[patch net-next 0/5] mlxsw: GRE: Offload decap without encap

[patch net-next 0/5] mlxsw: GRE: Offload decap without encap

[Jiri Pirko]

From: Jiri Pirko <jiri@mellanox.com>

Petr says:

The current code doesn't offload GRE decapsulation unless there's a
corresponding encapsulation route as well. While not strictly incorrect (when
encap route is absent, the decap route traps traffic to CPU and the kernel
handles it), it's a missed optimization opportunity.

With this patchset, IPIP entries are created as soon as offloadable tunneling
netdevice is created. This then leads to offloading of decap route, if one
exists, or is added afterwards, even when no encap route is present.

In Linux, when there is a decap route, matching IP-in-IP packets are always
decapsulated. However, with IPv4 overlays in particular, whether the inner
packet is then forwarded depends on setting of net.ipv4.conf.*.rp_filter. When
RP filtering is turned on, inner packets aren't forwarded unless there's a
matching encap route. The mlxsw driver doesn't reflect this behavior in other
router interfaces, and thus it's not implemented for tunnel types either. A
better support for this will be subject of follow-up work.

Petr Machata (5):
  mlxsw: spectrum: Move netdevice NB to struct mlxsw_sp
  mlxsw: spectrum_router: Move mlxsw_sp_netdev_ipip_type()
  mlxsw: spectrum: Support decap-only IP-in-IP tunnels
  mlxsw: spectrum: Support IPIP overlay VRF migration
  mlxsw: spectrum: Drop refcounting of IPIP entries

 drivers/net/ethernet/mellanox/mlxsw/spectrum.c     |  31 ++-
 drivers/net/ethernet/mellanox/mlxsw/spectrum.h     |   8 +
 .../net/ethernet/mellanox/mlxsw/spectrum_ipip.h    |   1 -
 .../net/ethernet/mellanox/mlxsw/spectrum_router.c  | 233 ++++++++++++++++-----
 4 files changed, 209 insertions(+), 64 deletions(-)

-- 
2.9.5

[patch net-next 1/5] mlxsw: spectrum: Move netdevice NB to struct mlxsw_sp

[Jiri Pirko]

From: Petr Machata <petrm@mellanox.com>

So far, all netdevice notifications that the driver cared about were
related to its own ports, and mlxsw_sp could be retrieved from the
netdevice's private data. For IP-in-IP offloading however, the driver
cares about events on foreign netdevices, and getting at mlxsw_sp or
router data structures from the handler is inconvenient.

Therefore move the netdevice notifier blocks from global scope to struct
mlxsw_sp to allow retrieval from the notifier block pointer itself.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum.c | 23 ++++++++++++++++-------
 drivers/net/ethernet/mellanox/mlxsw/spectrum.h |  1 +
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index 321988a..83f9c25 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -3667,6 +3667,9 @@ static int mlxsw_sp_basic_trap_groups_set(struct mlxsw_core *mlxsw_core)
 	return mlxsw_reg_write(mlxsw_core, MLXSW_REG(htgt), htgt_pl);
 }
 
+static int mlxsw_sp_netdevice_event(struct notifier_block *unused,
+				    unsigned long event, void *ptr);
+
 static int mlxsw_sp_init(struct mlxsw_core *mlxsw_core,
 			 const struct mlxsw_bus_info *mlxsw_bus_info)
 {
@@ -3736,6 +3739,16 @@ static int mlxsw_sp_init(struct mlxsw_core *mlxsw_core,
 		goto err_router_init;
 	}
 
+	/* Initialize netdevice notifier after router is initialized, so that
+	 * the event handler can use router structures.
+	 */
+	mlxsw_sp->netdevice_nb.notifier_call = mlxsw_sp_netdevice_event;
+	err = register_netdevice_notifier(&mlxsw_sp->netdevice_nb);
+	if (err) {
+		dev_err(mlxsw_sp->bus_info->dev, "Failed to register netdev notifier\n");
+		goto err_netdev_notifier;
+	}
+
 	err = mlxsw_sp_span_init(mlxsw_sp);
 	if (err) {
 		dev_err(mlxsw_sp->bus_info->dev, "Failed to init span system\n");
@@ -3769,6 +3782,8 @@ static int mlxsw_sp_init(struct mlxsw_core *mlxsw_core,
 err_acl_init:
 	mlxsw_sp_span_fini(mlxsw_sp);
 err_span_init:
+	unregister_netdevice_notifier(&mlxsw_sp->netdevice_nb);
+err_netdev_notifier:
 	mlxsw_sp_router_fini(mlxsw_sp);
 err_router_init:
 	mlxsw_sp_afa_fini(mlxsw_sp);
@@ -3795,6 +3810,7 @@ static void mlxsw_sp_fini(struct mlxsw_core *mlxsw_core)
 	mlxsw_sp_dpipe_fini(mlxsw_sp);
 	mlxsw_sp_acl_fini(mlxsw_sp);
 	mlxsw_sp_span_fini(mlxsw_sp);
+	unregister_netdevice_notifier(&mlxsw_sp->netdevice_nb);
 	mlxsw_sp_router_fini(mlxsw_sp);
 	mlxsw_sp_afa_fini(mlxsw_sp);
 	mlxsw_sp_counter_pool_fini(mlxsw_sp);
@@ -4501,10 +4517,6 @@ static int mlxsw_sp_netdevice_event(struct notifier_block *unused,
 	return notifier_from_errno(err);
 }
 
