include/asm-m32r/uaccess.h

   1 #ifndef _ASM_M32R_UACCESS_H
   2 #define _ASM_M32R_UACCESS_H
   3
   4 /*
   5  *  linux/include/asm-m32r/uaccess.h
   6  *
   7  *  M32R version.
   8  *    Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
   9  */
  10
  11 #undef UACCESS_DEBUG
  12
  13 #ifdef UACCESS_DEBUG
  14 #define UAPRINTK(args...) printk(args)
  15 #else
  16 #define UAPRINTK(args...)
  17 #endif /* UACCESS_DEBUG */
  18
  19 /*
  20  * User space memory access functions
  21  */
  22 #include <linux/config.h>
  23 #include <linux/errno.h>
  24 #include <linux/thread_info.h>
  25 #include <asm/page.h>
  26
  27 #define VERIFY_READ 0
  28 #define VERIFY_WRITE 1
  29
  30 /*
  31  * The fs value determines whether argument validity checking should be
  32  * performed or not.  If get_fs() == USER_DS, checking is performed, with
  33  * get_fs() == KERNEL_DS, checking is bypassed.
  34  *
  35  * For historical reasons, these macros are grossly misnamed.
  36  */
  37
  38 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
  39
  40 #ifdef CONFIG_MMU
  41 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
  42 #define USER_DS         MAKE_MM_SEG(PAGE_OFFSET)
  43 #else
  44 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
  45 #define USER_DS         MAKE_MM_SEG(0xFFFFFFFF)
  46 #endif /* CONFIG_MMU */
  47
  48 #define get_ds()        (KERNEL_DS)
  49 #ifdef CONFIG_MMU
  50 #define get_fs()        (current_thread_info()->addr_limit)
  51 #define set_fs(x)       (current_thread_info()->addr_limit = (x))
  52 #else
  53 static inline mm_segment_t get_fs(void)
  54 {
  55   return USER_DS;
  56 }
  57
  58 static inline void set_fs(mm_segment_t s)
  59 {
  60 }
  61 #endif /* CONFIG_MMU */
  62
  63 #define segment_eq(a,b) ((a).seg == (b).seg)
  64
  65 #define __addr_ok(addr) \
  66         ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
  67
  68 /*
  69  * Test whether a block of memory is a valid user space address.
  70  * Returns 0 if the range is valid, nonzero otherwise.
  71  *
  72  * This is equivalent to the following test:
  73  * (u33)addr + (u33)size >= (u33)current->addr_limit.seg
  74  *
  75  * This needs 33-bit arithmetic. We have a carry...
  76  */
  77 #define __range_ok(addr,size) ({                                        \
  78         unsigned long flag, sum;                                        \
  79         __chk_user_ptr(addr);                                           \
  80         asm (                                                           \
  81                 "       cmpu    %1, %1    ; clear cbit\n"               \
  82                 "       addx    %1, %3    ; set cbit if overflow\n"     \
  83                 "       subx    %0, %0\n"                               \
  84                 "       cmpu    %4, %1\n"                               \
  85                 "       subx    %0, %5\n"                               \
  86                 : "=&r"(flag), "=r"(sum)                                \
  87                 : "1"(addr), "r"((int)(size)),                          \
  88                   "r"(current_thread_info()->addr_limit.seg), "r"(0)    \
  89                 : "cbit" );                                             \
  90         flag; })
  91
  92 /**
  93  * access_ok: - Checks if a user space pointer is valid
  94  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
  95  *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
  96  *        to write to a block, it is always safe to read from it.
  97  * @addr: User space pointer to start of block to check
  98  * @size: Size of block to check
  99  *
 100  * Context: User context only.  This function may sleep.
 101  *
 102  * Checks if a pointer to a block of memory in user space is valid.
 103  *
 104  * Returns true (nonzero) if the memory block may be valid, false (zero)
 105  * if it is definitely invalid.
 106  *
 107  * Note that, depending on architecture, this function probably just
 108  * checks that the pointer is in the user space range - after calling
 109  * this function, memory access functions may still return -EFAULT.
