From: David Wei Implement netdev_nl_bind_queue_doit() that creates an rx queue in a virtual netdev and then binds it to an rxq in a real netdev to create a queue pair. Example with ynl client: # ./pyynl/cli.py \ --spec ~/netlink/specs/netdev.yaml \ --do bind-queue \ --json '{"src-ifindex": 4, "src-queue-id": 15, "dst-ifindex": 8, "queue-type": "rx"}' {'dst-queue-id': 1} Note that the netdevice locking order is always from the virtual to the physical device. Signed-off-by: David Wei Co-developed-by: Daniel Borkmann Signed-off-by: Daniel Borkmann --- include/net/netdev_queues.h | 5 ++ include/net/netdev_rx_queue.h | 36 ++++++++- net/core/netdev-genl.c | 141 +++++++++++++++++++++++++++++++++- net/core/netdev_rx_queue.c | 59 ++++++++++++++ 4 files changed, 238 insertions(+), 3 deletions(-) diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h index cd00e0406cf4..286d5edce07d 100644 --- a/include/net/netdev_queues.h +++ b/include/net/netdev_queues.h @@ -130,6 +130,10 @@ void netdev_stat_queue_sum(struct net_device *netdev, * @ndo_queue_get_dma_dev: Get dma device for zero-copy operations to be used * for this queue. Return NULL on error. * + * @ndo_queue_create: Create a new RX queue which can be bound to another queue. + * Ops on this queue are redirected to the peer queue e.g. + * when opening a memory provider. + * * Note that @ndo_queue_mem_alloc and @ndo_queue_mem_free may be called while * the interface is closed. @ndo_queue_start and @ndo_queue_stop will only * be called for an interface which is open. @@ -149,6 +153,7 @@ struct netdev_queue_mgmt_ops { int idx); struct device * (*ndo_queue_get_dma_dev)(struct net_device *dev, int idx); + int (*ndo_queue_create)(struct net_device *dev); }; bool netif_rxq_has_unreadable_mp(struct net_device *dev, int idx); diff --git a/include/net/netdev_rx_queue.h b/include/net/netdev_rx_queue.h index 8cdcd138b33f..db3ef94c0744 100644 --- a/include/net/netdev_rx_queue.h +++ b/include/net/netdev_rx_queue.h @@ -28,6 +28,7 @@ struct netdev_rx_queue { #endif struct napi_struct *napi; struct pp_memory_provider_params mp_params; + struct netdev_rx_queue *peer; } ____cacheline_aligned_in_smp; /* @@ -56,6 +57,37 @@ get_netdev_rx_queue_index(struct netdev_rx_queue *queue) return index; } -int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq); +static inline void __netdev_rx_queue_peer(struct netdev_rx_queue *src_rxq, + struct netdev_rx_queue *dst_rxq) +{ + src_rxq->peer = dst_rxq; + dst_rxq->peer = src_rxq; +} -#endif +static inline void __netdev_rx_queue_unpeer(struct netdev_rx_queue *src_rxq, + struct netdev_rx_queue *dst_rxq) +{ + src_rxq->peer = NULL; + dst_rxq->peer = NULL; +} + +static inline bool netdev_rx_queue_peered(struct net_device *dev, + u16 queue_id) +{ + if (queue_id < dev->real_num_rx_queues) + return dev->_rx[queue_id].peer; + return false; +} + +void netdev_rx_queue_peer(struct net_device *src_dev, + struct netdev_rx_queue *src_rxq, + struct netdev_rx_queue *dst_rxq); +void netdev_rx_queue_unpeer(struct net_device *src_dev, + struct netdev_rx_queue *src_rxq, + struct netdev_rx_queue *dst_rxq); +int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq); +struct netdev_rx_queue * +netif_get_rx_queue_peer_locked(struct net_device **dev, + unsigned int *rxq_idx, + bool *needs_unlock); +#endif /* _LINUX_NETDEV_RX_QUEUE_H */ diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c index ce1018ea390f..579469abac8c 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -1122,7 +1122,146 @@ int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info) int netdev_nl_bind_queue_doit(struct sk_buff *skb, struct genl_info *info) { - return -EOPNOTSUPP; + u32 src_ifidx, src_qid, dst_ifidx, dst_qid, q_type; + struct netdev_rx_queue *src_rxq, *dst_rxq, *tmp_rxq; + struct net_device *src_dev, *dst_dev; + struct sk_buff *rsp; + int err = 0; + void *hdr; + + if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_PAIR_QUEUE_TYPE) || + GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_PAIR_SRC_IFINDEX) || + GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_PAIR_SRC_QUEUE_ID) || + GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_PAIR_DST_IFINDEX)) + return -EINVAL; + + src_ifidx = nla_get_u32(info->attrs[NETDEV_A_QUEUE_PAIR_SRC_IFINDEX]); + src_qid = nla_get_u32(info->attrs[NETDEV_A_QUEUE_PAIR_SRC_QUEUE_ID]); + dst_ifidx = nla_get_u32(info->attrs[NETDEV_A_QUEUE_PAIR_DST_IFINDEX]); + q_type = nla_get_u32(info->attrs[NETDEV_A_QUEUE_PAIR_QUEUE_TYPE]); + + if (q_type != NETDEV_QUEUE_TYPE_RX) { + NL_SET_ERR_MSG(info->extack, "Only binding of RX queue supported"); + return -EOPNOTSUPP; + } + if (dst_ifidx == src_ifidx) { + NL_SET_ERR_MSG(info->extack, + "Destination driver cannot be same as source driver"); + return -EOPNOTSUPP; + } + + rsp = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!rsp) + return -ENOMEM; + + hdr = genlmsg_iput(rsp, info); + if (!hdr) { + err = -EMSGSIZE; + goto err_genlmsg_free; + } + + /* Locking order is always from the virtual to the physical device + * since this is also the same order when applications open the + * memory provider later on. + */ + dst_dev = netdev_get_by_index_lock(genl_info_net(info), dst_ifidx); + if (!dst_dev) { + err = -ENODEV; + goto err_genlmsg_free; + } + if (dst_dev->dev.parent) { + err = -EOPNOTSUPP; + NL_SET_ERR_MSG(info->extack, + "Destination device is not a virtual device"); + goto err_unlock_dst_dev; + } + if (!dst_dev->queue_mgmt_ops || + !dst_dev->queue_mgmt_ops->ndo_queue_create) { + err = -EOPNOTSUPP; + NL_SET_ERR_MSG(info->extack, + "Destination driver does not support queue management operations"); + goto err_unlock_dst_dev; + } + if (dst_dev->real_num_rx_queues < 1) { + err = -EOPNOTSUPP; + NL_SET_ERR_MSG(info->extack, + "Destination device must have at least one real RX queue"); + goto err_unlock_dst_dev; + } + + src_dev = netdev_get_by_index_lock(genl_info_net(info), src_ifidx); + if (!src_dev) { + err = -ENODEV; + goto err_unlock_dst_dev; + } + if (!src_dev->dev.parent) { + err = -EOPNOTSUPP; + NL_SET_ERR_MSG(info->extack, + "Source device is a virtual device"); + goto err_unlock_src_dev; + } + if (!netif_device_present(src_dev)) { + err = -ENODEV; + NL_SET_ERR_MSG(info->extack, + "Source device has been removed from the system"); + goto err_unlock_src_dev; + } + if (!src_dev->queue_mgmt_ops) { + err = -EOPNOTSUPP; + NL_SET_ERR_MSG(info->extack, + "Source driver does not support queue management operations"); + goto err_unlock_src_dev; + } + if (src_qid >= src_dev->num_rx_queues) { + err = -ERANGE; + NL_SET_ERR_MSG(info->extack, + "Source