-static struct notifier_block mlxsw_sp_netdevice_nb __read_mostly = {
-	.notifier_call = mlxsw_sp_netdevice_event,
-};
-
 static struct notifier_block mlxsw_sp_inetaddr_nb __read_mostly = {
 	.notifier_call = mlxsw_sp_inetaddr_event,
 	.priority = 10,	/* Must be called before FIB notifier block */
@@ -4532,7 +4544,6 @@ static int __init mlxsw_sp_module_init(void)
 {
 	int err;
 
-	register_netdevice_notifier(&mlxsw_sp_netdevice_nb);
 	register_inetaddr_notifier(&mlxsw_sp_inetaddr_nb);
 	register_inet6addr_notifier(&mlxsw_sp_inet6addr_nb);
 	register_netevent_notifier(&mlxsw_sp_router_netevent_nb);
@@ -4553,7 +4564,6 @@ static int __init mlxsw_sp_module_init(void)
 	unregister_netevent_notifier(&mlxsw_sp_router_netevent_nb);
 	unregister_inet6addr_notifier(&mlxsw_sp_inet6addr_nb);
 	unregister_inetaddr_notifier(&mlxsw_sp_inetaddr_nb);
-	unregister_netdevice_notifier(&mlxsw_sp_netdevice_nb);
 	return err;
 }
 
@@ -4564,7 +4574,6 @@ static void __exit mlxsw_sp_module_exit(void)
 	unregister_netevent_notifier(&mlxsw_sp_router_netevent_nb);
 	unregister_inet6addr_notifier(&mlxsw_sp_inet6addr_nb);
 	unregister_inetaddr_notifier(&mlxsw_sp_inetaddr_nb);
-	unregister_netdevice_notifier(&mlxsw_sp_netdevice_nb);
 }
 
 module_init(mlxsw_sp_module_init);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index 8e45183..e1a0157 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -161,6 +161,7 @@ struct mlxsw_sp {
 	struct {
 		DECLARE_BITMAP(usage, MLXSW_SP_KVD_LINEAR_SIZE);
 	} kvdl;
+	struct notifier_block netdevice_nb;
 
 	struct mlxsw_sp_counter_pool *counter_pool;
 	struct {
-- 
2.9.5

[patch net-next 2/5] mlxsw: spectrum_router: Move mlxsw_sp_netdev_ipip_type()

[Jiri Pirko]

From: Petr Machata <petrm@mellanox.com>

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
 .../net/ethernet/mellanox/mlxsw/spectrum_router.c  | 38 +++++++++++-----------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index 6a356f4..c5e574b 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -1295,6 +1295,25 @@ mlxsw_sp_ipip_entry_find_by_decap(struct mlxsw_sp *mlxsw_sp,
 	return NULL;
 }
 
+static bool mlxsw_sp_netdev_ipip_type(const struct mlxsw_sp *mlxsw_sp,
+				      const struct net_device *dev,
+				      enum mlxsw_sp_ipip_type *p_type)
+{
+	struct mlxsw_sp_router *router = mlxsw_sp->router;
+	const struct mlxsw_sp_ipip_ops *ipip_ops;
+	enum mlxsw_sp_ipip_type ipipt;
+
+	for (ipipt = 0; ipipt < MLXSW_SP_IPIP_TYPE_MAX; ++ipipt) {
+		ipip_ops = router->ipip_ops_arr[ipipt];
+		if (dev->type == ipip_ops->dev_type) {
+			if (p_type)
+				*p_type = ipipt;
+			return true;
+		}
+	}
+	return false;
+}
+
 struct mlxsw_sp_neigh_key {
 	struct neighbour *n;
 };
@@ -2785,25 +2804,6 @@ static void mlxsw_sp_nexthop_neigh_fini(struct mlxsw_sp *mlxsw_sp,
 	neigh_release(n);
 }
 
