[PATCH net-next v9 06/14] net: Proxy netif_mp_{open,close}_rxq for leased queues
From: Daniel Borkmann <daniel@iogearbox.net>
Date: 2026-03-20 22:18:46
Also in:
bpf
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: David Wei <redacted>
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 <redacted>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
net/core/dev.h | 2 +
net/core/netdev_rx_queue.c | 93 +++++++++++++++++++++++++++++++-------
2 files changed, 78 insertions(+), 17 deletions(-)
diff --git a/net/core/dev.h b/net/core/dev.h
index 854d5e43bdbf..56831cb3d1c2 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h@@ -101,6 +101,8 @@ int netdev_queue_config_validate(struct net_device *dev, int rxq_idx, bool netif_rxq_has_mp(struct net_device *dev, unsigned int rxq_idx); bool netif_rxq_is_leased(struct net_device *dev, unsigned int rxq_idx); +void netif_rxq_cleanup_phys_lease(struct netdev_rx_queue *rxq); + /* netdev management, shared between various uAPI entry points */ struct netdev_name_node { struct hlist_node hlist;
diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c
index 06ac3bd5507f..6eceda99b662 100644
--- a/net/core/netdev_rx_queue.c
+++ b/net/core/netdev_rx_queue.c@@ -31,6 +31,7 @@ void netdev_rx_queue_unlease(struct netdev_rx_queue *rxq_dst, WRITE_ONCE(rxq_src->lease, NULL); WRITE_ONCE(rxq_dst->lease, NULL); + netif_rxq_cleanup_phys_lease(rxq_src); netdev_put(rxq_src->dev, &rxq_src->lease_tracker); }
@@ -200,24 +201,15 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx) } EXPORT_SYMBOL_NS_GPL(netdev_rx_queue_restart, "NETDEV_INTERNAL"); -int netif_mp_open_rxq(struct net_device *dev, unsigned int rxq_idx, - const struct pp_memory_provider_params *p, - struct netlink_ext_ack *extack) +static int __netif_mp_open_rxq(struct net_device *dev, unsigned int rxq_idx, + const struct pp_memory_provider_params *p, + struct netlink_ext_ack *extack) { const struct netdev_queue_mgmt_ops *qops = dev->queue_mgmt_ops; struct netdev_queue_config qcfg[2]; struct netdev_rx_queue *rxq; int ret; - if (!netdev_need_ops_lock(dev)) - return -EOPNOTSUPP; - - if (rxq_idx >= dev->real_num_rx_queues) { - NL_SET_ERR_MSG(extack, "rx queue index out of range"); - return -ERANGE; - } - rxq_idx = array_index_nospec(rxq_idx, dev->real_num_rx_queues); - if (dev->cfg->hds_config != ETHTOOL_TCP_DATA_SPLIT_ENABLED) { NL_SET_ERR_MSG(extack, "tcp-data-split is disabled"); return -EINVAL;
@@ -264,16 +256,48 @@ int netif_mp_open_rxq(struct net_device *dev, unsigned int rxq_idx, return ret; } -void netif_mp_close_rxq(struct net_device *dev, unsigned int ifq_idx, - const struct pp_memory_provider_params *old_p) +int netif_mp_open_rxq(struct net_device *dev, unsigned int rxq_idx, + const struct pp_memory_provider_params *p, + struct netlink_ext_ack *extack) +{ + struct net_device *orig_dev = dev; + int ret; + + if (!netdev_need_ops_lock(dev)) + return -EOPNOTSUPP; + + if (rxq_idx >= dev->real_num_rx_queues) { + NL_SET_ERR_MSG(extack, "rx queue index out of range"); + return -ERANGE; + } + rxq_idx = array_index_nospec(rxq_idx, dev->real_num_rx_queues); + + if (!netif_rxq_is_leased(dev, rxq_idx)) + return __netif_mp_open_rxq(dev, rxq_idx, p, extack); + + if (!netif_get_rx_queue_lease_locked(&dev, &rxq_idx)) { + NL_SET_ERR_MSG(extack, "rx queue leased to a virtual netdev"); + return -EBUSY; + } + if (!dev->dev.parent) { + NL_SET_ERR_MSG(extack, "rx queue belongs to a virtual netdev"); + ret = -EOPNOTSUPP; + goto out; + } + + ret = __netif_mp_open_rxq(dev, rxq_idx, p, extack); +out: + netif_put_rx_queue_lease_locked(orig_dev, dev); + return ret; +} + +static void __netif_mp_close_rxq(struct net_device *dev, unsigned int ifq_idx, + const struct pp_memory_provider_params *old_p) { struct netdev_queue_config qcfg[2]; struct netdev_rx_queue *rxq; int err; - if (WARN_ON_ONCE(ifq_idx >= dev->real_num_rx_queues)) - return; - rxq = __netif_get_rx_queue(dev, ifq_idx); /* Callers holding a netdev ref may get here after we already
@@ -294,3 +318,38 @@ void netif_mp_close_rxq(struct net_device *dev, unsigned int ifq_idx, err = netdev_rx_queue_reconfig(dev, ifq_idx, &qcfg[0], &qcfg[1]); WARN_ON(err && err != -ENETDOWN); } + +void netif_mp_close_rxq(struct net_device *dev, unsigned int ifq_idx, + const struct pp_memory_provider_params *old_p) +{ + struct net_device *orig_dev = dev; + + if (WARN_ON_ONCE(ifq_idx >= dev->real_num_rx_queues)) + return; + if (!netif_rxq_is_leased(dev, ifq_idx)) + return __netif_mp_close_rxq(dev, ifq_idx, old_p); + + if (WARN_ON_ONCE(!netif_get_rx_queue_lease_locked(&dev, &ifq_idx))) + return; + + __netif_mp_close_rxq(dev, ifq_idx, old_p); + netif_put_rx_queue_lease_locked(orig_dev, dev); +} + +void netif_rxq_cleanup_phys_lease(struct netdev_rx_queue *rxq) +{ + /* If a memory provider was installed on the physical queue via + * the lease, close it now. The memory provider is a property of + * the queue itself, and it was guaranteed to be installed on the + * physical queue via the lease redirection. + * + * After the lease pointers are NULL'ed, net_mp_close_rxq() can + * no longer follow the lease to reach the physical queue. The + * physical device is still running, so the queue is reconfigured + * to replace the memory provider's page pool with a default one. + */ + if (rxq->mp_params.mp_ops) + __netif_mp_close_rxq(rxq->dev, + get_netdev_rx_queue_index(rxq), + &rxq->mp_params); +}
--
2.43.0