linux.git/net/core/netdev_rx_queue.c, branch v7.1-rc2

net: Rename ifq_idx to rxq_idx in netif_mp_* helpers

2026-04-12T16:12:07+00:00

Rename the leftover ifq_idx parameter naming to rxq_idx to be
consistent with the rest of the file and the header declaration.
Back then this was taken out of the queue leasing series given
the cleanup is independent. No functional change.

Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/netdev/20260131160237.07789674@kernel.org
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/20260410130602.552600-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

net: remove the netif_get_rx_queue_lease_locked() helpers

2026-04-10T01:26:28+00:00

The netif_get_rx_queue_lease_locked() API hides the locking
and the descend onto the leased queue. Making the code
harder to follow (at least to me). Remove the API and open
code the descend a bit. Most of the code now looks like:

 if (!leased)
     return __helper(x);

 hw_rxq = ..
 netdev_lock(hw_rxq->dev);
 ret = __helper(x);
 netdev_unlock(hw_rxq->dev);

 return ret;

Of course if we have more code paths that need the wrapping
we may need to revisit. For now, IMHO, having to know what
netif_get_rx_queue_lease_locked() does is not worth the 20LoC
it saves.

Link: https://patch.msgid.link/20260408151251.72bd2482@kernel.org
Signed-off-by: Jakub Kicinski

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

2026-04-10T01:24:35+00:00

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

net: Proxy netif_mp_{open,close}_rxq for leased queues

2026-04-10T01:21:46+00:00

When a process in a container wants to setup a memory provider, it will
use the virtual netdev and a leased rxq, and call netif_mp_{open,close}_rxq
to try and restart the queue. At this point, proxy the queue restart on
the real rxq in the physical netdev.

For memory providers (io_uring zero-copy rx and devmem), it causes the
real rxq in the physical netdev to be filled from a memory provider that
has DMA mapped memory from a process within a container.

Signed-off-by: David Wei 
Co-developed-by: Daniel Borkmann 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/20260402231031.447597-7-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

net: Slightly simplify net_mp_{open,close}_rxq

2026-04-10T01:21:46+00:00

net_mp_open_rxq is currently not used in the tree as all callers are
using __net_mp_open_rxq directly, and net_mp_close_rxq is only used
once while all other locations use __net_mp_close_rxq.

Consolidate into a single API, netif_mp_{open,close}_rxq, using the
netif_ prefix to indicate that the caller is responsible for locking.

Signed-off-by: Daniel Borkmann 
Co-developed-by: David Wei 
Signed-off-by: David Wei 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/20260402231031.447597-6-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

net: Add lease info to queue-get response

2026-04-10T01:21:46+00:00

Populate nested lease info to the queue-get response that returns the
ifindex, queue id with type and optionally netns id if the device
resides in a different netns.

Example with ynl client when using AF_XDP via queue leasing:

  # ip a
  [...]
  4: enp10s0f0np0:  mtu 1500 xdp/id:24 qdisc mq state UP group default qlen 1000
    link/ether e8:eb:d3:a3:43:f6 brd ff:ff:ff:ff:ff:ff
    inet 10.0.0.2/24 scope global enp10s0f0np0
       valid_lft forever preferred_lft forever
    inet6 fe80::eaeb:d3ff:fea3:43f6/64 scope link proto kernel_ll
       valid_lft forever preferred_lft forever
  [...]

  # ethtool -i enp10s0f0np0
  driver: mlx5_core
  [...]

  # ynl --family netdev --output-json --do queue-get \
        --json '{"ifindex": 4, "id": 15, "type": "rx"}'
  {'id': 15,
   'ifindex': 4,
   'lease': {'ifindex': 8, 'netns-id': 0, 'queue': {'id': 1, 'type': 'rx'}},
   'napi-id': 8227,
   'type': 'rx',
   'xsk': {}}

  # ip netns list
  foo (id: 0)

  # ip netns exec foo ip a
  [...]
  8: nk@NONE:  mtu 1500 qdisc noqueue state UP group default qlen 1000
      link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
      inet6 fe80::200:ff:fe00:0/64 scope link proto kernel_ll
         valid_lft forever preferred_lft forever
  [...]

