arch/mips/include/asm/uaccess.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
   7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   8  * Copyright (C) 2007  Maciej W. Rozycki
   9  */
  10 #ifndef _ASM_UACCESS_H
  11 #define _ASM_UACCESS_H
  12
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/thread_info.h>
  16
  17 /*
  18  * The fs value determines whether argument validity checking should be
  19  * performed or not.  If get_fs() == USER_DS, checking is performed, with
  20  * get_fs() == KERNEL_DS, checking is bypassed.
  21  *
  22  * For historical reasons, these macros are grossly misnamed.
  23  */
  24 #ifdef CONFIG_32BIT
  25
  26 #define __UA_LIMIT      0x80000000UL
  27
  28 #define __UA_ADDR       ".word"
  29 #define __UA_LA         "la"
  30 #define __UA_ADDU       "addu"
  31 #define __UA_t0         "$8"
  32 #define __UA_t1         "$9"
  33
  34 #endif /* CONFIG_32BIT */
  35
  36 #ifdef CONFIG_64BIT
  37
  38 #define __UA_LIMIT      (- TASK_SIZE)
  39
  40 #define __UA_ADDR       ".dword"
  41 #define __UA_LA         "dla"
  42 #define __UA_ADDU       "daddu"
  43 #define __UA_t0         "$12"
  44 #define __UA_t1         "$13"
  45
  46 #endif /* CONFIG_64BIT */
  47
  48 /*
  49  * USER_DS is a bitmask that has the bits set that may not be set in a valid
  50  * userspace address.  Note that we limit 32-bit userspace to 0x7fff8000 but
  51  * the arithmetic we're doing only works if the limit is a power of two, so
  52  * we use 0x80000000 here on 32-bit kernels.  If a process passes an invalid
  53  * address in this range it's the process's problem, not ours :-)
  54  */
  55
  56 #define KERNEL_DS       ((mm_segment_t) { 0UL })
  57 #define USER_DS         ((mm_segment_t) { __UA_LIMIT })
  58
  59 #define VERIFY_READ    0
  60 #define VERIFY_WRITE   1
  61
  62 #define get_ds()        (KERNEL_DS)
  63 #define get_fs()        (current_thread_info()->addr_limit)
  64 #define set_fs(x)       (current_thread_info()->addr_limit = (x))
  65
  66 #define segment_eq(a, b)        ((a).seg == (b).seg)
  67
  68
  69 /*
  70  * Is a address valid? This does a straighforward calculation rather
  71  * than tests.
  72  *
  73  * Address valid if:
  74  *  - "addr" doesn't have any high-bits set
  75  *  - AND "size" doesn't have any high-bits set
  76  *  - AND "addr+size" doesn't have any high-bits set
  77  *  - OR we are in kernel mode.
  78  *
  79  * __ua_size() is a trick to avoid runtime checking of positive constant
  80  * sizes; for those we already know at compile time that the size is ok.
  81  */
  82 #define __ua_size(size)                                                 \
  83         ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
  84
  85 /*
  86  * access_ok: - Checks if a user space pointer is valid
  87  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
  88  *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
  89  *        to write to a block, it is always safe to read from it.
  90  * @addr: User space pointer to start of block to check
  91  * @size: Size of block to check
  92  *
  93  * Context: User context only.  This function may sleep.
  94  *
  95  * Checks if a pointer to a block of memory in user space is valid.
  96  *
  97  * Returns true (nonzero) if the memory block may be valid, false (zero)
  98  * if it is definitely invalid.
  99  *
 100  * Note that, depending on architecture, this function probably just
 101  * checks that the pointer is in the user space range - after calling
 102  * this function, memory access functions may still return -EFAULT.
 103  */
 104
 105 #define __access_mask get_fs().seg
 106
 107 #define __access_ok(addr, size, mask)                                                   \
 108 ({                                                                                      \
 109         const volatile void __user *__up = addr;                                        \
 110         unsigned long __addr = (unsigned long) __up;                                    \
 111         unsigned long __size = size;                                                    \
 112         unsigned long __mask = mask;                                                    \
 113         unsigned long __ok;                                                             \
 114                                                                                         \
 115         __ok = (signed long)(__mask & (__addr | (__addr + __size) |                     \
 116                 __ua_size(__size)));                                                    \
 117         __ok == 0;                                                                      \
 118 })
 119
 120 #define access_ok(type, addr, size)                                     \
 121         likely(__access_ok((addr), (size), __access_mask))
 122
 123 /*
 124  * put_user: - Write a simple value into user space.
 125  * @x:   Value to copy to user space.
 126  * @ptr: Destination address, in user space.
 127  *
 128  * Context: User context only.  This function may sleep.
 129  *
 130  * This macro copies a single simple value from kernel space to user
 131  * space.  It supports simple types like char and int, but not larger
 132  * data types like structures or arrays.
 133  *
 134  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 135  * to the result of dereferencing @ptr.
 136  *
 137  * Returns zero on success, or -EFAULT on error.
 138  */
 139 #define put_user(x,ptr) \
 140         __put_user_check((x), (ptr), sizeof(*(ptr)))
 141
 142 /*
 143  * get_user: - Get a simple variable from user space.
 144  * @x:   Variable to store result.
 145  * @ptr: Source address, in user space.
 146  *
 147  * Context: User context only.  This function may sleep.
 148  *
 149  * This macro copies a single simple variable from user space to kernel
 150  * space.  It supports simple types like char and int, but not larger
 151  * data types like structures or arrays.
 152  *
 153  * @ptr must have pointer-to-simple-variable type, and the result of
 154  * dereferencing @ptr must be assignable to @x without a cast.
