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1965aae3 PA |
1 | #ifndef _ASM_X86_UACCESS_32_H |
2 | #define _ASM_X86_UACCESS_32_H | |
1da177e4 LT |
3 | |
4 | /* | |
5 | * User space memory access functions | |
6 | */ | |
1da177e4 LT |
7 | #include <linux/errno.h> |
8 | #include <linux/thread_info.h> | |
1da177e4 | 9 | #include <linux/string.h> |
14e6d17d | 10 | #include <asm/asm.h> |
1da177e4 LT |
11 | #include <asm/page.h> |
12 | ||
b1fcec7f JP |
13 | unsigned long __must_check __copy_to_user_ll |
14 | (void __user *to, const void *from, unsigned long n); | |
15 | unsigned long __must_check __copy_from_user_ll | |
16 | (void *to, const void __user *from, unsigned long n); | |
17 | unsigned long __must_check __copy_from_user_ll_nozero | |
18 | (void *to, const void __user *from, unsigned long n); | |
19 | unsigned long __must_check __copy_from_user_ll_nocache | |
20 | (void *to, const void __user *from, unsigned long n); | |
21 | unsigned long __must_check __copy_from_user_ll_nocache_nozero | |
22 | (void *to, const void __user *from, unsigned long n); | |
1da177e4 | 23 | |
6d1c4261 AK |
24 | /** |
25 | * __copy_to_user_inatomic: - Copy a block of data into user space, with less checking. | |
26 | * @to: Destination address, in user space. | |
27 | * @from: Source address, in kernel space. | |
28 | * @n: Number of bytes to copy. | |
29 | * | |
30 | * Context: User context only. | |
31 | * | |
32 | * Copy data from kernel space to user space. Caller must check | |
33 | * the specified block with access_ok() before calling this function. | |
34 | * The caller should also make sure he pins the user space address | |
4fe48782 | 35 | * so that we don't result in page fault and sleep. |
1da177e4 | 36 | */ |
652050ae | 37 | static __always_inline unsigned long __must_check |
1da177e4 LT |
38 | __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n) |
39 | { | |
1da177e4 LT |
40 | return __copy_to_user_ll(to, from, n); |
41 | } | |
42 | ||
1da177e4 | 43 | /** |
9c7fff6e RD |
44 | * __copy_to_user: - Copy a block of data into user space, with less checking. |
45 | * @to: Destination address, in user space. | |
46 | * @from: Source address, in kernel space. | |
1da177e4 LT |
47 | * @n: Number of bytes to copy. |
48 | * | |
b3c395ef DH |
49 | * Context: User context only. This function may sleep if pagefaults are |
50 | * enabled. | |
1da177e4 | 51 | * |
9c7fff6e | 52 | * Copy data from kernel space to user space. Caller must check |
1da177e4 LT |
53 | * the specified block with access_ok() before calling this function. |
54 | * | |
55 | * Returns number of bytes that could not be copied. | |
56 | * On success, this will be zero. | |
1da177e4 | 57 | */ |
9c7fff6e RD |
58 | static __always_inline unsigned long __must_check |
59 | __copy_to_user(void __user *to, const void *from, unsigned long n) | |
60 | { | |
3ee1afa3 | 61 | might_fault(); |
c10d38dd | 62 | return __copy_to_user_inatomic(to, from, n); |
9c7fff6e RD |
63 | } |
64 | ||
652050ae | 65 | static __always_inline unsigned long |
1da177e4 LT |
66 | __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n) |
67 | { | |
7c12d811 N |
68 | return __copy_from_user_ll_nozero(to, from, n); |
69 | } | |
9c7fff6e RD |
70 | |
71 | /** | |
72 | * __copy_from_user: - Copy a block of data from user space, with less checking. | |
