include/asm-sh/uaccess_64.h

   1 #ifndef __ASM_SH_UACCESS_64_H
   2 #define __ASM_SH_UACCESS_64_H
   3
   4 /*
   5  * include/asm-sh/uaccess_64.h
   6  *
   7  * Copyright (C) 2000, 2001  Paolo Alberelli
   8  * Copyright (C) 2003, 2004  Paul Mundt
   9  *
  10  * User space memory access functions
  11  *
  12  * Copyright (C) 1999  Niibe Yutaka
  13  *
  14  *  Based on:
  15  *     MIPS implementation version 1.15 by
  16  *              Copyright (C) 1996, 1997, 1998 by Ralf Baechle
  17  *     and i386 version.
  18  *
  19  * This file is subject to the terms and conditions of the GNU General Public
  20  * License.  See the file "COPYING" in the main directory of this archive
  21  * for more details.
  22  */
  23 #include <linux/errno.h>
  24 #include <linux/sched.h>
  25
  26 #define VERIFY_READ    0
  27 #define VERIFY_WRITE   1
  28
  29 /*
  30  * The fs value determines whether argument validity checking should be
  31  * performed or not.  If get_fs() == USER_DS, checking is performed, with
  32  * get_fs() == KERNEL_DS, checking is bypassed.
  33  *
  34  * For historical reasons (Data Segment Register?), these macros are misnamed.
  35  */
  36
  37 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
  38
  39 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
  40 #define USER_DS         MAKE_MM_SEG(0x80000000)
  41
  42 #define get_ds()        (KERNEL_DS)
  43 #define get_fs()        (current_thread_info()->addr_limit)
  44 #define set_fs(x)       (current_thread_info()->addr_limit=(x))
  45
  46 #define segment_eq(a,b) ((a).seg == (b).seg)
  47
  48 #define __addr_ok(addr) ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
  49
  50 /*
  51  * Uhhuh, this needs 33-bit arithmetic. We have a carry..
  52  *
  53  * sum := addr + size;  carry? --> flag = true;
  54  * if (sum >= addr_limit) flag = true;
  55  */
  56 #define __range_ok(addr,size) (((unsigned long) (addr) + (size) < (current_thread_info()->addr_limit.seg)) ? 0 : 1)
  57
  58 #define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
  59 #define __access_ok(addr,size) (__range_ok(addr,size) == 0)
  60
  61 /*
  62  * Uh, these should become the main single-value transfer routines ...
  63  * They automatically use the right size if we just have the right
  64  * pointer type ...
  65  *
  66  * As MIPS uses the same address space for kernel and user data, we
  67  * can just do these as direct assignments.
  68  *
  69  * Careful to not
  70  * (a) re-use the arguments for side effects (sizeof is ok)
  71  * (b) require any knowledge of processes at this stage
  72  */
  73 #define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr)))
  74 #define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))
  75
  76 /*
  77  * The "__xxx" versions do not do address space checking, useful when
  78  * doing multiple accesses to the same area (the user has to do the
  79  * checks by hand with "access_ok()")
  80  */
  81 #define __put_user(x,ptr) __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
  82 #define __get_user(x,ptr) __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
  83
  84 /*
  85  * The "xxx_ret" versions return constant specified in third argument, if
  86  * something bad happens. These macros can be optimized for the
  87  * case of just returning from the function xxx_ret is used.
  88  */
  89
  90 #define put_user_ret(x,ptr,ret) ({ \
  91 if (put_user(x,ptr)) return ret; })
  92
  93 #define get_user_ret(x,ptr,ret) ({ \
  94 if (get_user(x,ptr)) return ret; })
  95
  96 #define __put_user_ret(x,ptr,ret) ({ \
  97 if (__put_user(x,ptr)) return ret; })
  98
  99 #define __get_user_ret(x,ptr,ret) ({ \
 100 if (__get_user(x,ptr)) return ret; })
 101
 102 struct __large_struct { unsigned long buf[100]; };
 103 #define __m(x) (*(struct __large_struct *)(x))
 104
 105 #define __get_user_size(x,ptr,size,retval)                      \
 106 do {                                                            \
 107         retval = 0;                                             \
 108         switch (size) {                                         \
 109         case 1:                                                 \
 110                 retval = __get_user_asm_b(x, ptr);              \
 111                 break;                                          \
 112         case 2:                                                 \
 113                 retval = __get_user_asm_w(x, ptr);              \
 114                 break;                                          \
 115         case 4:                                                 \
 116                 retval = __get_user_asm_l(x, ptr);              \
 117                 break;                                          \
 118         case 8:                                                 \
 119                 retval = __get_user_asm_q(x, ptr);              \
 120                 break;                                          \
 121         default:                                                \
 122                 __get_user_unknown();                           \
 123                 break;                                          \
 124         }                                                       \
 125 } while (0)
 126
 127 #define __get_user_nocheck(x,ptr,size)                          \
 128 ({                                                              \
 129         long __gu_err, __gu_val;                                \
 130         __get_user_size((void *)&__gu_val, (long)(ptr),         \
 131                         (size), __gu_err);                      \
 132         (x) = (__typeof__(*(ptr)))__gu_val;                     \
 133         __gu_err;                                               \
 134 })
 135
 136 #define __get_user_check(x,ptr,size)                            \
 137 ({                                                              \
 138         long __gu_addr = (long)(ptr);                           \
 139         long __gu_err = -EFAULT, __gu_val;                      \
 140         if (__access_ok(__gu_addr, (size)))                     \