-static bool mlxsw_sp_netdev_ipip_type(const struct mlxsw_sp *mlxsw_sp,
-				      const struct net_device *dev,
-				      enum mlxsw_sp_ipip_type *p_type)
-{
-	struct mlxsw_sp_router *router = mlxsw_sp->router;
-	const struct mlxsw_sp_ipip_ops *ipip_ops;
-	enum mlxsw_sp_ipip_type ipipt;
-
-	for (ipipt = 0; ipipt < MLXSW_SP_IPIP_TYPE_MAX; ++ipipt) {
-		ipip_ops = router->ipip_ops_arr[ipipt];
-		if (dev->type == ipip_ops->dev_type) {
-			if (p_type)
-				*p_type = ipipt;
-			return true;
-		}
-	}
-	return false;
-}
-
 static int mlxsw_sp_nexthop_ipip_init(struct mlxsw_sp *mlxsw_sp,
 				      enum mlxsw_sp_ipip_type ipipt,
 				      struct mlxsw_sp_nexthop *nh,
-- 
2.9.5

[patch net-next 3/5] mlxsw: spectrum: Support decap-only IP-in-IP tunnels

[Jiri Pirko]

From: Petr Machata <petrm@mellanox.com>

Current code for offloading IP-in-IP tunneling assumes that there is no
decap without encap. But that's never true for IPv6 overlays, and is not
true for IPv4 ones either, if net.ipv4.conf.*.rp_filter is unset.

To support decap-only tunnels, an IPIP entry is now created as soon as
an offloadable tunneling device is created. When that netdevice is up'd,
a decap route is looked up and possibly offloaded. Thus decap is not
handled implicitly as part of mlxsw_sp_ipip_entry_get() call anymore,
but needs to be done explicitly after the get, if desired.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum.c     |   8 +-
 drivers/net/ethernet/mellanox/mlxsw/spectrum.h     |   6 ++
 .../net/ethernet/mellanox/mlxsw/spectrum_router.c  | 105 +++++++++++++++++++--
 3 files changed, 109 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index 83f9c25..c3ae650 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -4497,13 +4497,17 @@ static bool mlxsw_sp_is_vrf_event(unsigned long event, void *ptr)
 	return netif_is_l3_master(info->upper_dev);
 }
 
-static int mlxsw_sp_netdevice_event(struct notifier_block *unused,
+static int mlxsw_sp_netdevice_event(struct notifier_block *nb,
 				    unsigned long event, void *ptr)
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct mlxsw_sp *mlxsw_sp;
 	int err = 0;
 
-	if (event == NETDEV_CHANGEADDR || event == NETDEV_CHANGEMTU)
+	mlxsw_sp = container_of(nb, struct mlxsw_sp, netdevice_nb);
+	if (mlxsw_sp_netdev_is_ipip(mlxsw_sp, dev))
+		err = mlxsw_sp_netdevice_ipip_event(mlxsw_sp, dev, event);
+	else if (event == NETDEV_CHANGEADDR || event == NETDEV_CHANGEMTU)
 		err = mlxsw_sp_netdevice_router_port_event(dev);
 	else if (mlxsw_sp_is_vrf_event(event, ptr))
 		err = mlxsw_sp_netdevice_vrf_event(dev, event, ptr);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index e1a0157..a4f21af 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -395,6 +395,12 @@ int mlxsw_sp_inet6addr_event(struct notifier_block *unused,
 			     unsigned long event, void *ptr);
 int mlxsw_sp_netdevice_vrf_event(struct net_device *l3_dev, unsigned long event,
 				 struct netdev_notifier_changeupper_info *info);
+bool mlxsw_sp_netdev_is_ipip(const struct mlxsw_sp *mlxsw_sp,
+			     const struct net_device *dev);
+int
+mlxsw_sp_netdevice_ipip_event(struct mlxsw_sp *mlxsw_sp,
+			      struct net_device *l3_dev,
+			      unsigned long event);
 void
 mlxsw_sp_port_vlan_router_leave(struct mlxsw_sp_port_vlan *mlxsw_sp_port_vlan);
 void mlxsw_sp_rif_destroy(struct mlxsw_sp_rif *rif);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index c5e574b..db83422 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -1206,7 +1206,6 @@ mlxsw_sp_ipip_entry_get(struct mlxsw_sp *mlxsw_sp,
 {
 	u32 ul_tb_id = mlxsw_sp_ipip_dev_ul_tb_id(ol_dev);
 	struct mlxsw_sp_router *router = mlxsw_sp->router;
-	struct mlxsw_sp_fib_entry *decap_fib_entry;
 	struct mlxsw_sp_ipip_entry *ipip_entry;
 	enum mlxsw_sp_l3proto ul_proto;
 	union mlxsw_sp_l3addr saddr;
@@ -1231,11 +1230,6 @@ mlxsw_sp_ipip_entry_get(struct mlxsw_sp *mlxsw_sp,
 	if (IS_ERR(ipip_entry))
 		return ipip_entry;
 
