qemu/target-i386/helper2.c
bellard c8135d9af6 fixed subtle bug: in some cases PG_DIRTY was not set correctly
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@547 c046a42c-6fe2-441c-8c8c-71466251a162
2004-01-13 00:00:25 +00:00

387 lines
11 KiB
C

/*
* i386 helpers (without register variable usage)
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include <signal.h>
#include <assert.h>
#include <sys/mman.h>
#include "cpu.h"
#include "exec-all.h"
//#define DEBUG_MMU
CPUX86State *cpu_x86_init(void)
{
CPUX86State *env;
int i;
static int inited;
cpu_exec_init();
env = malloc(sizeof(CPUX86State));
if (!env)
return NULL;
memset(env, 0, sizeof(CPUX86State));
/* basic FPU init */
for(i = 0;i < 8; i++)
env->fptags[i] = 1;
env->fpuc = 0x37f;
/* flags setup : we activate the IRQs by default as in user mode */
env->eflags = 0x2 | IF_MASK;
tlb_flush(env);
#ifdef CONFIG_SOFTMMU
env->hflags |= HF_SOFTMMU_MASK;
#endif
/* init various static tables */
if (!inited) {
inited = 1;
optimize_flags_init();
}
return env;
}
void cpu_x86_close(CPUX86State *env)
{
free(env);
}
/***********************************************************/
/* x86 debug */
static const char *cc_op_str[] = {
"DYNAMIC",
"EFLAGS",
"MULB",
"MULW",
"MULL",
"ADDB",
"ADDW",
"ADDL",
"ADCB",
"ADCW",
"ADCL",
"SUBB",
"SUBW",
"SUBL",
"SBBB",
"SBBW",
"SBBL",
"LOGICB",
"LOGICW",
"LOGICL",
"INCB",
"INCW",
"INCL",
"DECB",
"DECW",
"DECL",
"SHLB",
"SHLW",
"SHLL",
"SARB",
"SARW",
"SARL",
};
void cpu_x86_dump_state(CPUX86State *env, FILE *f, int flags)
{
int eflags, i;
char cc_op_name[32];
static const char *seg_name[6] = { "ES", "CS", "SS", "DS", "FS", "GS" };
eflags = env->eflags;
fprintf(f, "EAX=%08x EBX=%08x ECX=%08x EDX=%08x\n"
"ESI=%08x EDI=%08x EBP=%08x ESP=%08x\n"
"EIP=%08x EFL=%08x [%c%c%c%c%c%c%c] CPL=%d II=%d\n",
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], env->regs[R_ESP],
env->eip, eflags,
eflags & DF_MASK ? 'D' : '-',
eflags & CC_O ? 'O' : '-',
eflags & CC_S ? 'S' : '-',
eflags & CC_Z ? 'Z' : '-',
eflags & CC_A ? 'A' : '-',
eflags & CC_P ? 'P' : '-',
eflags & CC_C ? 'C' : '-',
env->hflags & HF_CPL_MASK,
(env->hflags >> HF_INHIBIT_IRQ_SHIFT) & 1);
for(i = 0; i < 6; i++) {
SegmentCache *sc = &env->segs[i];
fprintf(f, "%s =%04x %08x %08x %08x\n",
seg_name[i],
sc->selector,
(int)sc->base,
sc->limit,
sc->flags);
}
fprintf(f, "LDT=%04x %08x %08x %08x\n",
env->ldt.selector,
(int)env->ldt.base,
env->ldt.limit,
env->ldt.flags);
fprintf(f, "TR =%04x %08x %08x %08x\n",
env->tr.selector,
(int)env->tr.base,
env->tr.limit,
env->tr.flags);
fprintf(f, "GDT= %08x %08x\n",
(int)env->gdt.base, env->gdt.limit);
fprintf(f, "IDT= %08x %08x\n",
(int)env->idt.base, env->idt.limit);
fprintf(f, "CR0=%08x CR2=%08x CR3=%08x CR4=%08x\n",