device queue is out of range"); + goto err_unlock_src_dev; + } + + src_rxq = __netif_get_rx_queue(src_dev, src_qid); + if (src_rxq->peer) { + err = -EBUSY; + NL_SET_ERR_MSG(info->extack, + "Source device queue is already bound"); + goto err_unlock_src_dev; + } + + tmp_rxq = __netif_get_rx_queue(dst_dev, dst_dev->real_num_rx_queues - 1); + if (tmp_rxq->peer && tmp_rxq->peer->dev != src_dev) { + err = -EOPNOTSUPP; + NL_SET_ERR_MSG(info->extack, + "Binding multiple queues from difference source devices not supported"); + goto err_unlock_src_dev; + } + + err = dst_dev->queue_mgmt_ops->ndo_queue_create(dst_dev); + if (err <= 0) { + NL_SET_ERR_MSG(info->extack, + "Destination device is unable to create a new queue"); + goto err_unlock_src_dev; + } + + dst_qid = err - 1; + dst_rxq = __netif_get_rx_queue(dst_dev, dst_qid); + + netdev_rx_queue_peer(src_dev, src_rxq, dst_rxq); + + nla_put_u32(rsp, NETDEV_A_QUEUE_PAIR_DST_QUEUE_ID, dst_qid); + genlmsg_end(rsp, hdr); + + netdev_unlock(src_dev); + netdev_unlock(dst_dev); + + return genlmsg_reply(rsp, info); + +err_unlock_src_dev: + netdev_unlock(src_dev); +err_unlock_dst_dev: + netdev_unlock(dst_dev); +err_genlmsg_free: + nlmsg_free(rsp); + return err; } void netdev_nl_sock_priv_init(struct netdev_nl_sock *priv) diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c index c7d9341b7630..85cf1b3749ee 100644 --- a/net/core/netdev_rx_queue.c +++ b/net/core/netdev_rx_queue.c @@ -18,6 +18,65 @@ bool netif_rxq_has_unreadable_mp(struct net_device *dev, int idx) } EXPORT_SYMBOL(netif_rxq_has_unreadable_mp); +void netdev_rx_queue_peer(struct net_device *src_dev, + struct netdev_rx_queue *src_rxq, + struct netdev_rx_queue *dst_rxq) +{ + netdev_assert_locked(src_dev); + netdev_assert_locked(dst_rxq->dev); + + netdev_hold(src_dev, &src_rxq->dev_tracker, GFP_KERNEL); + __netdev_rx_queue_peer(src_rxq, dst_rxq); +} + +void netdev_rx_queue_unpeer(struct net_device *src_dev, + struct netdev_rx_queue *src_rxq, + struct netdev_rx_queue *dst_rxq) +{ + WARN_ON_ONCE(READ_ONCE(dst_rxq->dev->reg_state) != NETREG_UNREGISTERING); + netdev_assert_locked(src_dev); + + __netdev_rx_queue_unpeer(src_rxq, dst_rxq); + netdev_put(src_dev, &src_rxq->dev_tracker); +} + +static struct netdev_rx_queue * +__netif_get_rx_queue_peer(struct net_device **dev, unsigned int *rxq_idx, + bool virt_to_phys_only) +{ + struct net_device *req_dev = *dev; + struct netdev_rx_queue *rxq = __netif_get_rx_queue(req_dev, *rxq_idx); + + if (rxq->peer) { + if (virt_to_phys_only && + req_dev->dev.parent) + return NULL; + rxq = rxq->peer; + *rxq_idx = get_netdev_rx_queue_index(rxq); + *dev = rxq->dev; + } + return rxq; +} + +struct netdev_rx_queue * +netif_get_rx_queue_peer_locked(struct net_device **dev, unsigned int *rxq_idx, + bool *needs_unlock) +{ + struct net_device *req_dev = *dev; + struct netdev_rx_queue *rxq; + + /* Locking order is always from the virtual to the physical device + * see netdev_nl_bind_queue_doit(). + */ + netdev_assert_locked(req_dev); + rxq = __netif_get_rx_queue_peer(dev, rxq_idx, true); + if (rxq && req_dev != *dev) { + *needs_unlock = true; + netdev_lock(*dev); + } + return rxq; +} + int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx) { struct netdev_rx_queue *rxq = __netif_get_rx_queue(dev, rxq_idx); -- 2.43.0