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1/*
2 * arch/arm/include/asm/uaccess.h
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8#ifndef _ASMARM_UACCESS_H
9#define _ASMARM_UACCESS_H
10
11/*
12 * User space memory access functions
13 */
14#include <linux/string.h>
15#include <linux/thread_info.h>
16#include <asm/errno.h>
17#include <asm/memory.h>
18#include <asm/domain.h>
19#include <asm/unified.h>
20#include <asm/compiler.h>
21
22#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
23#include <asm-generic/uaccess-unaligned.h>
24#else
25#define __get_user_unaligned __get_user
26#define __put_user_unaligned __put_user
27#endif
28
29#define VERIFY_READ 0
30#define VERIFY_WRITE 1
31
32/*
33 * The exception table consists of pairs of addresses: the first is the
34 * address of an instruction that is allowed to fault, and the second is
35 * the address at which the program should continue. No registers are
36 * modified, so it is entirely up to the continuation code to figure out
37 * what to do.
38 *
39 * All the routines below use bits of fixup code that are out of line
40 * with the main instruction path. This means when everything is well,
41 * we don't even have to jump over them. Further, they do not intrude
42 * on our cache or tlb entries.
43 */
44
45struct exception_table_entry
46{
47 unsigned long insn, fixup;
48};
49
50extern int fixup_exception(struct pt_regs *regs);
51
52/*
53 * These two are intentionally not defined anywhere - if the kernel
54 * code generates any references to them, that's a bug.
55 */
56extern int __get_user_bad(void);
57extern int __put_user_bad(void);
58
59/*
60 * Note that this is actually 0x1,0000,0000
61 */
62#define KERNEL_DS 0x00000000
63#define get_ds() (KERNEL_DS)
64
65#ifdef CONFIG_MMU
66
67#define USER_DS TASK_SIZE
68#define get_fs() (current_thread_info()->addr_limit)
69
70static inline void set_fs(mm_segment_t fs)
71{
72 current_thread_info()->addr_limit = fs;
73 modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
74}
75
76#define segment_eq(a,b) ((a) == (b))
77
78#define __addr_ok(addr) ({ \
79 unsigned long flag; \
80 __asm__("cmp %2, %0; movlo %0, #0" \
81 : "=&r" (flag) \
82 : "0" (current_thread_info()->addr_limit), "r" (addr) \
83 : "cc"); \
84 (flag == 0); })
85
86/* We use 33-bit arithmetic here... */
87#define __range_ok(addr,size) ({ \
88 unsigned long flag, roksum; \
89 __chk_user_ptr(addr); \
90 __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
91 : "=&r" (flag), "=&r" (roksum) \
92 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
93 : "cc"); \
94 flag; })
95
96/*
97 * Single-value transfer routines. They automatically use the right
98 * size if we just have the right pointer type. Note that the functions
99 * which read from user space (*get_*) need to take care not to leak
100 * kernel data even if the calling code is buggy and fails to check
101 * the return value. This means zeroing out the destination variable
102 * or buffer on error. Normally this is done out of line by the
103 * fixup code, but there are a few places where it intrudes on the
104 * main code path. When we only write to user space, there is no
105 * problem.
