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-common.h"
  28 #include "qemu/units.h"
  29 #include "qemu/accel.h"
  30 #include "sysemu/tcg.h"
  31 #include "qemu-version.h"
  32 #include <machine/trap.h>
  33
  34 #include "qapi/error.h"
  35 #include "qemu.h"
  36 #include "qemu/config-file.h"
  37 #include "qemu/error-report.h"
  38 #include "qemu/path.h"
  39 #include "qemu/help_option.h"
  40 #include "qemu/module.h"
  41 #include "exec/exec-all.h"
  42 #include "tcg/tcg.h"
  43 #include "qemu/timer.h"
  44 #include "qemu/envlist.h"
  45 #include "qemu/cutils.h"
  46 #include "exec/log.h"
  47 #include "trace/control.h"
  48 #include "crypto/init.h"
  49 #include "qemu/guest-random.h"
  50
  51 #include "host-os.h"
  52 #include "target_arch_cpu.h"
  53
  54 int singlestep;
  55 uintptr_t guest_base;
  56 bool have_guest_base;
  57 /*
  58  * When running 32-on-64 we should make sure we can fit all of the possible
  59  * guest address space into a contiguous chunk of virtual host memory.
  60  *
  61  * This way we will never overlap with our own libraries or binaries or stack
  62  * or anything else that QEMU maps.
  63  *
  64  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
  65  * of the address for the kernel.  Some cpus rely on this and user space
  66  * uses the high bit(s) for pointer tagging and the like.  For them, we
  67  * must preserve the expected address space.
  68  */
  69 #ifndef MAX_RESERVED_VA
  70 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
  71 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
  72       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
  73 /*
  74  * There are a number of places where we assign reserved_va to a variable
  75  * of type abi_ulong and expect it to fit.  Avoid the last page.
  76  */
  77 #   define MAX_RESERVED_VA  (0xfffffffful & TARGET_PAGE_MASK)
  78 #  else
  79 #   define MAX_RESERVED_VA  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
  80 #  endif
  81 # else
  82 #  define MAX_RESERVED_VA  0
  83 # endif
  84 #endif
  85
  86 /*
  87  * That said, reserving *too* much vm space via mmap can run into problems
  88  * with rlimits, oom due to page table creation, etc.  We will still try it,
  89  * if directed by the command-line option, but not by default.
  90  */
  91 #if HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32
  92 unsigned long reserved_va = MAX_RESERVED_VA;
  93 #else
  94 unsigned long reserved_va;
  95 #endif
  96
  97 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
  98 const char *qemu_uname_release;
  99 enum BSDType bsd_type;
 100 char qemu_proc_pathname[PATH_MAX];  /* full path to exeutable */
 101
 102 unsigned long target_maxtsiz = TARGET_MAXTSIZ;   /* max text size */
 103 unsigned long target_dfldsiz = TARGET_DFLDSIZ;   /* initial data size limit */
 104 unsigned long target_maxdsiz = TARGET_MAXDSIZ;   /* max data size */
 105 unsigned long target_dflssiz = TARGET_DFLSSIZ;   /* initial data size limit */
 106 unsigned long target_maxssiz = TARGET_MAXSSIZ;   /* max stack size */
 107 unsigned long target_sgrowsiz = TARGET_SGROWSIZ; /* amount to grow stack */
 108
 109 /* Helper routines for implementing atomic operations. */
 110
 111 void fork_start(void)
 112 {
 113     start_exclusive();
 114     cpu_list_lock();
 115     mmap_fork_start();
 116 }
 117
 118 void fork_end(int child)
 119 {
 120     if (child) {
 121         CPUState *cpu, *next_cpu;
 122         /*
 123          * Child processes created by fork() only have a single thread.  Discard
 124          * information about the parent threads.
