arch/x86/include/asm/uaccess.h

   1 #ifndef _ASM_X86_UACCESS_H
   2 #define _ASM_X86_UACCESS_H
   3 /*
   4  * User space memory access functions
   5  */
   6 #include <linux/errno.h>
   7 #include <linux/compiler.h>
   8 #include <linux/thread_info.h>
   9 #include <linux/string.h>
  10 #include <asm/asm.h>
  11 #include <asm/page.h>
  12
  13 #define VERIFY_READ 0
  14 #define VERIFY_WRITE 1
  15
  16 /*
  17  * The fs value determines whether argument validity checking should be
  18  * performed or not.  If get_fs() == USER_DS, checking is performed, with
  19  * get_fs() == KERNEL_DS, checking is bypassed.
  20  *
  21  * For historical reasons, these macros are grossly misnamed.
  22  */
  23
  24 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
  25
  26 #define KERNEL_DS       MAKE_MM_SEG(-1UL)
  27 #define USER_DS         MAKE_MM_SEG(TASK_SIZE_MAX)
  28
  29 #define get_ds()        (KERNEL_DS)
  30 #define get_fs()        (current_thread_info()->addr_limit)
  31 #define set_fs(x)       (current_thread_info()->addr_limit = (x))
  32
  33 #define segment_eq(a, b)        ((a).seg == (b).seg)
  34
  35 #define __addr_ok(addr)                                 \
  36         ((unsigned long __force)(addr) <                \
  37          (current_thread_info()->addr_limit.seg))
  38
  39 /*
  40  * Test whether a block of memory is a valid user space address.
  41  * Returns 0 if the range is valid, nonzero otherwise.
  42  *
  43  * This is equivalent to the following test:
  44  * (u33)addr + (u33)size > (u33)current->addr_limit.seg (u65 for x86_64)
  45  *
  46  * This needs 33-bit (65-bit for x86_64) arithmetic. We have a carry...
  47  */
  48
  49 #define __range_not_ok(addr, size)                                      \
  50 ({                                                                      \
  51         unsigned long flag, roksum;                                     \
  52         __chk_user_ptr(addr);                                           \
  53         asm("add %3,%1 ; sbb %0,%0 ; cmp %1,%4 ; sbb $0,%0"             \
  54             : "=&r" (flag), "=r" (roksum)                               \
  55             : "1" (addr), "g" ((long)(size)),                           \
  56               "rm" (current_thread_info()->addr_limit.seg));            \
  57         flag;                                                           \
  58 })
  59
  60 /**
  61  * access_ok: - Checks if a user space pointer is valid
  62  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
  63  *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
  64  *        to write to a block, it is always safe to read from it.
  65  * @addr: User space pointer to start of block to check
  66  * @size: Size of block to check
  67  *
  68  * Context: User context only.  This function may sleep.
  69  *
  70  * Checks if a pointer to a block of memory in user space is valid.
  71  *
  72  * Returns true (nonzero) if the memory block may be valid, false (zero)
  73  * if it is definitely invalid.
  74  *
  75  * Note that, depending on architecture, this function probably just
  76  * checks that the pointer is in the user space range - after calling
  77  * this function, memory access functions may still return -EFAULT.
  78  */
  79 #define access_ok(type, addr, size) (likely(__range_not_ok(addr, size) == 0))
  80
  81 /*
  82  * The exception table consists of pairs of addresses relative to the
  83  * exception table enty itself: the first is the address of an
  84  * instruction that is allowed to fault, and the second is the address
  85  * at which the program should continue.  No registers are modified,
  86  * so it is entirely up to the continuation code to figure out what to
  87  * do.
  88  *
  89  * All the routines below use bits of fixup code that are out of line
  90  * with the main instruction path.  This means when everything is well,
  91  * we don't even have to jump over them.  Further, they do not intrude
  92  * on our cache or tlb entries.
