[PATCH net-next 01/14] devlink: define enum for attr types of dynamic attributes

Saeed Mahameed
2025-02-28T02:13:26Z

From: Jiri Pirko <jiri@nvidia.com>

Devlink param and health reporter fmsg use attributes with dynamic type
which is determined according to a different type. Currently used values
are NLA_*. The problem is, they are not part of UAPI. They may change
which would cause a break.

To make this future safe, introduce a enum that shadows NLA_* values in
it and is part of UAPI.

Also, this allows to possibly carry types that are unrelated to NLA_*
values.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
Documentation/netlink/specs/devlink.yaml | 23 ++++++++++++++++++
include/uapi/linux/devlink.h | 17 ++++++++++++++
net/devlink/health.c | 17 ++++++++++++--
net/devlink/param.c | 30 ++++++++++++------------
4 files changed, 70 insertions(+), 17 deletions(-)

diff --git a/Documentation/netlink/specs/devlink.yaml b/Documentation/netlink/specs/devlink.yaml
index 09fbb4c03fc8..e99fc51856c5 100644
--- a/Documentation/netlink/specs/devlink.yaml
+++ b/Documentation/netlink/specs/devlink.yaml
@@ -202,6 +202,29 @@ definitions:
name: exception
-
name: control
+ -
+ type: enum
+ name: dyn_attr_type
+ entries:
+ -
+ name: u8
+ value: 1
+ -
+ name: u16
+ -
+ name: u32
+ -
+ name: u64
+ -
+ name: string
+ -
+ name: flag
+ -
+ name: nul_string
+ value: 10
+ -
+ name: binary
+ -

attribute-sets:
-
diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index 9401aa343673..8cdd60eb3c43 100644
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -385,6 +385,23 @@ enum devlink_linecard_state {
DEVLINK_LINECARD_STATE_MAX = __DEVLINK_LINECARD_STATE_MAX - 1
};

+/**
+ * enum devlink_dyn_attr_type - Dynamic attribute type type.
+ */
+enum devlink_dyn_attr_type {
+ /* Following values relate to the internal NLA_* values */
+ DEVLINK_DYN_ATTR_TYPE_U8 = 1,
+ DEVLINK_DYN_ATTR_TYPE_U16,
+ DEVLINK_DYN_ATTR_TYPE_U32,
+ DEVLINK_DYN_ATTR_TYPE_U64,
+ DEVLINK_DYN_ATTR_TYPE_STRING,
+ DEVLINK_DYN_ATTR_TYPE_FLAG,
+ DEVLINK_DYN_ATTR_TYPE_NUL_STRING = 10,
+ DEVLINK_DYN_ATTR_TYPE_BINARY,
+ __DEVLINK_DYN_ATTR_TYPE_CUSTOM_BASE = 0x80,
+ /* Any possible custom types, unrelated to NLA_* values go below */
+};
+
enum devlink_attr {
/* don't change the order or add anything between, this is ABI! */
DEVLINK_ATTR_UNSPEC,
diff --git a/net/devlink/health.c b/net/devlink/health.c
index 57db6799722a..accb80cd3348 100644
--- a/net/devlink/health.c
+++ b/net/devlink/health.c
@@ -930,18 +930,31 @@ EXPORT_SYMBOL_GPL(devlink_fmsg_binary_pair_put);
static int
devlink_fmsg_item_fill_type(struct devlink_fmsg_item *msg, struct sk_buff *skb)
{
+ enum devlink_dyn_attr_type dyn_attr_type;
+
switch (msg->nla_type) {
case NLA_FLAG:
+ dyn_attr_type = DEVLINK_DYN_ATTR_TYPE_FLAG;
+ break;
case NLA_U8:
+ dyn_attr_type = DEVLINK_DYN_ATTR_TYPE_U8;
+ break;
case NLA_U32:
+ dyn_attr_type = DEVLINK_DYN_ATTR_TYPE_U32;
+ break;
case NLA_U64:
+ dyn_attr_type = DEVLINK_DYN_ATTR_TYPE_U64;
+ break;
case NLA_NUL_STRING:
+ dyn_attr_type = DEVLINK_DYN_ATTR_TYPE_NUL_STRING;
+ break;
case NLA_BINARY:
- return nla_put_u8(skb, DEVLINK_ATTR_FMSG_OBJ_VALUE_TYPE,
- msg->nla_type);
+ dyn_attr_type = DEVLINK_DYN_ATTR_TYPE_BINARY;
+ break;
default:
return -EINVAL;
}
+ return nla_put_u8(skb, DEVLINK_ATTR_FMSG_OBJ_VALUE_TYPE, dyn_attr_type);
}