 125          */
 126         CPU_FOREACH_SAFE(cpu, next_cpu) {
 127             if (cpu != thread_cpu) {
 128                 QTAILQ_REMOVE_RCU(&cpus, cpu, node);
 129             }
 130         }
 131         mmap_fork_end(child);
 132         /*
 133          * qemu_init_cpu_list() takes care of reinitializing the exclusive
 134          * state, so we don't need to end_exclusive() here.
 135          */
 136         qemu_init_cpu_list();
 137         gdbserver_fork(thread_cpu);
 138     } else {
 139         mmap_fork_end(child);
 140         cpu_list_unlock();
 141         end_exclusive();
 142     }
 143 }
 144
 145 void cpu_loop(CPUArchState *env)
 146 {
 147     target_cpu_loop(env);
 148 }
 149
 150 static void usage(void)
 151 {
 152     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
 153            "\n" QEMU_COPYRIGHT "\n"
 154            "usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
 155            "BSD CPU emulator (compiled for %s emulation)\n"
 156            "\n"
 157            "Standard options:\n"
 158            "-h                print this help\n"
 159            "-g port           wait gdb connection to port\n"
 160            "-L path           set the elf interpreter prefix (default=%s)\n"
 161            "-s size           set the stack size in bytes (default=%ld)\n"
 162            "-cpu model        select CPU (-cpu help for list)\n"
 163            "-drop-ld-preload  drop LD_PRELOAD for target process\n"
 164            "-E var=value      sets/modifies targets environment variable(s)\n"
 165            "-U var            unsets targets environment variable(s)\n"
 166            "-B address        set guest_base address to address\n"
 167            "-bsd type         select emulated BSD type FreeBSD/NetBSD/OpenBSD (default)\n"
 168            "\n"
 169            "Debug options:\n"
 170            "-d item1[,...]    enable logging of specified items\n"
 171            "                  (use '-d help' for a list of log items)\n"
 172            "-D logfile        write logs to 'logfile' (default stderr)\n"
 173            "-singlestep       always run in singlestep mode\n"
 174            "-strace           log system calls\n"
 175            "-trace            [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
 176            "                  specify tracing options\n"
 177            "\n"
 178            "Environment variables:\n"
 179            "QEMU_STRACE       Print system calls and arguments similar to the\n"
 180            "                  'strace' program.  Enable by setting to any value.\n"
 181            "You can use -E and -U options to set/unset environment variables\n"
 182            "for target process.  It is possible to provide several variables\n"
 183            "by repeating the option.  For example:\n"
 184            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
 185            "Note that if you provide several changes to single variable\n"
 186            "last change will stay in effect.\n"
 187            "\n"
 188            QEMU_HELP_BOTTOM "\n"
 189            ,
 190            TARGET_NAME,
 191            interp_prefix,
 192            target_dflssiz);
 193     exit(1);
 194 }
 195
 196 __thread CPUState *thread_cpu;
 197
 198 void stop_all_tasks(void)
 199 {
 200     /*
 201      * We trust when using NPTL (pthreads) start_exclusive() handles thread
 202      * stopping correctly.
 203      */
 204     start_exclusive();
 205 }
 206
 207 bool qemu_cpu_is_self(CPUState *cpu)
 208 {
 209     return thread_cpu == cpu;
 210 }
 211
 212 void qemu_cpu_kick(CPUState *cpu)
 213 {
 214     cpu_exit(cpu);
 215 }
 216
 217 /* Assumes contents are already zeroed.  */
 218 static void init_task_state(TaskState *ts)
 219 {
 220     ts->sigaltstack_used = (struct target_sigaltstack) {
 221         .ss_sp = 0,
 222         .ss_size = 0,
 223         .ss_flags = TARGET_SS_DISABLE,
 224     };
 225 }
 226
 227 void gemu_log(const char *fmt, ...)
