Archipelago » qemu

/*

 *  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 "cpu.h"

#include "exec-all.h"

#include "svm.h"

//#define DEBUG_MMU

static int cpu_x86_register (CPUX86State *env, const char *cpu_model);

static void add_flagname_to_bitmaps(char *flagname, uint32_t *features, 

                                    uint32_t *ext_features, 

                                    uint32_t *ext2_features, 

                                    uint32_t *ext3_features)

{

    int i;

    /* feature flags taken from "Intel Processor Identification and the CPUID

     * Instruction" and AMD's "CPUID Specification". In cases of disagreement 

     * about feature names, the Linux name is used. */

    const char *feature_name[] = {

        "fpu", "vme", "de", "pse", "tsc", "msr", "pae", "mce",

        "cx8", "apic", NULL, "sep", "mtrr", "pge", "mca", "cmov",

        "pat", "pse36", "pn" /* Intel psn */, "clflush" /* Intel clfsh */, NULL, "ds" /* Intel dts */, "acpi", "mmx",

        "fxsr", "sse", "sse2", "ss", "ht" /* Intel htt */, "tm", "ia64", "pbe",

    };

    const char *ext_feature_name[] = {

       "pni" /* Intel,AMD sse3 */, NULL, NULL, "monitor", "ds_cpl", "vmx", NULL /* Linux smx */, "est",

       "tm2", "ssse3", "cid", NULL, NULL, "cx16", "xtpr", NULL,

       NULL, NULL, "dca", NULL, NULL, NULL, NULL, "popcnt",

       NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,

    };

    const char *ext2_feature_name[] = {

       "fpu", "vme", "de", "pse", "tsc", "msr", "pae", "mce",

       "cx8" /* AMD CMPXCHG8B */, "apic", NULL, "syscall", "mttr", "pge", "mca", "cmov",

       "pat", "pse36", NULL, NULL /* Linux mp */, "nx" /* Intel xd */, NULL, "mmxext", "mmx",

       "fxsr", "fxsr_opt" /* AMD ffxsr */, "pdpe1gb" /* AMD Page1GB */, "rdtscp", NULL, "lm" /* Intel 64 */, "3dnowext", "3dnow",

    };

    const char *ext3_feature_name[] = {

       "lahf_lm" /* AMD LahfSahf */, "cmp_legacy", "svm", "extapic" /* AMD ExtApicSpace */, "cr8legacy" /* AMD AltMovCr8 */, "abm", "sse4a", "misalignsse",

       "3dnowprefetch", "osvw", NULL /* Linux ibs */, NULL, "skinit", "wdt", NULL, NULL,

       NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,

       NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,

    };

    for ( i = 0 ; i < 32 ; i++ ) 

        if (feature_name[i] && !strcmp (flagname, feature_name[i])) {

            *features |= 1 << i;

            return;

        }

    for ( i = 0 ; i < 32 ; i++ ) 

        if (ext_feature_name[i] && !strcmp (flagname, ext_feature_name[i])) {

            *ext_features |= 1 << i;

            return;

        }

    for ( i = 0 ; i < 32 ; i++ ) 

        if (ext2_feature_name[i] && !strcmp (flagname, ext2_feature_name[i])) {

            *ext2_features |= 1 << i;

            return;

        }

    for ( i = 0 ; i < 32 ; i++ ) 

        if (ext3_feature_name[i] && !strcmp (flagname, ext3_feature_name[i])) {

            *ext3_features |= 1 << i;

            return;

        }

    fprintf(stderr, "CPU feature %s not found\n", flagname);

}

CPUX86State *cpu_x86_init(const char *cpu_model)

{

    CPUX86State *env;

    static int inited;

    env = qemu_mallocz(sizeof(CPUX86State));

    if (!env)

        return NULL;

    cpu_exec_init(env);

    env->cpu_model_str = cpu_model;

    /* init various static tables */

    if (!inited) {

        inited = 1;

        optimize_flags_init();

