linux-user/main.c

   1 /*
   2  *  qemu user main
   3  *
   4  *  Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #include "qemu/osdep.h"
  20 #include "qemu-version.h"
  21 #include <sys/syscall.h>
  22 #include <sys/resource.h>
  23
  24 #include "qapi/error.h"
  25 #include "qemu.h"
  26 #include "qemu/path.h"
  27 #include "qemu/config-file.h"
  28 #include "qemu/cutils.h"
  29 #include "qemu/help_option.h"
  30 #include "cpu.h"
  31 #include "exec/exec-all.h"
  32 #include "tcg.h"
  33 #include "qemu/timer.h"
  34 #include "qemu/envlist.h"
  35 #include "elf.h"
  36 #include "trace/control.h"
  37 #include "target_elf.h"
  38 #include "cpu_loop-common.h"
  39
  40 char *exec_path;
  41
  42 int singlestep;
  43 static const char *filename;
  44 static const char *argv0;
  45 static int gdbstub_port;
  46 static envlist_t *envlist;
  47 static const char *cpu_model;
  48 static const char *cpu_type;
  49 unsigned long mmap_min_addr;
  50 unsigned long guest_base;
  51 int have_guest_base;
  52
  53 /*
  54  * When running 32-on-64 we should make sure we can fit all of the possible
  55  * guest address space into a contiguous chunk of virtual host memory.
  56  *
  57  * This way we will never overlap with our own libraries or binaries or stack
  58  * or anything else that QEMU maps.
  59  *
  60  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
  61  * of the address for the kernel.  Some cpus rely on this and user space
  62  * uses the high bit(s) for pointer tagging and the like.  For them, we
  63  * must preserve the expected address space.
  64  */
  65 #ifndef MAX_RESERVED_VA
  66 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
  67 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
  68       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
  69 /* There are a number of places where we assign reserved_va to a variable
  70    of type abi_ulong and expect it to fit.  Avoid the last page.  */
  71 #   define MAX_RESERVED_VA  (0xfffffffful & TARGET_PAGE_MASK)
  72 #  else
  73 #   define MAX_RESERVED_VA  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
  74 #  endif
  75 # else
  76 #  define MAX_RESERVED_VA  0
  77 # endif
  78 #endif
  79
  80 /* That said, reserving *too* much vm space via mmap can run into problems
  81    with rlimits, oom due to page table creation, etc.  We will still try it,
  82    if directed by the command-line option, but not by default.  */
  83 #if HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32
  84 unsigned long reserved_va = MAX_RESERVED_VA;
  85 #else
  86 unsigned long reserved_va;
  87 #endif
  88
  89 static void usage(int exitcode);
  90
  91 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
  92 const char *qemu_uname_release;
  93
  94 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
  95    we allocate a bigger stack. Need a better solution, for example
  96    by remapping the process stack directly at the right place */
  97 unsigned long guest_stack_size = 8 * 1024 * 1024UL;
  98
  99 void gemu_log(const char *fmt, ...)
 100 {
 101     va_list ap;
 102
 103     va_start(ap, fmt);
 104     vfprintf(stderr, fmt, ap);
 105     va_end(ap);
 106 }
 107
 108 #if defined(TARGET_I386)
 109 int cpu_get_pic_interrupt(CPUX86State *env)
 110 {
 111     return -1;
 112 }
 113 #endif
 114
 115 /***********************************************************/
 116 /* Helper routines for implementing atomic operations.  */
 117
 118 /* Make sure everything is in a consistent state for calling fork().  */
 119 void fork_start(void)
 120 {
 121     start_exclusive();
 122     mmap_fork_start();
 123     cpu_list_lock();
 124 }
 125
 126 void fork_end(int child)
 127 {
 128     mmap_fork_end(child);
 129     if (child) {
 130         CPUState *cpu, *next_cpu;
 131         /* Child processes created by fork() only have a single thread.
 132            Discard information about the parent threads.  */
 133         CPU_FOREACH_SAFE(cpu, next_cpu) {
 134             if (cpu != thread_cpu) {
 135                 QTAILQ_REMOVE(&cpus, cpu, node);
 136             }
 137         }
 138         qemu_init_cpu_list();
 139         gdbserver_fork(thread_cpu);
 140         /* qemu_init_cpu_list() takes care of reinitializing the
 141          * exclusive state, so we don't need to end_exclusive() here.
