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     __chk_user_ptr(ptr);                                \
  46     switch (sizeof (*(ptr))) {                          \
  47     case 1:                                             \
  48         __put_user_asm(__pu_err, __pu_val, ptr, b);     \
  49         break;                                          \
  50     case 2:                                             \
  51         __put_user_asm(__pu_err, __pu_val, ptr, w);     \
  52         break;                                          \
  53     case 4:                                             \
  54         __put_user_asm(__pu_err, __pu_val, ptr, l);     \
  55         break;                                          \
  56     case 8:                                             \
  57        __pu_err = __constant_copy_to_user(ptr, &__pu_val, 8);        \
  58        break;                                           \
  59     default:                                            \
  60         __pu_err = __put_user_bad();                    \
  61         break;                                          \
  62     }                                                   \
  63     __pu_err;                                           \
  64 })
  65 #define __put_user(x, ptr) put_user(x, ptr)
  66
  67 extern int __put_user_bad(void);
  68
  69 /*
  70  * Tell gcc we read from memory instead of writing: this is because
  71  * we do not write to any memory gcc knows about, so there are no
  72  * aliasing issues.
  73  */
  74 #define __put_user_asm(err,x,ptr,bwl)                   \
  75 __asm__ __volatile__                                    \
  76     ("21:moves" #bwl " %2,%1\n"                         \
  77      "1:\n"                                             \
  78      ".section .fixup,\"ax\"\n"                         \
  79      "   .even\n"                                       \
  80      "2: movel %3,%0\n"                                 \
  81      "   jra 1b\n"                                      \
  82      ".previous\n"                                      \
  83      ".section __ex_table,\"a\"\n"                      \
  84      "   .align 4\n"                                    \
  85      "   .long 21b,2b\n"                                \
  86      "   .long 1b,2b\n"                                 \
  87      ".previous"                                        \
  88      : "=d"(err)                                        \
  89      : "m"(*(ptr)), "r"(x), "i"(-EFAULT), "0"(0))
  90
  91 #define get_user(x, ptr)                                        \
  92 ({                                                              \
  93     int __gu_err;                                               \
  94     typeof(*(ptr)) __gu_val;                                    \
  95     __chk_user_ptr(ptr);                                        \
  96     switch (sizeof(*(ptr))) {                                   \
  97     case 1:                                                     \
  98         __get_user_asm(__gu_err, __gu_val, ptr, b, "=d");       \
  99         break;                                                  \
 100     case 2:                                                     \
 101         __get_user_asm(__gu_err, __gu_val, ptr, w, "=r");       \
 102         break;                                                  \
 103     case 4:                                                     \
 104         __get_user_asm(__gu_err, __gu_val, ptr, l, "=r");       \
 105         break;                                                  \
 106     case 8:                                                     \
 107         __gu_err = __constant_copy_from_user(&__gu_val, ptr, 8);  \
 108         break;                                                  \
 109     default:                                                    \
 110         __gu_val = (typeof(*(ptr)))0;                           \
 111         __gu_err = __get_user_bad();                            \
 112         break;                                                  \
 113     }                                                           \
 114     (x) = __gu_val;                                             \
