qemu

main.c (16234B)

---

 /*
  *  qemu bsd user main
  *
  *  Copyright (c) 2003-2008 Fabrice Bellard
  *  Copyright (c) 2013-14 Stacey Son
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <sys/types.h>
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <sys/sysctl.h>
 
 #include "qemu/osdep.h"
 #include "qemu/help-texts.h"
 #include "qemu/units.h"
 #include "qemu/accel.h"
 #include "qemu-version.h"
 #include <machine/trap.h>
 
 #include "qapi/error.h"
 #include "qemu.h"
 #include "qemu/config-file.h"
 #include "qemu/error-report.h"
 #include "qemu/path.h"
 #include "qemu/help_option.h"
 #include "qemu/module.h"
 #include "exec/exec-all.h"
 #include "tcg/tcg.h"
 #include "qemu/timer.h"
 #include "qemu/envlist.h"
 #include "qemu/cutils.h"
 #include "exec/log.h"
 #include "trace/control.h"
 #include "crypto/init.h"
 #include "qemu/guest-random.h"
 
 #include "host-os.h"
 #include "target_arch_cpu.h"
 
 int singlestep;
 uintptr_t guest_base;
 bool have_guest_base;
 /*
  * When running 32-on-64 we should make sure we can fit all of the possible
  * guest address space into a contiguous chunk of virtual host memory.
  *
  * This way we will never overlap with our own libraries or binaries or stack
  * or anything else that QEMU maps.
  *
  * Many cpus reserve the high bit (or more than one for some 64-bit cpus)
  * of the address for the kernel.  Some cpus rely on this and user space
  * uses the high bit(s) for pointer tagging and the like.  For them, we
  * must preserve the expected address space.
  */
 #ifndef MAX_RESERVED_VA
 # if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
 #  if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
       (TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
 /*
  * There are a number of places where we assign reserved_va to a variable
  * of type abi_ulong and expect it to fit.  Avoid the last page.
  */
 #   define MAX_RESERVED_VA  (0xfffffffful & TARGET_PAGE_MASK)
 #  else
 #   define MAX_RESERVED_VA  (1ul << TARGET_VIRT_ADDR_SPACE_BITS)
 #  endif
 # else
 #  define MAX_RESERVED_VA  0
 # endif
 #endif
 
 /*
  * That said, reserving *too* much vm space via mmap can run into problems
  * with rlimits, oom due to page table creation, etc.  We will still try it,
  * if directed by the command-line option, but not by default.
  */
 #if HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32
 unsigned long reserved_va = MAX_RESERVED_VA;
 #else
 unsigned long reserved_va;
 #endif
 
 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
 const char *qemu_uname_release;
 char qemu_proc_pathname[PATH_MAX];  /* full path to exeutable */
 
 unsigned long target_maxtsiz = TARGET_MAXTSIZ;   /* max text size */
 unsigned long target_dfldsiz = TARGET_DFLDSIZ;   /* initial data size limit */
 unsigned long target_maxdsiz = TARGET_MAXDSIZ;   /* max data size */
 unsigned long target_dflssiz = TARGET_DFLSSIZ;   /* initial data size limit */
 unsigned long target_maxssiz = TARGET_MAXSSIZ;   /* max stack size */
 unsigned long target_sgrowsiz = TARGET_SGROWSIZ; /* amount to grow stack */
 
 /* Helper routines for implementing atomic operations. */
 
 void fork_start(void)
 {
     start_exclusive();
     cpu_list_lock();
     mmap_fork_start();
 }
 
 void fork_end(int child)
 {
     if (child) {
         CPUState *cpu, *next_cpu;
         /*
          * Child processes created by fork() only have a single thread.  Discard
          * information about the parent threads.
          */
         CPU_FOREACH_SAFE(cpu, next_cpu) {
             if (cpu != thread_cpu) {
                 QTAILQ_REMOVE_RCU(&cpus, cpu, node);
             }
         }
         mmap_fork_end(child);
         /*
          * qemu_init_cpu_list() takes care of reinitializing the exclusive
          * state, so we don't need to end_exclusive() here.
          */
         qemu_init_cpu_list();
         gdbserver_fork(thread_cpu);
     } else {
         mmap_fork_end(child);
         cpu_list_unlock();
         end_exclusive();
     }
 }
 
