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