 115     __gu_err;                                                   \
 116 })
 117 #define __get_user(x, ptr) get_user(x, ptr)
 118
 119 extern int __get_user_bad(void);
 120
 121 #define __get_user_asm(err,x,ptr,bwl,reg)       \
 122 __asm__ __volatile__                            \
 123     ("1: moves" #bwl " %2,%1\n"                 \
 124      "2:\n"                                     \
 125      ".section .fixup,\"ax\"\n"                 \
 126      "   .even\n"                               \
 127      "3: movel %3,%0\n"                         \
 128      "   sub" #bwl " %1,%1\n"                   \
 129      "   jra 2b\n"                              \
 130      ".previous\n"                              \
 131      ".section __ex_table,\"a\"\n"              \
 132      "   .align 4\n"                            \
 133      "   .long 1b,3b\n"                         \
 134      ".previous"                                \
 135      : "=d"(err), reg(x)                        \
 136      : "m"(*(ptr)), "i" (-EFAULT), "0"(0))
 137
 138 static inline unsigned long
 139 __generic_copy_from_user(void *to, const void __user *from, unsigned long n)
 140 {
 141     unsigned long tmp;
 142     __asm__ __volatile__
 143         ("   tstl %2\n"
 144          "   jeq 2f\n"
 145          "1: movesl (%1)+,%3\n"
 146          "   movel %3,(%0)+\n"
 147          "   subql #1,%2\n"
 148          "   jne 1b\n"
 149          "2: movel %4,%2\n"
 150          "   bclr #1,%2\n"
 151          "   jeq 4f\n"
 152          "3: movesw (%1)+,%3\n"
 153          "   movew %3,(%0)+\n"
 154          "4: bclr #0,%2\n"
 155          "   jeq 6f\n"
 156          "5: movesb (%1)+,%3\n"
 157          "   moveb %3,(%0)+\n"
 158          "6:\n"
 159          ".section .fixup,\"ax\"\n"
 160          "   .even\n"
 161          "7: movel %2,%%d0\n"
 162          "71:clrl (%0)+\n"
 163          "   subql #1,%%d0\n"
 164          "   jne 71b\n"
 165          "   lsll #2,%2\n"
 166          "   addl %4,%2\n"
 167          "   btst #1,%4\n"
 168          "   jne 81f\n"
 169          "   btst #0,%4\n"
 170          "   jne 91f\n"
 171          "   jra 6b\n"
 172          "8: addql #2,%2\n"
 173          "81:clrw (%0)+\n"
 174          "   btst #0,%4\n"
 175          "   jne 91f\n"
 176          "   jra 6b\n"
 177          "9: addql #1,%2\n"
 178          "91:clrb (%0)+\n"
 179          "   jra 6b\n"
 180          ".previous\n"
 181          ".section __ex_table,\"a\"\n"
 182          "   .align 4\n"
 183          "   .long 1b,7b\n"
 184          "   .long 3b,8b\n"
 185          "   .long 5b,9b\n"
 186          ".previous"
 187          : "=a"(to), "=a"(from), "=d"(n), "=&d"(tmp)
 188          : "d"(n & 3), "0"(to), "1"(from), "2"(n/4)
 189          : "d0", "memory");
 190     return n;
 191 }
 192
 193 static inline unsigned long
 194 __generic_copy_to_user(void __user *to, const void *from, unsigned long n)
 195 {
 196     unsigned long tmp;
 197     __asm__ __volatile__
 198         ("   tstl %2\n"
 199          "   jeq 3f\n"
 200          "1: movel (%1)+,%3\n"
 201          "22:movesl %3,(%0)+\n"
 202          "2: subql #1,%2\n"
 203          "   jne 1b\n"
 204          "3: movel %4,%2\n"
 205          "   bclr #1,%2\n"
 206          "   jeq 4f\n"
 207          "   movew (%1)+,%3\n"
 208          "24:movesw %3,(%0)+\n"
 209          "4: bclr #0,%2\n"
 210          "   jeq 5f\n"
 211          "   moveb (%1)+,%3\n"
 212          "25:movesb %3,(%0)+\n"
 213          "5:\n"
 214          ".section .fixup,\"ax\"\n"
 215          "   .even\n"
 216          "60:addql #1,%2\n"
 217          "6: lsll #2,%2\n"
 218          "   addl %4,%2\n"
 219          "   jra 5b\n"
 220          "7: addql #2,%2\n"
 221          "   jra 5b\n"
 222          "8: addql #1,%2\n"
 223          "   jra 5b\n"
 224          ".previous\n"
 225          ".section __ex_table,\"a\"\n"
 226          "   .align 4\n"
 227          "   .long 1b,60b\n"
 228          "   .long 22b,6b\n"
 229          "   .long 2b,6b\n"
 230          "   .long 24b,7b\n"
 231          "   .long 3b,60b\n"
 232          "   .long 4b,7b\n"
 233          "   .long 25b,8b\n"
 234          "   .long 5b,8b\n"
 235          ".previous"
 236          : "=a"(to), "=a"(from), "=d"(n), "=&d"(tmp)