 155  *
 156  * Returns zero on success, or -EFAULT on error.
 157  * On error, the variable @x is set to zero.
 158  */
 159 #define get_user(x,ptr) \
 160         __get_user_check((x), (ptr), sizeof(*(ptr)))
 161
 162 /*
 163  * __put_user: - Write a simple value into user space, with less checking.
 164  * @x:   Value to copy to user space.
 165  * @ptr: Destination address, in user space.
 166  *
 167  * Context: User context only.  This function may sleep.
 168  *
 169  * This macro copies a single simple value from kernel space to user
 170  * space.  It supports simple types like char and int, but not larger
 171  * data types like structures or arrays.
 172  *
 173  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 174  * to the result of dereferencing @ptr.
 175  *
 176  * Caller must check the pointer with access_ok() before calling this
 177  * function.
 178  *
 179  * Returns zero on success, or -EFAULT on error.
 180  */
 181 #define __put_user(x,ptr) \
 182         __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
 183
 184 /*
 185  * __get_user: - Get a simple variable from user space, with less checking.
 186  * @x:   Variable to store result.
 187  * @ptr: Source address, in user space.
 188  *
 189  * Context: User context only.  This function may sleep.
 190  *
 191  * This macro copies a single simple variable from user space to kernel
 192  * space.  It supports simple types like char and int, but not larger
 193  * data types like structures or arrays.
 194  *
 195  * @ptr must have pointer-to-simple-variable type, and the result of
 196  * dereferencing @ptr must be assignable to @x without a cast.
 197  *
 198  * Caller must check the pointer with access_ok() before calling this
 199  * function.
 200  *
 201  * Returns zero on success, or -EFAULT on error.
 202  * On error, the variable @x is set to zero.
 203  */
 204 #define __get_user(x,ptr) \
 205         __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
 206
 207 struct __large_struct { unsigned long buf[100]; };
 208 #define __m(x) (*(struct __large_struct __user *)(x))
 209
 210 /*
 211  * Yuck.  We need two variants, one for 64bit operation and one
 212  * for 32 bit mode and old iron.
 213  */
 214 #ifdef CONFIG_32BIT
 215 #define __GET_USER_DW(val, ptr) __get_user_asm_ll32(val, ptr)
 216 #endif
 217 #ifdef CONFIG_64BIT
 218 #define __GET_USER_DW(val, ptr) __get_user_asm(val, "ld", ptr)
 219 #endif
 220
 221 extern void __get_user_unknown(void);
 222
 223 #define __get_user_common(val, size, ptr)                               \
 224 do {                                                                    \
 225         switch (size) {                                                 \
 226         case 1: __get_user_asm(val, "lb", ptr); break;                  \
 227         case 2: __get_user_asm(val, "lh", ptr); break;                  \
 228         case 4: __get_user_asm(val, "lw", ptr); break;                  \
 229         case 8: __GET_USER_DW(val, ptr); break;                         \
 230         default: __get_user_unknown(); break;                           \
 231         }                                                               \
 232 } while (0)
 233
 234 #define __get_user_nocheck(x, ptr, size)                                \
 235 ({                                                                      \
 236         int __gu_err;                                                   \
 237                                                                         \
 238         __get_user_common((x), size, ptr);                              \
 239         __gu_err;                                                       \
 240 })
 241
 242 #define __get_user_check(x, ptr, size)                                  \
 243 ({                                                                      \
 244         int __gu_err = -EFAULT;                                         \
 245         const __typeof__(*(ptr)) __user * __gu_ptr = (ptr);             \
 246                                                                         \
 247         if (likely(access_ok(VERIFY_READ,  __gu_ptr, size)))            \
 248                 __get_user_common((x), size, __gu_ptr);                 \
 249                                                                         \
 250         __gu_err;                                                       \
 251 })
 252
 253 #define __get_user_asm(val, insn, addr)                                 \
 254 {                                                                       \
 255         long __gu_tmp;                                                  \
 256                                                                         \
 257         __asm__ __volatile__(                                           \
 258         "1:     " insn "        %1, %3                          \n"     \
 259         "2:                                                     \n"     \
 260         "       .section .fixup,\"ax\"                          \n"     \
 261         "3:     li      %0, %4                                  \n"     \
 262         "       j       2b                                      \n"     \
 263         "       .previous                                       \n"     \
 264         "       .section __ex_table,\"a\"                       \n"     \
 265         "       "__UA_ADDR "\t1b, 3b                            \n"     \
 266         "       .previous                                       \n"     \
 267         : "=r" (__gu_err), "=r" (__gu_tmp)                              \
 268         : "0" (0), "o" (__m(addr)), "i" (-EFAULT));                     \
 269                                                                         \
 270         (val) = (__typeof__(*(addr))) __gu_tmp;                         \
 271 }
 272
 273 /*
 274  * Get a long long 64 using 32 bit registers.
 275  */
 276 #define __get_user_asm_ll32(val, addr)                                  \
 277 {                                                                       \
 278         union {                                                         \
 279                 unsigned long long      l;                              \
 280                 __typeof__(*(addr))     t;                              \
 281         } __gu_tmp;                                                     \
 282                                                                         \
 283         __asm__ __volatile__(                                           \
 284         "1:     lw      %1, (%3)                                \n"     \
 285         "2:     lw      %D1, 4(%3)                              \n"     \
 286         "3:     .section        .fixup,\"ax\"                   \n"     \
 287         "4:     li      %0, %4                                  \n"     \
 288         "       move    %1, $0                                  \n"     \
 289         "       move    %D1, $0                                 \n"     \
 290         "       j       3b                                      \n"     \
 291         "       .previous                                       \n"     \
 292         "       .section        __ex_table,\"a\"                \n"     \
 293         "       " __UA_ADDR "   1b, 4b                          \n"     \
 294         "       " __UA_ADDR "   2b, 4b                          \n"     \
 295         "       .previous                                       \n"     \
 296         : "=r" (__gu_err), "=&r" (__gu_tmp.l)                           \
 297         : "0" (0), "r" (addr), "i" (-EFAULT));                          \
 298                                                                         \
 299         (val) = __gu_tmp.t;                                             \
 300 }
 301
 302 /*
 303  * Yuck.  We need two variants, one for 64bit operation and one
 304  * for 32 bit mode and old iron.