  93  */
  94
  95 struct exception_table_entry {
  96         int insn, fixup;
  97 };
  98 /* This is not the generic standard exception_table_entry format */
  99 #define ARCH_HAS_SORT_EXTABLE
 100 #define ARCH_HAS_SEARCH_EXTABLE
 101
 102 extern int fixup_exception(struct pt_regs *regs);
 103 extern int early_fixup_exception(unsigned long *ip);
 104
 105 /*
 106  * These are the main single-value transfer routines.  They automatically
 107  * use the right size if we just have the right pointer type.
 108  *
 109  * This gets kind of ugly. We want to return _two_ values in "get_user()"
 110  * and yet we don't want to do any pointers, because that is too much
 111  * of a performance impact. Thus we have a few rather ugly macros here,
 112  * and hide all the ugliness from the user.
 113  *
 114  * The "__xxx" versions of the user access functions are versions that
 115  * do not verify the address space, that must have been done previously
 116  * with a separate "access_ok()" call (this is used when we do multiple
 117  * accesses to the same area of user memory).
 118  */
 119
 120 extern int __get_user_1(void);
 121 extern int __get_user_2(void);
 122 extern int __get_user_4(void);
 123 extern int __get_user_8(void);
 124 extern int __get_user_bad(void);
 125
 126 #define __get_user_x(size, ret, x, ptr)               \
 127         asm volatile("call __get_user_" #size         \
 128                      : "=a" (ret), "=d" (x)           \
 129                      : "0" (ptr))                     \
 130
 131 /* Careful: we have to cast the result to the type of the pointer
 132  * for sign reasons */
 133
 134 /**
 135  * get_user: - Get a simple variable from user space.
 136  * @x:   Variable to store result.
 137  * @ptr: Source address, in user space.
 138  *
 139  * Context: User context only.  This function may sleep.
 140  *
 141  * This macro copies a single simple variable from user space to kernel
 142  * space.  It supports simple types like char and int, but not larger
 143  * data types like structures or arrays.
 144  *
 145  * @ptr must have pointer-to-simple-variable type, and the result of
 146  * dereferencing @ptr must be assignable to @x without a cast.
 147  *
 148  * Returns zero on success, or -EFAULT on error.
 149  * On error, the variable @x is set to zero.
 150  */
 151 #ifdef CONFIG_X86_32
 152 #define __get_user_8(__ret_gu, __val_gu, ptr)                           \
 153                 __get_user_x(X, __ret_gu, __val_gu, ptr)
 154 #else
 155 #define __get_user_8(__ret_gu, __val_gu, ptr)                           \
 156                 __get_user_x(8, __ret_gu, __val_gu, ptr)
 157 #endif
 158
 159 #define get_user(x, ptr)                                                \
 160 ({                                                                      \
 161         int __ret_gu;                                                   \
 162         unsigned long __val_gu;                                         \
 163         __chk_user_ptr(ptr);                                            \
 164         might_fault();                                                  \
 165         switch (sizeof(*(ptr))) {                                       \
 166         case 1:                                                         \
 167                 __get_user_x(1, __ret_gu, __val_gu, ptr);               \
 168                 break;                                                  \
 169         case 2:                                                         \
 170                 __get_user_x(2, __ret_gu, __val_gu, ptr);               \
 171                 break;                                                  \
 172         case 4:                                                         \
 173                 __get_user_x(4, __ret_gu, __val_gu, ptr);               \
 174                 break;                                                  \
 175         case 8:                                                         \
 176                 __get_user_8(__ret_gu, __val_gu, ptr);                  \
 177                 break;                                                  \
 178         default:                                                        \
 179                 __get_user_x(X, __ret_gu, __val_gu, ptr);               \
 180                 break;                                                  \
 181         }                                                               \
 182         (x) = (__typeof__(*(ptr)))__val_gu;                             \
 183         __ret_gu;                                                       \
 184 })
 185
 186 #define __put_user_x(size, x, ptr, __ret_pu)                    \
 187         asm volatile("call __put_user_" #size : "=a" (__ret_pu) \
 188                      : "0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
 189
 190
 191
 192 #ifdef CONFIG_X86_32
 193 #define __put_user_asm_u64(x, addr, err, errret)                        \
 194         asm volatile("1:        movl %%eax,0(%2)\n"                     \
 195                      "2:        movl %%edx,4(%2)\n"                     \
 196                      "3:\n"                                             \
 197                      ".section .fixup,\"ax\"\n"                         \
 198                      "4:        movl %3,%0\n"                           \
 199                      "  jmp 3b\n"                                       \
 200                      ".previous\n"                                      \
