[RFC net-next 1/2] netdev-genl: Add an XSK attribute to queues

[Joe Damato <jdamato@fastly.com>]

Expose a new per-queue attribute, xsk, which indicates that a queue is
being used for AF_XDP. Update the documentation to more explicitly state
which queue types are linked.

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 Documentation/netlink/specs/netdev.yaml | 10 +++++++++-
 include/uapi/linux/netdev.h             |  1 +
 net/core/netdev-genl.c                  |  6 ++++++
 tools/include/uapi/linux/netdev.h       |  1 +
 4 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index cbb544bd6c84..7a72788cce03 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -286,6 +286,8 @@ attribute-sets:
       -
         name: type
         doc: Queue type as rx, tx. Each queue type defines a separate ID space.
+             XDP TX queues allocated in the kernel are not linked to NAPIs and
+             thus not listed. AF_XDP queues have the xsk attribute set.
         type: u32
         enum: queue-type
       -
@@ -296,7 +298,12 @@ attribute-sets:
         name: dmabuf
         doc: ID of the dmabuf attached to this queue, if any.
         type: u32
-
+      -
+        name: xsk
+        doc: Non-zero for queues which are used for XSK (AF_XDP), 0 otherwise.
+        type: u32
+        checks:
+          max: 1
   -
     name: qstats
     doc: |
@@ -637,6 +644,7 @@ operations:
             - napi-id
             - ifindex
             - dmabuf
+            - xsk
       dump:
         request:
           attributes:
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index e4be227d3ad6..4d2dcf4960ec 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -136,6 +136,7 @@ enum {
 	NETDEV_A_QUEUE_TYPE,
 	NETDEV_A_QUEUE_NAPI_ID,
 	NETDEV_A_QUEUE_DMABUF,
+	NETDEV_A_QUEUE_XSK,
 
 	__NETDEV_A_QUEUE_MAX,
 	NETDEV_A_QUEUE_MAX = (__NETDEV_A_QUEUE_MAX - 1)
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 715f85c6b62e..964aebfcb079 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -394,12 +394,18 @@ netdev_nl_queue_fill_one(struct sk_buff *rsp, struct net_device *netdev,
 		    nla_put_u32(rsp, NETDEV_A_QUEUE_DMABUF, binding->id))
 			goto nla_put_failure;
 
+		if (nla_put_u32(rsp, NETDEV_A_QUEUE_XSK, !!rxq->pool))
+			goto nla_put_failure;
+
 		break;
 	case NETDEV_QUEUE_TYPE_TX:
 		txq = netdev_get_tx_queue(netdev, q_idx);
 		if (txq->napi && nla_put_u32(rsp, NETDEV_A_QUEUE_NAPI_ID,
 					     txq->napi->napi_id))
 			goto nla_put_failure;
+
+		if (nla_put_u32(rsp, NETDEV_A_QUEUE_XSK, !!txq->pool))
+			goto nla_put_failure;
 	}
 
 	genlmsg_end(rsp, hdr);
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index e4be227d3ad6..4d2dcf4960ec 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -136,6 +136,7 @@ enum {
 	NETDEV_A_QUEUE_TYPE,
 	NETDEV_A_QUEUE_NAPI_ID,
 	NETDEV_A_QUEUE_DMABUF,
+	NETDEV_A_QUEUE_XSK,
 
 	__NETDEV_A_QUEUE_MAX,
 	NETDEV_A_QUEUE_MAX = (__NETDEV_A_QUEUE_MAX - 1)
-- 
2.25.1