106 */
107extern int __get_user_1(void *);
108extern int __get_user_2(void *);
109extern int __get_user_4(void *);
110
111#define __GUP_CLOBBER_1 "lr", "cc"
112#ifdef CONFIG_CPU_USE_DOMAINS
113#define __GUP_CLOBBER_2 "ip", "lr", "cc"
114#else
115#define __GUP_CLOBBER_2 "lr", "cc"
116#endif
117#define __GUP_CLOBBER_4 "lr", "cc"
118
119#define __get_user_x(__r2,__p,__e,__l,__s) \
120 __asm__ __volatile__ ( \
121 __asmeq("%0", "r0") __asmeq("%1", "r2") \
122 __asmeq("%3", "r1") \
123 "bl __get_user_" #__s \
124 : "=&r" (__e), "=r" (__r2) \
125 : "0" (__p), "r" (__l) \
126 : __GUP_CLOBBER_##__s)
127
128#define __get_user_check(x,p) \
129 ({ \
130 unsigned long __limit = current_thread_info()->addr_limit - 1; \
131 register const typeof(*(p)) __user *__p asm("r0") = (p);\
132 register unsigned long __r2 asm("r2"); \
133 register unsigned long __l asm("r1") = __limit; \
134 register int __e asm("r0"); \
135 switch (sizeof(*(__p))) { \
136 case 1: \
137 __get_user_x(__r2, __p, __e, __l, 1); \
138 break; \
139 case 2: \
140 __get_user_x(__r2, __p, __e, __l, 2); \
141 break; \
142 case 4: \
143 __get_user_x(__r2, __p, __e, __l, 4); \
144 break; \
145 default: __e = __get_user_bad(); break; \
146 } \
147 x = (typeof(*(p))) __r2; \
148 __e; \
149 })
150
151#define get_user(x,p) \
152 ({ \
153 might_fault(); \
154 __get_user_check(x,p); \
155 })
156
157extern int __put_user_1(void *, unsigned int);
158extern int __put_user_2(void *, unsigned int);
159extern int __put_user_4(void *, unsigned int);
160extern int __put_user_8(void *, unsigned long long);
161
162#define __put_user_x(__r2,__p,__e,__l,__s) \
163 __asm__ __volatile__ ( \
164 __asmeq("%0", "r0") __asmeq("%2", "r2") \
165 __asmeq("%3", "r1") \
166 "bl __put_user_" #__s \
167 : "=&r" (__e) \
168 : "0" (__p), "r" (__r2), "r" (__l) \
169 : "ip", "lr", "cc")
170
171#define __put_user_check(x,p) \
172 ({ \
173 unsigned long __limit = current_thread_info()->addr_limit - 1; \
174 const typeof(*(p)) __user *__tmp_p = (p); \
175 register const typeof(*(p)) __r2 asm("r2") = (x); \
176 register const typeof(*(p)) __user *__p asm("r0") = __tmp_p; \
177 register unsigned long __l asm("r1") = __limit; \
178 register int __e asm("r0"); \
179 switch (sizeof(*(__p))) { \
180 case 1: \
181 __put_user_x(__r2, __p, __e, __l, 1); \
182 break; \
183 case 2: \
184 __put_user_x(__r2, __p, __e, __l, 2); \
185 break; \
186 case 4: \
187 __put_user_x(__r2, __p, __e, __l, 4); \
188 break; \
189 case 8: \
190 __put_user_x(__r2, __p, __e, __l, 8); \
191 break; \
192 default: __e = __put_user_bad(); break; \
193 } \
194 __e; \
195 })
196
197#define put_user(x,p) \
198 ({ \
199 might_fault(); \
200 __put_user_check(x,p); \
201 })
202
203#else /* CONFIG_MMU */
204
205/*
206 * uClinux has only one addr space, so has simplified address limits.
207 */
208#define USER_DS KERNEL_DS
209
210#define segment_eq(a,b) (1)
211#define __addr_ok(addr) ((void)(addr),1)
212#define __range_ok(addr,size) ((void)(addr),0)
213#define get_fs() (KERNEL_DS)
214
215static inline void set_fs(mm_segment_t fs)
216{
217}
218
219#define get_user(x,p) __get_user(x,p)
220#define put_user(x,p) __put_user(x,p)
221
222#endif /* CONFIG_MMU */
223
224#define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
225
226#define user_addr_max() \
227 (segment_eq(get_fs(), USER_DS) ? TASK_SIZE : ~0UL)
228
229/*
230 * The "__xxx" versions of the user access functions do not verify the
231 * address space - it must have been done previously with a separate
232 * "access_ok()" call.
233 *
234 * The "xxx_error" versions set the third argument to EFAULT if an
235 * error occurs, and leave it unchanged on success. Note that these
236 * versions are void (ie, don't return a value as such).