 305  */
 306 #ifdef CONFIG_32BIT
 307 #define __PUT_USER_DW(ptr) __put_user_asm_ll32(ptr)
 308 #endif
 309 #ifdef CONFIG_64BIT
 310 #define __PUT_USER_DW(ptr) __put_user_asm("sd", ptr)
 311 #endif
 312
 313 #define __put_user_nocheck(x, ptr, size)                                \
 314 ({                                                                      \
 315         __typeof__(*(ptr)) __pu_val;                                    \
 316         int __pu_err = 0;                                               \
 317                                                                         \
 318         __pu_val = (x);                                                 \
 319         switch (size) {                                                 \
 320         case 1: __put_user_asm("sb", ptr); break;                       \
 321         case 2: __put_user_asm("sh", ptr); break;                       \
 322         case 4: __put_user_asm("sw", ptr); break;                       \
 323         case 8: __PUT_USER_DW(ptr); break;                              \
 324         default: __put_user_unknown(); break;                           \
 325         }                                                               \
 326         __pu_err;                                                       \
 327 })
 328
 329 #define __put_user_check(x, ptr, size)                                  \
 330 ({                                                                      \
 331         __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
 332         __typeof__(*(ptr)) __pu_val = (x);                              \
 333         int __pu_err = -EFAULT;                                         \
 334                                                                         \
 335         if (likely(access_ok(VERIFY_WRITE,  __pu_addr, size))) {        \
 336                 switch (size) {                                         \
 337                 case 1: __put_user_asm("sb", __pu_addr); break;         \
 338                 case 2: __put_user_asm("sh", __pu_addr); break;         \
 339                 case 4: __put_user_asm("sw", __pu_addr); break;         \
 340                 case 8: __PUT_USER_DW(__pu_addr); break;                \
 341                 default: __put_user_unknown(); break;                   \
 342                 }                                                       \
 343         }                                                               \
 344         __pu_err;                                                       \
 345 })
 346
 347 #define __put_user_asm(insn, ptr)                                       \
 348 {                                                                       \
 349         __asm__ __volatile__(                                           \
 350         "1:     " insn "        %z2, %3         # __put_user_asm\n"     \
 351         "2:                                                     \n"     \
 352         "       .section        .fixup,\"ax\"                   \n"     \
 353         "3:     li      %0, %4                                  \n"     \
 354         "       j       2b                                      \n"     \
 355         "       .previous                                       \n"     \
 356         "       .section        __ex_table,\"a\"                \n"     \
 357         "       " __UA_ADDR "   1b, 3b                          \n"     \
 358         "       .previous                                       \n"     \
 359         : "=r" (__pu_err)                                               \
 360         : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)),                     \
 361           "i" (-EFAULT));                                               \
 362 }
 363
 364 #define __put_user_asm_ll32(ptr)                                        \
 365 {                                                                       \
 366         __asm__ __volatile__(                                           \
 367         "1:     sw      %2, (%3)        # __put_user_asm_ll32   \n"     \
 368         "2:     sw      %D2, 4(%3)                              \n"     \
 369         "3:                                                     \n"     \
 370         "       .section        .fixup,\"ax\"                   \n"     \
 371         "4:     li      %0, %4                                  \n"     \
 372         "       j       3b                                      \n"     \
 373         "       .previous                                       \n"     \
 374         "       .section        __ex_table,\"a\"                \n"     \
 375         "       " __UA_ADDR "   1b, 4b                          \n"     \
 376         "       " __UA_ADDR "   2b, 4b                          \n"     \
 377         "       .previous"                                              \
 378         : "=r" (__pu_err)                                               \
 379         : "0" (0), "r" (__pu_val), "r" (ptr),                           \
 380           "i" (-EFAULT));                                               \
 381 }
 382
 383 extern void __put_user_unknown(void);
 384
 385 /*
 386  * put_user_unaligned: - Write a simple value into user space.
 387  * @x:   Value to copy to user space.
 388  * @ptr: Destination address, in user space.
 389  *
 390  * Context: User context only.  This function may sleep.
 391  *
 392  * This macro copies a single simple value from kernel space to user
 393  * space.  It supports simple types like char and int, but not larger
 394  * data types like structures or arrays.
 395  *
 396  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 397  * to the result of dereferencing @ptr.
 398  *
 399  * Returns zero on success, or -EFAULT on error.
 400  */
 401 #define put_user_unaligned(x,ptr)       \
 402         __put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
 403
 404 /*
 405  * get_user_unaligned: - Get a simple variable from user space.
 406  * @x:   Variable to store result.
 407  * @ptr: Source address, in user space.
 408  *
 409  * Context: User context only.  This function may sleep.
 410  *
 411  * This macro copies a single simple variable from user space to kernel
 412  * space.  It supports simple types like char and int, but not larger
 413  * data types like structures or arrays.
 414  *
 415  * @ptr must have pointer-to-simple-variable type, and the result of
 416  * dereferencing @ptr must be assignable to @x without a cast.
