devlink: Add new "io_eq_size" generic device param

Add new device generic parameter to determine the size of the
I/O completion EQs.

For example, to reduce I/O EQ size to 64, execute:
$ devlink dev param set pci/0000:06:00.0 \
              name io_eq_size value 64 cmode driverinit
$ devlink dev reload pci/0000:06:00.0
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Documentation/networking/devlink/devlink-params.rst

@@ -129,3 +129,6 @@ own name.
        will NACK any attempt of other host to reset the device. This parameter
        is useful for setups where a device is shared by different hosts, such
        as multi-host setup.
+   * - ``io_eq_size``
+     - u32
+     - Control the size of I/O completion EQs.

include/net/devlink.h

@@ -459,6 +459,7 @@ enum devlink_param_generic_id {
 	DEVLINK_PARAM_GENERIC_ID_ENABLE_RDMA,
 	DEVLINK_PARAM_GENERIC_ID_ENABLE_VNET,
 	DEVLINK_PARAM_GENERIC_ID_ENABLE_IWARP,
+	DEVLINK_PARAM_GENERIC_ID_IO_EQ_SIZE,
 
 	/* add new param generic ids above here*/
 	__DEVLINK_PARAM_GENERIC_ID_MAX,
@@ -511,6 +512,9 @@ enum devlink_param_generic_id {
 #define DEVLINK_PARAM_GENERIC_ENABLE_IWARP_NAME "enable_iwarp"
 #define DEVLINK_PARAM_GENERIC_ENABLE_IWARP_TYPE DEVLINK_PARAM_TYPE_BOOL
 
+#define DEVLINK_PARAM_GENERIC_IO_EQ_SIZE_NAME "io_eq_size"
+#define DEVLINK_PARAM_GENERIC_IO_EQ_SIZE_TYPE DEVLINK_PARAM_TYPE_U32
+
 #define DEVLINK_PARAM_GENERIC(_id, _cmodes, _get, _set, _validate)	\
 {									\
 	.id = DEVLINK_PARAM_GENERIC_ID_##_id,				\

net/core/devlink.c

@@ -4466,6 +4466,11 @@ static const struct devlink_param devlink_param_generic[] = {
 		.name = DEVLINK_PARAM_GENERIC_ENABLE_IWARP_NAME,
 		.type = DEVLINK_PARAM_GENERIC_ENABLE_IWARP_TYPE,
 	},
+	{
+		.id = DEVLINK_PARAM_GENERIC_ID_IO_EQ_SIZE,
+		.name = DEVLINK_PARAM_GENERIC_IO_EQ_SIZE_NAME,
+		.type = DEVLINK_PARAM_GENERIC_IO_EQ_SIZE_TYPE,
+	},
 };
 
 static int devlink_param_generic_verify(const struct devlink_param *param)