test: i386/thredini.c File Reference

00081 : 00082 00083 This function initializes the machine dependent context of a thread object. 00084 00085 N.B. This function does not check the accessibility of the context record. 00086 It is assumed the the caller of this routine is either prepared to 00087 handle access violations or has probed and copied the context record 00088 as appropriate. 00089 00090 Arguments: 00091 00092 Thread - Supplies a pointer to a dispatcher object of type thread. 00093 00094 SystemRoutine - Supplies a pointer to the system function that is to be 00095 called when the thread is first scheduled for execution. 00096 00097 StartRoutine - Supplies an optional pointer to a function that is to be 00098 called after the system has finished initializing the thread. This 00099 parameter is specified if the thread is a system thread and will 00100 execute totally in kernel mode. 00101 00102 StartContext - Supplies an optional pointer to an arbitrary data structure 00103 which will be passed to the StartRoutine as a parameter. This 00104 parameter is specified if the thread is a system thread and will 00105 execute totally in kernel mode. 00106 00107 ContextFrame - Supplies an optional pointer a context frame which contains 00108 the initial user mode state of the thread. This parameter is specified 00109 if the thread is a user thread and will execute in user mode. If this 00110 parameter is not specified, then the Teb parameter is ignored. 00111 00112 Return Value: 00113 00114 None. 00115 00116 --*/ 00117 00118 { 00119 PFX_SAVE_AREA NpxFrame; 00120 PKSWITCHFRAME SwitchFrame; 00121 PKTRAP_FRAME TrFrame; 00122 PULONG PSystemRoutine; 00123 PULONG PStartRoutine; 00124 PULONG PStartContext; 00125 PULONG PUserContextFlag; 00126 ULONG ContextFlags; 00127 CONTEXT Context2; 00128 PCONTEXT ContextFrame2 = NULL; 00129 PFXSAVE_FORMAT PFxSaveArea; 00130 00131 // 00132 // If a context frame is specified, then initialize a trap frame and 00133 // and an exception frame with the specified user mode context. 00134 // 00135 00136 if (ARGUMENT_PRESENT(ContextFrame)) { 00137 00138 RtlMoveMemory(&Context2, ContextFrame, sizeof(CONTEXT)); 00139 ContextFrame2 = &Context2; 00140 ContextFlags = CONTEXT_CONTROL; 00141 00142 // 00143 // The 80387 save area is at the very base of the kernel stack. 00144 // 00145 00146 NpxFrame = (PFX_SAVE_AREA)(((ULONG)(Thread->InitialStack) - 00147 sizeof(FX_SAVE_AREA))); 00148 00149 // 00150 // Load up an initial NPX state. 00151 // 00152 00153 if (KeI386XMMIPresent == TRUE) { 00154 PFxSaveArea = (PFXSAVE_FORMAT)ContextFrame2->ExtendedRegisters; 00155 00156 PFxSaveArea->ControlWord = 0x27f; // like fpinit but 64bit mode 00157 PFxSaveArea->StatusWord = 0; 00158 PFxSaveArea->TagWord = 0; 00159 PFxSaveArea->ErrorOffset = 0; 00160 PFxSaveArea->ErrorSelector = 0; 00161 PFxSaveArea->DataOffset = 0; 00162 PFxSaveArea->DataSelector = 0; 00163 PFxSaveArea->MXCsr = 0x1f80; // mask all the exceptions 00164 } else { 00165 ContextFrame2->FloatSave.ControlWord = 0x27f; // like fpinit but 64bit mode 00166 ContextFrame2->FloatSave.StatusWord = 0; 00167 ContextFrame2->FloatSave.TagWord = 0xffff; 00168 ContextFrame2->FloatSave.ErrorOffset = 0; 00169 ContextFrame2->FloatSave.ErrorSelector = 0; 00170 ContextFrame2->FloatSave.DataOffset = 0; 00171 ContextFrame2->FloatSave.DataSelector = 0; 00172 } 00173 00174 00175 if (KeI386NpxPresent) { 00176 ContextFrame2->FloatSave.Cr0NpxState = 0; 00177 NpxFrame->Cr0NpxState = 0; 00178 NpxFrame->NpxSavedCpu = 0; 00179 if (KeI386XMMIPresent == TRUE) { 00180 ContextFlags |= CONTEXT_EXTENDED_REGISTERS; 00181 } else { 00182 ContextFlags |= CONTEXT_FLOATING_POINT; 00183 } 00184 00185 // 00186 // Threads NPX state is not in the coprocessor. 00187 // 00188 00189 Thread->NpxState = NPX_STATE_NOT_LOADED; 00190 Thread->NpxIrql = PASSIVE_LEVEL; 00191 00192 } else { 00193 NpxFrame->Cr0NpxState = CR0_EM; 00194 00195 // 00196 // Threads NPX state is not in the coprocessor. 00197 // In the emulator case, do not set the CR0_EM bit as their 00198 // emulators may not want exceptions on FWAIT instructions. 00199 // 00200 00201 Thread->NpxState = NPX_STATE_NOT_LOADED & ~CR0_MP; 00202 } 00203 00204 // 00205 // Force debug registers off. They won't work anyway from an 00206 // initial frame, debuggers must set a hard breakpoint in the target 00207 // 00208 00209 ContextFrame2->Dr0 = 0; 00210 ContextFrame2->Dr1 = 0; 00211 ContextFrame2->Dr2 = 0; 00212 ContextFrame2->Dr3 = 0; 00213 ContextFrame2->Dr6 = 0; 00214 ContextFrame2->Dr7 = 0; 00215 ContextFrame2->ContextFlags &= ~(CONTEXT_DEBUG_REGISTERS); 00216 #if 0 00217 // 00218 // If AutoAlignment is FALSE, we want to set the Alignment Check bit 00219 // in Eflags, so we will get alignment faults. 