 237          : "r"(n & 3), "0"(to), "1"(from), "2"(n / 4)
 238          : "memory");
 239     return n;
 240 }
 241
 242 #define __copy_from_user_big(to, from, n, fixup, copy)  \
 243     __asm__ __volatile__                                \
 244         ("10: movesl (%1)+,%%d0\n"                      \
 245          "    movel %%d0,(%0)+\n"                       \
 246          "    subql #1,%2\n"                            \
 247          "    jne 10b\n"                                \
 248          ".section .fixup,\"ax\"\n"                     \
 249          "    .even\n"                                  \
 250          "11: movel %2,%%d0\n"                          \
 251          "13: clrl (%0)+\n"                             \
 252          "    subql #1,%%d0\n"                          \
 253          "    jne 13b\n"                                \
 254          "    lsll #2,%2\n"                             \
 255          fixup "\n"                                     \
 256          "    jra 12f\n"                                \
 257          ".previous\n"                                  \
 258          ".section __ex_table,\"a\"\n"                  \
 259          "    .align 4\n"                               \
 260          "    .long 10b,11b\n"                          \
 261          ".previous\n"                                  \
 262          copy "\n"                                      \
 263          "12:"                                          \
 264          : "=a"(to), "=a"(from), "=d"(n)                \
 265          : "0"(to), "1"(from), "2"(n/4)                 \
 266          : "d0", "memory")
 267
 268 static inline unsigned long
 269 __constant_copy_from_user(void *to, const void __user *from, unsigned long n)
 270 {
 271     switch (n) {
 272     case 0:
 273         break;
 274     case 1:
 275         __asm__ __volatile__
 276             ("1: movesb (%1)+,%%d0\n"
 277              "   moveb %%d0,(%0)+\n"
 278              "2:\n"
 279              ".section .fixup,\"ax\"\n"
 280              "   .even\n"
 281              "3: addql #1,%2\n"
 282              "   clrb (%0)+\n"
 283              "   jra 2b\n"
 284              ".previous\n"
 285              ".section __ex_table,\"a\"\n"
 286              "   .align 4\n"
 287              "   .long 1b,3b\n"
 288              ".previous"
 289              : "=a"(to), "=a"(from), "=d"(n)
 290              : "0"(to), "1"(from), "2"(0)
 291              : "d0", "memory");
 292         break;
 293     case 2:
 294         __asm__ __volatile__
 295             ("1: movesw (%1)+,%%d0\n"
 296              "   movew %%d0,(%0)+\n"
 297              "2:\n"
 298              ".section .fixup,\"ax\"\n"
 299              "   .even\n"
 300              "3: addql #2,%2\n"
 301              "   clrw (%0)+\n"
 302              "   jra 2b\n"
 303              ".previous\n"
 304              ".section __ex_table,\"a\"\n"
 305              "   .align 4\n"
 306              "   .long 1b,3b\n"
 307              ".previous"
 308              : "=a"(to), "=a"(from), "=d"(n)
 309              : "0"(to), "1"(from), "2"(0)
 310              : "d0", "memory");
 311         break;
 312     case 3:
 313         __asm__ __volatile__
 314             ("1: movesw (%1)+,%%d0\n"
 315              "   movew %%d0,(%0)+\n"
 316              "2: movesb (%1)+,%%d0\n"
 317              "   moveb %%d0,(%0)+\n"
 318              "3:"
 319              ".section .fixup,\"ax\"\n"
 320              "   .even\n"
 321              "4: addql #2,%2\n"
 322              "   clrw (%0)+\n"
 323              "5: addql #1,%2\n"
 324              "   clrb (%0)+\n"
 325              "   jra 3b\n"
 326              ".previous\n"
 327              ".section __ex_table,\"a\"\n"
 328              "   .align 4\n"
 329              "   .long 1b,4b\n"
 330              "   .long 2b,5b\n"
 331              ".previous"
 332              : "=a"(to), "=a"(from), "=d"(n)
 333              : "0"(to), "1"(from), "2"(0)
 334              : "d0", "memory");
 335         break;
 336     case 4:
 337         __asm__ __volatile__
 338             ("1: movesl (%1)+,%%d0\n"
 339              "   movel %%d0,(%0)+\n"
 340              "2:"
 341              ".section .fixup,\"ax\"\n"
 342              "   .even\n"
 343              "3: addql #4,%2\n"
 344              "   clrl (%0)+\n"
 345              "   jra 2b\n"
 346              ".previous\n"
 347              ".section __ex_table,\"a\"\n"
 348              "   .align 4\n"
 349              "   .long 1b,3b\n"
 350              ".previous"
 351              : "=a"(to), "=a"(from), "=d"(n)
 352              : "0"(to), "1"(from), "2"(0)
 353              : "d0", "memory");
 354         break;
 355     case 8:
 356         __asm__ __volatile__
 357             ("1: movesl (%1)+,%%d0\n"
 358              "   movel %%d0,(%0)+\n"
 359              "2: movesl (%1)+,%%d0\n"
 360              "   movel %%d0,(%0)+\n"
 361              "3:"
 362              ".section .fixup,\"ax\"\n"
 363              "   .even\n"
 364              "4: addql #4,%2\n"
 365              "   clrl (%0)+\n"
 366              "5: addql #4,%2\n"
 367              "   clrl (%0)+\n"
 368              "   jra 3b\n"
 369              ".previous\n"
 370              ".section __ex_table,\"a\"\n"
 371              "   .align 4\n"
 372              "   .long 1b,4b\n"
 373              "   .long 2b,5b\n"
 374              ".previous"
 375              : "=a"(to), "=a"(from), "=d"(n)
 376              : "0"(to), "1"(from), "2"(0)
 377              : "d0", "memory");
 378         break;
 379     case 12:
 380         __asm__ __volatile__
 381             ("1: movesl (%1)+,%%d0\n"
 382              "   movel %%d0,(%0)+\n"
 383              "2: movesl (%1)+,%%d0\n"
 384              "   movel %%d0,(%0)+\n"
 385              "3: movesl (%1)+,%%d0\n"
 386              "   movel %%d0,(%0)+\n"
 387              "4:"
 388              ".section .fixup,\"ax\"\n"
 389              "   .even\n"
 390              "5: addql #4,%2\n"
 391              "   clrl (%0)+\n"
 392              "6: addql #4,%2\n"
 393              "   clrl (%0)+\n"
 394              "7: addql #4,%2\n"
 395              "   clrl (%0)+\n"
 396              "   jra 4b\n"
 397              ".previous\n"
 398              ".section __ex_table,\"a\"\n"
 399              "   .align 4\n"
 400              "   .long 1b,5b\n"
 401              "   .long 2b,6b\n"
 402              "   .long 3b,7b\n"
 403              ".previous"
 404              : "=a"(to), "=a"(from), "=d"(n)
 405              : "0"(to), "1"(from), "2"(0)
 406              : "d0", "memory");
 407         break;
 408     case 16:
 409         __asm__ __volatile__
 410             ("1: movesl (%1)+,%%d0\n"
 411              "   movel %%d0,(%0)+\n"
 412              "2: movesl (%1)+,%%d0\n"
 413              "   movel %%d0,(%0)+\n"
 414              "3: movesl (%1)+,%%d0\n"
 415              "   movel %%d0,(%0)+\n"
 416              "4: movesl (%1)+,%%d0\n"
 417              "   movel %%d0,(%0)+\n"
 418              "5:"
 419              ".section .fixup,\"ax\"\n"
 420              "   .even\n"
 421              "6: addql #4,%2\n"
 422              "   clrl (%0)+\n"
 423              "7: addql #4,%2\n"
 424              "   clrl (%0)+\n"
 425              "8: addql #4,%2\n"
 426              "   clrl (%0)+\n"
 427              "9: addql #4,%2\n"
 428              "   clrl (%0)+\n"
 429              "   jra 5b\n"
 430              ".previous\n"
 431              ".section __ex_table,\"a\"\n"
 432              "   .align 4\n"
 433              "   .long 1b,6b\n"
 434              "   .long 2b,7b\n"
 435              "   .long 3b,8b\n"
 436              "   .long 4b,9b\n"
 437              ".previous"
 438              : "=a"(to), "=a"(from), "=d"(n)
 439              : "0"(to), "1"(from), "2"(0)
 440              : "d0", "memory");
 441         break;
 442     default:
 443         switch (n & 3) {
 444         case 0:
 445             __copy_from_user_big(to, from, n, "", "");
 446             break;
 447         case 1:
 448             __copy_from_user_big(to, from, n,
 449                                  /* fixup */
 450                                  "1: addql #1,%2\n"
 451                                  "   clrb (%0)+",
 452                                  /* copy */
 453                                  "2: movesb (%1)+,%%d0\n"
 454                                  "   moveb %%d0,(%0)+\n"
 455                                  ".section __ex_table,\"a\"\n"
 456                                  "   .long 2b,1b\n"
 457                                  ".previous");
 458             break;
 459         case 2:
 460             __copy_from_user_big(to, from, n,
 461                                  /* fixup */
 462                                  "1: addql #2,%2\n"
 463                                  "   clrw (%0)+",
 464                                  /* copy */
 465                                  "2: movesw (%1)+,%%d0\n"
 466                                  "   movew %%d0,(%0)+\n"
 467                                  ".section __ex_table,\"a\"\n"
 468                                  "   .long 2b,1b\n"
 469                                  ".previous");
 470             break;
 471         case 3:
 472             __copy_from_user_big(to, from, n,
 473                                  /* fixup */
 474                                  "1: addql #2,%2\n"
 475                                  "   clrw (%0)+\n"
 476                                  "2: addql #1,%2\n"
 477                                  "   clrb (%0)+",
 478                                  /* copy */
 479                                  "3: movesw (%1)+,%%d0\n"
 480                                  "   movew %%d0,(%0)+\n"
 481                                  "4: movesb (%1)+,%%d0\n"
 482                                  "   moveb %%d0,(%0)+\n"
 483                                  ".section __ex_table,\"a\"\n"
 484                                  "   .long 3b,1b\n"
 485                                  "   .long 4b,2b\n"
 486                                  ".previous");
 487             break;
 488         }
 489         break;
 490     }
 491     return n;
 492 }
 493
 494 #define __copy_to_user_big(to, from, n, fixup, copy)    \
 495     __asm__ __volatile__                                \
 496         ("10: movel (%1)+,%%d0\n"                       \
 497          "31: movesl %%d0,(%0)+\n"                      \
 498          "11: subql #1,%2\n"                            \
 499          "    jne 10b\n"                                \
 500          "41:\n"                                        \
 501          ".section .fixup,\"ax\"\n"                     \
 502          "   .even\n"                                   \
 503          "22: addql #1,%2\n"                            \
 504          "12: lsll #2,%2\n"                             \
 505          fixup "\n"                                     \
 506          "    jra 13f\n"                                \
 507          ".previous\n"                                  \
 508          ".section __ex_table,\"a\"\n"                  \
 509          "    .align 4\n"                               \
 510          "    .long 10b,22b\n"                          \
 511          "    .long 31b,12b\n"                          \
 512          "    .long 11b,12b\n"                          \
 513          "    .long 41b,22b\n"                          \
 514          ".previous\n"                                  \
 515          copy "\n"                                      \
 516          "13:"                                          \
 517          : "=a"(to), "=a"(from), "=d"(n)                \
 518          : "0"(to), "1"(from), "2"(n/4)                 \
 519          : "d0", "memory")
 520
 521 #define __copy_to_user_inatomic __copy_to_user
 522 #define __copy_from_user_inatomic __copy_from_user
 523
 524 static inline unsigned long
 525 __constant_copy_to_user(void __user *to, const void *from, unsigned long n)
 526 {
 527     switch (n) {
 528     case 0:
 529         break;
 530     case 1:
 531         __asm__ __volatile__
 532             ("   moveb (%1)+,%%d0\n"
 533              "21:movesb %%d0,(%0)+\n"
 534              "1:\n"
 535              ".section .fixup,\"ax\"\n"
 536              "   .even\n"
 537              "2: addql #1,%2\n"
 538              "   jra 1b\n"
 539              ".previous\n"
 540              ".section __ex_table,\"a\"\n"
 541              "   .align 4\n  "
 542              "   .long 21b,2b\n"
 543              "   .long 1b,2b\n"
 544              ".previous"
 545              : "=a"(to), "=a"(from), "=d"(n)
 546              : "0"(to), "1"(from), "2"(0)
 547              : "d0", "memory");
 548         break;
 549     case 2:
 550         __asm__ __volatile__
 551             ("   movew (%1)+,%%d0\n"
 552              "21:movesw %%d0,(%0)+\n"
 553              "1:\n"
 554              ".section .fixup,\"ax\"\n"
 555              "   .even\n"
 556              "2: addql #2,%2\n"
 557              "   jra 1b\n"
 558              ".previous\n"
 559              ".section __ex_table,\"a\"\n"
 560              "   .align 4\n"
 561              "   .long 21b,2b\n"
 562              "   .long 1b,2b\n"
 563              ".previous"
 564              : "=a"(to), "=a"(from), "=d"(n)
 565              : "0"(to), "1"(from), "2"(0)
 566              : "d0", "memory");
 567         break;
 568     case 3:
 569         __asm__ __volatile__
 570             ("   movew (%1)+,%%d0\n"
 571              "21:movesw %%d0,(%0)+\n"
 572              "1: moveb (%1)+,%%d0\n"
 573              "22:movesb %%d0,(%0)+\n"
 574              "2:\n"
 575              ".section .fixup,\"ax\"\n"
 576              "   .even\n"
 577              "3: addql #2,%2\n"
 578              "4: addql #1,%2\n"
 579              "   jra 2b\n"
 580              ".previous\n"
 581              ".section __ex_table,\"a\"\n"
 582              "   .align 4\n"
 583              "   .long 21b,3b\n"
 584              "   .long 1b,3b\n"
 585              "   .long 22b,4b\n"
 586              "   .long 2b,4b\n"
 587              ".previous"
 588              : "=a"(to), "=a"(from), "=d"(n)
 589              : "0"(to), "1"(from), "2"(0)
 590              : "d0", "memory");
 591         break;
 592     case 4:
 593         __asm__ __volatile__
 594             ("   movel (%1)+,%%d0\n"
 595              "21:movesl %%d0,(%0)+\n"
 596              "1:\n"
 597              ".section .fixup,\"ax\"\n"
 598              "   .even\n"
 599              "2: addql #4,%2\n"
 600              "   jra 1b\n"
 601              ".previous\n"
 602              ".section __ex_table,\"a\"\n"
 603              "   .align 4\n"
 604              "   .long 21b,2b\n"
 605              "   .long 1b,2b\n"
 606              ".previous"
 607              : "=a"(to), "=a"(from), "=d"(n)
 608              : "0"(to), "1"(from), "2"(0)
 609              : "d0", "memory");
 610         break;
 611     case 8:
 612         __asm__ __volatile__
 613             ("   movel (%1)+,%%d0\n"
 614              "21:movesl %%d0,(%0)+\n"
 615              "1: movel (%1)+,%%d0\n"
 616              "22:movesl %%d0,(%0)+\n"
 617              "2:\n"
 618              ".section .fixup,\"ax\"\n"
 619              "   .even\n"
 620              "3: addql #4,%2\n"
 621              "4: addql #4,%2\n"
 622              "   jra 2b\n"
 623              ".previous\n"
 624              ".section __ex_table,\"a\"\n"
 625              "   .align 4\n"
 626              "   .long 21b,3b\n"
 627              "   .long 1b,3b\n"
 628              "   .long 22b,4b\n"
 629              "   .long 2b,4b\n"
 630              ".previous"
 631              : "=a"(to), "=a"(from), "=d"(n)
 632              : "0"(to), "1"(from), "2"(0)
 633              : "d0", "memory");
 634         break;
 635     case 12:
 636         __asm__ __volatile__
 637             ("   movel (%1)+,%%d0\n"
 638              "21:movesl %%d0,(%0)+\n"
 639              "1: movel (%1)+,%%d0\n"
 640              "22:movesl %%d0,(%0)+\n"
 641              "2: movel (%1)+,%%d0\n"
 642              "23:movesl %%d0,(%0)+\n"
 643              "3:\n"
 644              ".section .fixup,\"ax\"\n"
 645              "   .even\n"
 646              "4: addql #4,%2\n"
 647              "5: addql #4,%2\n"
 648              "6: addql #4,%2\n"
 649              "   jra 3b\n"
 650              ".previous\n"
 651              ".section __ex_table,\"a\"\n"
 652              "   .align 4\n"
 653              "   .long 21b,4b\n"
 654              "   .long 1b,4b\n"
 655              "   .long 22b,5b\n"
 656              "   .long 2b,5b\n"
 657              "   .long 23b,6b\n"
 658              "   .long 3b,6b\n"
 659              ".previous"
 660              : "=a"(to), "=a"(from), "=d"(n)
 661              : "0"(to), "1"(from), "2"(0)
 662              : "d0", "memory");
 663         break;
 664     case 16:
 665         __asm__ __volatile__
