netdev: add io_uring memory provider info

Add a nested attribute for io_uring memory provider info. For now it is
empty and its presence indicates that a particular page pool or queue
has an io_uring memory provider attached.

$ ./cli.py --spec netlink/specs/netdev.yaml --dump page-pool-get
[{'id': 80,
  'ifindex': 2,
  'inflight': 64,
  'inflight-mem': 262144,
  'napi-id': 525},
 {'id': 79,
  'ifindex': 2,
  'inflight': 320,
  'inflight-mem': 1310720,
  'io_uring': {},
  'napi-id': 525},
...

$ ./cli.py --spec netlink/specs/netdev.yaml --dump queue-get
[{'id': 0, 'ifindex': 1, 'type': 'rx'},
 {'id': 0, 'ifindex': 1, 'type': 'tx'},
 {'id': 0, 'ifindex': 2, 'napi-id': 513, 'type': 'rx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 514, 'type': 'rx'},
...
 {'id': 12, 'ifindex': 2, 'io_uring': {}, 'napi-id': 525, 'type': 'rx'},
...

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: David Wei <dw@davidwei.uk>
Link: https://patch.msgid.link/20250204215622.695511-6-dw@davidwei.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/netlink/specs/netdev.yaml

@@ -114,6 +114,9 @@ attribute-sets:
         doc: Bitmask of enabled AF_XDP features.
         type: u64
         enum: xsk-flags
+  -
+    name: io-uring-provider-info
+    attributes: []
   -
     name: page-pool
     attributes:
@@ -171,6 +174,11 @@ attribute-sets:
         name: dmabuf
         doc: ID of the dmabuf this page-pool is attached to.
         type: u32
+      -
+        name: io-uring
+        doc: io-uring memory provider information.
+        type: nest
+        nested-attributes: io-uring-provider-info
   -
     name: page-pool-info
     subset-of: page-pool
@@ -296,6 +304,11 @@ attribute-sets:
         name: dmabuf
         doc: ID of the dmabuf attached to this queue, if any.
         type: u32
+      -
+        name: io-uring
+        doc: io_uring memory provider information.
+        type: nest
+        nested-attributes: io-uring-provider-info
 
   -
     name: qstats
@@ -572,6 +585,7 @@ operations:
             - inflight-mem
             - detach-time
             - dmabuf
+            - io-uring
       dump:
         reply: *pp-reply
       config-cond: page-pool
@@ -637,6 +651,7 @@ operations:
             - napi-id
             - ifindex
             - dmabuf
+            - io-uring
       dump:
         request:
           attributes: