linux/arch/x86/lib/usercopy_32.c
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   1/* 
   2 * User address space access functions.
   3 * The non inlined parts of asm-i386/uaccess.h are here.
   4 *
   5 * Copyright 1997 Andi Kleen <ak@muc.de>
   6 * Copyright 1997 Linus Torvalds
   7 */
   8#include <linux/mm.h>
   9#include <linux/highmem.h>
  10#include <linux/blkdev.h>
  11#include <linux/module.h>
  12#include <linux/backing-dev.h>
  13#include <linux/interrupt.h>
  14#include <asm/uaccess.h>
  15#include <asm/mmx.h>
  16
  17static inline int __movsl_is_ok(unsigned long a1, unsigned long a2, unsigned long n)
  18{
  19#ifdef CONFIG_X86_INTEL_USERCOPY
  20        if (n >= 64 && ((a1 ^ a2) & movsl_mask.mask))
  21                return 0;
  22#endif
  23        return 1;
  24}
  25#define movsl_is_ok(a1,a2,n) \
  26        __movsl_is_ok((unsigned long)(a1),(unsigned long)(a2),(n))
  27
  28/*
  29 * Copy a null terminated string from userspace.
  30 */
  31
  32#define __do_strncpy_from_user(dst,src,count,res)                          \
  33do {                                                                       \
  34        int __d0, __d1, __d2;                                              \
  35        might_sleep();                                                     \
  36        __asm__ __volatile__(                                              \
  37                "       testl %1,%1\n"                                     \
  38                "       jz 2f\n"                                           \
  39                "0:     lodsb\n"                                           \
  40                "       stosb\n"                                           \
  41                "       testb %%al,%%al\n"                                 \
  42                "       jz 1f\n"                                           \
  43                "       decl %1\n"                                         \
  44                "       jnz 0b\n"                                          \
  45                "1:     subl %1,%0\n"                                      \
  46                "2:\n"                                                     \
  47                ".section .fixup,\"ax\"\n"                                 \
  48                "3:     movl %5,%0\n"                                      \
  49                "       jmp 2b\n"                                          \
  50                ".previous\n"                                              \
  51                _ASM_EXTABLE(0b,3b)                                        \
  52                : "=d"(res), "=c"(count), "=&a" (__d0), "=&S" (__d1),      \
  53                  "=&D" (__d2)                                             \
  54                : "i"(-EFAULT), "0"(count), "1"(count), "3"(src), "4"(dst) \
  55                : "memory");                                               \
  56} while (0)
  57
  58/**
  59 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
  60 * @dst:   Destination address, in kernel space.  This buffer must be at
  61 *         least @count bytes long.
  62 * @src:   Source address, in user space.
  63 * @count: Maximum number of bytes to copy, including the trailing NUL.
  64 * 
  65 * Copies a NUL-terminated string from userspace to kernel space.
  66 * Caller must check the specified block with access_ok() before calling
  67 * this function.
  68 *
  69 * On success, returns the length of the string (not including the trailing
  70 * NUL).
  71 *
  72 * If access to userspace fails, returns -EFAULT (some data may have been
  73 * copied).
  74 *
  75 * If @count is smaller than the length of the string, copies @count bytes
  76 * and returns @count.
  77 */
  78long
  79__strncpy_from_user(char *dst, const char __user *src, long count)
  80{
  81        long res;
  82        __do_strncpy_from_user(dst, src, count, res);
  83        return res;
  84}
  85EXPORT_SYMBOL(__strncpy_from_user);
  86
  87/**
  88 * strncpy_from_user: - Copy a NUL terminated string from userspace.
  89 * @dst:   Destination address, in kernel space.  This buffer must be at
  90 *         least @count bytes long.
  91 * @src:   Source address, in user space.
  92 * @count: Maximum number of bytes to copy, including the trailing NUL.
  93 * 
  94 * Copies a NUL-terminated string from userspace to kernel space.
  95 *
  96 * On success, returns the length of the string (not including the trailing
  97 * NUL).
  98 *
  99 * If access to userspace fails, returns -EFAULT (some data may have been
 100 * copied).
 101 *
 102 * If @count is smaller than the length of the string, copies @count bytes
 103 * and returns @count.