    }

    if (cpu_x86_register(env, cpu_model) < 0) {

        cpu_x86_close(env);

        return NULL;

    }

    cpu_reset(env);

#ifdef USE_KQEMU

    kqemu_init(env);

#endif

    return env;

}

typedef struct x86_def_t {

    const char *name;

    uint32_t vendor1, vendor2, vendor3;

    int family;

    int model;

    int stepping;

    uint32_t features, ext_features, ext2_features, ext3_features;

    uint32_t xlevel;

} x86_def_t;

#define PPRO_FEATURES (CPUID_FP87 | CPUID_DE | CPUID_PSE | CPUID_TSC | \

          CPUID_MSR | CPUID_MCE | CPUID_CX8 | CPUID_PGE | CPUID_CMOV | \

          CPUID_PAT | CPUID_FXSR | CPUID_MMX | CPUID_SSE | CPUID_SSE2 | \

          CPUID_PAE | CPUID_SEP | CPUID_APIC)

static x86_def_t x86_defs[] = {

#ifdef TARGET_X86_64

    {

        .name = "qemu64",

        .vendor1 = 0x68747541, /* "Auth" */

        .vendor2 = 0x69746e65, /* "enti" */

        .vendor3 = 0x444d4163, /* "cAMD" */

        .family = 6,

        .model = 2,

        .stepping = 3,

        .features = PPRO_FEATURES | 

        /* these features are needed for Win64 and aren't fully implemented */

            CPUID_MTRR | CPUID_CLFLUSH | CPUID_MCA |

        /* this feature is needed for Solaris and isn't fully implemented */

            CPUID_PSE36,

        .ext_features = CPUID_EXT_SSE3,

        .ext2_features = (PPRO_FEATURES & 0x0183F3FF) | 

            CPUID_EXT2_LM | CPUID_EXT2_SYSCALL | CPUID_EXT2_NX,

        .ext3_features = CPUID_EXT3_SVM,

        .xlevel = 0x8000000A,

    },

#endif

    {

        .name = "qemu32",

        .family = 6,

        .model = 3,

        .stepping = 3,

        .features = PPRO_FEATURES,

        .ext_features = CPUID_EXT_SSE3,

        .xlevel = 0,

    },

    {

        .name = "486",

        .family = 4,

        .model = 0,

        .stepping = 0,

        .features = 0x0000000B,

        .xlevel = 0,

    },

    {

        .name = "pentium",

        .family = 5,

        .model = 4,

        .stepping = 3,

        .features = 0x008001BF,

        .xlevel = 0,

    },

    {

        .name = "pentium2",

        .family = 6,

        .model = 5,

        .stepping = 2,

        .features = 0x0183F9FF,

        .xlevel = 0,

    },

    {

        .name = "pentium3",

        .family = 6,

        .model = 7,

        .stepping = 3,

        .features = 0x0383F9FF,

        .xlevel = 0,

    },

};

static int cpu_x86_find_by_name(x86_def_t *x86_cpu_def, const char *cpu_model)

{

    unsigned int i;

    x86_def_t *def;

    char *s = strdup(cpu_model);

    char *featurestr, *name = strtok(s, ",");

    uint32_t plus_features = 0, plus_ext_features = 0, plus_ext2_features = 0, plus_ext3_features = 0;

    uint32_t minus_features = 0, minus_ext_features = 0, minus_ext2_features = 0, minus_ext3_features = 0;

    int family = -1, model = -1, stepping = -1;

    def = NULL;

    for (i = 0; i < sizeof(x86_defs) / sizeof(x86_def_t); i++) {

        if (strcmp(name, x86_defs[i].name) == 0) {

            def = &x86_defs[i];

            break;

        }

    }

    if (!def)

        goto error;

    memcpy(x86_cpu_def, def, sizeof(*def));

    featurestr = strtok(NULL, ",");

    while (featurestr) {

        char *val;

        if (featurestr[0] == '+') {

            add_flagname_to_bitmaps(featurestr + 1, &plus_features, &plus_ext_features, &plus_ext2_features, &plus_ext3_features);

