1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *  Universal TUN/TAP device driver.
4  *  Copyright (C) 1999-2000 Maxim Krasnyansky <max_mk@yahoo.com>
5  */
6 #ifndef __IF_TUN_H
7 #define __IF_TUN_H
8 
9 #include <uapi/linux/if_tun.h>
10 #include <uapi/linux/virtio_net.h>
11 
12 #define TUN_XDP_FLAG 0x1UL
13 
14 #define TUN_MSG_UBUF 1
15 #define TUN_MSG_PTR  2
16 struct tun_msg_ctl {
17 	unsigned short type;
18 	unsigned short num;
19 	void *ptr;
20 };
21 
22 struct tun_xdp_hdr {
23 	int buflen;
24 	struct virtio_net_hdr gso;
25 };
26 
27 #if defined(CONFIG_TUN) || defined(CONFIG_TUN_MODULE)
28 struct socket *tun_get_socket(struct file *);
29 struct ptr_ring *tun_get_tx_ring(struct file *file);
30 
tun_is_xdp_frame(void * ptr)31 static inline bool tun_is_xdp_frame(void *ptr)
32 {
33 	return (unsigned long)ptr & TUN_XDP_FLAG;
34 }
35 
tun_xdp_to_ptr(struct xdp_frame * xdp)36 static inline void *tun_xdp_to_ptr(struct xdp_frame *xdp)
37 {
38 	return (void *)((unsigned long)xdp | TUN_XDP_FLAG);
39 }
40 
tun_ptr_to_xdp(void * ptr)41 static inline struct xdp_frame *tun_ptr_to_xdp(void *ptr)
42 {
43 	return (void *)((unsigned long)ptr & ~TUN_XDP_FLAG);
44 }
45 
46 void tun_ptr_free(void *ptr);
47 #else
48 #include <linux/err.h>
49 #include <linux/errno.h>
50 struct file;
51 struct socket;
52 
tun_get_socket(struct file * f)53 static inline struct socket *tun_get_socket(struct file *f)
54 {
55 	return ERR_PTR(-EINVAL);
56 }
57 
tun_get_tx_ring(struct file * f)58 static inline struct ptr_ring *tun_get_tx_ring(struct file *f)
59 {
60 	return ERR_PTR(-EINVAL);
61 }
62 
tun_is_xdp_frame(void * ptr)63 static inline bool tun_is_xdp_frame(void *ptr)
64 {
65 	return false;
66 }
67 
tun_xdp_to_ptr(struct xdp_frame * xdp)68 static inline void *tun_xdp_to_ptr(struct xdp_frame *xdp)
69 {
70 	return NULL;
71 }
72 
tun_ptr_to_xdp(void * ptr)73 static inline struct xdp_frame *tun_ptr_to_xdp(void *ptr)
74 {
75 	return NULL;
76 }
77 
tun_ptr_free(void * ptr)78 static inline void tun_ptr_free(void *ptr)
79 {
80 }
81 #endif /* CONFIG_TUN */
82 #endif /* __IF_TUN_H */
83