target-arm/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 #include "exec/semihost.h"
  31 #ifdef CONFIG_USER_ONLY
  32 #include "qemu.h"
  33
  34 #define ARM_ANGEL_HEAP_SIZE (128 * 1024 * 1024)
  35 #else
  36 #include "qemu-common.h"
  37 #include "exec/gdbstub.h"
  38 #include "hw/arm/arm.h"
  39 #endif
  40
  41 #define TARGET_SYS_OPEN        0x01
  42 #define TARGET_SYS_CLOSE       0x02
  43 #define TARGET_SYS_WRITEC      0x03
  44 #define TARGET_SYS_WRITE0      0x04
  45 #define TARGET_SYS_WRITE       0x05
  46 #define TARGET_SYS_READ        0x06
  47 #define TARGET_SYS_READC       0x07
  48 #define TARGET_SYS_ISTTY       0x09
  49 #define TARGET_SYS_SEEK        0x0a
  50 #define TARGET_SYS_FLEN        0x0c
  51 #define TARGET_SYS_TMPNAM      0x0d
  52 #define TARGET_SYS_REMOVE      0x0e
  53 #define TARGET_SYS_RENAME      0x0f
  54 #define TARGET_SYS_CLOCK       0x10
  55 #define TARGET_SYS_TIME        0x11
  56 #define TARGET_SYS_SYSTEM      0x12
  57 #define TARGET_SYS_ERRNO       0x13
  58 #define TARGET_SYS_GET_CMDLINE 0x15
  59 #define TARGET_SYS_HEAPINFO    0x16
  60 #define TARGET_SYS_EXIT        0x18
  61
  62 /* ADP_Stopped_ApplicationExit is used for exit(0),
  63  * anything else is implemented as exit(1) */
  64 #define ADP_Stopped_ApplicationExit     (0x20026)
  65
  66 #ifndef O_BINARY
  67 #define O_BINARY 0
  68 #endif
  69
  70 #define GDB_O_RDONLY  0x000
  71 #define GDB_O_WRONLY  0x001
  72 #define GDB_O_RDWR    0x002
  73 #define GDB_O_APPEND  0x008
  74 #define GDB_O_CREAT   0x200
  75 #define GDB_O_TRUNC   0x400
  76 #define GDB_O_BINARY  0
  77
  78 static int gdb_open_modeflags[12] = {
  79     GDB_O_RDONLY,
  80     GDB_O_RDONLY | GDB_O_BINARY,
  81     GDB_O_RDWR,
  82     GDB_O_RDWR | GDB_O_BINARY,
  83     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
  84     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
  85     GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
  86     GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
  87     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
  88     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY,
  89     GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
  90     GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY
  91 };
  92
  93 static int open_modeflags[12] = {
  94     O_RDONLY,
  95     O_RDONLY | O_BINARY,
  96     O_RDWR,
  97     O_RDWR | O_BINARY,
  98     O_WRONLY | O_CREAT | O_TRUNC,
  99     O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
 100     O_RDWR | O_CREAT | O_TRUNC,
 101     O_RDWR | O_CREAT | O_TRUNC | O_BINARY,
 102     O_WRONLY | O_CREAT | O_APPEND,
 103     O_WRONLY | O_CREAT | O_APPEND | O_BINARY,
 104     O_RDWR | O_CREAT | O_APPEND,
 105     O_RDWR | O_CREAT | O_APPEND | O_BINARY
 106 };
 107
 108 #ifdef CONFIG_USER_ONLY
 109 static inline uint32_t set_swi_errno(TaskState *ts, uint32_t code)
 110 {
 111     if (code == (uint32_t)-1)
 112         ts->swi_errno = errno;
 113     return code;
 114 }
 115 #else
 116 static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code)
 117 {
 118     return code;
 119 }
 120
 121 #include "exec/softmmu-semi.h"
 122 #endif
 123
 124 static target_ulong arm_semi_syscall_len;
 125
 126 #if !defined(CONFIG_USER_ONLY)
 127 static target_ulong syscall_err;
 128 #endif
 129
 130 static void arm_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
 131 {
 132     ARMCPU *cpu = ARM_CPU(cs);
 133     CPUARMState *env = &cpu->env;
 134 #ifdef CONFIG_USER_ONLY
 135     TaskState *ts = cs->opaque;
 136 #endif
 137
 138     if (ret == (target_ulong)-1) {
 139 #ifdef CONFIG_USER_ONLY
 140         ts->swi_errno = err;
 141 #else
 142         syscall_err = err;
 143 #endif
 144         env->regs[0] = ret;
 145     } else {