 417  *
 418  * Returns zero on success, or -EFAULT on error.
 419  * On error, the variable @x is set to zero.
 420  */
 421 #define get_user_unaligned(x,ptr) \
 422         __get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
 423
 424 /*
 425  * __put_user_unaligned: - Write a simple value into user space, with less checking.
 426  * @x:   Value to copy to user space.
 427  * @ptr: Destination address, in user space.
 428  *
 429  * Context: User context only.  This function may sleep.
 430  *
 431  * This macro copies a single simple value from kernel space to user
 432  * space.  It supports simple types like char and int, but not larger
 433  * data types like structures or arrays.
 434  *
 435  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 436  * to the result of dereferencing @ptr.
 437  *
 438  * Caller must check the pointer with access_ok() before calling this
 439  * function.
 440  *
 441  * Returns zero on success, or -EFAULT on error.
 442  */
 443 #define __put_user_unaligned(x,ptr) \
 444         __put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
 445
 446 /*
 447  * __get_user_unaligned: - Get a simple variable from user space, with less checking.
 448  * @x:   Variable to store result.
 449  * @ptr: Source address, in user space.
 450  *
 451  * Context: User context only.  This function may sleep.
 452  *
 453  * This macro copies a single simple variable from user space to kernel
 454  * space.  It supports simple types like char and int, but not larger
 455  * data types like structures or arrays.
 456  *
 457  * @ptr must have pointer-to-simple-variable type, and the result of
 458  * dereferencing @ptr must be assignable to @x without a cast.
 459  *
 460  * Caller must check the pointer with access_ok() before calling this
 461  * function.
 462  *
 463  * Returns zero on success, or -EFAULT on error.
 464  * On error, the variable @x is set to zero.
 465  */
 466 #define __get_user_unaligned(x,ptr) \
 467         __get_user__unalignednocheck((x),(ptr),sizeof(*(ptr)))
 468
 469 /*
 470  * Yuck.  We need two variants, one for 64bit operation and one
 471  * for 32 bit mode and old iron.
 472  */
 473 #ifdef CONFIG_32BIT
 474 #define __GET_USER_UNALIGNED_DW(val, ptr)                               \
 475         __get_user_unaligned_asm_ll32(val, ptr)
 476 #endif
 477 #ifdef CONFIG_64BIT
 478 #define __GET_USER_UNALIGNED_DW(val, ptr)                               \
 479         __get_user_unaligned_asm(val, "uld", ptr)
 480 #endif
 481
 482 extern void __get_user_unaligned_unknown(void);
 483
 484 #define __get_user_unaligned_common(val, size, ptr)                     \
 485 do {                                                                    \
 486         switch (size) {                                                 \
 487         case 1: __get_user_asm(val, "lb", ptr); break;                  \
 488         case 2: __get_user_unaligned_asm(val, "ulh", ptr); break;       \
 489         case 4: __get_user_unaligned_asm(val, "ulw", ptr); break;       \
 490         case 8: __GET_USER_UNALIGNED_DW(val, ptr); break;               \
 491         default: __get_user_unaligned_unknown(); break;                 \
 492         }                                                               \
 493 } while (0)
 494
 495 #define __get_user_unaligned_nocheck(x,ptr,size)                        \
 496 ({                                                                      \
 497         int __gu_err;                                                   \
 498                                                                         \
 499         __get_user_unaligned_common((x), size, ptr);                    \
 500         __gu_err;                                                       \
 501 })
 502
 503 #define __get_user_unaligned_check(x,ptr,size)                          \
 504 ({                                                                      \
 505         int __gu_err = -EFAULT;                                         \
 506         const __typeof__(*(ptr)) __user * __gu_ptr = (ptr);             \
 507                                                                         \
 508         if (likely(access_ok(VERIFY_READ,  __gu_ptr, size)))            \
 509                 __get_user_unaligned_common((x), size, __gu_ptr);       \
 510                                                                         \
 511         __gu_err;                                                       \
 512 })
 513
 514 #define __get_user_unaligned_asm(val, insn, addr)                       \
 515 {                                                                       \
 516         long __gu_tmp;                                                  \
 517                                                                         \
 518         __asm__ __volatile__(                                           \
 519         "1:     " insn "        %1, %3                          \n"     \
 520         "2:                                                     \n"     \
 521         "       .section .fixup,\"ax\"                          \n"     \
 522         "3:     li      %0, %4                                  \n"     \
 523         "       j       2b                                      \n"     \
 524         "       .previous                                       \n"     \
 525         "       .section __ex_table,\"a\"                       \n"     \
 526         "       "__UA_ADDR "\t1b, 3b                            \n"     \
 527         "       "__UA_ADDR "\t1b + 4, 3b                        \n"     \
 528         "       .previous                                       \n"     \
 529         : "=r" (__gu_err), "=r" (__gu_tmp)                              \
 530         : "0" (0), "o" (__m(addr)), "i" (-EFAULT));                     \
 531                                                                         \
 532         (val) = (__typeof__(*(addr))) __gu_tmp;                         \
 533 }
 534
 535 /*
 536  * Get a long long 64 using 32 bit registers.
