[mirror_qemu.git] / linux-user / main.c

/*
 *  qemu main
 * 
 *  Copyright (c) 2003 Fabrice Bellard
 *
 *  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, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>

#include "qemu.h"

#include "cpu-i386.h"

#define DEBUG_LOGFILE "/tmp/qemu.log"

FILE *logfile = NULL;
int loglevel;
static const char *interp_prefix = CONFIG_QEMU_PREFIX;

#ifdef __i386__
/* Force usage of an ELF interpreter even if it is an ELF shared
   object ! */
const char interp[] __attribute__((section(".interp"))) = "/lib/ld-linux.so.2";

/* for recent libc, we add these dummies symbol which are not declared
   when generating a linked object (bug in ld ?) */
#if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 3)
long __init_array_start[0];
long __init_array_end[0];
long __fini_array_start[0];
long __fini_array_end[0];
#endif

#endif

/* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
   we allocate a bigger stack. Need a better solution, for example
   by remapping the process stack directly at the right place */
unsigned long x86_stack_size = 512 * 1024;

void gemu_log(const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
}

/***********************************************************/
/* CPUX86 core interface */

void cpu_x86_outb(CPUX86State *env, int addr, int val)
{
    fprintf(stderr, "outb: port=0x%04x, data=%02x\n", addr, val);
}

void cpu_x86_outw(CPUX86State *env, int addr, int val)
{
    fprintf(stderr, "outw: port=0x%04x, data=%04x\n", addr, val);
}

void cpu_x86_outl(CPUX86State *env, int addr, int val)
{
    fprintf(stderr, "outl: port=0x%04x, data=%08x\n", addr, val);
}

int cpu_x86_inb(CPUX86State *env, int addr)
{
    fprintf(stderr, "inb: port=0x%04x\n", addr);
    return 0;
}

int cpu_x86_inw(CPUX86State *env, int addr)
{
    fprintf(stderr, "inw: port=0x%04x\n", addr);
    return 0;
}

int cpu_x86_inl(CPUX86State *env, int addr)
{
    fprintf(stderr, "inl: port=0x%04x\n", addr);
    return 0;
}

void write_dt(void *ptr, unsigned long addr, unsigned long limit, 
              int seg32_bit)
{
    unsigned int e1, e2, limit_in_pages;
    limit_in_pages = 0;
    if (limit > 0xffff) {
        limit = limit >> 12;
        limit_in_pages = 1;
    }
    e1 = (addr << 16) | (limit & 0xffff);
    e2 = ((addr >> 16) & 0xff) | (addr & 0xff000000) | (limit & 0x000f0000);
    e2 |= limit_in_pages << 23; /* byte granularity */
    e2 |= seg32_bit << 22; /* 32 bit segment */
    stl((uint8_t *)ptr, e1);
    stl((uint8_t *)ptr + 4, e2);
}

uint64_t gdt_table[6];

//#define DEBUG_VM86

static inline int is_revectored(int nr, struct target_revectored_struct *bitmap)
{
    return (tswap32(bitmap->__map[nr >> 5]) >> (nr & 0x1f)) & 1;
}

static inline uint8_t *seg_to_linear(unsigned int seg, unsigned int reg)
{
    return (uint8_t *)((seg << 4) + (reg & 0xffff));
}

static inline void pushw(CPUX86State *env, int val)
{
    env->regs[R_ESP] = (env->regs[R_ESP] & ~0xffff) | 
        ((env->regs[R_ESP] - 2) & 0xffff);
    *(uint16_t *)seg_to_linear(env->segs[R_SS], env->regs[R_ESP]) = val;
}

static inline unsigned int get_vflags(CPUX86State *env)
{
    unsigned int eflags;
    eflags = env->eflags & ~(VM_MASK | RF_MASK | IF_MASK);
    if (eflags & VIF_MASK)
        eflags |= IF_MASK;
    return eflags;
}

void save_v86_state(CPUX86State *env)
{
    TaskState *ts = env->opaque;
#ifdef DEBUG_VM86
    printf("save_v86_state\n");
#endif

    /* put the VM86 registers in the userspace register structure */
    ts->target_v86->regs.eax = tswap32(env->regs[R_EAX]);
    ts->target_v86->regs.ebx = tswap32(env->regs[R_EBX]);
    ts->target_v86->regs.ecx = tswap32(env->regs[R_ECX]);
    ts->target_v86->regs.edx = tswap32(env->regs[R_EDX]);
    ts->target_v86->regs.esi = tswap32(env->regs[R_ESI]);
    ts->target_v86->regs.edi = tswap32(env->regs[R_EDI]);
    ts->target_v86->regs.ebp = tswap32(env->regs[R_EBP]);
    ts->target_v86->regs.esp = tswap32(env->regs[R_ESP]);
    ts->target_v86->regs.eip = tswap32(env->eip);
    ts->target_v86->regs.cs = tswap16(env->segs[R_CS]);
    ts->target_v86->regs.ss = tswap16(env->segs[R_SS]);
    ts->target_v86->regs.ds = tswap16(env->segs[R_DS]);
    ts->target_v86->regs.es = tswap16(env->segs[R_ES]);
    ts->target_v86->regs.fs = tswap16(env->segs[R_FS]);
    ts->target_v86->regs.gs = tswap16(env->segs[R_GS]);
    ts->target_v86->regs.eflags = tswap32(env->eflags);

