Merge branch 'mlxsw-Handle-changes-in-GRE-configuration'

Jiri Pirko says:

====================
mlxsw: Handle changes in GRE configuration

Petr says:

Until now, when an IP tunnel was offloaded by the mlxsw driver, the
offload was pretty much static, and changes in Linux configuration were
not reflected in the hardware. That led to discrepancies between traffic
flows in slow path and fast path. The work-around used to be to remove
all routes that forward to the netdevice and re-add them. This is
clearly suboptimal, but actually, as of the decap-only patchset, it's
not even enough anymore, and one needs to go all the way and simply drop
the tunnel and recreate it correctly.

With this patchset, the NETDEV_CHANGE events that are generated for
changes of up'd tunnel netdevices are captured and interpreted to
correctly reconfigure the HW in accordance with changes requested at the
software layer. In addition, NETDEV_CHANGEUPPER, NETDEV_UP and
NETDEV_DOWN are now handled not only for tunnel devices themselves, but
also for their bound devices. Each change is then translated to one or
more of the following updates to the HW configuration:

- refresh of offload of local route that corresponds to tunnel's local
  address
- refresh of the loopback RIF
- refresh of offloads of routes that forward to the changed tunnel
- removal of tunnel offloads

These tools are used to implement the following configuration changes:

- addition of a new offloadable tunnel with local address that conflicts
  with that of an already-offloaded tunnel (the existing tunnel is
  onloaded, the new one isn't offloaded)
- changes to TTL, TOS that make tunnel unsuitable for offloading
- changes to ikey, okey, remote
- changes to local, which when they cause conflict with another
  tunnel, lead to onloading of both newly-conflicting tunnels
- migration of a bound device of an offloaded tunnel device to a
  different VRF
- changes to what device is bound to a tunnel device (i.e. like what
  "ip tunnel change name g dev another" does)
- changes to up / down state of a bound device. A down bound device
  doesn't forward encapsulated traffic anymore, but decap still works.

This patchset starts with a suite of patches that adapt the existing
code base step by step to facilitate introduction of the offloading
code. The five substantial patches at the end then implement the changes
mentioned above.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 169 insertions, 14 deletions

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c
index 702fe945227c..7502e53447bd 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c
@@ -36,36 +36,123 @@
 
 #include "spectrum_ipip.h"
 
-static bool
-mlxsw_sp_ipip_netdev_has_ikey(const struct net_device *ol_dev)
+struct ip_tunnel_parm
+mlxsw_sp_ipip_netdev_parms(const struct net_device *ol_dev)
 {
 	struct ip_tunnel *tun = netdev_priv(ol_dev);
 
-	return !!(tun->parms.i_flags & TUNNEL_KEY);
+	return tun->parms;
 }
 
-static bool
-mlxsw_sp_ipip_netdev_has_okey(const struct net_device *ol_dev)
+static bool mlxsw_sp_ipip_parms_has_ikey(struct ip_tunnel_parm parms)
 {
-	struct ip_tunnel *tun = netdev_priv(ol_dev);
+	return !!(parms.i_flags & TUNNEL_KEY);
+}
 
-	return !!(tun->parms.o_flags & TUNNEL_KEY);
+static bool mlxsw_sp_ipip_parms_has_okey(struct ip_tunnel_parm parms)
+{
+	return !!(parms.o_flags & TUNNEL_KEY);
 }
 
-static u32 mlxsw_sp_ipip_netdev_ikey(const struct net_device *ol_dev)
+static u32 mlxsw_sp_ipip_parms_ikey(struct ip_tunnel_parm parms)
 {
-	struct ip_tunnel *tun = netdev_priv(ol_dev);
+	return mlxsw_sp_ipip_parms_has_ikey(parms) ?
+		be32_to_cpu(parms.i_key) : 0;
+}
+
+static u32 mlxsw_sp_ipip_parms_okey(struct ip_tunnel_parm parms)
+{
+	return mlxsw_sp_ipip_parms_has_okey(parms) ?
+		be32_to_cpu(parms.o_key) : 0;
+}
 