237 */
238#define __get_user(x,ptr) \
239({ \
240 long __gu_err = 0; \
241 __get_user_err((x),(ptr),__gu_err); \
242 __gu_err; \
243})
244
245#define __get_user_error(x,ptr,err) \
246({ \
247 __get_user_err((x),(ptr),err); \
248 (void) 0; \
249})
250
251#define __get_user_err(x,ptr,err) \
252do { \
253 unsigned long __gu_addr = (unsigned long)(ptr); \
254 unsigned long __gu_val; \
255 __chk_user_ptr(ptr); \
256 might_fault(); \
257 switch (sizeof(*(ptr))) { \
258 case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \
259 case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \
260 case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \
261 default: (__gu_val) = __get_user_bad(); \
262 } \
263 (x) = (__typeof__(*(ptr)))__gu_val; \
264} while (0)
265
266#define __get_user_asm_byte(x,addr,err) \
267 __asm__ __volatile__( \
268 "1: " TUSER(ldrb) " %1,[%2],#0\n" \
269 "2:\n" \
270 " .pushsection .fixup,\"ax\"\n" \
271 " .align 2\n" \
272 "3: mov %0, %3\n" \
273 " mov %1, #0\n" \
274 " b 2b\n" \
275 " .popsection\n" \
276 " .pushsection __ex_table,\"a\"\n" \
277 " .align 3\n" \
278 " .long 1b, 3b\n" \
279 " .popsection" \
280 : "+r" (err), "=&r" (x) \
281 : "r" (addr), "i" (-EFAULT) \
282 : "cc")
283
284#ifndef __ARMEB__
285#define __get_user_asm_half(x,__gu_addr,err) \
286({ \
287 unsigned long __b1, __b2; \
288 __get_user_asm_byte(__b1, __gu_addr, err); \
289 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
290 (x) = __b1 | (__b2 << 8); \
291})
292#else
293#define __get_user_asm_half(x,__gu_addr,err) \
294({ \
295 unsigned long __b1, __b2; \
296 __get_user_asm_byte(__b1, __gu_addr, err); \
297 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
298 (x) = (__b1 << 8) | __b2; \
299})
300#endif
301
302#define __get_user_asm_word(x,addr,err) \
303 __asm__ __volatile__( \
304 "1: " TUSER(ldr) " %1,[%2],#0\n" \
305 "2:\n" \
306 " .pushsection .fixup,\"ax\"\n" \
307 " .align 2\n" \
308 "3: mov %0, %3\n" \
309 " mov %1, #0\n" \
310 " b 2b\n" \
311 " .popsection\n" \
312 " .pushsection __ex_table,\"a\"\n" \
313 " .align 3\n" \
314 " .long 1b, 3b\n" \
315 " .popsection" \
316 : "+r" (err), "=&r" (x) \
317 : "r" (addr), "i" (-EFAULT) \
318 : "cc")
319
320#define __put_user(x,ptr) \
321({ \
322 long __pu_err = 0; \
323 __put_user_err((x),(ptr),__pu_err); \
324 __pu_err; \
325})
326
327#define __put_user_error(x,ptr,err) \
328({ \
329 __put_user_err((x),(ptr),err); \
330 (void) 0; \
331})
332
333#define __put_user_err(x,ptr,err) \
334do { \
335 unsigned long __pu_addr = (unsigned long)(ptr); \
336 __typeof__(*(ptr)) __pu_val = (x); \
337 __chk_user_ptr(ptr); \
338 might_fault(); \
339 switch (sizeof(*(ptr))) { \
340 case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \
341 case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \
342 case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \
343 case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \
344 default: __put_user_bad(); \
345 } \
346} while (0)
347
348#define __put_user_asm_byte(x,__pu_addr,err) \
349 __asm__ __volatile__( \
350 "1: " TUSER(strb) " %1,[%2],#0\n" \
351 "2:\n" \
352 " .pushsection .fixup,\"ax\"\n" \
353 " .align 2\n" \
354 "3: mov %0, %3\n" \
355 " b 2b\n" \
356 " .popsection\n" \
357 " .pushsection __ex_table,\"a\"\n" \
358 " .align 3\n" \
359 " .long 1b, 3b\n" \
360 " .popsection" \
361 : "+r" (err) \
362 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
363 : "cc")
364
365#ifndef __ARMEB__
366#define __put_user_asm_half(x,__pu_addr,err) \
367({ \
368 unsigned long __temp = (unsigned long)(x); \
369 __put_user_asm_byte(__temp, __pu_addr, err); \
370 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
371})
372#else
373#define __put_user_asm_half(x,__pu_addr,err) \
374({ \
375 unsigned long __temp = (unsigned long)(x); \
376 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
377 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
378})
379#endif
380
381#define __put_user_asm_word(x,__pu_addr,err) \
382 __asm__ __volatile__( \
