bsd-user/main.c

   1 /*
   2  *  qemu bsd user main
   3  *
   4  *  Copyright (c) 2003-2008 Fabrice Bellard
   5  *  Copyright (c) 2013-14 Stacey Son
   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/time.h>
  23 #include <sys/resource.h>
  24 #include <sys/sysctl.h>
  25
  26 #include "qemu/osdep.h"
  27 #include "qemu/help-texts.h"
  28 #include "qemu/units.h"
  29 #include "qemu/accel.h"
  30 #include "qemu-version.h"
  31 #include <machine/trap.h>
  32
  33 #include "qapi/error.h"
  34 #include "qemu.h"
  35 #include "qemu/config-file.h"
  36 #include "qemu/error-report.h"
  37 #include "qemu/path.h"
  38 #include "qemu/help_option.h"
  39 #include "qemu/module.h"
  40 #include "exec/exec-all.h"
  41 #include "tcg/tcg.h"
  42 #include "qemu/timer.h"
  43 #include "qemu/envlist.h"
  44 #include "qemu/cutils.h"
  45 #include "exec/log.h"
  46 #include "trace/control.h"
  47 #include "crypto/init.h"
  48 #include "qemu/guest-random.h"
  49
  50 #include "host-os.h"
  51 #include "target_arch_cpu.h"
  52
  53 int singlestep;
  54 uintptr_t guest_base;
  55 bool have_guest_base;
  56 /*
  57  * When running 32-on-64 we should make sure we can fit all of the possible
  58  * guest address space into a contiguous chunk of virtual host memory.
  59  *
  60  * This way we will never overlap with our own libraries or binaries or stack
  61  * or anything else that QEMU maps.
  62  *
  63  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
  64  * of the address for the kernel.  Some cpus rely on this and user space
  65  * uses the high bit(s) for pointer tagging and the like.  For them, we
  66  * must preserve the expected address space.
  67  */
  68 #ifndef MAX_RESERVED_VA
  69 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
  70 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
  71       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
  72 /*
  73  * There are a number of places where we assign reserved_va to a variable
  74  * of type abi_ulong and expect it to fit.  Avoid the last page.
  75  */
  76 #   define MAX_RESERVED_VA  (0xfffffffful & TARGET_PAGE_MASK)
  77 #  else
  78 #   define MAX_RESERVED_VA  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
  79 #  endif
  80 # else
  81 #  define MAX_RESERVED_VA  0
  82 # endif
  83 #endif
  84
  85 /*
  86  * That said, reserving *too* much vm space via mmap can run into problems
  87  * with rlimits, oom due to page table creation, etc.  We will still try it,
  88  * if directed by the command-line option, but not by default.
  89  */
  90 #if HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32
  91 unsigned long reserved_va = MAX_RESERVED_VA;
  92 #else
  93 unsigned long reserved_va;
  94 #endif
  95
  96 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
  97 const char *qemu_uname_release;
  98 char qemu_proc_pathname[PATH_MAX];  /* full path to exeutable */
  99
 100 unsigned long target_maxtsiz = TARGET_MAXTSIZ;   /* max text size */
 101 unsigned long target_dfldsiz = TARGET_DFLDSIZ;   /* initial data size limit */
 102 unsigned long target_maxdsiz = TARGET_MAXDSIZ;   /* max data size */
 103 unsigned long target_dflssiz = TARGET_DFLSSIZ;   /* initial data size limit */
 104 unsigned long target_maxssiz = TARGET_MAXSSIZ;   /* max stack size */
 105 unsigned long target_sgrowsiz = TARGET_SGROWSIZ; /* amount to grow stack */
 106
 107 /* Helper routines for implementing atomic operations. */
 108
 109 void fork_start(void)
 110 {
 111     start_exclusive();
 112     cpu_list_lock();
 113     mmap_fork_start();
 114 }
 115
 116 void fork_end(int child)
 117 {
 118     if (child) {
 119         CPUState *cpu, *next_cpu;
 120         /*
 121          * Child processes created by fork() only have a single thread.  Discard
 122          * information about the parent threads.
 123          */
 124         CPU_FOREACH_SAFE(cpu, next_cpu) {
 125             if (cpu != thread_cpu) {
 126                 QTAILQ_REMOVE_RCU(&cpus, cpu, node);
 127             }
 128         }
 129         mmap_fork_end(child);
 130         /*
 131          * qemu_init_cpu_list() takes care of reinitializing the exclusive
 132          * state, so we don't need to end_exclusive() here.
