ntoskrnl/include/internal/i386/ke.h

   1 #pragma once
   2
   3 #ifndef __ASM__
   4
   5 #include "intrin_i.h"
   6
   7 //
   8 // Thread Dispatcher Header DebugActive Mask
   9 //
  10 #define DR_MASK(x)                              (1 << (x))
  11 #define DR_REG_MASK                             0x4F
  12
  13 //
  14 // INT3 is 1 byte long
  15 //
  16 #define KD_BREAKPOINT_TYPE        UCHAR
  17 #define KD_BREAKPOINT_SIZE        sizeof(UCHAR)
  18 #define KD_BREAKPOINT_VALUE       0xCC
  19
  20 //
  21 // Macros for getting and setting special purpose registers in portable code
  22 //
  23 #define KeGetContextPc(Context) \
  24     ((Context)->Eip)
  25
  26 #define KeSetContextPc(Context, ProgramCounter) \
  27     ((Context)->Eip = (ProgramCounter))
  28
  29 #define KeGetTrapFramePc(TrapFrame) \
  30     ((TrapFrame)->Eip)
  31
  32 #define KiGetLinkedTrapFrame(x) \
  33     (PKTRAP_FRAME)((x)->Edx)
  34
  35 #define KeGetContextReturnRegister(Context) \
  36     ((Context)->Eax)
  37
  38 #define KeSetContextReturnRegister(Context, ReturnValue) \
  39     ((Context)->Eax = (ReturnValue))
  40
  41 //
  42 // Macro to get trap and exception frame from a thread stack
  43 //
  44 #define KeGetTrapFrame(Thread) \
  45     (PKTRAP_FRAME)((ULONG_PTR)((Thread)->InitialStack) - \
  46                    sizeof(KTRAP_FRAME) - \
  47                    sizeof(FX_SAVE_AREA))
  48
  49 #define KeGetExceptionFrame(Thread) \
  50     NULL
  51
  52 //
  53 // Macro to get context switches from the PRCB
  54 // All architectures but x86 have it in the PRCB's KeContextSwitches
  55 //
  56 #define KeGetContextSwitches(Prcb)  \
  57     CONTAINING_RECORD(Prcb, KIPCR, PrcbData)->ContextSwitches
  58
  59 //
  60 // Macro to get the second level cache size field name which differs between
  61 // CISC and RISC architectures, as the former has unified I/D cache
  62 //
  63 #define KiGetSecondLevelDCacheSize() ((PKIPCR)KeGetPcr())->SecondLevelCacheSize
  64
  65 //
  66 // Returns the Interrupt State from a Trap Frame.
  67 // ON = TRUE, OFF = FALSE
  68 //
  69 #define KeGetTrapFrameInterruptState(TrapFrame) \
  70         BooleanFlagOn((TrapFrame)->EFlags, EFLAGS_INTERRUPT_MASK)
  71
  72 //
  73 // Flags for exiting a trap
  74 //
  75 #define KTE_SKIP_PM_BIT  (((KTRAP_EXIT_SKIP_BITS) { { .SkipPreviousMode = TRUE } }).Bits)
  76 #define KTE_SKIP_SEG_BIT (((KTRAP_EXIT_SKIP_BITS) { { .SkipSegments  = TRUE } }).Bits)
  77 #define KTE_SKIP_VOL_BIT (((KTRAP_EXIT_SKIP_BITS) { { .SkipVolatiles = TRUE } }).Bits)
  78
  79 typedef union _KTRAP_EXIT_SKIP_BITS
  80 {
  81     struct
  82     {
  83         UCHAR SkipPreviousMode:1;
  84         UCHAR SkipSegments:1;
  85         UCHAR SkipVolatiles:1;
  86         UCHAR Reserved:5;
  87     };
  88     UCHAR Bits;
  89 } KTRAP_EXIT_SKIP_BITS, *PKTRAP_EXIT_SKIP_BITS;
  90
  91
  92 //
  93 // Flags used by the VDM/V8086 emulation engine for determining instruction prefixes
  94 //
  95 #define PFX_FLAG_ES                0x00000100
  96 #define PFX_FLAG_CS                0x00000200
  97 #define PFX_FLAG_SS                0x00000400
  98 #define PFX_FLAG_DS                0x00000800
  99 #define PFX_FLAG_FS                0x00001000
 100 #define PFX_FLAG_GS                0x00002000
 101 #define PFX_FLAG_OPER32            0x00004000
 102 #define PFX_FLAG_ADDR32            0x00008000
 103 #define PFX_FLAG_LOCK              0x00010000
 104 #define PFX_FLAG_REPNE             0x00020000
 105 #define PFX_FLAG_REP               0x00040000
 106
 107 //
 108 // VDM Helper Macros
 109 //
 110 // All VDM/V8086 opcode emulators have the same FASTCALL function definition.
