linux/arch/i386/lib/usercopy.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                ".section __ex_table,\"a\"\n"                              \
  52                "       .align 4\n"                                        \
  53                "       .long 0b,3b\n"                                     \
  54                ".previous"                                                \
  55                : "=d"(res), "=c"(count), "=&a" (__d0), "=&S" (__d1),      \
  56                  "=&D" (__d2)                                             \
  57                : "i"(-EFAULT), "0"(count), "1"(count), "3"(src), "4"(dst) \
  58                : "memory");                                               \
  59} while (0)
  60
  61/**
  62 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
  63 * @dst:   Destination address, in kernel space.  This buffer must be at
  64 *         least @count bytes long.
  65 * @src:   Source address, in user space.
  66 * @count: Maximum number of bytes to copy, including the trailing NUL.
  67 * 
  68 * Copies a NUL-terminated string from userspace to kernel space.
  69 * Caller must check the specified block with access_ok() before calling
  70 * this function.
  71 *
  72 * On success, returns the length of the string (not including the trailing
  73 * NUL).
  74 *
  75 * If access to userspace fails, returns -EFAULT (some data may have been
  76 * copied).
  77 *
  78 * If @count is smaller than the length of the string, copies @count bytes
  79 * and returns @count.
  80 */
  81long
  82__strncpy_from_user(char *dst, const char __user *src, long count)
  83{
  84        long res;
  85        __do_strncpy_from_user(dst, src, count, res);
  86        return res;
  87}
  88EXPORT_SYMBOL(__strncpy_from_user);
  89
  90/**
  91 * strncpy_from_user: - Copy a NUL terminated string from userspace.
  92 * @dst:   Destination address, in kernel space.  This buffer must be at
  93 *         least @count bytes long.
  94 * @src:   Source address, in user space.
  95 * @count: Maximum number of bytes to copy, including the trailing NUL.
  96 * 
  97 * Copies a NUL-terminated string from userspace to kernel space.
  98 *
  99 * On success, returns the length of the string (not including the trailing
 100 * NUL).
 101 *
 102 * If access to userspace fails, returns -EFAULT (some data may have been
 103 * copied).
 104 *
 105 * If @count is smaller than the length of the string, copies @count bytes
 106 * and returns @count.
 107 */
 108long
 109strncpy_from_user(char *dst, const char __user *src, long count)
 110{
 111        long res = -EFAULT;
 112        if (access_ok(VERIFY_READ, src, 1))
 113                __do_strncpy_from_user(dst, src, count, res);
 114        return res;
 115}
 116EXPORT_SYMBOL(strncpy_from_user);
 117
 118/*
 119 * Zero Userspace
 120 */
 121
 122#define __do_clear_user(addr,size)                                      \
 123do {                                                                    \
 124        int __d0;                                                       \
 125        might_sleep();                                                  \
 126        __asm__ __volatile__(                                           \
 127                "0:     rep; stosl\n"                                   \
 128                "       movl %2,%0\n"                                   \
 129                "1:     rep; stosb\n"                                   \
 130                "2:\n"                                                  \
 131                ".section .fixup,\"ax\"\n"                              \
 132                "3:     lea 0(%2,%0,4),%0\n"                            \
 133                "       jmp 2b\n"                                       \
 134                ".previous\n"                                           \
 135                ".section __ex_table,\"a\"\n"                           \
 136                "       .align 4\n"                                     \
 137                "       .long 0b,3b\n"                                  \
 138                "       .long 1b,2b\n"                                  \
 139                ".previous"                                             \
 140                : "=&c"(size), "=&D" (__d0)                             \
 141                : "r"(size & 3), "0"(size / 4), "1"(addr), "a"(0));     \
 142} while (0)
 143
 144/**
 145 * clear_user: - Zero a block of memory in user space.
 146 * @to:   Destination address, in user space.
 147 * @n:    Number of bytes to zero.
 148 *
 149 * Zero a block of memory in user space.
 150 *
 151 * Returns number of bytes that could not be cleared.
 152 * On success, this will be zero.
 153 */
 154unsigned long
 155clear_user(void __user *to, unsigned long n)
 156{
 157        might_sleep();
 158        if (access_ok(VERIFY_WRITE, to, n))
 159                __do_clear_user(to, n);
 160        return n;
 161}
 162EXPORT_SYMBOL(clear_user);
 163
 164/**
 165 * __clear_user: - Zero a block of memory in user space, with less checking.
 166 * @to:   Destination address, in user space.
