]>
Commit | Line | Data |
---|---|---|
f5e706ad SR |
1 | /* |
2 | * uaccess.h: User space memore access functions. | |
3 | * | |
4 | * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) | |
5 | * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz) | |
6 | */ | |
7 | #ifndef _ASM_UACCESS_H | |
8 | #define _ASM_UACCESS_H | |
9 | ||
f5e706ad | 10 | #include <linux/compiler.h> |
f5e706ad | 11 | #include <linux/string.h> |
f5e706ad | 12 | |
2c66f623 DM |
13 | #include <asm/processor.h> |
14 | ||
ad6561df RR |
15 | #define ARCH_HAS_SORT_EXTABLE |
16 | #define ARCH_HAS_SEARCH_EXTABLE | |
17 | ||
f5e706ad SR |
18 | /* Sparc is not segmented, however we need to be able to fool access_ok() |
19 | * when doing system calls from kernel mode legitimately. | |
20 | * | |
21 | * "For historical reasons, these macros are grossly misnamed." -Linus | |
22 | */ | |
23 | ||
24 | #define KERNEL_DS ((mm_segment_t) { 0 }) | |
25 | #define USER_DS ((mm_segment_t) { -1 }) | |
26 | ||
f5e706ad SR |
27 | #define get_ds() (KERNEL_DS) |
28 | #define get_fs() (current->thread.current_ds) | |
29 | #define set_fs(val) ((current->thread.current_ds) = (val)) | |
30 | ||
8ccf7b25 | 31 | #define segment_eq(a, b) ((a).seg == (b).seg) |
f5e706ad SR |
32 | |
33 | /* We have there a nice not-mapped page at PAGE_OFFSET - PAGE_SIZE, so that this test | |
34 | * can be fairly lightweight. | |
35 | * No one can read/write anything from userland in the kernel space by setting | |
36 | * large size and address near to PAGE_OFFSET - a fault will break his intentions. | |
37 | */ | |
38 | #define __user_ok(addr, size) ({ (void)(size); (addr) < STACK_TOP; }) | |
db68ce10 | 39 | #define __kernel_ok (uaccess_kernel()) |
8ccf7b25 MT |
40 | #define __access_ok(addr, size) (__user_ok((addr) & get_fs().seg, (size))) |
41 | #define access_ok(type, addr, size) \ | |
f5e706ad SR |
42 | ({ (void)(type); __access_ok((unsigned long)(addr), size); }) |
43 | ||
44 | /* | |
45 | * The exception table consists of pairs of addresses: the first is the | |
46 | * address of an instruction that is allowed to fault, and the second is | |
47 | * the address at which the program should continue. No registers are | |
48 | * modified, so it is entirely up to the continuation code to figure out | |
49 | * what to do. | |
50 | * | |
51 | * All the routines below use bits of fixup code that are out of line | |
52 | * with the main instruction path. This means when everything is well, | |
53 | * we don't even have to jump over them. Further, they do not intrude | |
54 | * on our cache or tlb entries. | |
55 | * | |
56 | * There is a special way how to put a range of potentially faulting | |
57 | * insns (like twenty ldd/std's with now intervening other instructions) | |
58 | * You specify address of first in insn and 0 in fixup and in the next | |
59 | * exception_table_entry you specify last potentially faulting insn + 1 | |
60 | * and in fixup the routine which should handle the fault. | |
61 | * That fixup code will get | |
62 | * (faulting_insn_address - first_insn_in_the_range_address)/4 | |
63 | * in %g2 (ie. index of the faulting instruction in the range). | |
64 | */ | |
65 | ||
66 | struct exception_table_entry | |
67 | { | |
68 | unsigned long insn, fixup; | |
69 | }; | |
70 | ||
71 | /* Returns 0 if exception not found and fixup otherwise. */ | |
f05a6865 | 72 | unsigned long search_extables_range(unsigned long addr, unsigned long *g2); |
f5e706ad | 73 | |
f5e706ad SR |
74 | /* Uh, these should become the main single-value transfer routines.. |
75 | * They automatically use the right size if we just have the right | |
76 | * pointer type.. | |
77 | * | |
