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better vm86 support

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git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@69 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
bellard 2003-03-30 21:02:40 +00:00
parent f631ef9bd2
commit bc8a22cc30
7 changed files with 239 additions and 89 deletions
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33
Changelog
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@ -1,8 +1,41 @@
version 0.1.4:
- more accurate VM86 emulation (can launch small DOS 16 bit
executables in wine).
- fixed push/pop fs/gs
- added iret instruction.
version 0.1.3:
- S390 support (Ulrich Weigand)
- glibc 2.3.x compile fix (Ulrich Weigand)
- socketcall endian fix (Ulrich Weigand)
- struct sockaddr endian fix (Ulrich Weigand)
- sendmsg/recvmsg endian fix (Ulrich Weigand)
- execve endian fix (Ulrich Weigand)
- fdset endian fix (Ulrich Weigand)
- partial setsockopt syscall support (Ulrich Weigand)
- more accurate pushf/popf emulation
- first partial vm86() syscall support (can be used with runcom example).
- added bound, cmpxchg8b, cpuid instructions
- added 16 bit addressing support/override for string operations
- poll() fix
version 0.1.2:
- compile fixes
- xlat instruction
- xchg instruction memory lock
- added simple vm86 example (not working with QEMU yet). The 54 byte
DOS executable 'pi_10.com' program was released by Bertram
Felgenhauer (more information at http://www.boo.net/~jasonp/pipage.html).
version 0.1.1:
- glibc 2.2 compilation fixes
- added -s and -L options
- binary distribution of x86 glibc and wine
- big endian fixes in ELF loader and getdents.
version 0.1:

5
TODO
View File

@ -1,10 +1,11 @@
- fix thread locks
- fix thread stack liberation
- fix x86 stack allocation
- optimize translated cache chaining (DLL PLT-like system)
- more syscalls (in particular all 64 bit ones, IPCs, fix 64 bit
issues, fix 16 bit uid issues)
- finish signal handing (fp87 state, more siginfo conversions)
- verify thread support (clone() and various locks)
- vm86 syscall support
- overrides/16bit for string ops
- make it self runnable (use same trick as ld.so : include its own relocator and libc)
- improved 16 bit support
- fix FPU exceptions (in particular: gen_op_fpush not before mem load)

36
cpu-i386.h
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@ -68,24 +68,24 @@
#define VIP_MASK 0x00100000
#define ID_MASK 0x00200000
#define EXCP00_DIVZ 1
#define EXCP01_SSTP 2
#define EXCP02_NMI 3
#define EXCP03_INT3 4
#define EXCP04_INTO 5
#define EXCP05_BOUND 6
#define EXCP06_ILLOP 7
#define EXCP07_PREX 8
#define EXCP08_DBLE 9
#define EXCP09_XERR 10
#define EXCP0A_TSS 11
#define EXCP0B_NOSEG 12
#define EXCP0C_STACK 13
#define EXCP0D_GPF 14
#define EXCP0E_PAGE 15
#define EXCP10_COPR 17
#define EXCP11_ALGN 18
#define EXCP12_MCHK 19
#define EXCP00_DIVZ 0
#define EXCP01_SSTP 1
#define EXCP02_NMI 2
#define EXCP03_INT3 3
#define EXCP04_INTO 4
#define EXCP05_BOUND 5
#define EXCP06_ILLOP 6
#define EXCP07_PREX 7
#define EXCP08_DBLE 8
#define EXCP09_XERR 9
#define EXCP0A_TSS 10
#define EXCP0B_NOSEG 11
#define EXCP0C_STACK 12
#define EXCP0D_GPF 13
#define EXCP0E_PAGE 14
#define EXCP10_COPR 16
#define EXCP11_ALGN 17
#define EXCP12_MCHK 18
#define EXCP_INTERRUPT 256 /* async interruption */