 104 */
 105long
 106strncpy_from_user(char *dst, const char __user *src, long count)
 107{
 108        long res = -EFAULT;
 109        if (access_ok(VERIFY_READ, src, 1))
 110                __do_strncpy_from_user(dst, src, count, res);
 111        return res;
 112}
 113EXPORT_SYMBOL(strncpy_from_user);
 114
 115/*
 116 * Zero Userspace
 117 */
 118
 119#define __do_clear_user(addr,size)                                      \
 120do {                                                                    \
 121        int __d0;                                                       \
 122        might_sleep();                                                  \
 123        __asm__ __volatile__(                                           \
 124                "0:     rep; stosl\n"                                   \
 125                "       movl %2,%0\n"                                   \
 126                "1:     rep; stosb\n"                                   \
 127                "2:\n"                                                  \
 128                ".section .fixup,\"ax\"\n"                              \
 129                "3:     lea 0(%2,%0,4),%0\n"                            \
 130                "       jmp 2b\n"                                       \
 131                ".previous\n"                                           \
 132                _ASM_EXTABLE(0b,3b)                                     \
 133                _ASM_EXTABLE(1b,2b)                                     \
 134                : "=&c"(size), "=&D" (__d0)                             \
 135                : "r"(size & 3), "0"(size / 4), "1"(addr), "a"(0));     \
 136} while (0)
 137
 138/**
 139 * clear_user: - Zero a block of memory in user space.
 140 * @to:   Destination address, in user space.
 141 * @n:    Number of bytes to zero.
 142 *
 143 * Zero a block of memory in user space.
 144 *
 145 * Returns number of bytes that could not be cleared.
 146 * On success, this will be zero.
 147 */
 148unsigned long
 149clear_user(void __user *to, unsigned long n)
 150{
 151        might_sleep();
 152        if (access_ok(VERIFY_WRITE, to, n))
 153                __do_clear_user(to, n);
 154        return n;
 155}
 156EXPORT_SYMBOL(clear_user);
 157
 158/**
 159 * __clear_user: - Zero a block of memory in user space, with less checking.
 160 * @to:   Destination address, in user space.
 161 * @n:    Number of bytes to zero.
 162 *
 163 * Zero a block of memory in user space.  Caller must check
 164 * the specified block with access_ok() before calling this function.
 165 *
 166 * Returns number of bytes that could not be cleared.
 167 * On success, this will be zero.
 168 */
 169unsigned long
 170__clear_user(void __user *to, unsigned long n)
 171{
 172        __do_clear_user(to, n);
 173        return n;
 174}
 175EXPORT_SYMBOL(__clear_user);
 176
 177/**
 178 * strnlen_user: - Get the size of a string in user space.
 179 * @s: The string to measure.
 180 * @n: The maximum valid length
 181 *
 182 * Get the size of a NUL-terminated string in user space.
 183 *
 184 * Returns the size of the string INCLUDING the terminating NUL.
 185 * On exception, returns 0.
 186 * If the string is too long, returns a value greater than @n.
 187 */
 188long strnlen_user(const char __user *s, long n)
 189{
 190        unsigned long mask = -__addr_ok(s);
 191        unsigned long res, tmp;
 192
 193        might_sleep();
 194
 195        __asm__ __volatile__(
 196                "       testl %0, %0\n"
 197                "       jz 3f\n"
 198                "       andl %0,%%ecx\n"
 199                "0:     repne; scasb\n"
 200                "       setne %%al\n"
 201                "       subl %%ecx,%0\n"
 202                "       addl %0,%%eax\n"
 203                "1:\n"
 204                ".section .fixup,\"ax\"\n"
 205                "2:     xorl %%eax,%%eax\n"
 206                "       jmp 1b\n"
 207                "3:     movb $1,%%al\n"
 208                "       jmp 1b\n"
 209                ".previous\n"
 210                ".section __ex_table,\"a\"\n"
 211                "       .align 4\n"
 212                "       .long 0b,2b\n"
 213                ".previous"
 214                :"=r" (n), "=D" (s), "=a" (res), "=c" (tmp)
 215                :"0" (n), "1" (s), "2" (0), "3" (mask)
 216                :"cc");
 217        return res & mask;
 218}
 219EXPORT_SYMBOL(strnlen_user);
 220
 221#ifdef CONFIG_X86_INTEL_USERCOPY
 222static unsigned long
 223__copy_user_intel(void __user *to, const void *from, unsigned long size)
 224{
 225        int d0, d1;
 226        __asm__ __volatile__(
 227                       "       .align 2,0x90\n"
 228                       "1:     movl 32(%4), %%eax\n"
 229                       "       cmpl $67, %0\n"
 230                       "       jbe 3f\n"
 231                       "2:     movl 64(%4), %%eax\n"
 232                       "       .align 2,0x90\n"
 233                       "3:     movl 0(%4), %%eax\n"
