kqemu.c

   1 /*
   2  *  KQEMU support
   3  *
   4  *  Copyright (c) 2005 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library 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 GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20 #include "config.h"
  21 #ifdef _WIN32
  22 #include <windows.h>
  23 #include <winioctl.h>
  24 #else
  25 #include <sys/types.h>
  26 #include <sys/mman.h>
  27 #include <sys/ioctl.h>
  28 #endif
  29 #include <stdlib.h>
  30 #include <stdio.h>
  31 #include <stdarg.h>
  32 #include <string.h>
  33 #include <errno.h>
  34 #include <unistd.h>
  35 #include <inttypes.h>
  36
  37 #include "cpu.h"
  38 #include "exec-all.h"
  39
  40 #ifdef USE_KQEMU
  41
  42 #define DEBUG
  43 //#define PROFILE
  44
  45 #include <unistd.h>
  46 #include <fcntl.h>
  47 #include "kqemu/kqemu.h"
  48
  49 /* compatibility stuff */
  50 #ifndef KQEMU_RET_SYSCALL
  51 #define KQEMU_RET_SYSCALL   0x0300 /* syscall insn */
  52 #endif
  53 #ifndef KQEMU_MAX_RAM_PAGES_TO_UPDATE
  54 #define KQEMU_MAX_RAM_PAGES_TO_UPDATE 512
  55 #define KQEMU_RAM_PAGES_UPDATE_ALL (KQEMU_MAX_RAM_PAGES_TO_UPDATE + 1)
  56 #endif
  57
  58 #ifdef _WIN32
  59 #define KQEMU_DEVICE "\\\\.\\kqemu"
  60 #else
  61 #define KQEMU_DEVICE "/dev/kqemu"
  62 #endif
  63
  64 #ifdef _WIN32
  65 #define KQEMU_INVALID_FD INVALID_HANDLE_VALUE
  66 HANDLE kqemu_fd = KQEMU_INVALID_FD;
  67 #define kqemu_closefd(x) CloseHandle(x)
  68 #else
  69 #define KQEMU_INVALID_FD -1
  70 int kqemu_fd = KQEMU_INVALID_FD;
  71 #define kqemu_closefd(x) close(x)
  72 #endif
  73
  74 int kqemu_allowed = 1;
  75 unsigned long *pages_to_flush;
  76 unsigned int nb_pages_to_flush;
  77 unsigned long *ram_pages_to_update;
  78 unsigned int nb_ram_pages_to_update;
  79 extern uint32_t **l1_phys_map;
  80
  81 #define cpuid(index, eax, ebx, ecx, edx) \
  82   asm volatile ("cpuid" \
  83                 : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) \
  84                 : "0" (index))
  85
  86 #ifdef __x86_64__
  87 static int is_cpuid_supported(void)
  88 {
  89     return 1;
  90 }
  91 #else
  92 static int is_cpuid_supported(void)
  93 {
  94     int v0, v1;
  95     asm volatile ("pushf\n"
  96                   "popl %0\n"
  97                   "movl %0, %1\n"
  98                   "xorl $0x00200000, %0\n"
  99                   "pushl %0\n"
 100                   "popf\n"
 101                   "pushf\n"
 102                   "popl %0\n"
 103                   : "=a" (v0), "=d" (v1)
 104                   :
 105                   : "cc");
 106     return (v0 != v1);
 107 }
 108 #endif
 109
 110 static void kqemu_update_cpuid(CPUState *env)
 111 {
 112     int critical_features_mask, features;
 113     uint32_t eax, ebx, ecx, edx;
 114
 115     /* the following features are kept identical on the host and
 116        target cpus because they are important for user code. Strictly
 117        speaking, only SSE really matters because the OS must support
 118        it if the user code uses it. */
 119     critical_features_mask =
 120         CPUID_CMOV | CPUID_CX8 |
 121         CPUID_FXSR | CPUID_MMX | CPUID_SSE |
 122         CPUID_SSE2 | CPUID_SEP;
 123     if (!is_cpuid_supported()) {
 124         features = 0;
 125     } else {
 126         cpuid(1, eax, ebx, ecx, edx);
 127         features = edx;
 128     }
 129 #ifdef __x86_64__
 130     /* NOTE: on x86_64 CPUs, SYSENTER is not supported in