    /* restore 32 bit registers */
    env->regs[R_EAX] = ts->vm86_saved_regs.eax;
    env->regs[R_EBX] = ts->vm86_saved_regs.ebx;
    env->regs[R_ECX] = ts->vm86_saved_regs.ecx;
    env->regs[R_EDX] = ts->vm86_saved_regs.edx;
    env->regs[R_ESI] = ts->vm86_saved_regs.esi;
    env->regs[R_EDI] = ts->vm86_saved_regs.edi;
    env->regs[R_EBP] = ts->vm86_saved_regs.ebp;
    env->regs[R_ESP] = ts->vm86_saved_regs.esp;
    env->eflags = ts->vm86_saved_regs.eflags;
    env->eip = ts->vm86_saved_regs.eip;
    
    cpu_x86_load_seg(env, R_CS, ts->vm86_saved_regs.cs);
    cpu_x86_load_seg(env, R_SS, ts->vm86_saved_regs.ss);
    cpu_x86_load_seg(env, R_DS, ts->vm86_saved_regs.ds);
    cpu_x86_load_seg(env, R_ES, ts->vm86_saved_regs.es);
    cpu_x86_load_seg(env, R_FS, ts->vm86_saved_regs.fs);
    cpu_x86_load_seg(env, R_GS, ts->vm86_saved_regs.gs);
}

/* return from vm86 mode to 32 bit. The vm86() syscall will return
   'retval' */
static inline void return_to_32bit(CPUX86State *env, int retval)
{
#ifdef DEBUG_VM86
    printf("return_to_32bit: ret=0x%x\n", retval);
#endif
    save_v86_state(env);
    env->regs[R_EAX] = retval;
}

/* handle VM86 interrupt (NOTE: the CPU core currently does not
   support TSS interrupt revectoring, so this code is always executed) */
static void do_int(CPUX86State *env, int intno)
{
    TaskState *ts = env->opaque;
    uint32_t *int_ptr, segoffs;
    
    if (env->segs[R_CS] == TARGET_BIOSSEG)
        goto cannot_handle; /* XXX: I am not sure this is really useful */
    if (is_revectored(intno, &ts->target_v86->int_revectored))
        goto cannot_handle;
    if (intno == 0x21 && is_revectored((env->regs[R_EAX] >> 8) & 0xff, 
                                       &ts->target_v86->int21_revectored))
        goto cannot_handle;
    int_ptr = (uint32_t *)(intno << 2);
    segoffs = tswap32(*int_ptr);
    if ((segoffs >> 16) == TARGET_BIOSSEG)
        goto cannot_handle;
#ifdef DEBUG_VM86
    printf("VM86: emulating int 0x%x. CS:IP=%04x:%04x\n", 
           intno, segoffs >> 16, segoffs & 0xffff);
#endif
    /* save old state */
    pushw(env, get_vflags(env));
    pushw(env, env->segs[R_CS]);
    pushw(env, env->eip);
    /* goto interrupt handler */
    env->eip = segoffs & 0xffff;
    cpu_x86_load_seg(env, R_CS, segoffs >> 16);
    env->eflags &= ~(VIF_MASK | TF_MASK);
    return;
 cannot_handle:
#ifdef DEBUG_VM86
    printf("VM86: return to 32 bits int 0x%x\n", intno);
#endif
    return_to_32bit(env, TARGET_VM86_INTx | (intno << 8));
}

void cpu_loop(struct CPUX86State *env)
{
    int trapnr;
    uint8_t *pc;
    target_siginfo_t info;

