devlink: add support to create line card and expose to user

Extend the devlink API so the driver is going to be able to create and
destroy linecard instances. There can be multiple line cards per devlink
device. Expose this new type of object over devlink netlink API to the
userspace, with notifications.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/devlink.h

@@ -22,6 +22,7 @@
 #include <linux/firmware.h>
 
 struct devlink;
+struct devlink_linecard;
 
 struct devlink_port_phys_attrs {
 	u32 port_number; /* Same value as "split group".
@@ -1536,6 +1537,9 @@ void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port,
 int devlink_rate_leaf_create(struct devlink_port *port, void *priv);
 void devlink_rate_leaf_destroy(struct devlink_port *devlink_port);
 void devlink_rate_nodes_destroy(struct devlink *devlink);
+struct devlink_linecard *devlink_linecard_create(struct devlink *devlink,
+						 unsigned int linecard_index);
+void devlink_linecard_destroy(struct devlink_linecard *linecard);
 int devlink_sb_register(struct devlink *devlink, unsigned int sb_index,
 			u32 size, u16 ingress_pools_count,
 			u16 egress_pools_count, u16 ingress_tc_count,

include/uapi/linux/devlink.h

@@ -131,6 +131,11 @@ enum devlink_command {
 	DEVLINK_CMD_RATE_NEW,
 	DEVLINK_CMD_RATE_DEL,
 
+	DEVLINK_CMD_LINECARD_GET,		/* can dump */
+	DEVLINK_CMD_LINECARD_SET,
+	DEVLINK_CMD_LINECARD_NEW,
+	DEVLINK_CMD_LINECARD_DEL,
+
 	/* add new commands above here */
 	__DEVLINK_CMD_MAX,
 	DEVLINK_CMD_MAX = __DEVLINK_CMD_MAX - 1
@@ -553,6 +558,8 @@ enum devlink_attr {
 
 	DEVLINK_ATTR_REGION_MAX_SNAPSHOTS,	/* u32 */
 
+	DEVLINK_ATTR_LINECARD_INDEX,		/* u32 */
+
 	/* add new attributes above here, update the policy in devlink.c */
 
 	__DEVLINK_ATTR_MAX,