383 "1: " TUSER(str) " %1,[%2],#0\n" \
384 "2:\n" \
385 " .pushsection .fixup,\"ax\"\n" \
386 " .align 2\n" \
387 "3: mov %0, %3\n" \
388 " b 2b\n" \
389 " .popsection\n" \
390 " .pushsection __ex_table,\"a\"\n" \
391 " .align 3\n" \
392 " .long 1b, 3b\n" \
393 " .popsection" \
394 : "+r" (err) \
395 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
396 : "cc")
397
398#ifndef __ARMEB__
399#define __reg_oper0 "%R2"
400#define __reg_oper1 "%Q2"
401#else
402#define __reg_oper0 "%Q2"
403#define __reg_oper1 "%R2"
404#endif
405
406#define __put_user_asm_dword(x,__pu_addr,err) \
407 __asm__ __volatile__( \
408 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
409 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
410 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
411 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
412 "3:\n" \
413 " .pushsection .fixup,\"ax\"\n" \
414 " .align 2\n" \
415 "4: mov %0, %3\n" \
416 " b 3b\n" \
417 " .popsection\n" \
418 " .pushsection __ex_table,\"a\"\n" \
419 " .align 3\n" \
420 " .long 1b, 4b\n" \
421 " .long 2b, 4b\n" \
422 " .popsection" \
423 : "+r" (err), "+r" (__pu_addr) \
424 : "r" (x), "i" (-EFAULT) \
425 : "cc")
426
427
428#ifdef CONFIG_MMU
429extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
430extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
431extern unsigned long __must_check __copy_to_user_std(void __user *to, const void *from, unsigned long n);
432extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
433extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n);
434#else
435#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
436#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)
437#define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0)
438#endif
439
440static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
441{
442 if (access_ok(VERIFY_READ, from, n))
443 n = __copy_from_user(to, from, n);
444 else /* security hole - plug it */
445 memset(to, 0, n);
446 return n;
447}
448
449static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
450{
451 if (access_ok(VERIFY_WRITE, to, n))
452 n = __copy_to_user(to, from, n);
453 return n;
454}
455
456#define __copy_to_user_inatomic __copy_to_user
457#define __copy_from_user_inatomic __copy_from_user
458
459static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
460{
461 if (access_ok(VERIFY_WRITE, to, n))
462 n = __clear_user(to, n);
463 return n;
464}
465
466extern long strncpy_from_user(char *dest, const char __user *src, long count);
467
468extern __must_check long strlen_user(const char __user *str);
469extern __must_check long strnlen_user(const char __user *str, long n);
470
471#endif /* _ASMARM_UACCESS_H */
1/*
2 * arch/arm/include/asm/uaccess.h
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8#ifndef _ASMARM_UACCESS_H
9#define _ASMARM_UACCESS_H
10
11/*
12 * User space memory access functions
13 */
14#include <linux/string.h>
15#include <linux/thread_info.h>
16#include <asm/errno.h>
17#include <asm/memory.h>
18#include <asm/domain.h>
19#include <asm/unified.h>
20#include <asm/compiler.h>
21
22#define VERIFY_READ 0
23#define VERIFY_WRITE 1
24
25/*
26 * The exception table consists of pairs of addresses: the first is the
27 * address of an instruction that is allowed to fault, and the second is
28 * the address at which the program should continue. No registers are
29 * modified, so it is entirely up to the continuation code to figure out
30 * what to do.
31 *
32 * All the routines below use bits of fixup code that are out of line
33 * with the main instruction path. This means when everything is well,
34 * we don't even have to jump over them. Further, they do not intrude
35 * on our cache or tlb entries.
36 */
37
38struct exception_table_entry
39{
40 unsigned long insn, fixup;
41};
42
43extern int fixup_exception(struct pt_regs *regs);
44
45/*
46 * These two are intentionally not defined anywhere - if the kernel
47 * code generates any references to them, that's a bug.
