arm-semi.c

   1 /*
   2  *  Arm "Angel" semihosting syscalls
   3  *
   4  *  Copyright (c) 2005, 2007 CodeSourcery.
   5  *  Written by Paul Brook.
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include <stdlib.h>
  26 #include <stdio.h>
  27 #include <time.h>
  28
  29 #include "cpu.h"
  30 #ifdef CONFIG_USER_ONLY
  31 #include "qemu.h"
  32
  33 #define ARM_ANGEL_HEAP_SIZE (128 * 1024 * 1024)
  34 #else
  35 #include "qemu-common.h"
  36 #include "gdbstub.h"
  37 #endif
  38
  39 #define SYS_OPEN        0x01
  40 #define SYS_CLOSE       0x02
  41 #define SYS_WRITEC      0x03
  42 #define SYS_WRITE0      0x04
  43 #define SYS_WRITE       0x05
  44 #define SYS_READ        0x06
  45 #define SYS_READC       0x07
  46 #define SYS_ISTTY       0x09
  47 #define SYS_SEEK        0x0a
  48 #define SYS_FLEN        0x0c
  49 #define SYS_TMPNAM      0x0d
  50 #define SYS_REMOVE      0x0e
  51 #define SYS_RENAME      0x0f
  52 #define SYS_CLOCK       0x10
  53 #define SYS_TIME        0x11
  54 #define SYS_SYSTEM      0x12
  55 #define SYS_ERRNO       0x13
  56 #define SYS_GET_CMDLINE 0x15
  57 #define SYS_HEAPINFO    0x16
  58 #define SYS_EXIT        0x18
  59
  60 #ifndef O_BINARY
  61 #define O_BINARY 0
  62 #endif
  63
  64 #define GDB_O_RDONLY  0x000
  65 #define GDB_O_WRONLY  0x001
  66 #define GDB_O_RDWR    0x002
  67 #define GDB_O_APPEND  0x008
  68 #define GDB_O_CREAT   0x200
  69 #define GDB_O_TRUNC   0x400
  70 #define GDB_O_BINARY  0
  71
  72 static int gdb_open_modeflags[12] = {
  73     GDB_O_RDONLY,
  74     GDB_O_RDONLY | GDB_O_BINARY,
  75     GDB_O_RDWR,
  76     GDB_O_RDWR | GDB_O_BINARY,
  77     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
  78     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
  79     GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
  80     GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
  81     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
  82     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY,
  83     GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
  84     GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY
  85 };
  86
  87 static int open_modeflags[12] = {
  88     O_RDONLY,
  89     O_RDONLY | O_BINARY,
  90     O_RDWR,
  91     O_RDWR | O_BINARY,
  92     O_WRONLY | O_CREAT | O_TRUNC,
  93     O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
  94     O_RDWR | O_CREAT | O_TRUNC,
  95     O_RDWR | O_CREAT | O_TRUNC | O_BINARY,
  96     O_WRONLY | O_CREAT | O_APPEND,
  97     O_WRONLY | O_CREAT | O_APPEND | O_BINARY,
  98     O_RDWR | O_CREAT | O_APPEND,
  99     O_RDWR | O_CREAT | O_APPEND | O_BINARY
 100 };
 101
 102 #ifdef CONFIG_USER_ONLY
 103 static inline uint32_t set_swi_errno(TaskState *ts, uint32_t code)
 104 {
 105     if (code == (uint32_t)-1)
 106         ts->swi_errno = errno;
 107     return code;
 108 }
 109 #else
 110 static inline uint32_t set_swi_errno(CPUState *env, uint32_t code)
 111 {
 112     return code;
 113 }
 114
 115 #include "softmmu-semi.h"
 116 #endif
 117
 118 static target_ulong arm_semi_syscall_len;
 119
 120 #if !defined(CONFIG_USER_ONLY)
 121 static target_ulong syscall_err;
 122 #endif
 123
 124 static void arm_semi_cb(CPUState *env, target_ulong ret, target_ulong err)
 125 {
 126 #ifdef CONFIG_USER_ONLY
 127     TaskState *ts = env->opaque;
 128 #endif
 129
 130     if (ret == (target_ulong)-1) {
 131 #ifdef CONFIG_USER_ONLY
 132         ts->swi_errno = err;
 133 #else
 134         syscall_err = err;
 135 #endif
 136         env->regs[0] = ret;
 137     } else {
 138         /* Fixup syscalls that use nonstardard return conventions.  */
 139         switch (env->regs[0]) {
 140         case SYS_WRITE:
 141         case SYS_READ:
 142             env->regs[0] = arm_semi_syscall_len - ret;
 143             break;
 144         case SYS_SEEK:
 145             env->regs[0] = 0;
 146             break;
 147         default:
 148             env->regs[0] = ret;
 149             break;
 150         }
 151     }
 152 }
 153
 154 static void arm_semi_flen_cb(CPUState *env, target_ulong ret, target_ulong err)
 155 {
 156     /* The size is always stored in big-endian order, extract
 157        the value. We assume the size always fit in 32 bits.  */
 158     uint32_t size;
 159     cpu_memory_rw_debug(env, env->regs[13]-64+32, (uint8_t *)&size, 4, 0);
 160     env->regs[0] = be32_to_cpu(size);