 234                       "4:     movl 4(%4), %%edx\n"
 235                       "5:     movl %%eax, 0(%3)\n"
 236                       "6:     movl %%edx, 4(%3)\n"
 237                       "7:     movl 8(%4), %%eax\n"
 238                       "8:     movl 12(%4),%%edx\n"
 239                       "9:     movl %%eax, 8(%3)\n"
 240                       "10:    movl %%edx, 12(%3)\n"
 241                       "11:    movl 16(%4), %%eax\n"
 242                       "12:    movl 20(%4), %%edx\n"
 243                       "13:    movl %%eax, 16(%3)\n"
 244                       "14:    movl %%edx, 20(%3)\n"
 245                       "15:    movl 24(%4), %%eax\n"
 246                       "16:    movl 28(%4), %%edx\n"
 247                       "17:    movl %%eax, 24(%3)\n"
 248                       "18:    movl %%edx, 28(%3)\n"
 249                       "19:    movl 32(%4), %%eax\n"
 250                       "20:    movl 36(%4), %%edx\n"
 251                       "21:    movl %%eax, 32(%3)\n"
 252                       "22:    movl %%edx, 36(%3)\n"
 253                       "23:    movl 40(%4), %%eax\n"
 254                       "24:    movl 44(%4), %%edx\n"
 255                       "25:    movl %%eax, 40(%3)\n"
 256                       "26:    movl %%edx, 44(%3)\n"
 257                       "27:    movl 48(%4), %%eax\n"
 258                       "28:    movl 52(%4), %%edx\n"
 259                       "29:    movl %%eax, 48(%3)\n"
 260                       "30:    movl %%edx, 52(%3)\n"
 261                       "31:    movl 56(%4), %%eax\n"
 262                       "32:    movl 60(%4), %%edx\n"
 263                       "33:    movl %%eax, 56(%3)\n"
 264                       "34:    movl %%edx, 60(%3)\n"
 265                       "       addl $-64, %0\n"
 266                       "       addl $64, %4\n"
 267                       "       addl $64, %3\n"
 268                       "       cmpl $63, %0\n"
 269                       "       ja  1b\n"
 270                       "35:    movl  %0, %%eax\n"
 271                       "       shrl  $2, %0\n"
 272                       "       andl  $3, %%eax\n"
 273                       "       cld\n"
 274                       "99:    rep; movsl\n"
 275                       "36:    movl %%eax, %0\n"
 276                       "37:    rep; movsb\n"
 277                       "100:\n"
 278                       ".section .fixup,\"ax\"\n"
 279                       "101:   lea 0(%%eax,%0,4),%0\n"
 280                       "       jmp 100b\n"
 281                       ".previous\n"
 282                       ".section __ex_table,\"a\"\n"
 283                       "       .align 4\n"
 284                       "       .long 1b,100b\n"
 285                       "       .long 2b,100b\n"
 286                       "       .long 3b,100b\n"
 287                       "       .long 4b,100b\n"
 288                       "       .long 5b,100b\n"
 289                       "       .long 6b,100b\n"
 290                       "       .long 7b,100b\n"
 291                       "       .long 8b,100b\n"
 292                       "       .long 9b,100b\n"
 293                       "       .long 10b,100b\n"
 294                       "       .long 11b,100b\n"
 295                       "       .long 12b,100b\n"
 296                       "       .long 13b,100b\n"
 297                       "       .long 14b,100b\n"
 298                       "       .long 15b,100b\n"
 299                       "       .long 16b,100b\n"
 300                       "       .long 17b,100b\n"
 301                       "       .long 18b,100b\n"
 302                       "       .long 19b,100b\n"
 303                       "       .long 20b,100b\n"
 304                       "       .long 21b,100b\n"
 305                       "       .long 22b,100b\n"
 306                       "       .long 23b,100b\n"
 307                       "       .long 24b,100b\n"
 308                       "       .long 25b,100b\n"
 309                       "       .long 26b,100b\n"
 310                       "       .long 27b,100b\n"
 311                       "       .long 28b,100b\n"
 312                       "       .long 29b,100b\n"
 313                       "       .long 30b,100b\n"
 314                       "       .long 31b,100b\n"
 315                       "       .long 32b,100b\n"
 316                       "       .long 33b,100b\n"
 317                       "       .long 34b,100b\n"
 318                       "       .long 35b,100b\n"
 319                       "       .long 36b,100b\n"
 320                       "       .long 37b,100b\n"
 321                       "       .long 99b,101b\n"
 322                       ".previous"
 323                       : "=&c"(size), "=&D" (d0), "=&S" (d1)
 324                       :  "1"(to), "2"(from), "0"(size)
 325                       : "eax", "edx", "memory");
 326        return size;
 327}
 328
 329static unsigned long
 330__copy_user_zeroing_intel(void *to, const void __user *from, unsigned long size)
 331{