48 */
49extern int __get_user_bad(void);
50extern int __put_user_bad(void);
51
52/*
53 * Note that this is actually 0x1,0000,0000
54 */
55#define KERNEL_DS 0x00000000
56#define get_ds() (KERNEL_DS)
57
58#ifdef CONFIG_MMU
59
60#define USER_DS TASK_SIZE
61#define get_fs() (current_thread_info()->addr_limit)
62
63static inline void set_fs(mm_segment_t fs)
64{
65 current_thread_info()->addr_limit = fs;
66 modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
67}
68
69#define segment_eq(a,b) ((a) == (b))
70
71#define __addr_ok(addr) ({ \
72 unsigned long flag; \
73 __asm__("cmp %2, %0; movlo %0, #0" \
74 : "=&r" (flag) \
75 : "0" (current_thread_info()->addr_limit), "r" (addr) \
76 : "cc"); \
77 (flag == 0); })
78
79/* We use 33-bit arithmetic here... */
80#define __range_ok(addr,size) ({ \
81 unsigned long flag, roksum; \
82 __chk_user_ptr(addr); \
83 __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
84 : "=&r" (flag), "=&r" (roksum) \
85 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
86 : "cc"); \
87 flag; })
88
89/*
90 * Single-value transfer routines. They automatically use the right
91 * size if we just have the right pointer type. Note that the functions
92 * which read from user space (*get_*) need to take care not to leak
93 * kernel data even if the calling code is buggy and fails to check
94 * the return value. This means zeroing out the destination variable
95 * or buffer on error. Normally this is done out of line by the
96 * fixup code, but there are a few places where it intrudes on the
97 * main code path. When we only write to user space, there is no
98 * problem.
99 */
100extern int __get_user_1(void *);
101extern int __get_user_2(void *);
102extern int __get_user_4(void *);
103
104#define __GUP_CLOBBER_1 "lr", "cc"
105#ifdef CONFIG_CPU_USE_DOMAINS
106#define __GUP_CLOBBER_2 "ip", "lr", "cc"
107#else
108#define __GUP_CLOBBER_2 "lr", "cc"
109#endif
110#define __GUP_CLOBBER_4 "lr", "cc"
111
112#define __get_user_x(__r2,__p,__e,__l,__s) \
113 __asm__ __volatile__ ( \
114 __asmeq("%0", "r0") __asmeq("%1", "r2") \
115 __asmeq("%3", "r1") \
116 "bl __get_user_" #__s \
117 : "=&r" (__e), "=r" (__r2) \
118 : "0" (__p), "r" (__l) \
119 : __GUP_CLOBBER_##__s)
120
121#define get_user(x,p) \
122 ({ \
123 unsigned long __limit = current_thread_info()->addr_limit - 1; \
124 register const typeof(*(p)) __user *__p asm("r0") = (p);\
125 register unsigned long __r2 asm("r2"); \
126 register unsigned long __l asm("r1") = __limit; \
127 register int __e asm("r0"); \
128 switch (sizeof(*(__p))) { \
129 case 1: \
130 __get_user_x(__r2, __p, __e, __l, 1); \
131 break; \
132 case 2: \
133 __get_user_x(__r2, __p, __e, __l, 2); \
134 break; \
135 case 4: \
136 __get_user_x(__r2, __p, __e, __l, 4); \
137 break; \
138 default: __e = __get_user_bad(); break; \
139 } \
140 x = (typeof(*(p))) __r2; \
141 __e; \
142 })
143
144extern int __put_user_1(void *, unsigned int);
145extern int __put_user_2(void *, unsigned int);
146extern int __put_user_4(void *, unsigned int);
147extern int __put_user_8(void *, unsigned long long);
148
149#define __put_user_x(__r2,__p,__e,__l,__s) \
150 __asm__ __volatile__ ( \
151 __asmeq("%0", "r0") __asmeq("%2", "r2") \
152 __asmeq("%3", "r1") \
153 "bl __put_user_" #__s \
154 : "=&r" (__e) \
155 : "0" (__p), "r" (__r2), "r" (__l) \
156 : "ip", "lr", "cc")
157
158#define put_user(x,p) \
159 ({ \
160 unsigned long __limit = current_thread_info()->addr_limit - 1; \
161 register const typeof(*(p)) __r2 asm("r2") = (x); \
162 register const typeof(*(p)) __user *__p asm("r0") = (p);\
163 register unsigned long __l asm("r1") = __limit; \
164 register int __e asm("r0"); \
165 switch (sizeof(*(__p))) { \
166 case 1: \
167 __put_user_x(__r2, __p, __e, __l, 1); \
168 break; \
169 case 2: \
170 __put_user_x(__r2, __p, __e, __l, 2); \
171 break; \
172 case 4: \
173 __put_user_x(__r2, __p, __e, __l, 4); \
174 break; \
175 case 8: \
176 __put_user_x(__r2, __p, __e, __l, 8); \
177 break; \
178 default: __e = __put_user_bad(); break; \
179 } \
180 __e; \
181 })
182
183#else /* CONFIG_MMU */
184
185/*
186 * uClinux has only one addr space, so has simplified address limits.