 161 #ifdef CONFIG_USER_ONLY
 162     ((TaskState *)env->opaque)->swi_errno = err;
 163 #else
 164     syscall_err = err;
 165 #endif
 166 }
 167
 168 #define ARG(n)                                  \
 169 ({                                              \
 170     target_ulong __arg;                         \
 171     /* FIXME - handle get_user() failure */     \
 172     get_user_ual(__arg, args + (n) * 4);        \
 173     __arg;                                      \
 174 })
 175 #define SET_ARG(n, val) put_user_ual(val, args + (n) * 4)
 176 uint32_t do_arm_semihosting(CPUState *env)
 177 {
 178     target_ulong args;
 179     char * s;
 180     int nr;
 181     uint32_t ret;
 182     uint32_t len;
 183 #ifdef CONFIG_USER_ONLY
 184     TaskState *ts = env->opaque;
 185 #else
 186     CPUState *ts = env;
 187 #endif
 188
 189     nr = env->regs[0];
 190     args = env->regs[1];
 191     switch (nr) {
 192     case SYS_OPEN:
 193         if (!(s = lock_user_string(ARG(0))))
 194             /* FIXME - should this error code be -TARGET_EFAULT ? */
 195             return (uint32_t)-1;
 196         if (ARG(1) >= 12)
 197             return (uint32_t)-1;
 198         if (strcmp(s, ":tt") == 0) {
 199             if (ARG(1) < 4)
 200                 return STDIN_FILENO;
 201             else
 202                 return STDOUT_FILENO;
 203         }
 204         if (use_gdb_syscalls()) {
 205             gdb_do_syscall(arm_semi_cb, "open,%s,%x,1a4", ARG(0),
 206                            (int)ARG(2)+1, gdb_open_modeflags[ARG(1)]);
 207             return env->regs[0];
 208         } else {
 209             ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644));
 210         }
 211         unlock_user(s, ARG(0), 0);
 212         return ret;
 213     case SYS_CLOSE:
 214         if (use_gdb_syscalls()) {
 215             gdb_do_syscall(arm_semi_cb, "close,%x", ARG(0));
 216             return env->regs[0];
 217         } else {
 218             return set_swi_errno(ts, close(ARG(0)));
 219         }
 220     case SYS_WRITEC:
 221         {
 222           char c;
 223
 224           if (get_user_u8(c, args))
 225               /* FIXME - should this error code be -TARGET_EFAULT ? */
 226               return (uint32_t)-1;
 227           /* Write to debug console.  stderr is near enough.  */
 228           if (use_gdb_syscalls()) {
 229                 gdb_do_syscall(arm_semi_cb, "write,2,%x,1", args);
 230                 return env->regs[0];
 231           } else {
 232                 return write(STDERR_FILENO, &c, 1);
 233           }
 234         }
 235     case SYS_WRITE0:
 236         if (!(s = lock_user_string(args)))
 237             /* FIXME - should this error code be -TARGET_EFAULT ? */
 238             return (uint32_t)-1;
 239         len = strlen(s);
 240         if (use_gdb_syscalls()) {
 241             gdb_do_syscall(arm_semi_cb, "write,2,%x,%x\n", args, len);
 242             ret = env->regs[0];
 243         } else {
 244             ret = write(STDERR_FILENO, s, len);
 245         }
 246         unlock_user(s, args, 0);
 247         return ret;
 248     case SYS_WRITE:
 249         len = ARG(2);
 250         if (use_gdb_syscalls()) {
 251             arm_semi_syscall_len = len;
 252             gdb_do_syscall(arm_semi_cb, "write,%x,%x,%x", ARG(0), ARG(1), len);
 253             return env->regs[0];
 254         } else {
 255             if (!(s = lock_user(VERIFY_READ, ARG(1), len, 1)))
 256                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 257                 return (uint32_t)-1;
 258             ret = set_swi_errno(ts, write(ARG(0), s, len));
 259             unlock_user(s, ARG(1), 0);
 260             if (ret == (uint32_t)-1)
 261                 return -1;
 262             return len - ret;
 263         }
 264     case SYS_READ:
 265         len = ARG(2);
 266         if (use_gdb_syscalls()) {
 267             arm_semi_syscall_len = len;
 268             gdb_do_syscall(arm_semi_cb, "read,%x,%x,%x", ARG(0), ARG(1), len);
 269             return env->regs[0];
 270         } else {
 271             if (!(s = lock_user(VERIFY_WRITE, ARG(1), len, 0)))
 272                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 273                 return (uint32_t)-1;
 274             do
 275               ret = set_swi_errno(ts, read(ARG(0), s, len));