 131        compatibility mode, so in order to have the best performances
 132        it is better not to use it */
 133     features &= ~CPUID_SEP;
 134 #endif
 135     env->cpuid_features = (env->cpuid_features & ~critical_features_mask) |
 136         (features & critical_features_mask);
 137     /* XXX: we could update more of the target CPUID state so that the
 138        non accelerated code sees exactly the same CPU features as the
 139        accelerated code */
 140 }
 141
 142 int kqemu_init(CPUState *env)
 143 {
 144     struct kqemu_init init;
 145     int ret, version;
 146 #ifdef _WIN32
 147     DWORD temp;
 148 #endif
 149
 150     if (!kqemu_allowed)
 151         return -1;
 152
 153 #ifdef _WIN32
 154     kqemu_fd = CreateFile(KQEMU_DEVICE, GENERIC_WRITE | GENERIC_READ,
 155                           FILE_SHARE_READ | FILE_SHARE_WRITE,
 156                           NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL,
 157                           NULL);
 158 #else
 159     kqemu_fd = open(KQEMU_DEVICE, O_RDWR);
 160 #endif
 161     if (kqemu_fd == KQEMU_INVALID_FD) {
 162         fprintf(stderr, "Could not open '%s' - QEMU acceleration layer not activated\n", KQEMU_DEVICE);
 163         return -1;
 164     }
 165     version = 0;
 166 #ifdef _WIN32
 167     DeviceIoControl(kqemu_fd, KQEMU_GET_VERSION, NULL, 0,
 168                     &version, sizeof(version), &temp, NULL);
 169 #else
 170     ioctl(kqemu_fd, KQEMU_GET_VERSION, &version);
 171 #endif
 172     if (version != KQEMU_VERSION) {
 173         fprintf(stderr, "Version mismatch between kqemu module and qemu (%08x %08x) - disabling kqemu use\n",
 174                 version, KQEMU_VERSION);
 175         goto fail;
 176     }
 177
 178     pages_to_flush = qemu_vmalloc(KQEMU_MAX_PAGES_TO_FLUSH *
 179                                   sizeof(unsigned long));
 180     if (!pages_to_flush)
 181         goto fail;
 182
 183     ram_pages_to_update = qemu_vmalloc(KQEMU_MAX_RAM_PAGES_TO_UPDATE *
 184                                        sizeof(unsigned long));
 185     if (!ram_pages_to_update)
 186         goto fail;
 187
 188     init.ram_base = phys_ram_base;
 189     init.ram_size = phys_ram_size;
 190     init.ram_dirty = phys_ram_dirty;
 191     init.phys_to_ram_map = l1_phys_map;
 192     init.pages_to_flush = pages_to_flush;
 193 #if KQEMU_VERSION >= 0x010200
 194     init.ram_pages_to_update = ram_pages_to_update;
 195 #endif
 196 #ifdef _WIN32
 197     ret = DeviceIoControl(kqemu_fd, KQEMU_INIT, &init, sizeof(init),
 198                           NULL, 0, &temp, NULL) == TRUE ? 0 : -1;
 199 #else
 200     ret = ioctl(kqemu_fd, KQEMU_INIT, &init);
 201 #endif
 202     if (ret < 0) {
 203         fprintf(stderr, "Error %d while initializing QEMU acceleration layer - disabling it for now\n", ret);
 204     fail:
 205         kqemu_closefd(kqemu_fd);
 206         kqemu_fd = KQEMU_INVALID_FD;
 207         return -1;
 208     }
 209     kqemu_update_cpuid(env);
 210     env->kqemu_enabled = 1;
 211     nb_pages_to_flush = 0;
 212     nb_ram_pages_to_update = 0;
 213     return 0;
 214 }
 215
 216 void kqemu_flush_page(CPUState *env, target_ulong addr)
 217 {
 218 #ifdef DEBUG
 219     if (loglevel & CPU_LOG_INT) {
 220         fprintf(logfile, "kqemu_flush_page: addr=" TARGET_FMT_lx "\n", addr);
 221     }
 222 #endif