static int
diff --git a/net/devlink/param.c b/net/devlink/param.c
index dcf0d1ccebba..e19d978dffa6 100644
--- a/net/devlink/param.c
+++ b/net/devlink/param.c
@@ -167,19 +167,19 @@ static int devlink_param_set(struct devlink *devlink,
}

static int
-devlink_param_type_to_nla_type(enum devlink_param_type param_type)
+devlink_param_type_to_dyn_attr_type(enum devlink_param_type param_type)
{
switch (param_type) {
case DEVLINK_PARAM_TYPE_U8:
- return NLA_U8;
+ return DEVLINK_DYN_ATTR_TYPE_U8;
case DEVLINK_PARAM_TYPE_U16:
- return NLA_U16;
+ return DEVLINK_DYN_ATTR_TYPE_U16;
case DEVLINK_PARAM_TYPE_U32:
- return NLA_U32;
+ return DEVLINK_DYN_ATTR_TYPE_U32;
case DEVLINK_PARAM_TYPE_STRING:
- return NLA_STRING;
+ return DEVLINK_DYN_ATTR_TYPE_STRING;
case DEVLINK_PARAM_TYPE_BOOL:
- return NLA_FLAG;
+ return DEVLINK_DYN_ATTR_TYPE_FLAG;
default:
return -EINVAL;
}
@@ -247,7 +247,7 @@ static int devlink_nl_param_fill(struct sk_buff *msg, struct devlink *devlink,
struct devlink_param_gset_ctx ctx;
struct nlattr *param_values_list;
struct nlattr *param_attr;
- int nla_type;
+ int dyn_attr_type;
void *hdr;
int err;
int i;
@@ -294,10 +294,10 @@ static int devlink_nl_param_fill(struct sk_buff *msg, struct devlink *devlink,
if (param->generic && nla_put_flag(msg, DEVLINK_ATTR_PARAM_GENERIC))
goto param_nest_cancel;

- nla_type = devlink_param_type_to_nla_type(param->type);
- if (nla_type < 0)
+ dyn_attr_type = devlink_param_type_to_dyn_attr_type(param->type);
+ if (dyn_attr_type < 0)
goto param_nest_cancel;
- if (nla_put_u8(msg, DEVLINK_ATTR_PARAM_TYPE, nla_type))
+ if (nla_put_u8(msg, DEVLINK_ATTR_PARAM_TYPE, dyn_attr_type))
goto param_nest_cancel;

param_values_list = nla_nest_start_noflag(msg,
@@ -420,19 +420,19 @@ devlink_param_type_get_from_info(struct genl_info *info,
return -EINVAL;

switch (nla_get_u8(info->attrs[DEVLINK_ATTR_PARAM_TYPE])) {
- case NLA_U8:
+ case DEVLINK_DYN_ATTR_TYPE_U8:
*param_type = DEVLINK_PARAM_TYPE_U8;
break;
- case NLA_U16:
+ case DEVLINK_DYN_ATTR_TYPE_U16:
*param_type = DEVLINK_PARAM_TYPE_U16;
break;
- case NLA_U32:
+ case DEVLINK_DYN_ATTR_TYPE_U32:
*param_type = DEVLINK_PARAM_TYPE_U32;
break;
- case NLA_STRING:
+ case DEVLINK_DYN_ATTR_TYPE_STRING:
*param_type = DEVLINK_PARAM_TYPE_STRING;
break;
- case NLA_FLAG:
+ case DEVLINK_DYN_ATTR_TYPE_FLAG:
*param_type = DEVLINK_PARAM_TYPE_BOOL;
break;
default:
--
2.48.1