 110  */
 111 #ifdef CONFIG_MMU
 112 #define access_ok(type,addr,size) (likely(__range_ok(addr,size) == 0))
 113 #else
 114 static inline int access_ok(int type, const void *addr, unsigned long size)
 115 {
 116   extern unsigned long memory_start, memory_end;
 117   unsigned long val = (unsigned long)addr;
 118
 119   return ((val >= memory_start) && ((val + size) < memory_end));
 120 }
 121 #endif /* CONFIG_MMU */
 122
 123 /**
 124  * verify_area: - Obsolete/deprecated and will go away soon,
 125  * use access_ok() instead.
 126  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE
 127  * @addr: User space pointer to start of block to check
 128  * @size: Size of block to check
 129  *
 130  * Context: User context only.  This function may sleep.
 131  *
 132  * This function has been replaced by access_ok().
 133  *
 134  * Checks if a pointer to a block of memory in user space is valid.
 135  *
 136  * Returns zero if the memory block may be valid, -EFAULT
 137  * if it is definitely invalid.
 138  *
 139  * See access_ok() for more details.
 140  */
 141 static inline int __deprecated verify_area(int type, const void __user *addr,
 142                               unsigned long size)
 143 {
 144         return access_ok(type, addr, size) ? 0 : -EFAULT;
 145 }
 146
 147
 148 /*
 149  * The exception table consists of pairs of addresses: the first is the
 150  * address of an instruction that is allowed to fault, and the second is
 151  * the address at which the program should continue.  No registers are
 152  * modified, so it is entirely up to the continuation code to figure out
 153  * what to do.
 154  *
 155  * All the routines below use bits of fixup code that are out of line
 156  * with the main instruction path.  This means when everything is well,
 157  * we don't even have to jump over them.  Further, they do not intrude
 158  * on our cache or tlb entries.
 159  */
 160
 161 struct exception_table_entry
 162 {
 163         unsigned long insn, fixup;
 164 };
 165
 166 extern int fixup_exception(struct pt_regs *regs);
 167
 168 /*
 169  * These are the main single-value transfer routines.  They automatically
 170  * use the right size if we just have the right pointer type.
 171  *
 172  * This gets kind of ugly. We want to return _two_ values in "get_user()"
 173  * and yet we don't want to do any pointers, because that is too much
 174  * of a performance impact. Thus we have a few rather ugly macros here,
 175  * and hide all the uglyness from the user.
 176  *
 177  * The "__xxx" versions of the user access functions are versions that
 178  * do not verify the address space, that must have been done previously
 179  * with a separate "access_ok()" call (this is used when we do multiple
 180  * accesses to the same area of user memory).
 181  */
 182
 183 extern void __get_user_1(void);
 184 extern void __get_user_2(void);
 185 extern void __get_user_4(void);
 186
 187 #ifndef MODULE
 188 #define __get_user_x(size,ret,x,ptr)                                    \
 189         __asm__ __volatile__(                                           \
 190                 "       mv      r0, %0\n"                               \
 191                 "       mv      r1, %1\n"                               \
 192                 "       bl __get_user_" #size "\n"                      \
 193                 "       mv      %0, r0\n"                               \
 194                 "       mv      %1, r1\n"                               \
 195                 : "=r"(ret), "=r"(x)                                    \
 196                 : "0"(ptr)                                              \
 197                 : "r0", "r1", "r14" )
 198 #else /* MODULE */
 199 /*
 200  * Use "jl" instead of "bl" for MODULE
 201  */
 202 #define __get_user_x(size,ret,x,ptr)                                    \
 203         __asm__ __volatile__(                                           \
 204                 "       mv      r0, %0\n"                               \
 205                 "       mv      r1, %1\n"                               \
 206                 "       seth    lr, #high(__get_user_" #size ")\n"      \
 207                 "       or3     lr, lr, #low(__get_user_" #size ")\n"   \
 208                 "       jl      lr\n"                                   \
 209                 "       mv      %0, r0\n"                               \
 210                 "       mv      %1, r1\n"                               \
 211                 : "=r"(ret), "=r"(x)                                    \
 212                 : "0"(ptr)                                              \
 213                 : "r0", "r1", "r14" )
 214 #endif
 215
 216 /* Careful: we have to cast the result to the type of the pointer for sign
 217    reasons */
 218 /**
 219  * get_user: - Get a simple variable from user space.
