git.oblomov.eu Git - linux-2.6/blob - 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 <linux/interrupt.h>
  14 #include <asm/uaccess.h>
  15 #include <asm/mmx.h>
  16
  17 static 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)                          \
  33 do {                                                                       \
  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  */
  81 long
  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 }
  88 EXPORT_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  */
 108 long
 109 strncpy_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 }
 116 EXPORT_SYMBOL(strncpy_from_user);
 117
 118 /*
 119  * Zero Userspace
 120  */
 121
 122 #define __do_clear_user(addr,size)                                      \
 123 do {                                                                    \
 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  */
 154 unsigned long
 155 clear_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 }
 162 EXPORT_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  */
 175 unsigned long
 176 __clear_user(void __user *to, unsigned long n)
 177 {
 178         __do_clear_user(to, n);
 179         return n;
 180 }
 181 EXPORT_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  */
 194 long 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 }
 225 EXPORT_SYMBOL(strnlen_user);
 226
 227 #ifdef CONFIG_X86_INTEL_USERCOPY
 228 static 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
 335 static 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
 435 static 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
 532 static 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  */
 629 unsigned long __copy_user_zeroing_intel(void *to, const void __user *from,
 630                                         unsigned long size);
 631 unsigned long __copy_user_intel(void __user *to, const void *from,
 632                                         unsigned long size);
 633 unsigned 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)                                       \
 639 do {                                                                    \
 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)                               \
 675 do {                                                                    \
 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
 716 unsigned 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
 746 survive:
 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 }
 782 EXPORT_SYMBOL(__copy_to_user_ll);
 783
 784 unsigned 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 }
 793 EXPORT_SYMBOL(__copy_from_user_ll);
 794
 795 unsigned 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 }
 805 EXPORT_SYMBOL(__copy_from_user_ll_nozero);
 806
 807 unsigned 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
 821 unsigned 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  */
 848 unsigned long
 849 copy_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 }
 855 EXPORT_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  */
 873 unsigned long
 874 copy_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 }
 882 EXPORT_SYMBOL(copy_from_user);