env->cr[0], env->cr[2], env->cr[3], env->cr[4]);
if (flags & X86_DUMP_CCOP) {
if ((unsigned)env->cc_op < CC_OP_NB)
strcpy(cc_op_name, cc_op_str[env->cc_op]);
else
snprintf(cc_op_name, sizeof(cc_op_name), "[%d]", env->cc_op);
fprintf(f, "CCS=%08x CCD=%08x CCO=%-8s\n",
env->cc_src, env->cc_dst, cc_op_name);
}
if (flags & X86_DUMP_FPU) {
fprintf(f, "ST0=%f ST1=%f ST2=%f ST3=%f\n",
(double)env->fpregs[0],
(double)env->fpregs[1],
(double)env->fpregs[2],
(double)env->fpregs[3]);
fprintf(f, "ST4=%f ST5=%f ST6=%f ST7=%f\n",
(double)env->fpregs[4],
(double)env->fpregs[5],
(double)env->fpregs[7],
(double)env->fpregs[8]);
}
}
/***********************************************************/
/* x86 mmu */
/* XXX: add PGE support */
/* called when cr3 or PG bit are modified */
static int last_pg_state = -1;
static uint32_t a20_mask;
int a20_enabled;
void cpu_x86_set_a20(CPUX86State *env, int a20_state)
{
a20_state = (a20_state != 0);
if (a20_state != a20_enabled) {
#if defined(DEBUG_MMU)
printf("A20 update: a20=%d\n", a20_state);
#endif
/* if the cpu is currently executing code, we must unlink it and
all the potentially executing TB */
cpu_interrupt(env, 0);
/* when a20 is changed, all the MMU mappings are invalid, so
we must flush everything */
tlb_flush(env);
a20_enabled = a20_state;
if (a20_enabled)
a20_mask = 0xffffffff;
else
a20_mask = 0xffefffff;
}
}
void cpu_x86_update_cr0(CPUX86State *env)
{
int pg_state, pe_state;
#if defined(DEBUG_MMU)
printf("CR0 update: CR0=0x%08x\n", env->cr[0]);
#endif
pg_state = env->cr[0] & CR0_PG_MASK;
if (pg_state != last_pg_state) {
tlb_flush(env);
last_pg_state = pg_state;
}
/* update PE flag in hidden flags */
pe_state = (env->cr[0] & CR0_PE_MASK);
env->hflags = (env->hflags & ~HF_PE_MASK) | (pe_state << HF_PE_SHIFT);
/* ensure that ADDSEG is always set in real mode */
env->hflags |= ((pe_state ^ 1) << HF_ADDSEG_SHIFT);
}
void cpu_x86_update_cr3(CPUX86State *env)
{
if (env->cr[0] & CR0_PG_MASK) {
#if defined(DEBUG_MMU)
printf("CR3 update: CR3=%08x\n", env->cr[3]);
#endif
tlb_flush(env);
}
}
void cpu_x86_init_mmu(CPUX86State *env)
{
a20_enabled = 1;
a20_mask = 0xffffffff;
last_pg_state = -1;
cpu_x86_update_cr0(env);
}
/* XXX: also flush 4MB pages */
void cpu_x86_flush_tlb(CPUX86State *env, uint32_t addr)
{
tlb_flush_page(env, addr);
}
/* return value:
-1 = cannot handle fault
0 = nothing more to do
1 = generate PF fault
2 = soft MMU activation required for this block
*/
int cpu_x86_handle_mmu_fault(CPUX86State *env, uint32_t addr,
int is_write, int is_user, int is_softmmu)
{
uint8_t *pde_ptr, *pte_ptr;
uint32_t pde, pte, virt_addr;
int error_code, is_dirty, prot, page_size, ret;
unsigned long paddr, vaddr, page_offset;
#if defined(DEBUG_MMU)
printf("MMU fault: addr=0x%08x w=%d u=%d eip=%08x\n",