 666             ("   movel (%1)+,%%d0\n"
 667              "21:movesl %%d0,(%0)+\n"
 668              "1: movel (%1)+,%%d0\n"
 669              "22:movesl %%d0,(%0)+\n"
 670              "2: movel (%1)+,%%d0\n"
 671              "23:movesl %%d0,(%0)+\n"
 672              "3: movel (%1)+,%%d0\n"
 673              "24:movesl %%d0,(%0)+\n"
 674              "4:"
 675              ".section .fixup,\"ax\"\n"
 676              "   .even\n"
 677              "5: addql #4,%2\n"
 678              "6: addql #4,%2\n"
 679              "7: addql #4,%2\n"
 680              "8: addql #4,%2\n"
 681              "   jra 4b\n"
 682              ".previous\n"
 683              ".section __ex_table,\"a\"\n"
 684              "   .align 4\n"
 685              "   .long 21b,5b\n"
 686              "   .long 1b,5b\n"
 687              "   .long 22b,6b\n"
 688              "   .long 2b,6b\n"
 689              "   .long 23b,7b\n"
 690              "   .long 3b,7b\n"
 691              "   .long 24b,8b\n"
 692              "   .long 4b,8b\n"
 693              ".previous"
 694              : "=a"(to), "=a"(from), "=d"(n)
 695              : "0"(to), "1"(from), "2"(0)
 696              : "d0", "memory");
 697         break;
 698     default:
 699         switch (n & 3) {
 700         case 0:
 701             __copy_to_user_big(to, from, n, "", "");
 702             break;
 703         case 1:
 704             __copy_to_user_big(to, from, n,
 705                                /* fixup */
 706                                "1: addql #1,%2",
 707                                /* copy */
 708                                "   moveb (%1)+,%%d0\n"
 709                                "22:movesb %%d0,(%0)+\n"
 710                                "2:"
 711                                ".section __ex_table,\"a\"\n"
 712                                "   .long 22b,1b\n"
 713                                "   .long 2b,1b\n"
 714                                ".previous");
 715             break;
 716         case 2:
 717             __copy_to_user_big(to, from, n,
 718                                /* fixup */
 719                                "1: addql #2,%2",
 720                                /* copy */
 721                                "   movew (%1)+,%%d0\n"
 722                                "22:movesw %%d0,(%0)+\n"
 723                                "2:"
 724                                ".section __ex_table,\"a\"\n"
 725                                "   .long 22b,1b\n"
 726                                "   .long 2b,1b\n"
 727                                ".previous");
 728             break;
 729         case 3:
 730             __copy_to_user_big(to, from, n,
 731                                /* fixup */
 732                                "1: addql #2,%2\n"
 733                                "2: addql #1,%2",
 734                                /* copy */
 735                                "   movew (%1)+,%%d0\n"
 736                                "23:movesw %%d0,(%0)+\n"
 737                                "3: moveb (%1)+,%%d0\n"
 738                                "24:movesb %%d0,(%0)+\n"
 739                                "4:"
 740                                ".section __ex_table,\"a\"\n"
 741                                "   .long 23b,1b\n"
 742                                "   .long 3b,1b\n"
 743                                "   .long 24b,2b\n"
 744                                "   .long 4b,2b\n"
 745                                ".previous");
 746             break;
 747         }
 748         break;
 749     }
 750     return n;
 751 }
 752
 753 #define copy_from_user(to, from, n)             \
 754 (__builtin_constant_p(n) ?                      \
 755  __constant_copy_from_user(to, from, n) :       \
 756  __generic_copy_from_user(to, from, n))
 757
 758 #define copy_to_user(to, from, n)               \
 759 (__builtin_constant_p(n) ?                      \
 760  __constant_copy_to_user(to, from, n) :         \
 761  __generic_copy_to_user(to, from, n))
 762
 763 #define __copy_from_user(to, from, n) copy_from_user(to, from, n)
 764 #define __copy_to_user(to, from, n) copy_to_user(to, from, n)
 765
 766 /*
 767  * Copy a null terminated string from userspace.