78 | * This gets kind of ugly. We want to return _two_ values in "get_user()" | |
79 | * and yet we don't want to do any pointers, because that is too much | |
80 | * of a performance impact. Thus we have a few rather ugly macros here, | |
81 | * and hide all the ugliness from the user. | |
82 | */ | |
8ccf7b25 MT |
83 | #define put_user(x, ptr) ({ \ |
84 | unsigned long __pu_addr = (unsigned long)(ptr); \ | |
85 | __chk_user_ptr(ptr); \ | |
86 | __put_user_check((__typeof__(*(ptr)))(x), __pu_addr, sizeof(*(ptr))); \ | |
87 | }) | |
88 | ||
89 | #define get_user(x, ptr) ({ \ | |
90 | unsigned long __gu_addr = (unsigned long)(ptr); \ | |
91 | __chk_user_ptr(ptr); \ | |
92 | __get_user_check((x), __gu_addr, sizeof(*(ptr)), __typeof__(*(ptr))); \ | |
93 | }) | |
f5e706ad SR |
94 | |
95 | /* | |
96 | * The "__xxx" versions do not do address space checking, useful when | |
97 | * doing multiple accesses to the same area (the user has to do the | |
98 | * checks by hand with "access_ok()") | |
99 | */ | |
8ccf7b25 MT |
100 | #define __put_user(x, ptr) \ |
101 | __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) | |
102 | #define __get_user(x, ptr) \ | |
103 | __get_user_nocheck((x), (ptr), sizeof(*(ptr)), __typeof__(*(ptr))) | |
f5e706ad SR |
104 | |
105 | struct __large_struct { unsigned long buf[100]; }; | |
106 | #define __m(x) ((struct __large_struct __user *)(x)) | |
107 | ||
8ccf7b25 MT |
108 | #define __put_user_check(x, addr, size) ({ \ |
109 | register int __pu_ret; \ | |
110 | if (__access_ok(addr, size)) { \ | |
111 | switch (size) { \ | |
112 | case 1: \ | |
113 | __put_user_asm(x, b, addr, __pu_ret); \ | |
114 | break; \ | |
115 | case 2: \ | |
116 | __put_user_asm(x, h, addr, __pu_ret); \ | |
117 | break; \ | |
118 | case 4: \ | |
119 | __put_user_asm(x, , addr, __pu_ret); \ | |
120 | break; \ | |
121 | case 8: \ | |
122 | __put_user_asm(x, d, addr, __pu_ret); \ | |
123 | break; \ | |
124 | default: \ | |
125 | __pu_ret = __put_user_bad(); \ | |
126 | break; \ | |
127 | } \ | |
128 | } else { \ | |
129 | __pu_ret = -EFAULT; \ | |
130 | } \ | |
131 | __pu_ret; \ | |
132 | }) | |
133 | ||
0795cb1b MT |
134 | #define __put_user_nocheck(x, addr, size) ({ \ |
135 | register int __pu_ret; \ | |
136 | switch (size) { \ | |
137 | case 1: __put_user_asm(x, b, addr, __pu_ret); break; \ | |
138 | case 2: __put_user_asm(x, h, addr, __pu_ret); break; \ | |
139 | case 4: __put_user_asm(x, , addr, __pu_ret); break; \ | |
140 | case 8: __put_user_asm(x, d, addr, __pu_ret); break; \ | |
141 | default: __pu_ret = __put_user_bad(); break; \ | |
8ccf7b25 MT |
142 | } \ |
143 | __pu_ret; \ | |
144 | }) | |
145 | ||
146 | #define __put_user_asm(x, size, addr, ret) \ | |
f5e706ad | 147 | __asm__ __volatile__( \ |
8ccf7b25 MT |
148 | "/* Put user asm, inline. */\n" \ |
149 | "1:\t" "st"#size " %1, %2\n\t" \ | |
150 | "clr %0\n" \ | |
151 | "2:\n\n\t" \ | |
152 | ".section .fixup,#alloc,#execinstr\n\t" \ | |
153 | ".align 4\n" \ | |
154 | "3:\n\t" \ | |
155 | "b 2b\n\t" \ | |
156 | " mov %3, %0\n\t" \ | |
157 | ".previous\n\n\t" \ | |
158 | ".section __ex_table,#alloc\n\t" \ | |
159 | ".align 4\n\t" \ | |
160 | ".word 1b, 3b\n\t" \ | |
161 | ".previous\n\n\t" \ | |
162 | : "=&r" (ret) : "r" (x), "m" (*__m(addr)), \ | |
163 | "i" (-EFAULT)) | |
f5e706ad | 164 | |
f05a6865 | 165 | int __put_user_bad(void); |
f5e706ad | 166 | |
8ccf7b25 MT |
167 | #define __get_user_check(x, addr, size, type) ({ \ |
168 | register int __gu_ret; \ | |
169 | register unsigned long __gu_val; \ | |
170 | if (__access_ok(addr, size)) { \ | |
171 | switch (size) { \ | |
172 | case 1: \ | |
173 | __get_user_asm(__gu_val, ub, addr, __gu_ret); \ | |
174 | break; \ | |
175 | case 2: \ | |