    for(;;) {
        trapnr = cpu_x86_exec(env);
        pc = env->seg_cache[R_CS].base + env->eip;
        switch(trapnr) {
        case EXCP0D_GPF:
            if (env->eflags & VM_MASK) {
#ifdef DEBUG_VM86
                printf("VM86 exception %04x:%08x %02x %02x\n",
                       env->segs[R_CS], env->eip, pc[0], pc[1]);
#endif
                /* VM86 mode */
                switch(pc[0]) {
                case 0xcd: /* int */
                    env->eip += 2;
                    do_int(env, pc[1]);
                    break;
                case 0x66:
                    switch(pc[1]) {
                    case 0xfb: /* sti */
                    case 0x9d: /* popf */
                    case 0xcf: /* iret */
                        env->eip += 2;
                        return_to_32bit(env, TARGET_VM86_STI);
                        break;
                    default:
                        goto vm86_gpf;
                    }
                    break;
                case 0xfb: /* sti */
                case 0x9d: /* popf */
                case 0xcf: /* iret */
                    env->eip++;
                    return_to_32bit(env, TARGET_VM86_STI);
                    break;
                default:
                vm86_gpf:
                    /* real VM86 GPF exception */
                    return_to_32bit(env, TARGET_VM86_UNKNOWN);
                    break;
                }
            } else {
                if (pc[0] == 0xcd && pc[1] == 0x80) {
                    /* syscall */
                    env->eip += 2;
                    env->regs[R_EAX] = do_syscall(env, 
                                                  env->regs[R_EAX], 
                                                  env->regs[R_EBX],
                                                  env->regs[R_ECX],
                                                  env->regs[R_EDX],
                                                  env->regs[R_ESI],
                                                  env->regs[R_EDI],
                                                  env->regs[R_EBP]);
                } else {
                    /* XXX: more precise info */
                    info.si_signo = SIGSEGV;
                    info.si_errno = 0;
                    info.si_code = TARGET_SI_KERNEL;
                    info._sifields._sigfault._addr = 0;
                    queue_signal(info.si_signo, &info);
                }
            }
            break;
        case EXCP0E_PAGE:
            info.si_signo = SIGSEGV;
            info.si_errno = 0;
            if (!(env->error_code & 1))
                info.si_code = TARGET_SEGV_MAPERR;
            else
                info.si_code = TARGET_SEGV_ACCERR;
            info._sifields._sigfault._addr = env->cr2;
            queue_signal(info.si_signo, &info);
            break;
        case EXCP00_DIVZ:
            if (env->eflags & VM_MASK) {
                do_int(env, trapnr);
            } else {
                /* division by zero */
                info.si_signo = SIGFPE;
                info.si_errno = 0;
                info.si_code = TARGET_FPE_INTDIV;
                info._sifields._sigfault._addr = env->eip;
                queue_signal(info.si_signo, &info);
            }
            break;
        case EXCP04_INTO:
        case EXCP05_BOUND:
            if (env->eflags & VM_MASK) {
                do_int(env, trapnr);
            } else {
                info.si_signo = SIGSEGV;
                info.si_errno = 0;
                info.si_code = TARGET_SI_KERNEL;
                info._sifields._sigfault._addr = 0;
                queue_signal(info.si_signo, &info);
            }
            break;
        case EXCP06_ILLOP:
            info.si_signo = SIGILL;
            info.si_errno = 0;
            info.si_code = TARGET_ILL_ILLOPN;
            info._sifields._sigfault._addr = env->eip;
            queue_signal(info.si_signo, &info);
            break;
        case EXCP_INTERRUPT:
            /* just indicate that signals should be handled asap */
            break;
        default:
            fprintf(stderr, "qemu: 0x%08lx: unhandled CPU exception 0x%x - aborting\n", 
                    (long)pc, trapnr);
            abort();
        }
        process_pending_signals(env);
    }
}

void usage(void)
{
    printf("qemu version " QEMU_VERSION ", Copyright (c) 2003 Fabrice Bellard\n"
           "usage: qemu [-h] [-d] [-L path] [-s size] program [arguments...]\n"
           "Linux x86 emulator\n"
           "\n"
           "-h        print this help\n"
           "-d        activate log (logfile=%s)\n"
           "-L path   set the x86 elf interpreter prefix (default=%s)\n"
           "-s size   set the x86 stack size in bytes (default=%ld)\n",
           DEBUG_LOGFILE,
           interp_prefix, 
           x86_stack_size);
    _exit(1);
}

/* XXX: currently only used for async signals (see signal.c) */
CPUX86State *global_env;
/* used to free thread contexts */
TaskState *first_task_state;

int main(int argc, char **argv)
{
    const char *filename;
    struct target_pt_regs regs1, *regs = &regs1;
    struct image_info info1, *info = &info1;
    TaskState ts1, *ts = &ts1;
    CPUX86State *env;
    int optind;
    const char *r;
    
    if (argc <= 1)
        usage();

    loglevel = 0;
    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")) {
            loglevel = 1;
        } else if (!strcmp(r, "s")) {
            r = argv[optind++];
            x86_stack_size = strtol(r, (char **)&r, 0);
            if (x86_stack_size <= 0)
                usage();
            if (*r == 'M')
                x86_stack_size *= 1024 * 1024;
            else if (*r == 'k' || *r == 'K')
                x86_stack_size *= 1024;
        } else if (!strcmp(r, "L")) {
            interp_prefix = argv[optind++];
        } else {
            usage();
        }
    }
    if (optind >= argc)
        usage();
    filename = argv[optind];

    /* init debug */
    if (loglevel) {
        logfile = fopen(DEBUG_LOGFILE, "w");
        if (!logfile) {
            perror(DEBUG_LOGFILE);
            _exit(1);
        }
        setvbuf(logfile, NULL, _IOLBF, 0);
    }

    /* Zero out regs */
    memset(regs, 0, sizeof(struct target_pt_regs));

    /* Zero out image_info */
    memset(info, 0, sizeof(struct image_info));