 167 * @n:    Number of bytes to zero.
 168 *
 169 * Zero a block of memory in user space.  Caller must check
 170 * the specified block with access_ok() before calling this function.
 171 *
 172 * Returns number of bytes that could not be cleared.
 173 * On success, this will be zero.
 174 */
 175unsigned long
 176__clear_user(void __user *to, unsigned long n)
 177{
 178        __do_clear_user(to, n);
 179        return n;
 180}
 181EXPORT_SYMBOL(__clear_user);
 182
 183/**
 184 * strnlen_user: - Get the size of a string in user space.
 185 * @s: The string to measure.
 186 * @n: The maximum valid length
 187 *
 188 * Get the size of a NUL-terminated string in user space.
 189 *
 190 * Returns the size of the string INCLUDING the terminating NUL.
 191 * On exception, returns 0.
 192 * If the string is too long, returns a value greater than @n.
 193 */
 194long strnlen_user(const char __user *s, long n)
 195{
 196        unsigned long mask = -__addr_ok(s);
 197        unsigned long res, tmp;
 198
 199        might_sleep();
 200
 201        __asm__ __volatile__(
 202                "       testl %0, %0\n"
 203                "       jz 3f\n"
 204                "       andl %0,%%ecx\n"
 205                "0:     repne; scasb\n"
 206                "       setne %%al\n"
 207                "       subl %%ecx,%0\n"
 208                "       addl %0,%%eax\n"
 209                "1:\n"
 210                ".section .fixup,\"ax\"\n"
 211                "2:     xorl %%eax,%%eax\n"
 212                "       jmp 1b\n"
 213                "3:     movb $1,%%al\n"
 214                "       jmp 1b\n"
 215                ".previous\n"
 216                ".section __ex_table,\"a\"\n"
 217                "       .align 4\n"
 218                "       .long 0b,2b\n"
 219                ".previous"
 220                :"=r" (n), "=D" (s), "=a" (res), "=c" (tmp)
 221                :"0" (n), "1" (s), "2" (0), "3" (mask)
 222                :"cc");
 223        return res & mask;
 224}
 225EXPORT_SYMBOL(strnlen_user);
 226
 227#ifdef CONFIG_X86_INTEL_USERCOPY
 228static unsigned long
 229__copy_user_intel(void __user *to, const void *from, unsigned long size)
 230{
 231        int d0, d1;
 232        __asm__ __volatile__(
 233                       "       .align 2,0x90\n"
 234                       "1:     movl 32(%4), %%eax\n"
 235                       "       cmpl $67, %0\n"
 236                       "       jbe 3f\n"
 237                       "2:     movl 64(%4), %%eax\n"
 238                       "       .align 2,0x90\n"
 239                       "3:     movl 0(%4), %%eax\n"
 240                       "4:     movl 4(%4), %%edx\n"
 241                       "5:     movl %%eax, 0(%3)\n"
 242                       "6:     movl %%edx, 4(%3)\n"
 243                       "7:     movl 8(%4), %%eax\n"
 244                       "8:     movl 12(%4),%%edx\n"
 245                       "9:     movl %%eax, 8(%3)\n"
 246                       "10:    movl %%edx, 12(%3)\n"
 247                       "11:    movl 16(%4), %%eax\n"
 248                       "12:    movl 20(%4), %%edx\n"
 249                       "13:    movl %%eax, 16(%3)\n"
 250                       "14:    movl %%edx, 20(%3)\n"
 251                       "15:    movl 24(%4), %%eax\n"
 252                       "16:    movl 28(%4), %%edx\n"
 253                       "17:    movl %%eax, 24(%3)\n"
 254                       "18:    movl %%edx, 28(%3)\n"
 255                       "19:    movl 32(%4), %%eax\n"
 256                       "20:    movl 36(%4), %%edx\n"
 257                       "21:    movl %%eax, 32(%3)\n"
 258                       "22:    movl %%edx, 36(%3)\n"
 259                       "23:    movl 40(%4), %%eax\n"
 260                       "24:    movl 44(%4), %%edx\n"
 261                       "25:    movl %%eax, 40(%3)\n"
 262                       "26:    movl %%edx, 44(%3)\n"
 263                       "27:    movl 48(%4), %%eax\n"
 264                       "28:    movl 52(%4), %%edx\n"
 265                       "29:    movl %%eax, 48(%3)\n"
 266                       "30:    movl %%edx, 52(%3)\n"
 267                       "31:    movl 56(%4), %%eax\n"
 268                       "32:    movl 60(%4), %%edx\n"
 269                       "33:    movl %%eax, 56(%3)\n"
 270                       "34:    movl %%edx, 60(%3)\n"
 271                       "       addl $-64, %0\n"
 272                       "       addl $64, %4\n"
 273                       "       addl $64, %3\n"
 274                       "       cmpl $63, %0\n"
 275                       "       ja  1b\n"
 276                       "35:    movl  %0, %%eax\n"
 277                       "       shrl  $2, %0\n"
 278                       "       andl  $3, %%eax\n"
 279                       "       cld\n"
 280                       "99:    rep; movsl\n"
 281                       "36:    movl %%eax, %0\n"
 282                       "37:    rep; movsb\n"
 283                       "100:\n"
 284                       ".section .fixup,\"ax\"\n"
 285                       "101:   lea 0(%%eax,%0,4),%0\n"
 286                       "       jmp 100b\n"
 287                       ".previous\n"
 288                       ".section __ex_table,\"a\"\n"
 289                       "       .align 4\n"
 290                       "       .long 1b,100b\n"
 291                       "       .long 2b,100b\n"
 292                       "       .long 3b,100b\n"
 293                       "       .long 4b,100b\n"
 294                       "       .long 5b,100b\n"
 295                       "       .long 6b,100b\n"
 296                       "       .long 7b,100b\n"
 297                       "       .long 8b,100b\n"
 298                       "       .long 9b,100b\n"
 299                       "       .long 10b,100b\n"
 300                       "       .long 11b,100b\n"
 301                       "       .long 12b,100b\n"
 302                       "       .long 13b,100b\n"
 303                       "       .long 14b,100b\n"
 304                       "       .long 15b,100b\n"
 305                       "       .long 16b,100b\n"
 306                       "       .long 17b,100b\n"
 307                       "       .long 18b,100b\n"
 308                       "       .long 19b,100b\n"
 309                       "       .long 20b,100b\n"
 310                       "       .long 21b,100b\n"
 311                       "       .long 22b,100b\n"
 312                       "       .long 23b,100b\n"
 313                       "       .long 24b,100b\n"
 314                       "       .long 25b,100b\n"
 315                       "       .long 26b,100b\n"
 316                       "       .long 27b,100b\n"
 317                       "       .long 28b,100b\n"
 318                       "       .long 29b,100b\n"
 319                       "       .long 30b,100b\n"
 320                       "       .long 31b,100b\n"
 321                       "       .long 32b,100b\n"
 322                       "       .long 33b,100b\n"
 323                       "       .long 34b,100b\n"
 324                       "       .long 35b,100b\n"
 325                       "       .long 36b,100b\n"
 326                       "       .long 37b,100b\n"
 327                       "       .long 99b,101b\n"
 328                       ".previous"
 329                       : "=&c"(size), "=&D" (d0), "=&S" (d1)
 330                       :  "1"(to), "2"(from), "0"(size)
 331                       : "eax", "edx", "memory");
 332        return size;
 333}
 334
 335static unsigned long
 336__copy_user_zeroing_intel(void *to, const void __user *from, unsigned long size)
 337{
 338        int d0, d1;
 339        __asm__ __volatile__(
 340                       "        .align 2,0x90\n"
 341                       "0:      movl 32(%4), %%eax\n"
 342                       "        cmpl $67, %0\n"      
 343                       "        jbe 2f\n"            
 344                       "1:      movl 64(%4), %%eax\n"
 345                       "        .align 2,0x90\n"     
 346                       "2:      movl 0(%4), %%eax\n" 
 347                       "21:     movl 4(%4), %%edx\n" 
 348                       "        movl %%eax, 0(%3)\n" 
 349                       "        movl %%edx, 4(%3)\n" 
 350                       "3:      movl 8(%4), %%eax\n" 
 351                       "31:     movl 12(%4),%%edx\n" 
 352                       "        movl %%eax, 8(%3)\n" 
