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         unsigned long __addr = (unsigned long) (addr);                  \
 110         unsigned long __size = size;                                    \
 111         unsigned long __mask = mask;                                    \
 112         unsigned long __ok;                                             \
 113                                                                         \
 114         __chk_user_ptr(addr);                                           \
 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         __chk_user_ptr(ptr);                                            \
 239         __get_user_common((x), size, ptr);                              \
 240         __gu_err;                                                       \
 241 })
 242
 243 #define __get_user_check(x, ptr, size)                                  \
 244 ({                                                                      \
 245         int __gu_err = -EFAULT;                                         \
 246         const __typeof__(*(ptr)) __user * __gu_ptr = (ptr);             \
 247                                                                         \
 248         if (likely(access_ok(VERIFY_READ,  __gu_ptr, size)))            \
 249                 __get_user_common((x), size, __gu_ptr);                 \
 250                                                                         \
 251         __gu_err;                                                       \
 252 })
 253
 254 #define __get_user_asm(val, insn, addr)                                 \
 255 {                                                                       \
 256         long __gu_tmp;                                                  \
 257                                                                         \
 258         __asm__ __volatile__(                                           \
 259         "1:     " insn "        %1, %3                          \n"     \
 260         "2:                                                     \n"     \
 261         "       .section .fixup,\"ax\"                          \n"     \
 262         "3:     li      %0, %4                                  \n"     \
 263         "       j       2b                                      \n"     \
 264         "       .previous                                       \n"     \
 265         "       .section __ex_table,\"a\"                       \n"     \
 266         "       "__UA_ADDR "\t1b, 3b                            \n"     \
 267         "       .previous                                       \n"     \
 268         : "=r" (__gu_err), "=r" (__gu_tmp)                              \
 269         : "0" (0), "o" (__m(addr)), "i" (-EFAULT));                     \
 270                                                                         \
 271         (val) = (__typeof__(*(addr))) __gu_tmp;                         \
 272 }
 273
 274 /*
 275  * Get a long long 64 using 32 bit registers.
 276  */
 277 #define __get_user_asm_ll32(val, addr)                                  \
 278 {                                                                       \
 279         union {                                                         \
 280                 unsigned long long      l;                              \
 281                 __typeof__(*(addr))     t;                              \
 282         } __gu_tmp;                                                     \
 283                                                                         \
 284         __asm__ __volatile__(                                           \
 285         "1:     lw      %1, (%3)                                \n"     \
 286         "2:     lw      %D1, 4(%3)                              \n"     \
 287         "3:     .section        .fixup,\"ax\"                   \n"     \
 288         "4:     li      %0, %4                                  \n"     \
 289         "       move    %1, $0                                  \n"     \
 290         "       move    %D1, $0                                 \n"     \
 291         "       j       3b                                      \n"     \
 292         "       .previous                                       \n"     \
 293         "       .section        __ex_table,\"a\"                \n"     \
 294         "       " __UA_ADDR "   1b, 4b                          \n"     \
 295         "       " __UA_ADDR "   2b, 4b                          \n"     \
 296         "       .previous                                       \n"     \
 297         : "=r" (__gu_err), "=&r" (__gu_tmp.l)                           \
 298         : "0" (0), "r" (addr), "i" (-EFAULT));                          \
 299                                                                         \
 300         (val) = __gu_tmp.t;                                             \
 301 }
 302
 303 /*
 304  * Yuck.  We need two variants, one for 64bit operation and one
 305  * for 32 bit mode and old iron.
