include/asm-m68k/uaccess.h

   1 #ifndef __M68K_UACCESS_H
   2 #define __M68K_UACCESS_H
   3
   4 /*
   5  * User space memory access functions
   6  */
   7 #include <linux/errno.h>
   8 #include <linux/sched.h>
   9 #include <asm/segment.h>
  10
  11 #define VERIFY_READ     0
  12 #define VERIFY_WRITE    1
  13
  14 /* We let the MMU do all checking */
  15 #define access_ok(type,addr,size) 1
  16
  17 /*
  18  * The exception table consists of pairs of addresses: the first is the
  19  * address of an instruction that is allowed to fault, and the second is
  20  * the address at which the program should continue.  No registers are
  21  * modified, so it is entirely up to the continuation code to figure out
  22  * what to do.
  23  *
  24  * All the routines below use bits of fixup code that are out of line
  25  * with the main instruction path.  This means when everything is well,
  26  * we don't even have to jump over them.  Further, they do not intrude
  27  * on our cache or tlb entries.
  28  */
  29
  30 struct exception_table_entry
  31 {
  32         unsigned long insn, fixup;
  33 };
  34
  35
  36 /*
  37  * These are the main single-value transfer routines.  They automatically
  38  * use the right size if we just have the right pointer type.
  39  */
  40
  41 #define put_user(x, ptr)                                \
  42 ({                                                      \
  43     int __pu_err;                                       \
  44     typeof(*(ptr)) __pu_val = (x);                      \
  45     switch (sizeof (*(ptr))) {                          \
  46     case 1:                                             \
  47         __put_user_asm(__pu_err, __pu_val, ptr, b);     \
  48         break;                                          \
  49     case 2:                                             \
  50         __put_user_asm(__pu_err, __pu_val, ptr, w);     \
  51         break;                                          \
  52     case 4:                                             \
  53         __put_user_asm(__pu_err, __pu_val, ptr, l);     \
  54         break;                                          \
  55     case 8:                                             \
  56        __pu_err = __constant_copy_to_user(ptr, &__pu_val, 8);        \
  57        break;                                           \
  58     default:                                            \
  59         __pu_err = __put_user_bad();                    \
  60         break;                                          \
  61     }                                                   \
  62     __pu_err;                                           \
  63 })
  64 #define __put_user(x, ptr) put_user(x, ptr)
  65
  66 extern int __put_user_bad(void);
  67
  68 /*
  69  * Tell gcc we read from memory instead of writing: this is because
  70  * we do not write to any memory gcc knows about, so there are no
  71  * aliasing issues.
  72  */
  73 #define __put_user_asm(err,x,ptr,bwl)                   \
  74 __asm__ __volatile__                                    \
  75     ("21:moves" #bwl " %2,%1\n"                         \
  76      "1:\n"                                             \
  77      ".section .fixup,\"ax\"\n"                         \
  78      "   .even\n"                                       \
  79      "2: movel %3,%0\n"                                 \
  80      "   jra 1b\n"                                      \
  81      ".previous\n"                                      \
  82      ".section __ex_table,\"a\"\n"                      \
  83      "   .align 4\n"                                    \
  84      "   .long 21b,2b\n"                                \
  85      "   .long 1b,2b\n"                                 \
  86      ".previous"                                        \
  87      : "=d"(err)                                        \
  88      : "m"(*(ptr)), "r"(x), "i"(-EFAULT), "0"(0))
  89
  90 #define get_user(x, ptr)                                        \
  91 ({                                                              \
  92     int __gu_err;                                               \
  93     typeof(*(ptr)) __gu_val;                                    \
  94     switch (sizeof(*(ptr))) {                                   \
  95     case 1:                                                     \
  96         __get_user_asm(__gu_err, __gu_val, ptr, b, "=d");       \