 353                       "        movl %%edx, 12(%3)\n"
 354                       "4:      movl 16(%4), %%eax\n"
 355                       "41:     movl 20(%4), %%edx\n"
 356                       "        movl %%eax, 16(%3)\n"
 357                       "        movl %%edx, 20(%3)\n"
 358                       "10:     movl 24(%4), %%eax\n"
 359                       "51:     movl 28(%4), %%edx\n"
 360                       "        movl %%eax, 24(%3)\n"
 361                       "        movl %%edx, 28(%3)\n"
 362                       "11:     movl 32(%4), %%eax\n"
 363                       "61:     movl 36(%4), %%edx\n"
 364                       "        movl %%eax, 32(%3)\n"
 365                       "        movl %%edx, 36(%3)\n"
 366                       "12:     movl 40(%4), %%eax\n"
 367                       "71:     movl 44(%4), %%edx\n"
 368                       "        movl %%eax, 40(%3)\n"
 369                       "        movl %%edx, 44(%3)\n"
 370                       "13:     movl 48(%4), %%eax\n"
 371                       "81:     movl 52(%4), %%edx\n"
 372                       "        movl %%eax, 48(%3)\n"
 373                       "        movl %%edx, 52(%3)\n"
 374                       "14:     movl 56(%4), %%eax\n"
 375                       "91:     movl 60(%4), %%edx\n"
 376                       "        movl %%eax, 56(%3)\n"
 377                       "        movl %%edx, 60(%3)\n"
 378                       "        addl $-64, %0\n"     
 379                       "        addl $64, %4\n"      
 380                       "        addl $64, %3\n"      
 381                       "        cmpl $63, %0\n"      
 382                       "        ja  0b\n"            
 383                       "5:      movl  %0, %%eax\n"   
 384                       "        shrl  $2, %0\n"      
 385                       "        andl $3, %%eax\n"    
 386                       "        cld\n"               
 387                       "6:      rep; movsl\n"   
 388                       "        movl %%eax,%0\n"
 389                       "7:      rep; movsb\n"   
 390                       "8:\n"                   
 391                       ".section .fixup,\"ax\"\n"
 392                       "9:      lea 0(%%eax,%0,4),%0\n" 
 393                       "16:     pushl %0\n"     
 394                       "        pushl %%eax\n"  
 395                       "        xorl %%eax,%%eax\n"
 396                       "        rep; stosb\n"   
 397                       "        popl %%eax\n"   
 398                       "        popl %0\n"      
 399                       "        jmp 8b\n"       
 400                       ".previous\n"            
 401                       ".section __ex_table,\"a\"\n"
 402                       "        .align 4\n"        
 403                       "        .long 0b,16b\n"  
 404                       "        .long 1b,16b\n"
 405                       "        .long 2b,16b\n"
 406                       "        .long 21b,16b\n"
 407                       "        .long 3b,16b\n" 
 408                       "        .long 31b,16b\n"
 409                       "        .long 4b,16b\n" 
 410                       "        .long 41b,16b\n"
 411                       "        .long 10b,16b\n"
 412                       "        .long 51b,16b\n"
 413                       "        .long 11b,16b\n"
 414                       "        .long 61b,16b\n"
 415                       "        .long 12b,16b\n"
 416                       "        .long 71b,16b\n"
 417                       "        .long 13b,16b\n"
 418                       "        .long 81b,16b\n"
 419                       "        .long 14b,16b\n"
 420                       "        .long 91b,16b\n"
 421                       "        .long 6b,9b\n"  
 422                       "        .long 7b,16b\n" 
 423                       ".previous"              
 424                       : "=&c"(size), "=&D" (d0), "=&S" (d1)
 425                       :  "1"(to), "2"(from), "0"(size)
 426                       : "eax", "edx", "memory");
 427        return size;
 428}
 429
 430/*
 431 * Non Temporal Hint version of __copy_user_zeroing_intel.  It is cache aware.