 332        int d0, d1;
 333        __asm__ __volatile__(
 334                       "        .align 2,0x90\n"
 335                       "0:      movl 32(%4), %%eax\n"
 336                       "        cmpl $67, %0\n"      
 337                       "        jbe 2f\n"            
 338                       "1:      movl 64(%4), %%eax\n"
 339                       "        .align 2,0x90\n"     
 340                       "2:      movl 0(%4), %%eax\n" 
 341                       "21:     movl 4(%4), %%edx\n" 
 342                       "        movl %%eax, 0(%3)\n" 
 343                       "        movl %%edx, 4(%3)\n" 
 344                       "3:      movl 8(%4), %%eax\n" 
 345                       "31:     movl 12(%4),%%edx\n" 
 346                       "        movl %%eax, 8(%3)\n" 
 347                       "        movl %%edx, 12(%3)\n"
 348                       "4:      movl 16(%4), %%eax\n"
 349                       "41:     movl 20(%4), %%edx\n"
 350                       "        movl %%eax, 16(%3)\n"
 351                       "        movl %%edx, 20(%3)\n"
 352                       "10:     movl 24(%4), %%eax\n"
 353                       "51:     movl 28(%4), %%edx\n"
 354                       "        movl %%eax, 24(%3)\n"
 355                       "        movl %%edx, 28(%3)\n"
 356                       "11:     movl 32(%4), %%eax\n"
 357                       "61:     movl 36(%4), %%edx\n"
 358                       "        movl %%eax, 32(%3)\n"
 359                       "        movl %%edx, 36(%3)\n"
 360                       "12:     movl 40(%4), %%eax\n"
 361                       "71:     movl 44(%4), %%edx\n"
 362                       "        movl %%eax, 40(%3)\n"
 363                       "        movl %%edx, 44(%3)\n"
 364                       "13:     movl 48(%4), %%eax\n"
 365                       "81:     movl 52(%4), %%edx\n"
 366                       "        movl %%eax, 48(%3)\n"
 367                       "        movl %%edx, 52(%3)\n"
 368                       "14:     movl 56(%4), %%eax\n"
 369                       "91:     movl 60(%4), %%edx\n"
 370                       "        movl %%eax, 56(%3)\n"
 371                       "        movl %%edx, 60(%3)\n"
 372                       "        addl $-64, %0\n"     
 373                       "        addl $64, %4\n"      
 374                       "        addl $64, %3\n"      
 375                       "        cmpl $63, %0\n"      
 376                       "        ja  0b\n"            
 377                       "5:      movl  %0, %%eax\n"   
 378                       "        shrl  $2, %0\n"      
 379                       "        andl $3, %%eax\n"    
 380                       "        cld\n"               
 381                       "6:      rep; movsl\n"   
 382                       "        movl %%eax,%0\n"
 383                       "7:      rep; movsb\n"   
 384                       "8:\n"                   
 385                       ".section .fixup,\"ax\"\n"
 386                       "9:      lea 0(%%eax,%0,4),%0\n" 
 387                       "16:     pushl %0\n"     
 388                       "        pushl %%eax\n"  
 389                       "        xorl %%eax,%%eax\n"
 390                       "        rep; stosb\n"   
 391                       "        popl %%eax\n"   
 392                       "        popl %0\n"      
 393                       "        jmp 8b\n"       
 394                       ".previous\n"            
 395                       ".section __ex_table,\"a\"\n"
 396                       "        .align 4\n"        
 397                       "        .long 0b,16b\n"  
 398                       "        .long 1b,16b\n"
 399                       "        .long 2b,16b\n"
 400                       "        .long 21b,16b\n"
 401                       "        .long 3b,16b\n" 
 402                       "        .long 31b,16b\n"
 403                       "        .long 4b,16b\n" 
 404                       "        .long 41b,16b\n"
 405                       "        .long 10b,16b\n"
 406                       "        .long 51b,16b\n"
 407                       "        .long 11b,16b\n"
 408                       "        .long 61b,16b\n"
 409                       "        .long 12b,16b\n"
 410                       "        .long 71b,16b\n"
 411                       "        .long 13b,16b\n"
 412                       "        .long 81b,16b\n"
 413                       "        .long 14b,16b\n"
 414                       "        .long 91b,16b\n"
 415                       "        .long 6b,9b\n"  
 416                       "        .long 7b,16b\n" 
 417                       ".previous"              
 418                       : "=&c"(size), "=&D" (d0), "=&S" (d1)
 419                       :  "1"(to), "2"(from), "0"(size)
 420                       : "eax", "edx", "memory");
 421        return size;
 422}
 423
 424/*
 425 * Non Temporal Hint version of __copy_user_zeroing_intel.  It is cache aware.