 146         /* Fixup syscalls that use nonstardard return conventions.  */
 147         switch (env->regs[0]) {
 148         case TARGET_SYS_WRITE:
 149         case TARGET_SYS_READ:
 150             env->regs[0] = arm_semi_syscall_len - ret;
 151             break;
 152         case TARGET_SYS_SEEK:
 153             env->regs[0] = 0;
 154             break;
 155         default:
 156             env->regs[0] = ret;
 157             break;
 158         }
 159     }
 160 }
 161
 162 static void arm_semi_flen_cb(CPUState *cs, target_ulong ret, target_ulong err)
 163 {
 164     ARMCPU *cpu = ARM_CPU(cs);
 165     CPUARMState *env = &cpu->env;
 166     /* The size is always stored in big-endian order, extract
 167        the value. We assume the size always fit in 32 bits.  */
 168     uint32_t size;
 169     cpu_memory_rw_debug(cs, env->regs[13]-64+32, (uint8_t *)&size, 4, 0);
 170     env->regs[0] = be32_to_cpu(size);
 171 #ifdef CONFIG_USER_ONLY
 172     ((TaskState *)cs->opaque)->swi_errno = err;
 173 #else
 174     syscall_err = err;
 175 #endif
 176 }
 177
 178 /* Read the input value from the argument block; fail the semihosting
 179  * call if the memory read fails.
 180  */
 181 #define GET_ARG(n) do {                                 \
 182     if (get_user_ual(arg ## n, args + (n) * 4)) {       \
 183         return (uint32_t)-1;                            \
 184     }                                                   \
 185 } while (0)
 186
 187 #define SET_ARG(n, val) put_user_ual(val, args + (n) * 4)
 188 uint32_t do_arm_semihosting(CPUARMState *env)
 189 {
 190     ARMCPU *cpu = arm_env_get_cpu(env);
 191     CPUState *cs = CPU(cpu);
 192     target_ulong args;
 193     target_ulong arg0, arg1, arg2, arg3;
 194     char * s;
 195     int nr;
 196     uint32_t ret;
 197     uint32_t len;
 198 #ifdef CONFIG_USER_ONLY
 199     TaskState *ts = cs->opaque;
 200 #else
 201     CPUARMState *ts = env;
 202 #endif
 203
 204     nr = env->regs[0];
 205     args = env->regs[1];
 206     switch (nr) {
 207     case TARGET_SYS_OPEN:
 208         GET_ARG(0);
 209         GET_ARG(1);
 210         GET_ARG(2);
 211         s = lock_user_string(arg0);
 212         if (!s) {
 213             /* FIXME - should this error code be -TARGET_EFAULT ? */
 214             return (uint32_t)-1;
 215         }
 216         if (arg1 >= 12) {
 217             unlock_user(s, arg0, 0);
 218             return (uint32_t)-1;
 219         }
 220         if (strcmp(s, ":tt") == 0) {
 221             int result_fileno = arg1 < 4 ? STDIN_FILENO : STDOUT_FILENO;
 222             unlock_user(s, arg0, 0);
 223             return result_fileno;
 224         }
 225         if (use_gdb_syscalls()) {
 226             gdb_do_syscall(arm_semi_cb, "open,%s,%x,1a4", arg0,
 227                            (int)arg2+1, gdb_open_modeflags[arg1]);
 228             ret = env->regs[0];
 229         } else {
 230             ret = set_swi_errno(ts, open(s, open_modeflags[arg1], 0644));
 231         }
 232         unlock_user(s, arg0, 0);
 233         return ret;
 234     case TARGET_SYS_CLOSE:
 235         GET_ARG(0);
 236         if (use_gdb_syscalls()) {
 237             gdb_do_syscall(arm_semi_cb, "close,%x", arg0);
 238             return env->regs[0];
 239         } else {
 240             return set_swi_errno(ts, close(arg0));
 241         }
 242     case TARGET_SYS_WRITEC:
 243         {
 244           char c;
 245
 246           if (get_user_u8(c, args))
 247               /* FIXME - should this error code be -TARGET_EFAULT ? */
 248               return (uint32_t)-1;
 249           /* Write to debug console.  stderr is near enough.  */
 250           if (use_gdb_syscalls()) {
 251                 gdb_do_syscall(arm_semi_cb, "write,2,%x,1", args);