187 */
188#define USER_DS KERNEL_DS
189
190#define segment_eq(a,b) (1)
191#define __addr_ok(addr) (1)
192#define __range_ok(addr,size) (0)
193#define get_fs() (KERNEL_DS)
194
195static inline void set_fs(mm_segment_t fs)
196{
197}
198
199#define get_user(x,p) __get_user(x,p)
200#define put_user(x,p) __put_user(x,p)
201
202#endif /* CONFIG_MMU */
203
204#define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
205
206/*
207 * The "__xxx" versions of the user access functions do not verify the
208 * address space - it must have been done previously with a separate
209 * "access_ok()" call.
210 *
211 * The "xxx_error" versions set the third argument to EFAULT if an
212 * error occurs, and leave it unchanged on success. Note that these
213 * versions are void (ie, don't return a value as such).
214 */
215#define __get_user(x,ptr) \
216({ \
217 long __gu_err = 0; \
218 __get_user_err((x),(ptr),__gu_err); \
219 __gu_err; \
220})
221
222#define __get_user_error(x,ptr,err) \
223({ \
224 __get_user_err((x),(ptr),err); \
225 (void) 0; \
226})
227
228#define __get_user_err(x,ptr,err) \
229do { \
230 unsigned long __gu_addr = (unsigned long)(ptr); \
231 unsigned long __gu_val; \
232 __chk_user_ptr(ptr); \
233 switch (sizeof(*(ptr))) { \
234 case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \
235 case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \
236 case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \
237 default: (__gu_val) = __get_user_bad(); \
238 } \
239 (x) = (__typeof__(*(ptr)))__gu_val; \
240} while (0)
241
242#define __get_user_asm_byte(x,addr,err) \
243 __asm__ __volatile__( \
244 "1: " TUSER(ldrb) " %1,[%2],#0\n" \
245 "2:\n" \
246 " .pushsection .fixup,\"ax\"\n" \
247 " .align 2\n" \
248 "3: mov %0, %3\n" \
249 " mov %1, #0\n" \
250 " b 2b\n" \
251 " .popsection\n" \
252 " .pushsection __ex_table,\"a\"\n" \
253 " .align 3\n" \
254 " .long 1b, 3b\n" \
255 " .popsection" \
256 : "+r" (err), "=&r" (x) \
257 : "r" (addr), "i" (-EFAULT) \
258 : "cc")
259
260#ifndef __ARMEB__
261#define __get_user_asm_half(x,__gu_addr,err) \
262({ \
263 unsigned long __b1, __b2; \
264 __get_user_asm_byte(__b1, __gu_addr, err); \
265 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
266 (x) = __b1 | (__b2 << 8); \
267})
268#else
269#define __get_user_asm_half(x,__gu_addr,err) \
270({ \
271 unsigned long __b1, __b2; \
272 __get_user_asm_byte(__b1, __gu_addr, err); \
273 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
274 (x) = (__b1 << 8) | __b2; \
275})
276#endif
277
278#define __get_user_asm_word(x,addr,err) \
279 __asm__ __volatile__( \
280 "1: " TUSER(ldr) " %1,[%2],#0\n" \
281 "2:\n" \
282 " .pushsection .fixup,\"ax\"\n" \
283 " .align 2\n" \
284 "3: mov %0, %3\n" \
285 " mov %1, #0\n" \
286 " b 2b\n" \
287 " .popsection\n" \
288 " .pushsection __ex_table,\"a\"\n" \
289 " .align 3\n" \
290 " .long 1b, 3b\n" \
291 " .popsection" \
292 : "+r" (err), "=&r" (x) \
293 : "r" (addr), "i" (-EFAULT) \
294 : "cc")
295
296#define __put_user(x,ptr) \
297({ \
298 long __pu_err = 0; \
299 __put_user_err((x),(ptr),__pu_err); \
300 __pu_err; \
301})
302
303#define __put_user_error(x,ptr,err) \
304({ \
305 __put_user_err((x),(ptr),err); \
306 (void) 0; \
307})
308
309#define __put_user_err(x,ptr,err) \
310do { \
311 unsigned long __pu_addr = (unsigned long)(ptr); \
312 __typeof__(*(ptr)) __pu_val = (x); \
313 __chk_user_ptr(ptr); \
314 switch (sizeof(*(ptr))) { \
315 case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \
316 case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \
317 case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \
318 case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \
319 default: __put_user_bad(); \
320 } \
321} while (0)
322
323#define __put_user_asm_byte(x,__pu_addr,err) \
324 __asm__ __volatile__( \
325 "1: " TUSER(strb) " %1,[%2],#0\n" \
326 "2:\n" \
327 " .pushsection .fixup,\"ax\"\n" \
328 " .align 2\n" \
329 "3: mov %0, %3\n" \
330 " b 2b\n" \
