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_addr = (long)(ptr);                           \
 132         long __gu_err;                                          \
 133         __typeof(*(ptr)) __gu_val;                              \
 134         __asm__ ("":"=r" (__gu_val));                           \
 135         __asm__ ("":"=r" (__gu_err));                           \
 136         __get_user_size((void *)&__gu_val, __gu_addr, (size), __gu_err); \
 137         (x) = (__typeof__(*(ptr))) __gu_val;                    \
 138         __gu_err;                                               \
 139 })
 140
 141 #define __get_user_check(x,ptr,size)                            \
 142 ({                                                              \
 143         long __gu_addr = (long)(ptr);                           \
 144         long __gu_err = -EFAULT;                                \
 145         __typeof(*(ptr)) __gu_val;                              \
 146         __asm__ ("":"=r" (__gu_val));                           \
 147         __asm__ ("":"=r" (__gu_err));                           \
 148         if (__access_ok(__gu_addr, (size)))                     \
 149                 __get_user_size((void *)&__gu_val, __gu_addr, (size), __gu_err); \
 150         (x) = (__typeof__(*(ptr))) __gu_val;                    \
 151         __gu_err;                                               \
 152 })
 153
 154 extern long __get_user_asm_b(void *, long);
 155 extern long __get_user_asm_w(void *, long);
 156 extern long __get_user_asm_l(void *, long);
 157 extern long __get_user_asm_q(void *, long);
 158 extern void __get_user_unknown(void);
 159
 160 #define __put_user_size(x,ptr,size,retval)                      \
 161 do {                                                            \
 162         retval = 0;                                             \
 163         switch (size) {                                         \
 164         case 1:                                                 \
 165                 retval = __put_user_asm_b(x, ptr);              \
 166                 break;                                          \
 167         case 2:                                                 \
 168                 retval = __put_user_asm_w(x, ptr);              \
 169                 break;                                          \
 170         case 4:                                                 \
 171                 retval = __put_user_asm_l(x, ptr);              \
 172                 break;                                          \
 173         case 8:                                                 \
 174                 retval = __put_user_asm_q(x, ptr);              \
 175                 break;                                          \
 176         default:                                                \
 177                 __put_user_unknown();                           \
 178         }                                                       \
 179 } while (0)
 180
 181 #define __put_user_nocheck(x,ptr,size)                          \
 182 ({                                                              \
 183         long __pu_err;                                          \
 184         __typeof__(*(ptr)) __pu_val = (x);                      \
 185         __put_user_size((void *)&__pu_val, (long)(ptr), (size), __pu_err); \
 186         __pu_err;                                               \
 187 })
 188
 189 #define __put_user_check(x,ptr,size)                            \
 190 ({                                                              \
 191         long __pu_err = -EFAULT;                                \
 192         long __pu_addr = (long)(ptr);                           \
 193         __typeof__(*(ptr)) __pu_val = (x);                      \
 194                                                                 \
 195         if (__access_ok(__pu_addr, (size)))                     \
 196                 __put_user_size((void *)&__pu_val, __pu_addr, (size), __pu_err);\
 197         __pu_err;                                               \
 198 })
 199
 200 extern long __put_user_asm_b(void *, long);
 201 extern long __put_user_asm_w(void *, long);
 202 extern long __put_user_asm_l(void *, long);