 252                 return env->regs[0];
 253           } else {
 254                 return write(STDERR_FILENO, &c, 1);
 255           }
 256         }
 257     case TARGET_SYS_WRITE0:
 258         if (!(s = lock_user_string(args)))
 259             /* FIXME - should this error code be -TARGET_EFAULT ? */
 260             return (uint32_t)-1;
 261         len = strlen(s);
 262         if (use_gdb_syscalls()) {
 263             gdb_do_syscall(arm_semi_cb, "write,2,%x,%x\n", args, len);
 264             ret = env->regs[0];
 265         } else {
 266             ret = write(STDERR_FILENO, s, len);
 267         }
 268         unlock_user(s, args, 0);
 269         return ret;
 270     case TARGET_SYS_WRITE:
 271         GET_ARG(0);
 272         GET_ARG(1);
 273         GET_ARG(2);
 274         len = arg2;
 275         if (use_gdb_syscalls()) {
 276             arm_semi_syscall_len = len;
 277             gdb_do_syscall(arm_semi_cb, "write,%x,%x,%x", arg0, arg1, len);
 278             return env->regs[0];
 279         } else {
 280             s = lock_user(VERIFY_READ, arg1, len, 1);
 281             if (!s) {
 282                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 283                 return (uint32_t)-1;
 284             }
 285             ret = set_swi_errno(ts, write(arg0, s, len));
 286             unlock_user(s, arg1, 0);
 287             if (ret == (uint32_t)-1)
 288                 return -1;
 289             return len - ret;
 290         }
 291     case TARGET_SYS_READ:
 292         GET_ARG(0);
 293         GET_ARG(1);
 294         GET_ARG(2);
 295         len = arg2;
 296         if (use_gdb_syscalls()) {
 297             arm_semi_syscall_len = len;
 298             gdb_do_syscall(arm_semi_cb, "read,%x,%x,%x", arg0, arg1, len);
 299             return env->regs[0];
 300         } else {
 301             s = lock_user(VERIFY_WRITE, arg1, len, 0);
 302             if (!s) {
 303                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 304                 return (uint32_t)-1;
 305             }
 306             do {
 307                 ret = set_swi_errno(ts, read(arg0, s, len));
 308             } while (ret == -1 && errno == EINTR);
 309             unlock_user(s, arg1, len);
 310             if (ret == (uint32_t)-1)
 311                 return -1;
 312             return len - ret;
 313         }
 314     case TARGET_SYS_READC:
 315        /* XXX: Read from debug console. Not implemented.  */
 316         return 0;
 317     case TARGET_SYS_ISTTY:
 318         GET_ARG(0);
 319         if (use_gdb_syscalls()) {
 320             gdb_do_syscall(arm_semi_cb, "isatty,%x", arg0);
 321             return env->regs[0];
 322         } else {
 323             return isatty(arg0);
 324         }
 325     case TARGET_SYS_SEEK:
 326         GET_ARG(0);
 327         GET_ARG(1);
 328         if (use_gdb_syscalls()) {
 329             gdb_do_syscall(arm_semi_cb, "lseek,%x,%x,0", arg0, arg1);
 330             return env->regs[0];
 331         } else {
 332             ret = set_swi_errno(ts, lseek(arg0, arg1, SEEK_SET));
 333             if (ret == (uint32_t)-1)
 334               return -1;
 335             return 0;
 336         }
 337     case TARGET_SYS_FLEN:
 338         GET_ARG(0);
 339         if (use_gdb_syscalls()) {
 340             gdb_do_syscall(arm_semi_flen_cb, "fstat,%x,%x",
 341                            arg0, env->regs[13]-64);
 342             return env->regs[0];
 343         } else {
 344             struct stat buf;
 345             ret = set_swi_errno(ts, fstat(arg0, &buf));
 346             if (ret == (uint32_t)-1)
 347                 return -1;
 348             return buf.st_size;
 349         }
 350     case TARGET_SYS_TMPNAM:
 351         /* XXX: Not implemented.  */