 228 {
 229     va_list ap;
 230
 231     va_start(ap, fmt);
 232     vfprintf(stderr, fmt, ap);
 233     va_end(ap);
 234 }
 235
 236 static void
 237 adjust_ssize(void)
 238 {
 239     struct rlimit rl;
 240
 241     if (getrlimit(RLIMIT_STACK, &rl) != 0) {
 242         return;
 243     }
 244
 245     target_maxssiz = MIN(target_maxssiz, rl.rlim_max);
 246     target_dflssiz = MIN(MAX(target_dflssiz, rl.rlim_cur), target_maxssiz);
 247
 248     rl.rlim_max = target_maxssiz;
 249     rl.rlim_cur = target_dflssiz;
 250     setrlimit(RLIMIT_STACK, &rl);
 251 }
 252
 253 static void save_proc_pathname(char *argv0)
 254 {
 255     int mib[4];
 256     size_t len;
 257
 258     mib[0] = CTL_KERN;
 259     mib[1] = KERN_PROC;
 260     mib[2] = KERN_PROC_PATHNAME;
 261     mib[3] = -1;
 262
 263     len = sizeof(qemu_proc_pathname);
 264     if (sysctl(mib, 4, qemu_proc_pathname, &len, NULL, 0)) {
 265         perror("sysctl");
 266     }
 267 }
 268
 269 int main(int argc, char **argv)
 270 {
 271     const char *filename;
 272     const char *cpu_model;
 273     const char *cpu_type;
 274     const char *log_file = NULL;
 275     const char *log_mask = NULL;
 276     const char *seed_optarg = NULL;
 277     struct target_pt_regs regs1, *regs = &regs1;
 278     struct image_info info1, *info = &info1;
 279     struct bsd_binprm bprm;
 280     TaskState *ts;
 281     CPUArchState *env;
 282     CPUState *cpu;
 283     int optind, rv;
 284     const char *r;
 285     const char *gdbstub = NULL;
 286     char **target_environ, **wrk;
 287     envlist_t *envlist = NULL;
 288     bsd_type = HOST_DEFAULT_BSD_TYPE;
 289     char *argv0 = NULL;
 290
 291     adjust_ssize();
 292
 293     if (argc <= 1) {
 294         usage();
 295     }
 296
 297     save_proc_pathname(argv[0]);
 298
 299     error_init(argv[0]);
 300     module_call_init(MODULE_INIT_TRACE);
 301     qemu_init_cpu_list();
 302     module_call_init(MODULE_INIT_QOM);
 303
 304     envlist = envlist_create();
 305
 306     /* add current environment into the list */
 307     for (wrk = environ; *wrk != NULL; wrk++) {
 308         (void) envlist_setenv(envlist, *wrk);
 309     }
 310
 311     cpu_model = NULL;
 312
 313     qemu_add_opts(&qemu_trace_opts);
 314
 315     optind = 1;
 316     for (;;) {
 317         if (optind >= argc) {
 318             break;
 319         }
 320         r = argv[optind];
 321         if (r[0] != '-') {
 322             break;
 323         }
 324         optind++;
 325         r++;
 326         if (!strcmp(r, "-")) {
 327             break;
 328         } else if (!strcmp(r, "d")) {
 329             if (optind >= argc) {
 330                 break;
 331             }
 332             log_mask = argv[optind++];
 333         } else if (!strcmp(r, "D")) {
 334             if (optind >= argc) {
 335                 break;
 336             }
 337             log_file = argv[optind++];
 338         } else if (!strcmp(r, "E")) {
 339             r = argv[optind++];
 340             if (envlist_setenv(envlist, r) != 0) {
 341                 usage();
 342             }
 343         } else if (!strcmp(r, "ignore-environment")) {
 344             envlist_free(envlist);
 345             envlist = envlist_create();
 346         } else if (!strcmp(r, "U")) {
 347             r = argv[optind++];
 348             if (envlist_unsetenv(envlist, r) != 0) {
 349                 usage();
 350             }
 351         } else if (!strcmp(r, "s")) {
 352             r = argv[optind++];
 353             rv = qemu_strtoul(r, &r, 0, &target_dflssiz);