 void cpu_loop(CPUArchState *env)
 {
     target_cpu_loop(env);
 }
 
 static void usage(void)
 {
     printf("qemu-" TARGET_NAME " version " QEMU_FULL_VERSION
            "\n" QEMU_COPYRIGHT "\n"
            "usage: qemu-" TARGET_NAME " [options] program [arguments...]\n"
            "BSD CPU emulator (compiled for %s emulation)\n"
            "\n"
            "Standard options:\n"
            "-h                print this help\n"
            "-g port           wait gdb connection to port\n"
            "-L path           set the elf interpreter prefix (default=%s)\n"
            "-s size           set the stack size in bytes (default=%ld)\n"
            "-cpu model        select CPU (-cpu help for list)\n"
            "-drop-ld-preload  drop LD_PRELOAD for target process\n"
            "-E var=value      sets/modifies targets environment variable(s)\n"
            "-U var            unsets targets environment variable(s)\n"
            "-B address        set guest_base address to address\n"
            "\n"
            "Debug options:\n"
            "-d item1[,...]    enable logging of specified items\n"
            "                  (use '-d help' for a list of log items)\n"
            "-D logfile        write logs to 'logfile' (default stderr)\n"
            "-singlestep       always run in singlestep mode\n"
            "-strace           log system calls\n"
            "-trace            [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
            "                  specify tracing options\n"
            "\n"
            "Environment variables:\n"
            "QEMU_STRACE       Print system calls and arguments similar to the\n"
            "                  'strace' program.  Enable by setting to any value.\n"
            "You can use -E and -U options to set/unset environment variables\n"
            "for target process.  It is possible to provide several variables\n"
            "by repeating the option.  For example:\n"
            "    -E var1=val2 -E var2=val2 -U LD_PRELOAD -U LD_DEBUG\n"
            "Note that if you provide several changes to single variable\n"
            "last change will stay in effect.\n"
            "\n"
            QEMU_HELP_BOTTOM "\n"
            ,
            TARGET_NAME,
            interp_prefix,
            target_dflssiz);
     exit(1);
 }
 
 __thread CPUState *thread_cpu;
 
 void stop_all_tasks(void)
 {
     /*
      * We trust when using NPTL (pthreads) start_exclusive() handles thread
      * stopping correctly.
      */
     start_exclusive();
 }
 
 bool qemu_cpu_is_self(CPUState *cpu)
 {
     return thread_cpu == cpu;
 }
 
 void qemu_cpu_kick(CPUState *cpu)
 {
     cpu_exit(cpu);
 }
 
 /* Assumes contents are already zeroed.  */
 static void init_task_state(TaskState *ts)
 {
     ts->sigaltstack_used = (struct target_sigaltstack) {
         .ss_sp = 0,
         .ss_size = 0,
         .ss_flags = TARGET_SS_DISABLE,
     };
 }
 
 void gemu_log(const char *fmt, ...)
 {
     va_list ap;
 
     va_start(ap, fmt);
     vfprintf(stderr, fmt, ap);
     va_end(ap);
 }
 
 static void
 adjust_ssize(void)
 {
     struct rlimit rl;
 
     if (getrlimit(RLIMIT_STACK, &rl) != 0) {
         return;
     }
 
     target_maxssiz = MIN(target_maxssiz, rl.rlim_max);
     target_dflssiz = MIN(MAX(target_dflssiz, rl.rlim_cur), target_maxssiz);
 
     rl.rlim_max = target_maxssiz;
     rl.rlim_cur = target_dflssiz;
     setrlimit(RLIMIT_STACK, &rl);
 }
 
 static void save_proc_pathname(char *argv0)
 {
     int mib[4];
     size_t len;
 
     mib[0] = CTL_KERN;
     mib[1] = KERN_PROC;
     mib[2] = KERN_PROC_PATHNAME;
     mib[3] = -1;
 
     len = sizeof(qemu_proc_pathname);
     if (sysctl(mib, 4, qemu_proc_pathname, &len, NULL, 0)) {
         perror("sysctl");
     }
 }
 