 220  * @x:   Variable to store result.
 221  * @ptr: Source address, in user space.
 222  *
 223  * Context: User context only.  This function may sleep.
 224  *
 225  * This macro copies a single simple variable from user space to kernel
 226  * space.  It supports simple types like char and int, but not larger
 227  * data types like structures or arrays.
 228  *
 229  * @ptr must have pointer-to-simple-variable type, and the result of
 230  * dereferencing @ptr must be assignable to @x without a cast.
 231  *
 232  * Returns zero on success, or -EFAULT on error.
 233  * On error, the variable @x is set to zero.
 234  */
 235 #define get_user(x,ptr)                                                 \
 236 ({      int __ret_gu,__val_gu;                                          \
 237         __chk_user_ptr(ptr);                                            \
 238         switch(sizeof (*(ptr))) {                                       \
 239         case 1:  __get_user_x(1,__ret_gu,__val_gu,ptr); break;          \
 240         case 2:  __get_user_x(2,__ret_gu,__val_gu,ptr); break;          \
 241         case 4:  __get_user_x(4,__ret_gu,__val_gu,ptr); break;          \
 242         default: __get_user_x(X,__ret_gu,__val_gu,ptr); break;          \
 243         }                                                               \
 244         (x) = (__typeof__(*(ptr)))__val_gu;                             \
 245         __ret_gu;                                                       \
 246 })
 247
 248 extern void __put_user_bad(void);
 249
 250 /**
 251  * put_user: - Write a simple value into user space.
 252  * @x:   Value to copy to user space.
 253  * @ptr: Destination address, in user space.
 254  *
 255  * Context: User context only.  This function may sleep.
 256  *
 257  * This macro copies a single simple value from kernel space to user
 258  * space.  It supports simple types like char and int, but not larger
 259  * data types like structures or arrays.
 260  *
 261  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 262  * to the result of dereferencing @ptr.
 263  *
 264  * Returns zero on success, or -EFAULT on error.
 265  */
 266 #define put_user(x,ptr)                                                 \
 267   __put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
 268
 269
 270 /**
 271  * __get_user: - Get a simple variable from user space, with less checking.
 272  * @x:   Variable to store result.
 273  * @ptr: Source address, in user space.
 274  *
 275  * Context: User context only.  This function may sleep.
 276  *
 277  * This macro copies a single simple variable from user space to kernel
 278  * space.  It supports simple types like char and int, but not larger
 279  * data types like structures or arrays.
 280  *
 281  * @ptr must have pointer-to-simple-variable type, and the result of
 282  * dereferencing @ptr must be assignable to @x without a cast.
 283  *
 284  * Caller must check the pointer with access_ok() before calling this
 285  * function.
 286  *
 287  * Returns zero on success, or -EFAULT on error.
 288  * On error, the variable @x is set to zero.
 289  */
 290 #define __get_user(x,ptr) \
 291   __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
 292
 293
 294 /**
 295  * __put_user: - Write a simple value into user space, with less checking.
 296  * @x:   Value to copy to user space.
 297  * @ptr: Destination address, in user space.
 298  *
 299  * Context: User context only.  This function may sleep.
 300  *
 301  * This macro copies a single simple value from kernel space to user
 302  * space.  It supports simple types like char and int, but not larger
 303  * data types like structures or arrays.
 304  *
 305  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 306  * to the result of dereferencing @ptr.
 307  *
 308  * Caller must check the pointer with access_ok() before calling this
 309  * function.
 310  *
 311  * Returns zero on success, or -EFAULT on error.
