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