 141                 __get_user_size((void *)&__gu_val, __gu_addr,   \
 142                                 (size), __gu_err);              \
 143         (x) = (__typeof__(*(ptr))) __gu_val;                    \
 144         __gu_err;                                               \
 145 })
 146
 147 extern long __get_user_asm_b(void *, long);
 148 extern long __get_user_asm_w(void *, long);
 149 extern long __get_user_asm_l(void *, long);
 150 extern long __get_user_asm_q(void *, long);
 151 extern void __get_user_unknown(void);
 152
 153 #define __put_user_size(x,ptr,size,retval)                      \
 154 do {                                                            \
 155         retval = 0;                                             \
 156         switch (size) {                                         \
 157         case 1:                                                 \
 158                 retval = __put_user_asm_b(x, ptr);              \
 159                 break;                                          \
 160         case 2:                                                 \
 161                 retval = __put_user_asm_w(x, ptr);              \
 162                 break;                                          \
 163         case 4:                                                 \
 164                 retval = __put_user_asm_l(x, ptr);              \
 165                 break;                                          \
 166         case 8:                                                 \
 167                 retval = __put_user_asm_q(x, ptr);              \
 168                 break;                                          \
 169         default:                                                \
 170                 __put_user_unknown();                           \
 171         }                                                       \
 172 } while (0)
 173
 174 #define __put_user_nocheck(x,ptr,size)                          \
 175 ({                                                              \
 176         long __pu_err;                                          \
 177         __typeof__(*(ptr)) __pu_val = (x);                      \
 178         __put_user_size((void *)&__pu_val, (long)(ptr), (size), __pu_err); \
 179         __pu_err;                                               \
 180 })
 181
 182 #define __put_user_check(x,ptr,size)                            \
 183 ({                                                              \
 184         long __pu_err = -EFAULT;                                \
 185         long __pu_addr = (long)(ptr);                           \
 186         __typeof__(*(ptr)) __pu_val = (x);                      \
 187                                                                 \
 188         if (__access_ok(__pu_addr, (size)))                     \
 189                 __put_user_size((void *)&__pu_val, __pu_addr, (size), __pu_err);\
 190         __pu_err;                                               \
 191 })
 192
 193 extern long __put_user_asm_b(void *, long);
 194 extern long __put_user_asm_w(void *, long);
 195 extern long __put_user_asm_l(void *, long);
 196 extern long __put_user_asm_q(void *, long);
 197 extern void __put_user_unknown(void);
 198
 199 \f
 200 /* Generic arbitrary sized copy.  */
 201 /* Return the number of bytes NOT copied */
 202 /* XXX: should be such that: 4byte and the rest. */
 203 extern __kernel_size_t __copy_user(void *__to, const void *__from, __kernel_size_t __n);
 204
 205 #define copy_to_user_ret(to,from,n,retval) ({ \
 206 if (copy_to_user(to,from,n)) \
 207         return retval; \
 208 })
 209
 210 #define __copy_to_user(to,from,n)               \
 211         __copy_user((void *)(to),               \
 212                     (void *)(from), n)
 213
 214 #define __copy_to_user_ret(to,from,n,retval) ({ \
 215 if (__copy_to_user(to,from,n)) \
 216         return retval; \
 217 })
 218
 219 #define copy_from_user_ret(to,from,n,retval) ({ \
 220 if (copy_from_user(to,from,n)) \
 221         return retval; \
 222 })
 223
 224 #define __copy_from_user(to,from,n)             \
 225         __copy_user((void *)(to),               \
 226                     (void *)(from), n)
 227
 228 #define __copy_from_user_ret(to,from,n,retval) ({ \
 229 if (__copy_from_user(to,from,n)) \
 230         return retval; \
 231 })
 232
 233 #define __copy_to_user_inatomic __copy_to_user
 234 #define __copy_from_user_inatomic __copy_from_user
 235
 236 /* XXX: Not sure it works well..
 237    should be such that: 4byte clear and the rest. */
 238 extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
 239
 240 #define clear_user(addr,n) ({ \
 241 void * __cl_addr = (addr); \
 242 unsigned long __cl_size = (n); \
 243 if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
 244 __cl_size = __clear_user(__cl_addr, __cl_size); \
 245 __cl_size; })
 246
 247 extern int __strncpy_from_user(unsigned long __dest, unsigned long __src, int __count);
 248
 249 #define strncpy_from_user(dest,src,count) ({ \
 250 unsigned long __sfu_src = (unsigned long) (src); \
 251 int __sfu_count = (int) (count); \
 252 long __sfu_res = -EFAULT; \
 253 if(__access_ok(__sfu_src, __sfu_count)) { \
 254 __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
 255 } __sfu_res; })
 256
 257 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
 258
 259 /*
 260  * Return the size of a string (including the ending 0!)
 261  */
 262 extern long __strnlen_user(const char *__s, long __n);
 263
 264 static inline long strnlen_user(const char *s, long n)
 265 {
 266         if (!__addr_ok(s))
 267                 return 0;
 268         else
 269                 return __strnlen_user(s, n);
 270 }
 271
 272 struct exception_table_entry
 273 {
 274         unsigned long insn, fixup;
 275 };
 276
 277 #define ARCH_HAS_SEARCH_EXTABLE
 278
 279 /* Returns 0 if exception not found and fixup.unit otherwise.  */
 280 extern unsigned long search_exception_table(unsigned long addr);
 281 extern const struct exception_table_entry *search_exception_tables (unsigned long addr);
 282
 283 #endif /* __ASM_SH_UACCESS_64_H */