devlink: Add tunnel generic packet traps

Add packet traps that can report packets that were dropped during tunnel
decapsulation.
Signed-off-by: Amit Cohen <amitc@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/devlink/devlink-trap.rst

@@ -229,6 +229,11 @@ be added to the following table:
        supposed to be routed. For example, IGMP queries can be flooded by the
        device in layer 2 and reach the router. Such packets should not be
        routed and instead dropped
+   * - ``decap_error``
+     - ``exception``
+     - Traps NVE and IPinIP packets that the device decided to drop because of
+       failure during decapsulation (e.g., packet being too short, reserved
+       bits set in VXLAN header)
 
 Driver-specific Packet Traps
 ============================
@@ -265,6 +270,9 @@ narrow. The description of these groups must be added to the following table:
    * - ``buffer_drops``
      - Contains packet traps for packets that were dropped by the device due to
        an enqueue decision
+   * - ``tunnel_drops``
+     - Contains packet traps for packets that were dropped by the device during
+       tunnel encapsulation / decapsulation
 
 Testing
 =======

include/net/devlink.h

@@ -592,6 +592,7 @@ enum devlink_trap_generic_id {
 	DEVLINK_TRAP_GENERIC_ID_IPV4_LPM_UNICAST_MISS,
 	DEVLINK_TRAP_GENERIC_ID_IPV6_LPM_UNICAST_MISS,
 	DEVLINK_TRAP_GENERIC_ID_NON_ROUTABLE,
+	DEVLINK_TRAP_GENERIC_ID_DECAP_ERROR,
 
 	/* Add new generic trap IDs above */
 	__DEVLINK_TRAP_GENERIC_ID_MAX,
@@ -605,6 +606,7 @@ enum devlink_trap_group_generic_id {
 	DEVLINK_TRAP_GROUP_GENERIC_ID_L2_DROPS,
 	DEVLINK_TRAP_GROUP_GENERIC_ID_L3_DROPS,
 	DEVLINK_TRAP_GROUP_GENERIC_ID_BUFFER_DROPS,
+	DEVLINK_TRAP_GROUP_GENERIC_ID_TUNNEL_DROPS,
 
 	/* Add new generic trap group IDs above */
 	__DEVLINK_TRAP_GROUP_GENERIC_ID_MAX,
@@ -662,6 +664,8 @@ enum devlink_trap_group_generic_id {
 	"ipv6_lpm_miss"
 #define DEVLINK_TRAP_GENERIC_NAME_NON_ROUTABLE \
 	"non_routable_packet"
+#define DEVLINK_TRAP_GENERIC_NAME_DECAP_ERROR \
+	"decap_error"
 
 #define DEVLINK_TRAP_GROUP_GENERIC_NAME_L2_DROPS \
 	"l2_drops"
@@ -669,6 +673,8 @@ enum devlink_trap_group_generic_id {
 	"l3_drops"
 #define DEVLINK_TRAP_GROUP_GENERIC_NAME_BUFFER_DROPS \
 	"buffer_drops"
+#define DEVLINK_TRAP_GROUP_GENERIC_NAME_TUNNEL_DROPS \
+	"tunnel_drops"
 
 #define DEVLINK_TRAP_GENERIC(_type, _init_action, _id, _group, _metadata_cap) \
 	{								      \

net/core/devlink.c

@@ -7707,6 +7707,7 @@ static const struct devlink_trap devlink_trap_generic[] = {
 	DEVLINK_TRAP(IPV4_LPM_UNICAST_MISS, EXCEPTION),
 	DEVLINK_TRAP(IPV6_LPM_UNICAST_MISS, EXCEPTION),
 	DEVLINK_TRAP(NON_ROUTABLE, DROP),
+	DEVLINK_TRAP(DECAP_ERROR, EXCEPTION),
 };
 
 #define DEVLINK_TRAP_GROUP(_id)						      \
@@ -7719,6 +7720,7 @@ static const struct devlink_trap_group devlink_trap_group_generic[] = {
 	DEVLINK_TRAP_GROUP(L2_DROPS),
 	DEVLINK_TRAP_GROUP(L3_DROPS),
 	DEVLINK_TRAP_GROUP(BUFFER_DROPS),
+	DEVLINK_TRAP_GROUP(TUNNEL_DROPS),
 };
 
 static int devlink_trap_generic_verify(const struct devlink_trap *trap)