 426 * hyoshiok@miraclelinux.com
 427 */
 428
 429static unsigned long __copy_user_zeroing_intel_nocache(void *to,
 430                                const void __user *from, unsigned long size)
 431{
 432        int d0, d1;
 433
 434        __asm__ __volatile__(
 435               "        .align 2,0x90\n"
 436               "0:      movl 32(%4), %%eax\n"
 437               "        cmpl $67, %0\n"
 438               "        jbe 2f\n"
 439               "1:      movl 64(%4), %%eax\n"
 440               "        .align 2,0x90\n"
 441               "2:      movl 0(%4), %%eax\n"
 442               "21:     movl 4(%4), %%edx\n"
 443               "        movnti %%eax, 0(%3)\n"
 444               "        movnti %%edx, 4(%3)\n"
 445               "3:      movl 8(%4), %%eax\n"
 446               "31:     movl 12(%4),%%edx\n"
 447               "        movnti %%eax, 8(%3)\n"
 448               "        movnti %%edx, 12(%3)\n"
 449               "4:      movl 16(%4), %%eax\n"
 450               "41:     movl 20(%4), %%edx\n"
 451               "        movnti %%eax, 16(%3)\n"
 452               "        movnti %%edx, 20(%3)\n"
 453               "10:     movl 24(%4), %%eax\n"
 454               "51:     movl 28(%4), %%edx\n"
 455               "        movnti %%eax, 24(%3)\n"
 456               "        movnti %%edx, 28(%3)\n"
 457               "11:     movl 32(%4), %%eax\n"
 458               "61:     movl 36(%4), %%edx\n"
 459               "        movnti %%eax, 32(%3)\n"
 460               "        movnti %%edx, 36(%3)\n"
 461               "12:     movl 40(%4), %%eax\n"
 462               "71:     movl 44(%4), %%edx\n"
 463               "        movnti %%eax, 40(%3)\n"
 464               "        movnti %%edx, 44(%3)\n"
 465               "13:     movl 48(%4), %%eax\n"
 466               "81:     movl 52(%4), %%edx\n"
 467               "        movnti %%eax, 48(%3)\n"
 468               "        movnti %%edx, 52(%3)\n"
 469               "14:     movl 56(%4), %%eax\n"
 470               "91:     movl 60(%4), %%edx\n"
 471               "        movnti %%eax, 56(%3)\n"
 472               "        movnti %%edx, 60(%3)\n"
 473               "        addl $-64, %0\n"
 474               "        addl $64, %4\n"
 475               "        addl $64, %3\n"
 476               "        cmpl $63, %0\n"
 477               "        ja  0b\n"
 478               "        sfence \n"
 479               "5:      movl  %0, %%eax\n"
 480               "        shrl  $2, %0\n"
 481               "        andl $3, %%eax\n"
 482               "        cld\n"
 483               "6:      rep; movsl\n"
 484               "        movl %%eax,%0\n"
 485               "7:      rep; movsb\n"
 486               "8:\n"
 487               ".section .fixup,\"ax\"\n"
 488               "9:      lea 0(%%eax,%0,4),%0\n"
 489               "16:     pushl %0\n"
 490               "        pushl %%eax\n"
 491               "        xorl %%eax,%%eax\n"
 492               "        rep; stosb\n"
 493               "        popl %%eax\n"
 494               "        popl %0\n"
 495               "        jmp 8b\n"
 496               ".previous\n"
 497               ".section __ex_table,\"a\"\n"
 498               "        .align 4\n"
 499               "        .long 0b,16b\n"
 500               "        .long 1b,16b\n"
 501               "        .long 2b,16b\n"
 502               "        .long 21b,16b\n"
 503               "        .long 3b,16b\n"
 504               "        .long 31b,16b\n"
 505               "        .long 4b,16b\n"
 506               "        .long 41b,16b\n"
 507               "        .long 10b,16b\n"
 508               "        .long 51b,16b\n"
 509               "        .long 11b,16b\n"
 510               "        .long 61b,16b\n"
 511               "        .long 12b,16b\n"
 512               "        .long 71b,16b\n"
 513               "        .long 13b,16b\n"
 514               "        .long 81b,16b\n"
 515               "        .long 14b,16b\n"
 516               "        .long 91b,16b\n"
 517               "        .long 6b,9b\n"
 518               "        .long 7b,16b\n"
 519               ".previous"
 520               : "=&c"(size), "=&D" (d0), "=&S" (d1)
 521               :  "1"(to), "2"(from), "0"(size)
 522               : "eax", "edx", "memory");
 523        return size;
 524}
 525
 526static unsigned long __copy_user_intel_nocache(void *to,
 527                                const void __user *from, unsigned long size)
 528{
 529        int d0, d1;
 530
 531        __asm__ __volatile__(
 532               "        .align 2,0x90\n"
 533               "0:      movl 32(%4), %%eax\n"
 534               "        cmpl $67, %0\n"
 535               "        jbe 2f\n"
 536               "1:      movl 64(%4), %%eax\n"
 537               "        .align 2,0x90\n"
 538               "2:      movl 0(%4), %%eax\n"
 539               "21:     movl 4(%4), %%edx\n"
 540               "        movnti %%eax, 0(%3)\n"
 541               "        movnti %%edx, 4(%3)\n"
 542               "3:      movl 8(%4), %%eax\n"
 543               "31:     movl 12(%4),%%edx\n"
 544               "        movnti %%eax, 8(%3)\n"
 545               "        movnti %%edx, 12(%3)\n"