00220 // 00221 00222 if (Thread->AutoAlignment == FALSE) { 00223 ContextFrame2->EFlags |= EFLAGS_ALIGN_CHECK; 00224 } 00225 #endif 00226 // 00227 // If the thread is set 00228 00229 TrFrame = (PKTRAP_FRAME)(((ULONG)NpxFrame - KTRAP_FRAME_LENGTH)); 00230 00231 // Space for arguments to KiThreadStartup. Order is important, 00232 // Since args are passed on stack through KiThreadStartup to 00233 // PStartRoutine with PStartContext as an argument. 00234 00235 PUserContextFlag = (PULONG)TrFrame - 1; 00236 PStartContext = PUserContextFlag - 1; 00237 PStartRoutine = PStartContext - 1; 00238 PSystemRoutine = PStartRoutine - 1; 00239 00240 SwitchFrame = (PKSWITCHFRAME)((PUCHAR)PSystemRoutine - 00241 sizeof(KSWITCHFRAME)); 00242 00243 // 00244 // Copy information from the specified context frame to the trap and 00245 // exception frames. 00246 // 00247 00248 KeContextToKframes(TrFrame, NULL, ContextFrame2, 00249 ContextFrame2->ContextFlags | ContextFlags, 00250 UserMode); 00251 00252 TrFrame->HardwareSegSs |= RPL_MASK; 00253 TrFrame->SegDs |= RPL_MASK; 00254 TrFrame->SegEs |= RPL_MASK; 00255 00256 #if DBG 00257 TrFrame->DbgArgMark = 0xBADB0D00; 00258 #endif 00259 00260 // 00261 // Tell KiThreadStartup that a user context is present. 00262 // 00263 00264 *PUserContextFlag = 1; 00265 00266 00267 // 00268 // Initialize the kernel mode ExceptionList pointer 00269 // 00270 00271 TrFrame->ExceptionList = EXCEPTION_CHAIN_END; 00272 00273 // 00274 // Initialize the saved previous processor mode. 00275 // 00276 00277 TrFrame->PreviousPreviousMode = UserMode; 00278 00279 // 00280 // Set the previous mode in thread object to user. 00281 // 00282 00283 Thread->PreviousMode = UserMode; 00284 00285 00286 } else { 00287 00288 // 00289 // Dummy floating save area. Kernel threads don't have or use 00290 // the floating point - the dummy save area is make the stacks 00291 // consistent. 00292 // 00293 00294 NpxFrame = (PFX_SAVE_AREA)(((ULONG)(Thread->InitialStack) - 00295 sizeof(FX_SAVE_AREA))); 00296 00297 // 00298 // Load up an initial NPX state. 00299 // 00300 RtlZeroMemory((PVOID)NpxFrame, sizeof(FX_SAVE_AREA)); 00301 00302 if (KeI386FxsrPresent == TRUE) { 00303 NpxFrame->U.FxArea.ControlWord = 0x27f;//like fpinit but 64bit mode 00304 NpxFrame->U.FxArea.MXCsr = 0x1f80;// mask all the exceptions 00305 } else { 00306 NpxFrame->U.FnArea.ControlWord = 0x27f;//like fpinit but 64bit mode 00307 NpxFrame->U.FnArea.TagWord = 0xffff; 00308 } 00309 00310 // 00311 // Threads NPX state is not in the coprocessor. 00312 // 00313 00314 Thread->NpxState = NPX_STATE_NOT_LOADED; 00315 00316 // 00317 // Space for arguments to KiThreadStartup. 00318 // Order of fields in the switchframe is important, 00319 // Since args are passed on stack through KiThreadStartup to 00320 // PStartRoutine with PStartContext as an argument. 00321 // 00322 00323 PUserContextFlag = (PULONG)((ULONG)NpxFrame) - 1; 00324 00325 PStartContext = PUserContextFlag - 1; 00326 PStartRoutine = PStartContext - 1; 00327 PSystemRoutine = PStartRoutine - 1; 00328 00329 SwitchFrame = (PKSWITCHFRAME)((PUCHAR)PSystemRoutine - 00330 sizeof(KSWITCHFRAME)); 00331 00332 00333 // 00334 // Tell KiThreadStartup that a user context is NOT present. 00335 // 00336 00337 *PUserContextFlag = 0; 00338 00339 00340 // 00341 // Set the previous mode in thread object to kernel. 00342 // 00343 00344 Thread->PreviousMode = KernelMode; 00345 } 00346 00347 // 00348 // Set up thread start parameters. 00349 // (UserContextFlag set above) 00350 // 00351 00352 *PStartContext = (ULONG)StartContext; 00353 *PStartRoutine = (ULONG)StartRoutine; 00354 *PSystemRoutine = (ULONG)SystemRoutine; 00355 00356 00357 // 00358 // Set up switch frame. Assume the thread doesn't use the 80387; 00359 // if it ever does (and there is one), these flags will get reset. 00360 // Each thread starts with these same flags set, regardless of 00361 // whether the hardware exists or not. 00362 // 00363 00364 SwitchFrame->RetAddr = (ULONG)KiThreadStartup; 00365 00366 SwitchFrame->Eflags = EFLAGS_INTERRUPT_MASK; 00367 00368 #if 0 00369 // 00370 // If AutoAlignment is FALSE, we want to set the Alignment Check bit 00371 // in Eflags, so we will get alignment faults. 00372 // 00373 00374 if (Thread->AutoAlignment == FALSE) { 00375 SwitchFrame->Eflags |= EFLAGS_ALIGN_CHECK; 00376 } 00377 #endif 00378 00379 SwitchFrame->ExceptionList = (ULONG)(EXCEPTION_CHAIN_END); 00380 00381 // 00382 // Set the initial kernel stack pointer. 00383 // 00384 00385 //DbgPrint("KiInitializeContextThread Thread %08x SwitchFrame %08x\n", Thread, SwitchFrame); 00386 //DbgPrint("PSystemRoutine %08x PStartRoutine %08x PStartContext %08x\n", *PSystemRoutine, *PStartRoutine, *PStartContext); 00387 00388 Thread->KernelStack = (PVOID)SwitchFrame; 00389 return; 00390 }