  97         break;                                                  \
  98     case 2:                                                     \
  99         __get_user_asm(__gu_err, __gu_val, ptr, w, "=r");       \
 100         break;                                                  \
 101     case 4:                                                     \
 102         __get_user_asm(__gu_err, __gu_val, ptr, l, "=r");       \
 103         break;                                                  \
 104     case 8:                                                     \
 105         __gu_err = __constant_copy_from_user(&__gu_val, ptr, 8);  \
 106         break;                                                  \
 107     default:                                                    \
 108         __gu_val = 0;                                           \
 109         __gu_err = __get_user_bad();                            \
 110         break;                                                  \
 111     }                                                           \
 112     (x) = __gu_val;                                             \
 113     __gu_err;                                                   \
 114 })
 115 #define __get_user(x, ptr) get_user(x, ptr)
 116
 117 extern int __get_user_bad(void);
 118
 119 #define __get_user_asm(err,x,ptr,bwl,reg)       \
 120 __asm__ __volatile__                            \
 121     ("1: moves" #bwl " %2,%1\n"                 \
 122      "2:\n"                                     \
 123      ".section .fixup,\"ax\"\n"                 \
 124      "   .even\n"                               \
 125      "3: movel %3,%0\n"                         \
 126      "   sub" #bwl " %1,%1\n"                   \
 127      "   jra 2b\n"                              \
 128      ".previous\n"                              \
 129      ".section __ex_table,\"a\"\n"              \
 130      "   .align 4\n"                            \
 131      "   .long 1b,3b\n"                         \
 132      ".previous"                                \
 133      : "=d"(err), reg(x)                        \
 134      : "m"(*(ptr)), "i" (-EFAULT), "0"(0))
 135
 136 static inline unsigned long
 137 __generic_copy_from_user(void *to, const void *from, unsigned long n)
 138 {
 139     unsigned long tmp;
 140     __asm__ __volatile__
 141         ("   tstl %2\n"
 142          "   jeq 2f\n"
 143          "1: movesl (%1)+,%3\n"
 144          "   movel %3,(%0)+\n"
 145          "   subql #1,%2\n"
 146          "   jne 1b\n"
 147          "2: movel %4,%2\n"
 148          "   bclr #1,%2\n"
 149          "   jeq 4f\n"
 150          "3: movesw (%1)+,%3\n"
 151          "   movew %3,(%0)+\n"
 152          "4: bclr #0,%2\n"
 153          "   jeq 6f\n"
 154          "5: movesb (%1)+,%3\n"
 155          "   moveb %3,(%0)+\n"
 156          "6:\n"
 157          ".section .fixup,\"ax\"\n"
 158          "   .even\n"
 159          "7: movel %2,%%d0\n"
 160          "71:clrl (%0)+\n"
 161          "   subql #1,%%d0\n"
 162          "   jne 71b\n"
 163          "   lsll #2,%2\n"
 164          "   addl %4,%2\n"
 165          "   btst #1,%4\n"
 166          "   jne 81f\n"
 167          "   btst #0,%4\n"
 168          "   jne 91f\n"
 169          "   jra 6b\n"
 170          "8: addql #2,%2\n"
 171          "81:clrw (%0)+\n"
 172          "   btst #0,%4\n"
 173          "   jne 91f\n"
 174          "   jra 6b\n"
 175          "9: addql #1,%2\n"
 176          "91:clrb (%0)+\n"
 177          "   jra 6b\n"
 178          ".previous\n"
 179          ".section __ex_table,\"a\"\n"
 180          "   .align 4\n"
 181          "   .long 1b,7b\n"
 182          "   .long 3b,8b\n"
 183          "   .long 5b,9b\n"
 184          ".previous"
 185          : "=a"(to), "=a"(from), "=d"(n), "=&d"(tmp)
 186          : "d"(n & 3), "0"(to), "1"(from), "2"(n/4)
 187          : "d0", "memory");
 188     return n;
 189 }
 190
 191 static inline unsigned long
 192 __generic_copy_to_user(void *to, const void *from, unsigned long n)
 193 {
 194     unsigned long tmp;
 195     __asm__ __volatile__
 196         ("   tstl %2\n"
 197          "   jeq 3f\n"
 198          "1: movel (%1)+,%3\n"
 199          "22:movesl %3,(%0)+\n"
 200          "2: subql #1,%2\n"
 201          "   jne 1b\n"
 202          "3: movel %4,%2\n"
 203          "   bclr #1,%2\n"
 204          "   jeq 4f\n"
 205          "   movew (%1)+,%3\n"