-	decap_fib_entry = mlxsw_sp_ipip_entry_find_decap(mlxsw_sp, ipip_entry);
-	if (decap_fib_entry)
-		mlxsw_sp_ipip_entry_promote_decap(mlxsw_sp, ipip_entry,
-						  decap_fib_entry);
-
 	list_add_tail(&ipip_entry->ipip_list_node,
 		      &mlxsw_sp->router->ipip_list);
 
@@ -1250,8 +1244,6 @@ mlxsw_sp_ipip_entry_put(struct mlxsw_sp *mlxsw_sp,
 {
 	if (--ipip_entry->ref_count == 0) {
 		list_del(&ipip_entry->ipip_list_node);
-		if (ipip_entry->decap_fib_entry)
-			mlxsw_sp_ipip_entry_demote_decap(mlxsw_sp, ipip_entry);
 		mlxsw_sp_ipip_entry_destroy(ipip_entry);
 	}
 }
@@ -1314,6 +1306,103 @@ static bool mlxsw_sp_netdev_ipip_type(const struct mlxsw_sp *mlxsw_sp,
 	return false;
 }
 
+bool mlxsw_sp_netdev_is_ipip(const struct mlxsw_sp *mlxsw_sp,
+			     const struct net_device *dev)
+{
+	return mlxsw_sp_netdev_ipip_type(mlxsw_sp, dev, NULL);
+}
+
+static struct mlxsw_sp_ipip_entry *
+mlxsw_sp_ipip_entry_find_by_ol_dev(struct mlxsw_sp *mlxsw_sp,
+				   const struct net_device *ol_dev)
+{
+	struct mlxsw_sp_ipip_entry *ipip_entry;
+
+	list_for_each_entry(ipip_entry, &mlxsw_sp->router->ipip_list,
+			    ipip_list_node)
+		if (ipip_entry->ol_dev == ol_dev)
+			return ipip_entry;
+
+	return NULL;
+}
+
+static int mlxsw_sp_netdevice_ipip_reg_event(struct mlxsw_sp *mlxsw_sp,
+					     struct net_device *ol_dev)
+{
+	struct mlxsw_sp_router *router = mlxsw_sp->router;
+	struct mlxsw_sp_ipip_entry *ipip_entry;
+	enum mlxsw_sp_ipip_type ipipt;
+
+	mlxsw_sp_netdev_ipip_type(mlxsw_sp, ol_dev, &ipipt);
+	if (router->ipip_ops_arr[ipipt]->can_offload(mlxsw_sp, ol_dev,
+						     MLXSW_SP_L3_PROTO_IPV4) ||
+	    router->ipip_ops_arr[ipipt]->can_offload(mlxsw_sp, ol_dev,
+						     MLXSW_SP_L3_PROTO_IPV6)) {
+		ipip_entry = mlxsw_sp_ipip_entry_get(mlxsw_sp, ipipt, ol_dev);
+		if (IS_ERR(ipip_entry))
+			return PTR_ERR(ipip_entry);
+	}
+
+	return 0;
+}
+
+static void mlxsw_sp_netdevice_ipip_unreg_event(struct mlxsw_sp *mlxsw_sp,
+						struct net_device *ol_dev)
+{
+	struct mlxsw_sp_ipip_entry *ipip_entry;
+
+	ipip_entry = mlxsw_sp_ipip_entry_find_by_ol_dev(mlxsw_sp, ol_dev);
+	if (ipip_entry)
+		mlxsw_sp_ipip_entry_put(mlxsw_sp, ipip_entry);
+}
+
+static int mlxsw_sp_netdevice_ipip_up_event(struct mlxsw_sp *mlxsw_sp,
+					    struct net_device *ol_dev)
+{
+	struct mlxsw_sp_fib_entry *decap_fib_entry;
+	struct mlxsw_sp_ipip_entry *ipip_entry;
+
+	ipip_entry = mlxsw_sp_ipip_entry_find_by_ol_dev(mlxsw_sp, ol_dev);
+	if (ipip_entry) {
+		decap_fib_entry = mlxsw_sp_ipip_entry_find_decap(mlxsw_sp,
+								 ipip_entry);
+		if (decap_fib_entry)
+			mlxsw_sp_ipip_entry_promote_decap(mlxsw_sp, ipip_entry,
+							  decap_fib_entry);
+	}
+
+	return 0;
+}
+
+static void mlxsw_sp_netdevice_ipip_down_event(struct mlxsw_sp *mlxsw_sp,
+					       struct net_device *ol_dev)
+{
+	struct mlxsw_sp_ipip_entry *ipip_entry;
+
+	ipip_entry = mlxsw_sp_ipip_entry_find_by_ol_dev(mlxsw_sp, ol_dev);
+	if (ipip_entry && ipip_entry->decap_fib_entry)
+		mlxsw_sp_ipip_entry_demote_decap(mlxsw_sp, ipip_entry);
+}
+
+int mlxsw_sp_netdevice_ipip_event(struct mlxsw_sp *mlxsw_sp,
+				  struct net_device *ol_dev,
+				  unsigned long event)
+{
+	switch (event) {
+	case NETDEV_REGISTER:
+		return mlxsw_sp_netdevice_ipip_reg_event(mlxsw_sp, ol_dev);
+	case NETDEV_UNREGISTER:
+		mlxsw_sp_netdevice_ipip_unreg_event(mlxsw_sp, ol_dev);
+		return 0;
+	case NETDEV_UP:
+		return mlxsw_sp_netdevice_ipip_up_event(mlxsw_sp, ol_dev);
+	case NETDEV_DOWN:
+		mlxsw_sp_netdevice_ipip_down_event(mlxsw_sp, ol_dev);
+		return 0;
+	}
+	return 0;
+}
+
 struct mlxsw_sp_neigh_key {
 	struct neighbour *n;
 };
-- 
2.9.5