 537  */
 538 #define __get_user_unaligned_asm_ll32(val, addr)                        \
 539 {                                                                       \
 540         unsigned long long __gu_tmp;                                    \
 541                                                                         \
 542         __asm__ __volatile__(                                           \
 543         "1:     ulw     %1, (%3)                                \n"     \
 544         "2:     ulw     %D1, 4(%3)                              \n"     \
 545         "       move    %0, $0                                  \n"     \
 546         "3:     .section        .fixup,\"ax\"                   \n"     \
 547         "4:     li      %0, %4                                  \n"     \
 548         "       move    %1, $0                                  \n"     \
 549         "       move    %D1, $0                                 \n"     \
 550         "       j       3b                                      \n"     \
 551         "       .previous                                       \n"     \
 552         "       .section        __ex_table,\"a\"                \n"     \
 553         "       " __UA_ADDR "   1b, 4b                          \n"     \
 554         "       " __UA_ADDR "   1b + 4, 4b                      \n"     \
 555         "       " __UA_ADDR "   2b, 4b                          \n"     \
 556         "       " __UA_ADDR "   2b + 4, 4b                      \n"     \
 557         "       .previous                                       \n"     \
 558         : "=r" (__gu_err), "=&r" (__gu_tmp)                             \
 559         : "0" (0), "r" (addr), "i" (-EFAULT));                          \
 560         (val) = (__typeof__(*(addr))) __gu_tmp;                         \
 561 }
 562
 563 /*
 564  * Yuck.  We need two variants, one for 64bit operation and one
 565  * for 32 bit mode and old iron.
 566  */
 567 #ifdef CONFIG_32BIT
 568 #define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
 569 #endif
 570 #ifdef CONFIG_64BIT
 571 #define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
 572 #endif
 573
 574 #define __put_user_unaligned_nocheck(x,ptr,size)                        \
 575 ({                                                                      \
 576         __typeof__(*(ptr)) __pu_val;                                    \
 577         int __pu_err = 0;                                               \
 578                                                                         \
 579         __pu_val = (x);                                                 \
 580         switch (size) {                                                 \
 581         case 1: __put_user_asm("sb", ptr); break;                       \
 582         case 2: __put_user_unaligned_asm("ush", ptr); break;            \
 583         case 4: __put_user_unaligned_asm("usw", ptr); break;            \
 584         case 8: __PUT_USER_UNALIGNED_DW(ptr); break;                    \
 585         default: __put_user_unaligned_unknown(); break;                 \
 586         }                                                               \
 587         __pu_err;                                                       \
 588 })
 589
 590 #define __put_user_unaligned_check(x,ptr,size)                          \
 591 ({                                                                      \
 592         __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
 593         __typeof__(*(ptr)) __pu_val = (x);                              \
 594         int __pu_err = -EFAULT;                                         \
 595                                                                         \
 596         if (likely(access_ok(VERIFY_WRITE,  __pu_addr, size))) {        \
 597                 switch (size) {                                         \
 598                 case 1: __put_user_asm("sb", __pu_addr); break;         \
 599                 case 2: __put_user_unaligned_asm("ush", __pu_addr); break; \
 600                 case 4: __put_user_unaligned_asm("usw", __pu_addr); break; \
 601                 case 8: __PUT_USER_UNALGINED_DW(__pu_addr); break;      \
 602                 default: __put_user_unaligned_unknown(); break;         \
 603                 }                                                       \
 604         }                                                               \
 605         __pu_err;                                                       \
 606 })
 607
 608 #define __put_user_unaligned_asm(insn, ptr)                             \
 609 {                                                                       \
 610         __asm__ __volatile__(                                           \
 611         "1:     " insn "        %z2, %3         # __put_user_unaligned_asm\n" \
 612         "2:                                                     \n"     \
 613         "       .section        .fixup,\"ax\"                   \n"     \
 614         "3:     li      %0, %4                                  \n"     \
 615         "       j       2b                                      \n"     \
 616         "       .previous                                       \n"     \
 617         "       .section        __ex_table,\"a\"                \n"     \
 618         "       " __UA_ADDR "   1b, 3b                          \n"     \
 619         "       .previous                                       \n"     \
 620         : "=r" (__pu_err)                                               \
 621         : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)),                     \
 622           "i" (-EFAULT));                                               \
 623 }
 624
 625 #define __put_user_unaligned_asm_ll32(ptr)                              \
 626 {                                                                       \
 627         __asm__ __volatile__(                                           \
 628         "1:     sw      %2, (%3)        # __put_user_unaligned_asm_ll32 \n" \
 629         "2:     sw      %D2, 4(%3)                              \n"     \
 630         "3:                                                     \n"     \
 631         "       .section        .fixup,\"ax\"                   \n"     \
 632         "4:     li      %0, %4                                  \n"     \
 633         "       j       3b                                      \n"     \
 634         "       .previous                                       \n"     \
 635         "       .section        __ex_table,\"a\"                \n"     \
 636         "       " __UA_ADDR "   1b, 4b                          \n"     \
 637         "       " __UA_ADDR "   1b + 4, 4b                      \n"     \
 638         "       " __UA_ADDR "   2b, 4b                          \n"     \
 639         "       " __UA_ADDR "   2b + 4, 4b                      \n"     \
 640         "       .previous"                                              \
 641         : "=r" (__pu_err)                                               \
 642         : "0" (0), "r" (__pu_val), "r" (ptr),                           \
 643           "i" (-EFAULT));                                               \
 644 }
 645
 646 extern void __put_user_unaligned_unknown(void);
 647
 648 /*
 649  * We're generating jump to subroutines which will be outside the range of
 650  * jump instructions
 651  */
 652 #ifdef MODULE
 653 #define __MODULE_JAL(destination)                                       \
 654         ".set\tnoat\n\t"                                                \
 655         __UA_LA "\t$1, " #destination "\n\t"                            \
 656         "jalr\t$1\n\t"                                                  \
 657         ".set\tat\n\t"
 658 #else
 659 #define __MODULE_JAL(destination)                                       \
 660         "jal\t" #destination "\n\t"
 661 #endif
 662
 663 #ifndef CONFIG_CPU_DADDI_WORKAROUNDS
 664 #define DADDI_SCRATCH "$0"
 665 #else
 666 #define DADDI_SCRATCH "$3"
 667 #endif
 668
 669 extern size_t __copy_user(void *__to, const void *__from, size_t __n);
 670
 671 #define __invoke_copy_to_user(to, from, n)                              \
 672 ({                                                                      \
 673         register void __user *__cu_to_r __asm__("$4");                  \
 674         register const void *__cu_from_r __asm__("$5");                 \
 675         register long __cu_len_r __asm__("$6");                         \
 676                                                                         \
 677         __cu_to_r = (to);                                               \
 678         __cu_from_r = (from);                                           \
 679         __cu_len_r = (n);                                               \
 680         __asm__ __volatile__(                                           \
 681         __MODULE_JAL(__copy_user)                                       \
 682         : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)       \
 683         :                                                               \
 684         : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",         \
 685           DADDI_SCRATCH, "memory");                                     \
 686         __cu_len_r;                                                     \
 687 })
 688
 689 /*
 690  * __copy_to_user: - Copy a block of data into user space, with less checking.