        } else if (featurestr[0] == '-') {

            add_flagname_to_bitmaps(featurestr + 1, &minus_features, &minus_ext_features, &minus_ext2_features, &minus_ext3_features);

        } else if ((val = strchr(featurestr, '='))) {

            *val = 0; val++;

            if (!strcmp(featurestr, "family")) {

                char *err;

                family = strtol(val, &err, 10);

                if (!*val || *err || family < 0) {

                    fprintf(stderr, "bad numerical value %s\n", val);

                    x86_cpu_def = 0;

                    goto error;

                }

                x86_cpu_def->family = family;

            } else if (!strcmp(featurestr, "model")) {

                char *err;

                model = strtol(val, &err, 10);

                if (!*val || *err || model < 0 || model > 0xf) {

                    fprintf(stderr, "bad numerical value %s\n", val);

                    x86_cpu_def = 0;

                    goto error;

                }

                x86_cpu_def->model = model;

            } else if (!strcmp(featurestr, "stepping")) {

                char *err;

                stepping = strtol(val, &err, 10);

                if (!*val || *err || stepping < 0 || stepping > 0xf) {

                    fprintf(stderr, "bad numerical value %s\n", val);

                    x86_cpu_def = 0;

                    goto error;

                }

                x86_cpu_def->stepping = stepping;

            } else {

                fprintf(stderr, "unrecognized feature %s\n", featurestr);

                x86_cpu_def = 0;

                goto error;

            }

        } else {

            fprintf(stderr, "feature string `%s' not in format (+feature|-feature|feature=xyz)\n", featurestr);

            x86_cpu_def = 0;

            goto error;

        }

        featurestr = strtok(NULL, ",");

    }

    x86_cpu_def->features |= plus_features;

    x86_cpu_def->ext_features |= plus_ext_features;

    x86_cpu_def->ext2_features |= plus_ext2_features;

    x86_cpu_def->ext3_features |= plus_ext3_features;

    x86_cpu_def->features &= ~minus_features;

    x86_cpu_def->ext_features &= ~minus_ext_features;

    x86_cpu_def->ext2_features &= ~minus_ext2_features;

    x86_cpu_def->ext3_features &= ~minus_ext3_features;

    free(s);

    return 0;

error:

    free(s);

    return -1;

}

void x86_cpu_list (FILE *f, int (*cpu_fprintf)(FILE *f, const char *fmt, ...))

{

    unsigned int i;

    for (i = 0; i < sizeof(x86_defs) / sizeof(x86_def_t); i++)

        (*cpu_fprintf)(f, "x86 %16s\n", x86_defs[i].name);

}

static int cpu_x86_register (CPUX86State *env, const char *cpu_model)

{

    x86_def_t def1, *def = &def1;

    if (cpu_x86_find_by_name(def, cpu_model) < 0)

        return -1;

    if (def->vendor1) {

        env->cpuid_vendor1 = def->vendor1;

        env->cpuid_vendor2 = def->vendor2;

        env->cpuid_vendor3 = def->vendor3;

    } else {

        env->cpuid_vendor1 = 0x756e6547; /* "Genu" */

        env->cpuid_vendor2 = 0x49656e69; /* "ineI" */

        env->cpuid_vendor3 = 0x6c65746e; /* "ntel" */

    }

    env->cpuid_level = 2;

    env->cpuid_version = (def->family << 8) | (def->model << 4) | def->stepping;

    env->cpuid_features = def->features;

    env->pat = 0x0007040600070406ULL;

    env->cpuid_ext_features = def->ext_features;

    env->cpuid_ext2_features = def->ext2_features;

    env->cpuid_xlevel = def->xlevel;

    env->cpuid_ext3_features = def->ext3_features;

    {

        const char *model_id = "QEMU Virtual CPU version " QEMU_VERSION;

        int c, len, i;

        len = strlen(model_id);

        for(i = 0; i < 48; i++) {

            if (i >= len)

                c = '\0';

            else

                c = model_id[i];

            env->cpuid_model[i >> 2] |= c << (8 * (i & 3));