[patch net-next 4/5] mlxsw: spectrum: Support IPIP overlay VRF migration

[Jiri Pirko]

From: Petr Machata <petrm@mellanox.com>

IPIP entries are created as soon as an offloadable device is created.
That means that when such a device is later moved to a different VRF,
the loopback device that backs the tunnel is wrong.

Thus when an offloadable encapsulating netdevice moves from one VRF to
another, make sure that the loopback is updated as necessary.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum.c     |  2 +-
 drivers/net/ethernet/mellanox/mlxsw/spectrum.h     |  3 +-
 .../net/ethernet/mellanox/mlxsw/spectrum_router.c  | 47 +++++++++++++++++++++-
 3 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index c3ae650..e1e11c7 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -4506,7 +4506,7 @@ static int mlxsw_sp_netdevice_event(struct notifier_block *nb,
 
 	mlxsw_sp = container_of(nb, struct mlxsw_sp, netdevice_nb);
 	if (mlxsw_sp_netdev_is_ipip(mlxsw_sp, dev))
-		err = mlxsw_sp_netdevice_ipip_event(mlxsw_sp, dev, event);
+		err = mlxsw_sp_netdevice_ipip_event(mlxsw_sp, dev, event, ptr);
 	else if (event == NETDEV_CHANGEADDR || event == NETDEV_CHANGEMTU)
 		err = mlxsw_sp_netdevice_router_port_event(dev);
 	else if (mlxsw_sp_is_vrf_event(event, ptr))
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index a4f21af..28feb74 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -400,7 +400,8 @@ bool mlxsw_sp_netdev_is_ipip(const struct mlxsw_sp *mlxsw_sp,
 int
 mlxsw_sp_netdevice_ipip_event(struct mlxsw_sp *mlxsw_sp,
 			      struct net_device *l3_dev,
-			      unsigned long event);
+			      unsigned long event,
+			      struct netdev_notifier_changeupper_info *info);
 void
 mlxsw_sp_port_vlan_router_leave(struct mlxsw_sp_port_vlan *mlxsw_sp_port_vlan);
 void mlxsw_sp_rif_destroy(struct mlxsw_sp_rif *rif);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index db83422..082cf00 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -1384,9 +1384,49 @@ static void mlxsw_sp_netdevice_ipip_down_event(struct mlxsw_sp *mlxsw_sp,
 		mlxsw_sp_ipip_entry_demote_decap(mlxsw_sp, ipip_entry);
 }
 
+static int mlxsw_sp_netdevice_ipip_vrf_event(struct mlxsw_sp *mlxsw_sp,
+					     struct net_device *ol_dev)
+{
+	struct mlxsw_sp_fib_entry *decap_fib_entry;
+	struct mlxsw_sp_ipip_entry *ipip_entry;
+	struct mlxsw_sp_rif_ipip_lb *lb_rif;
+
+	ipip_entry = mlxsw_sp_ipip_entry_find_by_ol_dev(mlxsw_sp, ol_dev);
+	if (!ipip_entry)
+		return 0;
+
+	/* When a tunneling device is moved to a different VRF, we need to
+	 * update the backing loopback. Since RIFs can't be edited, we need to
+	 * destroy and recreate it. That might create a window of opportunity
+	 * where RALUE and RATR registers end up referencing a RIF that's
+	 * already gone. RATRs are handled by the RIF destroy, and to take care
+	 * of RALUE, demote the decap route back.
+	 */
+	if (ipip_entry->decap_fib_entry)
+		mlxsw_sp_ipip_entry_demote_decap(mlxsw_sp, ipip_entry);
+
+	lb_rif = mlxsw_sp_ipip_ol_ipip_lb_create(mlxsw_sp, ipip_entry->ipipt,
+						 ol_dev);
+	if (IS_ERR(lb_rif))
+		return PTR_ERR(lb_rif);
+	mlxsw_sp_rif_destroy(&ipip_entry->ol_lb->common);
+	ipip_entry->ol_lb = lb_rif;
+
+	if (ol_dev->flags & IFF_UP) {
+		decap_fib_entry = mlxsw_sp_ipip_entry_find_decap(mlxsw_sp,
+								 ipip_entry);
+		if (decap_fib_entry)
+			mlxsw_sp_ipip_entry_promote_decap(mlxsw_sp, ipip_entry,
+							  decap_fib_entry);
+	}
+
+	return 0;
+}
+
 int mlxsw_sp_netdevice_ipip_event(struct mlxsw_sp *mlxsw_sp,
 				  struct net_device *ol_dev,
-				  unsigned long event)
+				  unsigned long event,
+				  struct netdev_notifier_changeupper_info *info)
 {
 	switch (event) {
 	case NETDEV_REGISTER:
@@ -1399,6 +1439,11 @@ int mlxsw_sp_netdevice_ipip_event(struct mlxsw_sp *mlxsw_sp,
 	case NETDEV_DOWN:
 		mlxsw_sp_netdevice_ipip_down_event(mlxsw_sp, ol_dev);
 		return 0;
+	case NETDEV_CHANGEUPPER:
+		if (netif_is_l3_master(info->upper_dev))
+			return mlxsw_sp_netdevice_ipip_vrf_event(mlxsw_sp,
+								 ol_dev);
+		return 0;
 	}
 	return 0;
 }
-- 
2.9.5