 201                      _ASM_EXTABLE(1b, 4b)                               \
 202                      _ASM_EXTABLE(2b, 4b)                               \
 203                      : "=r" (err)                                       \
 204                      : "A" (x), "r" (addr), "i" (errret), "0" (err))
 205
 206 #define __put_user_asm_ex_u64(x, addr)                                  \
 207         asm volatile("1:        movl %%eax,0(%1)\n"                     \
 208                      "2:        movl %%edx,4(%1)\n"                     \
 209                      "3:\n"                                             \
 210                      _ASM_EXTABLE_EX(1b, 2b)                            \
 211                      _ASM_EXTABLE_EX(2b, 3b)                            \
 212                      : : "A" (x), "r" (addr))
 213
 214 #define __put_user_x8(x, ptr, __ret_pu)                         \
 215         asm volatile("call __put_user_8" : "=a" (__ret_pu)      \
 216                      : "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
 217 #else
 218 #define __put_user_asm_u64(x, ptr, retval, errret) \
 219         __put_user_asm(x, ptr, retval, "q", "", "er", errret)
 220 #define __put_user_asm_ex_u64(x, addr)  \
 221         __put_user_asm_ex(x, addr, "q", "", "er")
 222 #define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu)
 223 #endif
 224
 225 extern void __put_user_bad(void);
 226
 227 /*
 228  * Strange magic calling convention: pointer in %ecx,
 229  * value in %eax(:%edx), return value in %eax. clobbers %rbx
 230  */
 231 extern void __put_user_1(void);
 232 extern void __put_user_2(void);
 233 extern void __put_user_4(void);
 234 extern void __put_user_8(void);
 235
 236 #ifdef CONFIG_X86_WP_WORKS_OK
 237
 238 /**
 239  * put_user: - Write a simple value into user space.
 240  * @x:   Value to copy to user space.
 241  * @ptr: Destination address, in user space.
 242  *
 243  * Context: User context only.  This function may sleep.
 244  *
 245  * This macro copies a single simple value from kernel space to user
 246  * space.  It supports simple types like char and int, but not larger
 247  * data types like structures or arrays.
 248  *
 249  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 250  * to the result of dereferencing @ptr.
 251  *
 252  * Returns zero on success, or -EFAULT on error.
 253  */
 254 #define put_user(x, ptr)                                        \
 255 ({                                                              \
 256         int __ret_pu;                                           \
 257         __typeof__(*(ptr)) __pu_val;                            \
 258         __chk_user_ptr(ptr);                                    \
 259         might_fault();                                          \
 260         __pu_val = x;                                           \
 261         switch (sizeof(*(ptr))) {                               \
 262         case 1:                                                 \
 263                 __put_user_x(1, __pu_val, ptr, __ret_pu);       \
 264                 break;                                          \
 265         case 2:                                                 \
 266                 __put_user_x(2, __pu_val, ptr, __ret_pu);       \
 267                 break;                                          \
 268         case 4:                                                 \
 269                 __put_user_x(4, __pu_val, ptr, __ret_pu);       \
 270                 break;                                          \
 271         case 8:                                                 \
 272                 __put_user_x8(__pu_val, ptr, __ret_pu);         \
 273                 break;                                          \
 274         default:                                                \
 275                 __put_user_x(X, __pu_val, ptr, __ret_pu);       \
 276                 break;                                          \
 277         }                                                       \
 278         __ret_pu;                                               \
 279 })
 280
 281 #define __put_user_size(x, ptr, size, retval, errret)                   \
 282 do {                                                                    \
 283         retval = 0;                                                     \
 284         __chk_user_ptr(ptr);                                            \
 285         switch (size) {                                                 \
 286         case 1:                                                         \
 287                 __put_user_asm(x, ptr, retval, "b", "b", "iq", errret); \
 288                 break;                                                  \
 289         case 2:                                                         \
 290                 __put_user_asm(x, ptr, retval, "w", "w", "ir", errret); \
 291                 break;                                                  \
 292         case 4:                                                         \
 293                 __put_user_asm(x, ptr, retval, "l", "k", "ir", errret); \
 294                 break;                                                  \
 295         case 8:                                                         \
 296                 __put_user_asm_u64((__typeof__(*ptr))(x), ptr, retval,  \
 297                                    errret);                             \