 546               "4:      movl 16(%4), %%eax\n"
 547               "41:     movl 20(%4), %%edx\n"
 548               "        movnti %%eax, 16(%3)\n"
 549               "        movnti %%edx, 20(%3)\n"
 550               "10:     movl 24(%4), %%eax\n"
 551               "51:     movl 28(%4), %%edx\n"
 552               "        movnti %%eax, 24(%3)\n"
 553               "        movnti %%edx, 28(%3)\n"
 554               "11:     movl 32(%4), %%eax\n"
 555               "61:     movl 36(%4), %%edx\n"
 556               "        movnti %%eax, 32(%3)\n"
 557               "        movnti %%edx, 36(%3)\n"
 558               "12:     movl 40(%4), %%eax\n"
 559               "71:     movl 44(%4), %%edx\n"
 560               "        movnti %%eax, 40(%3)\n"
 561               "        movnti %%edx, 44(%3)\n"
 562               "13:     movl 48(%4), %%eax\n"
 563               "81:     movl 52(%4), %%edx\n"
 564               "        movnti %%eax, 48(%3)\n"
 565               "        movnti %%edx, 52(%3)\n"
 566               "14:     movl 56(%4), %%eax\n"
 567               "91:     movl 60(%4), %%edx\n"
 568               "        movnti %%eax, 56(%3)\n"
 569               "        movnti %%edx, 60(%3)\n"
 570               "        addl $-64, %0\n"
 571               "        addl $64, %4\n"
 572               "        addl $64, %3\n"
 573               "        cmpl $63, %0\n"
 574               "        ja  0b\n"
 575               "        sfence \n"
 576               "5:      movl  %0, %%eax\n"
 577               "        shrl  $2, %0\n"
 578               "        andl $3, %%eax\n"
 579               "        cld\n"
 580               "6:      rep; movsl\n"
 581               "        movl %%eax,%0\n"
 582               "7:      rep; movsb\n"
 583               "8:\n"
 584               ".section .fixup,\"ax\"\n"
 585               "9:      lea 0(%%eax,%0,4),%0\n"
 586               "16:     jmp 8b\n"
 587               ".previous\n"
 588               ".section __ex_table,\"a\"\n"
 589               "        .align 4\n"
 590               "        .long 0b,16b\n"
 591               "        .long 1b,16b\n"
 592               "        .long 2b,16b\n"
 593               "        .long 21b,16b\n"
 594               "        .long 3b,16b\n"
 595               "        .long 31b,16b\n"
 596               "        .long 4b,16b\n"
 597               "        .long 41b,16b\n"
 598               "        .long 10b,16b\n"
 599               "        .long 51b,16b\n"
 600               "        .long 11b,16b\n"
 601               "        .long 61b,16b\n"
 602               "        .long 12b,16b\n"
 603               "        .long 71b,16b\n"
 604               "        .long 13b,16b\n"
 605               "        .long 81b,16b\n"
 606               "        .long 14b,16b\n"
 607               "        .long 91b,16b\n"
 608               "        .long 6b,9b\n"
 609               "        .long 7b,16b\n"
 610               ".previous"
 611               : "=&c"(size), "=&D" (d0), "=&S" (d1)
 612               :  "1"(to), "2"(from), "0"(size)
 613               : "eax", "edx", "memory");
 614        return size;
 615}
 616
 617#else
 618
 619/*
 620 * Leave these declared but undefined.  They should not be any references to
 621 * them
 622 */
 623unsigned long __copy_user_zeroing_intel(void *to, const void __user *from,
 624                                        unsigned long size);
 625unsigned long __copy_user_intel(void __user *to, const void *from,
 626                                        unsigned long size);
 627unsigned long __copy_user_zeroing_intel_nocache(void *to,
 628                                const void __user *from, unsigned long size);
 629#endif /* CONFIG_X86_INTEL_USERCOPY */
 630
 631/* Generic arbitrary sized copy.  */
 632#define __copy_user(to,from,size)                                       \
 633do {                                                                    \
 634        int __d0, __d1, __d2;                                           \
 635        __asm__ __volatile__(                                           \
 636                "       cmp  $7,%0\n"                                   \
 637                "       jbe  1f\n"                                      \
 638                "       movl %1,%0\n"                                   \
 639                "       negl %0\n"                                      \
 640                "       andl $7,%0\n"                                   \
 641                "       subl %0,%3\n"                                   \
 642                "4:     rep; movsb\n"                                   \
 643                "       movl %3,%0\n"                                   \
 644                "       shrl $2,%0\n"                                   \
 645                "       andl $3,%3\n"                                   \
 646                "       .align 2,0x90\n"                                \
 647                "0:     rep; movsl\n"                                   \
 648                "       movl %3,%0\n"                                   \
 649                "1:     rep; movsb\n"                                   \
