 2
Received packets will first travel though tc, and if they aren't stolen
by it, like in the above rule, they will continue to OvS datapath.
Since we already did some actions (action ct in this case) which might
modify the packets, and updated action stats, we would like to continue
the proccessing with the correct recirc_id in OvS (here recirc_id(2))
where we left off.
To support this, introduce a new skb extension for tc, which
will be used for translating tc chain to ovs recirc_id to
handle these miss cases. Last tc chain index will be set
by tc goto chain action and read by OvS datapath.
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/linux/skbuff.h | 13 +++++++++++++
include/uapi/linux/openvswitch.h | 3 +++
net/core/skbuff.c | 6 ++++++
net/openvswitch/datapath.c | 38 +++++++++++++++++++++++++++++++++-----
net/openvswitch/datapath.h | 2 ++
net/openvswitch/flow.c | 13 +++++++++++++
net/sched/Kconfig | 13 +++++++++++++
net/sched/cls_api.c | 12 ++++++++++++
8 files changed, 95 insertions(+), 5 deletions(-)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -279,6 +279,16 @@ struct nf_bridge_info {
};
#endif
+#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+/* Chain in tc_skb_ext will be used to share the tc chain with
+ * ovs recirc_id. It will be set to the current chain by tc
+ * and read by ovs to recirc_id.
+ */
+struct tc_skb_ext {
+ __u32 chain;
+};
+#endif
+
struct sk_buff_head {
/* These two members must be first. */
struct sk_buff *next;
@@ -4058,6 +4068,9 @@ enum skb_ext_id {
#ifdef CONFIG_XFRM
SKB_EXT_SEC_PATH,
#endif
+#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+ TC_SKB_EXT,
+#endif
SKB_EXT_NUM, /* must be last */
};
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -123,6 +123,9 @@ struct ovs_vport_stats {
/* Allow datapath to associate multiple Netlink PIDs to each vport */
#define OVS_DP_F_VPORT_PIDS (1 << 1)
+/* Allow tc offload recirc sharing */
+#define OVS_DP_F_TC_RECIRC_SHARING (1 << 2)
+
/* Fixed logical ports. */
#define OVSP_LOCAL ((__u32)0)
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -4106,6 +4106,9 @@ static const u8 skb_ext_type_len[] = {
#ifdef CONFIG_XFRM
[SKB_EXT_SEC_PATH] = SKB_EXT_CHUNKSIZEOF(struct sec_path),
#endif
+#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+ [TC_SKB_EXT] = SKB_EXT_CHUNKSIZEOF(struct tc_skb_ext),
+#endif
};
static __always_inline unsigned int skb_ext_total_length(void)
@@ -4117,6 +4120,9 @@ static __always_inline unsigned int skb_
#ifdef CONFIG_XFRM
skb_ext_type_len[SKB_EXT_SEC_PATH] +
#endif
+#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+ skb_ext_type_len[TC_SKB_EXT] +
+#endif
0;
}
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -1542,10 +1542,34 @@ static void ovs_dp_reset_user_features(s
dp->user_features = 0;
}
-static void ovs_dp_change(struct datapath *dp, struct nlattr *a[])
+DEFINE_STATIC_KEY_FALSE(tc_recirc_sharing_support);
+
+static int ovs_dp_change(struct datapath *dp, struct nlattr *a[])
{
- if (a[OVS_DP_ATTR_USER_FEATURES])
- dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
+ u32 user_features = 0;
+
+ if (a[OVS_DP_ATTR_USER_FEATURES]) {
+ user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
+
+ if (user_features & ~(OVS_DP_F_VPORT_PIDS |
+ OVS_DP_F_UNALIGNED |
+ OVS_DP_F_TC_RECIRC_SHARING))
+ return -EOPNOTSUPP;
+
+#if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+ if (user_features & OVS_DP_F_TC_RECIRC_SHARING)
+ return -EOPNOTSUPP;
+#endif
+ }
+
+ dp->user_features = user_features;
+
+ if (dp->user_features & OVS_DP_F_TC_RECIRC_SHARING)
+ static_branch_enable(&tc_recirc_sharing_support);
+ else
+ static_branch_disable(&tc_recirc_sharing_support);
+
+ return 0;
}
static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
@@ -1607,7 +1631,9 @@ static int ovs_dp_cmd_new(struct sk_buff
parms.port_no = OVSP_LOCAL;
parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
- ovs_dp_change(dp, a);
+ err = ovs_dp_change(dp, a);
+ if (err)
+ goto err_destroy_meters;
/* So far only local changes have been made, now need the lock. */
ovs_lock();
@@ -1733,7 +1759,9 @@ static int ovs_dp_cmd_set(struct sk_buff
if (IS_ERR(dp))
goto err_unlock_free;
- ovs_dp_change(dp, info->attrs);
+ err = ovs_dp_change(dp, info->attrs);
+ if (err)
+ goto err_unlock_free;
err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
info->snd_seq, 0, OVS_DP_CMD_SET);
--- a/net/openvswitch/datapath.h
+++ b/net/openvswitch/datapath.h
@@ -218,6 +218,8 @@ static inline struct datapath *get_dp(st
extern struct notifier_block ovs_dp_device_notifier;
extern struct genl_family dp_vport_genl_family;
+DECLARE_STATIC_KEY_FALSE(tc_recirc_sharing_support);
+
void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key);
void ovs_dp_detach_port(struct vport *);
int ovs_dp_upcall(struct datapath *, struct sk_buff *,
--- a/net/openvswitch/flow.c
+++ b/net/openvswitch/flow.c
@@ -842,6 +842,9 @@ static int key_extract_mac_proto(struct
int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
struct sk_buff *skb, struct sw_flow_key *key)
{
+#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+ struct tc_skb_ext *tc_ext;
+#endif
int res, err;
/* Extract metadata from packet. */
@@ -874,7 +877,17 @@ int ovs_flow_key_extract(const struct ip
if (res < 0)
return res;
key->mac_proto = res;
+
+#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+ if (static_branch_unlikely(&tc_recirc_sharing_support)) {
+ tc_ext = skb_ext_find(skb, TC_SKB_EXT);
+ key->recirc_id = tc_ext ? tc_ext->chain : 0;
+ } else {
+ key->recirc_id = 0;
+ }
+#else
key->recirc_id = 0;
+#endif
err = key_extract(skb, key);
if (!err)
--- a/net/sched/Kconfig
+++ b/net/sched/Kconfig
@@ -963,6 +963,19 @@ config NET_IFE_SKBTCINDEX
tristate "Support to encoding decoding skb tcindex on IFE action"
depends on NET_ACT_IFE
+config NET_TC_SKB_EXT
+ bool "TC recirculation support"
+ depends on NET_CLS_ACT
+ default y if NET_CLS_ACT
+ select SKB_EXTENSIONS
+
+ help
+ Say Y here to allow tc chain misses to continue in OvS datapath in
+ the correct recirc_id, and hardware chain misses to continue in
+ the correct chain in tc software datapath.
+
+ Say N here if you won't be using tc<->ovs offload or tc chains offload.
+
endif # NET_SCHED
config NET_SCH_FIFO
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -1514,6 +1514,18 @@ reclassify:
goto reset;
} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
first_tp = res->goto_tp;
+
+#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
+ {
+ struct tc_skb_ext *ext;
+
+ ext = skb_ext_add(skb, TC_SKB_EXT);
+ if (WARN_ON_ONCE(!ext))
+ return TC_ACT_SHOT;
+
+ ext->chain = err & TC_ACT_EXT_VAL_MASK;
+ }
+#endif
goto reset;
}
#endif