linux-user/main.c

   1 /*
   2  *  qemu main
   3  *
   4  *  Copyright (c) 2003 Fabrice Bellard
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20 #include <stdlib.h>
  21 #include <stdio.h>
  22 #include <stdarg.h>
  23 #include <string.h>
  24 #include <errno.h>
  25 #include <unistd.h>
  26
  27 #include "qemu.h"
  28
  29 #include "cpu-i386.h"
  30
  31 #define DEBUG_LOGFILE "/tmp/qemu.log"
  32
  33 FILE *logfile = NULL;
  34 int loglevel;
  35 static const char *interp_prefix = CONFIG_QEMU_PREFIX;
  36
  37 #ifdef __i386__
  38 /* Force usage of an ELF interpreter even if it is an ELF shared
  39    object ! */
  40 const char interp[] __attribute__((section(".interp"))) = "/lib/ld-linux.so.2";
  41 #endif
  42
  43 /* for recent libc, we add these dummies symbol which are not declared
  44    when generating a linked object (bug in ld ?) */
  45 #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 3)
  46 long __init_array_start[0];
  47 long __init_array_end[0];
  48 long __fini_array_start[0];
  49 long __fini_array_end[0];
  50 #endif
  51
  52 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
  53    we allocate a bigger stack. Need a better solution, for example
  54    by remapping the process stack directly at the right place */
  55 unsigned long x86_stack_size = 512 * 1024;
  56
  57 void gemu_log(const char *fmt, ...)
  58 {
  59     va_list ap;
  60
  61     va_start(ap, fmt);
  62     vfprintf(stderr, fmt, ap);
  63     va_end(ap);
  64 }
  65
  66 #ifdef TARGET_I386
  67 /***********************************************************/
  68 /* CPUX86 core interface */
  69
  70 void cpu_x86_outb(CPUX86State *env, int addr, int val)
  71 {
  72     fprintf(stderr, "outb: port=0x%04x, data=%02x\n", addr, val);
  73 }
  74
  75 void cpu_x86_outw(CPUX86State *env, int addr, int val)
  76 {
  77     fprintf(stderr, "outw: port=0x%04x, data=%04x\n", addr, val);
  78 }
  79
  80 void cpu_x86_outl(CPUX86State *env, int addr, int val)
  81 {
  82     fprintf(stderr, "outl: port=0x%04x, data=%08x\n", addr, val);
  83 }
  84
  85 int cpu_x86_inb(CPUX86State *env, int addr)
  86 {
  87     fprintf(stderr, "inb: port=0x%04x\n", addr);
  88     return 0;
  89 }
  90
  91 int cpu_x86_inw(CPUX86State *env, int addr)
  92 {
  93     fprintf(stderr, "inw: port=0x%04x\n", addr);
  94     return 0;
  95 }
  96
  97 int cpu_x86_inl(CPUX86State *env, int addr)
  98 {
  99     fprintf(stderr, "inl: port=0x%04x\n", addr);
 100     return 0;
 101 }
 102
 103 static void write_dt(void *ptr, unsigned long addr, unsigned long limit,
 104                      int flags)
 105 {
 106     unsigned int e1, e2;
 107     e1 = (addr << 16) | (limit & 0xffff);
 108     e2 = ((addr >> 16) & 0xff) | (addr & 0xff000000) | (limit & 0x000f0000);
 109     e2 |= flags;
 110     stl((uint8_t *)ptr, e1);
 111     stl((uint8_t *)ptr + 4, e2);
 112 }
 113
 114 static void set_gate(void *ptr, unsigned int type, unsigned int dpl,
 115                      unsigned long addr, unsigned int sel)
 116 {
 117     unsigned int e1, e2;
 118     e1 = (addr & 0xffff) | (sel << 16);
 119     e2 = (addr & 0xffff0000) | 0x8000 | (dpl << 13) | (type << 8);
 120     stl((uint8_t *)ptr, e1);
 121     stl((uint8_t *)ptr + 4, e2);
 122 }
 123
 124 uint64_t gdt_table[6];
 125 uint64_t idt_table[256];
 126
 127 /* only dpl matters as we do only user space emulation */
 128 static void set_idt(int n, unsigned int dpl)
 129 {
 130     set_gate(idt_table + n, 0, dpl, 0, 0);
 131 }
 132
 133 void cpu_loop(CPUX86State *env)
 134 {
 135     int trapnr;
 136     uint8_t *pc;
 137     target_siginfo_t info;
 138
 139     for(;;) {
 140         trapnr = cpu_x86_exec(env);
 141         switch(trapnr) {
 142         case 0x80:
 143             /* linux syscall */
 144             env->regs[R_EAX] = do_syscall(env,
 145                                           env->regs[R_EAX],
 146                                           env->regs[R_EBX],
 147                                           env->regs[R_ECX],
 148                                           env->regs[R_EDX],
 149                                           env->regs[R_ESI],