 650                "2:\n"                                                  \
 651                ".section .fixup,\"ax\"\n"                              \
 652                "5:     addl %3,%0\n"                                   \
 653                "       jmp 2b\n"                                       \
 654                "3:     lea 0(%3,%0,4),%0\n"                            \
 655                "       jmp 2b\n"                                       \
 656                ".previous\n"                                           \
 657                ".section __ex_table,\"a\"\n"                           \
 658                "       .align 4\n"                                     \
 659                "       .long 4b,5b\n"                                  \
 660                "       .long 0b,3b\n"                                  \
 661                "       .long 1b,2b\n"                                  \
 662                ".previous"                                             \
 663                : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2)   \
 664                : "3"(size), "0"(size), "1"(to), "2"(from)              \
 665                : "memory");                                            \
 666} while (0)
 667
 668#define __copy_user_zeroing(to,from,size)                               \
 669do {                                                                    \
 670        int __d0, __d1, __d2;                                           \
 671        __asm__ __volatile__(                                           \
 672                "       cmp  $7,%0\n"                                   \
 673                "       jbe  1f\n"                                      \
 674                "       movl %1,%0\n"                                   \
 675                "       negl %0\n"                                      \
 676                "       andl $7,%0\n"                                   \
 677                "       subl %0,%3\n"                                   \
 678                "4:     rep; movsb\n"                                   \
 679                "       movl %3,%0\n"                                   \
 680                "       shrl $2,%0\n"                                   \
 681                "       andl $3,%3\n"                                   \
 682                "       .align 2,0x90\n"                                \
 683                "0:     rep; movsl\n"                                   \
 684                "       movl %3,%0\n"                                   \
 685                "1:     rep; movsb\n"                                   \
 686                "2:\n"                                                  \
 687                ".section .fixup,\"ax\"\n"                              \
 688                "5:     addl %3,%0\n"                                   \
 689                "       jmp 6f\n"                                       \
 690                "3:     lea 0(%3,%0,4),%0\n"                            \
 691                "6:     pushl %0\n"                                     \
 692                "       pushl %%eax\n"                                  \
 693                "       xorl %%eax,%%eax\n"                             \
 694                "       rep; stosb\n"                                   \
 695                "       popl %%eax\n"                                   \
 696                "       popl %0\n"                                      \
 697                "       jmp 2b\n"                                       \
 698                ".previous\n"                                           \
 699                ".section __ex_table,\"a\"\n"                           \
 700                "       .align 4\n"                                     \
 701                "       .long 4b,5b\n"                                  \
 702                "       .long 0b,3b\n"                                  \
 703                "       .long 1b,6b\n"                                  \
 704                ".previous"                                             \
 705                : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2)   \
 706                : "3"(size), "0"(size), "1"(to), "2"(from)              \
 707                : "memory");                                            \
 708} while (0)
 709
 710unsigned long __copy_to_user_ll(void __user *to, const void *from,
 711                                unsigned long n)
 712{
 713#ifndef CONFIG_X86_WP_WORKS_OK
 714        if (unlikely(boot_cpu_data.wp_works_ok == 0) &&
 715                        ((unsigned long )to) < TASK_SIZE) {
 716                /*
 717                 * When we are in an atomic section (see
 718                 * mm/filemap.c:file_read_actor), return the full
 719                 * length to take the slow path.
 720                 */
 721                if (in_atomic())
 722                        return n;
 723
 724                /* 
 725                 * CPU does not honor the WP bit when writing
 726                 * from supervisory mode, and due to preemption or SMP,
 727                 * the page tables can change at any time.