 223     if (nb_pages_to_flush >= KQEMU_MAX_PAGES_TO_FLUSH)
 224         nb_pages_to_flush = KQEMU_FLUSH_ALL;
 225     else
 226         pages_to_flush[nb_pages_to_flush++] = addr;
 227 }
 228
 229 void kqemu_flush(CPUState *env, int global)
 230 {
 231 #ifdef DEBUG
 232     if (loglevel & CPU_LOG_INT) {
 233         fprintf(logfile, "kqemu_flush:\n");
 234     }
 235 #endif
 236     nb_pages_to_flush = KQEMU_FLUSH_ALL;
 237 }
 238
 239 void kqemu_set_notdirty(CPUState *env, ram_addr_t ram_addr)
 240 {
 241 #ifdef DEBUG
 242     if (loglevel & CPU_LOG_INT) {
 243         fprintf(logfile, "kqemu_set_notdirty: addr=%08lx\n", ram_addr);
 244     }
 245 #endif
 246     /* we only track transitions to dirty state */
 247     if (phys_ram_dirty[ram_addr >> TARGET_PAGE_BITS] != 0xff)
 248         return;
 249     if (nb_ram_pages_to_update >= KQEMU_MAX_RAM_PAGES_TO_UPDATE)
 250         nb_ram_pages_to_update = KQEMU_RAM_PAGES_UPDATE_ALL;
 251     else
 252         ram_pages_to_update[nb_ram_pages_to_update++] = ram_addr;
 253 }
 254
 255 struct fpstate {
 256     uint16_t fpuc;
 257     uint16_t dummy1;
 258     uint16_t fpus;
 259     uint16_t dummy2;
 260     uint16_t fptag;
 261     uint16_t dummy3;
 262
 263     uint32_t fpip;
 264     uint32_t fpcs;
 265     uint32_t fpoo;
 266     uint32_t fpos;
 267     uint8_t fpregs1[8 * 10];
 268 };
 269
 270 struct fpxstate {
 271     uint16_t fpuc;
 272     uint16_t fpus;
 273     uint16_t fptag;
 274     uint16_t fop;
 275     uint32_t fpuip;
 276     uint16_t cs_sel;
 277     uint16_t dummy0;
 278     uint32_t fpudp;
 279     uint16_t ds_sel;
 280     uint16_t dummy1;
 281     uint32_t mxcsr;
 282     uint32_t mxcsr_mask;
 283     uint8_t fpregs1[8 * 16];
 284     uint8_t xmm_regs[16 * 16];
 285     uint8_t dummy2[96];
 286 };
 287
 288 static struct fpxstate fpx1 __attribute__((aligned(16)));
 289
 290 static void restore_native_fp_frstor(CPUState *env)
 291 {
 292     int fptag, i, j;
 293     struct fpstate fp1, *fp = &fp1;
 294
 295     fp->fpuc = env->fpuc;
 296     fp->fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
 297     fptag = 0;
 298     for (i=7; i>=0; i--) {
 299         fptag <<= 2;
 300         if (env->fptags[i]) {
 301             fptag |= 3;
 302         } else {
 303             /* the FPU automatically computes it */
 304         }
 305     }
 306     fp->fptag = fptag;
 307     j = env->fpstt;
 308     for(i = 0;i < 8; i++) {
 309         memcpy(&fp->fpregs1[i * 10], &env->fpregs[j].d, 10);
 310         j = (j + 1) & 7;
 311     }
 312     asm volatile ("frstor %0" : "=m" (*fp));
 313 }
 314
 315 static void save_native_fp_fsave(CPUState *env)
 316 {
 317     int fptag, i, j;
 318     uint16_t fpuc;
 319     struct fpstate fp1, *fp = &fp1;
 320
 321     asm volatile ("fsave %0" : : "m" (*fp));
 322     env->fpuc = fp->fpuc;
 323     env->fpstt = (fp->fpus >> 11) & 7;
 324     env->fpus = fp->fpus & ~0x3800;
 325     fptag = fp->fptag;
 326     for(i = 0;i < 8; i++) {
 327         env->fptags[i] = ((fptag & 3) == 3);
 328         fptag >>= 2;
 329     }
 330     j = env->fpstt;
 331     for(i = 0;i < 8; i++) {
 332         memcpy(&env->fpregs[j].d, &fp->fpregs1[i * 10], 10);
 333         j = (j + 1) & 7;
 334     }
 335     /* we must restore the default rounding state */
 336     fpuc = 0x037f | (env->fpuc & (3 << 10));
 337     asm volatile("fldcw %0" : : "m" (fpuc));
 338 }
 339