 150                                           env->regs[R_EDI],
 151                                           env->regs[R_EBP]);
 152             break;
 153         case EXCP0B_NOSEG:
 154         case EXCP0C_STACK:
 155             info.si_signo = SIGBUS;
 156             info.si_errno = 0;
 157             info.si_code = TARGET_SI_KERNEL;
 158             info._sifields._sigfault._addr = 0;
 159             queue_signal(info.si_signo, &info);
 160             break;
 161         case EXCP0D_GPF:
 162             if (env->eflags & VM_MASK) {
 163                 handle_vm86_fault(env);
 164             } else {
 165                 info.si_signo = SIGSEGV;
 166                 info.si_errno = 0;
 167                 info.si_code = TARGET_SI_KERNEL;
 168                 info._sifields._sigfault._addr = 0;
 169                 queue_signal(info.si_signo, &info);
 170             }
 171             break;
 172         case EXCP0E_PAGE:
 173             info.si_signo = SIGSEGV;
 174             info.si_errno = 0;
 175             if (!(env->error_code & 1))
 176                 info.si_code = TARGET_SEGV_MAPERR;
 177             else
 178                 info.si_code = TARGET_SEGV_ACCERR;
 179             info._sifields._sigfault._addr = env->cr2;
 180             queue_signal(info.si_signo, &info);
 181             break;
 182         case EXCP00_DIVZ:
 183             if (env->eflags & VM_MASK) {
 184                 handle_vm86_trap(env, trapnr);
 185             } else {
 186                 /* division by zero */
 187                 info.si_signo = SIGFPE;
 188                 info.si_errno = 0;
 189                 info.si_code = TARGET_FPE_INTDIV;
 190                 info._sifields._sigfault._addr = env->eip;
 191                 queue_signal(info.si_signo, &info);
 192             }
 193             break;
 194         case EXCP01_SSTP:
 195         case EXCP03_INT3:
 196             if (env->eflags & VM_MASK) {
 197                 handle_vm86_trap(env, trapnr);
 198             } else {
 199                 info.si_signo = SIGTRAP;
 200                 info.si_errno = 0;
 201                 if (trapnr == EXCP01_SSTP) {
 202                     info.si_code = TARGET_TRAP_BRKPT;
 203                     info._sifields._sigfault._addr = env->eip;
 204                 } else {
 205                     info.si_code = TARGET_SI_KERNEL;
 206                     info._sifields._sigfault._addr = 0;
 207                 }
 208                 queue_signal(info.si_signo, &info);
 209             }
 210             break;
 211         case EXCP04_INTO:
 212         case EXCP05_BOUND:
 213             if (env->eflags & VM_MASK) {
 214                 handle_vm86_trap(env, trapnr);
 215             } else {
 216                 info.si_signo = SIGSEGV;
 217                 info.si_errno = 0;
 218                 info.si_code = TARGET_SI_KERNEL;
 219                 info._sifields._sigfault._addr = 0;
 220                 queue_signal(info.si_signo, &info);
 221             }
 222             break;
 223         case EXCP06_ILLOP:
 224             info.si_signo = SIGILL;
 225             info.si_errno = 0;
 226             info.si_code = TARGET_ILL_ILLOPN;
 227             info._sifields._sigfault._addr = env->eip;
 228             queue_signal(info.si_signo, &info);
 229             break;
 230         case EXCP_INTERRUPT:
 231             /* just indicate that signals should be handled asap */
 232             break;
 233         default:
 234             pc = env->seg_cache[R_CS].base + env->eip;
 235             fprintf(stderr, "qemu: 0x%08lx: unhandled CPU exception 0x%x - aborting\n",
 236                     (long)pc, trapnr);
 237             abort();
 238         }
 239         process_pending_signals(env);
 240     }
 241 }
 242 #endif
 243
 244 #ifdef TARGET_ARM
 245
 246 #define ARM_SYSCALL_BASE        0x900000
 247
 248 void cpu_loop(CPUARMState *env)
 249 {
 250     int trapnr;
 251     unsigned int n, insn;
 252     target_siginfo_t info;
 253
 254     for(;;) {
 255         trapnr = cpu_arm_exec(env);
 256         switch(trapnr) {