 728                 * Do it manually.      Manfred <manfred@colorfullife.com>
 729                 */
 730                while (n) {
 731                        unsigned long offset = ((unsigned long)to)%PAGE_SIZE;
 732                        unsigned long len = PAGE_SIZE - offset;
 733                        int retval;
 734                        struct page *pg;
 735                        void *maddr;
 736                        
 737                        if (len > n)
 738                                len = n;
 739
 740survive:
 741                        down_read(&current->mm->mmap_sem);
 742                        retval = get_user_pages(current, current->mm,
 743                                        (unsigned long )to, 1, 1, 0, &pg, NULL);
 744
 745                        if (retval == -ENOMEM && is_global_init(current)) {
 746                                up_read(&current->mm->mmap_sem);
 747                                congestion_wait(WRITE, HZ/50);
 748                                goto survive;
 749                        }
 750
 751                        if (retval != 1) {
 752                                up_read(&current->mm->mmap_sem);
 753                                break;
 754                        }
 755
 756                        maddr = kmap_atomic(pg, KM_USER0);
 757                        memcpy(maddr + offset, from, len);
 758                        kunmap_atomic(maddr, KM_USER0);
 759                        set_page_dirty_lock(pg);
 760                        put_page(pg);
 761                        up_read(&current->mm->mmap_sem);
 762
 763                        from += len;
 764                        to += len;
 765                        n -= len;
 766                }
 767                return n;
 768        }
 769#endif
 770        if (movsl_is_ok(to, from, n))
 771                __copy_user(to, from, n);
 772        else
 773                n = __copy_user_intel(to, from, n);
 774        return n;
 775}
 776EXPORT_SYMBOL(__copy_to_user_ll);
 777
 778unsigned long __copy_from_user_ll(void *to, const void __user *from,
 779                                        unsigned long n)
 780{
 781        if (movsl_is_ok(to, from, n))
 782                __copy_user_zeroing(to, from, n);
 783        else
 784                n = __copy_user_zeroing_intel(to, from, n);
 785        return n;
 786}
 787EXPORT_SYMBOL(__copy_from_user_ll);
 788
 789unsigned long __copy_from_user_ll_nozero(void *to, const void __user *from,
 790                                         unsigned long n)
 791{
 792        if (movsl_is_ok(to, from, n))
 793                __copy_user(to, from, n);
 794        else
 795                n = __copy_user_intel((void __user *)to,
 796                                      (const void *)from, n);
 797        return n;
 798}
 799EXPORT_SYMBOL(__copy_from_user_ll_nozero);
 800
 801unsigned long __copy_from_user_ll_nocache(void *to, const void __user *from,
 802                                        unsigned long n)
 803{
 804#ifdef CONFIG_X86_INTEL_USERCOPY
 805        if ( n > 64 && cpu_has_xmm2)
 806                n = __copy_user_zeroing_intel_nocache(to, from, n);
 807        else
 808                __copy_user_zeroing(to, from, n);
 809#else
 810        __copy_user_zeroing(to, from, n);
 811#endif
 812        return n;
 813}
 814EXPORT_SYMBOL(__copy_from_user_ll_nocache);
 815
 816unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from,
 817                                        unsigned long n)
 818{
 819#ifdef CONFIG_X86_INTEL_USERCOPY
 820        if ( n > 64 && cpu_has_xmm2)
 821                n = __copy_user_intel_nocache(to, from, n);
 822        else
 823                __copy_user(to, from, n);
 824#else
 825        __copy_user(to, from, n);
 826#endif
 827        return n;
 828}
 829EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero);
 830
 831/**
 832 * copy_to_user: - Copy a block of data into user space.
 833 * @to:   Destination address, in user space.
 834 * @from: Source address, in kernel space.
 835 * @n:    Number of bytes to copy.
 836 *
 837 * Context: User context only.  This function may sleep.
 838 *
 839 * Copy data from kernel space to user space.
 840 *
 841 * Returns number of bytes that could not be copied.
 842 * On success, this will be zero.
 843 */
 844unsigned long
 845copy_to_user(void __user *to, const void *from, unsigned long n)
 846{
 847        if (access_ok(VERIFY_WRITE, to, n))
 848                n = __copy_to_user(to, from, n);
 849        return n;
 850}
 851EXPORT_SYMBOL(copy_to_user);
 852
 853/**
 854 * copy_from_user: - Copy a block of data from user space.
 855 * @to:   Destination address, in kernel space.
 856 * @from: Source address, in user space.
 857 * @n:    Number of bytes to copy.
 858 *
 859 * Context: User context only.  This function may sleep.
 860 *
 861 * Copy data from user space to kernel space.
 862 *
 863 * Returns number of bytes that could not be copied.
 864 * On success, this will be zero.
 865 *
 866 * If some data could not be copied, this function will pad the copied
 867 * data to the requested size using zero bytes.
 868 */
 869unsigned long
 870copy_from_user(void *to, const void __user *from, unsigned long n)
 871{
 872        if (access_ok(VERIFY_READ, from, n))
 873                n = __copy_from_user(to, from, n);
 874        else
 875                memset(to, 0, n);
 876        return n;
 877}
 878EXPORT_SYMBOL(copy_from_user);
 879
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