 432 * hyoshiok@miraclelinux.com
 433 */
 434
 435static unsigned long __copy_user_zeroing_intel_nocache(void *to,
 436                                const void __user *from, unsigned long size)
 437{
 438        int d0, d1;
 439
 440        __asm__ __volatile__(
 441               "        .align 2,0x90\n"
 442               "0:      movl 32(%4), %%eax\n"
 443               "        cmpl $67, %0\n"
 444               "        jbe 2f\n"
 445               "1:      movl 64(%4), %%eax\n"
 446               "        .align 2,0x90\n"
 447               "2:      movl 0(%4), %%eax\n"
 448               "21:     movl 4(%4), %%edx\n"
 449               "        movnti %%eax, 0(%3)\n"
 450               "        movnti %%edx, 4(%3)\n"
 451               "3:      movl 8(%4), %%eax\n"
 452               "31:     movl 12(%4),%%edx\n"
 453               "        movnti %%eax, 8(%3)\n"
 454               "        movnti %%edx, 12(%3)\n"
 455               "4:      movl 16(%4), %%eax\n"
 456               "41:     movl 20(%4), %%edx\n"
 457               "        movnti %%eax, 16(%3)\n"
 458               "        movnti %%edx, 20(%3)\n"
 459               "10:     movl 24(%4), %%eax\n"
 460               "51:     movl 28(%4), %%edx\n"
 461               "        movnti %%eax, 24(%3)\n"
 462               "        movnti %%edx, 28(%3)\n"
 463               "11:     movl 32(%4), %%eax\n"
 464               "61:     movl 36(%4), %%edx\n"
 465               "        movnti %%eax, 32(%3)\n"
 466               "        movnti %%edx, 36(%3)\n"
 467               "12:     movl 40(%4), %%eax\n"
 468               "71:     movl 44(%4), %%edx\n"
 469               "        movnti %%eax, 40(%3)\n"
 470               "        movnti %%edx, 44(%3)\n"
 471               "13:     movl 48(%4), %%eax\n"
 472               "81:     movl 52(%4), %%edx\n"
 473               "        movnti %%eax, 48(%3)\n"
 474               "        movnti %%edx, 52(%3)\n"
 475               "14:     movl 56(%4), %%eax\n"
 476               "91:     movl 60(%4), %%edx\n"
 477               "        movnti %%eax, 56(%3)\n"
 478               "        movnti %%edx, 60(%3)\n"
 479               "        addl $-64, %0\n"
 480               "        addl $64, %4\n"
 481               "        addl $64, %3\n"
 482               "        cmpl $63, %0\n"
 483               "        ja  0b\n"
 484               "        sfence \n"
 485               "5:      movl  %0, %%eax\n"
 486               "        shrl  $2, %0\n"
 487               "        andl $3, %%eax\n"
 488               "        cld\n"
 489               "6:      rep; movsl\n"
 490               "        movl %%eax,%0\n"
 491               "7:      rep; movsb\n"
 492               "8:\n"
 493               ".section .fixup,\"ax\"\n"
 494               "9:      lea 0(%%eax,%0,4),%0\n"
 495               "16:     pushl %0\n"
 496               "        pushl %%eax\n"
 497               "        xorl %%eax,%%eax\n"
 498               "        rep; stosb\n"
 499               "        popl %%eax\n"
 500               "        popl %0\n"
 501               "        jmp 8b\n"
 502               ".previous\n"
 503               ".section __ex_table,\"a\"\n"
 504               "        .align 4\n"
 505               "        .long 0b,16b\n"
 506               "        .long 1b,16b\n"
 507               "        .long 2b,16b\n"
 508               "        .long 21b,16b\n"
 509               "        .long 3b,16b\n"
 510               "        .long 31b,16b\n"
 511               "        .long 4b,16b\n"
 512               "        .long 41b,16b\n"
 513               "        .long 10b,16b\n"
 514               "        .long 51b,16b\n"
 515               "        .long 11b,16b\n"
 516               "        .long 61b,16b\n"
 517               "        .long 12b,16b\n"
 518               "        .long 71b,16b\n"
 519               "        .long 13b,16b\n"
 520               "        .long 81b,16b\n"
 521               "        .long 14b,16b\n"
 522               "        .long 91b,16b\n"
 523               "        .long 6b,9b\n"
 524               "        .long 7b,16b\n"
 525               ".previous"
 526               : "=&c"(size), "=&D" (d0), "=&S" (d1)
 527               :  "1"(to), "2"(from), "0"(size)
 528               : "eax", "edx", "memory");
 529        return size;
 530}
 531
 532static unsigned long __copy_user_intel_nocache(void *to,
 533                                const void __user *from, unsigned long size)
 534{
 535        int d0, d1;
 536
 537        __asm__ __volatile__(
 538               "        .align 2,0x90\n"
 539               "0:      movl 32(%4), %%eax\n"
 540               "        cmpl $67, %0\n"
 541               "        jbe 2f\n"
 542               "1:      movl 64(%4), %%eax\n"
 543               "        .align 2,0x90\n"
 544               "2:      movl 0(%4), %%eax\n"
 545               "21:     movl 4(%4), %%edx\n"
 546               "        movnti %%eax, 0(%3)\n"
 547               "        movnti %%edx, 4(%3)\n"
 548               "3:      movl 8(%4), %%eax\n"
 549               "31:     movl 12(%4),%%edx\n"
 550               "        movnti %%eax, 8(%3)\n"
 551               "        movnti %%edx, 12(%3)\n"