 312  */
 313 #define __put_user(x,ptr) \
 314   __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
 315
 316 #define __put_user_nocheck(x,ptr,size)                                  \
 317 ({                                                                      \
 318         long __pu_err;                                                  \
 319         __put_user_size((x),(ptr),(size),__pu_err);                     \
 320         __pu_err;                                                       \
 321 })
 322
 323
 324 #define __put_user_check(x,ptr,size)                                    \
 325 ({                                                                      \
 326         long __pu_err = -EFAULT;                                        \
 327         __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
 328         might_sleep();                                                  \
 329         if (access_ok(VERIFY_WRITE,__pu_addr,size))                     \
 330                 __put_user_size((x),__pu_addr,(size),__pu_err);         \
 331         __pu_err;                                                       \
 332 })
 333
 334 #if defined(__LITTLE_ENDIAN__)
 335 #define __put_user_u64(x, addr, err)                                    \
 336         __asm__ __volatile__(                                           \
 337                 "       .fillinsn\n"                                    \
 338                 "1:     st %L1,@%2\n"                                    \
 339                 "       .fillinsn\n"                                    \
 340                 "2:     st %H1,@(4,%2)\n"                                \
 341                 "       .fillinsn\n"                                    \
 342                 "3:\n"                                                  \
 343                 ".section .fixup,\"ax\"\n"                              \
 344                 "       .balign 4\n"                                    \
 345                 "4:     ldi %0,%3\n"                                    \
 346                 "       seth r14,#high(3b)\n"                           \
 347                 "       or3 r14,r14,#low(3b)\n"                         \
 348                 "       jmp r14\n"                                      \
 349                 ".previous\n"                                           \
 350                 ".section __ex_table,\"a\"\n"                           \
 351                 "       .balign 4\n"                                    \
 352                 "       .long 1b,4b\n"                                  \
 353                 "       .long 2b,4b\n"                                  \
 354                 ".previous"                                             \
 355                 : "=r"(err)                                             \
 356                 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)             \
 357                 : "r14", "memory")
 358
 359 #elif defined(__BIG_ENDIAN__)
 360 #define __put_user_u64(x, addr, err)                                    \
 361         __asm__ __volatile__(                                           \
 362                 "       .fillinsn\n"                                    \
 363                 "1:     st %H1,@%2\n"                                   \
 364                 "       .fillinsn\n"                                    \
 365                 "2:     st %L1,@(4,%2)\n"                               \
 366                 "       .fillinsn\n"                                    \
 367                 "3:\n"                                                  \
 368                 ".section .fixup,\"ax\"\n"                              \
 369                 "       .balign 4\n"                                    \
 370                 "4:     ldi %0,%3\n"                                    \
 371                 "       seth r14,#high(3b)\n"                           \
 372                 "       or3 r14,r14,#low(3b)\n"                         \
 373                 "       jmp r14\n"                                      \
 374                 ".previous\n"                                           \
 375                 ".section __ex_table,\"a\"\n"                           \
 376                 "       .balign 4\n"                                    \
 377                 "       .long 1b,4b\n"                                  \
 378                 "       .long 2b,4b\n"                                  \
 379                 ".previous"                                             \
 380                 : "=r"(err)                                             \
 381                 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)             \
 382                 : "r14", "memory")
 383 #else
 384 #error no endian defined
 385 #endif
 386
 387 #define __put_user_size(x,ptr,size,retval)                              \
 388 do {                                                                    \
 389         retval = 0;                                                     \
 390         __chk_user_ptr(ptr);                                            \
 391         switch (size) {                                                 \
 392           case 1: __put_user_asm(x,ptr,retval,"b"); break;              \
 393           case 2: __put_user_asm(x,ptr,retval,"h"); break;              \
 394           case 4: __put_user_asm(x,ptr,retval,""); break;               \
 395           case 8: __put_user_u64((__typeof__(*ptr))(x),ptr,retval); break;\
 396           default: __put_user_bad();                                    \
 397         }                                                               \
 398 } while (0)
 399
 400 struct __large_struct { unsigned long buf[100]; };
 401 #define __m(x) (*(struct __large_struct *)(x))
 402
 403 /*
 404  * Tell gcc we read from memory instead of writing: this is because
 405  * we do not write to any memory gcc knows about, so there are no
 406  * aliasing issues.