 352         return -1;
 353     case TARGET_SYS_REMOVE:
 354         GET_ARG(0);
 355         GET_ARG(1);
 356         if (use_gdb_syscalls()) {
 357             gdb_do_syscall(arm_semi_cb, "unlink,%s", arg0, (int)arg1+1);
 358             ret = env->regs[0];
 359         } else {
 360             s = lock_user_string(arg0);
 361             if (!s) {
 362                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 363                 return (uint32_t)-1;
 364             }
 365             ret =  set_swi_errno(ts, remove(s));
 366             unlock_user(s, arg0, 0);
 367         }
 368         return ret;
 369     case TARGET_SYS_RENAME:
 370         GET_ARG(0);
 371         GET_ARG(1);
 372         GET_ARG(2);
 373         GET_ARG(3);
 374         if (use_gdb_syscalls()) {
 375             gdb_do_syscall(arm_semi_cb, "rename,%s,%s",
 376                            arg0, (int)arg1+1, arg2, (int)arg3+1);
 377             return env->regs[0];
 378         } else {
 379             char *s2;
 380             s = lock_user_string(arg0);
 381             s2 = lock_user_string(arg2);
 382             if (!s || !s2)
 383                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 384                 ret = (uint32_t)-1;
 385             else
 386                 ret = set_swi_errno(ts, rename(s, s2));
 387             if (s2)
 388                 unlock_user(s2, arg2, 0);
 389             if (s)
 390                 unlock_user(s, arg0, 0);
 391             return ret;
 392         }
 393     case TARGET_SYS_CLOCK:
 394         return clock() / (CLOCKS_PER_SEC / 100);
 395     case TARGET_SYS_TIME:
 396         return set_swi_errno(ts, time(NULL));
 397     case TARGET_SYS_SYSTEM:
 398         GET_ARG(0);
 399         GET_ARG(1);
 400         if (use_gdb_syscalls()) {
 401             gdb_do_syscall(arm_semi_cb, "system,%s", arg0, (int)arg1+1);
 402             return env->regs[0];
 403         } else {
 404             s = lock_user_string(arg0);
 405             if (!s) {
 406                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 407                 return (uint32_t)-1;
 408             }
 409             ret = set_swi_errno(ts, system(s));
 410             unlock_user(s, arg0, 0);
 411             return ret;
 412         }
 413     case TARGET_SYS_ERRNO:
 414 #ifdef CONFIG_USER_ONLY
 415         return ts->swi_errno;
 416 #else
 417         return syscall_err;
 418 #endif
 419     case TARGET_SYS_GET_CMDLINE:
 420         {
 421             /* Build a command-line from the original argv.
 422              *
 423              * The inputs are:
 424              *     * arg0, pointer to a buffer of at least the size
 425              *               specified in arg1.
 426              *     * arg1, size of the buffer pointed to by arg0 in
 427              *               bytes.
 428              *
 429              * The outputs are:
 430              *     * arg0, pointer to null-terminated string of the
 431              *               command line.
 432              *     * arg1, length of the string pointed to by arg0.
 433              */
 434
 435             char *output_buffer;
 436             size_t input_size;
 437             size_t output_size;
 438             int status = 0;
 439             GET_ARG(0);
 440             GET_ARG(1);
 441             input_size = arg1;
 442             /* Compute the size of the output string.  */
 443 #if !defined(CONFIG_USER_ONLY)
 444             output_size = strlen(semihosting_get_cmdline()) + 1;
 445 #else
 446             unsigned int i;
 447
 448             output_size = ts->info->arg_end - ts->info->arg_start;
 449             if (!output_size) {
 450                 /* We special-case the "empty command line" case (argc==0).