 142          */
 143     } else {
 144         cpu_list_unlock();
 145         end_exclusive();
 146     }
 147 }
 148
 149 __thread CPUState *thread_cpu;
 150
 151 bool qemu_cpu_is_self(CPUState *cpu)
 152 {
 153     return thread_cpu == cpu;
 154 }
 155
 156 void qemu_cpu_kick(CPUState *cpu)
 157 {
 158     cpu_exit(cpu);
 159 }
 160
 161 void task_settid(TaskState *ts)
 162 {
 163     if (ts->ts_tid == 0) {
 164         ts->ts_tid = (pid_t)syscall(SYS_gettid);
 165     }
 166 }
 167
 168 void stop_all_tasks(void)
 169 {
 170     /*
 171      * We trust that when using NPTL, start_exclusive()
 172      * handles thread stopping correctly.
 173      */
 174     start_exclusive();
 175 }
 176
 177 /* Assumes contents are already zeroed.  */
 178 void init_task_state(TaskState *ts)
 179 {
 180     ts->used = 1;
 181 }
 182
 183 CPUArchState *cpu_copy(CPUArchState *env)
 184 {
 185     CPUState *cpu = ENV_GET_CPU(env);
 186     CPUState *new_cpu = cpu_create(cpu_type);
 187     CPUArchState *new_env = new_cpu->env_ptr;
 188     CPUBreakpoint *bp;
 189     CPUWatchpoint *wp;
 190
 191     /* Reset non arch specific state */
 192     cpu_reset(new_cpu);
 193
 194     memcpy(new_env, env, sizeof(CPUArchState));
 195
 196     /* Clone all break/watchpoints.
 197        Note: Once we support ptrace with hw-debug register access, make sure
 198        BP_CPU break/watchpoints are handled correctly on clone. */
 199     QTAILQ_INIT(&new_cpu->breakpoints);
 200     QTAILQ_INIT(&new_cpu->watchpoints);
 201     QTAILQ_FOREACH(bp, &cpu->breakpoints, entry) {
 202         cpu_breakpoint_insert(new_cpu, bp->pc, bp->flags, NULL);
 203     }
 204     QTAILQ_FOREACH(wp, &cpu->watchpoints, entry) {
 205         cpu_watchpoint_insert(new_cpu, wp->vaddr, wp->len, wp->flags, NULL);
 206     }
 207
 208     return new_env;
 209 }
 210
 211 static void handle_arg_help(const char *arg)
 212 {
 213     usage(EXIT_SUCCESS);
 214 }
 215
 216 static void handle_arg_log(const char *arg)
 217 {
 218     int mask;
 219
 220     mask = qemu_str_to_log_mask(arg);
 221     if (!mask) {
 222         qemu_print_log_usage(stdout);
 223         exit(EXIT_FAILURE);
 224     }
 225     qemu_log_needs_buffers();
 226     qemu_set_log(mask);
 227 }
 228
 229 static void handle_arg_dfilter(const char *arg)
 230 {
 231     qemu_set_dfilter_ranges(arg, NULL);
 232 }
 233
 234 static void handle_arg_log_filename(const char *arg)
 235 {
 236     qemu_set_log_filename(arg, &error_fatal);
 237 }
 238
 239 static void handle_arg_set_env(const char *arg)
 240 {
 241     char *r, *p, *token;
 242     r = p = strdup(arg);
 243     while ((token = strsep(&p, ",")) != NULL) {
 244         if (envlist_setenv(envlist, token) != 0) {
 245             usage(EXIT_FAILURE);
 246         }
 247     }
 248     free(r);
 249 }
 250
 251 static void handle_arg_unset_env(const char *arg)
 252 {
 253     char *r, *p, *token;
 254     r = p = strdup(arg);
 255     while ((token = strsep(&p, ",")) != NULL) {
 256         if (envlist_unsetenv(envlist, token) != 0) {
 257             usage(EXIT_FAILURE);
 258         }
 259     }
 260     free(r);
 261 }
 262
 263 static void handle_arg_argv0(const char *arg)
 264 {
 265     argv0 = strdup(arg);
 266 }
 267
 268 static void handle_arg_stack_size(const char *arg)
 269 {
 270     char *p;
 271     guest_stack_size = strtoul(arg, &p, 0);
 272     if (guest_stack_size == 0) {
 273         usage(EXIT_FAILURE);
 274     }