 306  */
 307 #ifdef CONFIG_32BIT
 308 #define __PUT_USER_DW(ptr) __put_user_asm_ll32(ptr)
 309 #endif
 310 #ifdef CONFIG_64BIT
 311 #define __PUT_USER_DW(ptr) __put_user_asm("sd", ptr)
 312 #endif
 313
 314 #define __put_user_nocheck(x, ptr, size)                                \
 315 ({                                                                      \
 316         __typeof__(*(ptr)) __pu_val;                                    \
 317         int __pu_err = 0;                                               \
 318                                                                         \
 319         __chk_user_ptr(ptr);                                            \
 320         __pu_val = (x);                                                 \
 321         switch (size) {                                                 \
 322         case 1: __put_user_asm("sb", ptr); break;                       \
 323         case 2: __put_user_asm("sh", ptr); break;                       \
 324         case 4: __put_user_asm("sw", ptr); break;                       \
 325         case 8: __PUT_USER_DW(ptr); break;                              \
 326         default: __put_user_unknown(); break;                           \
 327         }                                                               \
 328         __pu_err;                                                       \
 329 })
 330
 331 #define __put_user_check(x, ptr, size)                                  \
 332 ({                                                                      \
 333         __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
 334         __typeof__(*(ptr)) __pu_val = (x);                              \
 335         int __pu_err = -EFAULT;                                         \
 336                                                                         \
 337         if (likely(access_ok(VERIFY_WRITE,  __pu_addr, size))) {        \
 338                 switch (size) {                                         \
 339                 case 1: __put_user_asm("sb", __pu_addr); break;         \
 340                 case 2: __put_user_asm("sh", __pu_addr); break;         \
 341                 case 4: __put_user_asm("sw", __pu_addr); break;         \
 342                 case 8: __PUT_USER_DW(__pu_addr); break;                \
 343                 default: __put_user_unknown(); break;                   \
 344                 }                                                       \
 345         }                                                               \
 346         __pu_err;                                                       \
 347 })
 348
 349 #define __put_user_asm(insn, ptr)                                       \
 350 {                                                                       \
 351         __asm__ __volatile__(                                           \
 352         "1:     " insn "        %z2, %3         # __put_user_asm\n"     \
 353         "2:                                                     \n"     \
 354         "       .section        .fixup,\"ax\"                   \n"     \
 355         "3:     li      %0, %4                                  \n"     \
 356         "       j       2b                                      \n"     \
 357         "       .previous                                       \n"     \
 358         "       .section        __ex_table,\"a\"                \n"     \
 359         "       " __UA_ADDR "   1b, 3b                          \n"     \
 360         "       .previous                                       \n"     \
 361         : "=r" (__pu_err)                                               \
 362         : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)),                     \
 363           "i" (-EFAULT));                                               \
 364 }
 365
 366 #define __put_user_asm_ll32(ptr)                                        \
 367 {                                                                       \
 368         __asm__ __volatile__(                                           \
 369         "1:     sw      %2, (%3)        # __put_user_asm_ll32   \n"     \
 370         "2:     sw      %D2, 4(%3)                              \n"     \
 371         "3:                                                     \n"     \
 372         "       .section        .fixup,\"ax\"                   \n"     \
 373         "4:     li      %0, %4                                  \n"     \
 374         "       j       3b                                      \n"     \
 375         "       .previous                                       \n"     \
 376         "       .section        __ex_table,\"a\"                \n"     \
 377         "       " __UA_ADDR "   1b, 4b                          \n"     \
 378         "       " __UA_ADDR "   2b, 4b                          \n"     \
 379         "       .previous"                                              \
 380         : "=r" (__pu_err)                                               \
 381         : "0" (0), "r" (__pu_val), "r" (ptr),                           \
 382           "i" (-EFAULT));                                               \
 383 }
 384
 385 extern void __put_user_unknown(void);
 386
 387 /*
 388  * put_user_unaligned: - Write a simple value into user space.
 389  * @x:   Value to copy to user space.
 390  * @ptr: Destination address, in user space.
 391  *
 392  * Context: User context only.  This function may sleep.
 393  *
 394  * This macro copies a single simple value from kernel space to user
 395  * space.  It supports simple types like char and int, but not larger
 396  * data types like structures or arrays.
 397  *
 398  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 399  * to the result of dereferencing @ptr.
 400  *
 401  * Returns zero on success, or -EFAULT on error.
 402  */
 403 #define put_user_unaligned(x,ptr)       \
 404         __put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
 405
 406 /*
 407  * get_user_unaligned: - Get a simple variable from user space.
 408  * @x:   Variable to store result.
 409  * @ptr: Source address, in user space.
 410  *
 411  * Context: User context only.  This function may sleep.
 412  *
 413  * This macro copies a single simple variable from user space to kernel
 414  * space.  It supports simple types like char and int, but not larger
 415  * data types like structures or arrays.
 416  *
 417  * @ptr must have pointer-to-simple-variable type, and the result of
 418  * dereferencing @ptr must be assignable to @x without a cast.
 419  *
 420  * Returns zero on success, or -EFAULT on error.
 421  * On error, the variable @x is set to zero.
 422  */
 423 #define get_user_unaligned(x,ptr) \
 424         __get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
 425
 426 /*
 427  * __put_user_unaligned: - Write a simple value into user space, with less checking.
 428  * @x:   Value to copy to user space.
 429  * @ptr: Destination address, in user space.
 430  *
 431  * Context: User context only.  This function may sleep.
 432  *
 433  * This macro copies a single simple value from kernel space to user
 434  * space.  It supports simple types like char and int, but not larger
 435  * data types like structures or arrays.
 436  *
 437  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 438  * to the result of dereferencing @ptr.