 206          "24:movesw %3,(%0)+\n"
 207          "4: bclr #0,%2\n"
 208          "   jeq 5f\n"
 209          "   moveb (%1)+,%3\n"
 210          "25:movesb %3,(%0)+\n"
 211          "5:\n"
 212          ".section .fixup,\"ax\"\n"
 213          "   .even\n"
 214          "60:addql #1,%2\n"
 215          "6: lsll #2,%2\n"
 216          "   addl %4,%2\n"
 217          "   jra 5b\n"
 218          "7: addql #2,%2\n"
 219          "   jra 5b\n"
 220          "8: addql #1,%2\n"
 221          "   jra 5b\n"
 222          ".previous\n"
 223          ".section __ex_table,\"a\"\n"
 224          "   .align 4\n"
 225          "   .long 1b,60b\n"
 226          "   .long 22b,6b\n"
 227          "   .long 2b,6b\n"
 228          "   .long 24b,7b\n"
 229          "   .long 3b,60b\n"
 230          "   .long 4b,7b\n"
 231          "   .long 25b,8b\n"
 232          "   .long 5b,8b\n"
 233          ".previous"
 234          : "=a"(to), "=a"(from), "=d"(n), "=&d"(tmp)
 235          : "r"(n & 3), "0"(to), "1"(from), "2"(n / 4)
 236          : "memory");
 237     return n;
 238 }
 239
 240 #define __copy_from_user_big(to, from, n, fixup, copy)  \
 241     __asm__ __volatile__                                \
 242         ("10: movesl (%1)+,%%d0\n"                      \
 243          "    movel %%d0,(%0)+\n"                       \
 244          "    subql #1,%2\n"                            \
 245          "    jne 10b\n"                                \
 246          ".section .fixup,\"ax\"\n"                     \
 247          "    .even\n"                                  \
 248          "11: movel %2,%%d0\n"                          \
 249          "13: clrl (%0)+\n"                             \
 250          "    subql #1,%%d0\n"                          \
 251          "    jne 13b\n"                                \
 252          "    lsll #2,%2\n"                             \
 253          fixup "\n"                                     \
 254          "    jra 12f\n"                                \
 255          ".previous\n"                                  \
 256          ".section __ex_table,\"a\"\n"                  \
 257          "    .align 4\n"                               \
 258          "    .long 10b,11b\n"                          \
 259          ".previous\n"                                  \
 260          copy "\n"                                      \
 261          "12:"                                          \
 262          : "=a"(to), "=a"(from), "=d"(n)                \
 263          : "0"(to), "1"(from), "2"(n/4)                 \
 264          : "d0", "memory")
 265
 266 static inline unsigned long
 267 __constant_copy_from_user(void *to, const void *from, unsigned long n)
 268 {
 269     switch (n) {
 270     case 0:
 271         break;
 272     case 1:
 273         __asm__ __volatile__
 274             ("1: movesb (%1)+,%%d0\n"
 275              "   moveb %%d0,(%0)+\n"
 276              "2:\n"
 277              ".section .fixup,\"ax\"\n"
 278              "   .even\n"
 279              "3: addql #1,%2\n"
 280              "   clrb (%0)+\n"
 281              "   jra 2b\n"
 282              ".previous\n"
 283              ".section __ex_table,\"a\"\n"
 284              "   .align 4\n"
 285              "   .long 1b,3b\n"
 286              ".previous"
 287              : "=a"(to), "=a"(from), "=d"(n)
 288              : "0"(to), "1"(from), "2"(0)
 289              : "d0", "memory");
 290         break;
 291     case 2:
 292         __asm__ __volatile__
 293             ("1: movesw (%1)+,%%d0\n"
 294              "   movew %%d0,(%0)+\n"
 295              "2:\n"
 296              ".section .fixup,\"ax\"\n"
 297              "   .even\n"
 298              "3: addql #2,%2\n"
 299              "   clrw (%0)+\n"
 300              "   jra 2b\n"
 301              ".previous\n"
 302              ".section __ex_table,\"a\"\n"
 303              "   .align 4\n"
 304              "   .long 1b,3b\n"
 305              ".previous"
 306              : "=a"(to), "=a"(from), "=d"(n)
 307              : "0"(to), "1"(from), "2"(0)
 308              : "d0", "memory");
 309         break;
 310     case 3:
 311         __asm__ __volatile__
 312             ("1: movesw (%1)+,%%d0\n"
 313              "   movew %%d0,(%0)+\n"
 314              "2: movesb (%1)+,%%d0\n"
 315              "   moveb %%d0,(%0)+\n"
 316              "3:"
 317              ".section .fixup,\"ax\"\n"
 318              "   .even\n"