-	return mlxsw_sp_ipip_netdev_has_ikey(ol_dev) ?
-		be32_to_cpu(tun->parms.i_key) : 0;
+static __be32 mlxsw_sp_ipip_parms_saddr4(struct ip_tunnel_parm parms)
+{
+	return parms.iph.saddr;
+}
+
+static union mlxsw_sp_l3addr
+mlxsw_sp_ipip_parms_saddr(enum mlxsw_sp_l3proto proto,
+			  struct ip_tunnel_parm parms)
+{
+	switch (proto) {
+	case MLXSW_SP_L3_PROTO_IPV4:
+		return (union mlxsw_sp_l3addr) {
+			.addr4 = mlxsw_sp_ipip_parms_saddr4(parms),
+		};
+	case MLXSW_SP_L3_PROTO_IPV6:
+		break;
+	}
+
+	WARN_ON(1);
+	return (union mlxsw_sp_l3addr) {
+		.addr4 = 0,
+	};
+}
+
+static __be32 mlxsw_sp_ipip_parms_daddr4(struct ip_tunnel_parm parms)
+{
+	return parms.iph.daddr;
+}
+
+static union mlxsw_sp_l3addr
+mlxsw_sp_ipip_parms_daddr(enum mlxsw_sp_l3proto proto,
+			  struct ip_tunnel_parm parms)
+{
+	switch (proto) {
+	case MLXSW_SP_L3_PROTO_IPV4:
+		return (union mlxsw_sp_l3addr) {
+			.addr4 = mlxsw_sp_ipip_parms_daddr4(parms),
+		};
+	case MLXSW_SP_L3_PROTO_IPV6:
+		break;
+	}
+
+	WARN_ON(1);
+	return (union mlxsw_sp_l3addr) {
+		.addr4 = 0,
+	};
+}
+
+static bool mlxsw_sp_ipip_netdev_has_ikey(const struct net_device *ol_dev)
+{
+	return mlxsw_sp_ipip_parms_has_ikey(mlxsw_sp_ipip_netdev_parms(ol_dev));
+}
+
+static bool mlxsw_sp_ipip_netdev_has_okey(const struct net_device *ol_dev)
+{
+	return mlxsw_sp_ipip_parms_has_okey(mlxsw_sp_ipip_netdev_parms(ol_dev));
+}
+
+static u32 mlxsw_sp_ipip_netdev_ikey(const struct net_device *ol_dev)
+{
+	return mlxsw_sp_ipip_parms_ikey(mlxsw_sp_ipip_netdev_parms(ol_dev));
 }
 
 static u32 mlxsw_sp_ipip_netdev_okey(const struct net_device *ol_dev)
 {
-	struct ip_tunnel *tun = netdev_priv(ol_dev);
+	return mlxsw_sp_ipip_parms_okey(mlxsw_sp_ipip_netdev_parms(ol_dev));
+}
+
+union mlxsw_sp_l3addr
+mlxsw_sp_ipip_netdev_saddr(enum mlxsw_sp_l3proto proto,
+			   const struct net_device *ol_dev)
+{
+	return mlxsw_sp_ipip_parms_saddr(proto,
+					 mlxsw_sp_ipip_netdev_parms(ol_dev));
+}
+
+static __be32 mlxsw_sp_ipip_netdev_daddr4(const struct net_device *ol_dev)
+{
+	return mlxsw_sp_ipip_parms_daddr4(mlxsw_sp_ipip_netdev_parms(ol_dev));
+}
 
-	return mlxsw_sp_ipip_netdev_has_okey(ol_dev) ?
-		be32_to_cpu(tun->parms.o_key) : 0;
+static union mlxsw_sp_l3addr
+mlxsw_sp_ipip_netdev_daddr(enum mlxsw_sp_l3proto proto,
+			   const struct net_device *ol_dev)
+{
+	return mlxsw_sp_ipip_parms_daddr(proto,
+					 mlxsw_sp_ipip_netdev_parms(ol_dev));
 }
 
 static int
@@ -200,6 +287,73 @@ mlxsw_sp_ipip_ol_loopback_config_gre4(struct mlxsw_sp *mlxsw_sp,
 	};
 }
 
