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
31#ifndef	_LINUXKPI_LINUX_UACCESS_H_
32#define	_LINUXKPI_LINUX_UACCESS_H_
33
34#include <sys/param.h>
35#include <sys/lock.h>
36#include <sys/proc.h>
37
38#include <vm/vm.h>
39#include <vm/vm_extern.h>
40
41#include <linux/compiler.h>
42
43#define	VERIFY_READ	VM_PROT_READ
44#define	VERIFY_WRITE	VM_PROT_WRITE
45
46#define	__get_user(_x, _p) ({					\
47	int __err;						\
48	__typeof(*(_p)) __x;					\
49	__err = linux_copyin((_p), &(__x), sizeof(*(_p)));	\
50	(_x) = __x;						\
51	__err;							\
52})
53
54#define	__put_user(_x, _p) ({				\
55	__typeof(*(_p)) __x = (_x);			\
56	linux_copyout(&(__x), (_p), sizeof(*(_p)));	\
57})
58#define	get_user(_x, _p)	linux_copyin((_p), &(_x), sizeof(*(_p)))
59#define	put_user(_x, _p)	__put_user(_x, _p)
60#define	clear_user(...)		linux_clear_user(__VA_ARGS__)
61
62#define	access_ok(a,b)		linux_access_ok(a,b)
63
64extern int linux_copyin(const void *uaddr, void *kaddr, size_t len);
65extern int linux_copyout(const void *kaddr, void *uaddr, size_t len);
66extern size_t linux_clear_user(void *uaddr, size_t len);
67extern int linux_access_ok(const void *uaddr, size_t len);
68
69/*
70 * NOTE: Each pagefault_disable() call must have a corresponding
71 * pagefault_enable() call in the same scope. The former creates a new
72 * block and defines a temporary variable, and the latter uses the
73 * temporary variable and closes the block. Failure to balance the
74 * calls will result in a compile-time error.
75 */
76#define	pagefault_disable(void) do {		\
77	int __saved_pflags =			\
78	    vm_fault_disable_pagefaults()
79
80#define	pagefault_enable(void)				\
81	vm_fault_enable_pagefaults(__saved_pflags);	\
82} while (0)
83
84static inline bool
85pagefault_disabled(void)
86{
87	return ((curthread->td_pflags & TDP_NOFAULTING) != 0);
88}
89
90static inline int
91__copy_to_user_inatomic(void __user *to, const void *from, unsigned n)
92{
93
94	return (copyout_nofault(from, to, n) != 0 ? n : 0);
95}
96#define	__copy_to_user_inatomic_nocache(to, from, n)	\
97	__copy_to_user_inatomic((to), (from), (n))
98
99static inline unsigned long
100__copy_from_user_inatomic(void *to, const void __user *from,
101    unsigned long n)
102{
103	/*
104	 * XXXKIB.  Equivalent Linux function is implemented using
105	 * MOVNTI for aligned moves.  For unaligned head and tail,
106	 * normal move is performed.  As such, it is not incorrect, if
107	 * only somewhat slower, to use normal copyin.  All uses
108	 * except shmem_pwrite_fast() have the destination mapped WC.
109	 */
110	return ((copyin_nofault(__DECONST(void *, from), to, n) != 0 ? n : 0));
111}
112#define	__copy_from_user_inatomic_nocache(to, from, n)	\
113	__copy_from_user_inatomic((to), (from), (n))
114
115#endif					/* _LINUXKPI_LINUX_UACCESS_H_ */
116