xref: /freebsd/sys/compat/linuxkpi/common/include/linux/uaccess.h (revision 076ad2f836d5f49dc1375f1677335a48fe0d4b82)
1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
6  * Copyright (c) 2015 François Tigeot
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice unmodified, this list of conditions, and the following
14  *    disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 #ifndef	_LINUX_UACCESS_H_
33 #define	_LINUX_UACCESS_H_
34 
35 #include <linux/compiler.h>
36 
37 #define	__get_user(_x, _p) ({					\
38 	int __err;						\
39 	__typeof(*(_p)) __x;					\
40 	__err = linux_copyin((_p), &(__x), sizeof(*(_p)));	\
41 	(_x) = __x;						\
42 	__err;							\
43 })
44 
45 #define	__put_user(_x, _p) ({				\
46 	__typeof(*(_p)) __x = (_x);			\
47 	linux_copyout(&(__x), (_p), sizeof(*(_p)));	\
48 })
49 #define	get_user(_x, _p)	linux_copyin((_p), &(_x), sizeof(*(_p)))
50 #define	put_user(_x, _p)	linux_copyout(&(_x), (_p), sizeof(*(_p)))
51 
52 extern int linux_copyin(const void *uaddr, void *kaddr, size_t len);
53 extern int linux_copyout(const void *kaddr, void *uaddr, size_t len);
54 
55 /*
56  * NOTE: The returned value from pagefault_disable() must be stored
57  * and passed to pagefault_enable(). Else possible recursion on the
58  * state can be lost.
59  */
60 static inline int __must_check
61 pagefault_disable(void)
62 {
63 	return (vm_fault_disable_pagefaults());
64 }
65 
66 static inline void
67 pagefault_enable(int save)
68 {
69 	vm_fault_enable_pagefaults(save);
70 }
71 
72 #endif	/* _LINUX_UACCESS_H_ */
73