 275
 276     if (*p == 'M') {
 277         guest_stack_size *= 1024 * 1024;
 278     } else if (*p == 'k' || *p == 'K') {
 279         guest_stack_size *= 1024;
 280     }
 281 }
 282
 283 static void handle_arg_ld_prefix(const char *arg)
 284 {
 285     interp_prefix = strdup(arg);
 286 }
 287
 288 static void handle_arg_pagesize(const char *arg)
 289 {
 290     qemu_host_page_size = atoi(arg);
 291     if (qemu_host_page_size == 0 ||
 292         (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
 293         fprintf(stderr, "page size must be a power of two\n");
 294         exit(EXIT_FAILURE);
 295     }
 296 }
 297
 298 static void handle_arg_randseed(const char *arg)
 299 {
 300     unsigned long long seed;
 301
 302     if (parse_uint_full(arg, &seed, 0) != 0 || seed > UINT_MAX) {
 303         fprintf(stderr, "Invalid seed number: %s\n", arg);
 304         exit(EXIT_FAILURE);
 305     }
 306     srand(seed);
 307 }
 308
 309 static void handle_arg_gdb(const char *arg)
 310 {
 311     gdbstub_port = atoi(arg);
 312 }
 313
 314 static void handle_arg_uname(const char *arg)
 315 {
 316     qemu_uname_release = strdup(arg);
 317 }
 318
 319 static void handle_arg_cpu(const char *arg)
 320 {
 321     cpu_model = strdup(arg);
 322     if (cpu_model == NULL || is_help_option(cpu_model)) {
 323         /* XXX: implement xxx_cpu_list for targets that still miss it */
 324 #if defined(cpu_list)
 325         cpu_list(stdout, &fprintf);
 326 #endif
 327         exit(EXIT_FAILURE);
 328     }
 329 }
 330
 331 static void handle_arg_guest_base(const char *arg)
 332 {
 333     guest_base = strtol(arg, NULL, 0);
 334     have_guest_base = 1;
 335 }
 336
 337 static void handle_arg_reserved_va(const char *arg)
 338 {
 339     char *p;
 340     int shift = 0;
 341     reserved_va = strtoul(arg, &p, 0);
 342     switch (*p) {
 343     case 'k':
 344     case 'K':
 345         shift = 10;
 346         break;
 347     case 'M':
 348         shift = 20;
 349         break;
 350     case 'G':
 351         shift = 30;
 352         break;
 353     }
 354     if (shift) {
 355         unsigned long unshifted = reserved_va;
 356         p++;
 357         reserved_va <<= shift;
 358         if (reserved_va >> shift != unshifted
 359             || (MAX_RESERVED_VA && reserved_va > MAX_RESERVED_VA)) {
 360             fprintf(stderr, "Reserved virtual address too big\n");
 361             exit(EXIT_FAILURE);
 362         }
 363     }
 364     if (*p) {
 365         fprintf(stderr, "Unrecognised -R size suffix '%s'\n", p);
 366         exit(EXIT_FAILURE);
 367     }
 368 }
 369
 370 static void handle_arg_singlestep(const char *arg)
 371 {
 372     singlestep = 1;
 373 }
 374
 375 static void handle_arg_strace(const char *arg)
 376 {
 377     do_strace = 1;
 378 }
 379
 380 static void handle_arg_version(const char *arg)
 381 {
 382     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
 383            "\n" QEMU_COPYRIGHT "\n");
 384     exit(EXIT_SUCCESS);
 385 }
 386
 387 static char *trace_file;
 388 static void handle_arg_trace(const char *arg)
 389 {
 390     g_free(trace_file);
 391     trace_file = trace_opt_parse(arg);
 392 }
 393
 394 struct qemu_argument {
 395     const char *argv;
 396     const char *env;
 397     bool has_arg;
 398     void (*handle_opt)(const char *arg);
 399     const char *example;
 400     const char *help;
 401 };
 402
 403 static const struct qemu_argument arg_table[] = {
