1 /* $Id: uaccess.h,v 1.10 2000/03/24 13:53:45 gniibe Exp $
3 * User space memory access functions
5 * Copyright (C) 1999 Niibe Yutaka
8 * MIPS implementation version 1.15 by
9 * Copyright (C) 1996, 1997, 1998 by Ralf Baechle
12 #ifndef __ASM_SH_UACCESS_H
13 #define __ASM_SH_UACCESS_H
15 #include <linux/errno.h>
16 #include <linux/sched.h>
19 #define VERIFY_WRITE 1
22 * The fs value determines whether argument validity checking should be
23 * performed or not. If get_fs() == USER_DS, checking is performed, with
24 * get_fs() == KERNEL_DS, checking is bypassed.
26 * For historical reasons (Data Segment Register?), these macros are misnamed.
29 #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
31 #define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF)
32 #define USER_DS MAKE_MM_SEG(0x80000000)
34 #define get_ds() (KERNEL_DS)
35 #define get_fs() (current->addr_limit)
36 #define set_fs(x) (current->addr_limit=(x))
38 #define segment_eq(a,b) ((a).seg == (b).seg)
40 #define __addr_ok(addr) ((unsigned long)(addr) < (current->addr_limit.seg))
43 * Uhhuh, this needs 33-bit arithmetic. We have a carry..
45 * sum := addr + size; carry? --> flag = true;
46 * if (sum >= addr_limit) flag = true;
48 #define __range_ok(addr,size) ({ \
49 unsigned long flag,sum; \
50 __asm__("clrt; addc %3, %1; movt %0; cmp/hi %4, %1; rotcl %0" \
51 :"=&r" (flag), "=r" (sum) \
52 :"1" (addr), "r" ((int)(size)), "r" (current->addr_limit.seg)); \
55 #define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
56 #define __access_ok(addr,size) (__range_ok(addr,size) == 0)
58 extern inline int verify_area(int type
, const void * addr
, unsigned long size
)
60 return access_ok(type
,addr
,size
) ? 0 : -EFAULT
;
64 * Uh, these should become the main single-value transfer routines ...
65 * They automatically use the right size if we just have the right
68 * As MIPS uses the same address space for kernel and user data, we
69 * can just do these as direct assignments.
72 * (a) re-use the arguments for side effects (sizeof is ok)
73 * (b) require any knowledge of processes at this stage
75 #define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr)))
76 #define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))
79 * The "__xxx" versions do not do address space checking, useful when
80 * doing multiple accesses to the same area (the user has to do the
81 * checks by hand with "access_ok()")
83 #define __put_user(x,ptr) __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
84 #define __get_user(x,ptr) __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
87 * The "xxx_ret" versions return constant specified in third argument, if
88 * something bad happens. These macros can be optimized for the
89 * case of just returning from the function xxx_ret is used.
92 #define put_user_ret(x,ptr,ret) ({ \
93 if (put_user(x,ptr)) return ret; })
95 #define get_user_ret(x,ptr,ret) ({ \
96 if (get_user(x,ptr)) return ret; })
98 #define __put_user_ret(x,ptr,ret) ({ \
99 if (__put_user(x,ptr)) return ret; })
101 #define __get_user_ret(x,ptr,ret) ({ \
102 if (__get_user(x,ptr)) return ret; })
104 struct __large_struct
{ unsigned long buf
[100]; };
105 #define __m(x) (*(struct __large_struct *)(x))
107 #define __get_user_nocheck(x,ptr,size) ({ \
109 __typeof(*(ptr)) __gu_val; \
111 __asm__("":"=r" (__gu_val)); \
112 __gu_addr = (long) (ptr); \
113 __asm__("":"=r" (__gu_err)); \
115 case 1: __get_user_asm("b"); break; \
116 case 2: __get_user_asm("w"); break; \
117 case 4: __get_user_asm("l"); break; \
118 default: __get_user_unknown(); break; \
119 } x = (__typeof__(*(ptr))) __gu_val; __gu_err; })
121 #define __get_user_check(x,ptr,size) ({ \
123 __typeof__(*(ptr)) __gu_val; \
125 __asm__("":"=r" (__gu_val)); \
126 __gu_addr = (long) (ptr); \
127 __asm__("":"=r" (__gu_err)); \
128 if (__access_ok(__gu_addr,size)) { \
130 case 1: __get_user_asm("b"); break; \
131 case 2: __get_user_asm("w"); break; \
132 case 4: __get_user_asm("l"); break; \
133 default: __get_user_unknown(); break; \
134 } } x = (__typeof__(*(ptr))) __gu_val; __gu_err; })
136 #define __get_user_asm(insn) \
138 __asm__ __volatile__( \
140 "mov." insn " %2, %1\n\t" \
143 ".section .fixup,\"ax\"\n" \
151 ".section __ex_table,\"a\"\n\t" \
154 :"=&r" (__gu_err), "=&r" (__gu_val) \
155 :"m" (__m(__gu_addr)), "i" (-EFAULT)); })
157 extern void __get_user_unknown(void);
159 #define __put_user_nocheck(x,ptr,size) ({ \
161 __typeof__(*(ptr)) __pu_val; \
164 __pu_addr = (long) (ptr); \
165 __asm__("":"=r" (__pu_err)); \
167 case 1: __put_user_asm("b"); break; \