[patch net-next 5/5] mlxsw: spectrum: Drop refcounting of IPIP entries

[Jiri Pirko]

From: Petr Machata <petrm@mellanox.com>

Formerly, IPIP entries were created lazily by next hops that referenced
an offloadable IP-in-IP netdevice. However now that they are created
eagerly as a reaction to events on such netdevices, the reference
counting is useless. Hence drop it.

The routes whose next hops reference an offloaded IP-in-IP netdevice
actually linger around a bit after their device is unregistered.
However, mlxsw_sp_ipip_entry_destroy() also destroys the backing
loopback, and mlxsw_sp_rif_destroy() transitively (via
mlxsw_sp_nexthop_rif_gone_sync()) calls mlxsw_sp_nexthop_ipip_fini(),
which unlinks the IPIP entry from a next hop. Thus no dangling pointers
are left behind for the brief window after netdevice is gone, but routes
not yet.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
 .../net/ethernet/mellanox/mlxsw/spectrum_ipip.h    |  1 -
 .../net/ethernet/mellanox/mlxsw/spectrum_router.c  | 49 +++++++++-------------
 2 files changed, 20 insertions(+), 30 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.h
index 1c2db83..6fb4912 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.h
@@ -47,7 +47,6 @@ struct mlxsw_sp_ipip_entry {
 	enum mlxsw_sp_ipip_type ipipt;
 	struct net_device *ol_dev; /* Overlay. */
 	struct mlxsw_sp_rif_ipip_lb *ol_lb;
-	unsigned int ref_count; /* Number of next hops using the tunnel. */
 	struct mlxsw_sp_fib_entry *decap_fib_entry;
 	struct list_head ipip_list_node;
 };
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index 082cf00..3330120 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -1002,9 +1002,8 @@ mlxsw_sp_ipip_entry_alloc(struct mlxsw_sp *mlxsw_sp,
 }
 
 static void
-mlxsw_sp_ipip_entry_destroy(struct mlxsw_sp_ipip_entry *ipip_entry)
+mlxsw_sp_ipip_entry_dealloc(struct mlxsw_sp_ipip_entry *ipip_entry)
 {
-	WARN_ON(ipip_entry->ref_count > 0);
 	mlxsw_sp_rif_destroy(&ipip_entry->ol_lb->common);
 	kfree(ipip_entry);
 }
@@ -1200,9 +1199,9 @@ mlxsw_sp_ipip_entry_find_decap(struct mlxsw_sp *mlxsw_sp,
 }
 
 static struct mlxsw_sp_ipip_entry *
-mlxsw_sp_ipip_entry_get(struct mlxsw_sp *mlxsw_sp,
-			enum mlxsw_sp_ipip_type ipipt,
-			struct net_device *ol_dev)
+mlxsw_sp_ipip_entry_create(struct mlxsw_sp *mlxsw_sp,
+			   enum mlxsw_sp_ipip_type ipipt,
+			   struct net_device *ol_dev)
 {
 	u32 ul_tb_id = mlxsw_sp_ipip_dev_ul_tb_id(ol_dev);
 	struct mlxsw_sp_router *router = mlxsw_sp->router;
@@ -1210,15 +1209,12 @@ mlxsw_sp_ipip_entry_get(struct mlxsw_sp *mlxsw_sp,
 	enum mlxsw_sp_l3proto ul_proto;
 	union mlxsw_sp_l3addr saddr;
 