        }

    }

    return 0;

}

/* NOTE: must be called outside the CPU execute loop */

void cpu_reset(CPUX86State *env)

{

    int i;

    memset(env, 0, offsetof(CPUX86State, breakpoints));

    tlb_flush(env, 1);

    env->old_exception = -1;

    /* init to reset state */

#ifdef CONFIG_SOFTMMU

    env->hflags |= HF_SOFTMMU_MASK;

#endif

    env->hflags |= HF_GIF_MASK;

    cpu_x86_update_cr0(env, 0x60000010);

    env->a20_mask = 0xffffffff;

    env->smbase = 0x30000;

    env->idt.limit = 0xffff;

    env->gdt.limit = 0xffff;

    env->ldt.limit = 0xffff;

    env->ldt.flags = DESC_P_MASK;

    env->tr.limit = 0xffff;

    env->tr.flags = DESC_P_MASK;

    cpu_x86_load_seg_cache(env, R_CS, 0xf000, 0xffff0000, 0xffff, 0);

    cpu_x86_load_seg_cache(env, R_DS, 0, 0, 0xffff, 0);

    cpu_x86_load_seg_cache(env, R_ES, 0, 0, 0xffff, 0);

    cpu_x86_load_seg_cache(env, R_SS, 0, 0, 0xffff, 0);

    cpu_x86_load_seg_cache(env, R_FS, 0, 0, 0xffff, 0);

    cpu_x86_load_seg_cache(env, R_GS, 0, 0, 0xffff, 0);

    env->eip = 0xfff0;

    env->regs[R_EDX] = env->cpuid_version;

    env->eflags = 0x2;

    /* FPU init */

    for(i = 0;i < 8; i++)

        env->fptags[i] = 1;

    env->fpuc = 0x37f;

    env->mxcsr = 0x1f80;

}

void cpu_x86_close(CPUX86State *env)

{

    free(env);

}

/***********************************************************/

/* x86 debug */

static const char *cc_op_str[] = {

    "DYNAMIC",

    "EFLAGS",

    "MULB",

    "MULW",

    "MULL",

    "MULQ",

    "ADDB",

    "ADDW",

    "ADDL",

    "ADDQ",

    "ADCB",

    "ADCW",

    "ADCL",

    "ADCQ",

    "SUBB",

    "SUBW",

    "SUBL",

    "SUBQ",

    "SBBB",

    "SBBW",

    "SBBL",

    "SBBQ",

    "LOGICB",

    "LOGICW",

    "LOGICL",

    "LOGICQ",

    "INCB",

    "INCW",

    "INCL",

    "INCQ",

    "DECB",

    "DECW",

    "DECL",

    "DECQ",

    "SHLB",

    "SHLW",

    "SHLL",

    "SHLQ",

    "SARB",

    "SARW",

    "SARL",

    "SARQ",

};

void cpu_dump_state(CPUState *env, FILE *f,

                    int (*cpu_fprintf)(FILE *f, const char *fmt, ...),

                    int flags)

{

    int eflags, i, nb;

    char cc_op_name[32];

    static const char *seg_name[6] = { "ES", "CS", "SS", "DS", "FS", "GS" };

    eflags = env->eflags;

#ifdef TARGET_X86_64

    if (env->hflags & HF_CS64_MASK) {

        cpu_fprintf(f,

                    "RAX=%016" PRIx64 " RBX=%016" PRIx64 " RCX=%016" PRIx64 " RDX=%016" PRIx64 "\n"

                    "RSI=%016" PRIx64 " RDI=%016" PRIx64 " RBP=%016" PRIx64 " RSP=%016" PRIx64 "\n"

                    "R8 =%016" PRIx64 " R9 =%016" PRIx64 " R10=%016" PRIx64 " R11=%016" PRIx64 "\n"

                    "R12=%016" PRIx64 " R13=%016" PRIx64 " R14=%016" PRIx64 " R15=%016" PRIx64 "\n"

