1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _LINUX_IF_TAP_H_ 3#define _LINUX_IF_TAP_H_ 4 5#include <net/sock.h> 6#include <linux/skb_array.h> 7 8struct file; 9struct socket; 10 11#if IS_ENABLED(CONFIG_TAP) 12struct socket *tap_get_socket(struct file *); 13struct ptr_ring *tap_get_ptr_ring(struct file *file); 14#else 15#include <linux/err.h> 16#include <linux/errno.h> 17static inline struct socket *tap_get_socket(struct file *f) 18{ 19 return ERR_PTR(-EINVAL); 20} 21static inline struct ptr_ring *tap_get_ptr_ring(struct file *f) 22{ 23 return ERR_PTR(-EINVAL); 24} 25#endif /* CONFIG_TAP */ 26 27/* 28 * Maximum times a tap device can be opened. This can be used to 29 * configure the number of receive queue, e.g. for multiqueue virtio. 30 */ 31#define MAX_TAP_QUEUES 256 32 33struct tap_queue; 34 35struct tap_dev { 36 struct net_device *dev; 37 u16 flags; 38 /* This array tracks active taps. */ 39 struct tap_queue __rcu *taps[MAX_TAP_QUEUES]; 40 /* This list tracks all taps (both enabled and disabled) */ 41 struct list_head queue_list; 42 int numvtaps; 43 int numqueues; 44 netdev_features_t tap_features; 45 int minor; 46 47 void (*update_features)(struct tap_dev *tap, netdev_features_t features); 48 void (*count_tx_dropped)(struct tap_dev *tap); 49 void (*count_rx_dropped)(struct tap_dev *tap); 50}; 51 52/* 53 * A tap queue is the central object of tap module, it connects 54 * an open character device to virtual interface. There can be 55 * multiple queues on one interface, which map back to queues 56 * implemented in hardware on the underlying device. 57 * 58 * tap_proto is used to allocate queues through the sock allocation 59 * mechanism. 60 * 61 */ 62 63struct tap_queue { 64 struct sock sk; 65 struct socket sock; 66 int vnet_hdr_sz; 67 struct tap_dev __rcu *tap; 68 struct file *file; 69 unsigned int flags; 70 u16 queue_index; 71 bool enabled; 72 struct list_head next; 73 struct ptr_ring ring; 74}; 75 76rx_handler_result_t tap_handle_frame(struct sk_buff **pskb); 77void tap_del_queues(struct tap_dev *tap); 78int tap_get_minor(dev_t major, struct tap_dev *tap); 79void tap_free_minor(dev_t major, struct tap_dev *tap); 80int tap_queue_resize(struct tap_dev *tap); 81int tap_create_cdev(struct cdev *tap_cdev, dev_t *tap_major, 82 const char *device_name, struct module *module); 83void tap_destroy_cdev(dev_t major, struct cdev *tap_cdev); 84 85#endif /*_LINUX_IF_TAP_H_*/ 86