 276             while (ret == -1 && errno == EINTR);
 277             unlock_user(s, ARG(1), len);
 278             if (ret == (uint32_t)-1)
 279                 return -1;
 280             return len - ret;
 281         }
 282     case SYS_READC:
 283        /* XXX: Read from debug cosole. Not implemented.  */
 284         return 0;
 285     case SYS_ISTTY:
 286         if (use_gdb_syscalls()) {
 287             gdb_do_syscall(arm_semi_cb, "isatty,%x", ARG(0));
 288             return env->regs[0];
 289         } else {
 290             return isatty(ARG(0));
 291         }
 292     case SYS_SEEK:
 293         if (use_gdb_syscalls()) {
 294             gdb_do_syscall(arm_semi_cb, "lseek,%x,%x,0", ARG(0), ARG(1));
 295             return env->regs[0];
 296         } else {
 297             ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET));
 298             if (ret == (uint32_t)-1)
 299               return -1;
 300             return 0;
 301         }
 302     case SYS_FLEN:
 303         if (use_gdb_syscalls()) {
 304             gdb_do_syscall(arm_semi_flen_cb, "fstat,%x,%x",
 305                            ARG(0), env->regs[13]-64);
 306             return env->regs[0];
 307         } else {
 308             struct stat buf;
 309             ret = set_swi_errno(ts, fstat(ARG(0), &buf));
 310             if (ret == (uint32_t)-1)
 311                 return -1;
 312             return buf.st_size;
 313         }
 314     case SYS_TMPNAM:
 315         /* XXX: Not implemented.  */
 316         return -1;
 317     case SYS_REMOVE:
 318         if (use_gdb_syscalls()) {
 319             gdb_do_syscall(arm_semi_cb, "unlink,%s", ARG(0), (int)ARG(1)+1);
 320             ret = env->regs[0];
 321         } else {
 322             if (!(s = lock_user_string(ARG(0))))
 323                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 324                 return (uint32_t)-1;
 325             ret =  set_swi_errno(ts, remove(s));
 326             unlock_user(s, ARG(0), 0);
 327         }
 328         return ret;
 329     case SYS_RENAME:
 330         if (use_gdb_syscalls()) {
 331             gdb_do_syscall(arm_semi_cb, "rename,%s,%s",
 332                            ARG(0), (int)ARG(1)+1, ARG(2), (int)ARG(3)+1);
 333             return env->regs[0];
 334         } else {
 335             char *s2;
 336             s = lock_user_string(ARG(0));
 337             s2 = lock_user_string(ARG(2));
 338             if (!s || !s2)
 339                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 340                 ret = (uint32_t)-1;
 341             else
 342                 ret = set_swi_errno(ts, rename(s, s2));
 343             if (s2)
 344                 unlock_user(s2, ARG(2), 0);
 345             if (s)
 346                 unlock_user(s, ARG(0), 0);
 347             return ret;
 348         }
 349     case SYS_CLOCK:
 350         return clock() / (CLOCKS_PER_SEC / 100);
 351     case SYS_TIME:
 352         return set_swi_errno(ts, time(NULL));
 353     case SYS_SYSTEM:
 354         if (use_gdb_syscalls()) {
 355             gdb_do_syscall(arm_semi_cb, "system,%s", ARG(0), (int)ARG(1)+1);
 356             return env->regs[0];
 357         } else {
 358             if (!(s = lock_user_string(ARG(0))))
 359                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 360                 return (uint32_t)-1;
 361             ret = set_swi_errno(ts, system(s));
 362             unlock_user(s, ARG(0), 0);
 363             return ret;
 364         }
 365     case SYS_ERRNO:
 366 #ifdef CONFIG_USER_ONLY
 367         return ts->swi_errno;
 368 #else
 369         return syscall_err;
 370 #endif
 371     case SYS_GET_CMDLINE:
 372 #ifdef CONFIG_USER_ONLY
 373         /* Build a commandline from the original argv.  */
 374         {
 375             char *arm_cmdline_buffer;
 376             const char *host_cmdline_buffer;
 377
 378             unsigned int i;
 379             unsigned int arm_cmdline_len = ARG(1);
 380             unsigned int host_cmdline_len =
 381                 ts->info->arg_end-ts->info->arg_start;
 382
 383             if (!arm_cmdline_len || host_cmdline_len > arm_cmdline_len) {
 384                 return -1; /* not enough space to store command line */
 385             }
 386
 387             if (!host_cmdline_len) {
 388                 /* We special-case the "empty command line" case (argc==0).
