Re: [PATCH net-next V4 10/12] devlink: Add resource scope filtering to resource dump

Or Har-Toov
2026-04-06T16:18:54Z

On 03/04/2026 5:02, Jakub Kicinski wrote:
>
> On Wed, 1 Apr 2026 21:49:45 +0300 Tariq Toukan wrote:
>> @@ -873,6 +881,16 @@ attribute-sets:
>> doc: Unique devlink instance index.
>> checks:
>> max: u32-max
>> + -
>> + name: resource-scope-mask
>> + type: bitfield32
>
> no need for a bitfield here, this is a simpler selector
> bitfield is for cases when we need to update some persistent
> state, in that case we want to indicate which bits we intend
> to update:
>
> cfg = (cfg & ~bf.mask) | bf.val
>
> scope is a straight attribute, there's no updating of anything.
>
> u32 or unit would do

ack, will use u32 for resource scope mask

>
>> + enum: resource-scope
>> + enum-as-flags: true
>> + doc: |
>> + Bitmask selecting which resource classes to include in a
>> + resource-dump response. Bit 0 (dev) selects device-level
>> + resources; bit 1 (port) selects port-level resources.
>> + When absent all classes are returned.
>> -
>> name: dl-dev-stats
>> subset-of: devlink
>> @@ -1775,7 +1793,11 @@ operations:
>> - resource-list
>> dump:
>> request:
>> - attributes: *dev-id-attrs
>> + attributes:
>> + - bus-name
>> + - dev-name
>> + - index
>> + - resource-scope-mask
>> reply: *resource-dump-reply
>>
>> -
>> diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
>> index 7de2d8cc862f..e0a0b523ce5c 100644
>> --- a/include/uapi/linux/devlink.h
>> +++ b/include/uapi/linux/devlink.h
>> @@ -645,6 +645,7 @@ enum devlink_attr {
>> DEVLINK_ATTR_PARAM_RESET_DEFAULT, /* flag */
>>
>> DEVLINK_ATTR_INDEX, /* uint */
>> + DEVLINK_ATTR_RESOURCE_SCOPE_MASK, /* bitfield32 */
>>
>> /* Add new attributes above here, update the spec in
>> * Documentation/netlink/specs/devlink.yaml and re-generate
>> @@ -704,6 +705,22 @@ enum devlink_resource_unit {
>> DEVLINK_RESOURCE_UNIT_ENTRY,
>> };
>>
>> +enum devlink_resource_scope {
>> + DEVLINK_RESOURCE_SCOPE_DEV_BIT,
>> + DEVLINK_RESOURCE_SCOPE_PORT_BIT,
>> +
>> + __DEVLINK_RESOURCE_SCOPE_MAX_BIT,
>> + DEVLINK_RESOURCE_SCOPE_MAX_BIT =
>
> do we need this? it's not an attr enum all we care about here is
> the mask, really so just a trailing value which is max real value + 1
> is enough for all users?
>

ok, can manage without max at all, can manage also without
DEVLINK_RESOURCE_SCOPE_VALID_MASK

>> + __DEVLINK_RESOURCE_SCOPE_MAX_BIT - 1
>> +};
>> +
>> +#define DEVLINK_RESOURCE_SCOPE_DEV \
>> + _BITUL(DEVLINK_RESOURCE_SCOPE_DEV_BIT)
>> +#define DEVLINK_RESOURCE_SCOPE_PORT \
>> + _BITUL(DEVLINK_RESOURCE_SCOPE_PORT_BIT)
>> +#define DEVLINK_RESOURCE_SCOPE_VALID_MASK \
>> + (_BITUL(__DEVLINK_RESOURCE_SCOPE_MAX_BIT) - 1)
>> +
>> enum devlink_port_fn_attr_cap {
>> DEVLINK_PORT_FN_ATTR_CAP_ROCE_BIT,
>> DEVLINK_PORT_FN_ATTR_CAP_MIGRATABLE_BIT,
>
>> +static u32 devlink_resource_scope_get(struct nlattr **attrs, int *flags)
>> +{
>> + struct nla_bitfield32 scope;
>> + u32 value;
>> +
>> + if (!attrs || !attrs[DEVLINK_ATTR_RESOURCE_SCOPE_MASK])
>> + return DEVLINK_RESOURCE_SCOPE_VALID_MASK;
>> +
>> + scope = nla_get_bitfield32(attrs[DEVLINK_ATTR_RESOURCE_SCOPE_MASK]);
>> + value = scope.value & scope.selector;
>> + if (value != DEVLINK_RESOURCE_SCOPE_VALID_MASK)
>> + *flags |= NLM_F_DUMP_FILTERED;
>> +
>> + return value;
>> +}
>> +
>> static int
>> devlink_resource_dump_fill_one(struct sk_buff *skb, struct devlink *devlink,
>> struct devlink_port *devlink_port,
>> @@ -400,16 +416,27 @@ devlink_nl_resource_dump_one(struct sk_buff *skb, struct devlink *devlink,
>> struct devlink_nl_dump_state *state = devlink_dump_state(cb);
>> struct devlink_port *devlink_port;
>> unsigned long port_idx;
>> + u32 scope;
>> int err;
>>
>> - if (!state->port_number) {
>> + scope = devlink_resource_scope_get(genl_info_dump(cb)->attrs, &flags);
>> + if (!scope) {
>> + NL_SET_ERR_MSG_ATTR(genl_info_dump(cb)->extack,
>> + genl_info_dump(cb)->attrs[DEVLINK_ATTR_RESOURCE_SCOPE_MASK],
>
> we have genl_info_dump(cb) 3 times here, let's save the pointer
> on the stack to make the lines shorter.
>

ack

>> + "empty resource scope selection");
>> + return -EINVAL;
>> + }
>> + if (!state->port_number && (scope & DEVLINK_RESOURCE_SCOPE_DEV)) {
>> err = devlink_resource_dump_fill_one(skb, devlink, NULL,
>> - cb, flags, &state->idx);
>> + cb, flags,
>> + &state->idx);
>> if (err)
>> return err;
>> state->idx = 0;
>> }
>>
>> + if (!(scope & DEVLINK_RESOURCE_SCOPE_PORT))
>> + goto out;
>> xa_for_each_start(&devlink->ports, port_idx, devlink_port,
>> state->port_number ? state->port_number - 1 : 0) {
>> err = devlink_resource_dump_fill_one(skb, devlink, devlink_port,
>> @@ -420,6 +447,7 @@ devlink_nl_resource_dump_one(struct sk_buff *skb, struct devlink *devlink,
>> }
>> state->idx = 0;
>> }
>> +out:
>> state->port_number = 0;
>> return 0;
>> }
>