 439  *
 440  * Caller must check the pointer with access_ok() before calling this
 441  * function.
 442  *
 443  * Returns zero on success, or -EFAULT on error.
 444  */
 445 #define __put_user_unaligned(x,ptr) \
 446         __put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
 447
 448 /*
 449  * __get_user_unaligned: - Get a simple variable from user space, with less checking.
 450  * @x:   Variable to store result.
 451  * @ptr: Source address, in user space.
 452  *
 453  * Context: User context only.  This function may sleep.
 454  *
 455  * This macro copies a single simple variable from user space to kernel
 456  * space.  It supports simple types like char and int, but not larger
 457  * data types like structures or arrays.
 458  *
 459  * @ptr must have pointer-to-simple-variable type, and the result of
 460  * dereferencing @ptr must be assignable to @x without a cast.
 461  *
 462  * Caller must check the pointer with access_ok() before calling this
 463  * function.
 464  *
 465  * Returns zero on success, or -EFAULT on error.
 466  * On error, the variable @x is set to zero.
 467  */
 468 #define __get_user_unaligned(x,ptr) \
 469         __get_user__unalignednocheck((x),(ptr),sizeof(*(ptr)))
 470
 471 /*
 472  * Yuck.  We need two variants, one for 64bit operation and one
 473  * for 32 bit mode and old iron.
 474  */
 475 #ifdef CONFIG_32BIT
 476 #define __GET_USER_UNALIGNED_DW(val, ptr)                               \
 477         __get_user_unaligned_asm_ll32(val, ptr)
 478 #endif
 479 #ifdef CONFIG_64BIT
 480 #define __GET_USER_UNALIGNED_DW(val, ptr)                               \
 481         __get_user_unaligned_asm(val, "uld", ptr)
 482 #endif
 483
 484 extern void __get_user_unaligned_unknown(void);
 485
 486 #define __get_user_unaligned_common(val, size, ptr)                     \
 487 do {                                                                    \
 488         switch (size) {                                                 \
 489         case 1: __get_user_asm(val, "lb", ptr); break;                  \
 490         case 2: __get_user_unaligned_asm(val, "ulh", ptr); break;       \
 491         case 4: __get_user_unaligned_asm(val, "ulw", ptr); break;       \
 492         case 8: __GET_USER_UNALIGNED_DW(val, ptr); break;               \
 493         default: __get_user_unaligned_unknown(); break;                 \
 494         }                                                               \
 495 } while (0)
 496
 497 #define __get_user_unaligned_nocheck(x,ptr,size)                        \
 498 ({                                                                      \
 499         int __gu_err;                                                   \
 500                                                                         \
 501         __get_user_unaligned_common((x), size, ptr);                    \
 502         __gu_err;                                                       \
 503 })
 504
 505 #define __get_user_unaligned_check(x,ptr,size)                          \
 506 ({                                                                      \
 507         int __gu_err = -EFAULT;                                         \
 508         const __typeof__(*(ptr)) __user * __gu_ptr = (ptr);             \
 509                                                                         \
 510         if (likely(access_ok(VERIFY_READ,  __gu_ptr, size)))            \
 511                 __get_user_unaligned_common((x), size, __gu_ptr);       \
 512                                                                         \
 513         __gu_err;                                                       \
 514 })
 515
 516 #define __get_user_unaligned_asm(val, insn, addr)                       \
 517 {                                                                       \
 518         long __gu_tmp;                                                  \
 519                                                                         \
 520         __asm__ __volatile__(                                           \
 521         "1:     " insn "        %1, %3                          \n"     \
 522         "2:                                                     \n"     \
 523         "       .section .fixup,\"ax\"                          \n"     \
 524         "3:     li      %0, %4                                  \n"     \
 525         "       j       2b                                      \n"     \
 526         "       .previous                                       \n"     \
 527         "       .section __ex_table,\"a\"                       \n"     \
 528         "       "__UA_ADDR "\t1b, 3b                            \n"     \
 529         "       "__UA_ADDR "\t1b + 4, 3b                        \n"     \
 530         "       .previous                                       \n"     \
 531         : "=r" (__gu_err), "=r" (__gu_tmp)                              \
 532         : "0" (0), "o" (__m(addr)), "i" (-EFAULT));                     \
 533                                                                         \
 534         (val) = (__typeof__(*(addr))) __gu_tmp;                         \
 535 }
 536
 537 /*
 538  * Get a long long 64 using 32 bit registers.