 319              "4: addql #2,%2\n"
 320              "   clrw (%0)+\n"
 321              "5: addql #1,%2\n"
 322              "   clrb (%0)+\n"
 323              "   jra 3b\n"
 324              ".previous\n"
 325              ".section __ex_table,\"a\"\n"
 326              "   .align 4\n"
 327              "   .long 1b,4b\n"
 328              "   .long 2b,5b\n"
 329              ".previous"
 330              : "=a"(to), "=a"(from), "=d"(n)
 331              : "0"(to), "1"(from), "2"(0)
 332              : "d0", "memory");
 333         break;
 334     case 4:
 335         __asm__ __volatile__
 336             ("1: movesl (%1)+,%%d0\n"
 337              "   movel %%d0,(%0)+\n"
 338              "2:"
 339              ".section .fixup,\"ax\"\n"
 340              "   .even\n"
 341              "3: addql #4,%2\n"
 342              "   clrl (%0)+\n"
 343              "   jra 2b\n"
 344              ".previous\n"
 345              ".section __ex_table,\"a\"\n"
 346              "   .align 4\n"
 347              "   .long 1b,3b\n"
 348              ".previous"
 349              : "=a"(to), "=a"(from), "=d"(n)
 350              : "0"(to), "1"(from), "2"(0)
 351              : "d0", "memory");
 352         break;
 353     case 8:
 354         __asm__ __volatile__
 355             ("1: movesl (%1)+,%%d0\n"
 356              "   movel %%d0,(%0)+\n"
 357              "2: movesl (%1)+,%%d0\n"
 358              "   movel %%d0,(%0)+\n"
 359              "3:"
 360              ".section .fixup,\"ax\"\n"
 361              "   .even\n"
 362              "4: addql #4,%2\n"
 363              "   clrl (%0)+\n"
 364              "5: addql #4,%2\n"
 365              "   clrl (%0)+\n"
 366              "   jra 3b\n"
 367              ".previous\n"
 368              ".section __ex_table,\"a\"\n"
 369              "   .align 4\n"
 370              "   .long 1b,4b\n"
 371              "   .long 2b,5b\n"
 372              ".previous"
 373              : "=a"(to), "=a"(from), "=d"(n)
 374              : "0"(to), "1"(from), "2"(0)
 375              : "d0", "memory");
 376         break;
 377     case 12:
 378         __asm__ __volatile__
 379             ("1: movesl (%1)+,%%d0\n"
 380              "   movel %%d0,(%0)+\n"
 381              "2: movesl (%1)+,%%d0\n"
 382              "   movel %%d0,(%0)+\n"
 383              "3: movesl (%1)+,%%d0\n"
 384              "   movel %%d0,(%0)+\n"
 385              "4:"
 386              ".section .fixup,\"ax\"\n"
 387              "   .even\n"
 388              "5: addql #4,%2\n"
 389              "   clrl (%0)+\n"
 390              "6: addql #4,%2\n"
 391              "   clrl (%0)+\n"
 392              "7: addql #4,%2\n"
 393              "   clrl (%0)+\n"
 394              "   jra 4b\n"
 395              ".previous\n"
 396              ".section __ex_table,\"a\"\n"
 397              "   .align 4\n"
 398              "   .long 1b,5b\n"
 399              "   .long 2b,6b\n"
 400              "   .long 3b,7b\n"
 401              ".previous"
 402              : "=a"(to), "=a"(from), "=d"(n)
 403              : "0"(to), "1"(from), "2"(0)
 404              : "d0", "memory");
 405         break;
 406     case 16:
 407         __asm__ __volatile__
 408             ("1: movesl (%1)+,%%d0\n"
 409              "   movel %%d0,(%0)+\n"
 410              "2: movesl (%1)+,%%d0\n"
 411              "   movel %%d0,(%0)+\n"
 412              "3: movesl (%1)+,%%d0\n"
 413              "   movel %%d0,(%0)+\n"
 414              "4: movesl (%1)+,%%d0\n"
 415              "   movel %%d0,(%0)+\n"
 416              "5:"
 417              ".section .fixup,\"ax\"\n"
 418              "   .even\n"
 419              "6: addql #4,%2\n"
 420              "   clrl (%0)+\n"
 421              "7: addql #4,%2\n"
 422              "   clrl (%0)+\n"
 423              "8: addql #4,%2\n"
 424              "   clrl (%0)+\n"
 425              "9: addql #4,%2\n"
 426              "   clrl (%0)+\n"
 427              "   jra 5b\n"
 428              ".previous\n"
 429              ".section __ex_table,\"a\"\n"
 430              "   .align 4\n"
 431              "   .long 1b,6b\n"
 432              "   .long 2b,7b\n"
 433              "   .long 3b,8b\n"
 434              "   .long 4b,9b\n"
 435              ".previous"
 436              : "=a"(to), "=a"(from), "=d"(n)
 437              : "0"(to), "1"(from), "2"(0)
 438              : "d0", "memory");
 439         break;
 440     default:
 441         switch (n & 3) {
