arch/i386/lib/usercopy.c

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