 539  */
 540 #define __get_user_unaligned_asm_ll32(val, addr)                        \
 541 {                                                                       \
 542         unsigned long long __gu_tmp;                                    \
 543                                                                         \
 544         __asm__ __volatile__(                                           \
 545         "1:     ulw     %1, (%3)                                \n"     \
 546         "2:     ulw     %D1, 4(%3)                              \n"     \
 547         "       move    %0, $0                                  \n"     \
 548         "3:     .section        .fixup,\"ax\"                   \n"     \
 549         "4:     li      %0, %4                                  \n"     \
 550         "       move    %1, $0                                  \n"     \
 551         "       move    %D1, $0                                 \n"     \
 552         "       j       3b                                      \n"     \
 553         "       .previous                                       \n"     \
 554         "       .section        __ex_table,\"a\"                \n"     \
 555         "       " __UA_ADDR "   1b, 4b                          \n"     \
 556         "       " __UA_ADDR "   1b + 4, 4b                      \n"     \
 557         "       " __UA_ADDR "   2b, 4b                          \n"     \
 558         "       " __UA_ADDR "   2b + 4, 4b                      \n"     \
 559         "       .previous                                       \n"     \
 560         : "=r" (__gu_err), "=&r" (__gu_tmp)                             \
 561         : "0" (0), "r" (addr), "i" (-EFAULT));                          \
 562         (val) = (__typeof__(*(addr))) __gu_tmp;                         \
 563 }
 564
 565 /*
 566  * Yuck.  We need two variants, one for 64bit operation and one
 567  * for 32 bit mode and old iron.
 568  */
 569 #ifdef CONFIG_32BIT
 570 #define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
 571 #endif
 572 #ifdef CONFIG_64BIT
 573 #define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
 574 #endif
 575
 576 #define __put_user_unaligned_nocheck(x,ptr,size)                        \
 577 ({                                                                      \
 578         __typeof__(*(ptr)) __pu_val;                                    \
 579         int __pu_err = 0;                                               \
 580                                                                         \
 581         __pu_val = (x);                                                 \
 582         switch (size) {                                                 \
 583         case 1: __put_user_asm("sb", ptr); break;                       \
 584         case 2: __put_user_unaligned_asm("ush", ptr); break;            \
 585         case 4: __put_user_unaligned_asm("usw", ptr); break;            \
 586         case 8: __PUT_USER_UNALIGNED_DW(ptr); break;                    \
 587         default: __put_user_unaligned_unknown(); break;                 \
 588         }                                                               \
 589         __pu_err;                                                       \
 590 })
 591
 592 #define __put_user_unaligned_check(x,ptr,size)                          \
 593 ({                                                                      \
 594         __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
 595         __typeof__(*(ptr)) __pu_val = (x);                              \
 596         int __pu_err = -EFAULT;                                         \
 597                                                                         \
 598         if (likely(access_ok(VERIFY_WRITE,  __pu_addr, size))) {        \
 599                 switch (size) {                                         \
 600                 case 1: __put_user_asm("sb", __pu_addr); break;         \
 601                 case 2: __put_user_unaligned_asm("ush", __pu_addr); break; \
 602                 case 4: __put_user_unaligned_asm("usw", __pu_addr); break; \
 603                 case 8: __PUT_USER_UNALGINED_DW(__pu_addr); break;      \
 604                 default: __put_user_unaligned_unknown(); break;         \
 605                 }                                                       \
 606         }                                                               \
 607         __pu_err;                                                       \
 608 })
 609
 610 #define __put_user_unaligned_asm(insn, ptr)                             \
 611 {                                                                       \
 612         __asm__ __volatile__(                                           \
 613         "1:     " insn "        %z2, %3         # __put_user_unaligned_asm\n" \
 614         "2:                                                     \n"     \
 615         "       .section        .fixup,\"ax\"                   \n"     \
 616         "3:     li      %0, %4                                  \n"     \
 617         "       j       2b                                      \n"     \
 618         "       .previous                                       \n"     \
 619         "       .section        __ex_table,\"a\"                \n"     \
 620         "       " __UA_ADDR "   1b, 3b                          \n"     \
 621         "       .previous                                       \n"     \
 622         : "=r" (__pu_err)                                               \
 623         : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)),                     \
 624           "i" (-EFAULT));                                               \
 625 }
 626
 627 #define __put_user_unaligned_asm_ll32(ptr)                              \
 628 {                                                                       \
 629         __asm__ __volatile__(                                           \
 630         "1:     sw      %2, (%3)        # __put_user_unaligned_asm_ll32 \n" \
 631         "2:     sw      %D2, 4(%3)                              \n"     \
 632         "3:                                                     \n"     \
 633         "       .section        .fixup,\"ax\"                   \n"     \
 634         "4:     li      %0, %4                                  \n"     \
 635         "       j       3b                                      \n"     \
