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