 111 // We need to keep 2 parameters while the original ASM implementation uses 4:
 112 // TrapFrame, PrefixFlags, Eip, InstructionSize;
 113 //
 114 // We pass the trap frame, and prefix flags, in our two parameters.
 115 //
 116 // We then realize that since the smallest prefix flag is 0x100, this gives us
 117 // a count of up to 0xFF. So we OR in the instruction size with the prefix flags
 118 //
 119 // We further realize that we always have access to EIP from the trap frame, and
 120 // that if we want the *current instruction* EIP, we simply have to add the
 121 // instruction size *MINUS ONE*, and that gives us the EIP we should be looking
 122 // at now, so we don't need to use the stack to push this parameter.
 123 //
 124 // We actually only care about the *current instruction* EIP in one location,
 125 // so although it may be slightly more expensive to re-calculate the EIP one
 126 // more time, this way we don't redefine ALL opcode handlers to have 3 parameters,
 127 // which would be forcing stack usage in all other scenarios.
 128 //
 129 #define KiVdmSetVdmEFlags(x)        InterlockedOr((PLONG)KiNtVdmState, (x));
 130 #define KiVdmClearVdmEFlags(x)      InterlockedAnd((PLONG)KiNtVdmState, ~(x))
 131 #define KiCallVdmHandler(x)         KiVdmOpcode##x(TrapFrame, Flags)
 132 #define KiCallVdmPrefixHandler(x)   KiVdmOpcodePrefix(TrapFrame, Flags | x)
 133 #define KiVdmUnhandledOpcode(x)                     \
 134     BOOLEAN                                         \
 135     FASTCALL                                        \
 136     KiVdmOpcode##x(IN PKTRAP_FRAME TrapFrame,       \
 137                    IN ULONG Flags)                  \
 138     {                                               \
 139         /* Not yet handled */                       \
 140         UNIMPLEMENTED_DBGBREAK();                   \
 141         return FALSE;                               \
 142     }
 143
 144 C_ASSERT(NPX_FRAME_LENGTH == sizeof(FX_SAVE_AREA));
 145
 146 //
 147 // Local parameters
 148 //
 149 typedef struct _KV86_FRAME
 150 {
 151     PVOID ThreadStack;
 152     PVOID ThreadTeb;
 153     PVOID PcrTeb;
 154 } KV86_FRAME, *PKV86_FRAME;
 155
 156 //
 157 // Virtual Stack Frame
 158 //
 159 typedef struct _KV8086_STACK_FRAME
 160 {
 161     KTRAP_FRAME TrapFrame;
 162     FX_SAVE_AREA NpxArea;
 163     KV86_FRAME V86Frame;
 164 } KV8086_STACK_FRAME, *PKV8086_STACK_FRAME;
 165
 166 //
 167 // Large Pages Support
 168 //
 169 typedef struct _LARGE_IDENTITY_MAP
 170 {
 171     PHARDWARE_PTE TopLevelDirectory;