addr, is_write, is_user, env->eip);
#endif
if (env->user_mode_only) {
/* user mode only emulation */
error_code = 0;
goto do_fault;
}
if (!(env->cr[0] & CR0_PG_MASK)) {
pte = addr;
virt_addr = addr & TARGET_PAGE_MASK;
prot = PROT_READ | PROT_WRITE;
page_size = 4096;
goto do_mapping;
}
/* page directory entry */
pde_ptr = phys_ram_base +
(((env->cr[3] & ~0xfff) + ((addr >> 20) & ~3)) & a20_mask);
pde = ldl_raw(pde_ptr);
if (!(pde & PG_PRESENT_MASK)) {
error_code = 0;
goto do_fault;
}
if (is_user) {
if (!(pde & PG_USER_MASK))
goto do_fault_protect;
if (is_write && !(pde & PG_RW_MASK))
goto do_fault_protect;
} else {
if ((env->cr[0] & CR0_WP_MASK) && (pde & PG_USER_MASK) &&
is_write && !(pde & PG_RW_MASK))
goto do_fault_protect;
}
/* if PSE bit is set, then we use a 4MB page */
if ((pde & PG_PSE_MASK) && (env->cr[4] & CR4_PSE_MASK)) {
is_dirty = is_write && !(pde & PG_DIRTY_MASK);
if (!(pde & PG_ACCESSED_MASK)) {
pde |= PG_ACCESSED_MASK;
if (is_dirty)
pde |= PG_DIRTY_MASK;
stl_raw(pde_ptr, pde);
}
pte = pde & ~0x003ff000; /* align to 4MB */
page_size = 4096 * 1024;
virt_addr = addr & ~0x003fffff;
} else {
if (!(pde & PG_ACCESSED_MASK)) {
pde |= PG_ACCESSED_MASK;
stl_raw(pde_ptr, pde);
}
/* page directory entry */
pte_ptr = phys_ram_base +
(((pde & ~0xfff) + ((addr >> 10) & 0xffc)) & a20_mask);
pte = ldl_raw(pte_ptr);
if (!(pte & PG_PRESENT_MASK)) {
error_code = 0;
goto do_fault;
}
if (is_user) {
if (!(pte & PG_USER_MASK))
goto do_fault_protect;
if (is_write && !(pte & PG_RW_MASK))
goto do_fault_protect;
} else {
if ((env->cr[0] & CR0_WP_MASK) && (pte & PG_USER_MASK) &&
is_write && !(pte & PG_RW_MASK))
goto do_fault_protect;
}
is_dirty = is_write && !(pte & PG_DIRTY_MASK);
if (!(pte & PG_ACCESSED_MASK) || is_dirty) {
pte |= PG_ACCESSED_MASK;
if (is_dirty)
pte |= PG_DIRTY_MASK;
stl_raw(pte_ptr, pte);
}
page_size = 4096;
virt_addr = addr & ~0xfff;
}
/* the page can be put in the TLB */
prot = PROT_READ;
if (pte & PG_DIRTY_MASK) {
/* only set write access if already dirty... otherwise wait
for dirty access */
if (is_user) {
if (pte & PG_RW_MASK)
prot |= PROT_WRITE;
} else {
if (!(env->cr[0] & CR0_WP_MASK) || !(pte & PG_USER_MASK) ||
(pte & PG_RW_MASK))
prot |= PROT_WRITE;
}
}
do_mapping:
pte = pte & a20_mask;
/* Even if 4MB pages, we map only one 4KB page in the cache to
avoid filling it too fast */
page_offset = (addr & TARGET_PAGE_MASK) & (page_size - 1);
paddr = (pte & TARGET_PAGE_MASK) + page_offset;
vaddr = virt_addr + page_offset;
ret = tlb_set_page(env, vaddr, paddr, prot, is_user, is_softmmu);
return ret;
do_fault_protect:
error_code = PG_ERROR_P_MASK;
do_fault:
env->cr[2] = addr;
env->error_code = (is_write << PG_ERROR_W_BIT) | error_code;
if (is_user)
env->error_code |= PG_ERROR_U_MASK;
return 1;
}