                    "RIP=%016" PRIx64 " RFL=%08x [%c%c%c%c%c%c%c] CPL=%d II=%d A20=%d SMM=%d HLT=%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->regs[8],

                    env->regs[9],

                    env->regs[10],

                    env->regs[11],

                    env->regs[12],

                    env->regs[13],

                    env->regs[14],

                    env->regs[15],

                    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,

                    (env->a20_mask >> 20) & 1,

                    (env->hflags >> HF_SMM_SHIFT) & 1,

                    (env->hflags >> HF_HALTED_SHIFT) & 1);

    } else

#endif

    {

        cpu_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 A20=%d SMM=%d HLT=%d\n",

                    (uint32_t)env->regs[R_EAX],

                    (uint32_t)env->regs[R_EBX],

                    (uint32_t)env->regs[R_ECX],

                    (uint32_t)env->regs[R_EDX],

                    (uint32_t)env->regs[R_ESI],

                    (uint32_t)env->regs[R_EDI],

                    (uint32_t)env->regs[R_EBP],

                    (uint32_t)env->regs[R_ESP],

                    (uint32_t)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,

                    (env->a20_mask >> 20) & 1,

                    (env->hflags >> HF_SMM_SHIFT) & 1,

                    (env->hflags >> HF_HALTED_SHIFT) & 1);

    }

#ifdef TARGET_X86_64

    if (env->hflags & HF_LMA_MASK) {

        for(i = 0; i < 6; i++) {

            SegmentCache *sc = &env->segs[i];

            cpu_fprintf(f, "%s =%04x %016" PRIx64 " %08x %08x\n",

                        seg_name[i],

                        sc->selector,

                        sc->base,

                        sc->limit,

                        sc->flags);

        }

        cpu_fprintf(f, "LDT=%04x %016" PRIx64 " %08x %08x\n",

                    env->ldt.selector,

                    env->ldt.base,

                    env->ldt.limit,

                    env->ldt.flags);

        cpu_fprintf(f, "TR =%04x %016" PRIx64 " %08x %08x\n",

                    env->tr.selector,

                    env->tr.base,

                    env->tr.limit,

                    env->tr.flags);

        cpu_fprintf(f, "GDT=     %016" PRIx64 " %08x\n",

                    env->gdt.base, env->gdt.limit);

        cpu_fprintf(f, "IDT=     %016" PRIx64 " %08x\n",

                    env->idt.base, env->idt.limit);

        cpu_fprintf(f, "CR0=%08x CR2=%016" PRIx64 " CR3=%016" PRIx64 " CR4=%08x\n",

                    (uint32_t)env->cr[0],

                    env->cr[2],

                    env->cr[3],

                    (uint32_t)env->cr[4]);

    } else

#endif

    {

        for(i = 0; i < 6; i++) {

            SegmentCache *sc = &env->segs[i];

            cpu_fprintf(f, "%s =%04x %08x %08x %08x\n",

                        seg_name[i],

                        sc->selector,

                        (uint32_t)sc->base,

                        sc->limit,

                        sc->flags);

        }

        cpu_fprintf(f, "LDT=%04x %08x %08x %08x\n",

                    env->ldt.selector,

                    (uint32_t)env->ldt.base,

                    env->ldt.limit,

                    env->ldt.flags);

        cpu_fprintf(f, "TR =%04x %08x %08x %08x\n",

                    env->tr.selector,

                    (uint32_t)env->tr.base,

                    env->tr.limit,

                    env->tr.flags);

        cpu_fprintf(f, "GDT=     %08x %08x\n",

                    (uint32_t)env->gdt.base, env->gdt.limit);

        cpu_fprintf(f, "IDT=     %08x %08x\n",

                    (uint32_t)env->idt.base, env->idt.limit);

        cpu_fprintf(f, "CR0=%08x CR2=%08x CR3=%08x CR4=%08x\n",

                    (uint32_t)env->cr[0],

                    (uint32_t)env->cr[2],

                    (uint32_t)env->cr[3],

                    (uint32_t)env->cr[4]);