 172     ULONG Cr3;
 173     ULONG_PTR StartAddress;
 174     ULONG PagesCount;
 175     PVOID PagesList[30];
 176 } LARGE_IDENTITY_MAP, *PLARGE_IDENTITY_MAP;
 177
 178 /* Diable interrupts and return whether they were enabled before */
 179 FORCEINLINE
 180 BOOLEAN
 181 KeDisableInterrupts(VOID)
 182 {
 183     ULONG Flags;
 184     BOOLEAN Return;
 185
 186     /* Get EFLAGS and check if the interrupt bit is set */
 187     Flags = __readeflags();
 188     Return = (Flags & EFLAGS_INTERRUPT_MASK) ? TRUE: FALSE;
 189
 190     /* Disable interrupts */
 191     _disable();
 192     return Return;
 193 }
 194
 195 /* Restore previous interrupt state */
 196 FORCEINLINE
 197 VOID
 198 KeRestoreInterrupts(BOOLEAN WereEnabled)
 199 {
 200     if (WereEnabled) _enable();
 201 }
 202
 203 //
 204 // Registers an interrupt handler with an IDT vector
 205 //
 206 FORCEINLINE
 207 VOID
 208 KeRegisterInterruptHandler(IN ULONG Vector,
 209                            IN PVOID Handler)
 210 {
 211     UCHAR Entry;
 212     ULONG_PTR Address;
 213     PKIPCR Pcr = (PKIPCR)KeGetPcr();
 214
 215     //
 216     // Get the entry from the HAL
 217     //
 218     Entry = HalVectorToIDTEntry(Vector);
 219     Address = PtrToUlong(Handler);
 220
 221     //
 222     // Now set the data
 223     //
 224     Pcr->IDT[Entry].ExtendedOffset = (USHORT)(Address >> 16);
 225     Pcr->IDT[Entry].Offset = (USHORT)Address;
 226 }
 227
 228 //
 229 // Returns the registered interrupt handler for a given IDT vector
 230 //
 231 FORCEINLINE
 232 PVOID
 233 KeQueryInterruptHandler(IN ULONG Vector)
 234 {
 235     PKIPCR Pcr = (PKIPCR)KeGetPcr();
 236     UCHAR Entry;
 237
 238     //
 239     // Get the entry from the HAL
 240     //
 241     Entry = HalVectorToIDTEntry(Vector);
 242
 243     //
 244     // Read the entry from the IDT
 245     //
 246     return (PVOID)(((Pcr->IDT[Entry].ExtendedOffset << 16) & 0xFFFF0000) |
 247                     (Pcr->IDT[Entry].Offset & 0xFFFF));
 248 }
 249
 250 //
 251 // Invalidates the TLB entry for a specified address
 252 //
 253 FORCEINLINE
 254 VOID
 255 KeInvalidateTlbEntry(IN PVOID Address)
 256 {
 257     /* Invalidate the TLB entry for this address */
 258     __invlpg(Address);
 259 }
 260
 261 FORCEINLINE
 262 VOID
 263 KeFlushProcessTb(VOID)
 264 {
 265     /* Flush the TLB by resetting CR3 */
 266     __writecr3(__readcr3());
 267 }
 268
 269 FORCEINLINE
 270 VOID
 271 KeSweepICache(IN PVOID BaseAddress,
 272               IN SIZE_T FlushSize)
 273 {
 274     //
 275     // Always sweep the whole cache