 int main(int argc, char **argv)
 {
     const char *filename;
     const char *cpu_model;
     const char *cpu_type;
     const char *log_file = NULL;
     const char *log_mask = NULL;
     const char *seed_optarg = NULL;
     struct target_pt_regs regs1, *regs = &regs1;
     struct image_info info1, *info = &info1;
     struct bsd_binprm bprm;
     TaskState *ts;
     CPUArchState *env;
     CPUState *cpu;
     int optind, rv;
     const char *r;
     const char *gdbstub = NULL;
     char **target_environ, **wrk;
     envlist_t *envlist = NULL;
     char *argv0 = NULL;
 
     adjust_ssize();
 
     if (argc <= 1) {
         usage();
     }
 
     save_proc_pathname(argv[0]);
 
     error_init(argv[0]);
     module_call_init(MODULE_INIT_TRACE);
     qemu_init_cpu_list();
     module_call_init(MODULE_INIT_QOM);
 
     envlist = envlist_create();
 
     /* add current environment into the list */
     for (wrk = environ; *wrk != NULL; wrk++) {
         (void) envlist_setenv(envlist, *wrk);
     }
 
     cpu_model = NULL;
 
     qemu_add_opts(&qemu_trace_opts);
 
     optind = 1;
     for (;;) {
         if (optind >= argc) {
             break;
         }
         r = argv[optind];
         if (r[0] != '-') {
             break;
         }
         optind++;
         r++;
         if (!strcmp(r, "-")) {
             break;
         } else if (!strcmp(r, "d")) {
             if (optind >= argc) {
                 break;
             }
             log_mask = argv[optind++];
         } else if (!strcmp(r, "D")) {
             if (optind >= argc) {
                 break;
             }
             log_file = argv[optind++];
         } else if (!strcmp(r, "E")) {
             r = argv[optind++];
             if (envlist_setenv(envlist, r) != 0) {
                 usage();
             }
         } else if (!strcmp(r, "ignore-environment")) {
             envlist_free(envlist);
             envlist = envlist_create();
         } else if (!strcmp(r, "U")) {
             r = argv[optind++];
             if (envlist_unsetenv(envlist, r) != 0) {
                 usage();
             }
         } else if (!strcmp(r, "s")) {
             r = argv[optind++];
             rv = qemu_strtoul(r, &r, 0, &target_dflssiz);
             if (rv < 0 || target_dflssiz <= 0) {
                 usage();
             }
             if (*r == 'M') {
                 target_dflssiz *= 1024 * 1024;
             } else if (*r == 'k' || *r == 'K') {
                 target_dflssiz *= 1024;
             }
             if (target_dflssiz > target_maxssiz) {
                 usage();
             }
         } else if (!strcmp(r, "L")) {
             interp_prefix = argv[optind++];
         } else if (!strcmp(r, "p")) {
             qemu_host_page_size = atoi(argv[optind++]);
             if (qemu_host_page_size == 0 ||
                 (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
                 fprintf(stderr, "page size must be a power of two\n");
                 exit(1);
             }
         } else if (!strcmp(r, "g")) {
             gdbstub = g_strdup(argv[optind++]);
         } else if (!strcmp(r, "r")) {
             qemu_uname_release = argv[optind++];
         } else if (!strcmp(r, "cpu")) {
             cpu_model = argv[optind++];
             if (is_help_option(cpu_model)) {
                 /* XXX: implement xxx_cpu_list for targets that still miss it */
 #if defined(cpu_list)
                 cpu_list();
 #endif
                 exit(1);
             }
         } else if (!strcmp(r, "B")) {
             rv = qemu_strtoul(argv[optind++], NULL, 0, &guest_base);
             if (rv < 0) {
                 usage();
             }
             have_guest_base = true;
         } else if (!strcmp(r, "drop-ld-preload")) {
             (void) envlist_unsetenv(envlist, "LD_PRELOAD");
         } else if (!strcmp(r, "seed")) {
             seed_optarg = optarg;
         } else if (!strcmp(r, "singlestep")) {
             singlestep = 1;
         } else if (!strcmp(r, "strace")) {
             do_strace = 1;
         } else if (!strcmp(r, "trace")) {
             trace_opt_parse(optarg);
         } else if (!strcmp(r, "0")) {
             argv0 = argv[optind++];
         } else {
             usage();
         }
     }
 