    /* Scan interp_prefix dir for replacement files. */
    init_paths(interp_prefix);

    if (elf_exec(filename, argv+optind, environ, regs, info) != 0) {
	printf("Error loading %s\n", filename);
	_exit(1);
    }
    
    if (loglevel) {
        fprintf(logfile, "start_brk   0x%08lx\n" , info->start_brk);
        fprintf(logfile, "end_code    0x%08lx\n" , info->end_code);
        fprintf(logfile, "start_code  0x%08lx\n" , info->start_code);
        fprintf(logfile, "end_data    0x%08lx\n" , info->end_data);
        fprintf(logfile, "start_stack 0x%08lx\n" , info->start_stack);
        fprintf(logfile, "brk         0x%08lx\n" , info->brk);
        fprintf(logfile, "esp         0x%08lx\n" , regs->esp);
        fprintf(logfile, "eip         0x%08lx\n" , regs->eip);
    }

    target_set_brk((char *)info->brk);
    syscall_init();
    signal_init();

    env = cpu_x86_init();
    global_env = env;

    /* build Task State */
    memset(ts, 0, sizeof(TaskState));
    env->opaque = ts;
    ts->used = 1;
    
    /* linux register setup */
    env->regs[R_EAX] = regs->eax;
    env->regs[R_EBX] = regs->ebx;
    env->regs[R_ECX] = regs->ecx;
    env->regs[R_EDX] = regs->edx;
    env->regs[R_ESI] = regs->esi;
    env->regs[R_EDI] = regs->edi;
    env->regs[R_EBP] = regs->ebp;
    env->regs[R_ESP] = regs->esp;
    env->eip = regs->eip;

    /* linux segment setup */
    env->gdt.base = (void *)gdt_table;
    env->gdt.limit = sizeof(gdt_table) - 1;
    write_dt(&gdt_table[__USER_CS >> 3], 0, 0xffffffff, 1);
    write_dt(&gdt_table[__USER_DS >> 3], 0, 0xffffffff, 1);
    cpu_x86_load_seg(env, R_CS, __USER_CS);
    cpu_x86_load_seg(env, R_DS, __USER_DS);
    cpu_x86_load_seg(env, R_ES, __USER_DS);
    cpu_x86_load_seg(env, R_SS, __USER_DS);
    cpu_x86_load_seg(env, R_FS, __USER_DS);
    cpu_x86_load_seg(env, R_GS, __USER_DS);