176 | __get_user_asm(__gu_val, uh, addr, __gu_ret); \ | |
177 | break; \ | |
178 | case 4: \ | |
179 | __get_user_asm(__gu_val, , addr, __gu_ret); \ | |
180 | break; \ | |
181 | case 8: \ | |
182 | __get_user_asm(__gu_val, d, addr, __gu_ret); \ | |
183 | break; \ | |
184 | default: \ | |
185 | __gu_val = 0; \ | |
186 | __gu_ret = __get_user_bad(); \ | |
187 | break; \ | |
188 | } \ | |
189 | } else { \ | |
190 | __gu_val = 0; \ | |
191 | __gu_ret = -EFAULT; \ | |
192 | } \ | |
193 | x = (__force type) __gu_val; \ | |
194 | __gu_ret; \ | |
195 | }) | |
196 | ||
0795cb1b MT |
197 | #define __get_user_nocheck(x, addr, size, type) ({ \ |
198 | register int __gu_ret; \ | |
199 | register unsigned long __gu_val; \ | |
200 | switch (size) { \ | |
201 | case 1: __get_user_asm(__gu_val, ub, addr, __gu_ret); break; \ | |
202 | case 2: __get_user_asm(__gu_val, uh, addr, __gu_ret); break; \ | |
203 | case 4: __get_user_asm(__gu_val, , addr, __gu_ret); break; \ | |
204 | case 8: __get_user_asm(__gu_val, d, addr, __gu_ret); break; \ | |
205 | default: \ | |
206 | __gu_val = 0; \ | |
207 | __gu_ret = __get_user_bad(); \ | |
208 | break; \ | |
209 | } \ | |
210 | x = (__force type) __gu_val; \ | |
211 | __gu_ret; \ | |
8ccf7b25 MT |
212 | }) |
213 | ||
8ccf7b25 | 214 | #define __get_user_asm(x, size, addr, ret) \ |
f5e706ad | 215 | __asm__ __volatile__( \ |
8ccf7b25 MT |
216 | "/* Get user asm, inline. */\n" \ |
217 | "1:\t" "ld"#size " %2, %1\n\t" \ | |
218 | "clr %0\n" \ | |
219 | "2:\n\n\t" \ | |
220 | ".section .fixup,#alloc,#execinstr\n\t" \ | |
221 | ".align 4\n" \ | |
222 | "3:\n\t" \ | |
223 | "clr %1\n\t" \ | |
224 | "b 2b\n\t" \ | |
225 | " mov %3, %0\n\n\t" \ | |
226 | ".previous\n\t" \ | |
227 | ".section __ex_table,#alloc\n\t" \ | |
228 | ".align 4\n\t" \ | |
229 | ".word 1b, 3b\n\n\t" \ | |
230 | ".previous\n\t" \ | |
231 | : "=&r" (ret), "=&r" (x) : "m" (*__m(addr)), \ | |
232 | "i" (-EFAULT)) | |
233 | ||
f05a6865 | 234 | int __get_user_bad(void); |
f5e706ad | 235 | |
f05a6865 | 236 | unsigned long __copy_user(void __user *to, const void __user *from, unsigned long size); |
f5e706ad | 237 | |
31af2f36 | 238 | static inline unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n) |
f5e706ad | 239 | { |
f5e706ad SR |
240 | return __copy_user(to, (__force void __user *) from, n); |
241 | } | |
242 | ||
31af2f36 | 243 | static inline unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n) |
f5e706ad SR |
244 | { |
245 | return __copy_user((__force void __user *) to, from, n); | |
246 | } | |
247 | ||
31af2f36 AV |
248 | #define INLINE_COPY_FROM_USER |
249 | #define INLINE_COPY_TO_USER | |
f5e706ad SR |
250 | |
251 | static inline unsigned long __clear_user(void __user *addr, unsigned long size) | |
252 | { | |
253 | unsigned long ret; | |
254 | ||
255 | __asm__ __volatile__ ( | |
256 | ".section __ex_table,#alloc\n\t" | |
257 | ".align 4\n\t" | |
258 | ".word 1f,3\n\t" | |
259 | ".previous\n\t" | |
260 | "mov %2, %%o1\n" | |
261 | "1:\n\t" | |
262 | "call __bzero\n\t" | |
263 | " mov %1, %%o0\n\t" | |
264 | "mov %%o0, %0\n" | |
265 | : "=r" (ret) : "r" (addr), "r" (size) : | |
266 | "o0", "o1", "o2", "o3", "o4", "o5", "o7", | |
267 | "g1", "g2", "g3", "g4", "g5", "g7", "cc"); | |
268 | ||
269 | return ret; | |
270 | } | |
271 | ||
272 | static inline unsigned long clear_user(void __user *addr, unsigned long n) | |
273 | { | |
274 | if (n && __access_ok((unsigned long) addr, n)) | |
275 | return __clear_user(addr, n); | |
276 | else | |
277 | return n; | |
278 | } | |
279 | ||
f05a6865 | 280 | __must_check long strnlen_user(const char __user *str, long n); |
f5e706ad | 281 | |
f5e706ad | 282 | #endif /* _ASM_UACCESS_H */ |