73 | * @to: Destination address, in kernel space. | |
74 | * @from: Source address, in user space. | |
75 | * @n: Number of bytes to copy. | |
76 | * | |
b3c395ef DH |
77 | * Context: User context only. This function may sleep if pagefaults are |
78 | * enabled. | |
9c7fff6e RD |
79 | * |
80 | * Copy data from user space to kernel space. Caller must check | |
81 | * the specified block with access_ok() before calling this function. | |
82 | * | |
83 | * Returns number of bytes that could not be copied. | |
84 | * On success, this will be zero. | |
85 | * | |
86 | * If some data could not be copied, this function will pad the copied | |
87 | * data to the requested size using zero bytes. | |
88 | * | |
89 | * An alternate version - __copy_from_user_inatomic() - may be called from | |
90 | * atomic context and will fail rather than sleep. In this case the | |
91 | * uncopied bytes will *NOT* be padded with zeros. See fs/filemap.h | |
92 | * for explanation of why this is needed. | |
93 | */ | |
7c12d811 N |
94 | static __always_inline unsigned long |
95 | __copy_from_user(void *to, const void __user *from, unsigned long n) | |
96 | { | |
3ee1afa3 | 97 | might_fault(); |
1da177e4 LT |
98 | if (__builtin_constant_p(n)) { |
99 | unsigned long ret; | |
100 | ||
101 | switch (n) { | |
102 | case 1: | |
de9e478b | 103 | __uaccess_begin(); |
1da177e4 | 104 | __get_user_size(*(u8 *)to, from, 1, ret, 1); |
de9e478b | 105 | __uaccess_end(); |
1da177e4 LT |
106 | return ret; |
107 | case 2: | |
de9e478b | 108 | __uaccess_begin(); |
1da177e4 | 109 | __get_user_size(*(u16 *)to, from, 2, ret, 2); |
de9e478b | 110 | __uaccess_end(); |
1da177e4 LT |
111 | return ret; |
112 | case 4: | |
de9e478b | 113 | __uaccess_begin(); |
1da177e4 | 114 | __get_user_size(*(u32 *)to, from, 4, ret, 4); |
de9e478b | 115 | __uaccess_end(); |
1da177e4 LT |
116 | return ret; |
117 | } | |
118 | } | |
119 | return __copy_from_user_ll(to, from, n); | |
120 | } | |
121 | ||
7c12d811 | 122 | static __always_inline unsigned long __copy_from_user_nocache(void *to, |
c22ce143 HY |
123 | const void __user *from, unsigned long n) |
124 | { | |
3ee1afa3 | 125 | might_fault(); |
c22ce143 HY |
126 | if (__builtin_constant_p(n)) { |
127 | unsigned long ret; | |
128 | ||
129 | switch (n) { | |
130 | case 1: | |
de9e478b | 131 | __uaccess_begin(); |
c22ce143 | 132 | __get_user_size(*(u8 *)to, from, 1, ret, 1); |
de9e478b | 133 | __uaccess_end(); |
c22ce143 HY |
134 | return ret; |
135 | case 2: | |
de9e478b | 136 | __uaccess_begin(); |
c22ce143 | 137 | __get_user_size(*(u16 *)to, from, 2, ret, 2); |
de9e478b | 138 | __uaccess_end(); |
c22ce143 HY |
139 | return ret; |
140 | case 4: | |
de9e478b | 141 | __uaccess_begin(); |
c22ce143 | 142 | __get_user_size(*(u32 *)to, from, 4, ret, 4); |
de9e478b | 143 | __uaccess_end(); |
c22ce143 HY |
144 | return ret; |
145 | } | |
146 | } | |
147 | return __copy_from_user_ll_nocache(to, from, n); | |
148 | } | |
149 | ||
652050ae | 150 | static __always_inline unsigned long |
b1fcec7f JP |
151 | __copy_from_user_inatomic_nocache(void *to, const void __user *from, |
152 | unsigned long n) | |
1da177e4 | 153 | { |
7c12d811 | 154 | return __copy_from_user_ll_nocache_nozero(to, from, n); |
c22ce143 HY |
155 | } |
156 | ||
1965aae3 | 157 | #endif /* _ASM_X86_UACCESS_32_H */ |