    cpu_loop(env);
    /* never exits */
    return 0;
}
Commit	Line	Data
31e31b8a	1	/*
3ef693a0	2	* qemu main
31e31b8a FB	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>
04369ff2	23	#include <string.h>
31e31b8a	24	#include <errno.h>
0ecfa993	25	#include <unistd.h>
31e31b8a	26
3ef693a0	27	#include "qemu.h"
31e31b8a	28
0ecfa993	29	#include "cpu-i386.h"
31e31b8a	30
3ef693a0	31	#define DEBUG_LOGFILE "/tmp/qemu.log"
586314f2 FB	32
	33	FILE *logfile = NULL;
	34	int loglevel;
74cd30b8	35	static const char *interp_prefix = CONFIG_QEMU_PREFIX;
586314f2	36
f801f97e FB	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";
74cd30b8 FB	41
	42	/* for recent libc, we add these dummies symbol which are not declared
	43	when generating a linked object (bug in ld ?) */
	44	#if __GLIBC__ > 2 \|\| (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 3)
	45	long __init_array_start[0];
	46	long __init_array_end[0];
	47	long __fini_array_start[0];
	48	long __fini_array_end[0];
	49	#endif
	50
f801f97e FB	51	#endif
f801f97e FB	52
9de5e440 FB	53	/* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
	54	we allocate a bigger stack. Need a better solution, for example
	55	by remapping the process stack directly at the right place */
	56	unsigned long x86_stack_size = 512 * 1024;
31e31b8a FB	57
	58	void gemu_log(const char *fmt, ...)
	59	{
	60	va_list ap;
	61
	62	va_start(ap, fmt);
	63	vfprintf(stderr, fmt, ap);
	64	va_end(ap);
	65	}
	66
31e31b8a	67	/***********************************************************/
0ecfa993	68	/* CPUX86 core interface */
367e86e8	69
b689bc57	70	void cpu_x86_outb(CPUX86State *env, int addr, int val)
367e86e8 FB	71	{
	72	fprintf(stderr, "outb: port=0x%04x, data=%02x\n", addr, val);
	73	}
	74
b689bc57	75	void cpu_x86_outw(CPUX86State *env, int addr, int val)
367e86e8 FB	76	{
	77	fprintf(stderr, "outw: port=0x%04x, data=%04x\n", addr, val);
	78	}
	79
b689bc57	80	void cpu_x86_outl(CPUX86State *env, int addr, int val)
367e86e8 FB	81	{
	82	fprintf(stderr, "outl: port=0x%04x, data=%08x\n", addr, val);
	83	}
	84
b689bc57	85	int cpu_x86_inb(CPUX86State *env, int addr)
367e86e8 FB	86	{
	87	fprintf(stderr, "inb: port=0x%04x\n", addr);
	88	return 0;
	89	}
	90
b689bc57	91	int cpu_x86_inw(CPUX86State *env, int addr)
367e86e8 FB	92	{
	93	fprintf(stderr, "inw: port=0x%04x\n", addr);
	94	return 0;
	95	}
	96
b689bc57	97	int cpu_x86_inl(CPUX86State *env, int addr)
367e86e8 FB	98	{
	99	fprintf(stderr, "inl: port=0x%04x\n", addr);
	100	return 0;
	101	}
	102
6dbad63e FB	103	void write_dt(void *ptr, unsigned long addr, unsigned long limit,
	104	int seg32_bit)
	105	{
	106	unsigned int e1, e2, limit_in_pages;
	107	limit_in_pages = 0;
	108	if (limit > 0xffff) {
	109	limit = limit >> 12;
	110	limit_in_pages = 1;
	111	}
	112	e1 = (addr << 16) \| (limit & 0xffff);
	113	e2 = ((addr >> 16) & 0xff) \| (addr & 0xff000000) \| (limit & 0x000f0000);
	114	e2 \|= limit_in_pages << 23; /* byte granularity */
	115	e2 \|= seg32_bit << 22; /* 32 bit segment */
	116	stl((uint8_t *)ptr, e1);
	117	stl((uint8_t *)ptr + 4, e2);
	118	}
	119
	120	uint64_t gdt_table[6];
31e31b8a	121
851e67a1 FB	122	//#define DEBUG_VM86
851e67a1 FB	123
bc8a22cc FB	124	static inline int is_revectored(int nr, struct target_revectored_struct *bitmap)
	125	{
	126	return (tswap32(bitmap->__map[nr >> 5]) >> (nr & 0x1f)) & 1;
	127	}
	128
	129	static inline uint8_t *seg_to_linear(unsigned int seg, unsigned int reg)
	130	{
	131	return (uint8_t *)((seg << 4) + (reg & 0xffff));
	132	}
	133
	134	static inline void pushw(CPUX86State *env, int val)
	135	{
	136	env->regs[R_ESP] = (env->regs[R_ESP] & ~0xffff) \|
	137	((env->regs[R_ESP] - 2) & 0xffff);
	138	(uint16_t )seg_to_linear(env->segs[R_SS], env->regs[R_ESP]) = val;
	139	}
	140
	141	static inline unsigned int get_vflags(CPUX86State *env)
	142	{
	143	unsigned int eflags;
	144	eflags = env->eflags & ~(VM_MASK \| RF_MASK \| IF_MASK);
	145	if (eflags & VIF_MASK)
	146	eflags \|= IF_MASK;
	147	return eflags;