 407  */
 408 #define __put_user_asm(x, addr, err, itype)                             \
 409         __asm__ __volatile__(                                           \
 410                 "       .fillinsn\n"                                    \
 411                 "1:     st"itype" %1,@%2\n"                             \
 412                 "       .fillinsn\n"                                    \
 413                 "2:\n"                                                  \
 414                 ".section .fixup,\"ax\"\n"                              \
 415                 "       .balign 4\n"                                    \
 416                 "3:     ldi %0,%3\n"                                    \
 417                 "       seth r14,#high(2b)\n"                           \
 418                 "       or3 r14,r14,#low(2b)\n"                         \
 419                 "       jmp r14\n"                                      \
 420                 ".previous\n"                                           \
 421                 ".section __ex_table,\"a\"\n"                           \
 422                 "       .balign 4\n"                                    \
 423                 "       .long 1b,3b\n"                                  \
 424                 ".previous"                                             \
 425                 : "=r"(err)                                             \
 426                 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)             \
 427                 : "r14", "memory")
 428
 429 #define __get_user_nocheck(x,ptr,size)                                  \
 430 ({                                                                      \
 431         long __gu_err, __gu_val;                                        \
 432         __get_user_size(__gu_val,(ptr),(size),__gu_err);                \
 433         (x) = (__typeof__(*(ptr)))__gu_val;                             \
 434         __gu_err;                                                       \
 435 })
 436
 437 extern long __get_user_bad(void);
 438
 439 #define __get_user_size(x,ptr,size,retval)                              \
 440 do {                                                                    \
 441         retval = 0;                                                     \
 442         __chk_user_ptr(ptr);                                            \
 443         switch (size) {                                                 \
 444           case 1: __get_user_asm(x,ptr,retval,"ub"); break;             \
 445           case 2: __get_user_asm(x,ptr,retval,"uh"); break;             \
 446           case 4: __get_user_asm(x,ptr,retval,""); break;               \
 447           default: (x) = __get_user_bad();                              \
 448         }                                                               \
 449 } while (0)
 450
 451 #define __get_user_asm(x, addr, err, itype)                             \
 452         __asm__ __volatile__(                                           \
 453                 "       .fillinsn\n"                                    \
 454                 "1:     ld"itype" %1,@%2\n"                             \
 455                 "       .fillinsn\n"                                    \
 456                 "2:\n"                                                  \
 457                 ".section .fixup,\"ax\"\n"                              \
 458                 "       .balign 4\n"                                    \
 459                 "3:     ldi %0,%3\n"                                    \
 460                 "       seth r14,#high(2b)\n"                           \
 461                 "       or3 r14,r14,#low(2b)\n"                         \
 462                 "       jmp r14\n"                                      \
 463                 ".previous\n"                                           \
 464                 ".section __ex_table,\"a\"\n"                           \
 465                 "       .balign 4\n"                                    \
 466                 "       .long 1b,3b\n"                                  \
 467                 ".previous"                                             \
 468                 : "=r"(err), "=&r"(x)                                   \
 469                 : "r"(addr), "i"(-EFAULT), "0"(err)                     \
 470                 : "r14", "memory")
 471
 472 /*
 473  * Here we special-case 1, 2 and 4-byte copy_*_user invocations.  On a fault
 474  * we return the initial request size (1, 2 or 4), as copy_*_user should do.
 475  * If a store crosses a page boundary and gets a fault, the m32r will not write
 476  * anything, so this is accurate.
