LXR linux/include/linux/if

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