mlxsw: spectrum: Add the multicast routing offloading logic

Add the multicast router offloading logic, which is in charge of handling
the VIF and MFC notifications and translating it to the hardware logic API.

The offloading logic has to overcome several obstacles in order to safely
comply with the kernel multicast router user API:
 - It must keep track of the mapping between VIFs to netdevices. The user
   can add an MFC cache entry pointing to a VIF, delete the VIF and add
   re-add it with a different netdevice. The offloading logic has to handle
   this in order to be compatible with the kernel logic.
 - It must keep track of the mapping between netdevices to spectrum RIFs,
   as the current hardware implementation assume having a RIF for every
   port in a multicast router.
 - It must handle routes pointing to pimreg device to be trapped to the
   kernel, as the packet should be delivered to userspace.
 - It must handle routes pointing tunnel VIFs. The current implementation
   does not support multicast forwarding to tunnels, thus routes that point
   to a tunnel should be trapped to the kernel.
 - It must be aware of proxy multicast routes, which include both (*,*)
   routes and duplicate routes. Currently proxy routes are not offloaded
   and trigger the abort mechanism: removal of all routes from hardware and
   triggering the traffic to go through the kernel.

The multicast routing offloading logic also updates the counters of the
offloaded MFC routes in a periodic work.

Signed-off-by: Yotam Gigi <yotamg@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/Makefile

@@ -17,7 +17,8 @@ mlxsw_spectrum-objs		:= spectrum.o spectrum_buffers.o \
 				   spectrum_kvdl.o spectrum_acl_tcam.o \
 				   spectrum_acl.o spectrum_flower.o \
 				   spectrum_cnt.o spectrum_fid.o \
-				   spectrum_ipip.o spectrum_acl_flex_actions.o
+				   spectrum_ipip.o spectrum_acl_flex_actions.o \
+				   spectrum_mr.o
 mlxsw_spectrum-$(CONFIG_MLXSW_SPECTRUM_DCB)	+= spectrum_dcb.o
 mlxsw_spectrum-$(CONFIG_NET_DEVLINK) += spectrum_dpipe.o
 obj-$(CONFIG_MLXSW_MINIMAL)	+= mlxsw_minimal.o

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

@@ -153,6 +153,7 @@ struct mlxsw_sp {
 	struct mlxsw_sp_sb *sb;
 	struct mlxsw_sp_bridge *bridge;
 	struct mlxsw_sp_router *router;
+	struct mlxsw_sp_mr *mr;
 	struct mlxsw_afa *afa;
 	struct mlxsw_sp_acl *acl;
 	struct mlxsw_sp_fid_core *fid_core;

drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.h

@@ -0,0 +1,133 @@
+/*
+ * drivers/net/ethernet/mellanox/mlxsw/spectrum_mr.h
+ * Copyright (c) 2017 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2017 Yotam Gigi <yotamg@mellanox.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _MLXSW_SPECTRUM_MCROUTER_H
+#define _MLXSW_SPECTRUM_MCROUTER_H
+
+#include <linux/mroute.h>
+#include "spectrum_router.h"
+#include "spectrum.h"
+
+enum mlxsw_sp_mr_route_action {
+	MLXSW_SP_MR_ROUTE_ACTION_FORWARD,
+	MLXSW_SP_MR_ROUTE_ACTION_TRAP,
+};
+
+enum mlxsw_sp_mr_route_prio {
+	MLXSW_SP_MR_ROUTE_PRIO_SG,
+	MLXSW_SP_MR_ROUTE_PRIO_STARG,
+	MLXSW_SP_MR_ROUTE_PRIO_CATCHALL,
+	__MLXSW_SP_MR_ROUTE_PRIO_MAX
+};
+
+#define MLXSW_SP_MR_ROUTE_PRIO_MAX (__MLXSW_SP_MR_ROUTE_PRIO_MAX - 1)
+
+struct mlxsw_sp_mr_route_key {
+	int vrid;
+	enum mlxsw_sp_l3proto proto;
+	union mlxsw_sp_l3addr group;
+	union mlxsw_sp_l3addr group_mask;
+	union mlxsw_sp_l3addr source;
+	union mlxsw_sp_l3addr source_mask;
+};
+
+struct mlxsw_sp_mr_route_info {
+	enum mlxsw_sp_mr_route_action route_action;
+	u16 irif_index;
+	u16 *erif_indices;
+	size_t erif_num;
+	u16 min_mtu;
+};
+
+struct mlxsw_sp_mr_route_params {
+	struct mlxsw_sp_mr_route_key key;
+	struct mlxsw_sp_mr_route_info value;
+	enum mlxsw_sp_mr_route_prio prio;
+};
+
+struct mlxsw_sp_mr_ops {
+	int priv_size;
+	int route_priv_size;
+	int (*init)(struct mlxsw_sp *mlxsw_sp, void *priv);
+	int (*route_create)(struct mlxsw_sp *mlxsw_sp, void *priv,
+			    void *route_priv,
+			    struct mlxsw_sp_mr_route_params *route_params);
+	int (*route_update)(struct mlxsw_sp *mlxsw_sp, void *route_priv,
+			    struct mlxsw_sp_mr_route_info *route_info);
+	int (*route_stats)(struct mlxsw_sp *mlxsw_sp, void *route_priv,
+			   u64 *packets, u64 *bytes);
+	int (*route_action_update)(struct mlxsw_sp *mlxsw_sp, void *route_priv,
+				   enum mlxsw_sp_mr_route_action route_action);
+	int (*route_min_mtu_update)(struct mlxsw_sp *mlxsw_sp, void *route_priv,
+				    u16 min_mtu);
+	int (*route_irif_update)(struct mlxsw_sp *mlxsw_sp, void *route_priv,
+				 u16 irif_index);
+	int (*route_erif_add)(struct mlxsw_sp *mlxsw_sp, void *route_priv,
+			      u16 erif_index);
+	int (*route_erif_del)(struct mlxsw_sp *mlxsw_sp, void *route_priv,
+			      u16 erif_index);
+	void (*route_destroy)(struct mlxsw_sp *mlxsw_sp, void *priv,
+			      void *route_priv);
+	void (*fini)(void *priv);
+};
+
+struct mlxsw_sp_mr;
+struct mlxsw_sp_mr_table;
+
+int mlxsw_sp_mr_init(struct mlxsw_sp *mlxsw_sp,
+		     const struct mlxsw_sp_mr_ops *mr_ops);
+void mlxsw_sp_mr_fini(struct mlxsw_sp *mlxsw_sp);
+int mlxsw_sp_mr_route4_add(struct mlxsw_sp_mr_table *mr_table,
+			   struct mfc_cache *mfc, bool replace);
+void mlxsw_sp_mr_route4_del(struct mlxsw_sp_mr_table *mr_table,
+			    struct mfc_cache *mfc);
+int mlxsw_sp_mr_vif_add(struct mlxsw_sp_mr_table *mr_table,
+			struct net_device *dev, vifi_t vif_index,
+			unsigned long vif_flags,
+			const struct mlxsw_sp_rif *rif);
+void mlxsw_sp_mr_vif_del(struct mlxsw_sp_mr_table *mr_table, vifi_t vif_index);
+int mlxsw_sp_mr_rif_add(struct mlxsw_sp_mr_table *mr_table,
+			const struct mlxsw_sp_rif *rif);
+void mlxsw_sp_mr_rif_del(struct mlxsw_sp_mr_table *mr_table,
+			 const struct mlxsw_sp_rif *rif);
+void mlxsw_sp_mr_rif_mtu_update(struct mlxsw_sp_mr_table *mr_table,
+				const struct mlxsw_sp_rif *rif, int mtu);
+struct mlxsw_sp_mr_table *mlxsw_sp_mr_table_create(struct mlxsw_sp *mlxsw_sp,
+						   u32 tb_id,
+						   enum mlxsw_sp_l3proto proto);
+void mlxsw_sp_mr_table_destroy(struct mlxsw_sp_mr_table *mr_table);
+void mlxsw_sp_mr_table_flush(struct mlxsw_sp_mr_table *mr_table);
+bool mlxsw_sp_mr_table_empty(const struct mlxsw_sp_mr_table *mr_table);
+
+#endif