 636         "       .previous                                       \n"     \
 637         "       .section        __ex_table,\"a\"                \n"     \
 638         "       " __UA_ADDR "   1b, 4b                          \n"     \
 639         "       " __UA_ADDR "   1b + 4, 4b                      \n"     \
 640         "       " __UA_ADDR "   2b, 4b                          \n"     \
 641         "       " __UA_ADDR "   2b + 4, 4b                      \n"     \
 642         "       .previous"                                              \
 643         : "=r" (__pu_err)                                               \
 644         : "0" (0), "r" (__pu_val), "r" (ptr),                           \
 645           "i" (-EFAULT));                                               \
 646 }
 647
 648 extern void __put_user_unaligned_unknown(void);
 649
 650 /*
 651  * We're generating jump to subroutines which will be outside the range of
 652  * jump instructions
 653  */
 654 #ifdef MODULE
 655 #define __MODULE_JAL(destination)                                       \
 656         ".set\tnoat\n\t"                                                \
 657         __UA_LA "\t$1, " #destination "\n\t"                            \
 658         "jalr\t$1\n\t"                                                  \
 659         ".set\tat\n\t"
 660 #else
 661 #define __MODULE_JAL(destination)                                       \
 662         "jal\t" #destination "\n\t"
 663 #endif
 664
 665 #ifndef CONFIG_CPU_DADDI_WORKAROUNDS
 666 #define DADDI_SCRATCH "$0"
 667 #else
 668 #define DADDI_SCRATCH "$3"
 669 #endif
 670
 671 extern size_t __copy_user(void *__to, const void *__from, size_t __n);
 672
 673 #define __invoke_copy_to_user(to, from, n)                              \
 674 ({                                                                      \
 675         register void __user *__cu_to_r __asm__("$4");                  \
 676         register const void *__cu_from_r __asm__("$5");                 \
 677         register long __cu_len_r __asm__("$6");                         \
 678                                                                         \
 679         __cu_to_r = (to);                                               \
 680         __cu_from_r = (from);                                           \
 681         __cu_len_r = (n);                                               \
 682         __asm__ __volatile__(                                           \
 683         __MODULE_JAL(__copy_user)                                       \
 684         : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)       \
 685         :                                                               \
 686         : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",         \
 687           DADDI_SCRATCH, "memory");                                     \
 688         __cu_len_r;                                                     \
 689 })
 690
 691 /*
 692  * __copy_to_user: - Copy a block of data into user space, with less checking.
 693  * @to:   Destination address, in user space.
 694  * @from: Source address, in kernel space.
 695  * @n:    Number of bytes to copy.
 696  *
 697  * Context: User context only.  This function may sleep.
 698  *
 699  * Copy data from kernel space to user space.  Caller must check
 700  * the specified block with access_ok() before calling this function.
 701  *
 702  * Returns number of bytes that could not be copied.
 703  * On success, this will be zero.
 704  */
 705 #define __copy_to_user(to, from, n)                                     \
 706 ({                                                                      \
 707         void __user *__cu_to;                                           \
 708         const void *__cu_from;                                          \
 709         long __cu_len;                                                  \
 710                                                                         \
 711         might_sleep();                                                  \
 712         __cu_to = (to);                                                 \
 713         __cu_from = (from);                                             \
 714         __cu_len = (n);                                                 \
 715         __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
 716         __cu_len;                                                       \
 717 })
 718
 719 extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
 720
 721 #define __copy_to_user_inatomic(to, from, n)                            \
 722 ({                                                                      \
 723         void __user *__cu_to;                                           \
 724         const void *__cu_from;                                          \
 725         long __cu_len;                                                  \
 726                                                                         \
 727         __cu_to = (to);                                                 \
 728         __cu_from = (from);                                             \
 729         __cu_len = (n);                                                 \
 730         __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
 731         __cu_len;                                                       \
 732 })
 733
 734 #define __copy_from_user_inatomic(to, from, n)                          \
 735 ({                                                                      \
 736         void *__cu_to;                                                  \
 737         const void __user *__cu_from;                                   \
 738         long __cu_len;                                                  \
 739                                                                         \
 740         __cu_to = (to);                                                 \
 741         __cu_from = (from);                                             \
 742         __cu_len = (n);                                                 \
 743         __cu_len = __invoke_copy_from_user_inatomic(__cu_to, __cu_from, \
 744                                                     __cu_len);          \
 745         __cu_len;                                                       \
 746 })
 747
 748 /*
 749  * copy_to_user: - Copy a block of data into user space.
 750  * @to:   Destination address, in user space.