 691  * @to:   Destination address, in user space.
 692  * @from: Source address, in kernel space.
 693  * @n:    Number of bytes to copy.
 694  *
 695  * Context: User context only.  This function may sleep.
 696  *
 697  * Copy data from kernel space to user space.  Caller must check
 698  * the specified block with access_ok() before calling this function.
 699  *
 700  * Returns number of bytes that could not be copied.
 701  * On success, this will be zero.
 702  */
 703 #define __copy_to_user(to, from, n)                                     \
 704 ({                                                                      \
 705         void __user *__cu_to;                                           \
 706         const void *__cu_from;                                          \
 707         long __cu_len;                                                  \
 708                                                                         \
 709         might_sleep();                                                  \
 710         __cu_to = (to);                                                 \
 711         __cu_from = (from);                                             \
 712         __cu_len = (n);                                                 \
 713         __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
 714         __cu_len;                                                       \
 715 })
 716
 717 extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
 718
 719 #define __copy_to_user_inatomic(to, from, n)                            \
 720 ({                                                                      \
 721         void __user *__cu_to;                                           \
 722         const void *__cu_from;                                          \
 723         long __cu_len;                                                  \
 724                                                                         \
 725         __cu_to = (to);                                                 \
 726         __cu_from = (from);                                             \
 727         __cu_len = (n);                                                 \
 728         __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
 729         __cu_len;                                                       \
 730 })
 731
 732 #define __copy_from_user_inatomic(to, from, n)                          \
 733 ({                                                                      \
 734         void *__cu_to;                                                  \
 735         const void __user *__cu_from;                                   \
 736         long __cu_len;                                                  \
 737                                                                         \
 738         __cu_to = (to);                                                 \
 739         __cu_from = (from);                                             \
 740         __cu_len = (n);                                                 \
 741         __cu_len = __invoke_copy_from_user_inatomic(__cu_to, __cu_from, \
 742                                                     __cu_len);          \
 743         __cu_len;                                                       \
 744 })
 745
 746 /*
 747  * copy_to_user: - Copy a block of data into user space.
 748  * @to:   Destination address, in user space.
 749  * @from: Source address, in kernel space.
 750  * @n:    Number of bytes to copy.
 751  *
 752  * Context: User context only.  This function may sleep.
 753  *
 754  * Copy data from kernel space to user space.
 755  *
 756  * Returns number of bytes that could not be copied.
 757  * On success, this will be zero.
 758  */
 759 #define copy_to_user(to, from, n)                                       \
 760 ({                                                                      \
 761         void __user *__cu_to;                                           \
 762         const void *__cu_from;                                          \
 763         long __cu_len;                                                  \
 764                                                                         \
 765         might_sleep();                                                  \
 766         __cu_to = (to);                                                 \
 767         __cu_from = (from);                                             \
 768         __cu_len = (n);                                                 \
 769         if (access_ok(VERIFY_WRITE, __cu_to, __cu_len))                 \
 770                 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from,    \
 771                                                  __cu_len);             \
 772         __cu_len;                                                       \
 773 })
 774
 775 #define __invoke_copy_from_user(to, from, n)                            \
 776 ({                                                                      \
 777         register void *__cu_to_r __asm__("$4");                         \
 778         register const void __user *__cu_from_r __asm__("$5");          \
 779         register long __cu_len_r __asm__("$6");                         \
 780                                                                         \
 781         __cu_to_r = (to);                                               \
 782         __cu_from_r = (from);                                           \
 783         __cu_len_r = (n);                                               \
 784         __asm__ __volatile__(                                           \
 785         ".set\tnoreorder\n\t"                                           \
 786         __MODULE_JAL(__copy_user)                                       \
 787         ".set\tnoat\n\t"                                                \
 788         __UA_ADDU "\t$1, %1, %2\n\t"                                    \
 789         ".set\tat\n\t"                                                  \
 790         ".set\treorder"                                                 \
 791         : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)       \
 792         :                                                               \
 793         : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",         \
 794           DADDI_SCRATCH, "memory");                                     \
 795         __cu_len_r;                                                     \
 796 })
 797
 798 #define __invoke_copy_from_user_inatomic(to, from, n)                   \
 799 ({                                                                      \
 800         register void *__cu_to_r __asm__("$4");                         \
 801         register const void __user *__cu_from_r __asm__("$5");          \
 802         register long __cu_len_r __asm__("$6");                         \
 803                                                                         \
 804         __cu_to_r = (to);                                               \
 805         __cu_from_r = (from);                                           \
 806         __cu_len_r = (n);                                               \
 807         __asm__ __volatile__(                                           \
 808         ".set\tnoreorder\n\t"                                           \
 809         __MODULE_JAL(__copy_user_inatomic)                              \
 810         ".set\tnoat\n\t"                                                \
 811         __UA_ADDU "\t$1, %1, %2\n\t"                                    \
 812         ".set\tat\n\t"                                                  \
 813         ".set\treorder"                                                 \
 814         : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)       \
 815         :                                                               \
 816         : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",         \
 817           DADDI_SCRATCH, "memory");                                     \
 818         __cu_len_r;                                                     \
 819 })
 820
 821 /*
 822  * __copy_from_user: - Copy a block of data from user space, with less checking.