 276     //
 277     UNREFERENCED_PARAMETER(BaseAddress);
 278     UNREFERENCED_PARAMETER(FlushSize);
 279     __wbinvd();
 280 }
 281
 282 FORCEINLINE
 283 PRKTHREAD
 284 KeGetCurrentThread(VOID)
 285 {
 286     /* Return the current thread */
 287     return ((PKIPCR)KeGetPcr())->PrcbData.CurrentThread;
 288 }
 289
 290 FORCEINLINE
 291 VOID
 292 KiRundownThread(IN PKTHREAD Thread)
 293 {
 294 #ifndef CONFIG_SMP
 295     /* Check if this is the NPX Thread */
 296     if (KeGetCurrentPrcb()->NpxThread == Thread)
 297     {
 298         /* Clear it */
 299         KeGetCurrentPrcb()->NpxThread = NULL;
 300         Ke386FnInit();
 301     }
 302 #else
 303     /* Nothing to do */
 304 #endif
 305 }
 306
 307 FORCEINLINE
 308 VOID
 309 Ke386SetGdtEntryBase(PKGDTENTRY GdtEntry, PVOID BaseAddress)
 310 {
 311     GdtEntry->BaseLow = (USHORT)((ULONG_PTR)BaseAddress & 0xFFFF);
 312     GdtEntry->HighWord.Bytes.BaseMid = (UCHAR)((ULONG_PTR)BaseAddress >> 16);
 313     GdtEntry->HighWord.Bytes.BaseHi = (UCHAR)((ULONG_PTR)BaseAddress >> 24);
 314 }
 315
 316 FORCEINLINE
 317 VOID
 318 KiSetTebBase(PKPCR Pcr, PVOID TebAddress)
 319 {
 320     Pcr->NtTib.Self = TebAddress;
 321     Ke386SetGdtEntryBase(&Pcr->GDT[KGDT_R3_TEB / sizeof(KGDTENTRY)], TebAddress);
 322 }
 323
 324 VOID
 325 FASTCALL
 326 Ki386InitializeTss(
 327     IN PKTSS Tss,
 328     IN PKIDTENTRY Idt,
 329     IN PKGDTENTRY Gdt
 330 );
 331
 332 VOID
 333 NTAPI
 334 KiSetCR0Bits(VOID);
 335
 336 VOID
 337 NTAPI
 338 KiGetCacheInformation(VOID);
 339
 340 BOOLEAN
 341 NTAPI
 342 KiIsNpxPresent(
 343     VOID
 344 );
 345
 346 BOOLEAN
 347 NTAPI
 348 KiIsNpxErrataPresent(
 349     VOID
 350 );
 351
 352 VOID
 353 NTAPI
 354 KiSetProcessorType(VOID);
 355
 356 ULONG
 357 NTAPI
 358 KiGetFeatureBits(VOID);
 359
 360 VOID
 361 NTAPI
 362 KiThreadStartup(VOID);
 363
 364 NTSTATUS
 365 NTAPI
 366 Ke386GetGdtEntryThread(
 367     IN PKTHREAD Thread,
 368     IN ULONG Offset,
 369     IN PKGDTENTRY Descriptor
 370 );
 371
 372 VOID
 373 NTAPI
 374 KiFlushNPXState(
 375     IN FLOATING_SAVE_AREA *SaveArea
 376 );
 377
 378 VOID
 379 NTAPI
 380 Ki386AdjustEsp0(
 381     IN PKTRAP_FRAME TrapFrame
 382 );
 383
 384 VOID
 385 NTAPI
 386 Ki386SetupAndExitToV86Mode(
 387     OUT PTEB VdmTeb
 388 );
 389
 390 VOID
 391 NTAPI
 392 KeI386VdmInitialize(
 393     VOID
 394 );
 395
 396 ULONG_PTR
 397 NTAPI
 398 Ki386EnableGlobalPage(
 399     IN ULONG_PTR Context
 400 );
 401
 402 ULONG_PTR
 403 NTAPI
 404 Ki386EnableTargetLargePage(
 405     IN ULONG_PTR Context