 751  * @from: Source address, in kernel space.
 752  * @n:    Number of bytes to copy.
 753  *
 754  * Context: User context only.  This function may sleep.
 755  *
 756  * Copy data from kernel space to user space.
 757  *
 758  * Returns number of bytes that could not be copied.
 759  * On success, this will be zero.
 760  */
 761 #define copy_to_user(to, from, n)                                       \
 762 ({                                                                      \
 763         void __user *__cu_to;                                           \
 764         const void *__cu_from;                                          \
 765         long __cu_len;                                                  \
 766                                                                         \
 767         might_sleep();                                                  \
 768         __cu_to = (to);                                                 \
 769         __cu_from = (from);                                             \
 770         __cu_len = (n);                                                 \
 771         if (access_ok(VERIFY_WRITE, __cu_to, __cu_len))                 \
 772                 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from,    \
 773                                                  __cu_len);             \
 774         __cu_len;                                                       \
 775 })
 776
 777 #define __invoke_copy_from_user(to, from, n)                            \
 778 ({                                                                      \
 779         register void *__cu_to_r __asm__("$4");                         \
 780         register const void __user *__cu_from_r __asm__("$5");          \
 781         register long __cu_len_r __asm__("$6");                         \
 782                                                                         \
 783         __cu_to_r = (to);                                               \
 784         __cu_from_r = (from);                                           \
 785         __cu_len_r = (n);                                               \
 786         __asm__ __volatile__(                                           \
 787         ".set\tnoreorder\n\t"                                           \
 788         __MODULE_JAL(__copy_user)                                       \
 789         ".set\tnoat\n\t"                                                \
 790         __UA_ADDU "\t$1, %1, %2\n\t"                                    \
 791         ".set\tat\n\t"                                                  \
 792         ".set\treorder"                                                 \
 793         : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)       \
 794         :                                                               \
 795         : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",         \
 796           DADDI_SCRATCH, "memory");                                     \
 797         __cu_len_r;                                                     \
 798 })
 799
 800 #define __invoke_copy_from_user_inatomic(to, from, n)                   \
 801 ({                                                                      \
 802         register void *__cu_to_r __asm__("$4");                         \
 803         register const void __user *__cu_from_r __asm__("$5");          \
 804         register long __cu_len_r __asm__("$6");                         \
 805                                                                         \
 806         __cu_to_r = (to);                                               \
 807         __cu_from_r = (from);                                           \
 808         __cu_len_r = (n);                                               \
 809         __asm__ __volatile__(                                           \
 810         ".set\tnoreorder\n\t"                                           \
 811         __MODULE_JAL(__copy_user_inatomic)                              \
 812         ".set\tnoat\n\t"                                                \
 813         __UA_ADDU "\t$1, %1, %2\n\t"                                    \
 814         ".set\tat\n\t"                                                  \
 815         ".set\treorder"                                                 \
 816         : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)       \
 817         :                                                               \
 818         : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",         \
 819           DADDI_SCRATCH, "memory");                                     \
 820         __cu_len_r;                                                     \
 821 })
 822
 823 /*
 824  * __copy_from_user: - Copy a block of data from user space, with less checking.
 825  * @to:   Destination address, in kernel space.
 826  * @from: Source address, in user space.
 827  * @n:    Number of bytes to copy.
 828  *
 829  * Context: User context only.  This function may sleep.
 830  *
 831  * Copy data from user space to kernel space.  Caller must check
 832  * the specified block with access_ok() before calling this function.
 833  *
 834  * Returns number of bytes that could not be copied.
 835  * On success, this will be zero.
 836  *
 837  * If some data could not be copied, this function will pad the copied
 838  * data to the requested size using zero bytes.
 839  */
 840 #define __copy_from_user(to, from, n)                                   \
 841 ({                                                                      \
 842         void *__cu_to;                                                  \
 843         const void __user *__cu_from;                                   \
 844         long __cu_len;                                                  \
 845                                                                         \
 846         might_sleep();                                                  \
 847         __cu_to = (to);                                                 \
 848         __cu_from = (from);                                             \
 849         __cu_len = (n);                                                 \
 850         __cu_len = __invoke_copy_from_user(__cu_to, __cu_from,          \
 851                                            __cu_len);                   \
 852         __cu_len;                                                       \
 853 })
 854
 855 /*
 856  * copy_from_user: - Copy a block of data from user space.
 857  * @to:   Destination address, in kernel space.
 858  * @from: Source address, in user space.
 859  * @n:    Number of bytes to copy.
 860  *
 861  * Context: User context only.  This function may sleep.