    }

    if (flags & X86_DUMP_CCOP) {

        if ((unsigned)env->cc_op < CC_OP_NB)

            snprintf(cc_op_name, sizeof(cc_op_name), "%s", cc_op_str[env->cc_op]);

        else

            snprintf(cc_op_name, sizeof(cc_op_name), "[%d]", env->cc_op);

#ifdef TARGET_X86_64

        if (env->hflags & HF_CS64_MASK) {

            cpu_fprintf(f, "CCS=%016" PRIx64 " CCD=%016" PRIx64 " CCO=%-8s\n",

                        env->cc_src, env->cc_dst,

                        cc_op_name);

        } else

#endif

        {

            cpu_fprintf(f, "CCS=%08x CCD=%08x CCO=%-8s\n",

                        (uint32_t)env->cc_src, (uint32_t)env->cc_dst,

                        cc_op_name);

        }

    }

    if (flags & X86_DUMP_FPU) {

        int fptag;

        fptag = 0;

        for(i = 0; i < 8; i++) {

            fptag |= ((!env->fptags[i]) << i);

        }

        cpu_fprintf(f, "FCW=%04x FSW=%04x [ST=%d] FTW=%02x MXCSR=%08x\n",

                    env->fpuc,

                    (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11,

                    env->fpstt,

                    fptag,

                    env->mxcsr);

        for(i=0;i<8;i++) {

#if defined(USE_X86LDOUBLE)

            union {

                long double d;

                struct {

                    uint64_t lower;

                    uint16_t upper;

                } l;

            } tmp;

            tmp.d = env->fpregs[i].d;

            cpu_fprintf(f, "FPR%d=%016" PRIx64 " %04x",

                        i, tmp.l.lower, tmp.l.upper);

#else

            cpu_fprintf(f, "FPR%d=%016" PRIx64,

                        i, env->fpregs[i].mmx.q);

#endif

            if ((i & 1) == 1)

                cpu_fprintf(f, "\n");

            else

                cpu_fprintf(f, " ");

        }

        if (env->hflags & HF_CS64_MASK)

            nb = 16;

        else

            nb = 8;

        for(i=0;i<nb;i++) {

            cpu_fprintf(f, "XMM%02d=%08x%08x%08x%08x",

                        i,

                        env->xmm_regs[i].XMM_L(3),

                        env->xmm_regs[i].XMM_L(2),

                        env->xmm_regs[i].XMM_L(1),

                        env->xmm_regs[i].XMM_L(0));

            if ((i & 1) == 1)

                cpu_fprintf(f, "\n");

            else

                cpu_fprintf(f, " ");

        }

    }

}

/***********************************************************/

/* x86 mmu */

/* XXX: add PGE support */

void cpu_x86_set_a20(CPUX86State *env, int a20_state)

{

    a20_state = (a20_state != 0);

    if (a20_state != ((env->a20_mask >> 20) & 1)) {

#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, CPU_INTERRUPT_EXITTB);

        /* when a20 is changed, all the MMU mappings are invalid, so

           we must flush everything */

        tlb_flush(env, 1);

        env->a20_mask = 0xffefffff | (a20_state << 20);

    }

}

void cpu_x86_update_cr0(CPUX86State *env, uint32_t new_cr0)

{

    int pe_state;

#if defined(DEBUG_MMU)

    printf("CR0 update: CR0=0x%08x\n", new_cr0);

#endif

    if ((new_cr0 & (CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK)) !=

        (env->cr[0] & (CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK))) {

        tlb_flush(env, 1);

    }

#ifdef TARGET_X86_64

    if (!(env->cr[0] & CR0_PG_MASK) && (new_cr0 & CR0_PG_MASK) &&

        (env->efer & MSR_EFER_LME)) {

        /* enter in long mode */

        /* XXX: generate an exception */

        if (!(env->cr[4] & CR4_PAE_MASK))

            return;

        env->efer |= MSR_EFER_LMA;

        env->hflags |= HF_LMA_MASK;

