include/asm-sh64/uaccess.h

   1 #ifndef __ASM_SH64_UACCESS_H
   2 #define __ASM_SH64_UACCESS_H
   3
   4 /*
   5  * This file is subject to the terms and conditions of the GNU General Public
   6  * License.  See the file "COPYING" in the main directory of this archive
   7  * for more details.
   8  *
   9  * include/asm-sh64/uaccess.h
  10  *
  11  * Copyright (C) 2000, 2001  Paolo Alberelli
  12  * Copyright (C) 2003, 2004  Paul Mundt
  13  *
  14  * User space memory access functions
  15  *
  16  * Copyright (C) 1999  Niibe Yutaka
  17  *
  18  *  Based on:
  19  *     MIPS implementation version 1.15 by
  20  *              Copyright (C) 1996, 1997, 1998 by Ralf Baechle
  21  *     and i386 version.
  22  *
  23  */
  24
  25 #include <linux/errno.h>
  26 #include <linux/sched.h>
  27
  28 #define VERIFY_READ    0
  29 #define VERIFY_WRITE   1
  30
  31 /*
  32  * The fs value determines whether argument validity checking should be
  33  * performed or not.  If get_fs() == USER_DS, checking is performed, with
  34  * get_fs() == KERNEL_DS, checking is bypassed.
  35  *
  36  * For historical reasons (Data Segment Register?), these macros are misnamed.
  37  */
  38
  39 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
  40
  41 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
  42 #define USER_DS         MAKE_MM_SEG(0x80000000)
  43
  44 #define get_ds()        (KERNEL_DS)
  45 #define get_fs()        (current_thread_info()->addr_limit)
  46 #define set_fs(x)       (current_thread_info()->addr_limit=(x))
  47
  48 #define segment_eq(a,b) ((a).seg == (b).seg)
  49
  50 #define __addr_ok(addr) ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
  51
  52 /*
  53  * Uhhuh, this needs 33-bit arithmetic. We have a carry..
  54  *
  55  * sum := addr + size;  carry? --> flag = true;
  56  * if (sum >= addr_limit) flag = true;
  57  */
  58 #define __range_ok(addr,size) (((unsigned long) (addr) + (size) < (current_thread_info()->addr_limit.seg)) ? 0 : 1)
  59
  60 #define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
  61 #define __access_ok(addr,size) (__range_ok(addr,size) == 0)
  62
  63 extern inline int verify_area(int type, const void __user * addr, unsigned long size)
  64 {
  65         return access_ok(type,addr,size) ? 0 : -EFAULT;
  66 }
  67
  68 /*
  69  * Uh, these should become the main single-value transfer routines ...
  70  * They automatically use the right size if we just have the right
  71  * pointer type ...
  72  *
  73  * As MIPS uses the same address space for kernel and user data, we
  74  * can just do these as direct assignments.
  75  *
  76  * Careful to not
  77  * (a) re-use the arguments for side effects (sizeof is ok)
  78  * (b) require any knowledge of processes at this stage
  79  */
  80 #define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr)))
  81 #define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))
  82
  83 /*
  84  * The "__xxx" versions do not do address space checking, useful when
  85  * doing multiple accesses to the same area (the user has to do the
  86  * checks by hand with "access_ok()")
  87  */
  88 #define __put_user(x,ptr) __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
  89 #define __get_user(x,ptr) __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
  90
  91 /*
  92  * The "xxx_ret" versions return constant specified in third argument, if
  93  * something bad happens. These macros can be optimized for the
  94  * case of just returning from the function xxx_ret is used.
  95  */
  96
  97 #define put_user_ret(x,ptr,ret) ({ \
  98 if (put_user(x,ptr)) return ret; })
  99
 100 #define get_user_ret(x,ptr,ret) ({ \
 101 if (get_user(x,ptr)) return ret; })
 102
 103 #define __put_user_ret(x,ptr,ret) ({ \
 104 if (__put_user(x,ptr)) return ret; })
 105
 106 #define __get_user_ret(x,ptr,ret) ({ \
 107 if (__get_user(x,ptr)) return ret; })
 108
 109 struct __large_struct { unsigned long buf[100]; };
 110 #define __m(x) (*(struct __large_struct *)(x))
 111
 112 #define __get_user_size(x,ptr,size,retval)                      \
 113 do {                                                            \
 114         retval = 0;                                             \
 115         switch (size) {                                         \
 116         case 1:                                                 \
 117                 retval = __get_user_asm_b(x, ptr);              \
 118                 break;                                          \
 119         case 2:                                                 \
 120                 retval = __get_user_asm_w(x, ptr);              \
 121                 break;                                          \
 122         case 4:                                                 \
 123                 retval = __get_user_asm_l(x, ptr);              \
 124                 break;                                          \
 125         case 8:                                                 \
 126                 retval = __get_user_asm_q(x, ptr);              \
 127                 break;                                          \
 128         default:                                                \
 129                 __get_user_unknown();                           \
 130                 break;                                          \
 131         }                                                       \
 132 } while (0)
 133
 134 #define __get_user_nocheck(x,ptr,size)                          \
 135 ({                                                              \
 136         long __gu_addr = (long)(ptr);                           \
 137         long __gu_err;                                          \
 138         __typeof(*(ptr)) __gu_val;                              \
 139         __asm__ ("":"=r" (__gu_val));                           \
 140         __asm__ ("":"=r" (__gu_err));                           \
 141         __get_user_size((void *)&__gu_val, __gu_addr, (size), __gu_err); \
 142         (x) = (__typeof__(*(ptr))) __gu_val;                    \
 143         __gu_err;                                               \
 144 })
 145
 146 #define __get_user_check(x,ptr,size)                            \
 147 ({                                                              \
 148         long __gu_addr = (long)(ptr);                           \
 149         long __gu_err = -EFAULT;                                \
 150         __typeof(*(ptr)) __gu_val;                              \
 151         __asm__ ("":"=r" (__gu_val));                           \
 152         __asm__ ("":"=r" (__gu_err));                           \
 153         if (__access_ok(__gu_addr, (size)))                     \
 154                 __get_user_size((void *)&__gu_val, __gu_addr, (size), __gu_err); \
 155         (x) = (__typeof__(*(ptr))) __gu_val;                    \
 156         __gu_err;                                               \
 157 })
 158
 159 extern long __get_user_asm_b(void *, long);
 160 extern long __get_user_asm_w(void *, long);
 161 extern long __get_user_asm_l(void *, long);
 162 extern long __get_user_asm_q(void *, long);
 163 extern void __get_user_unknown(void);
 164
 165 #define __put_user_size(x,ptr,size,retval)                      \
 166 do {                                                            \
 167         retval = 0;                                             \
 168         switch (size) {                                         \
 169         case 1:                                                 \
 170                 retval = __put_user_asm_b(x, ptr);              \
 171                 break;                                          \
 172         case 2:                                                 \
 173                 retval = __put_user_asm_w(x, ptr);              \
 174                 break;                                          \
 175         case 4:                                                 \
 176                 retval = __put_user_asm_l(x, ptr);              \
 177                 break;                                          \
 178         case 8:                                                 \
 179                 retval = __put_user_asm_q(x, ptr);              \
 180                 break;                                          \
 181         default:                                                \
 182                 __put_user_unknown();                           \
 183         }                                                       \
 184 } while (0)
 185
 186 #define __put_user_nocheck(x,ptr,size)                          \
 187 ({                                                              \
 188         long __pu_err;                                          \
 189         __typeof__(*(ptr)) __pu_val = (x);                      \
 190         __put_user_size((void *)&__pu_val, (long)(ptr), (size), __pu_err); \
 191         __pu_err;                                               \
 192 })
 193
 194 #define __put_user_check(x,ptr,size)                            \
 195 ({                                                              \
 196         long __pu_err = -EFAULT;                                \
 197         long __pu_addr = (long)(ptr);                           \
 198         __typeof__(*(ptr)) __pu_val = (x);                      \
 199                                                                 \
 200         if (__access_ok(__pu_addr, (size)))                     \
 201                 __put_user_size((void *)&__pu_val, __pu_addr, (size), __pu_err);\
 202         __pu_err;                                               \
 203 })
 204
 205 extern long __put_user_asm_b(void *, long);
 206 extern long __put_user_asm_w(void *, long);
 207 extern long __put_user_asm_l(void *, long);
 208 extern long __put_user_asm_q(void *, long);
 209 extern void __put_user_unknown(void);
 210
 211 \f
 212 /* Generic arbitrary sized copy.  */
 213 /* Return the number of bytes NOT copied */
 214 /* XXX: should be such that: 4byte and the rest. */
 215 extern __kernel_size_t __copy_user(void *__to, const void *__from, __kernel_size_t __n);
 216
 217 #define copy_to_user(to,from,n) ({ \
 218 void *__copy_to = (void *) (to); \
 219 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
 220 __kernel_size_t __copy_res; \
 221 if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \
 222 __copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \
 223 } else __copy_res = __copy_size; \
 224 __copy_res; })
 225
 226 #define copy_to_user_ret(to,from,n,retval) ({ \
 227 if (copy_to_user(to,from,n)) \
 228         return retval; \
 229 })
 230
 231 #define __copy_to_user(to,from,n)               \
 232         __copy_user((void *)(to),               \
 233                     (void *)(from), n)
 234
 235 #define __copy_to_user_ret(to,from,n,retval) ({ \
 236 if (__copy_to_user(to,from,n)) \
 237         return retval; \
 238 })
 239
 240 #define copy_from_user(to,from,n) ({ \
 241 void *__copy_to = (void *) (to); \
 242 void *__copy_from = (void *) (from); \
 243 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
 244 __kernel_size_t __copy_res; \
 245 if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \
 246 __copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \
 247 } else __copy_res = __copy_size; \
 248 __copy_res; })
 249
 250 #define copy_from_user_ret(to,from,n,retval) ({ \
 251 if (copy_from_user(to,from,n)) \
 252         return retval; \
 253 })
 254
 255 #define __copy_from_user(to,from,n)             \
 256         __copy_user((void *)(to),               \
 257                     (void *)(from), n)
 258
 259 #define __copy_from_user_ret(to,from,n,retval) ({ \
 260 if (__copy_from_user(to,from,n)) \
 261         return retval; \
 262 })
 263
 264 #define __copy_to_user_inatomic __copy_to_user
 265 #define __copy_from_user_inatomic __copy_from_user
 266
 267 /* XXX: Not sure it works well..
 268    should be such that: 4byte clear and the rest. */
 269 extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
 270
 271 #define clear_user(addr,n) ({ \
 272 void * __cl_addr = (addr); \
 273 unsigned long __cl_size = (n); \
 274 if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
 275 __cl_size = __clear_user(__cl_addr, __cl_size); \
 276 __cl_size; })
 277
 278 extern int __strncpy_from_user(unsigned long __dest, unsigned long __src, int __count);
 279
 280 #define strncpy_from_user(dest,src,count) ({ \
 281 unsigned long __sfu_src = (unsigned long) (src); \
 282 int __sfu_count = (int) (count); \
 283 long __sfu_res = -EFAULT; \
 284 if(__access_ok(__sfu_src, __sfu_count)) { \
 285 __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
 286 } __sfu_res; })
 287
 288 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
 289
 290 /*
 291  * Return the size of a string (including the ending 0!)
 292  */
 293 extern long __strnlen_user(const char *__s, long __n);
 294
 295 extern __inline__ long strnlen_user(const char *s, long n)
 296 {
 297         if (!__addr_ok(s))
 298                 return 0;
 299         else
 300                 return __strnlen_user(s, n);
 301 }
 302
 303 struct exception_table_entry
 304 {
 305         unsigned long insn, fixup;
 306 };
 307
 308 #define ARCH_HAS_SEARCH_EXTABLE
 309
 310 /* If gcc inlines memset, it will use st.q instructions.  Therefore, we need
 311    kmalloc allocations to be 8-byte aligned.  Without this, the alignment
 312    becomes BYTE_PER_WORD i.e. only 4 (since sizeof(long)==sizeof(void*)==4 on
 313    sh64 at the moment). */
 314 #define ARCH_KMALLOC_MINALIGN 8
 315
 316 /* Returns 0 if exception not found and fixup.unit otherwise.  */
 317 extern unsigned long search_exception_table(unsigned long addr);
 318 extern const struct exception_table_entry *search_exception_tables (unsigned long addr);
 319
 320 #endif /* __ASM_SH64_UACCESS_H */