 477  */
 478
 479
 480 /*
 481  * Copy To/From Userspace
 482  */
 483
 484 /* Generic arbitrary sized copy.  */
 485 /* Return the number of bytes NOT copied.  */
 486 #define __copy_user(to,from,size)                                       \
 487 do {                                                                    \
 488         unsigned long __dst, __src, __c;                                \
 489         __asm__ __volatile__ (                                          \
 490                 "       mv      r14, %0\n"                              \
 491                 "       or      r14, %1\n"                              \
 492                 "       beq     %0, %1, 9f\n"                           \
 493                 "       beqz    %2, 9f\n"                               \
 494                 "       and3    r14, r14, #3\n"                         \
 495                 "       bnez    r14, 2f\n"                              \
 496                 "       and3    %2, %2, #3\n"                           \
 497                 "       beqz    %3, 2f\n"                               \
 498                 "       addi    %0, #-4         ; word_copy \n"         \
 499                 "       .fillinsn\n"                                    \
 500                 "0:     ld      r14, @%1+\n"                            \
 501                 "       addi    %3, #-1\n"                              \
 502                 "       .fillinsn\n"                                    \
 503                 "1:     st      r14, @+%0\n"                            \
 504                 "       bnez    %3, 0b\n"                               \
 505                 "       beqz    %2, 9f\n"                               \
 506                 "       addi    %0, #4\n"                               \
 507                 "       .fillinsn\n"                                    \
 508                 "2:     ldb     r14, @%1        ; byte_copy \n"         \
 509                 "       .fillinsn\n"                                    \
 510                 "3:     stb     r14, @%0\n"                             \
 511                 "       addi    %1, #1\n"                               \
 512                 "       addi    %2, #-1\n"                              \
 513                 "       addi    %0, #1\n"                               \
 514                 "       bnez    %2, 2b\n"                               \
 515                 "       .fillinsn\n"                                    \
 516                 "9:\n"                                                  \
 517                 ".section .fixup,\"ax\"\n"                              \
 518                 "       .balign 4\n"                                    \
 519                 "5:     addi    %3, #1\n"                               \
 520                 "       addi    %1, #-4\n"                              \
 521                 "       .fillinsn\n"                                    \
 522                 "6:     slli    %3, #2\n"                               \
 523                 "       add     %2, %3\n"                               \
 524                 "       addi    %0, #4\n"                               \
 525                 "       .fillinsn\n"                                    \
 526                 "7:     seth    r14, #high(9b)\n"                       \
 527                 "       or3     r14, r14, #low(9b)\n"                   \
 528                 "       jmp     r14\n"                                  \
 529                 ".previous\n"                                           \
 530                 ".section __ex_table,\"a\"\n"                           \
 531                 "       .balign 4\n"                                    \
 532                 "       .long 0b,6b\n"                                  \
 533                 "       .long 1b,5b\n"                                  \
 534                 "       .long 2b,9b\n"                                  \
 535                 "       .long 3b,9b\n"                                  \
 536                 ".previous\n"                                           \
 537                 : "=&r"(__dst), "=&r"(__src), "=&r"(size), "=&r"(__c)   \
 538                 : "0"(to), "1"(from), "2"(size), "3"(size / 4)          \
 539                 : "r14", "memory");                                     \
 540 } while (0)
 541
 542 #define __copy_user_zeroing(to,from,size)                               \
 543 do {                                                                    \
 544         unsigned long __dst, __src, __c;                                \
 545         __asm__ __volatile__ (                                          \
 546                 "       mv      r14, %0\n"                              \
 547                 "       or      r14, %1\n"                              \
 548                 "       beq     %0, %1, 9f\n"                           \
 549                 "       beqz    %2, 9f\n"                               \
 550                 "       and3    r14, r14, #3\n"                         \
 551                 "       bnez    r14, 2f\n"                              \
 552                 "       and3    %2, %2, #3\n"                           \
 553                 "       beqz    %3, 2f\n"                               \