 442         case 0:
 443             __copy_from_user_big(to, from, n, "", "");
 444             break;
 445         case 1:
 446             __copy_from_user_big(to, from, n,
 447                                  /* fixup */
 448                                  "1: addql #1,%2\n"
 449                                  "   clrb (%0)+",
 450                                  /* copy */
 451                                  "2: movesb (%1)+,%%d0\n"
 452                                  "   moveb %%d0,(%0)+\n"
 453                                  ".section __ex_table,\"a\"\n"
 454                                  "   .long 2b,1b\n"
 455                                  ".previous");
 456             break;
 457         case 2:
 458             __copy_from_user_big(to, from, n,
 459                                  /* fixup */
 460                                  "1: addql #2,%2\n"
 461                                  "   clrw (%0)+",
 462                                  /* copy */
 463                                  "2: movesw (%1)+,%%d0\n"
 464                                  "   movew %%d0,(%0)+\n"
 465                                  ".section __ex_table,\"a\"\n"
 466                                  "   .long 2b,1b\n"
 467                                  ".previous");
 468             break;
 469         case 3:
 470             __copy_from_user_big(to, from, n,
 471                                  /* fixup */
 472                                  "1: addql #2,%2\n"
 473                                  "   clrw (%0)+\n"
 474                                  "2: addql #1,%2\n"
 475                                  "   clrb (%0)+",
 476                                  /* copy */
 477                                  "3: movesw (%1)+,%%d0\n"
 478                                  "   movew %%d0,(%0)+\n"
 479                                  "4: movesb (%1)+,%%d0\n"
 480                                  "   moveb %%d0,(%0)+\n"
 481                                  ".section __ex_table,\"a\"\n"
 482                                  "   .long 3b,1b\n"
 483                                  "   .long 4b,2b\n"
 484                                  ".previous");
 485             break;
 486         }
 487         break;
 488     }
 489     return n;
 490 }
 491
 492 #define __copy_to_user_big(to, from, n, fixup, copy)    \
 493     __asm__ __volatile__                                \
 494         ("10: movel (%1)+,%%d0\n"                       \
 495          "31: movesl %%d0,(%0)+\n"                      \
 496          "11: subql #1,%2\n"                            \
 497          "    jne 10b\n"                                \
 498          "41:\n"                                        \
 499          ".section .fixup,\"ax\"\n"                     \
 500          "   .even\n"                                   \
 501          "22: addql #1,%2\n"                            \
 502          "12: lsll #2,%2\n"                             \
 503          fixup "\n"                                     \
 504          "    jra 13f\n"                                \
 505          ".previous\n"                                  \
 506          ".section __ex_table,\"a\"\n"                  \
 507          "    .align 4\n"                               \
 508          "    .long 10b,22b\n"                          \
 509          "    .long 31b,12b\n"                          \
 510          "    .long 11b,12b\n"                          \
 511          "    .long 41b,22b\n"                          \
 512          ".previous\n"                                  \
 513          copy "\n"                                      \
 514          "13:"                                          \
 515          : "=a"(to), "=a"(from), "=d"(n)                \
 516          : "0"(to), "1"(from), "2"(n/4)                 \
 517          : "d0", "memory")
 518
 519 #define __copy_to_user_inatomic __copy_to_user
 520 #define __copy_from_user_inatomic __copy_from_user
 521
 522 static inline unsigned long
 523 __constant_copy_to_user(void *to, const void *from, unsigned long n)
 524 {
 525     switch (n) {
 526     case 0:
 527         break;
 528     case 1:
 529         __asm__ __volatile__
 530             ("   moveb (%1)+,%%d0\n"
 531              "21:movesb %%d0,(%0)+\n"
 532              "1:\n"
 533              ".section .fixup,\"ax\"\n"
 534              "   .even\n"