 552               "4:      movl 16(%4), %%eax\n"
 553               "41:     movl 20(%4), %%edx\n"
 554               "        movnti %%eax, 16(%3)\n"
 555               "        movnti %%edx, 20(%3)\n"
 556               "10:     movl 24(%4), %%eax\n"
 557               "51:     movl 28(%4), %%edx\n"
 558               "        movnti %%eax, 24(%3)\n"
 559               "        movnti %%edx, 28(%3)\n"
 560               "11:     movl 32(%4), %%eax\n"
 561               "61:     movl 36(%4), %%edx\n"
 562               "        movnti %%eax, 32(%3)\n"
 563               "        movnti %%edx, 36(%3)\n"
 564               "12:     movl 40(%4), %%eax\n"
 565               "71:     movl 44(%4), %%edx\n"
 566               "        movnti %%eax, 40(%3)\n"
 567               "        movnti %%edx, 44(%3)\n"
 568               "13:     movl 48(%4), %%eax\n"
 569               "81:     movl 52(%4), %%edx\n"
 570               "        movnti %%eax, 48(%3)\n"
 571               "        movnti %%edx, 52(%3)\n"
 572               "14:     movl 56(%4), %%eax\n"
 573               "91:     movl 60(%4), %%edx\n"
 574               "        movnti %%eax, 56(%3)\n"
 575               "        movnti %%edx, 60(%3)\n"
 576               "        addl $-64, %0\n"
 577               "        addl $64, %4\n"
 578               "        addl $64, %3\n"
 579               "        cmpl $63, %0\n"
 580               "        ja  0b\n"
 581               "        sfence \n"
 582               "5:      movl  %0, %%eax\n"
 583               "        shrl  $2, %0\n"
 584               "        andl $3, %%eax\n"
 585               "        cld\n"
 586               "6:      rep; movsl\n"
 587               "        movl %%eax,%0\n"
 588               "7:      rep; movsb\n"
 589               "8:\n"
 590               ".section .fixup,\"ax\"\n"
 591               "9:      lea 0(%%eax,%0,4),%0\n"
 592               "16:     jmp 8b\n"
 593               ".previous\n"
 594               ".section __ex_table,\"a\"\n"
 595               "        .align 4\n"
 596               "        .long 0b,16b\n"
 597               "        .long 1b,16b\n"
 598               "        .long 2b,16b\n"
 599               "        .long 21b,16b\n"
 600               "        .long 3b,16b\n"
 601               "        .long 31b,16b\n"
 602               "        .long 4b,16b\n"
 603               "        .long 41b,16b\n"
 604               "        .long 10b,16b\n"
 605               "        .long 51b,16b\n"
 606               "        .long 11b,16b\n"
 607               "        .long 61b,16b\n"
 608               "        .long 12b,16b\n"
 609               "        .long 71b,16b\n"
 610               "        .long 13b,16b\n"
 611               "        .long 81b,16b\n"
 612               "        .long 14b,16b\n"
 613               "        .long 91b,16b\n"
 614               "        .long 6b,9b\n"
 615               "        .long 7b,16b\n"
 616               ".previous"
 617               : "=&c"(size), "=&D" (d0), "=&S" (d1)
 618               :  "1"(to), "2"(from), "0"(size)
 619               : "eax", "edx", "memory");
 620        return size;
 621}
 622
 623#else
 624
 625/*
 626 * Leave these declared but undefined.  They should not be any references to
 627 * them
 628 */
 629unsigned long __copy_user_zeroing_intel(void *to, const void __user *from,
 630                                        unsigned long size);
 631unsigned long __copy_user_intel(void __user *to, const void *from,
 632                                        unsigned long size);
 633unsigned long __copy_user_zeroing_intel_nocache(void *to,
 634                                const void __user *from, unsigned long size);
 635#endif /* CONFIG_X86_INTEL_USERCOPY */
 636
 637/* Generic arbitrary sized copy.  */
 638#define __copy_user(to,from,size)                                       \
 639do {                                                                    \
 640        int __d0, __d1, __d2;                                           \
 641        __asm__ __volatile__(                                           \
 642                "       cmp  $7,%0\n"                                   \
 643                "       jbe  1f\n"                                      \
 644                "       movl %1,%0\n"                                   \
 645                "       negl %0\n"                                      \
 646                "       andl $7,%0\n"                                   \
 647                "       subl %0,%3\n"                                   \
 648                "4:     rep; movsb\n"                                   \
 649                "       movl %3,%0\n"                                   \
 650                "       shrl $2,%0\n"                                   \
 651                "       andl $3,%3\n"                                   \
 652                "       .align 2,0x90\n"                                \
 653                "0:     rep; movsl\n"                                   \
 654                "       movl %3,%0\n"                                   \
 655                "1:     rep; movsb\n"                                   \