    } else if ((env->cr[0] & CR0_PG_MASK) && !(new_cr0 & CR0_PG_MASK) &&

               (env->efer & MSR_EFER_LMA)) {

        /* exit long mode */

        env->efer &= ~MSR_EFER_LMA;

        env->hflags &= ~(HF_LMA_MASK | HF_CS64_MASK);

        env->eip &= 0xffffffff;

    }

#endif

    env->cr[0] = new_cr0 | CR0_ET_MASK;

    /* 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);

    /* update FPU flags */

    env->hflags = (env->hflags & ~(HF_MP_MASK | HF_EM_MASK | HF_TS_MASK)) |

        ((new_cr0 << (HF_MP_SHIFT - 1)) & (HF_MP_MASK | HF_EM_MASK | HF_TS_MASK));

}

/* XXX: in legacy PAE mode, generate a GPF if reserved bits are set in

   the PDPT */

void cpu_x86_update_cr3(CPUX86State *env, target_ulong new_cr3)

{

    env->cr[3] = new_cr3;

    if (env->cr[0] & CR0_PG_MASK) {

#if defined(DEBUG_MMU)

        printf("CR3 update: CR3=" TARGET_FMT_lx "\n", new_cr3);

#endif

        tlb_flush(env, 0);

    }

}

void cpu_x86_update_cr4(CPUX86State *env, uint32_t new_cr4)

{

#if defined(DEBUG_MMU)

    printf("CR4 update: CR4=%08x\n", (uint32_t)env->cr[4]);

#endif

    if ((new_cr4 & (CR4_PGE_MASK | CR4_PAE_MASK | CR4_PSE_MASK)) !=

        (env->cr[4] & (CR4_PGE_MASK | CR4_PAE_MASK | CR4_PSE_MASK))) {

        tlb_flush(env, 1);

    }

    /* SSE handling */

    if (!(env->cpuid_features & CPUID_SSE))

        new_cr4 &= ~CR4_OSFXSR_MASK;

    if (new_cr4 & CR4_OSFXSR_MASK)

        env->hflags |= HF_OSFXSR_MASK;

    else

        env->hflags &= ~HF_OSFXSR_MASK;

    env->cr[4] = new_cr4;

}

/* XXX: also flush 4MB pages */

void cpu_x86_flush_tlb(CPUX86State *env, target_ulong addr)

{

    tlb_flush_page(env, addr);

}

#if defined(CONFIG_USER_ONLY)

int cpu_x86_handle_mmu_fault(CPUX86State *env, target_ulong addr,

                             int is_write, int mmu_idx, int is_softmmu)

{

    /* user mode only emulation */

    is_write &= 1;

    env->cr[2] = addr;

    env->error_code = (is_write << PG_ERROR_W_BIT);

    env->error_code |= PG_ERROR_U_MASK;

    env->exception_index = EXCP0E_PAGE;

    return 1;

}

target_phys_addr_t cpu_get_phys_page_debug(CPUState *env, target_ulong addr)

{

    return addr;

}

#else

#define PHYS_ADDR_MASK 0xfffff000

/* 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, target_ulong addr,

                             int is_write1, int mmu_idx, int is_softmmu)

{

    uint64_t ptep, pte;

    uint32_t pdpe_addr, pde_addr, pte_addr;

    int error_code, is_dirty, prot, page_size, ret, is_write, is_user;

    unsigned long paddr, page_offset;

    target_ulong vaddr, virt_addr;

    is_user = mmu_idx == MMU_USER_IDX;

#if defined(DEBUG_MMU)

    printf("MMU fault: addr=" TARGET_FMT_lx " w=%d u=%d eip=" TARGET_FMT_lx "\n",

           addr, is_write1, is_user, env->eip);

#endif

    is_write = is_write1 & 1;

    if (!(env->cr[0] & CR0_PG_MASK)) {

        pte = addr;

        virt_addr = addr & TARGET_PAGE_MASK;

        prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;