 354             if (rv < 0 || target_dflssiz <= 0) {
 355                 usage();
 356             }
 357             if (*r == 'M') {
 358                 target_dflssiz *= 1024 * 1024;
 359             } else if (*r == 'k' || *r == 'K') {
 360                 target_dflssiz *= 1024;
 361             }
 362             if (target_dflssiz > target_maxssiz) {
 363                 usage();
 364             }
 365         } else if (!strcmp(r, "L")) {
 366             interp_prefix = argv[optind++];
 367         } else if (!strcmp(r, "p")) {
 368             qemu_host_page_size = atoi(argv[optind++]);
 369             if (qemu_host_page_size == 0 ||
 370                 (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
 371                 fprintf(stderr, "page size must be a power of two\n");
 372                 exit(1);
 373             }
 374         } else if (!strcmp(r, "g")) {
 375             gdbstub = g_strdup(argv[optind++]);
 376         } else if (!strcmp(r, "r")) {
 377             qemu_uname_release = argv[optind++];
 378         } else if (!strcmp(r, "cpu")) {
 379             cpu_model = argv[optind++];
 380             if (is_help_option(cpu_model)) {
 381                 /* XXX: implement xxx_cpu_list for targets that still miss it */
 382 #if defined(cpu_list)
 383                 cpu_list();
 384 #endif
 385                 exit(1);
 386             }
 387         } else if (!strcmp(r, "B")) {
 388             rv = qemu_strtoul(argv[optind++], NULL, 0, &guest_base);
 389             if (rv < 0) {
 390                 usage();
 391             }
 392             have_guest_base = true;
 393         } else if (!strcmp(r, "drop-ld-preload")) {
 394             (void) envlist_unsetenv(envlist, "LD_PRELOAD");
 395         } else if (!strcmp(r, "bsd")) {
 396             if (!strcasecmp(argv[optind], "freebsd")) {
 397                 bsd_type = target_freebsd;
 398             } else if (!strcasecmp(argv[optind], "netbsd")) {
 399                 bsd_type = target_netbsd;
 400             } else if (!strcasecmp(argv[optind], "openbsd")) {
 401                 bsd_type = target_openbsd;
 402             } else {
 403                 usage();
 404             }
 405             optind++;
 406         } else if (!strcmp(r, "seed")) {
 407             seed_optarg = optarg;
 408         } else if (!strcmp(r, "singlestep")) {
 409             singlestep = 1;
 410         } else if (!strcmp(r, "strace")) {
 411             do_strace = 1;
 412         } else if (!strcmp(r, "trace")) {
 413             trace_opt_parse(optarg);
 414         } else if (!strcmp(r, "0")) {
 415             argv0 = argv[optind++];
 416         } else {
 417             usage();
 418         }
 419     }
 420
 421     /* init debug */
 422     qemu_log_needs_buffers();
 423     qemu_set_log_filename(log_file, &error_fatal);
 424     if (log_mask) {
 425         int mask;
 426
 427         mask = qemu_str_to_log_mask(log_mask);
 428         if (!mask) {
 429             qemu_print_log_usage(stdout);
 430             exit(1);
 431         }
 432         qemu_set_log(mask);
 433     }
 434
 435     if (optind >= argc) {
 436         usage();
 437     }
 438     filename = argv[optind];
 439     if (argv0) {
 440         argv[optind] = argv0;
 441     }
 442
 443     if (!trace_init_backends()) {
 444         exit(1);
 445     }
 446     trace_init_file();
 447
 448     /* Zero out regs */
 449     memset(regs, 0, sizeof(struct target_pt_regs));
 450
 451     /* Zero bsd params */
 452     memset(&bprm, 0, sizeof(bprm));