 656                "2:\n"                                                  \
 657                ".section .fixup,\"ax\"\n"                              \
 658                "5:     addl %3,%0\n"                                   \
 659                "       jmp 2b\n"                                       \
 660                "3:     lea 0(%3,%0,4),%0\n"                            \
 661                "       jmp 2b\n"                                       \
 662                ".previous\n"                                           \
 663                ".section __ex_table,\"a\"\n"                           \
 664                "       .align 4\n"                                     \
 665                "       .long 4b,5b\n"                                  \
 666                "       .long 0b,3b\n"                                  \
 667                "       .long 1b,2b\n"                                  \
 668                ".previous"                                             \
 669                : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2)   \
 670                : "3"(size), "0"(size), "1"(to), "2"(from)              \
 671                : "memory");                                            \
 672} while (0)
 673
 674#define __copy_user_zeroing(to,from,size)                               \
 675do {                                                                    \
 676        int __d0, __d1, __d2;                                           \
 677        __asm__ __volatile__(                                           \
 678                "       cmp  $7,%0\n"                                   \
 679                "       jbe  1f\n"                                      \
 680                "       movl %1,%0\n"                                   \
 681                "       negl %0\n"                                      \
 682                "       andl $7,%0\n"                                   \
 683                "       subl %0,%3\n"                                   \
 684                "4:     rep; movsb\n"                                   \
 685                "       movl %3,%0\n"                                   \
 686                "       shrl $2,%0\n"                                   \
 687                "       andl $3,%3\n"                                   \
 688                "       .align 2,0x90\n"                                \
 689                "0:     rep; movsl\n"                                   \
 690                "       movl %3,%0\n"                                   \
 691                "1:     rep; movsb\n"                                   \
 692                "2:\n"                                                  \
 693                ".section .fixup,\"ax\"\n"                              \
 694                "5:     addl %3,%0\n"                                   \
 695                "       jmp 6f\n"                                       \
 696                "3:     lea 0(%3,%0,4),%0\n"                            \
 697                "6:     pushl %0\n"                                     \
 698                "       pushl %%eax\n"                                  \
 699                "       xorl %%eax,%%eax\n"                             \
 700                "       rep; stosb\n"                                   \
 701                "       popl %%eax\n"                                   \
 702                "       popl %0\n"                                      \
 703                "       jmp 2b\n"                                       \
 704                ".previous\n"                                           \
 705                ".section __ex_table,\"a\"\n"                           \
 706                "       .align 4\n"                                     \
 707                "       .long 4b,5b\n"                                  \
 708                "       .long 0b,3b\n"                                  \
 709                "       .long 1b,6b\n"                                  \
 710                ".previous"                                             \
 711                : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2)   \
 712                : "3"(size), "0"(size), "1"(to), "2"(from)              \
 713                : "memory");                                            \
 714} while (0)
 715
 716unsigned long __copy_to_user_ll(void __user *to, const void *from,
 717                                unsigned long n)
 718{
 719#ifndef CONFIG_X86_WP_WORKS_OK
 720        if (unlikely(boot_cpu_data.wp_works_ok == 0) &&
 721                        ((unsigned long )to) < TASK_SIZE) {
 722                /*
 723                 * When we are in an atomic section (see
 724                 * mm/filemap.c:file_read_actor), return the full
 725                 * length to take the slow path.
 726                 */
 727                if (in_atomic())
 728                        return n;
 729
 730                /* 
 731                 * CPU does not honor the WP bit when writing
 732                 * from supervisory mode, and due to preemption or SMP,
 733                 * the page tables can change at any time.
