[PATCH V7 net-next 01/11] devlink: Add 'total_vfs' generic device param

[Saeed Mahameed <saeed@kernel.org>]

From: Vlad Dumitrescu <vdumitrescu@nvidia.com>

NICs are typically configured with total_vfs=0, forcing users to rely
on external tools to enable SR-IOV (a widely used and essential feature).

Add total_vfs parameter to devlink for SR-IOV max VF configurability.
Enables standard kernel tools to manage SR-IOV, addressing the need for
flexible VF configuration.

Signed-off-by: Vlad Dumitrescu <vdumitrescu@nvidia.com>
Tested-by: Kamal Heib <kheib@redhat.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
---
 Documentation/networking/devlink/devlink-params.rst | 5 +++++
 include/net/devlink.h                               | 4 ++++
 net/devlink/param.c                                 | 5 +++++
 3 files changed, 14 insertions(+)

diff --git a/Documentation/networking/devlink/devlink-params.rst b/Documentation/networking/devlink/devlink-params.rst
index 211b58177e12..c51da4fba7e7 100644
--- a/Documentation/networking/devlink/devlink-params.rst
+++ b/Documentation/networking/devlink/devlink-params.rst
@@ -143,3 +143,8 @@ own name.
    * - ``clock_id``
      - u64
      - Clock ID used by the device for registering DPLL devices and pins.
+   * - ``total_vfs``
+     - u32
+     - The max number of Virtual Functions (VFs) exposed by the PF.
+       after reboot/pci reset, 'sriov_totalvfs' entry under the device's sysfs
+       directory will report this value.
diff --git a/include/net/devlink.h b/include/net/devlink.h
index 5f44e702c25c..8d4362f010e4 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -530,6 +530,7 @@ enum devlink_param_generic_id {
 	DEVLINK_PARAM_GENERIC_ID_EVENT_EQ_SIZE,
 	DEVLINK_PARAM_GENERIC_ID_ENABLE_PHC,
 	DEVLINK_PARAM_GENERIC_ID_CLOCK_ID,
+	DEVLINK_PARAM_GENERIC_ID_TOTAL_VFS,
 
 	/* add new param generic ids above here*/
 	__DEVLINK_PARAM_GENERIC_ID_MAX,
@@ -594,6 +595,9 @@ enum devlink_param_generic_id {
 #define DEVLINK_PARAM_GENERIC_CLOCK_ID_NAME "clock_id"
 #define DEVLINK_PARAM_GENERIC_CLOCK_ID_TYPE DEVLINK_PARAM_TYPE_U64
 
+#define DEVLINK_PARAM_GENERIC_TOTAL_VFS_NAME "total_vfs"
+#define DEVLINK_PARAM_GENERIC_TOTAL_VFS_TYPE DEVLINK_PARAM_TYPE_U32
+
 #define DEVLINK_PARAM_GENERIC(_id, _cmodes, _get, _set, _validate)	\
 {									\
 	.id = DEVLINK_PARAM_GENERIC_ID_##_id,				\
diff --git a/net/devlink/param.c b/net/devlink/param.c
index 41dcc86cfd94..33134940c266 100644
--- a/net/devlink/param.c
+++ b/net/devlink/param.c
@@ -102,6 +102,11 @@ static const struct devlink_param devlink_param_generic[] = {
 		.name = DEVLINK_PARAM_GENERIC_CLOCK_ID_NAME,
 		.type = DEVLINK_PARAM_GENERIC_CLOCK_ID_TYPE,
 	},
+	{
+		.id = DEVLINK_PARAM_GENERIC_ID_TOTAL_VFS,
+		.name = DEVLINK_PARAM_GENERIC_TOTAL_VFS_NAME,
+		.type = DEVLINK_PARAM_GENERIC_TOTAL_VFS_TYPE,
+	},
 };
 
 static int devlink_param_generic_verify(const struct devlink_param *param)
-- 
2.51.0