 340 static void restore_native_fp_fxrstor(CPUState *env)
 341 {
 342     struct fpxstate *fp = &fpx1;
 343     int i, j, fptag;
 344
 345     fp->fpuc = env->fpuc;
 346     fp->fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
 347     fptag = 0;
 348     for(i = 0; i < 8; i++)
 349         fptag |= (env->fptags[i] << i);
 350     fp->fptag = fptag ^ 0xff;
 351
 352     j = env->fpstt;
 353     for(i = 0;i < 8; i++) {
 354         memcpy(&fp->fpregs1[i * 16], &env->fpregs[j].d, 10);
 355         j = (j + 1) & 7;
 356     }
 357     if (env->cpuid_features & CPUID_SSE) {
 358         fp->mxcsr = env->mxcsr;
 359         /* XXX: check if DAZ is not available */
 360         fp->mxcsr_mask = 0xffff;
 361         memcpy(fp->xmm_regs, env->xmm_regs, CPU_NB_REGS * 16);
 362     }
 363     asm volatile ("fxrstor %0" : "=m" (*fp));
 364 }
 365
 366 static void save_native_fp_fxsave(CPUState *env)
 367 {
 368     struct fpxstate *fp = &fpx1;
 369     int fptag, i, j;
 370     uint16_t fpuc;
 371
 372     asm volatile ("fxsave %0" : : "m" (*fp));
 373     env->fpuc = fp->fpuc;
 374     env->fpstt = (fp->fpus >> 11) & 7;
 375     env->fpus = fp->fpus & ~0x3800;
 376     fptag = fp->fptag ^ 0xff;
 377     for(i = 0;i < 8; i++) {
 378         env->fptags[i] = (fptag >> i) & 1;
 379     }
 380     j = env->fpstt;
 381     for(i = 0;i < 8; i++) {
 382         memcpy(&env->fpregs[j].d, &fp->fpregs1[i * 16], 10);
 383         j = (j + 1) & 7;
 384     }
 385     if (env->cpuid_features & CPUID_SSE) {
 386         env->mxcsr = fp->mxcsr;
 387         memcpy(env->xmm_regs, fp->xmm_regs, CPU_NB_REGS * 16);
 388     }
 389
 390     /* we must restore the default rounding state */
 391     asm volatile ("fninit");
 392     fpuc = 0x037f | (env->fpuc & (3 << 10));
 393     asm volatile("fldcw %0" : : "m" (fpuc));
 394 }
 395
 396 static int do_syscall(CPUState *env,
 397                       struct kqemu_cpu_state *kenv)
 398 {
 399     int selector;
 400
 401     selector = (env->star >> 32) & 0xffff;
 402 #ifdef __x86_64__
 403     if (env->hflags & HF_LMA_MASK) {
 404         env->regs[R_ECX] = kenv->next_eip;
 405         env->regs[11] = env->eflags;
 406
 407         cpu_x86_set_cpl(env, 0);
 408         cpu_x86_load_seg_cache(env, R_CS, selector & 0xfffc,
 409                                0, 0xffffffff,
 410                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
 411                                DESC_S_MASK |
 412                                DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK | DESC_L_MASK);
 413         cpu_x86_load_seg_cache(env, R_SS, (selector + 8) & 0xfffc,
 414                                0, 0xffffffff,
 415                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
 416                                DESC_S_MASK |
 417                                DESC_W_MASK | DESC_A_MASK);
 418         env->eflags &= ~env->fmask;
 419         if (env->hflags & HF_CS64_MASK)
 420             env->eip = env->lstar;
 421         else
 422             env->eip = env->cstar;
 423     } else
 424 #endif
 425     {
 426         env->regs[R_ECX] = (uint32_t)kenv->next_eip;
 427
 428         cpu_x86_set_cpl(env, 0);
 429         cpu_x86_load_seg_cache(env, R_CS, selector & 0xfffc,
 430                            0, 0xffffffff,
 431                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
 432                                DESC_S_MASK |