Defines
#define	ASSERT_PROCESS(E)
#define	ASSERT_THREAD(E)
#define	ALIGN_DOWN(address, amt) ((ULONG)(address) & ~(( amt ) - 1))
#define	ALIGN_UP(address, amt) (ALIGN_DOWN( (address + (amt) - 1), (amt) ))
Functions
VOID	KepSetAlignmentSpecialApc (IN PKAPC Apc, IN PKNORMAL_ROUTINE NormalRoutine, IN PVOID NormalContext, IN PVOID SystemArgument1, IN PVOID SystemArgument2)
VOID	KiInitializeContextThread (IN PKTHREAD Thread, IN PKSYSTEM_ROUTINE SystemRoutine, IN PKSTART_ROUTINE StartRoutine OPTIONAL, IN PVOID StartContext OPTIONAL, IN PCONTEXT ContextFrame OPTIONAL)
BOOLEAN	KeSetAutoAlignmentProcess (IN PKPROCESS Process, IN BOOLEAN Enable)
BOOLEAN	KeSetAutoAlignmentThread (IN PKTHREAD Thread, IN BOOLEAN Enable)
Variables
BOOLEAN	KeI386XMMIPresent

thredini.c File Reference

Defines

Functions

Variables

Define Documentation

Function Documentation

Variable Documentation