Merge branch 'netkit-support-for-io_uring-zero-copy-and-af_xdp'

Daniel Borkmann says:

====================
netkit: Support for io_uring zero-copy and AF_XDP

Containers use virtual netdevs to route traffic from a physical netdev
in the host namespace. They do not have access to the physical netdev
in the host and thus can't use memory providers or AF_XDP that require
reconfiguring/restarting queues in the physical netdev.

This patchset adds the concept of queue leasing to virtual netdevs that
allow containers to use memory providers and AF_XDP at native speed.
Leased queues are bound to a real queue in a physical netdev and act
as a proxy.

Memory providers and AF_XDP operations take an ifindex and queue id,
so containers would pass in an ifindex for a virtual netdev and a queue
id of a leased queue, which then gets proxied to the underlying real
queue.

We have implemented support for this concept in netkit and tested the
latter against Nvidia ConnectX-6 (mlx5) as well as Broadcom BCM957504
(bnxt_en) 100G NICs. For more details see the individual patches.
====================

Link: https://patch.msgid.link/20260402231031.447597-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 27 insertions, 2 deletions

diff --git a/include/net/netdev_rx_queue.h b/include/net/netdev_rx_queue.h
index 08f81329fc11..7e98c679ea84 100644
--- a/include/net/netdev_rx_queue.h
+++ b/include/net/netdev_rx_queue.h
@@ -31,6 +31,14 @@ struct netdev_rx_queue {
 	struct napi_struct		*napi;
 	struct netdev_queue_config	qcfg;
 	struct pp_memory_provider_params mp_params;
+
+	/* If a queue is leased, then the lease pointer is always
+	 * valid. From the physical device it points to the virtual
+	 * queue, and from the virtual device it points to the
+	 * physical queue.
+	 */
+	struct netdev_rx_queue		*lease;
+	netdevice_tracker		lease_tracker;
 } ____cacheline_aligned_in_smp;
 
 /*
@@ -59,6 +67,23 @@ get_netdev_rx_queue_index(struct netdev_rx_queue *queue)
 	return index;
 }
 
-int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq);
+enum netif_lease_dir {
+	NETIF_VIRT_TO_PHYS,
+	NETIF_PHYS_TO_VIRT,
+};
 
-#endif
+struct netdev_rx_queue *
+__netif_get_rx_queue_lease(struct net_device **dev, unsigned int *rxq,
+			   enum netif_lease_dir dir);
+
+struct netdev_rx_queue *
+netif_get_rx_queue_lease_locked(struct net_device **dev, unsigned int *rxq);
+void netif_put_rx_queue_lease_locked(struct net_device *orig_dev,
+				     struct net_device *dev);
+
+int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq);
+void netdev_rx_queue_lease(struct netdev_rx_queue *rxq_dst,
+			   struct netdev_rx_queue *rxq_src);
+void netdev_rx_queue_unlease(struct netdev_rx_queue *rxq_dst,
+			     struct netdev_rx_queue *rxq_src);
+#endif /* _LINUX_NETDEV_RX_QUEUE_H */