 433                                DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK);
 434         cpu_x86_load_seg_cache(env, R_SS, (selector + 8) & 0xfffc,
 435                                0, 0xffffffff,
 436                                DESC_G_MASK | DESC_B_MASK | DESC_P_MASK |
 437                                DESC_S_MASK |
 438                                DESC_W_MASK | DESC_A_MASK);
 439         env->eflags &= ~(IF_MASK | RF_MASK | VM_MASK);
 440         env->eip = (uint32_t)env->star;
 441     }
 442     return 2;
 443 }
 444
 445 #ifdef PROFILE
 446
 447 #define PC_REC_SIZE 1
 448 #define PC_REC_HASH_BITS 16
 449 #define PC_REC_HASH_SIZE (1 << PC_REC_HASH_BITS)
 450
 451 typedef struct PCRecord {
 452     unsigned long pc;
 453     int64_t count;
 454     struct PCRecord *next;
 455 } PCRecord;
 456
 457 PCRecord *pc_rec_hash[PC_REC_HASH_SIZE];
 458 int nb_pc_records;
 459
 460 void kqemu_record_pc(unsigned long pc)
 461 {
 462     unsigned long h;
 463     PCRecord **pr, *r;
 464
 465     h = pc / PC_REC_SIZE;
 466     h = h ^ (h >> PC_REC_HASH_BITS);
 467     h &= (PC_REC_HASH_SIZE - 1);
 468     pr = &pc_rec_hash[h];
 469     for(;;) {
 470         r = *pr;
 471         if (r == NULL)
 472             break;
 473         if (r->pc == pc) {
 474             r->count++;
 475             return;
 476         }
 477         pr = &r->next;
 478     }
 479     r = malloc(sizeof(PCRecord));
 480     r->count = 1;
 481     r->pc = pc;
 482     r->next = NULL;
 483     *pr = r;
 484     nb_pc_records++;
 485 }
 486
 487 int pc_rec_cmp(const void *p1, const void *p2)
 488 {
 489     PCRecord *r1 = *(PCRecord **)p1;
 490     PCRecord *r2 = *(PCRecord **)p2;
 491     if (r1->count < r2->count)
 492         return 1;
 493     else if (r1->count == r2->count)
 494         return 0;
 495     else
 496         return -1;
 497 }
 498
 499 void kqemu_record_dump(void)
 500 {
 501     PCRecord **pr, *r;
 502     int i, h;
 503     FILE *f;
 504     int64_t total, sum;
 505
 506     pr = malloc(sizeof(PCRecord *) * nb_pc_records);
 507     i = 0;
 508     total = 0;
 509     for(h = 0; h < PC_REC_HASH_SIZE; h++) {
 510         for(r = pc_rec_hash[h]; r != NULL; r = r->next) {
 511             pr[i++] = r;
 512             total += r->count;
 513         }
 514     }
 515     qsort(pr, nb_pc_records, sizeof(PCRecord *), pc_rec_cmp);
 516
 517     f = fopen("/tmp/kqemu.stats", "w");
 518     if (!f) {
 519         perror("/tmp/kqemu.stats");
 520         exit(1);
 521     }
 522     fprintf(f, "total: %lld\n", total);
 523     sum = 0;
 524     for(i = 0; i < nb_pc_records; i++) {
 525         r = pr[i];
 526         sum += r->count;
 527         fprintf(f, "%08lx: %lld %0.2f%% %0.2f%%\n",
 528                 r->pc,
 529                 r->count,
 530                 (double)r->count / (double)total * 100.0,
 531                 (double)sum / (double)total * 100.0);
 532     }
 533     fclose(f);
 534     free(pr);
 535 }
 536 #else
 537 void kqemu_record_dump(void)
 538 {
 539 }
 540 #endif
 541
 542 int kqemu_cpu_exec(CPUState *env)
 543 {
 544     struct kqemu_cpu_state kcpu_state, *kenv = &kcpu_state;
 545     int ret;
 546 #ifdef _WIN32
 547     DWORD temp;
 548 #endif
 549
 550 #ifdef DEBUG
 551     if (loglevel & CPU_LOG_INT) {
 552         fprintf(logfile, "kqemu: cpu_exec: enter\n");
 553         cpu_dump_state(env, logfile, fprintf, 0);
