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