 823  * @to:   Destination address, in kernel space.
 824  * @from: Source address, in user space.
 825  * @n:    Number of bytes to copy.
 826  *
 827  * Context: User context only.  This function may sleep.
 828  *
 829  * Copy data from user space to kernel space.  Caller must check
 830  * the specified block with access_ok() before calling this function.
 831  *
 832  * Returns number of bytes that could not be copied.
 833  * On success, this will be zero.
 834  *
 835  * If some data could not be copied, this function will pad the copied
 836  * data to the requested size using zero bytes.
 837  */
 838 #define __copy_from_user(to, from, n)                                   \
 839 ({                                                                      \
 840         void *__cu_to;                                                  \
 841         const void __user *__cu_from;                                   \
 842         long __cu_len;                                                  \
 843                                                                         \
 844         might_sleep();                                                  \
 845         __cu_to = (to);                                                 \
 846         __cu_from = (from);                                             \
 847         __cu_len = (n);                                                 \
 848         __cu_len = __invoke_copy_from_user(__cu_to, __cu_from,          \
 849                                            __cu_len);                   \
 850         __cu_len;                                                       \
 851 })
 852
 853 /*
 854  * copy_from_user: - Copy a block of data from user space.
 855  * @to:   Destination address, in kernel space.
 856  * @from: Source address, in user space.
 857  * @n:    Number of bytes to copy.
 858  *
 859  * Context: User context only.  This function may sleep.
 860  *
 861  * Copy data from user space to kernel space.
 862  *
 863  * Returns number of bytes that could not be copied.
 864  * On success, this will be zero.
 865  *
 866  * If some data could not be copied, this function will pad the copied
 867  * data to the requested size using zero bytes.
 868  */
 869 #define copy_from_user(to, from, n)                                     \
 870 ({                                                                      \
 871         void *__cu_to;                                                  \
 872         const void __user *__cu_from;                                   \
 873         long __cu_len;                                                  \
 874                                                                         \
 875         might_sleep();                                                  \
 876         __cu_to = (to);                                                 \
 877         __cu_from = (from);                                             \
 878         __cu_len = (n);                                                 \
 879         if (access_ok(VERIFY_READ, __cu_from, __cu_len))                \
 880                 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from,  \
 881                                                    __cu_len);           \
 882         __cu_len;                                                       \
 883 })
 884
 885 #define __copy_in_user(to, from, n)     __copy_from_user(to, from, n)
 886
 887 #define copy_in_user(to, from, n)                                       \
 888 ({                                                                      \
 889         void __user *__cu_to;                                           \
 890         const void __user *__cu_from;                                   \
 891         long __cu_len;                                                  \
 892                                                                         \
 893         might_sleep();                                                  \
 894         __cu_to = (to);                                                 \
 895         __cu_from = (from);                                             \
 896         __cu_len = (n);                                                 \
 897         if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&       \
 898                    access_ok(VERIFY_WRITE, __cu_to, __cu_len)))         \
 899                 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from,  \
 900                                                    __cu_len);           \
 901         __cu_len;                                                       \
 902 })
 903
 904 /*
 905  * __clear_user: - Zero a block of memory in user space, with less checking.
 906  * @to:   Destination address, in user space.
 907  * @n:    Number of bytes to zero.
 908  *
 909  * Zero a block of memory in user space.  Caller must check
 910  * the specified block with access_ok() before calling this function.
 911  *
 912  * Returns number of bytes that could not be cleared.
 913  * On success, this will be zero.
 914  */
 915 static inline __kernel_size_t
 916 __clear_user(void __user *addr, __kernel_size_t size)
 917 {
 918         __kernel_size_t res;
 919
 920         might_sleep();
 921         __asm__ __volatile__(
 922                 "move\t$4, %1\n\t"
 923                 "move\t$5, $0\n\t"
 924                 "move\t$6, %2\n\t"
 925                 __MODULE_JAL(__bzero)
 926                 "move\t%0, $6"
 927                 : "=r" (res)
 928                 : "r" (addr), "r" (size)
 929                 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
 930
 931         return res;
 932 }
 933
 934 #define clear_user(addr,n)                                              \
 935 ({                                                                      \
 936         void __user * __cl_addr = (addr);                               \
 937         unsigned long __cl_size = (n);                                  \
 938         if (__cl_size && access_ok(VERIFY_WRITE,                        \
 939                 ((unsigned long)(__cl_addr)), __cl_size))               \
 940                 __cl_size = __clear_user(__cl_addr, __cl_size);         \
 941         __cl_size;                                                      \
 942 })
 943
 944 /*
 945  * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
 946  * @dst:   Destination address, in kernel space.  This buffer must be at
 947  *         least @count bytes long.
 948  * @src:   Source address, in user space.
 949  * @count: Maximum number of bytes to copy, including the trailing NUL.
 950  *
 951  * Copies a NUL-terminated string from userspace to kernel space.