+static int
+mlxsw_sp_ipip_ol_netdev_change_gre4(struct mlxsw_sp *mlxsw_sp,
+				    struct mlxsw_sp_ipip_entry *ipip_entry,
+				    struct netlink_ext_ack *extack)
+{
+	union mlxsw_sp_l3addr old_saddr, new_saddr;
+	union mlxsw_sp_l3addr old_daddr, new_daddr;
+	struct ip_tunnel_parm new_parms;
+	bool update_tunnel = false;
+	bool update_decap = false;
+	bool update_nhs = false;
+	int err = 0;
+
+	new_parms = mlxsw_sp_ipip_netdev_parms(ipip_entry->ol_dev);
+
+	new_saddr = mlxsw_sp_ipip_parms_saddr(MLXSW_SP_L3_PROTO_IPV4,
+					      new_parms);
+	old_saddr = mlxsw_sp_ipip_parms_saddr(MLXSW_SP_L3_PROTO_IPV4,
+					      ipip_entry->parms);
+	new_daddr = mlxsw_sp_ipip_parms_daddr(MLXSW_SP_L3_PROTO_IPV4,
+					      new_parms);
+	old_daddr = mlxsw_sp_ipip_parms_daddr(MLXSW_SP_L3_PROTO_IPV4,
+					      ipip_entry->parms);
+
+	if (!mlxsw_sp_l3addr_eq(&new_saddr, &old_saddr)) {
+		u16 ul_tb_id = mlxsw_sp_ipip_dev_ul_tb_id(ipip_entry->ol_dev);
+
+		/* Since the local address has changed, if there is another
+		 * tunnel with a matching saddr, both need to be demoted.
+		 */
+		if (mlxsw_sp_ipip_demote_tunnel_by_saddr(mlxsw_sp,
+							 MLXSW_SP_L3_PROTO_IPV4,
+							 new_saddr, ul_tb_id,
+							 ipip_entry)) {
+			mlxsw_sp_ipip_entry_demote_tunnel(mlxsw_sp, ipip_entry);
+			return 0;
+		}
+
+		update_tunnel = true;
+	} else if ((mlxsw_sp_ipip_parms_okey(ipip_entry->parms) !=
+		    mlxsw_sp_ipip_parms_okey(new_parms)) ||
+		   ipip_entry->parms.link != new_parms.link) {
+		update_tunnel = true;
+	} else if (!mlxsw_sp_l3addr_eq(&new_daddr, &old_daddr)) {
+		update_nhs = true;
+	} else if (mlxsw_sp_ipip_parms_ikey(ipip_entry->parms) !=
+		   mlxsw_sp_ipip_parms_ikey(new_parms)) {
+		update_decap = true;
+	}
+
+	if (update_tunnel)
+		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
+							  true, true, true,
+							  extack);
+	else if (update_nhs)
+		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
+							  false, false, true,
+							  extack);
+	else if (update_decap)
+		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
+							  false, false, false,
+							  extack);
+
+	ipip_entry->parms = new_parms;
+	return err;
+}
+
 static const struct mlxsw_sp_ipip_ops mlxsw_sp_ipip_gre4_ops = {
 	.dev_type = ARPHRD_IPGRE,
 	.ul_proto = MLXSW_SP_L3_PROTO_IPV4,
@@ -207,6 +361,7 @@ static const struct mlxsw_sp_ipip_ops mlxsw_sp_ipip_gre4_ops = {
 	.fib_entry_op = mlxsw_sp_ipip_fib_entry_op_gre4,
 	.can_offload = mlxsw_sp_ipip_can_offload_gre4,
 	.ol_loopback_config = mlxsw_sp_ipip_ol_loopback_config_gre4,
+	.ol_netdev_change = mlxsw_sp_ipip_ol_netdev_change_gre4,
 };
 
 const struct mlxsw_sp_ipip_ops *mlxsw_sp_ipip_ops_arr[] = {