 406 );
 407
 408 BOOLEAN
 409 NTAPI
 410 Ki386CreateIdentityMap(
 411     IN PLARGE_IDENTITY_MAP IdentityMap,
 412     IN PVOID StartPtr,
 413     IN ULONG Length
 414 );
 415
 416 VOID
 417 NTAPI
 418 Ki386FreeIdentityMap(
 419     IN PLARGE_IDENTITY_MAP IdentityMap
 420 );
 421
 422 VOID
 423 NTAPI
 424 Ki386EnableCurrentLargePage(
 425     IN ULONG_PTR StartAddress,
 426     IN ULONG Cr3
 427 );
 428
 429 VOID
 430 NTAPI
 431 KiI386PentiumLockErrataFixup(
 432     VOID
 433 );
 434
 435 VOID
 436 NTAPI
 437 KiInitializePAT(
 438     VOID
 439 );
 440
 441 VOID
 442 NTAPI
 443 KiInitializeMTRR(
 444     IN BOOLEAN FinalCpu
 445 );
 446
 447 VOID
 448 NTAPI
 449 KiAmdK6InitializeMTRR(
 450     VOID
 451 );
 452
 453 VOID
 454 NTAPI
 455 KiRestoreFastSyscallReturnState(
 456     VOID
 457 );
 458
 459 ULONG_PTR
 460 NTAPI
 461 Ki386EnableDE(
 462     IN ULONG_PTR Context
 463 );
 464
 465 ULONG_PTR
 466 NTAPI
 467 Ki386EnableFxsr(
 468     IN ULONG_PTR Context
 469 );
 470
 471 ULONG_PTR
 472 NTAPI
 473 Ki386EnableXMMIExceptions(
 474     IN ULONG_PTR Context
 475 );
 476
 477 BOOLEAN
 478 NTAPI
 479 VdmDispatchBop(
 480     IN PKTRAP_FRAME TrapFrame
 481 );
 482
 483 BOOLEAN
 484 FASTCALL
 485 KiVdmOpcodePrefix(
 486     IN PKTRAP_FRAME TrapFrame,
 487     IN ULONG Flags
 488 );
 489
 490 BOOLEAN
 491 FASTCALL
 492 Ki386HandleOpcodeV86(
 493     IN PKTRAP_FRAME TrapFrame
 494 );
 495
 496 DECLSPEC_NORETURN
 497 VOID
 498 FASTCALL
 499 KiEoiHelper(
 500     IN PKTRAP_FRAME TrapFrame
 501 );
 502
 503 VOID
 504 FASTCALL
 505 Ki386BiosCallReturnAddress(
 506     IN PKTRAP_FRAME TrapFrame
 507 );
 508
 509 ULONG_PTR
 510 FASTCALL
 511 KiExitV86Mode(
 512     IN PKTRAP_FRAME TrapFrame
 513 );
 514
 515 DECLSPEC_NORETURN
 516 VOID
 517 NTAPI
 518 KiDispatchExceptionFromTrapFrame(
 519     IN NTSTATUS Code,
 520     IN ULONG Flags,
 521     IN ULONG_PTR Address,
 522     IN ULONG ParameterCount,
 523     IN ULONG_PTR Parameter1,
 524     IN ULONG_PTR Parameter2,
 525     IN ULONG_PTR Parameter3,
 526     IN PKTRAP_FRAME TrapFrame
 527 );
 528
 529 NTSTATUS
 530 NTAPI
 531 KiConvertToGuiThread(
 532     VOID
 533 );
 534
 535 //
 536 // Global x86 only Kernel data
 537 //
 538 extern PVOID Ki386IopmSaveArea;
 539 extern ULONG KeI386EFlagsAndMaskV86;
 540 extern ULONG KeI386EFlagsOrMaskV86;
 541 extern BOOLEAN KeI386VirtualIntExtensions;
 542 extern KIDTENTRY KiIdt[MAXIMUM_IDTVECTOR+1];
 543 extern KDESCRIPTOR KiIdtDescriptor;
 544 extern BOOLEAN KiI386PentiumLockErrataPresent;
 545 extern ULONG KeI386NpxPresent;