 862  *
 863  * Copy data from user space to kernel space.
 864  *
 865  * Returns number of bytes that could not be copied.
 866  * On success, this will be zero.
 867  *
 868  * If some data could not be copied, this function will pad the copied
 869  * data to the requested size using zero bytes.
 870  */
 871 #define copy_from_user(to, from, n)                                     \
 872 ({                                                                      \
 873         void *__cu_to;                                                  \
 874         const void __user *__cu_from;                                   \
 875         long __cu_len;                                                  \
 876                                                                         \
 877         might_sleep();                                                  \
 878         __cu_to = (to);                                                 \
 879         __cu_from = (from);                                             \
 880         __cu_len = (n);                                                 \
 881         if (access_ok(VERIFY_READ, __cu_from, __cu_len))                \
 882                 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from,  \
 883                                                    __cu_len);           \
 884         __cu_len;                                                       \
 885 })
 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         __cu_len = __invoke_copy_from_user(__cu_to, __cu_from,          \
 898                                            __cu_len);                   \
 899         __cu_len;                                                       \
 900 })
 901
 902 #define copy_in_user(to, from, n)                                       \
 903 ({                                                                      \
 904         void __user *__cu_to;                                           \
 905         const void __user *__cu_from;                                   \
 906         long __cu_len;                                                  \
 907                                                                         \
 908         might_sleep();                                                  \
 909         __cu_to = (to);                                                 \
 910         __cu_from = (from);                                             \
 911         __cu_len = (n);                                                 \
 912         if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&       \
 913                    access_ok(VERIFY_WRITE, __cu_to, __cu_len)))         \
 914                 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from,  \
 915                                                    __cu_len);           \
 916         __cu_len;                                                       \
 917 })
 918
 919 /*
 920  * __clear_user: - Zero a block of memory in user space, with less checking.
 921  * @to:   Destination address, in user space.
 922  * @n:    Number of bytes to zero.
 923  *
 924  * Zero a block of memory in user space.  Caller must check
 925  * the specified block with access_ok() before calling this function.
 926  *
 927  * Returns number of bytes that could not be cleared.
 928  * On success, this will be zero.
 929  */
 930 static inline __kernel_size_t
 931 __clear_user(void __user *addr, __kernel_size_t size)
 932 {
 933         __kernel_size_t res;
 934
 935         might_sleep();
 936         __asm__ __volatile__(
 937                 "move\t$4, %1\n\t"
 938                 "move\t$5, $0\n\t"
 939                 "move\t$6, %2\n\t"
 940                 __MODULE_JAL(__bzero)
 941                 "move\t%0, $6"
 942                 : "=r" (res)
 943                 : "r" (addr), "r" (size)
 944                 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
 945
 946         return res;
 947 }
 948
 949 #define clear_user(addr,n)                                              \
 950 ({                                                                      \
 951         void __user * __cl_addr = (addr);                               \
 952         unsigned long __cl_size = (n);                                  \
 953         if (__cl_size && access_ok(VERIFY_WRITE,                        \
 954                 ((unsigned long)(__cl_addr)), __cl_size))               \
 955                 __cl_size = __clear_user(__cl_addr, __cl_size);         \
 956         __cl_size;                                                      \
 957 })
 958
 959 /*
 960  * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
 961  * @dst:   Destination address, in kernel space.  This buffer must be at
 962  *         least @count bytes long.
 963  * @src:   Source address, in user space.
 964  * @count: Maximum number of bytes to copy, including the trailing NUL.
 965  *
 966  * Copies a NUL-terminated string from userspace to kernel space.
 967  * Caller must check the specified block with access_ok() before calling
 968  * this function.
 969  *
 970  * On success, returns the length of the string (not including the trailing
 971  * NUL).
 972  *
 973  * If access to userspace fails, returns -EFAULT (some data may have been
 974  * copied).
 975  *
 976  * If @count is smaller than the length of the string, copies @count bytes
 977  * and returns @count.
 978  */
 979 static inline long
 980 __strncpy_from_user(char *__to, const char __user *__from, long __len)
 981 {
 982         long res;
 983
 984         might_sleep();
 985         __asm__ __volatile__(
 986                 "move\t$4, %1\n\t"
 987                 "move\t$5, %2\n\t"
 988                 "move\t$6, %3\n\t"
 989                 __MODULE_JAL(__strncpy_from_user_nocheck_asm)
 990                 "move\t%0, $2"
 991                 : "=r" (res)
 992                 : "r" (__to), "r" (__from), "r" (__len)
 993                 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
 994
 995         return res;
 996 }
 997
 998 /*
 999  * strncpy_from_user: - Copy a NUL terminated string from userspace.