 257         case EXCP_UDEF:
 258             info.si_signo = SIGILL;
 259             info.si_errno = 0;
 260             info.si_code = TARGET_ILL_ILLOPN;
 261             info._sifields._sigfault._addr = env->regs[15];
 262             queue_signal(info.si_signo, &info);
 263             break;
 264         case EXCP_SWI:
 265             {
 266                 /* system call */
 267                 insn = ldl((void *)(env->regs[15] - 4));
 268                 n = insn & 0xffffff;
 269                 if (n >= ARM_SYSCALL_BASE) {
 270                     /* linux syscall */
 271                     n -= ARM_SYSCALL_BASE;
 272                     env->regs[0] = do_syscall(env,
 273                                               n,
 274                                               env->regs[0],
 275                                               env->regs[1],
 276                                               env->regs[2],
 277                                               env->regs[3],
 278                                               env->regs[4],
 279                                               0);
 280                 } else {
 281                     goto error;
 282                 }
 283             }
 284             break;
 285         default:
 286         error:
 287             fprintf(stderr, "qemu: unhandled CPU exception 0x%x - aborting\n",
 288                     trapnr);
 289             cpu_arm_dump_state(env, stderr, 0);
 290             abort();
 291         }
 292         process_pending_signals(env);
 293     }
 294 }
 295
 296 #endif
 297
 298 void usage(void)
 299 {
 300     printf("qemu version " QEMU_VERSION ", Copyright (c) 2003 Fabrice Bellard\n"
 301            "usage: qemu [-h] [-d] [-L path] [-s size] program [arguments...]\n"
 302            "Linux CPU emulator (compiled for %s emulation)\n"
 303            "\n"
 304            "-h           print this help\n"
 305            "-L path      set the elf interpreter prefix (default=%s)\n"
 306            "-s size      set the stack size in bytes (default=%ld)\n"
 307            "\n"
 308            "debug options:\n"
 309            "-d           activate log (logfile=%s)\n"
 310            "-p pagesize  set the host page size to 'pagesize'\n",
 311            TARGET_ARCH,
 312            interp_prefix,
 313            x86_stack_size,
 314            DEBUG_LOGFILE);
 315     _exit(1);
 316 }
 317
 318 /* XXX: currently only used for async signals (see signal.c) */
 319 CPUState *global_env;
 320 /* used to free thread contexts */
 321 TaskState *first_task_state;
 322
 323 int main(int argc, char **argv)
 324 {
 325     const char *filename;
 326     struct target_pt_regs regs1, *regs = &regs1;
 327     struct image_info info1, *info = &info1;
 328     TaskState ts1, *ts = &ts1;
 329     CPUState *env;
 330     int optind;
 331     const char *r;
 332
 333     if (argc <= 1)
 334         usage();
 335
 336     loglevel = 0;
 337     optind = 1;
 338     for(;;) {
 339         if (optind >= argc)
 340             break;
 341         r = argv[optind];
 342         if (r[0] != '-')
 343             break;
 344         optind++;
 345         r++;
 346         if (!strcmp(r, "-")) {
 347             break;
 348         } else if (!strcmp(r, "d")) {
 349             loglevel = 1;
 350         } else if (!strcmp(r, "s")) {
 351             r = argv[optind++];
 352             x86_stack_size = strtol(r, (char **)&r, 0);
 353             if (x86_stack_size <= 0)
 354                 usage();
 355             if (*r == 'M')
 356                 x86_stack_size *= 1024 * 1024;
 357             else if (*r == 'k' || *r == 'K')
 358                 x86_stack_size *= 1024;
 359         } else if (!strcmp(r, "L")) {
 360             interp_prefix = argv[optind++];
 361         } else if (!strcmp(r, "p")) {
 362             host_page_size = atoi(argv[optind++]);
 363             if (host_page_size == 0 ||
 364                 (host_page_size & (host_page_size - 1)) != 0) {
 365                 fprintf(stderr, "page size must be a power of two\n");
 366                 exit(1);