168 case 2: __put_user_asm("w"); break; \
169 case 4: __put_user_asm("l"); break; \
170 default: __put_user_unknown(); break; \
173 #define __put_user_check(x,ptr,size) ({ \
175 __typeof__(*(ptr)) __pu_val; \
178 __pu_addr = (long) (ptr); \
179 __asm__("":"=r" (__pu_err)); \
180 if (__access_ok(__pu_addr,size)) { \
182 case 1: __put_user_asm("b"); break; \
183 case 2: __put_user_asm("w"); break; \
184 case 4: __put_user_asm("l"); break; \
185 default: __put_user_unknown(); break; \
188 #define __put_user_asm(insn) \
190 __asm__ __volatile__( \
192 "mov." insn " %1, %2\n\t" \
195 ".section .fixup,\"ax\"\n" \
203 ".section __ex_table,\"a\"\n\t" \
207 :"r" (__pu_val), "m" (__m(__pu_addr)), "i" (-EFAULT)); })
209 extern void __put_user_unknown(void);
211 /* Generic arbitrary sized copy. */
212 /* Return the number of bytes NOT copied */
213 /* XXX: should be such that: 4byte and the rest. */
214 extern __inline__ __kernel_size_t
215 __copy_user(void *__to
, const void *__from
, __kernel_size_t __n
)
217 unsigned long __dummy
, _f
, _t
;
221 __asm__
__volatile__(
230 ".section .fixup,\"ax\"\n"
238 ".section __ex_table,\"a\"\n"
243 : "=r" (res
), "=&z" (__dummy
), "=r" (_f
), "=r" (_t
)
244 : "2" (__from
), "3" (__to
), "0" (res
)
250 #define copy_to_user(to,from,n) ({ \
251 void *__copy_to = (void *) (to); \
252 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
253 __kernel_size_t __copy_res; \
254 if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \
255 __copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \
256 } else __copy_res = __copy_size; \
259 #define copy_to_user_ret(to,from,n,retval) ({ \
260 if (copy_to_user(to,from,n)) \
264 #define __copy_to_user(to,from,n) \
265 __copy_user((void *)(to), \
268 #define __copy_to_user_ret(to,from,n,retval) ({ \
269 if (__copy_to_user(to,from,n)) \
273 #define copy_from_user(to,from,n) ({ \
274 void *__copy_to = (void *) (to); \
275 void *__copy_from = (void *) (from); \
276 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
277 __kernel_size_t __copy_res; \
278 if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \
279 __copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \
280 } else __copy_res = __copy_size; \
283 #define copy_from_user_ret(to,from,n,retval) ({ \
284 if (copy_from_user(to,from,n)) \
288 #define __copy_from_user(to,from,n) \
289 __copy_user((void *)(to), \
292 #define __copy_from_user_ret(to,from,n,retval) ({ \
293 if (__copy_from_user(to,from,n)) \
297 /* XXX: Not sure it works well..
298 should be such that: 4byte clear and the rest. */
299 extern __inline__ __kernel_size_t
300 __clear_user(void *addr
, __kernel_size_t size
)
304 __asm__
__volatile__(
312 ".section .fixup,\"ax\"\n"
320 ".section __ex_table,\"a\"\n"
324 : "=r" (size
), "=r" (__a
)
325 : "0" (size
), "1" (addr
), "r" (0));
330 #define clear_user(addr,n) ({ \
331 void * __cl_addr = (addr); \
332 unsigned long __cl_size = (n); \
333 if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
334 __cl_size = __clear_user(__cl_addr, __cl_size); \
337 extern __inline__
int
338 __strncpy_from_user(unsigned long __dest
, unsigned long __src
, int __count
)
341 unsigned long __dummy
, _d
, _s
;
343 __asm__
__volatile__(
356 ".section .fixup,\"ax\"\n"
364 ".section __ex_table,\"a\"\n"
368 : "=r" (res
), "=&z" (__dummy
), "=r" (_s
), "=r" (_d
)
369 : "0" (__count
), "2" (__src
), "3" (__dest
), "r" (__count
),
376 #define strncpy_from_user(dest,src,count) ({ \
377 unsigned long __sfu_src = (unsigned long) (src); \
378 int __sfu_count = (int) (count); \
379 long __sfu_res = -EFAULT; \
380 if(__access_ok(__sfu_src, __sfu_count)) { \
381 __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
384 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
387 * Return the size of a string (including the ending 0!)
389 extern __inline__
long __strnlen_user(const char *__s
, long __n
)
392 unsigned long __dummy
;
394 __asm__
__volatile__(
399 "mov.b @(%0,%3), %1\n\t"
404 ".section .fixup,\"ax\"\n"
412 ".section __ex_table,\"a\"\n"
416 : "=z" (res
), "=&r" (__dummy
)
417 : "0" (0), "r" (__s
), "r" (__n
), "i" (-EFAULT
));
421 extern __inline__
long strnlen_user(const char *s
, long n
)
426 return __strnlen_user(s
, n
);
429 struct exception_table_entry
431 unsigned long insn
, fixup
;
434 /* Returns 0 if exception not found and fixup.unit otherwise. */
435 extern unsigned long search_exception_table(unsigned long addr
);
437 /* Returns the new pc */
438 #define fixup_exception(map_reg, fixup_unit, pc) \
443 #endif /* __ASM_SH_UACCESS_H */