 554                 "       addi    %0, #-4         ; word_copy \n"         \
 555                 "       .fillinsn\n"                                    \
 556                 "0:     ld      r14, @%1+\n"                            \
 557                 "       addi    %3, #-1\n"                              \
 558                 "       .fillinsn\n"                                    \
 559                 "1:     st      r14, @+%0\n"                            \
 560                 "       bnez    %3, 0b\n"                               \
 561                 "       beqz    %2, 9f\n"                               \
 562                 "       addi    %0, #4\n"                               \
 563                 "       .fillinsn\n"                                    \
 564                 "2:     ldb     r14, @%1        ; byte_copy \n"         \
 565                 "       .fillinsn\n"                                    \
 566                 "3:     stb     r14, @%0\n"                             \
 567                 "       addi    %1, #1\n"                               \
 568                 "       addi    %2, #-1\n"                              \
 569                 "       addi    %0, #1\n"                               \
 570                 "       bnez    %2, 2b\n"                               \
 571                 "       .fillinsn\n"                                    \
 572                 "9:\n"                                                  \
 573                 ".section .fixup,\"ax\"\n"                              \
 574                 "       .balign 4\n"                                    \
 575                 "5:     addi    %3, #1\n"                               \
 576                 "       addi    %1, #-4\n"                              \
 577                 "       .fillinsn\n"                                    \
 578                 "6:     slli    %3, #2\n"                               \
 579                 "       add     %2, %3\n"                               \
 580                 "       addi    %0, #4\n"                               \
 581                 "       .fillinsn\n"                                    \
 582                 "7:     ldi     r14, #0         ; store zero \n"        \
 583                 "       .fillinsn\n"                                    \
 584                 "8:     addi    %2, #-1\n"                              \
 585                 "       stb     r14, @%0        ; ACE? \n"              \
 586                 "       addi    %0, #1\n"                               \
 587                 "       bnez    %2, 8b\n"                               \
 588                 "       seth    r14, #high(9b)\n"                       \
 589                 "       or3     r14, r14, #low(9b)\n"                   \
 590                 "       jmp     r14\n"                                  \
 591                 ".previous\n"                                           \
 592                 ".section __ex_table,\"a\"\n"                           \
 593                 "       .balign 4\n"                                    \
 594                 "       .long 0b,6b\n"                                  \
 595                 "       .long 1b,5b\n"                                  \
 596                 "       .long 2b,7b\n"                                  \
 597                 "       .long 3b,7b\n"                                  \
 598                 ".previous\n"                                           \
 599                 : "=&r"(__dst), "=&r"(__src), "=&r"(size), "=&r"(__c)   \
 600                 : "0"(to), "1"(from), "2"(size), "3"(size / 4)          \
 601                 : "r14", "memory");                                     \
 602 } while (0)
 603
 604
 605 /* We let the __ versions of copy_from/to_user inline, because they're often
 606  * used in fast paths and have only a small space overhead.
 607  */
 608 static inline unsigned long __generic_copy_from_user_nocheck(void *to,
 609         const void __user *from, unsigned long n)
 610 {
 611         __copy_user_zeroing(to,from,n);
 612         return n;
 613 }
 614
 615 static inline unsigned long __generic_copy_to_user_nocheck(void __user *to,
 616         const void *from, unsigned long n)
 617 {
 618         __copy_user(to,from,n);
 619         return n;
 620 }
 621
 622 unsigned long __generic_copy_to_user(void *, const void *, unsigned long);
 623 unsigned long __generic_copy_from_user(void *, const void *, unsigned long);
 624
 625 /**
 626  * __copy_to_user: - Copy a block of data into user space, with less checking.
 627  * @to:   Destination address, in user space.
 628  * @from: Source address, in kernel space.
 629  * @n:    Number of bytes to copy.
 630  *
 631  * Context: User context only.  This function may sleep.
 632  *
 633  * Copy data from kernel space to user space.  Caller must check
 634  * the specified block with access_ok() before calling this function.
 635  *
 636  * Returns number of bytes that could not be copied.
 637  * On success, this will be zero.
 638  */
 639 #define __copy_to_user(to,from,n)                       \
 640         __generic_copy_to_user_nocheck((to),(from),(n))
 641
 642 #define __copy_to_user_inatomic __copy_to_user
 643 #define __copy_from_user_inatomic __copy_from_user
 644
 645 /**
 646  * copy_to_user: - Copy a block of data into user space.