231
linux-user/main.c
View File

@ -106,77 +106,172 @@ 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 err;
int trapnr;
uint8_t *pc;
target_siginfo_t info;
for(;;) {
err = cpu_x86_exec(env);
trapnr = cpu_x86_exec(env);
pc = env->seg_cache[R_CS].base + env->eip;
switch(err) {
switch(trapnr) {
case EXCP0D_GPF:
if (env->eflags & VM_MASK) {
TaskState *ts;
int ret;
#ifdef DEBUG_VM86
printf("VM86 exception %04x:%08x %02x\n",
env->segs[R_CS], env->eip, pc[0]);
printf("VM86 exception %04x:%08x %02x %02x\n",
env->segs[R_CS], env->eip, pc[0], pc[1]);
#endif
/* VM86 mode */
ts = env->opaque;
/* XXX: add all cases */
switch(pc[0]) {
case 0xcd: /* int */
env->eip += 2;
ret = TARGET_VM86_INTx | (pc[1] << 8);
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 */
ret = TARGET_VM86_UNKNOWN;
return_to_32bit(env, TARGET_VM86_UNKNOWN);
break;
}
#ifdef DEBUG_VM86
printf("ret=0x%x\n", ret);
#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]);
/* restore 32 bit registers */
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);
env->regs[R_EAX] = ret;
} else {
if (pc[0] == 0xcd && pc[1] == 0x80) {
/* syscall */
@ -200,20 +295,28 @@ void cpu_loop(struct CPUX86State *env)
}
break;
case EXCP00_DIVZ:
/* 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);
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:
info.si_signo = SIGSEGV;
info.si_errno = 0;
info.si_code = 0;
info._sifields._sigfault._addr = 0;
queue_signal(info.si_signo, &info);
if (env->eflags & VM_MASK) {
do_int(env, trapnr);
} else {
info.si_signo = SIGSEGV;
info.si_errno = 0;
info.si_code = 0;
info._sifields._sigfault._addr = 0;
queue_signal(info.si_signo, &info);
}
break;
case EXCP06_ILLOP:
info.si_signo = SIGILL;
@ -226,8 +329,8 @@ void cpu_loop(struct CPUX86State *env)
/* just indicate that signals should be handled asap */
break;
default:
fprintf(stderr, "0x%08lx: Unknown exception CPU %d, aborting\n",
(long)pc, err);
fprintf(stderr, "qemu: 0x%08lx: unhandled CPU exception 0x%x - aborting\n",
(long)pc, trapnr);
abort();
}
process_pending_signals(env);

1
linux-user/qemu.h
View File

@ -74,5 +74,6 @@ void cpu_loop(CPUX86State *env);
void process_pending_signals(void *cpu_env);
void signal_init(void);
int queue_signal(int sig, target_siginfo_t *info);
void save_v86_state(CPUX86State *env);
#endif

17
linux-user/signal.c
View File

@ -198,7 +198,7 @@ void __attribute((noreturn)) force_sig(int sig)
{
int host_sig;
host_sig = target_to_host_signal(sig);
fprintf(stderr, "gemu: uncaught target signal %d (%s) - exiting\n",
fprintf(stderr, "qemu: uncaught target signal %d (%s) - exiting\n",
sig, strsignal(host_sig));
#if 1
_exit(-host_sig);
@ -223,7 +223,7 @@ int queue_signal(int sig, target_siginfo_t *info)
target_ulong handler;
#if defined(DEBUG_SIGNAL)
fprintf(stderr, "queue_sigal: sig=%d\n",
fprintf(stderr, "queue_signal: sig=%d\n",
sig);
#endif
k = &sigact_table[sig - 1];
@ -317,7 +317,7 @@ static void host_signal_handler(int host_signum, siginfo_t *info,
if (sig < 1 || sig > TARGET_NSIG)
return;
#if defined(DEBUG_SIGNAL)
fprintf(stderr, "gemu: got signal %d\n", sig);
fprintf(stderr, "qemu: got signal %d\n", sig);
dump_regs(puc);
#endif
host_to_target_siginfo_noswap(&tinfo, info);
@ -538,7 +538,6 @@ setup_sigcontext(struct target_sigcontext *sc, struct target_fpstate *fpstate,
/* non-iBCS2 extensions.. */
err |= __put_user(mask, &sc->oldmask);
err |= __put_user(/*current->thread.cr2*/ 0, &sc->cr2);
return err;
}
@ -859,7 +858,7 @@ void process_pending_signals(void *cpu_env)
handle_signal:
#ifdef DEBUG_SIGNAL
fprintf(stderr, "gemu: process signal %d\n", sig);
fprintf(stderr, "qemu: process signal %d\n", sig);
#endif
/* dequeue signal */
q = k->first;
@ -893,6 +892,14 @@ void process_pending_signals(void *cpu_env)
end of the signal execution (see do_sigreturn) */
host_to_target_sigset(&target_old_set, &old_set);
/* if the CPU is in VM86 mode, we restore the 32 bit values */
#ifdef TARGET_I386
{
CPUX86State *env = cpu_env;
if (env->eflags & VM_MASK)
save_v86_state(env);
}
#endif
/* prepare the stack frame of the virtual CPU */
if (k->sa.sa_flags & TARGET_SA_SIGINFO)
setup_rt_frame(sig, k, &q->info, &target_old_set, cpu_env);

5
syscall-i386.h
View File

@ -755,6 +755,11 @@ struct target_modify_ldt_ldt_s {
unsigned int flags;
};
/* vm86 defines */
#define TARGET_BIOSSEG 0x0f000
#define TARGET_VM86_SIGNAL 0 /* return due to signal */
#define TARGET_VM86_UNKNOWN 1 /* unhandled GP fault - IO-instruction or similar */
#define TARGET_VM86_INTx 2 /* int3/int x instruction (ARG = x) */