[PATCH net-next 08/14] devlink: Implement get/dump netlink commands for port params

Saeed Mahameed
2025-02-28T02:13:31Z

From: Saeed Mahameed <saeedm@nvidia.com>

Add missing port-params netlink attributes and policies to devlink's
spec, reuse existing get_doit/dump_doit of the devlink params for port
params and implement the dump command for all devlink ports params.

This implements:
1) devlink port param show
2) devlink port param show <device>/<port>
3) devlink port param show <device>/<port> name <param_name>

Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
---
Documentation/netlink/specs/devlink.yaml | 13 ++--
include/net/devlink.h | 1 +
net/devlink/netlink_gen.c | 16 ++++-
net/devlink/param.c | 88 ++++++++++++++++++++----
4 files changed, 99 insertions(+), 19 deletions(-)

diff --git a/Documentation/netlink/specs/devlink.yaml b/Documentation/netlink/specs/devlink.yaml
index e99fc51856c5..fb3b2bea0ac3 100644
--- a/Documentation/netlink/specs/devlink.yaml
+++ b/Documentation/netlink/specs/devlink.yaml
@@ -1851,12 +1851,17 @@ operations:
pre: devlink-nl-pre-doit-port
post: devlink-nl-post-doit
request:
- attributes: *port-id-attrs
- reply:
- attributes: *port-id-attrs
+ attributes: &port-param-id-attrs
+ - bus-name
+ - dev-name
+ - port-index
+ - param-name
+ reply: &port-param-get-reply
+ attributes: *port-param-id-attrs
dump:
- reply:
+ request:
attributes: *port-id-attrs
+ reply: *port-param-get-reply

-
name: port-param-set
diff --git a/include/net/devlink.h b/include/net/devlink.h
index 11f98e3a750b..b409ccbcfd12 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -439,6 +439,7 @@ union devlink_param_value {
struct devlink_param_gset_ctx {
union devlink_param_value val;
enum devlink_param_cmode cmode;
+ struct devlink_port *devlink_port;
};

/**
diff --git a/net/devlink/netlink_gen.c b/net/devlink/netlink_gen.c
index f9786d51f68f..d4876cf0f049 100644
--- a/net/devlink/netlink_gen.c
+++ b/net/devlink/netlink_gen.c
@@ -322,7 +322,15 @@ static const struct nla_policy devlink_region_read_nl_policy[DEVLINK_ATTR_REGION
};

/* DEVLINK_CMD_PORT_PARAM_GET - do */
-static const struct nla_policy devlink_port_param_get_nl_policy[DEVLINK_ATTR_PORT_INDEX + 1] = {
+static const struct nla_policy devlink_port_param_get_do_nl_policy[DEVLINK_ATTR_PARAM_NAME + 1] = {
+ [DEVLINK_ATTR_BUS_NAME] = { .type = NLA_NUL_STRING, },
+ [DEVLINK_ATTR_DEV_NAME] = { .type = NLA_NUL_STRING, },
+ [DEVLINK_ATTR_PORT_INDEX] = { .type = NLA_U32, },
+ [DEVLINK_ATTR_PARAM_NAME] = { .type = NLA_NUL_STRING, },
+};
+
+/* DEVLINK_CMD_PORT_PARAM_GET - dump */
+static const struct nla_policy devlink_port_param_get_dump_nl_policy[DEVLINK_ATTR_PORT_INDEX + 1] = {
[DEVLINK_ATTR_BUS_NAME] = { .type = NLA_NUL_STRING, },
[DEVLINK_ATTR_DEV_NAME] = { .type = NLA_NUL_STRING, },
[DEVLINK_ATTR_PORT_INDEX] = { .type = NLA_U32, },
@@ -938,14 +946,16 @@ const struct genl_split_ops devlink_nl_ops[74] = {
.pre_doit = devlink_nl_pre_doit_port,
.doit = devlink_nl_port_param_get_doit,
.post_doit = devlink_nl_post_doit,
- .policy = devlink_port_param_get_nl_policy,
- .maxattr = DEVLINK_ATTR_PORT_INDEX,
+ .policy = devlink_port_param_get_do_nl_policy,
+ .maxattr = DEVLINK_ATTR_PARAM_NAME,
.flags = GENL_CMD_CAP_DO,
},
{
.cmd = DEVLINK_CMD_PORT_PARAM_GET,
.validate = GENL_DONT_VALIDATE_DUMP_STRICT,
.dumpit = devlink_nl_port_param_get_dumpit,
+ .policy = devlink_port_param_get_dump_nl_policy,
+ .maxattr = DEVLINK_ATTR_PORT_INDEX,
.flags = GENL_CMD_CAP_DUMP,
},
{
diff --git a/net/devlink/param.c b/net/devlink/param.c
index 719eeb5152c3..45f1847f9435 100644
--- a/net/devlink/param.c
+++ b/net/devlink/param.c
@@ -153,11 +153,14 @@ devlink_param_cmode_is_supported(const struct devlink_param *param,
}

static int devlink_param_get(struct devlink *devlink,
+ struct devlink_port *devlink_port,
const struct devlink_param *param,
struct devlink_param_gset_ctx *ctx)
{
if (!param->get)
return -EOPNOTSUPP;
+
+ ctx->devlink_port = devlink_port;
return param->get(devlink, param->id, ctx);
}