 389                    Just provide the terminating 0. */
 390                 arm_cmdline_buffer = lock_user(VERIFY_WRITE, ARG(0), 1, 0);
 391                 arm_cmdline_buffer[0] = 0;
 392                 unlock_user(arm_cmdline_buffer, ARG(0), 1);
 393
 394                 /* Adjust the commandline length argument. */
 395                 SET_ARG(1, 0);
 396                 return 0;
 397             }
 398
 399             /* lock the buffers on the ARM side */
 400             arm_cmdline_buffer =
 401                 lock_user(VERIFY_WRITE, ARG(0), host_cmdline_len, 0);
 402             host_cmdline_buffer =
 403                 lock_user(VERIFY_READ, ts->info->arg_start,
 404                                        host_cmdline_len, 1);
 405
 406             if (arm_cmdline_buffer && host_cmdline_buffer)
 407             {
 408                 /* the last argument is zero-terminated;
 409                    no need for additional termination */
 410                 memcpy(arm_cmdline_buffer, host_cmdline_buffer,
 411                        host_cmdline_len);
 412
 413                 /* separate arguments by white spaces */
 414                 for (i = 0; i < host_cmdline_len-1; i++) {
 415                     if (arm_cmdline_buffer[i] == 0) {
 416                         arm_cmdline_buffer[i] = ' ';
 417                     }
 418                 }
 419
 420                 /* Adjust the commandline length argument. */
 421                 SET_ARG(1, host_cmdline_len-1);
 422             }
 423
 424             /* Unlock the buffers on the ARM side.  */
 425             unlock_user(arm_cmdline_buffer, ARG(0), host_cmdline_len);
 426             unlock_user((void*)host_cmdline_buffer, ts->info->arg_start, 0);
 427
 428             /* Return success if we could return a commandline.  */
 429             return (arm_cmdline_buffer && host_cmdline_buffer) ? 0 : -1;
 430         }
 431 #else
 432         return -1;
 433 #endif
 434     case SYS_HEAPINFO:
 435         {
 436             uint32_t *ptr;
 437             uint32_t limit;
 438
 439 #ifdef CONFIG_USER_ONLY
 440             /* Some C libraries assume the heap immediately follows .bss, so
 441                allocate it using sbrk.  */
 442             if (!ts->heap_limit) {
 443                 long ret;
 444
 445                 ts->heap_base = do_brk(0);
 446                 limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;
 447                 /* Try a big heap, and reduce the size if that fails.  */
 448                 for (;;) {
 449                     ret = do_brk(limit);
 450                     if (ret != -1)
 451                         break;
 452                     limit = (ts->heap_base >> 1) + (limit >> 1);
 453                 }
 454                 ts->heap_limit = limit;
 455             }
 456
 457             if (!(ptr = lock_user(VERIFY_WRITE, ARG(0), 16, 0)))
 458                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 459                 return (uint32_t)-1;
 460             ptr[0] = tswap32(ts->heap_base);
 461             ptr[1] = tswap32(ts->heap_limit);
 462             ptr[2] = tswap32(ts->stack_base);
 463             ptr[3] = tswap32(0); /* Stack limit.  */
 464             unlock_user(ptr, ARG(0), 16);
 465 #else
 466             limit = ram_size;
 467             if (!(ptr = lock_user(VERIFY_WRITE, ARG(0), 16, 0)))
 468                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 469                 return (uint32_t)-1;
 470             /* TODO: Make this use the limit of the loaded application.  */
 471             ptr[0] = tswap32(limit / 2);
 472             ptr[1] = tswap32(limit);
 473             ptr[2] = tswap32(limit); /* Stack base */
 474             ptr[3] = tswap32(0); /* Stack limit.  */
 475             unlock_user(ptr, ARG(0), 16);
 476 #endif
 477             return 0;
 478         }
 479     case SYS_EXIT:
 480         gdb_exit(env, 0);
 481         exit(0);
 482     default:
 483         fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
 484         cpu_dump_state(env, stderr, fprintf, 0);
 485         abort();
 486     }
 487 }