  # ip netns exec foo ethtool -i nk
  driver: netkit
  [...]

  # ip netns exec foo ls /sys/class/net/nk/queues/
  rx-0  rx-1  tx-0

  # ip netns exec foo ynl --family netdev --output-json --do queue-get \
        --json '{"ifindex": 8, "id": 1, "type": "rx"}'
  {"id": 1, "type": "rx", "ifindex": 8, "xsk": {}}

Note that the caller of netdev_nl_queue_fill_one() holds the netdevice
lock. For the queue-get we do not lock both devices. When queues get
{un,}leased, both devices are locked, thus if __netif_get_rx_queue_lease()
returns a lease pointer, it points to a valid device. The netns-id is
fetched via peernet2id_alloc() similarly as done in OVS.

Signed-off-by: Daniel Borkmann 
Co-developed-by: David Wei 
Signed-off-by: David Wei 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/20260402231031.447597-4-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

net: Implement netdev_nl_queue_create_doit

2026-04-10T01:21:45+00:00

Implement netdev_nl_queue_create_doit which creates a new rx queue in a
virtual netdev and then leases it to a rx queue in a physical netdev.

Example with ynl client:

  # ynl --family netdev --output-json --do queue-create \
        --json '{"ifindex": 8, "type": "rx", "lease": {"ifindex": 4, "queue": {"type": "rx", "id": 15}}}'
  {'id': 1}

Note that the netdevice locking order is always from the virtual to
the physical device.

Signed-off-by: Daniel Borkmann 
Co-developed-by: David Wei 
Signed-off-by: David Wei 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/20260402231031.447597-3-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

net: avoid nul-deref trying to bind mp to incapable device

2026-04-08T01:57:56+00:00

Sashiko points out that we use qops in __net_mp_open_rxq()
but never validate they are null. This was introduced when
check was moved from netdev_rx_queue_restart().

Look at ops directly instead of the locking config.
qops imply netdev_need_ops_lock(). We used netdev_need_ops_lock()
initially to signify that the real_num_rx_queues check below
is safe without rtnl_lock, but I'm not sure if this is actually
clear to most people, anyway.

Fixes: da7772a2b4ad ("net: move mp->rx_page_size validation to __net_mp_open_rxq()")
Acked-by: Daniel Borkmann 
Reviewed-by: Mina Almasry 
Link: https://patch.msgid.link/20260404001938.2425670-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski

net: add queue config validation callback

2026-01-23T19:49:02+00:00

I imagine (tm) that as the number of per-queue configuration
options grows some of them may conflict for certain drivers.
While the drivers can obviously do all the validation locally
doing so is fairly inconvenient as the config is fed to drivers
piecemeal via different ops (for different params and NIC-wide
vs per-queue).

Add a centralized callback for validating the queue config
in queue ops. The callback gets invoked before memory provider
is installed, and in the future should also be called when ring
params are modified.

The validation is done after each layer of configuration.
Since we can't fail MP un-binding we must make sure that
the config is valid both before and after MP overrides are
applied. This is moot for now since the set of MP and device
configs are disjoint. It will matter significantly in the future,
so adding it now so that we don't forget..

Link: https://patch.msgid.link/20260122005113.2476634-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski

net: use netdev_queue_config() for mp restart

2026-01-23T19:49:02+00:00

We should follow the prepare/commit approach for queue configuration.
The qcfg struct should be added to dev->cfg rather than directly to
queue objects so that we can clone and discard the pending config
easily.

Remove the qcfg in struct netdev_rx_queue, and switch remaining callers
to netdev_queue_config(). netdev_queue_config() will construct the qcfg
on the fly based on device defaults and state of the queue.

ndo_default_qcfg becomes optional because having the callback itself
does not have any meaningful semantics to us.

Reviewed-by: Dragos Tatulea 
Link: https://patch.msgid.link/20260122005113.2476634-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski