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 /*
  64  * Uh, these should become the main single-value transfer routines ...
  65  * They automatically use the right size if we just have the right
  66  * pointer type ...
  67  *
  68  * As MIPS uses the same address space for kernel and user data, we
  69  * can just do these as direct assignments.
  70  *
  71  * Careful to not
  72  * (a) re-use the arguments for side effects (sizeof is ok)
  73  * (b) require any knowledge of processes at this stage
  74  */
  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)))
  77
  78 /*
  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()")
  82  */
  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)))
  85
  86 /*
  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.
  90  */
  91
  92 #define put_user_ret(x,ptr,ret) ({ \
  93 if (put_user(x,ptr)) return ret; })
  94
  95 #define get_user_ret(x,ptr,ret) ({ \
  96 if (get_user(x,ptr)) return ret; })
  97
  98 #define __put_user_ret(x,ptr,ret) ({ \
  99 if (__put_user(x,ptr)) return ret; })
 100
 101 #define __get_user_ret(x,ptr,ret) ({ \
 102 if (__get_user(x,ptr)) return ret; })
 103
 104 struct __large_struct { unsigned long buf[100]; };
 105 #define __m(x) (*(struct __large_struct *)(x))
 106
 107 #define __get_user_size(x,ptr,size,retval)                      \
 108 do {                                                            \
 109         retval = 0;                                             \
 110         switch (size) {                                         \
 111         case 1:                                                 \
 112                 retval = __get_user_asm_b(x, ptr);              \
 113                 break;                                          \
 114         case 2:                                                 \
 115                 retval = __get_user_asm_w(x, ptr);              \
 116                 break;                                          \
 117         case 4:                                                 \
 118                 retval = __get_user_asm_l(x, ptr);              \
 119                 break;                                          \
 120         case 8:                                                 \
 121                 retval = __get_user_asm_q(x, ptr);              \
 122                 break;                                          \
 123         default:                                                \
 124                 __get_user_unknown();                           \
 125                 break;                                          \
 126         }                                                       \
 127 } while (0)
 128
 129 #define __get_user_nocheck(x,ptr,size)                          \
 130 ({                                                              \
 131         long __gu_err, __gu_val;                                \
 132         __get_user_size((void *)&__gu_val, (long)(ptr),         \
 133                         (size), __gu_err);                      \
 134         (x) = (__typeof__(*(ptr)))__gu_val;                     \
 135         __gu_err;                                               \
 136 })
 137
 138 #define __get_user_check(x,ptr,size)                            \
 139 ({                                                              \
 140         long __gu_addr = (long)(ptr);                           \
 141         long __gu_err = -EFAULT, __gu_val;                      \
 142         if (__access_ok(__gu_addr, (size)))                     \
 143                 __get_user_size((void *)&__gu_val, __gu_addr,   \
 144                                 (size), __gu_err);              \
 145         (x) = (__typeof__(*(ptr))) __gu_val;                    \
 146         __gu_err;                                               \
 147 })
 148
 149 extern long __get_user_asm_b(void *, long);
 150 extern long __get_user_asm_w(void *, long);
 151 extern long __get_user_asm_l(void *, long);
 152 extern long __get_user_asm_q(void *, long);
 153 extern void __get_user_unknown(void);
 154
 155 #define __put_user_size(x,ptr,size,retval)                      \
 156 do {                                                            \
 157         retval = 0;                                             \
 158         switch (size) {                                         \
 159         case 1:                                                 \
 160                 retval = __put_user_asm_b(x, ptr);              \
 161                 break;                                          \
 162         case 2:                                                 \
 163                 retval = __put_user_asm_w(x, ptr);              \
 164                 break;                                          \
 165         case 4:                                                 \
 166                 retval = __put_user_asm_l(x, ptr);              \
 167                 break;                                          \
 168         case 8:                                                 \
 169                 retval = __put_user_asm_q(x, ptr);              \
 170                 break;                                          \
 171         default:                                                \
 172                 __put_user_unknown();                           \
 173         }                                                       \
 174 } while (0)
 175
