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