1000  * @dst:   Destination address, in kernel space.  This buffer must be at
1001  *         least @count bytes long.
1002  * @src:   Source address, in user space.
1003  * @count: Maximum number of bytes to copy, including the trailing NUL.
1004  *
1005  * Copies a NUL-terminated string from userspace to kernel space.
1006  *
1007  * On success, returns the length of the string (not including the trailing
1008  * NUL).
1009  *
1010  * If access to userspace fails, returns -EFAULT (some data may have been
1011  * copied).
1012  *
1013  * If @count is smaller than the length of the string, copies @count bytes
1014  * and returns @count.
1015  */
1016 static inline long
1017 strncpy_from_user(char *__to, const char __user *__from, long __len)
1018 {
1019         long res;
1020
1021         might_sleep();
1022         __asm__ __volatile__(
1023                 "move\t$4, %1\n\t"
1024                 "move\t$5, %2\n\t"
1025                 "move\t$6, %3\n\t"
1026                 __MODULE_JAL(__strncpy_from_user_asm)
1027                 "move\t%0, $2"
1028                 : "=r" (res)
1029                 : "r" (__to), "r" (__from), "r" (__len)
1030                 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1031
1032         return res;
1033 }
1034
1035 /* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1036 static inline long __strlen_user(const char __user *s)
1037 {
1038         long res;
1039
1040         might_sleep();
1041         __asm__ __volatile__(
1042                 "move\t$4, %1\n\t"
1043                 __MODULE_JAL(__strlen_user_nocheck_asm)
1044                 "move\t%0, $2"
1045                 : "=r" (res)
1046                 : "r" (s)
1047                 : "$2", "$4", __UA_t0, "$31");
1048
1049         return res;
1050 }
1051
1052 /*
1053  * strlen_user: - Get the size of a string in user space.
1054  * @str: The string to measure.
1055  *
1056  * Context: User context only.  This function may sleep.
1057  *
1058  * Get the size of a NUL-terminated string in user space.
1059  *
1060  * Returns the size of the string INCLUDING the terminating NUL.
1061  * On exception, returns 0.
1062  *
1063  * If there is a limit on the length of a valid string, you may wish to
1064  * consider using strnlen_user() instead.
1065  */
1066 static inline long strlen_user(const char __user *s)
1067 {
1068         long res;
1069
1070         might_sleep();
1071         __asm__ __volatile__(
1072                 "move\t$4, %1\n\t"
1073                 __MODULE_JAL(__strlen_user_asm)
1074                 "move\t%0, $2"
1075                 : "=r" (res)
1076                 : "r" (s)
1077                 : "$2", "$4", __UA_t0, "$31");
1078
1079         return res;
1080 }
1081
1082 /* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1083 static inline long __strnlen_user(const char __user *s, long n)
1084 {
1085         long res;
1086
1087         might_sleep();
1088         __asm__ __volatile__(
1089                 "move\t$4, %1\n\t"
1090                 "move\t$5, %2\n\t"
1091                 __MODULE_JAL(__strnlen_user_nocheck_asm)
1092                 "move\t%0, $2"
1093                 : "=r" (res)
1094                 : "r" (s), "r" (n)
1095                 : "$2", "$4", "$5", __UA_t0, "$31");
1096
1097         return res;
1098 }
1099
1100 /*
1101  * strlen_user: - Get the size of a string in user space.
1102  * @str: The string to measure.
1103  *
1104  * Context: User context only.  This function may sleep.
1105  *
1106  * Get the size of a NUL-terminated string in user space.
1107  *
1108  * Returns the size of the string INCLUDING the terminating NUL.
1109  * On exception, returns 0.
1110  *
1111  * If there is a limit on the length of a valid string, you may wish to
1112  * consider using strnlen_user() instead.
1113  */
1114 static inline long strnlen_user(const char __user *s, long n)
1115 {
1116         long res;
1117
1118         might_sleep();
1119         __asm__ __volatile__(
1120                 "move\t$4, %1\n\t"
1121                 "move\t$5, %2\n\t"
1122                 __MODULE_JAL(__strnlen_user_asm)
1123                 "move\t%0, $2"
1124                 : "=r" (res)
1125                 : "r" (s), "r" (n)
1126                 : "$2", "$4", "$5", __UA_t0, "$31");
1127
1128         return res;
1129 }
1130
1131 struct exception_table_entry
1132 {
1133         unsigned long insn;
1134         unsigned long nextinsn;
1135 };
1136
1137 extern int fixup_exception(struct pt_regs *regs);
1138
1139 #endif /* _ASM_UACCESS_H */