 404     {"h",          "",                 false, handle_arg_help,
 405      "",           "print this help"},
 406     {"help",       "",                 false, handle_arg_help,
 407      "",           ""},
 408     {"g",          "QEMU_GDB",         true,  handle_arg_gdb,
 409      "port",       "wait gdb connection to 'port'"},
 410     {"L",          "QEMU_LD_PREFIX",   true,  handle_arg_ld_prefix,
 411      "path",       "set the elf interpreter prefix to 'path'"},
 412     {"s",          "QEMU_STACK_SIZE",  true,  handle_arg_stack_size,
 413      "size",       "set the stack size to 'size' bytes"},
 414     {"cpu",        "QEMU_CPU",         true,  handle_arg_cpu,
 415      "model",      "select CPU (-cpu help for list)"},
 416     {"E",          "QEMU_SET_ENV",     true,  handle_arg_set_env,
 417      "var=value",  "sets targets environment variable (see below)"},
 418     {"U",          "QEMU_UNSET_ENV",   true,  handle_arg_unset_env,
 419      "var",        "unsets targets environment variable (see below)"},
 420     {"0",          "QEMU_ARGV0",       true,  handle_arg_argv0,
 421      "argv0",      "forces target process argv[0] to be 'argv0'"},
 422     {"r",          "QEMU_UNAME",       true,  handle_arg_uname,
 423      "uname",      "set qemu uname release string to 'uname'"},
 424     {"B",          "QEMU_GUEST_BASE",  true,  handle_arg_guest_base,
 425      "address",    "set guest_base address to 'address'"},
 426     {"R",          "QEMU_RESERVED_VA", true,  handle_arg_reserved_va,
 427      "size",       "reserve 'size' bytes for guest virtual address space"},
 428     {"d",          "QEMU_LOG",         true,  handle_arg_log,
 429      "item[,...]", "enable logging of specified items "
 430      "(use '-d help' for a list of items)"},
 431     {"dfilter",    "QEMU_DFILTER",     true,  handle_arg_dfilter,
 432      "range[,...]","filter logging based on address range"},
 433     {"D",          "QEMU_LOG_FILENAME", true, handle_arg_log_filename,
 434      "logfile",     "write logs to 'logfile' (default stderr)"},
 435     {"p",          "QEMU_PAGESIZE",    true,  handle_arg_pagesize,
 436      "pagesize",   "set the host page size to 'pagesize'"},
 437     {"singlestep", "QEMU_SINGLESTEP",  false, handle_arg_singlestep,
 438      "",           "run in singlestep mode"},
 439     {"strace",     "QEMU_STRACE",      false, handle_arg_strace,
 440      "",           "log system calls"},
 441     {"seed",       "QEMU_RAND_SEED",   true,  handle_arg_randseed,
 442      "",           "Seed for pseudo-random number generator"},
 443     {"trace",      "QEMU_TRACE",       true,  handle_arg_trace,
 444      "",           "[[enable=]<pattern>][,events=<file>][,file=<file>]"},
 445     {"version",    "QEMU_VERSION",     false, handle_arg_version,
 446      "",           "display version information and exit"},
 447     {NULL, NULL, false, NULL, NULL, NULL}
 448 };
 449
 450 static void usage(int exitcode)
 451 {
 452     const struct qemu_argument *arginfo;
 453     int maxarglen;
 454     int maxenvlen;
 455
 456     printf("usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 457            "Linux CPU emulator (compiled for " TARGET_NAME " emulation)\n"
 458            "\n"
 459            "Options and associated environment variables:\n"
 460            "\n");
 461
 462     /* Calculate column widths. We must always have at least enough space
 463      * for the column header.
