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 Fran��ois 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
33#ifndef	_LINUX_UACCESS_H_
34#define	_LINUX_UACCESS_H_
35
36#include <sys/param.h>
37#include <sys/lock.h>
38#include <sys/proc.h>
39
40#include <vm/vm.h>
41#include <vm/vm_extern.h>
42
43#include <linux/compiler.h>
44
45#define	VERIFY_READ	VM_PROT_READ
46#define	VERIFY_WRITE	VM_PROT_WRITE
47
48#define	__get_user(_x, _p) ({					\
49	int __err;						\
50	__typeof(*(_p)) __x;					\
51	__err = linux_copyin((_p), &(__x), sizeof(*(_p)));	\
52	(_x) = __x;						\
53	__err;							\
54})
55
56#define	__put_user(_x, _p) ({				\
57	__typeof(*(_p)) __x = (_x);			\
58	linux_copyout(&(__x), (_p), sizeof(*(_p)));	\
59})
60#define	get_user(_x, _p)	linux_copyin((_p), &(_x), sizeof(*(_p)))
61#define	put_user(_x, _p)	__put_user(_x, _p)
62#define	clear_user(...)		linux_clear_user(__VA_ARGS__)
63
64#if defined(LINUXKPI_VERSION) && LINUXKPI_VERSION >= 50000
65#define	access_ok(a,b)		linux_access_ok(a,b)
66#else
67#define	access_ok(a,b,c)	linux_access_ok(b,c)
68#endif
69
70extern int linux_copyin(const void *uaddr, void *kaddr, size_t len);
71extern int linux_copyout(const void *kaddr, void *uaddr, size_t len);
72extern size_t linux_clear_user(void *uaddr, size_t len);
73extern int linux_access_ok(const void *uaddr, size_t len);
74
75/*
76 * NOTE: Each pagefault_disable() call must have a corresponding
77 * pagefault_enable() call in the same scope. The former creates a new
78 * block and defines a temporary variable, and the latter uses the
79 * temporary variable and closes the block. Failure to balance the
80 * calls will result in a compile-time error.
81 */
82#define	pagefault_disable(void) do {		\
83	int __saved_pflags =			\
84	    vm_fault_disable_pagefaults()
85
86#define	pagefault_enable(void)				\
87	vm_fault_enable_pagefaults(__saved_pflags);	\
88} while (0)
89
90static inline bool
91pagefault_disabled(void)
92{
93	return ((curthread->td_pflags & TDP_NOFAULTING) != 0);
94}
95
96#endif					/* _LINUX_UACCESS_H_ */
97