 546 extern ULONG KeI386XMMIPresent;
 547 extern ULONG KeI386FxsrPresent;
 548 extern ULONG KiMXCsrMask;
 549 extern ULONG KeI386CpuType;
 550 extern ULONG KeI386CpuStep;
 551 extern ULONG KiFastSystemCallDisable;
 552 extern UCHAR KiDebugRegisterTrapOffsets[9];
 553 extern UCHAR KiDebugRegisterContextOffsets[9];
 554 extern DECLSPEC_NORETURN VOID __cdecl KiTrap02(VOID);
 555 extern VOID __cdecl KiTrap08(VOID);
 556 extern VOID __cdecl KiTrap13(VOID);
 557 extern VOID __cdecl KiFastCallEntry(VOID);
 558 extern VOID NTAPI ExpInterlockedPopEntrySListFault(VOID);
 559 extern VOID NTAPI ExpInterlockedPopEntrySListResume(VOID);
 560 extern VOID __cdecl CopyParams(VOID);
 561 extern VOID __cdecl ReadBatch(VOID);
 562 extern CHAR KiSystemCallExitBranch[];
 563 extern CHAR KiSystemCallExit[];
 564 extern CHAR KiSystemCallExit2[];
 565
 566 //
 567 // Trap Macros
 568 //
 569 #include "trap_x.h"
 570
 571 //
 572 // Returns a thread's FPU save area
 573 //
 574 FORCEINLINE
 575 PFX_SAVE_AREA
 576 KiGetThreadNpxArea(IN PKTHREAD Thread)
 577 {
 578     ASSERT((ULONG_PTR)Thread->InitialStack % 16 == 0);
 579     return (PFX_SAVE_AREA)((ULONG_PTR)Thread->InitialStack - sizeof(FX_SAVE_AREA));
 580 }
 581
 582 //
 583 // Sanitizes a selector
 584 //
 585 FORCEINLINE
 586 ULONG
 587 Ke386SanitizeSeg(IN ULONG Cs,
 588                 IN KPROCESSOR_MODE Mode)
 589 {
 590     //
 591     // Check if we're in kernel-mode, and force CPL 0 if so.
 592     // Otherwise, force CPL 3.
 593     //
 594     return ((Mode == KernelMode) ?
 595             (Cs & (0xFFFF & ~RPL_MASK)) :
 596             (RPL_MASK | (Cs & 0xFFFF)));
 597 }
 598
 599 //
 600 // Sanitizes EFLAGS
 601 //
 602 FORCEINLINE
 603 ULONG
 604 Ke386SanitizeFlags(IN ULONG Eflags,
 605                    IN KPROCESSOR_MODE Mode)
 606 {
 607     //
 608     // Check if we're in kernel-mode, and sanitize EFLAGS if so.
 609     // Otherwise, also force interrupt mask on.
 610     //
 611     return ((Mode == KernelMode) ?
 612             (Eflags & (EFLAGS_USER_SANITIZE | EFLAGS_INTERRUPT_MASK)) :
 613             (EFLAGS_INTERRUPT_MASK | (Eflags & EFLAGS_USER_SANITIZE)));
 614 }
 615
 616 //
 617 // Sanitizes a Debug Register
 618 //
 619 FORCEINLINE
 620 PVOID
 621 Ke386SanitizeDr(IN PVOID DrAddress,
 622                 IN KPROCESSOR_MODE Mode)
 623 {
 624     //
 625     // Check if we're in kernel-mode, and return the address directly if so.
 626     // Otherwise, make sure it's not inside the kernel-mode address space.
 627     // If it is, then clear the address.