 734                 * Do it manually.      Manfred <manfred@colorfullife.com>
 735                 */
 736                while (n) {
 737                        unsigned long offset = ((unsigned long)to)%PAGE_SIZE;
 738                        unsigned long len = PAGE_SIZE - offset;
 739                        int retval;
 740                        struct page *pg;
 741                        void *maddr;
 742                        
 743                        if (len > n)
 744                                len = n;
 745
 746survive:
 747                        down_read(&current->mm->mmap_sem);
 748                        retval = get_user_pages(current, current->mm,
 749                                        (unsigned long )to, 1, 1, 0, &pg, NULL);
 750
 751                        if (retval == -ENOMEM && is_init(current)) {
 752                                up_read(&current->mm->mmap_sem);
 753                                congestion_wait(WRITE, HZ/50);
 754                                goto survive;
 755                        }
 756
 757                        if (retval != 1) {
 758                                up_read(&current->mm->mmap_sem);
 759                                break;
 760                        }
 761
 762                        maddr = kmap_atomic(pg, KM_USER0);
 763                        memcpy(maddr + offset, from, len);
 764                        kunmap_atomic(maddr, KM_USER0);
 765                        set_page_dirty_lock(pg);
 766                        put_page(pg);
 767                        up_read(&current->mm->mmap_sem);
 768
 769                        from += len;
 770                        to += len;
 771                        n -= len;
 772                }
 773                return n;
 774        }
 775#endif
 776        if (movsl_is_ok(to, from, n))
 777                __copy_user(to, from, n);
 778        else
 779                n = __copy_user_intel(to, from, n);
 780        return n;
 781}
 782EXPORT_SYMBOL(__copy_to_user_ll);
 783
 784unsigned long __copy_from_user_ll(void *to, const void __user *from,
 785                                        unsigned long n)
 786{
 787        if (movsl_is_ok(to, from, n))
 788                __copy_user_zeroing(to, from, n);
 789        else
 790                n = __copy_user_zeroing_intel(to, from, n);
 791        return n;
 792}
 793EXPORT_SYMBOL(__copy_from_user_ll);
 794
 795unsigned long __copy_from_user_ll_nozero(void *to, const void __user *from,
 796                                         unsigned long n)
 797{
 798        if (movsl_is_ok(to, from, n))
 799                __copy_user(to, from, n);
 800        else
 801                n = __copy_user_intel((void __user *)to,
 802                                      (const void *)from, n);
 803        return n;
 804}
 805EXPORT_SYMBOL(__copy_from_user_ll_nozero);
 806
 807unsigned long __copy_from_user_ll_nocache(void *to, const void __user *from,
 808                                        unsigned long n)
 809{
 810#ifdef CONFIG_X86_INTEL_USERCOPY
 811        if ( n > 64 && cpu_has_xmm2)
 812                n = __copy_user_zeroing_intel_nocache(to, from, n);
 813        else
 814                __copy_user_zeroing(to, from, n);
 815#else
 816        __copy_user_zeroing(to, from, n);
 817#endif
 818        return n;
 819}
 820
 821unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from,
 822                                        unsigned long n)
 823{
 824#ifdef CONFIG_X86_INTEL_USERCOPY
 825        if ( n > 64 && cpu_has_xmm2)
 826                n = __copy_user_intel_nocache(to, from, n);
 827        else
 828                __copy_user(to, from, n);
 829#else
 830        __copy_user(to, from, n);
 831#endif
 832        return n;
 833}
 834
 835/**
 836 * copy_to_user: - Copy a block of data into user space.
 837 * @to:   Destination address, in user space.
 838 * @from: Source address, in kernel space.
 839 * @n:    Number of bytes to copy.
 840 *
 841 * Context: User context only.  This function may sleep.
 842 *
 843 * Copy data from kernel space to user space.
 844 *
 845 * Returns number of bytes that could not be copied.
 846 * On success, this will be zero.
 847 */
 848unsigned long
 849copy_to_user(void __user *to, const void *from, unsigned long n)
 850{
 851        if (access_ok(VERIFY_WRITE, to, n))
 852                n = __copy_to_user(to, from, n);
 853        return n;
 854}
 855EXPORT_SYMBOL(copy_to_user);
 856
 857/**
 858 * copy_from_user: - Copy a block of data from user space.
 859 * @to:   Destination address, in kernel space.
 860 * @from: Source address, in user space.
 861 * @n:    Number of bytes to copy.
 862 *
 863 * Context: User context only.  This function may sleep.
 864 *
 865 * Copy data from user space to kernel space.
 866 *
 867 * Returns number of bytes that could not be copied.
 868 * On success, this will be zero.
 869 *
 870 * If some data could not be copied, this function will pad the copied
 871 * data to the requested size using zero bytes.
 872 */
 873unsigned long
 874copy_from_user(void *to, const void __user *from, unsigned long n)
 875{
 876        if (access_ok(VERIFY_READ, from, n))
 877                n = __copy_from_user(to, from, n);
 878        else
 879                memset(to, 0, n);
 880        return n;
 881}
 882EXPORT_SYMBOL(copy_from_user);
 883
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