 176 #define __put_user_nocheck(x,ptr,size)                          \
 177 ({                                                              \
 178         long __pu_err;                                          \
 179         __typeof__(*(ptr)) __pu_val = (x);                      \
 180         __put_user_size((void *)&__pu_val, (long)(ptr), (size), __pu_err); \
 181         __pu_err;                                               \
 182 })
 183
 184 #define __put_user_check(x,ptr,size)                            \
 185 ({                                                              \
 186         long __pu_err = -EFAULT;                                \
 187         long __pu_addr = (long)(ptr);                           \
 188         __typeof__(*(ptr)) __pu_val = (x);                      \
 189                                                                 \
 190         if (__access_ok(__pu_addr, (size)))                     \
 191                 __put_user_size((void *)&__pu_val, __pu_addr, (size), __pu_err);\
 192         __pu_err;                                               \
 193 })
 194
 195 extern long __put_user_asm_b(void *, long);
 196 extern long __put_user_asm_w(void *, long);
 197 extern long __put_user_asm_l(void *, long);
 198 extern long __put_user_asm_q(void *, long);
 199 extern void __put_user_unknown(void);
 200
 201 \f
 202 /* Generic arbitrary sized copy.  */
 203 /* Return the number of bytes NOT copied */
 204 /* XXX: should be such that: 4byte and the rest. */
 205 extern __kernel_size_t __copy_user(void *__to, const void *__from, __kernel_size_t __n);
 206
 207 #define copy_to_user(to,from,n) ({ \
 208 void *__copy_to = (void *) (to); \
 209 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
 210 __kernel_size_t __copy_res; \
 211 if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \
 212 __copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \
 213 } else __copy_res = __copy_size; \
 214 __copy_res; })
 215
 216 #define copy_to_user_ret(to,from,n,retval) ({ \
 217 if (copy_to_user(to,from,n)) \
 218         return retval; \
 219 })
 220
 221 #define __copy_to_user(to,from,n)               \
 222         __copy_user((void *)(to),               \
 223                     (void *)(from), n)
 224
 225 #define __copy_to_user_ret(to,from,n,retval) ({ \
 226 if (__copy_to_user(to,from,n)) \
 227         return retval; \
 228 })
 229
 230 #define copy_from_user(to,from,n) ({ \
 231 void *__copy_to = (void *) (to); \
 232 void *__copy_from = (void *) (from); \
 233 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
 234 __kernel_size_t __copy_res; \
 235 if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \
 236 __copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \
 237 } else __copy_res = __copy_size; \
 238 __copy_res; })
 239
 240 #define copy_from_user_ret(to,from,n,retval) ({ \
 241 if (copy_from_user(to,from,n)) \
 242         return retval; \
 243 })
 244
 245 #define __copy_from_user(to,from,n)             \
 246         __copy_user((void *)(to),               \
 247                     (void *)(from), n)
 248
 249 #define __copy_from_user_ret(to,from,n,retval) ({ \
 250 if (__copy_from_user(to,from,n)) \
 251         return retval; \
 252 })
 253
 254 #define __copy_to_user_inatomic __copy_to_user
 255 #define __copy_from_user_inatomic __copy_from_user
 256
 257 /* XXX: Not sure it works well..
 258    should be such that: 4byte clear and the rest. */
 259 extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
 260
 261 #define clear_user(addr,n) ({ \
 262 void * __cl_addr = (addr); \
 263 unsigned long __cl_size = (n); \
 264 if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
 265 __cl_size = __clear_user(__cl_addr, __cl_size); \
 266 __cl_size; })
 267
 268 extern int __strncpy_from_user(unsigned long __dest, unsigned long __src, int __count);
 269
 270 #define strncpy_from_user(dest,src,count) ({ \
 271 unsigned long __sfu_src = (unsigned long) (src); \
 272 int __sfu_count = (int) (count); \
 273 long __sfu_res = -EFAULT; \
 274 if(__access_ok(__sfu_src, __sfu_count)) { \
 275 __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
 276 } __sfu_res; })
 277
 278 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
 279
 280 /*
 281  * Return the size of a string (including the ending 0!)
 282  */
 283 extern long __strnlen_user(const char *__s, long __n);
 284
 285 static inline long strnlen_user(const char *s, long n)
 286 {
 287         if (!__addr_ok(s))
 288                 return 0;
 289         else
 290                 return __strnlen_user(s, n);
 291 }
 292
 293 struct exception_table_entry
 294 {
 295         unsigned long insn, fixup;
 296 };
 297
 298 #define ARCH_HAS_SEARCH_EXTABLE
 299
 300 /* If gcc inlines memset, it will use st.q instructions.  Therefore, we need
 301    kmalloc allocations to be 8-byte aligned.  Without this, the alignment
 302    becomes BYTE_PER_WORD i.e. only 4 (since sizeof(long)==sizeof(void*)==4 on
 303    sh64 at the moment). */
 304 #define ARCH_KMALLOC_MINALIGN 8
 305
 306 /*
 307  * We want 8-byte alignment for the slab caches as well, otherwise we have
 308  * the same BYTES_PER_WORD (sizeof(void *)) min align in kmem_cache_create().
 309  */
 310 #define ARCH_SLAB_MINALIGN 8
 311
 312 /* Returns 0 if exception not found and fixup.unit otherwise.  */
 313 extern unsigned long search_exception_table(unsigned long addr);
 314 extern const struct exception_table_entry *search_exception_tables (unsigned long addr);
 315
 316 #endif /* __ASM_SH64_UACCESS_H */