 298                 break;                                                  \
 299         default:                                                        \
 300                 __put_user_bad();                                       \
 301         }                                                               \
 302 } while (0)
 303
 304 #define __put_user_size_ex(x, ptr, size)                                \
 305 do {                                                                    \
 306         __chk_user_ptr(ptr);                                            \
 307         switch (size) {                                                 \
 308         case 1:                                                         \
 309                 __put_user_asm_ex(x, ptr, "b", "b", "iq");              \
 310                 break;                                                  \
 311         case 2:                                                         \
 312                 __put_user_asm_ex(x, ptr, "w", "w", "ir");              \
 313                 break;                                                  \
 314         case 4:                                                         \
 315                 __put_user_asm_ex(x, ptr, "l", "k", "ir");              \
 316                 break;                                                  \
 317         case 8:                                                         \
 318                 __put_user_asm_ex_u64((__typeof__(*ptr))(x), ptr);      \
 319                 break;                                                  \
 320         default:                                                        \
 321                 __put_user_bad();                                       \
 322         }                                                               \
 323 } while (0)
 324
 325 #else
 326
 327 #define __put_user_size(x, ptr, size, retval, errret)                   \
 328 do {                                                                    \
 329         __typeof__(*(ptr))__pus_tmp = x;                                \
 330         retval = 0;                                                     \
 331                                                                         \
 332         if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0))    \
 333                 retval = errret;                                        \
 334 } while (0)
 335
 336 #define put_user(x, ptr)                                        \
 337 ({                                                              \
 338         int __ret_pu;                                           \
 339         __typeof__(*(ptr))__pus_tmp = x;                        \
 340         __ret_pu = 0;                                           \
 341         if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp,         \
 342                                        sizeof(*(ptr))) != 0))   \
 343                 __ret_pu = -EFAULT;                             \
 344         __ret_pu;                                               \
 345 })
 346 #endif
 347
 348 #ifdef CONFIG_X86_32
 349 #define __get_user_asm_u64(x, ptr, retval, errret)      (x) = __get_user_bad()
 350 #define __get_user_asm_ex_u64(x, ptr)                   (x) = __get_user_bad()
 351 #else
 352 #define __get_user_asm_u64(x, ptr, retval, errret) \
 353          __get_user_asm(x, ptr, retval, "q", "", "=r", errret)
 354 #define __get_user_asm_ex_u64(x, ptr) \
 355          __get_user_asm_ex(x, ptr, "q", "", "=r")
 356 #endif
 357
 358 #define __get_user_size(x, ptr, size, retval, errret)                   \
 359 do {                                                                    \
 360         retval = 0;                                                     \
 361         __chk_user_ptr(ptr);                                            \
 362         switch (size) {                                                 \
 363         case 1:                                                         \
 364                 __get_user_asm(x, ptr, retval, "b", "b", "=q", errret); \
 365                 break;                                                  \
 366         case 2:                                                         \
 367                 __get_user_asm(x, ptr, retval, "w", "w", "=r", errret); \
 368                 break;                                                  \
 369         case 4:                                                         \
 370                 __get_user_asm(x, ptr, retval, "l", "k", "=r", errret); \
 371                 break;                                                  \
 372         case 8:                                                         \
 373                 __get_user_asm_u64(x, ptr, retval, errret);             \
 374                 break;                                                  \
 375         default:                                                        \
 376                 (x) = __get_user_bad();                                 \
 377         }                                                               \
 378 } while (0)
 379
 380 #define __get_user_asm(x, addr, err, itype, rtype, ltype, errret)       \
 381         asm volatile("1:        mov"itype" %2,%"rtype"1\n"              \
 382                      "2:\n"                                             \
 383                      ".section .fixup,\"ax\"\n"                         \
 384                      "3:        mov %3,%0\n"                            \