 203 extern long __put_user_asm_q(void *, long);
 204 extern void __put_user_unknown(void);
 205
 206 \f
 207 /* Generic arbitrary sized copy.  */
 208 /* Return the number of bytes NOT copied */
 209 /* XXX: should be such that: 4byte and the rest. */
 210 extern __kernel_size_t __copy_user(void *__to, const void *__from, __kernel_size_t __n);
 211
 212 #define copy_to_user(to,from,n) ({ \
 213 void *__copy_to = (void *) (to); \
 214 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
 215 __kernel_size_t __copy_res; \
 216 if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \
 217 __copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \
 218 } else __copy_res = __copy_size; \
 219 __copy_res; })
 220
 221 #define copy_to_user_ret(to,from,n,retval) ({ \
 222 if (copy_to_user(to,from,n)) \
 223         return retval; \
 224 })
 225
 226 #define __copy_to_user(to,from,n)               \
 227         __copy_user((void *)(to),               \
 228                     (void *)(from), n)
 229
 230 #define __copy_to_user_ret(to,from,n,retval) ({ \
 231 if (__copy_to_user(to,from,n)) \
 232         return retval; \
 233 })
 234
 235 #define copy_from_user(to,from,n) ({ \
 236 void *__copy_to = (void *) (to); \
 237 void *__copy_from = (void *) (from); \
 238 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
 239 __kernel_size_t __copy_res; \
 240 if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \
 241 __copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \
 242 } else __copy_res = __copy_size; \
 243 __copy_res; })
 244
 245 #define copy_from_user_ret(to,from,n,retval) ({ \
 246 if (copy_from_user(to,from,n)) \
 247         return retval; \
 248 })
 249
 250 #define __copy_from_user(to,from,n)             \
 251         __copy_user((void *)(to),               \
 252                     (void *)(from), n)
 253
 254 #define __copy_from_user_ret(to,from,n,retval) ({ \
 255 if (__copy_from_user(to,from,n)) \
 256         return retval; \
 257 })
 258
 259 #define __copy_to_user_inatomic __copy_to_user
 260 #define __copy_from_user_inatomic __copy_from_user
 261
 262 /* XXX: Not sure it works well..
 263    should be such that: 4byte clear and the rest. */
 264 extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
 265
 266 #define clear_user(addr,n) ({ \
 267 void * __cl_addr = (addr); \
 268 unsigned long __cl_size = (n); \
 269 if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
 270 __cl_size = __clear_user(__cl_addr, __cl_size); \
 271 __cl_size; })
 272
 273 extern int __strncpy_from_user(unsigned long __dest, unsigned long __src, int __count);
 274
 275 #define strncpy_from_user(dest,src,count) ({ \
 276 unsigned long __sfu_src = (unsigned long) (src); \
 277 int __sfu_count = (int) (count); \
 278 long __sfu_res = -EFAULT; \
 279 if(__access_ok(__sfu_src, __sfu_count)) { \
 280 __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
 281 } __sfu_res; })
 282
 283 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
 284
 285 /*
 286  * Return the size of a string (including the ending 0!)
 287  */
 288 extern long __strnlen_user(const char *__s, long __n);
 289
 290 static inline long strnlen_user(const char *s, long n)
 291 {
 292         if (!__addr_ok(s))
 293                 return 0;
 294         else
 295                 return __strnlen_user(s, n);
 296 }
 297
 298 struct exception_table_entry
 299 {
 300         unsigned long insn, fixup;
 301 };
 302
 303 #define ARCH_HAS_SEARCH_EXTABLE
 304
 305 /* If gcc inlines memset, it will use st.q instructions.  Therefore, we need
 306    kmalloc allocations to be 8-byte aligned.  Without this, the alignment
 307    becomes BYTE_PER_WORD i.e. only 4 (since sizeof(long)==sizeof(void*)==4 on
 308    sh64 at the moment). */
 309 #define ARCH_KMALLOC_MINALIGN 8
 310
 311 /*
 312  * We want 8-byte alignment for the slab caches as well, otherwise we have
 313  * the same BYTES_PER_WORD (sizeof(void *)) min align in kmem_cache_create().
 314  */
 315 #define ARCH_SLAB_MINALIGN 8
 316
 317 /* Returns 0 if exception not found and fixup.unit otherwise.  */
 318 extern unsigned long search_exception_table(unsigned long addr);
 319 extern const struct exception_table_entry *search_exception_tables (unsigned long addr);
 320
 321 #endif /* __ASM_SH64_UACCESS_H */