 554     }
 555 #endif
 556     memcpy(kenv->regs, env->regs, sizeof(kenv->regs));
 557     kenv->eip = env->eip;
 558     kenv->eflags = env->eflags;
 559     memcpy(&kenv->segs, &env->segs, sizeof(env->segs));
 560     memcpy(&kenv->ldt, &env->ldt, sizeof(env->ldt));
 561     memcpy(&kenv->tr, &env->tr, sizeof(env->tr));
 562     memcpy(&kenv->gdt, &env->gdt, sizeof(env->gdt));
 563     memcpy(&kenv->idt, &env->idt, sizeof(env->idt));
 564     kenv->cr0 = env->cr[0];
 565     kenv->cr2 = env->cr[2];
 566     kenv->cr3 = env->cr[3];
 567     kenv->cr4 = env->cr[4];
 568     kenv->a20_mask = env->a20_mask;
 569 #if KQEMU_VERSION >= 0x010100
 570     kenv->efer = env->efer;
 571 #endif
 572     if (env->dr[7] & 0xff) {
 573         kenv->dr7 = env->dr[7];
 574         kenv->dr0 = env->dr[0];
 575         kenv->dr1 = env->dr[1];
 576         kenv->dr2 = env->dr[2];
 577         kenv->dr3 = env->dr[3];
 578     } else {
 579         kenv->dr7 = 0;
 580     }
 581     kenv->dr6 = env->dr[6];
 582     kenv->cpl = 3;
 583     kenv->nb_pages_to_flush = nb_pages_to_flush;
 584     nb_pages_to_flush = 0;
 585 #if KQEMU_VERSION >= 0x010200
 586     kenv->user_only = 1;
 587     kenv->nb_ram_pages_to_update = nb_ram_pages_to_update;
 588 #endif
 589     nb_ram_pages_to_update = 0;
 590
 591     if (!(kenv->cr0 & CR0_TS_MASK)) {
 592         if (env->cpuid_features & CPUID_FXSR)
 593             restore_native_fp_fxrstor(env);
 594         else
 595             restore_native_fp_frstor(env);
 596     }
 597
 598 #ifdef _WIN32
 599     DeviceIoControl(kqemu_fd, KQEMU_EXEC,
 600                     kenv, sizeof(struct kqemu_cpu_state),
 601                     kenv, sizeof(struct kqemu_cpu_state),
 602                     &temp, NULL);
 603     ret = kenv->retval;
 604 #else
 605 #if KQEMU_VERSION >= 0x010100
 606     ioctl(kqemu_fd, KQEMU_EXEC, kenv);
 607     ret = kenv->retval;
 608 #else
 609     ret = ioctl(kqemu_fd, KQEMU_EXEC, kenv);
 610 #endif
 611 #endif
 612     if (!(kenv->cr0 & CR0_TS_MASK)) {
 613         if (env->cpuid_features & CPUID_FXSR)
 614             save_native_fp_fxsave(env);
 615         else
 616             save_native_fp_fsave(env);
 617     }
 618
 619     memcpy(env->regs, kenv->regs, sizeof(env->regs));
 620     env->eip = kenv->eip;
 621     env->eflags = kenv->eflags;
 622     memcpy(env->segs, kenv->segs, sizeof(env->segs));
 623 #if 0
 624     /* no need to restore that */
 625     memcpy(env->ldt, kenv->ldt, sizeof(env->ldt));
 626     memcpy(env->tr, kenv->tr, sizeof(env->tr));
 627     memcpy(env->gdt, kenv->gdt, sizeof(env->gdt));
 628     memcpy(env->idt, kenv->idt, sizeof(env->idt));
 629     env->cr[0] = kenv->cr0;
 630     env->cr[3] = kenv->cr3;
 631     env->cr[4] = kenv->cr4;
 632     env->a20_mask = kenv->a20_mask;
 633 #endif
 634     env->cr[2] = kenv->cr2;
 635     env->dr[6] = kenv->dr6;
 636
 637 #if KQEMU_VERSION >= 0x010200
 638     if (kenv->nb_ram_pages_to_update > 0) {
 639         cpu_tlb_update_dirty(env);
 640     }
 641 #endif
 642
 643     /* restore the hidden flags */
 644     {
 645         unsigned int new_hflags;
 646 #ifdef TARGET_X86_64
 647         if ((env->hflags & HF_LMA_MASK) &&
 648             (env->segs[R_CS].flags & DESC_L_MASK)) {
 649             /* long mode */
 650             new_hflags = HF_CS32_MASK | HF_SS32_MASK | HF_CS64_MASK;
 651         } else
 652 #endif
 653         {
