/*++ Copyright (c) 1990 Microsoft Corporation Module Name: thredini.c Abstract: This module implements the machine dependent functions to set the initial context and data alignment handling mode for a process or thread object. Author: David N. Cutler (davec) 1-Apr-1990 Environment: Kernel mode only. Revision History: 3-19-96 Bernard Lint (blint) Conversion to IA64 (from PPC and MIPS versions) --*/ #include "ki.h" VOID KeContextToKframesSpecial ( IN PKTHREAD Thread, IN OUT PKTRAP_FRAME TrapFrame, IN OUT PKEXCEPTION_FRAME ExceptionFrame, IN PCONTEXT ContextFrame, IN ULONG ContextFlags ); // // The following assert macros are used to check that an input object is // really the proper type. // #define ASSERT_PROCESS(E) { \ ASSERT((E)->Header.Type == ProcessObject); \ } #define ASSERT_THREAD(E) { \ ASSERT((E)->Header.Type == ThreadObject); \ } VOID KiInitializeContextThread ( IN PKTHREAD Thread, IN PKSYSTEM_ROUTINE SystemRoutine, IN PKSTART_ROUTINE StartRoutine OPTIONAL, IN PVOID StartContext OPTIONAL, IN PCONTEXT ContextRecord OPTIONAL ) /*++ Routine Description: This function initializes the machine dependent context of a thread object. Actually, what it does is to lay out the stack for the thread so that it contains a stack frame that will be picked up by SwapContext and returned thru, resulting in a transfer of control to KiThreadStartup. In otherwords, we lay out a stack with a stack frame that looks as if SwapContext had been called just before the first instruction in KiThreadStartup. N.B. This function does not check the accessibility of the context record. It is assumed the the caller of this routine is either prepared to handle access violations or has probed and copied the context record as appropriate. N.B. Arguments to the new thread are passed in the Swap Frame preserved registers s0 - s3 which are restored by Swap Context when thread execution begins. Arguments: Thread - Supplies a pointer to a dispatcher object of type thread. SystemRoutine - Supplies a pointer to the system function that is to be called when the thread is first scheduled for execution. N.B. This is the routine entry point, not a function pointer (plabel pointer). StartRoutine - Supplies an optional pointer to a function that is to be called after the system has finished initializing the thread. This parameter is specified if the thread is a system thread and will execute totally in kernel mode. N.B. This is the routine function pointer (plabel pointer). StartContext - Supplies an optional pointer to an arbitrary data structure which will be passed to the StartRoutine as a parameter. This parameter is specified if the thread is a system thread and will execute totally in kernel mode. ContextRecord - Supplies an optional pointer a context frame which contains the initial user mode state of the thread. This parameter is specified if the thread is a user thread and will execute in user mode. If this parameter is not specified, then the Teb parameter is ignored. Return Value: None. --*/ { PKSWITCH_FRAME SwFrame; PKEXCEPTION_FRAME ExFrame; ULONG_PTR InitialStack; PKTRAP_FRAME TrFrame; // // Set up the thread backing store pointers from the initial stack pointers. // InitialStack = (ULONG_PTR)Thread->InitialStack; Thread->InitialBStore = (PVOID)InitialStack; Thread->BStoreLimit = (PVOID)(InitialStack + KERNEL_BSTORE_SIZE); // // If a context frame is specified, then initialize a trap frame and // and an exception frame with the specified user mode context. Also // allocate the switch frame. // if (ARGUMENT_PRESENT(ContextRecord)) { TrFrame = (PKTRAP_FRAME)((InitialStack) - KTHREAD_STATE_SAVEAREA_LENGTH - KTRAP_FRAME_LENGTH); ExFrame = (PKEXCEPTION_FRAME)(((ULONG_PTR)TrFrame + STACK_SCRATCH_AREA - sizeof(KEXCEPTION_FRAME)) & ~((ULONG_PTR)15)); SwFrame = (PKSWITCH_FRAME)(((ULONG_PTR)ExFrame - sizeof(KSWITCH_FRAME)) & ~((ULONG_PTR)15)); KeContextToKframesSpecial(Thread, TrFrame, ExFrame, ContextRecord, ContextRecord->ContextFlags | CONTEXT_CONTROL); // // Set the saved previous processor mode in the trap frame and the // previous processor mode in the thread object to user mode. // TrFrame->PreviousMode = UserMode; Thread->PreviousMode = UserMode; // // Initialize the FPSR for user mode // TrFrame->StFPSR = USER_FPSR_INITIAL; // // Initialize the user TEB pointer in the trap frame // TrFrame->IntTeb = (ULONGLONG)Thread->Teb; } else { SwFrame = (PKSWITCH_FRAME)((InitialStack) - sizeof(KSWITCH_FRAME)); // // Set the previous mode in thread object to kernel. // Thread->PreviousMode = KernelMode; } // // Initialize context switch frame and set thread start up parameters. // The Swap return pointer and SystemRoutine are entry points, not function pointers. // RtlZeroMemory((PVOID)SwFrame, sizeof(KSWITCH_FRAME)); // init all to 0 SwFrame->SwitchRp = ((PPLABEL_DESCRIPTOR)KiThreadStartup)->EntryPoint; SwFrame->SwitchExceptionFrame.IntS0 = (ULONGLONG)ContextRecord; SwFrame->SwitchExceptionFrame.IntS1 = (ULONGLONG)StartContext; SwFrame->SwitchExceptionFrame.IntS2 = (ULONGLONG)StartRoutine; SwFrame->SwitchExceptionFrame.IntS3 = ((PPLABEL_DESCRIPTOR)SystemRoutine)->EntryPoint; SwFrame->SwitchFPSR = FPSR_FOR_KERNEL; SwFrame->SwitchBsp = (ULONGLONG)Thread->InitialBStore; Thread->KernelBStore = Thread->InitialBStore; Thread->KernelStack = (PVOID)((ULONG_PTR)SwFrame-STACK_SCRATCH_AREA); if (Thread->Teb) { PKAPPLICATION_REGISTERS AppRegs; AppRegs = GET_APPLICATION_REGISTER_SAVEAREA(Thread->StackBase); AppRegs->Ar21 = 0; // ContextRecord->StFCR; // // Ar24 is EFlags. Need to set up a value that is good for iVE // Based on i386 eflags SANITIZE_FLAGS // This is simplier, though since never running i386 in kernel // mode AppRegs->Ar24 = EFLAGS_INTERRUPT_MASK | (((ULONG) ContextRecord->Eflag) & EFLAGS_USER_SANITIZE); AppRegs->Ar25 = USER_CODE_DESCRIPTOR; AppRegs->Ar26 = USER_DATA_DESCRIPTOR; AppRegs->Ar27 = (((ULONGLONG) CR4_VME | CR4_FXSR | CR4_XMMEXCPT) << 32) | (CR0_PE | CFLG_II); AppRegs->Ar28 = SANITIZE_AR28_FSR (ContextRecord->StFSR, UserMode); AppRegs->Ar29 = SANITIZE_AR29_FIR (ContextRecord->StFIR, UserMode); AppRegs->Ar30 = SANITIZE_AR30_FDR (ContextRecord->StFDR, UserMode); } return; } BOOLEAN KeSetAutoAlignmentProcess ( IN PRKPROCESS Process, IN BOOLEAN Enable ) /*++ Routine Description: This function sets the data alignment handling mode for the specified process and returns the previous data alignment handling mode. Arguments: Process - Supplies a pointer to a dispatcher object of type process. Enable - Supplies a boolean value that determines the handling of data alignment exceptions for the process. A value of TRUE causes all data alignment exceptions to be automatically handled by the kernel. A value of FALSE causes all data alignment exceptions to be actually raised as exceptions. Return Value: A value of TRUE is returned if data alignment exceptions were previously automatically handled by the kernel. Otherwise, a value of FALSE is returned. --*/ { KIRQL OldIrql; BOOLEAN Previous; ASSERT_PROCESS(Process); // // Raise IRQL to dispatcher level and lock dispatcher database. // KiLockDispatcherDatabase(&OldIrql); // // Capture the previous data alignment handling mode and set the // specified data alignment mode. // Previous = Process->AutoAlignment; Process->AutoAlignment = Enable; // // Unlock dispatcher database, lower IRQL to its previous value, and // return the previous data alignment mode. // KiUnlockDispatcherDatabase(OldIrql); return Previous; } BOOLEAN KeSetAutoAlignmentThread ( IN PKTHREAD Thread, IN BOOLEAN Enable ) /*++ Routine Description: This function sets the data alignment handling mode for the specified thread and returns the previous data alignment handling mode. Arguments: Thread - Supplies a pointer to a dispatcher object of type thread. Enable - Supplies a boolean value that determines the handling of data alignment exceptions for the thread. A value of TRUE causes all data alignment exceptions to be automatically handled by the kernel. A value of FALSE causes all data alignment exceptions to be actually raised as exceptions. Return Value: A value of TRUE is returned if data alignment exceptions were previously automatically handled by the kernel. Otherwise, a value of FALSE is returned. --*/ { KIRQL OldIrql; BOOLEAN Previous; ASSERT_THREAD(Thread); // // Raise IRQL to dispatcher level and lock dispatcher database. // KiLockDispatcherDatabase(&OldIrql); // // Capture the previous data alignment handling mode and set the // specified data alignment mode. // Previous = Thread->AutoAlignment; Thread->AutoAlignment = Enable; // // Unlock dispatcher database, lower IRQL to its previous value, and // return the previous data alignment mode. // KiUnlockDispatcherDatabase(OldIrql); return Previous; }