 133          */
 134         qemu_init_cpu_list();
 135         gdbserver_fork(thread_cpu);
 136     } else {
 137         mmap_fork_end(child);
 138         cpu_list_unlock();
 139         end_exclusive();
 140     }
 141 }
 142
 143 void cpu_loop(CPUArchState *env)
 144 {
 145     target_cpu_loop(env);
 146 }
 147
 148 static void usage(void)
 149 {
 150     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
 151            "\n" QEMU_COPYRIGHT "\n"
 152            "usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 153            "BSD CPU emulator (compiled for %s emulation)\n"
 154            "\n"
 155            "Standard options:\n"
 156            "-h                print this help\n"
 157            "-g port           wait gdb connection to port\n"
 158            "-L path           set the elf interpreter prefix (default=%s)\n"
 159            "-s size           set the stack size in bytes (default=%ld)\n"
 160            "-cpu model        select CPU (-cpu help for list)\n"
 161            "-drop-ld-preload  drop LD_PRELOAD for target process\n"
 162            "-E var=value      sets/modifies targets environment variable(s)\n"
 163            "-U var            unsets targets environment variable(s)\n"
 164            "-B address        set guest_base address to address\n"
 165            "\n"
 166            "Debug options:\n"
 167            "-d item1[,...]    enable logging of specified items\n"
 168            "                  (use '-d help' for a list of log items)\n"
 169            "-D logfile        write logs to 'logfile' (default stderr)\n"
 170            "-singlestep       always run in singlestep mode\n"
 171            "-strace           log system calls\n"
 172            "-trace            [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
 173            "                  specify tracing options\n"
 174            "\n"
 175            "Environment variables:\n"
 176            "QEMU_STRACE       Print system calls and arguments similar to the\n"
 177            "                  'strace' program.  Enable by setting to any value.\n"
 178            "You can use -E and -U options to set/unset environment variables\n"
 179            "for target process.  It is possible to provide several variables\n"
 180            "by repeating the option.  For example:\n"
 181            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 182            "Note that if you provide several changes to single variable\n"
 183            "last change will stay in effect.\n"
 184            "\n"
 185            QEMU_HELP_BOTTOM "\n"
 186            ,
 187            TARGET_NAME,
 188            interp_prefix,
 189            target_dflssiz);
 190     exit(1);
 191 }
 192
 193 __thread CPUState *thread_cpu;
 194
 195 void stop_all_tasks(void)
 196 {
 197     /*
 198      * We trust when using NPTL (pthreads) start_exclusive() handles thread
 199      * stopping correctly.
 200      */
 201     start_exclusive();
 202 }
 203
 204 bool qemu_cpu_is_self(CPUState *cpu)
 205 {
 206     return thread_cpu == cpu;
 207 }
 208
 209 void qemu_cpu_kick(CPUState *cpu)
 210 {
 211     cpu_exit(cpu);
 212 }
 213
 214 /* Assumes contents are already zeroed.  */
 215 static void init_task_state(TaskState *ts)
 216 {
 217     ts->sigaltstack_used = (struct target_sigaltstack) {
 218         .ss_sp = 0,
 219         .ss_size = 0,
 220         .ss_flags = TARGET_SS_DISABLE,
 221     };
 222 }
 223
 224 void gemu_log(const char *fmt, ...)
 225 {
 226     va_list ap;
 227
 228     va_start(ap, fmt);
 229     vfprintf(stderr, fmt, ap);
 230     va_end(ap);
 231 }
 232
 233 static void
 234 adjust_ssize(void)
 235 {
 236     struct rlimit rl;
 237
 238     if (getrlimit(RLIMIT_STACK, &rl) != 0) {
 239         return;
 240     }
 241
 242     target_maxssiz = MIN(target_maxssiz, rl.rlim_max);
 243     target_dflssiz = MIN(MAX(target_dflssiz, rl.rlim_cur), target_maxssiz);
 244
 245     rl.rlim_max = target_maxssiz;
 246     rl.rlim_cur = target_dflssiz;
 247     setrlimit(RLIMIT_STACK, &rl);
 248 }
 249
 250 static void save_proc_pathname(char *argv0)
 251 {
 252     int mib[4];
 253     size_t len;
 254
 255     mib[0] = CTL_KERN;
 256     mib[1] = KERN_PROC;
 257     mib[2] = KERN_PROC_PATHNAME;
 258     mib[3] = -1;
 259
 260     len = sizeof(qemu_proc_pathname);
 261     if (sysctl(mib, 4, qemu_proc_pathname, &len, NULL, 0)) {
 262         perror("sysctl");
 263     }
 264 }
 265
 266 int main(int argc, char **argv)
 267 {
 268     const char *filename;
 269     const char *cpu_model;
 270     const char *cpu_type;
 271     const char *log_file = NULL;
 272     const char *log_mask = NULL;
