Merge branch 'Expose-port-split-attributes'

Ido Schimmel says:

====================
Expose port split attributes

Danielle says:

Currently, user space has no way of knowing if a port can be split and
into how many ports. Among other things, this makes it impossible to
write generic tests for port split functionality.

Therefore, this set exposes two new devlink port attributes to user
space: Number of lanes and whether the port can be split or not.

Patch set overview:

Patches #1-#4 cleanup 'struct devlink_port_attrs' and reduce the number
of parameters passed between drivers and devlink via
devlink_port_attrs_set()

Patch #5 adds devlink port lanes attributes

Patches #6-#7 add devlink port splittable attribute

Patch #8 exploits the fact that devlink is now aware of port's number of
lanes and whether the port can be split or not and moves some checks
from drivers to devlink

Patch #9 adds a port split test

Changes since v2:
* Remove some local variables from patch #3
* Reword function description in patch #5
* Fix a bug in patch #8
* Add a test for the splittable attribute in patch #9

Changes since v1:
* Rename 'width' attribute to 'lanes'
* Add 'splittable' attribute
* Move checks from drivers to devlink
====================

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 19 insertions, 14 deletions

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 428f55f8197c..746bed538664 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -52,7 +52,7 @@ struct devlink_port_phys_attrs {
 			  * A physical port which is visible to the user
 			  * for a given port flavour.
 			  */
-	u32 split_subport_number;
+	u32 split_subport_number; /* If the port is split, this is the number of subport. */
 };
 
 struct devlink_port_pci_pf_attrs {
@@ -64,10 +64,18 @@ struct devlink_port_pci_vf_attrs {
 	u16 vf;	/* Associated PCI VF for of the PCI PF for this port. */
 };
 
+/**
+ * struct devlink_port_attrs - devlink port object
+ * @flavour: flavour of the port
+ * @split: indicates if this is split port
+ * @splittable: indicates if the port can be split.
+ * @lanes: maximum number of lanes the port supports. 0 value is not passed to netlink.
+ * @switch_id: if the port is part of switch, this is buffer with ID, otherwise this is NULL
+ */
 struct devlink_port_attrs {
-	u8 set:1,
-	   split:1,
-	   switch_port:1;
+	u8 split:1,
+	   splittable:1;
+	u32 lanes;
 	enum devlink_port_flavour flavour;
 	struct netdev_phys_item_id switch_id;
 	union {
@@ -90,6 +98,8 @@ struct devlink_port {
 	enum devlink_port_type desired_type;
 	void *type_dev;
 	struct devlink_port_attrs attrs;
+	u8 attrs_set:1,
+	   switch_port:1;
 	struct delayed_work type_warn_dw;
 };
 
@@ -1180,17 +1190,9 @@ void devlink_port_type_ib_set(struct devlink_port *devlink_port,
 			      struct ib_device *ibdev);
 void devlink_port_type_clear(struct devlink_port *devlink_port);
 void devlink_port_attrs_set(struct devlink_port *devlink_port,
-			    enum devlink_port_flavour flavour,
-			    u32 port_number, bool split,
-			    u32 split_subport_number,
-			    const unsigned char *switch_id,
-			    unsigned char switch_id_len);
-void devlink_port_attrs_pci_pf_set(struct devlink_port *devlink_port,
-				   const unsigned char *switch_id,
-				   unsigned char switch_id_len, u16 pf);
+			    struct devlink_port_attrs *devlink_port_attrs);
+void devlink_port_attrs_pci_pf_set(struct devlink_port *devlink_port, u16 pf);
 void devlink_port_attrs_pci_vf_set(struct devlink_port *devlink_port,
-				   const unsigned char *switch_id,
-				   unsigned char switch_id_len,
 				   u16 pf, u16 vf);
 int devlink_sb_register(struct devlink *devlink, unsigned int sb_index,
 			u32 size, u16 ingress_pools_count,
diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index 87c83a82991b..cfef4245ea5a 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -455,6 +455,9 @@ enum devlink_attr {
 
 	DEVLINK_ATTR_INFO_BOARD_SERIAL_NUMBER,	/* string */
 
+	DEVLINK_ATTR_PORT_LANES,			/* u32 */
+	DEVLINK_ATTR_PORT_SPLITTABLE,			/* u8 */
+
 	/* add new attributes above here, update the policy in devlink.c */
 
 	__DEVLINK_ATTR_MAX,