 628     //
 629     return ((Mode == KernelMode) ? DrAddress :
 630             (DrAddress <= MM_HIGHEST_USER_ADDRESS) ? DrAddress : 0);
 631 }
 632
 633 //
 634 // Exception with no arguments
 635 //
 636 FORCEINLINE
 637 DECLSPEC_NORETURN
 638 VOID
 639 KiDispatchException0Args(IN NTSTATUS Code,
 640                          IN ULONG_PTR Address,
 641                          IN PKTRAP_FRAME TrapFrame)
 642 {
 643     /* Helper for exceptions with no arguments */
 644     KiDispatchExceptionFromTrapFrame(Code, 0, Address, 0, 0, 0, 0, TrapFrame);
 645 }
 646
 647 //
 648 // Exception with one argument
 649 //
 650 FORCEINLINE
 651 DECLSPEC_NORETURN
 652 VOID
 653 KiDispatchException1Args(IN NTSTATUS Code,
 654                          IN ULONG_PTR Address,
 655                          IN ULONG P1,
 656                          IN PKTRAP_FRAME TrapFrame)
 657 {
 658     /* Helper for exceptions with no arguments */
 659     KiDispatchExceptionFromTrapFrame(Code, 0, Address, 1, P1, 0, 0, TrapFrame);
 660 }
 661
 662 //
 663 // Exception with two arguments
 664 //
 665 FORCEINLINE
 666 DECLSPEC_NORETURN
 667 VOID
 668 KiDispatchException2Args(IN NTSTATUS Code,
 669                          IN ULONG_PTR Address,
 670                          IN ULONG P1,
 671                          IN ULONG P2,
 672                          IN PKTRAP_FRAME TrapFrame)
 673 {
 674     /* Helper for exceptions with no arguments */
 675     KiDispatchExceptionFromTrapFrame(Code, 0, Address, 2, P1, P2, 0, TrapFrame);
 676 }
 677
 678 //
 679 // Performs a system call
 680 //
 681
 682     /*
 683      * This sequence does a RtlCopyMemory(Stack - StackBytes, Arguments, StackBytes)
 684      * and then calls the function associated with the system call.
 685      *
 686      * It's done in assembly for two reasons: we need to muck with the stack,
 687      * and the call itself restores the stack back for us. The only way to do
 688      * this in C is to do manual C handlers for every possible number of args on
 689      * the stack, and then have the handler issue a call by pointer. This is
 690      * wasteful since it'll basically push the values twice and require another
 691      * level of call indirection.
 692      *
 693      * The ARM kernel currently does this, but it should probably be changed
 694      * later to function like this as well.
 695      *
 696      */
 697 #ifdef __GNUC__
 698 FORCEINLINE
 699 NTSTATUS
 700 KiSystemCallTrampoline(IN PVOID Handler,
 701                        IN PVOID Arguments,
 702                        IN ULONG StackBytes)
 703 {
 704     NTSTATUS Result;
 705
 706     __asm__ __volatile__
 707     (
 708         "subl %1, %%esp\n\t"
 709         "movl %%esp, %%edi\n\t"
 710         "movl %2, %%esi\n\t"
 711         "shrl $2, %1\n\t"
 712         "rep movsd\n\t"
 713         "call *%3\n\t"
 714         "movl %%eax, %0"
 715         : "=r"(Result)
 716         : "c"(StackBytes),
 717           "d"(Arguments),
 718           "r"(Handler)
 719         : "%esp", "%esi", "%edi"
 720     );
 721     return Result;
 722 }
 723 #elif defined(_MSC_VER)
 724 FORCEINLINE
 725 NTSTATUS
 726 KiSystemCallTrampoline(IN PVOID Handler,
 727                        IN PVOID Arguments,
 728                        IN ULONG StackBytes)
 729 {
 730     __asm
 731     {
 732         mov ecx, StackBytes
 733         mov esi, Arguments
 734         mov eax, Handler
 735         sub esp, ecx
 736         mov edi, esp
 737         shr ecx, 2
 738         rep movsd
 739         call eax
 740     }
 741     /* Return with result in EAX */
 742 }
 743 #else
 744 #error Unknown Compiler
 745 #endif
 746
 747
 748 //
 749 // Checks for pending APCs
 750 //
 751 FORCEINLINE