 464      */
 465     maxarglen = strlen("Argument");
 466     maxenvlen = strlen("Env-variable");
 467
 468     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 469         int arglen = strlen(arginfo->argv);
 470         if (arginfo->has_arg) {
 471             arglen += strlen(arginfo->example) + 1;
 472         }
 473         if (strlen(arginfo->env) > maxenvlen) {
 474             maxenvlen = strlen(arginfo->env);
 475         }
 476         if (arglen > maxarglen) {
 477             maxarglen = arglen;
 478         }
 479     }
 480
 481     printf("%-*s %-*s Description\n", maxarglen+1, "Argument",
 482             maxenvlen, "Env-variable");
 483
 484     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 485         if (arginfo->has_arg) {
 486             printf("-%s %-*s %-*s %s\n", arginfo->argv,
 487                    (int)(maxarglen - strlen(arginfo->argv) - 1),
 488                    arginfo->example, maxenvlen, arginfo->env, arginfo->help);
 489         } else {
 490             printf("-%-*s %-*s %s\n", maxarglen, arginfo->argv,
 491                     maxenvlen, arginfo->env,
 492                     arginfo->help);
 493         }
 494     }
 495
 496     printf("\n"
 497            "Defaults:\n"
 498            "QEMU_LD_PREFIX  = %s\n"
 499            "QEMU_STACK_SIZE = %ld byte\n",
 500            interp_prefix,
 501            guest_stack_size);
 502
 503     printf("\n"
 504            "You can use -E and -U options or the QEMU_SET_ENV and\n"
 505            "QEMU_UNSET_ENV environment variables to set and unset\n"
 506            "environment variables for the target process.\n"
 507            "It is possible to provide several variables by separating them\n"
 508            "by commas in getsubopt(3) style. Additionally it is possible to\n"
 509            "provide the -E and -U options multiple times.\n"
 510            "The following lines are equivalent:\n"
 511            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 512            "    -E var1=val2,var2=val2 -U LD_PRELOAD,LD_DEBUG\n"
 513            "    QEMU_SET_ENV=var1=val2,var2=val2 QEMU_UNSET_ENV=LD_PRELOAD,LD_DEBUG\n"
 514            "Note that if you provide several changes to a single variable\n"
 515            "the last change will stay in effect.\n"
 516            "\n"
 517            QEMU_HELP_BOTTOM "\n");
 518
 519     exit(exitcode);
 520 }
 521
 522 static int parse_args(int argc, char **argv)
 523 {
 524     const char *r;
 525     int optind;
 526     const struct qemu_argument *arginfo;
 527
 528     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 529         if (arginfo->env == NULL) {
 530             continue;
 531         }
 532
 533         r = getenv(arginfo->env);
 534         if (r != NULL) {
 535             arginfo->handle_opt(r);
 536         }
 537     }
 538
 539     optind = 1;
 540     for (;;) {
 541         if (optind >= argc) {
 542             break;
 543         }
 544         r = argv[optind];
 545         if (r[0] != '-') {
 546             break;
 547         }
 548         optind++;
 549         r++;
 550         if (!strcmp(r, "-")) {
 551             break;
 552         }
 553         /* Treat --foo the same as -foo.  */
 554         if (r[0] == '-') {
 555             r++;
 556         }
 557
 558         for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
 559             if (!strcmp(r, arginfo->argv)) {
 560                 if (arginfo->has_arg) {
 561                     if (optind >= argc) {
 562                         (void) fprintf(stderr,
 563                             "qemu: missing argument for option '%s'\n", r);
 564                         exit(EXIT_FAILURE);
 565                     }
 566                     arginfo->handle_opt(argv[optind]);
 567                     optind++;
 568                 } else {
 569                     arginfo->handle_opt(NULL);
 570                 }
 571                 break;
 572             }
 573         }
 574
 575         /* no option matched the current argv */
 576         if (arginfo->handle_opt == NULL) {
 577             (void) fprintf(stderr, "qemu: unknown option '%s'\n", r);
 578             exit(EXIT_FAILURE);
 579         }
 580     }
 581