 768  */
 769
 770 static inline long
 771 strncpy_from_user(char *dst, const char __user *src, long count)
 772 {
 773     long res;
 774     if (count == 0) return count;
 775     __asm__ __volatile__
 776         ("1: movesb (%2)+,%%d0\n"
 777          "12:moveb %%d0,(%1)+\n"
 778          "   jeq 2f\n"
 779          "   subql #1,%3\n"
 780          "   jne 1b\n"
 781          "2: subl %3,%0\n"
 782          "3:\n"
 783          ".section .fixup,\"ax\"\n"
 784          "   .even\n"
 785          "4: movel %4,%0\n"
 786          "   jra 3b\n"
 787          ".previous\n"
 788          ".section __ex_table,\"a\"\n"
 789          "   .align 4\n"
 790          "   .long 1b,4b\n"
 791          "   .long 12b,4b\n"
 792          ".previous"
 793          : "=d"(res), "=a"(dst), "=a"(src), "=d"(count)
 794          : "i"(-EFAULT), "0"(count), "1"(dst), "2"(src), "3"(count)
 795          : "d0", "memory");
 796     return res;
 797 }
 798
 799 /*
 800  * Return the size of a string (including the ending 0)
 801  *
 802  * Return 0 on exception, a value greater than N if too long
 803  */
 804 static inline long strnlen_user(const char __user *src, long n)
 805 {
 806         long res;
 807
 808         res = -(unsigned long)src;
 809         __asm__ __volatile__
 810                 ("1:\n"
 811                  "   tstl %2\n"
 812                  "   jeq 3f\n"
 813                  "2: movesb (%1)+,%%d0\n"
 814                  "22:\n"
 815                  "   subql #1,%2\n"
 816                  "   tstb %%d0\n"
 817                  "   jne 1b\n"
 818                  "   jra 4f\n"
 819                  "3:\n"
 820                  "   addql #1,%0\n"
 821                  "4:\n"
 822                  "   addl %1,%0\n"
 823                  "5:\n"
 824                  ".section .fixup,\"ax\"\n"
 825                  "   .even\n"
 826                  "6: moveq %3,%0\n"
 827                  "   jra 5b\n"
 828                  ".previous\n"
 829                  ".section __ex_table,\"a\"\n"
 830                  "   .align 4\n"
 831                  "   .long 2b,6b\n"
 832                  "   .long 22b,6b\n"
 833                  ".previous"
 834                  : "=d"(res), "=a"(src), "=d"(n)
 835                  : "i"(0), "0"(res), "1"(src), "2"(n)
 836                  : "d0");
 837         return res;
 838 }
 839
 840 #define strlen_user(str) strnlen_user(str, 32767)
 841
 842 /*
 843  * Zero Userspace
 844  */
 845
 846 static inline unsigned long
 847 clear_user(void __user *to, unsigned long n)
 848 {
 849     __asm__ __volatile__
 850         ("   tstl %1\n"
 851          "   jeq 3f\n"
 852          "1: movesl %3,(%0)+\n"
 853          "2: subql #1,%1\n"
 854          "   jne 1b\n"
 855          "3: movel %2,%1\n"
 856          "   bclr #1,%1\n"
 857          "   jeq 4f\n"
 858          "24:movesw %3,(%0)+\n"
 859          "4: bclr #0,%1\n"
 860          "   jeq 5f\n"
 861          "25:movesb %3,(%0)+\n"
 862          "5:\n"
 863          ".section .fixup,\"ax\"\n"
 864          "   .even\n"
 865          "61:addql #1,%1\n"
 866          "6: lsll #2,%1\n"
 867          "   addl %2,%1\n"
 868          "   jra 5b\n"
 869          "7: addql #2,%1\n"
 870          "   jra 5b\n"
 871          "8: addql #1,%1\n"
 872          "   jra 5b\n"
 873          ".previous\n"
 874          ".section __ex_table,\"a\"\n"
 875          "   .align 4\n"
 876          "   .long 1b,61b\n"
 877          "   .long 2b,6b\n"
 878          "   .long 3b,61b\n"
 879          "   .long 24b,7b\n"
 880          "   .long 4b,7b\n"
 881          "   .long 25b,8b\n"
 882          "   .long 5b,8b\n"
 883          ".previous"
 884          : "=a"(to), "=d"(n)
 885          : "r"(n & 3), "r"(0), "0"(to), "1"(n/4));
 886     return n;
 887 }
 888
 889 #endif /* _M68K_UACCESS_H */