 647  * @to:   Destination address, in user space.
 648  * @from: Source address, in kernel space.
 649  * @n:    Number of bytes to copy.
 650  *
 651  * Context: User context only.  This function may sleep.
 652  *
 653  * Copy data from kernel space to user space.
 654  *
 655  * Returns number of bytes that could not be copied.
 656  * On success, this will be zero.
 657  */
 658 #define copy_to_user(to,from,n)                         \
 659 ({                                                      \
 660         might_sleep();                                  \
 661         __generic_copy_to_user((to),(from),(n));        \
 662 })
 663
 664 /**
 665  * __copy_from_user: - Copy a block of data from user space, with less checking. * @to:   Destination address, in kernel space.
 666  * @from: Source address, in user space.
 667  * @n:    Number of bytes to copy.
 668  *
 669  * Context: User context only.  This function may sleep.
 670  *
 671  * Copy data from user space to kernel space.  Caller must check
 672  * the specified block with access_ok() before calling this function.
 673  *
 674  * Returns number of bytes that could not be copied.
 675  * On success, this will be zero.
 676  *
 677  * If some data could not be copied, this function will pad the copied
 678  * data to the requested size using zero bytes.
 679  */
 680 #define __copy_from_user(to,from,n)                     \
 681         __generic_copy_from_user_nocheck((to),(from),(n))
 682
 683 /**
 684  * copy_from_user: - Copy a block of data from user space.
 685  * @to:   Destination address, in kernel space.
 686  * @from: Source address, in user space.
 687  * @n:    Number of bytes to copy.
 688  *
 689  * Context: User context only.  This function may sleep.
 690  *
 691  * Copy data from user space to kernel space.
 692  *
 693  * Returns number of bytes that could not be copied.
 694  * On success, this will be zero.
 695  *
 696  * If some data could not be copied, this function will pad the copied
 697  * data to the requested size using zero bytes.
 698  */
 699 #define copy_from_user(to,from,n)                       \
 700 ({                                                      \
 701         might_sleep();                                  \
 702 __generic_copy_from_user((to),(from),(n));      \
 703 })
 704
 705 long __must_check strncpy_from_user(char *dst, const char __user *src,
 706                                 long count);
 707 long __must_check __strncpy_from_user(char *dst,
 708                                 const char __user *src, long count);
 709
 710 /**
 711  * __clear_user: - Zero a block of memory in user space, with less checking.
 712  * @to:   Destination address, in user space.
 713  * @n:    Number of bytes to zero.
 714  *
 715  * Zero a block of memory in user space.  Caller must check
 716  * the specified block with access_ok() before calling this function.
 717  *
 718  * Returns number of bytes that could not be cleared.
 719  * On success, this will be zero.
 720  */
 721 unsigned long __clear_user(void __user *mem, unsigned long len);
 722
 723 /**
 724  * clear_user: - Zero a block of memory in user space.
 725  * @to:   Destination address, in user space.
 726  * @n:    Number of bytes to zero.
 727  *
 728  * Zero a block of memory in user space.  Caller must check
 729  * the specified block with access_ok() before calling this function.
 730  *
 731  * Returns number of bytes that could not be cleared.
 732  * On success, this will be zero.
 733  */
 734 unsigned long clear_user(void __user *mem, unsigned long len);
 735
 736 /**
 737  * strlen_user: - Get the size of a string in user space.
 738  * @str: The string to measure.
 739  *
 740  * Context: User context only.  This function may sleep.
 741  *
 742  * Get the size of a NUL-terminated string in user space.
 743  *
 744  * Returns the size of the string INCLUDING the terminating NUL.
 745  * On exception, returns 0.
 746  *
 747  * If there is a limit on the length of a valid string, you may wish to
 748  * consider using strnlen_user() instead.
 749  */
 750 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
 751 long strnlen_user(const char __user *str, long n);
 752
 753 #endif /* _ASM_M32R_UACCESS_H */