 451                    Just provide the terminating 0. */
 452                 output_size = 1;
 453             }
 454 #endif
 455
 456             if (output_size > input_size) {
 457                  /* Not enough space to store command-line arguments.  */
 458                 return -1;
 459             }
 460
 461             /* Adjust the command-line length.  */
 462             if (SET_ARG(1, output_size - 1)) {
 463                 /* Couldn't write back to argument block */
 464                 return -1;
 465             }
 466
 467             /* Lock the buffer on the ARM side.  */
 468             output_buffer = lock_user(VERIFY_WRITE, arg0, output_size, 0);
 469             if (!output_buffer) {
 470                 return -1;
 471             }
 472
 473             /* Copy the command-line arguments.  */
 474 #if !defined(CONFIG_USER_ONLY)
 475             pstrcpy(output_buffer, output_size, semihosting_get_cmdline());
 476 #else
 477             if (output_size == 1) {
 478                 /* Empty command-line.  */
 479                 output_buffer[0] = '\0';
 480                 goto out;
 481             }
 482
 483             if (copy_from_user(output_buffer, ts->info->arg_start,
 484                                output_size)) {
 485                 status = -1;
 486                 goto out;
 487             }
 488
 489             /* Separate arguments by white spaces.  */
 490             for (i = 0; i < output_size - 1; i++) {
 491                 if (output_buffer[i] == 0) {
 492                     output_buffer[i] = ' ';
 493                 }
 494             }
 495         out:
 496 #endif
 497             /* Unlock the buffer on the ARM side.  */
 498             unlock_user(output_buffer, arg0, output_size);
 499
 500             return status;
 501         }
 502     case TARGET_SYS_HEAPINFO:
 503         {
 504             uint32_t *ptr;
 505             uint32_t limit;
 506             GET_ARG(0);
 507
 508 #ifdef CONFIG_USER_ONLY
 509             /* Some C libraries assume the heap immediately follows .bss, so
 510                allocate it using sbrk.  */
 511             if (!ts->heap_limit) {
 512                 abi_ulong ret;
 513
 514                 ts->heap_base = do_brk(0);
 515                 limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;
 516                 /* Try a big heap, and reduce the size if that fails.  */
 517                 for (;;) {
 518                     ret = do_brk(limit);
 519                     if (ret >= limit) {
 520                         break;
 521                     }
 522                     limit = (ts->heap_base >> 1) + (limit >> 1);
 523                 }
 524                 ts->heap_limit = limit;
 525             }
 526
 527             ptr = lock_user(VERIFY_WRITE, arg0, 16, 0);
 528             if (!ptr) {
 529                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 530                 return (uint32_t)-1;
 531             }
 532             ptr[0] = tswap32(ts->heap_base);
 533             ptr[1] = tswap32(ts->heap_limit);
 534             ptr[2] = tswap32(ts->stack_base);
 535             ptr[3] = tswap32(0); /* Stack limit.  */
 536             unlock_user(ptr, arg0, 16);
 537 #else
 538             limit = ram_size;
 539             ptr = lock_user(VERIFY_WRITE, arg0, 16, 0);
 540             if (!ptr) {
 541                 /* FIXME - should this error code be -TARGET_EFAULT ? */
 542                 return (uint32_t)-1;
 543             }
 544             /* TODO: Make this use the limit of the loaded application.  */
 545             ptr[0] = tswap32(limit / 2);
 546             ptr[1] = tswap32(limit);
 547             ptr[2] = tswap32(limit); /* Stack base */
 548             ptr[3] = tswap32(0); /* Stack limit.  */
 549             unlock_user(ptr, arg0, 16);
 550 #endif
 551             return 0;
 552         }
 553     case TARGET_SYS_EXIT:
 554         /* ARM specifies only Stopped_ApplicationExit as normal
 555          * exit, everything else is considered an error */
 556         ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1;
 557         gdb_exit(env, ret);
 558         exit(ret);
 559     default:
 560         fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
 561         cpu_dump_state(cs, stderr, fprintf, 0);
 562         abort();
 563     }
 564 }