 535              "2: addql #1,%2\n"
 536              "   jra 1b\n"
 537              ".previous\n"
 538              ".section __ex_table,\"a\"\n"
 539              "   .align 4\n  "
 540              "   .long 21b,2b\n"
 541              "   .long 1b,2b\n"
 542              ".previous"
 543              : "=a"(to), "=a"(from), "=d"(n)
 544              : "0"(to), "1"(from), "2"(0)
 545              : "d0", "memory");
 546         break;
 547     case 2:
 548         __asm__ __volatile__
 549             ("   movew (%1)+,%%d0\n"
 550              "21:movesw %%d0,(%0)+\n"
 551              "1:\n"
 552              ".section .fixup,\"ax\"\n"
 553              "   .even\n"
 554              "2: addql #2,%2\n"
 555              "   jra 1b\n"
 556              ".previous\n"
 557              ".section __ex_table,\"a\"\n"
 558              "   .align 4\n"
 559              "   .long 21b,2b\n"
 560              "   .long 1b,2b\n"
 561              ".previous"
 562              : "=a"(to), "=a"(from), "=d"(n)
 563              : "0"(to), "1"(from), "2"(0)
 564              : "d0", "memory");
 565         break;
 566     case 3:
 567         __asm__ __volatile__
 568             ("   movew (%1)+,%%d0\n"
 569              "21:movesw %%d0,(%0)+\n"
 570              "1: moveb (%1)+,%%d0\n"
 571              "22:movesb %%d0,(%0)+\n"
 572              "2:\n"
 573              ".section .fixup,\"ax\"\n"
 574              "   .even\n"
 575              "3: addql #2,%2\n"
 576              "4: addql #1,%2\n"
 577              "   jra 2b\n"
 578              ".previous\n"
 579              ".section __ex_table,\"a\"\n"
 580              "   .align 4\n"
 581              "   .long 21b,3b\n"
 582              "   .long 1b,3b\n"
 583              "   .long 22b,4b\n"
 584              "   .long 2b,4b\n"
 585              ".previous"
 586              : "=a"(to), "=a"(from), "=d"(n)
 587              : "0"(to), "1"(from), "2"(0)
 588              : "d0", "memory");
 589         break;
 590     case 4:
 591         __asm__ __volatile__
 592             ("   movel (%1)+,%%d0\n"
 593              "21:movesl %%d0,(%0)+\n"
 594              "1:\n"
 595              ".section .fixup,\"ax\"\n"
 596              "   .even\n"
 597              "2: addql #4,%2\n"
 598              "   jra 1b\n"
 599              ".previous\n"
 600              ".section __ex_table,\"a\"\n"
 601              "   .align 4\n"
 602              "   .long 21b,2b\n"
 603              "   .long 1b,2b\n"
 604              ".previous"
 605              : "=a"(to), "=a"(from), "=d"(n)
 606              : "0"(to), "1"(from), "2"(0)
 607              : "d0", "memory");
 608         break;
 609     case 8:
 610         __asm__ __volatile__
 611             ("   movel (%1)+,%%d0\n"
 612              "21:movesl %%d0,(%0)+\n"
 613              "1: movel (%1)+,%%d0\n"
 614              "22:movesl %%d0,(%0)+\n"
 615              "2:\n"
 616              ".section .fixup,\"ax\"\n"
 617              "   .even\n"
 618              "3: addql #4,%2\n"
 619              "4: addql #4,%2\n"
 620              "   jra 2b\n"
 621              ".previous\n"
 622              ".section __ex_table,\"a\"\n"
 623              "   .align 4\n"
 624              "   .long 21b,3b\n"
 625              "   .long 1b,3b\n"
 626              "   .long 22b,4b\n"
 627              "   .long 2b,4b\n"
 628              ".previous"
 629              : "=a"(to), "=a"(from), "=d"(n)
 630              : "0"(to), "1"(from), "2"(0)
 631              : "d0", "memory");
 632         break;
 633     case 12:
 634         __asm__ __volatile__
 635             ("   movel (%1)+,%%d0\n"
 636              "21:movesl %%d0,(%0)+\n"
 637              "1: movel (%1)+,%%d0\n"
 638              "22:movesl %%d0,(%0)+\n"
 639              "2: movel (%1)+,%%d0\n"
 640              "23:movesl %%d0,(%0)+\n"
 641              "3:\n"
 642              ".section .fixup,\"ax\"\n"
 643              "   .even\n"
 644              "4: addql #4,%2\n"
 645              "5: addql #4,%2\n"
 646              "6: addql #4,%2\n"
 647              "   jra 3b\n"
 648              ".previous\n"
 649              ".section __ex_table,\"a\"\n"
 650              "   .align 4\n"
 651              "   .long 21b,4b\n"
 652              "   .long 1b,4b\n"
 653              "   .long 22b,5b\n"
 654              "   .long 2b,5b\n"
 655              "   .long 23b,6b\n"
 656              "   .long 3b,6b\n"
 657              ".previous"