	148	}
	149
	150	void save_v86_state(CPUX86State *env)
	151	{
	152	TaskState *ts = env->opaque;
	153	#ifdef DEBUG_VM86
	154	printf("save_v86_state\n");
	155	#endif
	156
	157	/* put the VM86 registers in the userspace register structure */
	158	ts->target_v86->regs.eax = tswap32(env->regs[R_EAX]);
	159	ts->target_v86->regs.ebx = tswap32(env->regs[R_EBX]);
	160	ts->target_v86->regs.ecx = tswap32(env->regs[R_ECX]);
	161	ts->target_v86->regs.edx = tswap32(env->regs[R_EDX]);
	162	ts->target_v86->regs.esi = tswap32(env->regs[R_ESI]);
	163	ts->target_v86->regs.edi = tswap32(env->regs[R_EDI]);
	164	ts->target_v86->regs.ebp = tswap32(env->regs[R_EBP]);
	165	ts->target_v86->regs.esp = tswap32(env->regs[R_ESP]);
	166	ts->target_v86->regs.eip = tswap32(env->eip);
	167	ts->target_v86->regs.cs = tswap16(env->segs[R_CS]);
	168	ts->target_v86->regs.ss = tswap16(env->segs[R_SS]);
	169	ts->target_v86->regs.ds = tswap16(env->segs[R_DS]);
	170	ts->target_v86->regs.es = tswap16(env->segs[R_ES]);
	171	ts->target_v86->regs.fs = tswap16(env->segs[R_FS]);
	172	ts->target_v86->regs.gs = tswap16(env->segs[R_GS]);
	173	ts->target_v86->regs.eflags = tswap32(env->eflags);
	174
	175	/* restore 32 bit registers */
	176	env->regs[R_EAX] = ts->vm86_saved_regs.eax;
	177	env->regs[R_EBX] = ts->vm86_saved_regs.ebx;
	178	env->regs[R_ECX] = ts->vm86_saved_regs.ecx;
	179	env->regs[R_EDX] = ts->vm86_saved_regs.edx;
	180	env->regs[R_ESI] = ts->vm86_saved_regs.esi;
	181	env->regs[R_EDI] = ts->vm86_saved_regs.edi;
	182	env->regs[R_EBP] = ts->vm86_saved_regs.ebp;
	183	env->regs[R_ESP] = ts->vm86_saved_regs.esp;
	184	env->eflags = ts->vm86_saved_regs.eflags;
	185	env->eip = ts->vm86_saved_regs.eip;
	186
	187	cpu_x86_load_seg(env, R_CS, ts->vm86_saved_regs.cs);
188	cpu_x86_load_seg(env, R_SS, ts->vm86_saved_regs.ss);
189	cpu_x86_load_seg(env, R_DS, ts->vm86_saved_regs.ds);
190	cpu_x86_load_seg(env, R_ES, ts->vm86_saved_regs.es);
191	cpu_x86_load_seg(env, R_FS, ts->vm86_saved_regs.fs);
192	cpu_x86_load_seg(env, R_GS, ts->vm86_saved_regs.gs);
193	}
194
195	/* return from vm86 mode to 32 bit. The vm86() syscall will return
196	'retval' */
197	static inline void return_to_32bit(CPUX86State *env, int retval)
198	{
199	#ifdef DEBUG_VM86
200	printf("return_to_32bit: ret=0x%x\n", retval);
201	#endif
202	save_v86_state(env);
203	env->regs[R_EAX] = retval;
204	}
205
206	/* handle VM86 interrupt (NOTE: the CPU core currently does not
207	support TSS interrupt revectoring, so this code is always executed) */
208	static void do_int(CPUX86State *env, int intno)
209	{
210	TaskState *ts = env->opaque;
211	uint32_t *int_ptr, segoffs;
212
213	if (env->segs[R_CS] == TARGET_BIOSSEG)
214	goto cannot_handle; /* XXX: I am not sure this is really useful */
215	if (is_revectored(intno, &ts->target_v86->int_revectored))
216	goto cannot_handle;
217	if (intno == 0x21 && is_revectored((env->regs[R_EAX] >> 8) & 0xff,
218	&ts->target_v86->int21_revectored))
219	goto cannot_handle;
220	int_ptr = (uint32_t *)(intno << 2);
221	segoffs = tswap32(*int_ptr);
222	if ((segoffs >> 16) == TARGET_BIOSSEG)
223	goto cannot_handle;
224	#ifdef DEBUG_VM86
225	printf("VM86: emulating int 0x%x. CS:IP=%04x:%04x\n",
226	intno, segoffs >> 16, segoffs & 0xffff);
227	#endif
228	/* save old state */
229	pushw(env, get_vflags(env));
230	pushw(env, env->segs[R_CS]);
231	pushw(env, env->eip);
232	/* goto interrupt handler */
233	env->eip = segoffs & 0xffff;
234	cpu_x86_load_seg(env, R_CS, segoffs >> 16);
235	env->eflags &= ~(VIF_MASK \| TF_MASK);
236	return;
237	cannot_handle:
238	#ifdef DEBUG_VM86
239	printf("VM86: return to 32 bits int 0x%x\n", intno);
240	#endif
241	return_to_32bit(env, TARGET_VM86_INTx \| (intno << 8));
242	}
243
1b6b029e FB	244	void cpu_loop(struct CPUX86State *env)
1b6b029e FB	245	{
bc8a22cc	246	int trapnr;
9de5e440 FB	247	uint8_t *pc;
9de5e440 FB	248	target_siginfo_t info;
851e67a1	249
1b6b029e	250	for(;;) {
bc8a22cc	251	trapnr = cpu_x86_exec(env);