 952  * Caller must check the specified block with access_ok() before calling
 953  * this function.
 954  *
 955  * On success, returns the length of the string (not including the trailing
 956  * NUL).
 957  *
 958  * If access to userspace fails, returns -EFAULT (some data may have been
 959  * copied).
 960  *
 961  * If @count is smaller than the length of the string, copies @count bytes
 962  * and returns @count.
 963  */
 964 static inline long
 965 __strncpy_from_user(char *__to, const char __user *__from, long __len)
 966 {
 967         long res;
 968
 969         might_sleep();
 970         __asm__ __volatile__(
 971                 "move\t$4, %1\n\t"
 972                 "move\t$5, %2\n\t"
 973                 "move\t$6, %3\n\t"
 974                 __MODULE_JAL(__strncpy_from_user_nocheck_asm)
 975                 "move\t%0, $2"
 976                 : "=r" (res)
 977                 : "r" (__to), "r" (__from), "r" (__len)
 978                 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
 979
 980         return res;
 981 }
 982
 983 /*
 984  * strncpy_from_user: - Copy a NUL terminated string from userspace.
 985  * @dst:   Destination address, in kernel space.  This buffer must be at
 986  *         least @count bytes long.
 987  * @src:   Source address, in user space.
 988  * @count: Maximum number of bytes to copy, including the trailing NUL.
 989  *
 990  * Copies a NUL-terminated string from userspace to kernel space.
 991  *
 992  * On success, returns the length of the string (not including the trailing
 993  * NUL).
 994  *
 995  * If access to userspace fails, returns -EFAULT (some data may have been
 996  * copied).
 997  *
 998  * If @count is smaller than the length of the string, copies @count bytes
 999  * and returns @count.
1000  */
1001 static inline long
1002 strncpy_from_user(char *__to, const char __user *__from, long __len)
1003 {
1004         long res;
1005
1006         might_sleep();
1007         __asm__ __volatile__(
1008                 "move\t$4, %1\n\t"
1009                 "move\t$5, %2\n\t"
1010                 "move\t$6, %3\n\t"
1011                 __MODULE_JAL(__strncpy_from_user_asm)
1012                 "move\t%0, $2"
1013                 : "=r" (res)
1014                 : "r" (__to), "r" (__from), "r" (__len)
1015                 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1016
1017         return res;
1018 }
1019
1020 /* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1021 static inline long __strlen_user(const char __user *s)
1022 {
1023         long res;
1024
1025         might_sleep();
1026         __asm__ __volatile__(
1027                 "move\t$4, %1\n\t"
1028                 __MODULE_JAL(__strlen_user_nocheck_asm)
1029                 "move\t%0, $2"
1030                 : "=r" (res)
1031                 : "r" (s)
1032                 : "$2", "$4", __UA_t0, "$31");
1033
1034         return res;
1035 }
1036
1037 /*
1038  * strlen_user: - Get the size of a string in user space.
1039  * @str: The string to measure.
1040  *
1041  * Context: User context only.  This function may sleep.
1042  *
1043  * Get the size of a NUL-terminated string in user space.
1044  *
1045  * Returns the size of the string INCLUDING the terminating NUL.
1046  * On exception, returns 0.
1047  *
1048  * If there is a limit on the length of a valid string, you may wish to
1049  * consider using strnlen_user() instead.
1050  */
1051 static inline long strlen_user(const char __user *s)
1052 {
1053         long res;
1054
1055         might_sleep();
1056         __asm__ __volatile__(
1057                 "move\t$4, %1\n\t"
1058                 __MODULE_JAL(__strlen_user_asm)
1059                 "move\t%0, $2"
1060                 : "=r" (res)
1061                 : "r" (s)
1062                 : "$2", "$4", __UA_t0, "$31");
1063
1064         return res;
1065 }
1066
1067 /* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1068 static inline long __strnlen_user(const char __user *s, long n)
1069 {
1070         long res;
1071
1072         might_sleep();
1073         __asm__ __volatile__(
1074                 "move\t$4, %1\n\t"
1075                 "move\t$5, %2\n\t"
1076                 __MODULE_JAL(__strnlen_user_nocheck_asm)
1077                 "move\t%0, $2"
1078                 : "=r" (res)
1079                 : "r" (s), "r" (n)
1080                 : "$2", "$4", "$5", __UA_t0, "$31");
1081
1082         return res;
1083 }
1084
1085 /*
1086  * strlen_user: - Get the size of a string in user space.
1087  * @str: The string to measure.
1088  *
1089  * Context: User context only.  This function may sleep.
1090  *
1091  * Get the size of a NUL-terminated string in user space.
1092  *
1093  * Returns the size of the string INCLUDING the terminating NUL.
1094  * On exception, returns 0.
1095  *
1096  * If there is a limit on the length of a valid string, you may wish to
1097  * consider using strnlen_user() instead.
1098  */
1099 static inline long strnlen_user(const char __user *s, long n)
1100 {
1101         long res;
1102
1103         might_sleep();
1104         __asm__ __volatile__(
1105                 "move\t$4, %1\n\t"
1106                 "move\t$5, %2\n\t"
1107                 __MODULE_JAL(__strnlen_user_asm)
1108                 "move\t%0, $2"
1109                 : "=r" (res)
1110                 : "r" (s), "r" (n)
1111                 : "$2", "$4", "$5", __UA_t0, "$31");
1112
1113         return res;
1114 }
1115
1116 struct exception_table_entry
1117 {
1118         unsigned long insn;
1119         unsigned long nextinsn;
1120 };
1121
1122 extern int fixup_exception(struct pt_regs *regs);
1123
1124 #endif /* _ASM_UACCESS_H */