 273     const char *seed_optarg = NULL;
 274     struct target_pt_regs regs1, *regs = &regs1;
 275     struct image_info info1, *info = &info1;
 276     struct bsd_binprm bprm;
 277     TaskState *ts;
 278     CPUArchState *env;
 279     CPUState *cpu;
 280     int optind, rv;
 281     const char *r;
 282     const char *gdbstub = NULL;
 283     char **target_environ, **wrk;
 284     envlist_t *envlist = NULL;
 285     char *argv0 = NULL;
 286
 287     adjust_ssize();
 288
 289     if (argc <= 1) {
 290         usage();
 291     }
 292
 293     save_proc_pathname(argv[0]);
 294
 295     error_init(argv[0]);
 296     module_call_init(MODULE_INIT_TRACE);
 297     qemu_init_cpu_list();
 298     module_call_init(MODULE_INIT_QOM);
 299
 300     envlist = envlist_create();
 301
 302     /* add current environment into the list */
 303     for (wrk = environ; *wrk != NULL; wrk++) {
 304         (void) envlist_setenv(envlist, *wrk);
 305     }
 306
 307     cpu_model = NULL;
 308
 309     qemu_add_opts(&qemu_trace_opts);
 310
 311     optind = 1;
 312     for (;;) {
 313         if (optind >= argc) {
 314             break;
 315         }
 316         r = argv[optind];
 317         if (r[0] != '-') {
 318             break;
 319         }
 320         optind++;
 321         r++;
 322         if (!strcmp(r, "-")) {
 323             break;
 324         } else if (!strcmp(r, "d")) {
 325             if (optind >= argc) {
 326                 break;
 327             }
 328             log_mask = argv[optind++];
 329         } else if (!strcmp(r, "D")) {
 330             if (optind >= argc) {
 331                 break;
 332             }
 333             log_file = argv[optind++];
 334         } else if (!strcmp(r, "E")) {
 335             r = argv[optind++];
 336             if (envlist_setenv(envlist, r) != 0) {
 337                 usage();
 338             }
 339         } else if (!strcmp(r, "ignore-environment")) {
 340             envlist_free(envlist);
 341             envlist = envlist_create();
 342         } else if (!strcmp(r, "U")) {
 343             r = argv[optind++];
 344             if (envlist_unsetenv(envlist, r) != 0) {
 345                 usage();
 346             }
 347         } else if (!strcmp(r, "s")) {
 348             r = argv[optind++];
 349             rv = qemu_strtoul(r, &r, 0, &target_dflssiz);
 350             if (rv < 0 || target_dflssiz <= 0) {
 351                 usage();
 352             }
 353             if (*r == 'M') {
 354                 target_dflssiz *= 1024 * 1024;
 355             } else if (*r == 'k' || *r == 'K') {
 356                 target_dflssiz *= 1024;
 357             }
 358             if (target_dflssiz > target_maxssiz) {
 359                 usage();
 360             }
 361         } else if (!strcmp(r, "L")) {
 362             interp_prefix = argv[optind++];
 363         } else if (!strcmp(r, "p")) {
 364             qemu_host_page_size = atoi(argv[optind++]);
 365             if (qemu_host_page_size == 0 ||
 366                 (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
 367                 fprintf(stderr, "page size must be a power of two\n");
 368                 exit(1);
 369             }
 370         } else if (!strcmp(r, "g")) {
 371             gdbstub = g_strdup(argv[optind++]);
 372         } else if (!strcmp(r, "r")) {
 373             qemu_uname_release = argv[optind++];
 374         } else if (!strcmp(r, "cpu")) {
 375             cpu_model = argv[optind++];
 376             if (is_help_option(cpu_model)) {
 377                 /* XXX: implement xxx_cpu_list for targets that still miss it */
 378 #if defined(cpu_list)
 379                 cpu_list();
 380 #endif
 381                 exit(1);
 382             }
 383         } else if (!strcmp(r, "B")) {
 384             rv = qemu_strtoul(argv[optind++], NULL, 0, &guest_base);
 385             if (rv < 0) {
 386                 usage();
 387             }
 388             have_guest_base = true;
 389         } else if (!strcmp(r, "drop-ld-preload")) {
 390             (void) envlist_unsetenv(envlist, "LD_PRELOAD");
 391         } else if (!strcmp(r, "seed")) {
 392             seed_optarg = optarg;
 393         } else if (!strcmp(r, "singlestep")) {
 394             singlestep = 1;
 395         } else if (!strcmp(r, "strace")) {
 396             do_strace = 1;
 397         } else if (!strcmp(r, "trace")) {
 398             trace_opt_parse(optarg);
 399         } else if (!strcmp(r, "0")) {
 400             argv0 = argv[optind++];
 401         } else {
 402             usage();
 403         }
 404     }
 405
 406     /* init debug */
 407     {