 654             /* legacy / compatibility case */
 655             new_hflags = (env->segs[R_CS].flags & DESC_B_MASK)
 656                 >> (DESC_B_SHIFT - HF_CS32_SHIFT);
 657             new_hflags |= (env->segs[R_SS].flags & DESC_B_MASK)
 658                 >> (DESC_B_SHIFT - HF_SS32_SHIFT);
 659             if (!(env->cr[0] & CR0_PE_MASK) ||
 660                    (env->eflags & VM_MASK) ||
 661                    !(env->hflags & HF_CS32_MASK)) {
 662                 /* XXX: try to avoid this test. The problem comes from the
 663                    fact that is real mode or vm86 mode we only modify the
 664                    'base' and 'selector' fields of the segment cache to go
 665                    faster. A solution may be to force addseg to one in
 666                    translate-i386.c. */
 667                 new_hflags |= HF_ADDSEG_MASK;
 668             } else {
 669                 new_hflags |= ((env->segs[R_DS].base |
 670                                 env->segs[R_ES].base |
 671                                 env->segs[R_SS].base) != 0) <<
 672                     HF_ADDSEG_SHIFT;
 673             }
 674         }
 675         env->hflags = (env->hflags &
 676            ~(HF_CS32_MASK | HF_SS32_MASK | HF_CS64_MASK | HF_ADDSEG_MASK)) |
 677             new_hflags;
 678     }
 679
 680 #ifdef DEBUG
 681     if (loglevel & CPU_LOG_INT) {
 682         fprintf(logfile, "kqemu: kqemu_cpu_exec: ret=0x%x\n", ret);
 683     }
 684 #endif
 685     if (ret == KQEMU_RET_SYSCALL) {
 686         /* syscall instruction */
 687         return do_syscall(env, kenv);
 688     } else
 689     if ((ret & 0xff00) == KQEMU_RET_INT) {
 690         env->exception_index = ret & 0xff;
 691         env->error_code = 0;
 692         env->exception_is_int = 1;
 693         env->exception_next_eip = kenv->next_eip;
 694 #ifdef DEBUG
 695         if (loglevel & CPU_LOG_INT) {
 696             fprintf(logfile, "kqemu: interrupt v=%02x:\n",
 697                     env->exception_index);
 698             cpu_dump_state(env, logfile, fprintf, 0);
 699         }
 700 #endif
 701         return 1;
 702     } else if ((ret & 0xff00) == KQEMU_RET_EXCEPTION) {
 703         env->exception_index = ret & 0xff;
 704         env->error_code = kenv->error_code;
 705         env->exception_is_int = 0;
 706         env->exception_next_eip = 0;
 707 #ifdef DEBUG
 708         if (loglevel & CPU_LOG_INT) {
 709             fprintf(logfile, "kqemu: exception v=%02x e=%04x:\n",
 710                     env->exception_index, env->error_code);
 711             cpu_dump_state(env, logfile, fprintf, 0);
 712         }
 713 #endif
 714         return 1;
 715     } else if (ret == KQEMU_RET_INTR) {
 716 #ifdef DEBUG
 717         if (loglevel & CPU_LOG_INT) {
 718             cpu_dump_state(env, logfile, fprintf, 0);
 719         }
 720 #endif
 721         return 0;
 722     } else if (ret == KQEMU_RET_SOFTMMU) {
 723 #ifdef PROFILE
 724         kqemu_record_pc(env->eip + env->segs[R_CS].base);
 725 #endif
 726 #ifdef DEBUG
 727         if (loglevel & CPU_LOG_INT) {
 728             cpu_dump_state(env, logfile, fprintf, 0);
 729         }
 730 #endif
 731         return 2;
 732     } else {
 733         cpu_dump_state(env, stderr, fprintf, 0);
 734         fprintf(stderr, "Unsupported return value: 0x%x\n", ret);
 735         exit(1);
 736     }
 737     return 0;
 738 }
 739
 740 #endif