 752 VOID
 753 KiCheckForApcDelivery(IN PKTRAP_FRAME TrapFrame)
 754 {
 755     PKTHREAD Thread;
 756     KIRQL OldIrql;
 757
 758     /* Check for V8086 or user-mode trap */
 759     if ((TrapFrame->EFlags & EFLAGS_V86_MASK) || (KiUserTrap(TrapFrame)))
 760     {
 761         /* Get the thread */
 762         Thread = KeGetCurrentThread();
 763         while (TRUE)
 764         {
 765             /* Turn off the alerted state for kernel mode */
 766             Thread->Alerted[KernelMode] = FALSE;
 767
 768             /* Are there pending user APCs? */
 769             if (!Thread->ApcState.UserApcPending) break;
 770
 771             /* Raise to APC level and enable interrupts */
 772             OldIrql = KfRaiseIrql(APC_LEVEL);
 773             _enable();
 774
 775             /* Deliver APCs */
 776             KiDeliverApc(UserMode, NULL, TrapFrame);
 777
 778             /* Restore IRQL and disable interrupts once again */
 779             KfLowerIrql(OldIrql);
 780             _disable();
 781         }
 782     }
 783 }
 784
 785 //
 786 // Switches from boot loader to initial kernel stack
 787 //
 788 FORCEINLINE
 789 VOID
 790 KiSwitchToBootStack(IN ULONG_PTR InitialStack)
 791 {
 792     VOID NTAPI KiSystemStartupBootStack(VOID);
 793
 794     /* We have to switch to a new stack before continuing kernel initialization */
 795 #ifdef __GNUC__
 796     __asm__
 797     (
 798         "movl %0, %%esp\n\t"
 799         "subl %1, %%esp\n\t"
 800         "pushl %2\n\t"
 801         "jmp _KiSystemStartupBootStack@0"
 802         :
 803         : "c"(InitialStack),
 804           "i"(NPX_FRAME_LENGTH + KTRAP_FRAME_ALIGN + KTRAP_FRAME_LENGTH),
 805           "i"(CR0_EM | CR0_TS | CR0_MP),
 806           "p"(KiSystemStartupBootStack)
 807         : "%esp"
 808     );
 809 #elif defined(_MSC_VER)
 810     __asm
 811     {
 812         mov esp, InitialStack
 813         sub esp, (NPX_FRAME_LENGTH + KTRAP_FRAME_ALIGN + KTRAP_FRAME_LENGTH)
 814         push (CR0_EM | CR0_TS | CR0_MP)
 815         jmp KiSystemStartupBootStack
 816     }
 817 #else
 818 #error Unknown Compiler
 819 #endif
 820 }
 821
 822 //
 823 // Emits the iret instruction for C code
 824 //
 825 FORCEINLINE
 826 DECLSPEC_NORETURN
 827 VOID
 828 KiIret(VOID)
 829 {
 830 #if defined(__GNUC__)
 831     __asm__ __volatile__
 832     (
 833         "iret"
 834     );
 835 #elif defined(_MSC_VER)
 836     __asm
 837     {
 838         iretd
 839     }
 840 #else
 841 #error Unsupported compiler
 842 #endif
 843     UNREACHABLE;
 844 }
 845
 846 //
 847 // Normally this is done by the HAL, but on x86 as an optimization, the kernel
 848 // initiates the end by calling back into the HAL and exiting the trap here.
 849 //
 850 FORCEINLINE
 851 VOID
 852 KiEndInterrupt(IN KIRQL Irql,
 853                IN PKTRAP_FRAME TrapFrame)
 854 {
 855     /* Disable interrupts and end the interrupt */
 856     _disable();
 857     HalEndSystemInterrupt(Irql, TrapFrame);
 858
 859     /* Exit the interrupt */
 860     KiEoiHelper(TrapFrame);
 861 }
 862
 863 //
 864 // PERF Code
 865 //
 866 FORCEINLINE
 867 VOID
 868 Ki386PerfEnd(VOID)
 869 {
 870     extern ULONGLONG BootCyclesEnd, BootCycles;
 871     BootCyclesEnd = __rdtsc();
 872     DbgPrint("Boot took %I64u cycles!\n", BootCyclesEnd - BootCycles);
 873     DbgPrint("Interrupts: %u System Calls: %u Context Switches: %u\n",
 874              KeGetCurrentPrcb()->InterruptCount,
 875              KeGetCurrentPrcb()->KeSystemCalls,
 876              KeGetContextSwitches(KeGetCurrentPrcb()));
 877 }
 878
 879 FORCEINLINE
 880 PULONG
 881 KiGetUserModeStackAddress(void)
 882 {
 883     return &(KeGetCurrentThread()->TrapFrame->HardwareEsp);
 884 }
 885
 886 #endif