331 " .popsection\n" \
332 " .pushsection __ex_table,\"a\"\n" \
333 " .align 3\n" \
334 " .long 1b, 3b\n" \
335 " .popsection" \
336 : "+r" (err) \
337 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
338 : "cc")
339
340#ifndef __ARMEB__
341#define __put_user_asm_half(x,__pu_addr,err) \
342({ \
343 unsigned long __temp = (unsigned long)(x); \
344 __put_user_asm_byte(__temp, __pu_addr, err); \
345 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
346})
347#else
348#define __put_user_asm_half(x,__pu_addr,err) \
349({ \
350 unsigned long __temp = (unsigned long)(x); \
351 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
352 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
353})
354#endif
355
356#define __put_user_asm_word(x,__pu_addr,err) \
357 __asm__ __volatile__( \
358 "1: " TUSER(str) " %1,[%2],#0\n" \
359 "2:\n" \
360 " .pushsection .fixup,\"ax\"\n" \
361 " .align 2\n" \
362 "3: mov %0, %3\n" \
363 " b 2b\n" \
364 " .popsection\n" \
365 " .pushsection __ex_table,\"a\"\n" \
366 " .align 3\n" \
367 " .long 1b, 3b\n" \
368 " .popsection" \
369 : "+r" (err) \
370 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
371 : "cc")
372
373#ifndef __ARMEB__
374#define __reg_oper0 "%R2"
375#define __reg_oper1 "%Q2"
376#else
377#define __reg_oper0 "%Q2"
378#define __reg_oper1 "%R2"
379#endif
380
381#define __put_user_asm_dword(x,__pu_addr,err) \
382 __asm__ __volatile__( \
383 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
384 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
385 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
386 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
387 "3:\n" \
388 " .pushsection .fixup,\"ax\"\n" \
389 " .align 2\n" \
390 "4: mov %0, %3\n" \
391 " b 3b\n" \
392 " .popsection\n" \
393 " .pushsection __ex_table,\"a\"\n" \
394 " .align 3\n" \
395 " .long 1b, 4b\n" \
396 " .long 2b, 4b\n" \
397 " .popsection" \
398 : "+r" (err), "+r" (__pu_addr) \
399 : "r" (x), "i" (-EFAULT) \
400 : "cc")
401
402
403#ifdef CONFIG_MMU
404extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
405extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
406extern unsigned long __must_check __copy_to_user_std(void __user *to, const void *from, unsigned long n);
407extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
408extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n);
409#else
410#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
411#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)
412#define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0)
413#endif
414
415extern unsigned long __must_check __strncpy_from_user(char *to, const char __user *from, unsigned long count);
416extern unsigned long __must_check __strnlen_user(const char __user *s, long n);
417
418static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
419{
420 if (access_ok(VERIFY_READ, from, n))
421 n = __copy_from_user(to, from, n);
422 else /* security hole - plug it */
423 memset(to, 0, n);
424 return n;
425}
426
427static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
428{
429 if (access_ok(VERIFY_WRITE, to, n))
430 n = __copy_to_user(to, from, n);
431 return n;
432}
433
434#define __copy_to_user_inatomic __copy_to_user
435#define __copy_from_user_inatomic __copy_from_user
436
437static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
438{
439 if (access_ok(VERIFY_WRITE, to, n))
440 n = __clear_user(to, n);
441 return n;
442}
443
444static inline long __must_check strncpy_from_user(char *dst, const char __user *src, long count)
445{
446 long res = -EFAULT;
447 if (access_ok(VERIFY_READ, src, 1))
448 res = __strncpy_from_user(dst, src, count);
449 return res;
450}
451
452#define strlen_user(s) strnlen_user(s, ~0UL >> 1)
453
454static inline long __must_check strnlen_user(const char __user *s, long n)
455{
456 unsigned long res = 0;
457
458 if (__addr_ok(s))
459 res = __strnlen_user(s, n);
460
461 return res;
462}
463
464#endif /* _ASMARM_UACCESS_H */