1b6b029e	252	pc = env->seg_cache[R_CS].base + env->eip;
bc8a22cc	253	switch(trapnr) {
1b6b029e	254	case EXCP0D_GPF:
851e67a1	255	if (env->eflags & VM_MASK) {
851e67a1	256	#ifdef DEBUG_VM86
bc8a22cc FB	257	printf("VM86 exception %04x:%08x %02x %02x\n",
bc8a22cc FB	258	env->segs[R_CS], env->eip, pc[0], pc[1]);
851e67a1 FB	259	#endif
851e67a1 FB	260	/* VM86 mode */
851e67a1 FB	261	switch(pc[0]) {
	262	case 0xcd: /* int */
	263	env->eip += 2;
bc8a22cc FB	264	do_int(env, pc[1]);
	265	break;
	266	case 0x66:
	267	switch(pc[1]) {
	268	case 0xfb: /* sti */
	269	case 0x9d: /* popf */
	270	case 0xcf: /* iret */
	271	env->eip += 2;
	272	return_to_32bit(env, TARGET_VM86_STI);
	273	break;
	274	default:
	275	goto vm86_gpf;
	276	}
	277	break;
	278	case 0xfb: /* sti */
	279	case 0x9d: /* popf */
	280	case 0xcf: /* iret */
	281	env->eip++;
	282	return_to_32bit(env, TARGET_VM86_STI);
851e67a1 FB	283	break;
851e67a1 FB	284	default:
bc8a22cc	285	vm86_gpf:
851e67a1	286	/* real VM86 GPF exception */
bc8a22cc	287	return_to_32bit(env, TARGET_VM86_UNKNOWN);
851e67a1 FB	288	break;
851e67a1 FB	289	}
1b6b029e	290	} else {
851e67a1 FB	291	if (pc[0] == 0xcd && pc[1] == 0x80) {
	292	/* syscall */
	293	env->eip += 2;
	294	env->regs[R_EAX] = do_syscall(env,
	295	env->regs[R_EAX],
	296	env->regs[R_EBX],
	297	env->regs[R_ECX],
	298	env->regs[R_EDX],
	299	env->regs[R_ESI],
	300	env->regs[R_EDI],
	301	env->regs[R_EBP]);
	302	} else {
	303	/* XXX: more precise info */
	304	info.si_signo = SIGSEGV;
	305	info.si_errno = 0;
b689bc57	306	info.si_code = TARGET_SI_KERNEL;
851e67a1 FB	307	info._sifields._sigfault._addr = 0;
	308	queue_signal(info.si_signo, &info);
	309	}
1b6b029e FB	310	}
1b6b029e FB	311	break;
b689bc57 FB	312	case EXCP0E_PAGE:
	313	info.si_signo = SIGSEGV;
	314	info.si_errno = 0;
	315	if (!(env->error_code & 1))
	316	info.si_code = TARGET_SEGV_MAPERR;
	317	else
	318	info.si_code = TARGET_SEGV_ACCERR;
	319	info._sifields._sigfault._addr = env->cr2;
	320	queue_signal(info.si_signo, &info);
	321	break;
9de5e440	322	case EXCP00_DIVZ:
bc8a22cc FB	323	if (env->eflags & VM_MASK) {
	324	do_int(env, trapnr);
	325	} else {
	326	/* division by zero */
	327	info.si_signo = SIGFPE;
	328	info.si_errno = 0;
	329	info.si_code = TARGET_FPE_INTDIV;
	330	info._sifields._sigfault._addr = env->eip;
	331	queue_signal(info.si_signo, &info);
	332	}
9de5e440 FB	333	break;
	334	case EXCP04_INTO:
	335	case EXCP05_BOUND:
bc8a22cc FB	336	if (env->eflags & VM_MASK) {
	337	do_int(env, trapnr);
	338	} else {
	339	info.si_signo = SIGSEGV;
	340	info.si_errno = 0;
b689bc57	341	info.si_code = TARGET_SI_KERNEL;
bc8a22cc FB	342	info._sifields._sigfault._addr = 0;
	343	queue_signal(info.si_signo, &info);
	344	}
9de5e440 FB	345	break;
	346	case EXCP06_ILLOP:
	347	info.si_signo = SIGILL;
	348	info.si_errno = 0;
	349	info.si_code = TARGET_ILL_ILLOPN;
	350	info._sifields._sigfault._addr = env->eip;
	351	queue_signal(info.si_signo, &info);
	352	break;
	353	case EXCP_INTERRUPT:
	354	/* just indicate that signals should be handled asap */
	355	break;
1b6b029e	356	default:
bc8a22cc FB	357	fprintf(stderr, "qemu: 0x%08lx: unhandled CPU exception 0x%x - aborting\n",
bc8a22cc FB	358	(long)pc, trapnr);
1b6b029e FB	359	abort();
1b6b029e FB	360	}
66fb9763	361	process_pending_signals(env);
1b6b029e FB	362	}
	363	}
	364
31e31b8a FB	365	void usage(void)
31e31b8a FB	366	{
3ef693a0	367	printf("qemu version " QEMU_VERSION ", Copyright (c) 2003 Fabrice Bellard\n"
d691f669	368	"usage: qemu [-h] [-d] [-L path] [-s size] program [arguments...]\n"
31e31b8a	369	"Linux x86 emulator\n"
d691f669 FB	370	"\n"
	371	"-h print this help\n"
	372	"-d activate log (logfile=%s)\n"
	373	"-L path set the x86 elf interpreter prefix (default=%s)\n"
	374	"-s size set the x86 stack size in bytes (default=%ld)\n",
	375	DEBUG_LOGFILE,
	376	interp_prefix,
	377	x86_stack_size);
74cd30b8	378	_exit(1);
31e31b8a FB	379	}
31e31b8a FB	380
9de5e440 FB	381	/* XXX: currently only used for async signals (see signal.c) */