 367             }
 368         } else {
 369             usage();
 370         }
 371     }
 372     if (optind >= argc)
 373         usage();
 374     filename = argv[optind];
 375
 376     /* init debug */
 377     if (loglevel) {
 378         logfile = fopen(DEBUG_LOGFILE, "w");
 379         if (!logfile) {
 380             perror(DEBUG_LOGFILE);
 381             _exit(1);
 382         }
 383         setvbuf(logfile, NULL, _IOLBF, 0);
 384     }
 385
 386     /* Zero out regs */
 387     memset(regs, 0, sizeof(struct target_pt_regs));
 388
 389     /* Zero out image_info */
 390     memset(info, 0, sizeof(struct image_info));
 391
 392     /* Scan interp_prefix dir for replacement files. */
 393     init_paths(interp_prefix);
 394
 395     /* NOTE: we need to init the CPU at this stage to get the
 396        host_page_size */
 397     env = cpu_init();
 398
 399     if (elf_exec(filename, argv+optind, environ, regs, info) != 0) {
 400         printf("Error loading %s\n", filename);
 401         _exit(1);
 402     }
 403
 404     if (loglevel) {
 405         page_dump(logfile);
 406
 407         fprintf(logfile, "start_brk   0x%08lx\n" , info->start_brk);
 408         fprintf(logfile, "end_code    0x%08lx\n" , info->end_code);
 409         fprintf(logfile, "start_code  0x%08lx\n" , info->start_code);
 410         fprintf(logfile, "end_data    0x%08lx\n" , info->end_data);
 411         fprintf(logfile, "start_stack 0x%08lx\n" , info->start_stack);
 412         fprintf(logfile, "brk         0x%08lx\n" , info->brk);
 413         fprintf(logfile, "entry       0x%08lx\n" , info->entry);
 414     }
 415
 416     target_set_brk((char *)info->brk);
 417     syscall_init();
 418     signal_init();
 419
 420     global_env = env;
 421
 422     /* build Task State */
 423     memset(ts, 0, sizeof(TaskState));
 424     env->opaque = ts;
 425     ts->used = 1;
 426
 427 #if defined(TARGET_I386)
 428     /* linux register setup */
 429     env->regs[R_EAX] = regs->eax;
 430     env->regs[R_EBX] = regs->ebx;
 431     env->regs[R_ECX] = regs->ecx;
 432     env->regs[R_EDX] = regs->edx;
 433     env->regs[R_ESI] = regs->esi;
 434     env->regs[R_EDI] = regs->edi;
 435     env->regs[R_EBP] = regs->ebp;
 436     env->regs[R_ESP] = regs->esp;
 437     env->eip = regs->eip;
 438
 439     /* linux interrupt setup */
 440     env->idt.base = (void *)idt_table;
 441     env->idt.limit = sizeof(idt_table) - 1;
 442     set_idt(0, 0);
 443     set_idt(1, 0);
 444     set_idt(2, 0);
 445     set_idt(3, 3);
 446     set_idt(4, 3);
 447     set_idt(5, 3);
 448     set_idt(6, 0);
 449     set_idt(7, 0);
 450     set_idt(8, 0);
 451     set_idt(9, 0);
 452     set_idt(10, 0);
 453     set_idt(11, 0);
 454     set_idt(12, 0);
 455     set_idt(13, 0);
 456     set_idt(14, 0);
 457     set_idt(15, 0);
 458     set_idt(16, 0);
 459     set_idt(17, 0);
 460     set_idt(18, 0);
 461     set_idt(19, 0);
 462     set_idt(0x80, 3);
 463
 464     /* linux segment setup */
 465     env->gdt.base = (void *)gdt_table;
 466     env->gdt.limit = sizeof(gdt_table) - 1;
 467     write_dt(&gdt_table[__USER_CS >> 3], 0, 0xfffff,
 468              DESC_G_MASK | DESC_B_MASK | DESC_P_MASK | DESC_S_MASK |
 469              (3 << DESC_DPL_SHIFT) | (0xa << DESC_TYPE_SHIFT));
 470     write_dt(&gdt_table[__USER_DS >> 3], 0, 0xfffff,
 471              DESC_G_MASK | DESC_B_MASK | DESC_P_MASK | DESC_S_MASK |
 472              (3 << DESC_DPL_SHIFT) | (0x2 << DESC_TYPE_SHIFT));
 473     cpu_x86_load_seg(env, R_CS, __USER_CS);
 474     cpu_x86_load_seg(env, R_DS, __USER_DS);
 475     cpu_x86_load_seg(env, R_ES, __USER_DS);
 476     cpu_x86_load_seg(env, R_SS, __USER_DS);
 477     cpu_x86_load_seg(env, R_FS, __USER_DS);
 478     cpu_x86_load_seg(env, R_GS, __USER_DS);
 479 #elif defined(TARGET_ARM)
 480     {
 481         int i;
 482         for(i = 0; i < 16; i++) {
 483             env->regs[i] = regs->uregs[i];
 484         }
 485         env->cpsr = regs->uregs[16];
 486     }
 487 #else
 488 #error unsupported target CPU
 489 #endif
 490
 491     cpu_loop(env);
 492     /* never exits */
 493     return 0;
 494 }