 408         int mask = 0;
 409         if (log_mask) {
 410             mask = qemu_str_to_log_mask(log_mask);
 411             if (!mask) {
 412                 qemu_print_log_usage(stdout);
 413                 exit(1);
 414             }
 415         }
 416         qemu_set_log_filename_flags(log_file, mask, &error_fatal);
 417     }
 418
 419     if (optind >= argc) {
 420         usage();
 421     }
 422     filename = argv[optind];
 423     if (argv0) {
 424         argv[optind] = argv0;
 425     }
 426
 427     if (!trace_init_backends()) {
 428         exit(1);
 429     }
 430     trace_init_file();
 431
 432     /* Zero out regs */
 433     memset(regs, 0, sizeof(struct target_pt_regs));
 434
 435     /* Zero bsd params */
 436     memset(&bprm, 0, sizeof(bprm));
 437
 438     /* Zero out image_info */
 439     memset(info, 0, sizeof(struct image_info));
 440
 441     /* Scan interp_prefix dir for replacement files. */
 442     init_paths(interp_prefix);
 443
 444     if (cpu_model == NULL) {
 445         cpu_model = TARGET_DEFAULT_CPU_MODEL;
 446     }
 447
 448     cpu_type = parse_cpu_option(cpu_model);
 449
 450     /* init tcg before creating CPUs and to get qemu_host_page_size */
 451     {
 452         AccelClass *ac = ACCEL_GET_CLASS(current_accel());
 453
 454         accel_init_interfaces(ac);
 455         ac->init_machine(NULL);
 456     }
 457     cpu = cpu_create(cpu_type);
 458     env = cpu->env_ptr;
 459     cpu_reset(cpu);
 460     thread_cpu = cpu;
 461
 462     if (getenv("QEMU_STRACE")) {
 463         do_strace = 1;
 464     }
 465
 466     target_environ = envlist_to_environ(envlist, NULL);
 467     envlist_free(envlist);
 468
 469     if (reserved_va) {
 470             mmap_next_start = reserved_va;
 471     }
 472
 473     {
 474         Error *err = NULL;
 475         if (seed_optarg != NULL) {
 476             qemu_guest_random_seed_main(seed_optarg, &err);
 477         } else {
 478             qcrypto_init(&err);
 479         }
 480         if (err) {
 481             error_reportf_err(err, "cannot initialize crypto: ");
 482             exit(1);
 483         }
 484     }
 485
 486     /*
 487      * Now that page sizes are configured we can do
 488      * proper page alignment for guest_base.
 489      */
 490     guest_base = HOST_PAGE_ALIGN(guest_base);
 491
 492     if (loader_exec(filename, argv + optind, target_environ, regs, info,
 493                     &bprm) != 0) {
 494         printf("Error loading %s\n", filename);
 495         _exit(1);
 496     }
 497
 498     for (wrk = target_environ; *wrk; wrk++) {
 499         g_free(*wrk);
 500     }
 501
 502     g_free(target_environ);
 503
 504     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 505         FILE *f = qemu_log_trylock();
 506         if (f) {
 507             fprintf(f, "guest_base  %p\n", (void *)guest_base);
 508             fprintf(f, "page layout changed following binary load\n");
 509             page_dump(f);
 510
 511             fprintf(f, "start_brk   0x" TARGET_ABI_FMT_lx "\n",
 512                     info->start_brk);
 513             fprintf(f, "end_code    0x" TARGET_ABI_FMT_lx "\n",
 514                     info->end_code);
 515             fprintf(f, "start_code  0x" TARGET_ABI_FMT_lx "\n",
 516                     info->start_code);
 517             fprintf(f, "start_data  0x" TARGET_ABI_FMT_lx "\n",
 518                     info->start_data);
 519             fprintf(f, "end_data    0x" TARGET_ABI_FMT_lx "\n",
 520                     info->end_data);
 521             fprintf(f, "start_stack 0x" TARGET_ABI_FMT_lx "\n",
 522                     info->start_stack);
 523             fprintf(f, "brk         0x" TARGET_ABI_FMT_lx "\n", info->brk);
 524             fprintf(f, "entry       0x" TARGET_ABI_FMT_lx "\n", info->entry);
 525
 526             qemu_log_unlock(f);
 527         }
 528     }
 529
 530     /* build Task State */
 531     ts = g_new0(TaskState, 1);
 532     init_task_state(ts);
 533     ts->info = info;
 534     ts->bprm = &bprm;
 535     cpu->opaque = ts;
 536
 537     target_set_brk(info->brk);
 538     syscall_init();
 539     signal_init();
 540
 541     /*
 542      * Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 543      * generating the prologue until now so that the prologue can take
 544      * the real value of GUEST_BASE into account.
 545      */
 546     tcg_prologue_init(tcg_ctx);
 547
 548     target_cpu_init(env, regs);
 549
 550     if (gdbstub) {
 551         gdbserver_start(gdbstub);
 552         gdb_handlesig(cpu, 0);
 553     }
 554     cpu_loop(env);
 555     /* never exits */
 556     return 0;
 557 }