9de5e440 FB	382	CPUX86State *global_env;
851e67a1 FB	383	/* used to free thread contexts */
851e67a1 FB	384	TaskState *first_task_state;
9de5e440	385
31e31b8a FB	386	int main(int argc, char **argv)
	387	{
	388	const char *filename;
01ffc75b	389	struct target_pt_regs regs1, *regs = &regs1;
31e31b8a	390	struct image_info info1, *info = &info1;
851e67a1	391	TaskState ts1, *ts = &ts1;
0ecfa993	392	CPUX86State *env;
586314f2	393	int optind;
d691f669 FB	394	const char *r;
d691f669 FB	395
31e31b8a FB	396	if (argc <= 1)
31e31b8a FB	397	usage();
f801f97e	398
586314f2 FB	399	loglevel = 0;
586314f2 FB	400	optind = 1;
d691f669 FB	401	for(;;) {
	402	if (optind >= argc)
	403	break;
	404	r = argv[optind];
	405	if (r[0] != '-')
	406	break;
586314f2	407	optind++;
d691f669 FB	408	r++;
	409	if (!strcmp(r, "-")) {
	410	break;
	411	} else if (!strcmp(r, "d")) {
	412	loglevel = 1;
	413	} else if (!strcmp(r, "s")) {
	414	r = argv[optind++];
	415	x86_stack_size = strtol(r, (char **)&r, 0);
	416	if (x86_stack_size <= 0)
	417	usage();
	418	if (*r == 'M')
	419	x86_stack_size = 1024 1024;
	420	else if (r == 'k' \|\| r == 'K')
	421	x86_stack_size *= 1024;
	422	} else if (!strcmp(r, "L")) {
	423	interp_prefix = argv[optind++];
	424	} else {
	425	usage();
	426	}
586314f2	427	}
d691f669 FB	428	if (optind >= argc)
d691f669 FB	429	usage();
586314f2 FB	430	filename = argv[optind];
	431
	432	/* init debug */
	433	if (loglevel) {
	434	logfile = fopen(DEBUG_LOGFILE, "w");
	435	if (!logfile) {
	436	perror(DEBUG_LOGFILE);
74cd30b8	437	_exit(1);
586314f2 FB	438	}
	439	setvbuf(logfile, NULL, _IOLBF, 0);
	440	}
31e31b8a FB	441
31e31b8a FB	442	/* Zero out regs */
01ffc75b	443	memset(regs, 0, sizeof(struct target_pt_regs));
31e31b8a FB	444
	445	/* Zero out image_info */
	446	memset(info, 0, sizeof(struct image_info));
	447
74cd30b8 FB	448	/* Scan interp_prefix dir for replacement files. */
	449	init_paths(interp_prefix);
	450
	451	if (elf_exec(filename, argv+optind, environ, regs, info) != 0) {
31e31b8a	452	printf("Error loading %s\n", filename);
74cd30b8	453	_exit(1);
31e31b8a FB	454	}
31e31b8a FB	455
4b74fe1f FB	456	if (loglevel) {
	457	fprintf(logfile, "start_brk 0x%08lx\n" , info->start_brk);
	458	fprintf(logfile, "end_code 0x%08lx\n" , info->end_code);
	459	fprintf(logfile, "start_code 0x%08lx\n" , info->start_code);
	460	fprintf(logfile, "end_data 0x%08lx\n" , info->end_data);
	461	fprintf(logfile, "start_stack 0x%08lx\n" , info->start_stack);
	462	fprintf(logfile, "brk 0x%08lx\n" , info->brk);
	463	fprintf(logfile, "esp 0x%08lx\n" , regs->esp);
	464	fprintf(logfile, "eip 0x%08lx\n" , regs->eip);
	465	}
31e31b8a FB	466
	467	target_set_brk((char *)info->brk);
	468	syscall_init();
66fb9763	469	signal_init();
31e31b8a	470
0ecfa993	471	env = cpu_x86_init();
9de5e440	472	global_env = env;
0ecfa993	473
851e67a1 FB	474	/* build Task State */
	475	memset(ts, 0, sizeof(TaskState));
	476	env->opaque = ts;
	477	ts->used = 1;
	478
6dbad63e	479	/* linux register setup */
0ecfa993 FB	480	env->regs[R_EAX] = regs->eax;
	481	env->regs[R_EBX] = regs->ebx;
	482	env->regs[R_ECX] = regs->ecx;
	483	env->regs[R_EDX] = regs->edx;
	484	env->regs[R_ESI] = regs->esi;
	485	env->regs[R_EDI] = regs->edi;
	486	env->regs[R_EBP] = regs->ebp;
	487	env->regs[R_ESP] = regs->esp;
dab2ed99	488	env->eip = regs->eip;
31e31b8a	489
6dbad63e FB	490	/* linux segment setup */
	491	env->gdt.base = (void *)gdt_table;
	492	env->gdt.limit = sizeof(gdt_table) - 1;
	493	write_dt(&gdt_table[__USER_CS >> 3], 0, 0xffffffff, 1);
	494	write_dt(&gdt_table[__USER_DS >> 3], 0, 0xffffffff, 1);
	495	cpu_x86_load_seg(env, R_CS, __USER_CS);
	496	cpu_x86_load_seg(env, R_DS, __USER_DS);
	497	cpu_x86_load_seg(env, R_ES, __USER_DS);
	498	cpu_x86_load_seg(env, R_SS, __USER_DS);
	499	cpu_x86_load_seg(env, R_FS, __USER_DS);
	500	cpu_x86_load_seg(env, R_GS, __USER_DS);
31e31b8a	501
1b6b029e FB	502	cpu_loop(env);
1b6b029e FB	503	/* never exits */
31e31b8a FB	504	return 0;
31e31b8a FB	505	}