linux/include/linux/if_tap.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_IF_TAP_H_
#define _LINUX_IF_TAP_H_

#include <net/sock.h>
#include <linux/skb_array.h>

struct file;
struct socket;

#if IS_ENABLED(CONFIG_TAP)
struct socket *tap_get_socket(struct file *);
struct ptr_ring *tap_get_ptr_ring(struct file *file);
#else
#include <linux/err.h>
#include <linux/errno.h>
static inline struct socket *tap_get_socket(struct file *f)
{
	return ERR_PTR(-EINVAL);
}
static inline struct ptr_ring *tap_get_ptr_ring(struct file *f)
{
	return ERR_PTR(-EINVAL);
}
#endif /* CONFIG_TAP */

/*
 * Maximum times a tap device can be opened. This can be used to
 * configure the number of receive queue, e.g. for multiqueue virtio.
 */
#define MAX_TAP_QUEUES …

struct tap_queue;

struct tap_dev { … };

/*
 * A tap queue is the central object of tap module, it connects
 * an open character device to virtual interface. There can be
 * multiple queues on one interface, which map back to queues
 * implemented in hardware on the underlying device.
 *
 * tap_proto is used to allocate queues through the sock allocation
 * mechanism.
 *
 */

struct tap_queue { … };

rx_handler_result_t tap_handle_frame(struct sk_buff **pskb);
void tap_del_queues(struct tap_dev *tap);
int tap_get_minor(dev_t major, struct tap_dev *tap);
void tap_free_minor(dev_t major, struct tap_dev *tap);
int tap_queue_resize(struct tap_dev *tap);
int tap_create_cdev(struct cdev *tap_cdev, dev_t *tap_major,
		    const char *device_name, struct module *module);
void tap_destroy_cdev(dev_t major, struct cdev *tap_cdev);

#endif /*_LINUX_IF_TAP_H_*/