 385                      "  xor"itype" %"rtype"1,%"rtype"1\n"               \
 386                      "  jmp 2b\n"                                       \
 387                      ".previous\n"                                      \
 388                      _ASM_EXTABLE(1b, 3b)                               \
 389                      : "=r" (err), ltype(x)                             \
 390                      : "m" (__m(addr)), "i" (errret), "0" (err))
 391
 392 #define __get_user_size_ex(x, ptr, size)                                \
 393 do {                                                                    \
 394         __chk_user_ptr(ptr);                                            \
 395         switch (size) {                                                 \
 396         case 1:                                                         \
 397                 __get_user_asm_ex(x, ptr, "b", "b", "=q");              \
 398                 break;                                                  \
 399         case 2:                                                         \
 400                 __get_user_asm_ex(x, ptr, "w", "w", "=r");              \
 401                 break;                                                  \
 402         case 4:                                                         \
 403                 __get_user_asm_ex(x, ptr, "l", "k", "=r");              \
 404                 break;                                                  \
 405         case 8:                                                         \
 406                 __get_user_asm_ex_u64(x, ptr);                          \
 407                 break;                                                  \
 408         default:                                                        \
 409                 (x) = __get_user_bad();                                 \
 410         }                                                               \
 411 } while (0)
 412
 413 #define __get_user_asm_ex(x, addr, itype, rtype, ltype)                 \
 414         asm volatile("1:        mov"itype" %1,%"rtype"0\n"              \
 415                      "2:\n"                                             \
 416                      _ASM_EXTABLE_EX(1b, 2b)                            \
 417                      : ltype(x) : "m" (__m(addr)))
 418
 419 #define __put_user_nocheck(x, ptr, size)                        \
 420 ({                                                              \
 421         int __pu_err;                                           \
 422         __put_user_size((x), (ptr), (size), __pu_err, -EFAULT); \
 423         __pu_err;                                               \
 424 })
 425
 426 #define __get_user_nocheck(x, ptr, size)                                \
 427 ({                                                                      \
 428         int __gu_err;                                                   \
 429         unsigned long __gu_val;                                         \
 430         __get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT);    \
 431         (x) = (__force __typeof__(*(ptr)))__gu_val;                     \
 432         __gu_err;                                                       \
 433 })
 434
 435 /* FIXME: this hack is definitely wrong -AK */
 436 struct __large_struct { unsigned long buf[100]; };
 437 #define __m(x) (*(struct __large_struct __user *)(x))
 438
 439 /*
 440  * Tell gcc we read from memory instead of writing: this is because
 441  * we do not write to any memory gcc knows about, so there are no
 442  * aliasing issues.
 443  */
 444 #define __put_user_asm(x, addr, err, itype, rtype, ltype, errret)       \
 445         asm volatile("1:        mov"itype" %"rtype"1,%2\n"              \
 446                      "2:\n"                                             \
 447                      ".section .fixup,\"ax\"\n"                         \
 448                      "3:        mov %3,%0\n"                            \
 449                      "  jmp 2b\n"                                       \
 450                      ".previous\n"                                      \
 451                      _ASM_EXTABLE(1b, 3b)                               \
 452                      : "=r"(err)                                        \
 453                      : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err))
 454
 455 #define __put_user_asm_ex(x, addr, itype, rtype, ltype)                 \
 456         asm volatile("1:        mov"itype" %"rtype"0,%1\n"              \
 457                      "2:\n"                                             \
 458                      _ASM_EXTABLE_EX(1b, 2b)                            \
 459                      : : ltype(x), "m" (__m(addr)))
 460
 461 /*
 462  * uaccess_try and catch
 463  */
 464 #define uaccess_try     do {                                            \
 465         int prev_err = current_thread_info()->uaccess_err;              \
 466         current_thread_info()->uaccess_err = 0;                         \
 467         barrier();
 468
 469 #define uaccess_catch(err)                                              \
 470         (err) |= (current_thread_info()->uaccess_err ? -EFAULT : 0);    \
 471         current_thread_info()->uaccess_err = prev_err;                  \
 472 } while (0)
 473
 474 /**
 475  * __get_user: - Get a simple variable from user space, with less checking.