+	/* The configuration where several tunnels have the same local address
+	 * in the same underlay table needs special treatment in the HW. That is
+	 * currently not implemented in the driver.
+	 */
 	list_for_each_entry(ipip_entry, &mlxsw_sp->router->ipip_list,
 			    ipip_list_node) {
-		if (ipip_entry->ol_dev == ol_dev)
-			goto inc_ref_count;
-
-		/* The configuration where several tunnels have the same local
-		 * address in the same underlay table needs special treatment in
-		 * the HW. That is currently not implemented in the driver.
-		 */
 		ul_proto = router->ipip_ops_arr[ipip_entry->ipipt]->ul_proto;
 		saddr = mlxsw_sp_ipip_netdev_saddr(ul_proto, ol_dev);
 		if (mlxsw_sp_ipip_entry_saddr_matches(mlxsw_sp, ul_proto, saddr,
@@ -1233,19 +1229,15 @@ mlxsw_sp_ipip_entry_get(struct mlxsw_sp *mlxsw_sp,
 	list_add_tail(&ipip_entry->ipip_list_node,
 		      &mlxsw_sp->router->ipip_list);
 
-inc_ref_count:
-	++ipip_entry->ref_count;
 	return ipip_entry;
 }
 
 static void
-mlxsw_sp_ipip_entry_put(struct mlxsw_sp *mlxsw_sp,
-			struct mlxsw_sp_ipip_entry *ipip_entry)
+mlxsw_sp_ipip_entry_destroy(struct mlxsw_sp *mlxsw_sp,
+			    struct mlxsw_sp_ipip_entry *ipip_entry)
 {
-	if (--ipip_entry->ref_count == 0) {
-		list_del(&ipip_entry->ipip_list_node);
-		mlxsw_sp_ipip_entry_destroy(ipip_entry);
-	}
+	list_del(&ipip_entry->ipip_list_node);
+	mlxsw_sp_ipip_entry_dealloc(ipip_entry);
 }
 
 static bool
@@ -1338,7 +1330,8 @@ static int mlxsw_sp_netdevice_ipip_reg_event(struct mlxsw_sp *mlxsw_sp,
 						     MLXSW_SP_L3_PROTO_IPV4) ||
 	    router->ipip_ops_arr[ipipt]->can_offload(mlxsw_sp, ol_dev,
 						     MLXSW_SP_L3_PROTO_IPV6)) {
-		ipip_entry = mlxsw_sp_ipip_entry_get(mlxsw_sp, ipipt, ol_dev);
+		ipip_entry = mlxsw_sp_ipip_entry_create(mlxsw_sp, ipipt,
+							ol_dev);
 		if (IS_ERR(ipip_entry))
 			return PTR_ERR(ipip_entry);
 	}
@@ -1353,7 +1346,7 @@ static void mlxsw_sp_netdevice_ipip_unreg_event(struct mlxsw_sp *mlxsw_sp,
 
 	ipip_entry = mlxsw_sp_ipip_entry_find_by_ol_dev(mlxsw_sp, ol_dev);
 	if (ipip_entry)
-		mlxsw_sp_ipip_entry_put(mlxsw_sp, ipip_entry);
+		mlxsw_sp_ipip_entry_destroy(mlxsw_sp, ipip_entry);
 }
 
 static int mlxsw_sp_netdevice_ipip_up_event(struct mlxsw_sp *mlxsw_sp,
@@ -2939,16 +2932,15 @@ static void mlxsw_sp_nexthop_neigh_fini(struct mlxsw_sp *mlxsw_sp,
 }
 
 static int mlxsw_sp_nexthop_ipip_init(struct mlxsw_sp *mlxsw_sp,
-				      enum mlxsw_sp_ipip_type ipipt,
 				      struct mlxsw_sp_nexthop *nh,
 				      struct net_device *ol_dev)
 {
 	if (!nh->nh_grp->gateway || nh->ipip_entry)
 		return 0;
 
-	nh->ipip_entry = mlxsw_sp_ipip_entry_get(mlxsw_sp, ipipt, ol_dev);
-	if (IS_ERR(nh->ipip_entry))
-		return PTR_ERR(nh->ipip_entry);
+	nh->ipip_entry = mlxsw_sp_ipip_entry_find_by_ol_dev(mlxsw_sp, ol_dev);
+	if (!nh->ipip_entry)
+		return -ENOENT;
 
 	__mlxsw_sp_nexthop_neigh_update(nh, false);
 	return 0;
@@ -2963,7 +2955,6 @@ static void mlxsw_sp_nexthop_ipip_fini(struct mlxsw_sp *mlxsw_sp,
 		return;
 