     /* init debug */
     {
         int mask = 0;
         if (log_mask) {
             mask = qemu_str_to_log_mask(log_mask);
             if (!mask) {
                 qemu_print_log_usage(stdout);
                 exit(1);
             }
         }
         qemu_set_log_filename_flags(log_file, mask, &error_fatal);
     }
 
     if (optind >= argc) {
         usage();
     }
     filename = argv[optind];
     if (argv0) {
         argv[optind] = argv0;
     }
 
     if (!trace_init_backends()) {
         exit(1);
     }
     trace_init_file();
 
     /* Zero out regs */
     memset(regs, 0, sizeof(struct target_pt_regs));
 
     /* Zero bsd params */
     memset(&bprm, 0, sizeof(bprm));
 
     /* Zero out image_info */
     memset(info, 0, sizeof(struct image_info));
 
     /* Scan interp_prefix dir for replacement files. */
     init_paths(interp_prefix);
 
     if (cpu_model == NULL) {
         cpu_model = TARGET_DEFAULT_CPU_MODEL;
     }
 
     cpu_type = parse_cpu_option(cpu_model);
 
     /* init tcg before creating CPUs and to get qemu_host_page_size */
     {
         AccelClass *ac = ACCEL_GET_CLASS(current_accel());
 
         accel_init_interfaces(ac);
         ac->init_machine(NULL);
     }
     cpu = cpu_create(cpu_type);
     env = cpu->env_ptr;
     cpu_reset(cpu);
     thread_cpu = cpu;
 
     if (getenv("QEMU_STRACE")) {
         do_strace = 1;
     }
 
     target_environ = envlist_to_environ(envlist, NULL);
     envlist_free(envlist);
 
     if (reserved_va) {
             mmap_next_start = reserved_va;
     }
 
     {
         Error *err = NULL;
         if (seed_optarg != NULL) {
             qemu_guest_random_seed_main(seed_optarg, &err);
         } else {
             qcrypto_init(&err);
         }
         if (err) {
             error_reportf_err(err, "cannot initialize crypto: ");
             exit(1);
         }
     }
 
     /*
      * Now that page sizes are configured we can do
      * proper page alignment for guest_base.
      */
     guest_base = HOST_PAGE_ALIGN(guest_base);
 
     if (loader_exec(filename, argv + optind, target_environ, regs, info,
                     &bprm) != 0) {
         printf("Error loading %s\n", filename);
         _exit(1);
     }
 
     for (wrk = target_environ; *wrk; wrk++) {
         g_free(*wrk);
     }
 
     g_free(target_environ);
 
     if (qemu_loglevel_mask(CPU_LOG_PAGE)) {
         FILE *f = qemu_log_trylock();
         if (f) {
             fprintf(f, "guest_base  %p\n", (void *)guest_base);
             fprintf(f, "page layout changed following binary load\n");
             page_dump(f);
 
             fprintf(f, "start_brk   0x" TARGET_ABI_FMT_lx "\n",
                     info->start_brk);
             fprintf(f, "end_code    0x" TARGET_ABI_FMT_lx "\n",
                     info->end_code);
             fprintf(f, "start_code  0x" TARGET_ABI_FMT_lx "\n",
                     info->start_code);
             fprintf(f, "start_data  0x" TARGET_ABI_FMT_lx "\n",
                     info->start_data);
             fprintf(f, "end_data    0x" TARGET_ABI_FMT_lx "\n",
                     info->end_data);
             fprintf(f, "start_stack 0x" TARGET_ABI_FMT_lx "\n",
                     info->start_stack);
             fprintf(f, "brk         0x" TARGET_ABI_FMT_lx "\n", info->brk);
             fprintf(f, "entry       0x" TARGET_ABI_FMT_lx "\n", info->entry);
 
             qemu_log_unlock(f);
         }
     }
 
     /* build Task State */
     ts = g_new0(TaskState, 1);
     init_task_state(ts);
     ts->info = info;
     ts->bprm = &bprm;
     cpu->opaque = ts;
 
     target_set_brk(info->brk);
     syscall_init();
     signal_init();
 
     /*
      * Now that we've loaded the binary, GUEST_BASE is fixed.  Delay
      * generating the prologue until now so that the prologue can take
      * the real value of GUEST_BASE into account.
      */
     tcg_prologue_init(tcg_ctx);
 
     target_cpu_init(env, regs);
 
     if (gdbstub) {
         gdbserver_start(gdbstub);
         gdb_handlesig(cpu, 0);
     }
     cpu_loop(env);
     /* never exits */
     return 0;
 }