1 // SPDX-License-Identifier: GPL-2.0-or-later 2 3 #include <net/netdev_queues.h> 4 #include <net/netdev_rx_queue.h> 5 #include <net/xdp_sock_drv.h> 6 7 #include "dev.h" 8 9 static struct device * 10 __netdev_queue_get_dma_dev(struct net_device *dev, unsigned int idx) 11 { 12 const struct netdev_queue_mgmt_ops *queue_ops = dev->queue_mgmt_ops; 13 struct device *dma_dev; 14 15 if (queue_ops && queue_ops->ndo_queue_get_dma_dev) 16 dma_dev = queue_ops->ndo_queue_get_dma_dev(dev, idx); 17 else 18 dma_dev = dev->dev.parent; 19 20 return dma_dev && dma_dev->dma_mask ? dma_dev : NULL; 21 } 22 23 /** 24 * netdev_queue_get_dma_dev() - get dma device for zero-copy operations 25 * @dev: net_device 26 * @idx: queue index 27 * @type: queue type (RX or TX) 28 * 29 * Get dma device for zero-copy operations to be used for this queue. If 30 * the queue is an RX queue leased from a physical queue, we retrieve the 31 * physical queue's dma device. When the dma device is not available or 32 * valid, the function will return NULL. 33 * 34 * Return: Device or NULL on error 35 */ 36 struct device *netdev_queue_get_dma_dev(struct net_device *dev, 37 unsigned int idx, 38 enum netdev_queue_type type) 39 { 40 struct netdev_rx_queue *hw_rxq; 41 struct device *dma_dev; 42 43 netdev_ops_assert_locked(dev); 44 45 /* Only RX side supports queue leasing today. */ 46 if (type != NETDEV_QUEUE_TYPE_RX || !netif_rxq_is_leased(dev, idx)) 47 return __netdev_queue_get_dma_dev(dev, idx); 48 if (!netif_is_queue_leasee(dev)) 49 return NULL; 50 51 hw_rxq = __netif_get_rx_queue(dev, idx)->lease; 52 53 netdev_lock(hw_rxq->dev); 54 idx = get_netdev_rx_queue_index(hw_rxq); 55 dma_dev = __netdev_queue_get_dma_dev(hw_rxq->dev, idx); 56 netdev_unlock(hw_rxq->dev); 57 58 return dma_dev; 59 } 60 61 bool netdev_can_create_queue(const struct net_device *dev, 62 struct netlink_ext_ack *extack) 63 { 64 if (dev->dev.parent) { 65 NL_SET_ERR_MSG(extack, "Device is not a virtual device"); 66 return false; 67 } 68 if (!dev->queue_mgmt_ops || 69 !dev->queue_mgmt_ops->ndo_queue_create) { 70 NL_SET_ERR_MSG(extack, "Device does not support queue creation"); 71 return false; 72 } 73 if (dev->real_num_rx_queues < 1 || 74 dev->real_num_tx_queues < 1) { 75 NL_SET_ERR_MSG(extack, "Device must have at least one real queue"); 76 return false; 77 } 78 return true; 79 } 80 81 bool netdev_can_lease_queue(const struct net_device *dev, 82 struct netlink_ext_ack *extack) 83 { 84 if (!dev->dev.parent) { 85 NL_SET_ERR_MSG(extack, "Lease device is a virtual device"); 86 return false; 87 } 88 if (!netif_device_present(dev)) { 89 NL_SET_ERR_MSG(extack, "Lease device has been removed from the system"); 90 return false; 91 } 92 if (!dev->queue_mgmt_ops) { 93 NL_SET_ERR_MSG(extack, "Lease device does not support queue management operations"); 94 return false; 95 } 96 return true; 97 } 98 99 bool netdev_queue_busy(struct net_device *dev, unsigned int idx, 100 enum netdev_queue_type type, 101 struct netlink_ext_ack *extack) 102 { 103 if (xsk_get_pool_from_qid(dev, idx)) { 104 NL_SET_ERR_MSG(extack, "Device queue in use by AF_XDP"); 105 return true; 106 } 107 if (type == NETDEV_QUEUE_TYPE_TX) 108 return false; 109 if (netif_rxq_is_leased(dev, idx)) { 110 NL_SET_ERR_MSG(extack, "Device queue in use due to queue leasing"); 111 return true; 112 } 113 if (netif_rxq_has_mp(dev, idx)) { 114 NL_SET_ERR_MSG(extack, "Device queue in use by memory provider"); 115 return true; 116 } 117 return false; 118 } 119