 658              : "=a"(to), "=a"(from), "=d"(n)
 659              : "0"(to), "1"(from), "2"(0)
 660              : "d0", "memory");
 661         break;
 662     case 16:
 663         __asm__ __volatile__
 664             ("   movel (%1)+,%%d0\n"
 665              "21:movesl %%d0,(%0)+\n"
 666              "1: movel (%1)+,%%d0\n"
 667              "22:movesl %%d0,(%0)+\n"
 668              "2: movel (%1)+,%%d0\n"
 669              "23:movesl %%d0,(%0)+\n"
 670              "3: movel (%1)+,%%d0\n"
 671              "24:movesl %%d0,(%0)+\n"
 672              "4:"
 673              ".section .fixup,\"ax\"\n"
 674              "   .even\n"
 675              "5: addql #4,%2\n"
 676              "6: addql #4,%2\n"
 677              "7: addql #4,%2\n"
 678              "8: addql #4,%2\n"
 679              "   jra 4b\n"
 680              ".previous\n"
 681              ".section __ex_table,\"a\"\n"
 682              "   .align 4\n"
 683              "   .long 21b,5b\n"
 684              "   .long 1b,5b\n"
 685              "   .long 22b,6b\n"
 686              "   .long 2b,6b\n"
 687              "   .long 23b,7b\n"
 688              "   .long 3b,7b\n"
 689              "   .long 24b,8b\n"
 690              "   .long 4b,8b\n"
 691              ".previous"
 692              : "=a"(to), "=a"(from), "=d"(n)
 693              : "0"(to), "1"(from), "2"(0)
 694              : "d0", "memory");
 695         break;
 696     default:
 697         switch (n & 3) {
 698         case 0:
 699             __copy_to_user_big(to, from, n, "", "");
 700             break;
 701         case 1:
 702             __copy_to_user_big(to, from, n,
 703                                /* fixup */
 704                                "1: addql #1,%2",
 705                                /* copy */
 706                                "   moveb (%1)+,%%d0\n"
 707                                "22:movesb %%d0,(%0)+\n"
 708                                "2:"
 709                                ".section __ex_table,\"a\"\n"
 710                                "   .long 22b,1b\n"
 711                                "   .long 2b,1b\n"
 712                                ".previous");
 713             break;
 714         case 2:
 715             __copy_to_user_big(to, from, n,
 716                                /* fixup */
 717                                "1: addql #2,%2",
 718                                /* copy */
 719                                "   movew (%1)+,%%d0\n"
 720                                "22:movesw %%d0,(%0)+\n"
 721                                "2:"
 722                                ".section __ex_table,\"a\"\n"
 723                                "   .long 22b,1b\n"
 724                                "   .long 2b,1b\n"
 725                                ".previous");
 726             break;
 727         case 3:
 728             __copy_to_user_big(to, from, n,
 729                                /* fixup */
 730                                "1: addql #2,%2\n"
 731                                "2: addql #1,%2",
 732                                /* copy */
 733                                "   movew (%1)+,%%d0\n"
 734                                "23:movesw %%d0,(%0)+\n"
 735                                "3: moveb (%1)+,%%d0\n"
 736                                "24:movesb %%d0,(%0)+\n"
 737                                "4:"
 738                                ".section __ex_table,\"a\"\n"
 739                                "   .long 23b,1b\n"
 740                                "   .long 3b,1b\n"
 741                                "   .long 24b,2b\n"
 742                                "   .long 4b,2b\n"
 743                                ".previous");
 744             break;
 745         }
 746         break;
 747     }
 748     return n;
 749 }
 750
 751 #define copy_from_user(to, from, n)             \
 752 (__builtin_constant_p(n) ?                      \
 753  __constant_copy_from_user(to, from, n) :       \
 754  __generic_copy_from_user(to, from, n))
 755
 756 #define copy_to_user(to, from, n)               \
 757 (__builtin_constant_p(n) ?                      \
 758  __constant_copy_to_user(to, from, n) :         \
 759  __generic_copy_to_user(to, from, n))
 760
 761 #define __copy_from_user(to, from, n) copy_from_user(to, from, n)
 762 #define __copy_to_user(to, from, n) copy_to_user(to, from, n)
 763
 764 /*
 765  * Copy a null terminated string from userspace.