@@ -249,7 +252,7 @@ static int devlink_nl_param_fill(struct sk_buff *msg, struct devlink *devlink,
union devlink_param_value param_value[DEVLINK_PARAM_CMODE_MAX + 1];
bool param_value_set[DEVLINK_PARAM_CMODE_MAX + 1] = {};
const struct devlink_param *param = param_item->param;
- struct devlink_param_gset_ctx ctx;
+ struct devlink_param_gset_ctx ctx = {};
struct nlattr *param_values_list;
struct nlattr *param_attr;
int dyn_attr_type;
@@ -270,7 +273,7 @@ static int devlink_nl_param_fill(struct sk_buff *msg, struct devlink *devlink,
return -EOPNOTSUPP;
} else {
ctx.cmode = i;
- err = devlink_param_get(devlink, param, &ctx);
+ err = devlink_param_get(devlink, devlink_port, param, &ctx);
if (err)
return err;
param_value[i] = ctx.val;
@@ -505,15 +508,17 @@ devlink_param_get_from_info(struct xarray *params, struct genl_info *info)
return devlink_param_find_by_name(params, param_name);
}

-int devlink_nl_param_get_doit(struct sk_buff *skb,
- struct genl_info *info)
+static int __devlink_nl_param_get_doit(struct devlink *devlink,
+ struct devlink_port *devlink_port,
+ struct xarray *params,
+ struct genl_info *info,
+ enum devlink_command cmd)
{
- struct devlink *devlink = info->user_ptr[0];
struct devlink_param_item *param_item;
struct sk_buff *msg;
int err;

- param_item = devlink_param_get_from_info(&devlink->params, info);
+ param_item = devlink_param_get_from_info(params, info);
if (!param_item)
return -EINVAL;

@@ -521,8 +526,7 @@ int devlink_nl_param_get_doit(struct sk_buff *skb,
if (!msg)
return -ENOMEM;

- err = devlink_nl_param_fill(msg, devlink, NULL, param_item,
- DEVLINK_CMD_PARAM_GET,
+ err = devlink_nl_param_fill(msg, devlink, devlink_port, param_item, cmd,
info->snd_portid, info->snd_seq, 0);
if (err) {
nlmsg_free(msg);
@@ -532,6 +536,14 @@ int devlink_nl_param_get_doit(struct sk_buff *skb,
return genlmsg_reply(msg, info);
}

+int devlink_nl_param_get_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ struct devlink *devlink = info->user_ptr[0];
+
+ return __devlink_nl_param_get_doit(devlink, NULL, &devlink->params,
+ info, DEVLINK_CMD_PARAM_GET);
+}
+
static int __devlink_nl_cmd_param_set_doit(struct devlink *devlink,
struct devlink_port *devlink_port,
struct xarray *params,
@@ -595,18 +607,70 @@ int devlink_nl_param_set_doit(struct sk_buff *skb, struct genl_info *info)
info, DEVLINK_CMD_PARAM_NEW);
}

+static int
+devlink_nl_port_param_get_dump_one(struct sk_buff *msg,
+ struct devlink *devlink,
+ struct netlink_callback *cb,
+ int flags)
+{
+ struct devlink_nl_dump_state *state = devlink_dump_state(cb);
+ const struct genl_info *info = genl_info_dump(cb);
+ unsigned long port_index_end = ULONG_MAX;
+ struct devlink_param_item *param_item;
+ struct nlattr **attrs = info->attrs;
+ unsigned long port_index_start = 0;
+ struct devlink_port *devlink_port;
+ unsigned long port_index;
+ unsigned long param_id;
+ int idx = 0;
+ int err = 0;
+
+ if (attrs && attrs[DEVLINK_ATTR_PORT_INDEX]) {
+ port_index_start = nla_get_u32(attrs[DEVLINK_ATTR_PORT_INDEX]);
+ port_index_end = port_index_start;
+ flags |= NLM_F_DUMP_FILTERED;
+ }
+
+ xa_for_each_range(&devlink->ports, port_index, devlink_port,
+ port_index_start, port_index_end) {
+ xa_for_each_start(&devlink_port->params, param_id, param_item,
+ state->idx) {
+ if (idx < state->idx) {
+ idx++;
+ continue;
+ }
+ err = devlink_nl_param_fill(msg, devlink, devlink_port,
+ param_item,
+ DEVLINK_CMD_PORT_PARAM_GET,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, flags);
+ if (err == -EOPNOTSUPP) {
+ err = 0;
+ } else if (err) {
+ state->idx = param_id;
+ break;
+ }
+ }
+ }
+
+ return err;
+}
+
int devlink_nl_port_param_get_dumpit(struct sk_buff *msg,
struct netlink_callback *cb)
{
- NL_SET_ERR_MSG(cb->extack, "Port params are not supported");
- return msg->len;
+ return devlink_nl_dumpit(msg, cb, devlink_nl_port_param_get_dump_one);
}

int devlink_nl_port_param_get_doit(struct sk_buff *skb,
struct genl_info *info)
{
- NL_SET_ERR_MSG(info->extack, "Port params are not supported");
- return -EINVAL;
+ struct devlink_port *devlink_port = info->user_ptr[1];
+ struct devlink *devlink = info->user_ptr[0];
+
+ return __devlink_nl_param_get_doit(devlink, devlink_port,
+ &devlink_port->params,
+ info, DEVLINK_CMD_PORT_PARAM_GET);
}

int devlink_nl_port_param_set_doit(struct sk_buff *skb,
--
2.48.1