 582     if (optind >= argc) {
 583         (void) fprintf(stderr, "qemu: no user program specified\n");
 584         exit(EXIT_FAILURE);
 585     }
 586
 587     filename = argv[optind];
 588     exec_path = argv[optind];
 589
 590     return optind;
 591 }
 592
 593 int main(int argc, char **argv, char **envp)
 594 {
 595     struct target_pt_regs regs1, *regs = &regs1;
 596     struct image_info info1, *info = &info1;
 597     struct linux_binprm bprm;
 598     TaskState *ts;
 599     CPUArchState *env;
 600     CPUState *cpu;
 601     int optind;
 602     char **target_environ, **wrk;
 603     char **target_argv;
 604     int target_argc;
 605     int i;
 606     int ret;
 607     int execfd;
 608
 609     module_call_init(MODULE_INIT_TRACE);
 610     qemu_init_cpu_list();
 611     module_call_init(MODULE_INIT_QOM);
 612
 613     envlist = envlist_create();
 614
 615     /* add current environment into the list */
 616     for (wrk = environ; *wrk != NULL; wrk++) {
 617         (void) envlist_setenv(envlist, *wrk);
 618     }
 619
 620     /* Read the stack limit from the kernel.  If it's "unlimited",
 621        then we can do little else besides use the default.  */
 622     {
 623         struct rlimit lim;
 624         if (getrlimit(RLIMIT_STACK, &lim) == 0
 625             && lim.rlim_cur != RLIM_INFINITY
 626             && lim.rlim_cur == (target_long)lim.rlim_cur) {
 627             guest_stack_size = lim.rlim_cur;
 628         }
 629     }
 630
 631     cpu_model = NULL;
 632
 633     srand(time(NULL));
 634
 635     qemu_add_opts(&qemu_trace_opts);
 636
 637     optind = parse_args(argc, argv);
 638
 639     if (!trace_init_backends()) {
 640         exit(1);
 641     }
 642     trace_init_file(trace_file);
 643
 644     /* Zero out regs */
 645     memset(regs, 0, sizeof(struct target_pt_regs));
 646
 647     /* Zero out image_info */
 648     memset(info, 0, sizeof(struct image_info));
 649
 650     memset(&bprm, 0, sizeof (bprm));
 651
 652     /* Scan interp_prefix dir for replacement files. */
 653     init_paths(interp_prefix);
 654
 655     init_qemu_uname_release();
 656
 657     execfd = qemu_getauxval(AT_EXECFD);
 658     if (execfd == 0) {
 659         execfd = open(filename, O_RDONLY);
 660         if (execfd < 0) {
 661             printf("Error while loading %s: %s\n", filename, strerror(errno));
 662             _exit(EXIT_FAILURE);
 663         }
 664     }
 665
 666     if (cpu_model == NULL) {
 667         cpu_model = cpu_get_model(get_elf_eflags(execfd));
 668     }
 669     cpu_type = parse_cpu_model(cpu_model);
 670
 671     /* init tcg before creating CPUs and to get qemu_host_page_size */
 672     tcg_exec_init(0);
 673
 674     cpu = cpu_create(cpu_type);
 675     env = cpu->env_ptr;
 676     cpu_reset(cpu);
 677
 678     thread_cpu = cpu;
 679
 680     if (getenv("QEMU_STRACE")) {
 681         do_strace = 1;
 682     }
 683
 684     if (getenv("QEMU_RAND_SEED")) {
 685         handle_arg_randseed(getenv("QEMU_RAND_SEED"));
 686     }
 687
 688     target_environ = envlist_to_environ(envlist, NULL);
 689     envlist_free(envlist);
 690
 691     /*
 692      * Now that page sizes are configured in tcg_exec_init() we can do
 693      * proper page alignment for guest_base.
 694      */
 695     guest_base = HOST_PAGE_ALIGN(guest_base);
 696
 697     if (reserved_va || have_guest_base) {
 698         guest_base = init_guest_space(guest_base, reserved_va, 0,
 699                                       have_guest_base);
 700         if (guest_base == (unsigned long)-1) {
 701             fprintf(stderr, "Unable to reserve 0x%lx bytes of virtual address "
 702                     "space for use as guest address space (check your virtual "
 703                     "memory ulimit setting or reserve less using -R option)\n",
 704                     reserved_va);
 705             exit(EXIT_FAILURE);
 706         }
 707
 708         if (reserved_va) {
 709             mmap_next_start = reserved_va;
 710         }
 711     }
 712
 713     /*
 714      * Read in mmap_min_addr kernel parameter.  This value is used
 715      * When loading the ELF image to determine whether guest_base
 716      * is needed.  It is also used in mmap_find_vma.