 	__mlxsw_sp_nexthop_neigh_update(nh, true);
-	mlxsw_sp_ipip_entry_put(mlxsw_sp, ipip_entry);
 	nh->ipip_entry = NULL;
 }
 
@@ -3007,7 +2998,7 @@ static int mlxsw_sp_nexthop4_type_init(struct mlxsw_sp *mlxsw_sp,
 	    router->ipip_ops_arr[ipipt]->can_offload(mlxsw_sp, dev,
 						     MLXSW_SP_L3_PROTO_IPV4)) {
 		nh->type = MLXSW_SP_NEXTHOP_TYPE_IPIP;
-		err = mlxsw_sp_nexthop_ipip_init(mlxsw_sp, ipipt, nh, dev);
+		err = mlxsw_sp_nexthop_ipip_init(mlxsw_sp, nh, dev);
 		if (err)
 			return err;
 		mlxsw_sp_nexthop_rif_init(nh, &nh->ipip_entry->ol_lb->common);
@@ -4269,7 +4260,7 @@ static int mlxsw_sp_nexthop6_type_init(struct mlxsw_sp *mlxsw_sp,
 	    router->ipip_ops_arr[ipipt]->can_offload(mlxsw_sp, dev,
 						     MLXSW_SP_L3_PROTO_IPV6)) {
 		nh->type = MLXSW_SP_NEXTHOP_TYPE_IPIP;
-		err = mlxsw_sp_nexthop_ipip_init(mlxsw_sp, ipipt, nh, dev);
+		err = mlxsw_sp_nexthop_ipip_init(mlxsw_sp, nh, dev);
 		if (err)
 			return err;
 		mlxsw_sp_nexthop_rif_init(nh, &nh->ipip_entry->ol_lb->common);
-- 
2.9.5

[patch net-next 0/5] mlxsw: GRE: Offload decap without encap

[Jiri Pirko]

From: Jiri Pirko <jiri@mellanox.com>

Petr says:

The current code doesn't offload GRE decapsulation unless there's a
corresponding encapsulation route as well. While not strictly incorrect (when
encap route is absent, the decap route traps traffic to CPU and the kernel
handles it), it's a missed optimization opportunity.

With this patchset, IPIP entries are created as soon as offloadable tunneling
netdevice is created. This then leads to offloading of decap route, if one
exists, or is added afterwards, even when no encap route is present.

In Linux, when there is a decap route, matching IP-in-IP packets are always
decapsulated. However, with IPv4 overlays in particular, whether the inner
packet is then forwarded depends on setting of net.ipv4.conf.*.rp_filter. When
RP filtering is turned on, inner packets aren't forwarded unless there's a
matching encap route. The mlxsw driver doesn't reflect this behavior in other
router interfaces, and thus it's not implemented for tunnel types either. A
better support for this will be subject of follow-up work.

Petr Machata (5):
  mlxsw: spectrum: Move netdevice NB to struct mlxsw_sp
  mlxsw: spectrum_router: Move mlxsw_sp_netdev_ipip_type()
  mlxsw: spectrum: Support decap-only IP-in-IP tunnels
  mlxsw: spectrum: Support IPIP overlay VRF migration
  mlxsw: spectrum: Drop refcounting of IPIP entries

 drivers/net/ethernet/mellanox/mlxsw/spectrum.c     |  31 ++-
 drivers/net/ethernet/mellanox/mlxsw/spectrum.h     |   8 +
 .../net/ethernet/mellanox/mlxsw/spectrum_ipip.h    |   1 -
 .../net/ethernet/mellanox/mlxsw/spectrum_router.c  | 233 ++++++++++++++++-----
 4 files changed, 209 insertions(+), 64 deletions(-)

-- 
2.9.5

Re: [patch net-next 0/5] mlxsw: GRE: Offload decap without encap

[Jiri Pirko]

Please ignore this thread. I did not clean the format-patch dir :/

Re: [patch net-next 0/5] mlxsw: GRE: Offload decap without encap

[David Miller]

From: Jiri Pirko <jiri@resnulli.us>
Date: Mon, 16 Oct 2017 16:26:34 +0200

> From: Jiri Pirko <jiri@mellanox.com>
> 
> Petr says:
> 
> The current code doesn't offload GRE decapsulation unless there's a
> corresponding encapsulation route as well. While not strictly incorrect (when
> encap route is absent, the decap route traps traffic to CPU and the kernel
> handles it), it's a missed optimization opportunity.
> 
> With this patchset, IPIP entries are created as soon as offloadable tunneling
> netdevice is created. This then leads to offloading of decap route, if one
> exists, or is added afterwards, even when no encap route is present.
> 
> In Linux, when there is a decap route, matching IP-in-IP packets are always
> decapsulated. However, with IPv4 overlays in particular, whether the inner
> packet is then forwarded depends on setting of net.ipv4.conf.*.rp_filter. When
> RP filtering is turned on, inner packets aren't forwarded unless there's a
> matching encap route. The mlxsw driver doesn't reflect this behavior in other
> router interfaces, and thus it's not implemented for tunnel types either. A
> better support for this will be subject of follow-up work.

Series applied.