 476  * @x:   Variable to store result.
 477  * @ptr: Source address, in user space.
 478  *
 479  * Context: User context only.  This function may sleep.
 480  *
 481  * This macro copies a single simple variable from user space to kernel
 482  * space.  It supports simple types like char and int, but not larger
 483  * data types like structures or arrays.
 484  *
 485  * @ptr must have pointer-to-simple-variable type, and the result of
 486  * dereferencing @ptr must be assignable to @x without a cast.
 487  *
 488  * Caller must check the pointer with access_ok() before calling this
 489  * function.
 490  *
 491  * Returns zero on success, or -EFAULT on error.
 492  * On error, the variable @x is set to zero.
 493  */
 494
 495 #define __get_user(x, ptr)                                              \
 496         __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
 497
 498 /**
 499  * __put_user: - Write a simple value into user space, with less checking.
 500  * @x:   Value to copy to user space.
 501  * @ptr: Destination address, in user space.
 502  *
 503  * Context: User context only.  This function may sleep.
 504  *
 505  * This macro copies a single simple value from kernel space to user
 506  * space.  It supports simple types like char and int, but not larger
 507  * data types like structures or arrays.
 508  *
 509  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 510  * to the result of dereferencing @ptr.
 511  *
 512  * Caller must check the pointer with access_ok() before calling this
 513  * function.
 514  *
 515  * Returns zero on success, or -EFAULT on error.
 516  */
 517
 518 #define __put_user(x, ptr)                                              \
 519         __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
 520
 521 #define __get_user_unaligned __get_user
 522 #define __put_user_unaligned __put_user
 523
 524 /*
 525  * {get|put}_user_try and catch
 526  *
 527  * get_user_try {
 528  *      get_user_ex(...);
 529  * } get_user_catch(err)
 530  */
 531 #define get_user_try            uaccess_try
 532 #define get_user_catch(err)     uaccess_catch(err)
 533
 534 #define get_user_ex(x, ptr)     do {                                    \
 535         unsigned long __gue_val;                                        \
 536         __get_user_size_ex((__gue_val), (ptr), (sizeof(*(ptr))));       \
 537         (x) = (__force __typeof__(*(ptr)))__gue_val;                    \
 538 } while (0)
 539
 540 #ifdef CONFIG_X86_WP_WORKS_OK
 541
 542 #define put_user_try            uaccess_try
 543 #define put_user_catch(err)     uaccess_catch(err)
 544
 545 #define put_user_ex(x, ptr)                                             \
 546         __put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
 547
 548 #else /* !CONFIG_X86_WP_WORKS_OK */
 549
 550 #define put_user_try            do {            \
 551         int __uaccess_err = 0;
 552
 553 #define put_user_catch(err)                     \
 554         (err) |= __uaccess_err;                 \
 555 } while (0)
 556
 557 #define put_user_ex(x, ptr)     do {            \
 558         __uaccess_err |= __put_user(x, ptr);    \
 559 } while (0)
 560
 561 #endif /* CONFIG_X86_WP_WORKS_OK */
 562
 563 extern unsigned long
 564 copy_from_user_nmi(void *to, const void __user *from, unsigned long n);
 565 extern __must_check long
 566 strncpy_from_user(char *dst, const char __user *src, long count);
 567
 568 /*
 569  * movsl can be slow when source and dest are not both 8-byte aligned
 570  */
 571 #ifdef CONFIG_X86_INTEL_USERCOPY
 572 extern struct movsl_mask {
 573         int mask;
 574 } ____cacheline_aligned_in_smp movsl_mask;
 575 #endif
 576
 577 #define ARCH_HAS_NOCACHE_UACCESS 1
 578
 579 #ifdef CONFIG_X86_32
 580 # include "uaccess_32.h"
 581 #else
 582 # include "uaccess_64.h"
 583 #endif
 584
 585 #endif /* _ASM_X86_UACCESS_H */
 586