 717      */
 718     {
 719         FILE *fp;
 720
 721         if ((fp = fopen("/proc/sys/vm/mmap_min_addr", "r")) != NULL) {
 722             unsigned long tmp;
 723             if (fscanf(fp, "%lu", &tmp) == 1) {
 724                 mmap_min_addr = tmp;
 725                 qemu_log_mask(CPU_LOG_PAGE, "host mmap_min_addr=0x%lx\n", mmap_min_addr);
 726             }
 727             fclose(fp);
 728         }
 729     }
 730
 731     /*
 732      * Prepare copy of argv vector for target.
 733      */
 734     target_argc = argc - optind;
 735     target_argv = calloc(target_argc + 1, sizeof (char *));
 736     if (target_argv == NULL) {
 737         (void) fprintf(stderr, "Unable to allocate memory for target_argv\n");
 738         exit(EXIT_FAILURE);
 739     }
 740
 741     /*
 742      * If argv0 is specified (using '-0' switch) we replace
 743      * argv[0] pointer with the given one.
 744      */
 745     i = 0;
 746     if (argv0 != NULL) {
 747         target_argv[i++] = strdup(argv0);
 748     }
 749     for (; i < target_argc; i++) {
 750         target_argv[i] = strdup(argv[optind + i]);
 751     }
 752     target_argv[target_argc] = NULL;
 753
 754     ts = g_new0(TaskState, 1);
 755     init_task_state(ts);
 756     /* build Task State */
 757     ts->info = info;
 758     ts->bprm = &bprm;
 759     cpu->opaque = ts;
 760     task_settid(ts);
 761
 762     ret = loader_exec(execfd, filename, target_argv, target_environ, regs,
 763         info, &bprm);
 764     if (ret != 0) {
 765         printf("Error while loading %s: %s\n", filename, strerror(-ret));
 766         _exit(EXIT_FAILURE);
 767     }
 768
 769     for (wrk = target_environ; *wrk; wrk++) {
 770         g_free(*wrk);
 771     }
 772
 773     g_free(target_environ);
 774
 775     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 776         qemu_log("guest_base  0x%lx\n", guest_base);
 777         log_page_dump();
 778
 779         qemu_log("start_brk   0x" TARGET_ABI_FMT_lx "\n", info->start_brk);
 780         qemu_log("end_code    0x" TARGET_ABI_FMT_lx "\n", info->end_code);
 781         qemu_log("start_code  0x" TARGET_ABI_FMT_lx "\n", info->start_code);
 782         qemu_log("start_data  0x" TARGET_ABI_FMT_lx "\n", info->start_data);
 783         qemu_log("end_data    0x" TARGET_ABI_FMT_lx "\n", info->end_data);
 784         qemu_log("start_stack 0x" TARGET_ABI_FMT_lx "\n", info->start_stack);
 785         qemu_log("brk         0x" TARGET_ABI_FMT_lx "\n", info->brk);
 786         qemu_log("entry       0x" TARGET_ABI_FMT_lx "\n", info->entry);
 787         qemu_log("argv_start  0x" TARGET_ABI_FMT_lx "\n", info->arg_start);
 788         qemu_log("env_start   0x" TARGET_ABI_FMT_lx "\n",
 789                  info->arg_end + (abi_ulong)sizeof(abi_ulong));
 790         qemu_log("auxv_start  0x" TARGET_ABI_FMT_lx "\n", info->saved_auxv);
 791     }
 792
 793     target_set_brk(info->brk);
 794     syscall_init();
 795     signal_init();
 796
 797     /* Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 798        generating the prologue until now so that the prologue can take
 799        the real value of GUEST_BASE into account.  */
 800     tcg_prologue_init(tcg_ctx);
 801     tcg_region_init();
 802
 803     target_cpu_copy_regs(env, regs);
 804
 805     if (gdbstub_port) {
 806         if (gdbserver_start(gdbstub_port) < 0) {
 807             fprintf(stderr, "qemu: could not open gdbserver on port %d\n",
 808                     gdbstub_port);
 809             exit(EXIT_FAILURE);
 810         }
 811         gdb_handlesig(cpu, 0);
 812     }
 813     cpu_loop(env);
 814     /* never exits */
 815     return 0;
 816 }