 453
 454     /* Zero out image_info */
 455     memset(info, 0, sizeof(struct image_info));
 456
 457     /* Scan interp_prefix dir for replacement files. */
 458     init_paths(interp_prefix);
 459
 460     if (cpu_model == NULL) {
 461         cpu_model = TARGET_DEFAULT_CPU_MODEL;
 462     }
 463
 464     cpu_type = parse_cpu_option(cpu_model);
 465
 466     /* init tcg before creating CPUs and to get qemu_host_page_size */
 467     {
 468         AccelClass *ac = ACCEL_GET_CLASS(current_accel());
 469
 470         accel_init_interfaces(ac);
 471         ac->init_machine(NULL);
 472     }
 473     cpu = cpu_create(cpu_type);
 474     env = cpu->env_ptr;
 475     cpu_reset(cpu);
 476     thread_cpu = cpu;
 477
 478     if (getenv("QEMU_STRACE")) {
 479         do_strace = 1;
 480     }
 481
 482     target_environ = envlist_to_environ(envlist, NULL);
 483     envlist_free(envlist);
 484
 485     if (reserved_va) {
 486             mmap_next_start = reserved_va;
 487     }
 488
 489     {
 490         Error *err = NULL;
 491         if (seed_optarg != NULL) {
 492             qemu_guest_random_seed_main(seed_optarg, &err);
 493         } else {
 494             qcrypto_init(&err);
 495         }
 496         if (err) {
 497             error_reportf_err(err, "cannot initialize crypto: ");
 498             exit(1);
 499         }
 500     }
 501
 502     /*
 503      * Now that page sizes are configured we can do
 504      * proper page alignment for guest_base.
 505      */
 506     guest_base = HOST_PAGE_ALIGN(guest_base);
 507
 508     if (loader_exec(filename, argv + optind, target_environ, regs, info,
 509                     &bprm) != 0) {
 510         printf("Error loading %s\n", filename);
 511         _exit(1);
 512     }
 513
 514     for (wrk = target_environ; *wrk; wrk++) {
 515         g_free(*wrk);
 516     }
 517
 518     g_free(target_environ);
 519
 520     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
 521         qemu_log("guest_base  %p\n", (void *)guest_base);
 522         log_page_dump("binary load");
 523
 524         qemu_log("start_brk   0x" TARGET_ABI_FMT_lx "\n", info->start_brk);
 525         qemu_log("end_code    0x" TARGET_ABI_FMT_lx "\n", info->end_code);
 526         qemu_log("start_code  0x" TARGET_ABI_FMT_lx "\n",
 527                  info->start_code);
 528         qemu_log("start_data  0x" TARGET_ABI_FMT_lx "\n",
 529                  info->start_data);
 530         qemu_log("end_data    0x" TARGET_ABI_FMT_lx "\n", info->end_data);
 531         qemu_log("start_stack 0x" TARGET_ABI_FMT_lx "\n",
 532                  info->start_stack);
 533         qemu_log("brk         0x" TARGET_ABI_FMT_lx "\n", info->brk);
 534         qemu_log("entry       0x" TARGET_ABI_FMT_lx "\n", info->entry);
 535     }
 536
 537     /* build Task State */
 538     ts = g_new0(TaskState, 1);
 539     init_task_state(ts);
 540     ts->info = info;
 541     ts->bprm = &bprm;
 542     cpu->opaque = ts;
 543
 544     target_set_brk(info->brk);
 545     syscall_init();
 546     signal_init();
 547
 548     /*
 549      * Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
 550      * generating the prologue until now so that the prologue can take
 551      * the real value of GUEST_BASE into account.
 552      */
 553     tcg_prologue_init(tcg_ctx);
 554
 555     target_cpu_init(env, regs);
 556
 557     if (gdbstub) {
 558         gdbserver_start(gdbstub);
 559         gdb_handlesig(cpu, 0);
 560     }
 561     cpu_loop(env);
 562     /* never exits */
 563     return 0;
 564 }