 766  */
 767
 768 static inline long
 769 strncpy_from_user(char *dst, const char *src, long count)
 770 {
 771     long res;
 772     if (count == 0) return count;
 773     __asm__ __volatile__
 774         ("1: movesb (%2)+,%%d0\n"
 775          "12:moveb %%d0,(%1)+\n"
 776          "   jeq 2f\n"
 777          "   subql #1,%3\n"
 778          "   jne 1b\n"
 779          "2: subl %3,%0\n"
 780          "3:\n"
 781          ".section .fixup,\"ax\"\n"
 782          "   .even\n"
 783          "4: movel %4,%0\n"
 784          "   jra 3b\n"
 785          ".previous\n"
 786          ".section __ex_table,\"a\"\n"
 787          "   .align 4\n"
 788          "   .long 1b,4b\n"
 789          "   .long 12b,4b\n"
 790          ".previous"
 791          : "=d"(res), "=a"(dst), "=a"(src), "=d"(count)
 792          : "i"(-EFAULT), "0"(count), "1"(dst), "2"(src), "3"(count)
 793          : "d0", "memory");
 794     return res;
 795 }
 796
 797 /*
 798  * Return the size of a string (including the ending 0)
 799  *
 800  * Return 0 on exception, a value greater than N if too long
 801  */
 802 static inline long strnlen_user(const char *src, long n)
 803 {
 804         long res;
 805
 806         res = -(long)src;
 807         __asm__ __volatile__
 808                 ("1:\n"
 809                  "   tstl %2\n"
 810                  "   jeq 3f\n"
 811                  "2: movesb (%1)+,%%d0\n"
 812                  "22:\n"
 813                  "   subql #1,%2\n"
 814                  "   tstb %%d0\n"
 815                  "   jne 1b\n"
 816                  "   jra 4f\n"
 817                  "3:\n"
 818                  "   addql #1,%0\n"
 819                  "4:\n"
 820                  "   addl %1,%0\n"
 821                  "5:\n"
 822                  ".section .fixup,\"ax\"\n"
 823                  "   .even\n"
 824                  "6: moveq %3,%0\n"
 825                  "   jra 5b\n"
 826                  ".previous\n"
 827                  ".section __ex_table,\"a\"\n"
 828                  "   .align 4\n"
 829                  "   .long 2b,6b\n"
 830                  "   .long 22b,6b\n"
 831                  ".previous"
 832                  : "=d"(res), "=a"(src), "=d"(n)
 833                  : "i"(0), "0"(res), "1"(src), "2"(n)
 834                  : "d0");
 835         return res;
 836 }
 837
 838 #define strlen_user(str) strnlen_user(str, 32767)
 839
 840 /*
 841  * Zero Userspace
 842  */
 843
 844 static inline unsigned long
 845 clear_user(void *to, unsigned long n)
 846 {
 847     __asm__ __volatile__
 848         ("   tstl %1\n"
 849          "   jeq 3f\n"
 850          "1: movesl %3,(%0)+\n"
 851          "2: subql #1,%1\n"
 852          "   jne 1b\n"
 853          "3: movel %2,%1\n"
 854          "   bclr #1,%1\n"
 855          "   jeq 4f\n"
 856          "24:movesw %3,(%0)+\n"
 857          "4: bclr #0,%1\n"
 858          "   jeq 5f\n"
 859          "25:movesb %3,(%0)+\n"
 860          "5:\n"
 861          ".section .fixup,\"ax\"\n"
 862          "   .even\n"
 863          "61:addql #1,%1\n"
 864          "6: lsll #2,%1\n"
 865          "   addl %2,%1\n"
 866          "   jra 5b\n"
 867          "7: addql #2,%1\n"
 868          "   jra 5b\n"
 869          "8: addql #1,%1\n"
 870          "   jra 5b\n"
 871          ".previous\n"
 872          ".section __ex_table,\"a\"\n"
 873          "   .align 4\n"
 874          "   .long 1b,61b\n"
 875          "   .long 2b,6b\n"
 876          "   .long 3b,61b\n"
 877          "   .long 24b,7b\n"
 878          "   .long 4b,7b\n"
 879          "   .long 25b,8b\n"
 880          "   .long 5b,8b\n"
 881          ".previous"
 882          : "=a"(to), "=d"(n)
 883          : "r"(n & 3), "r"(0), "0"(to), "1"(n/4));
 884     return n;
 885 }
 886
 887 #endif /* _M68K_UACCESS_H */