stackovf.c File Reference

#include "FsRtlP.h"

Go to the source code of this file.

Classes
struct	_STACK_OVERFLOW_ITEM
Defines
#define	MODULE_POOL_TAG   ('srSF')
Typedefs
typedef _STACK_OVERFLOW_ITEM	STACK_OVERFLOW_ITEM
typedef STACK_OVERFLOW_ITEM *	PSTACK_OVERFLOW_ITEM
Functions
VOID	FsRtlStackOverflowRead (IN PVOID Context)
VOID	FsRtlpPostStackOverflow (IN PVOID Context, IN PKEVENT Event, IN PFSRTL_STACK_OVERFLOW_ROUTINE StackOverflowRoutine, IN BOOLEAN PagingFile)
VOID	FsRtlWorkerThread (IN PVOID StartContext)
NTSTATUS	FsRtlInitializeWorkerThread (VOID)
VOID	FsRtlPostStackOverflow (IN PVOID Context, IN PKEVENT Event, IN PFSRTL_STACK_OVERFLOW_ROUTINE StackOverflowRoutine)
VOID	FsRtlPostPagingFileStackOverflow (IN PVOID Context, IN PKEVENT Event, IN PFSRTL_STACK_OVERFLOW_ROUTINE StackOverflowRoutine)
Variables
KQUEUE	FsRtlWorkerQueues [2]

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Define Documentation

#define MODULE_POOL_TAG   ('srSF')

Definition at line 38 of file stackovf.c.

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Typedef Documentation

typedef STACK_OVERFLOW_ITEM* PSTACK_OVERFLOW_ITEM

Definition at line 89 of file stackovf.c. Referenced by FsRtlpPostStackOverflow(), and FsRtlStackOverflowRead().

typedef struct _STACK_OVERFLOW_ITEM STACK_OVERFLOW_ITEM

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Function Documentation

NTSTATUS FsRtlInitializeWorkerThread (  VOID   )

Definition at line 99 of file stackovf.c. References FALSE, FsRtlWorkerQueues, FsRtlWorkerThread(), KeInitializeQueue(), L, NT_SUCCESS, NULL, ObjectAttributes, PsCreateSystemThread(), and TRUE. Referenced by FsRtlInitSystem(). { OBJECT_ATTRIBUTES ObjectAttributes; HANDLE Thread; ULONG i; // // Create worker threads to handle normal and paging overflow reads. // InitializeObjectAttributes(&ObjectAttributes, NULL, 0, NULL, NULL); for (i=0; i < 2; i++) { // // Initialize the FsRtl stack overflow work Queue objects. // KeInitializeQueue(&FsRtlWorkerQueues[i], 0); if (!NT_SUCCESS(PsCreateSystemThread(&Thread, THREAD_ALL_ACCESS, &ObjectAttributes, 0L, NULL, FsRtlWorkerThread, ULongToPtr( i )))) { return FALSE; } } ZwClose( Thread ); return TRUE; }

VOID FsRtlPostPagingFileStackOverflow (  IN PVOID  Context, IN PKEVENT  Event, IN PFSRTL_STACK_OVERFLOW_ROUTINE  StackOverflowRoutine )

Definition at line 177 of file stackovf.c. References Event(), FsRtlpPostStackOverflow(), and TRUE. : This routines posts a stack overflow item to the stack overflow thread and returns. Arguments: Context - Supplies the context to pass to the stack overflow call back routine. If the low order bit is set, then this overflow was a read to a paging file. Event - Supplies a pointer to an event to pass to the stack overflow call back routine. StackOverflowRoutine - Supplies the call back to use when processing the request in the overflow thread. Return Value: None. --*/ { FsRtlpPostStackOverflow( Context, Event, StackOverflowRoutine, TRUE ); return; }

VOID FsRtlPostStackOverflow (  IN PVOID  Context, IN PKEVENT  Event, IN PFSRTL_STACK_OVERFLOW_ROUTINE  StackOverflowRoutine )

Definition at line 139 of file stackovf.c. References Event(), FALSE, and FsRtlpPostStackOverflow(). : This routines posts a stack overflow item to the stack overflow thread and returns. Arguments: Context - Supplies the context to pass to the stack overflow call back routine. If the low order bit is set, then this overflow was a read to a paging file. Event - Supplies a pointer to an event to pass to the stack overflow call back routine. StackOverflowRoutine - Supplies the call back to use when processing the request in the overflow thread. Return Value: None. --*/ { FsRtlpPostStackOverflow( Context, Event, StackOverflowRoutine, FALSE ); return; }

VOID FsRtlpPostStackOverflow (  IN PVOID  Context, IN PKEVENT  Event, IN PFSRTL_STACK_OVERFLOW_ROUTINE  StackOverflowRoutine, IN BOOLEAN  PagingFile )

Definition at line 215 of file stackovf.c. References _STACK_OVERFLOW_ITEM::Context, Event(), _STACK_OVERFLOW_ITEM::Event, ExInitializeWorkItem, FsRtlpAllocatePool, FsRtlStackOverflowRead(), FsRtlWorkerQueues, _STACK_OVERFLOW_ITEM::Item, KeInsertQueue(), _WORK_QUEUE_ITEM::List, NonPagedPool, NonPagedPoolMustSucceed, PSTACK_OVERFLOW_ITEM, and _STACK_OVERFLOW_ITEM::StackOverflowRoutine. Referenced by FsRtlPostPagingFileStackOverflow(), and FsRtlPostStackOverflow(). : This routines posts a stack overflow item to the stack overflow thread and returns. Arguments: Context - Supplies the context to pass to the stack overflow call back routine. If the low order bit is set, then this overflow was a read to a paging file. Event - Supplies a pointer to an event to pass to the stack overflow call back routine. StackOverflowRoutine - Supplies the call back to use when processing the request in the overflow thread. PagingFile - Indicates if the read is destined to a paging file. Return Value: None. --*/ { PSTACK_OVERFLOW_ITEM StackOverflowItem; // // Allocate a stack overflow work item it will later be deallocated by // the stack overflow thread // StackOverflowItem = FsRtlpAllocatePool( PagingFile ? NonPagedPoolMustSucceed : NonPagedPool, sizeof(STACK_OVERFLOW_ITEM) ); // // Fill in the fields in the new item // StackOverflowItem->Context = Context; StackOverflowItem->Event = Event; StackOverflowItem->StackOverflowRoutine = StackOverflowRoutine; ExInitializeWorkItem( &StackOverflowItem->Item, &FsRtlStackOverflowRead, StackOverflowItem ); // // Safely add it to the overflow queue // KeInsertQueue( &FsRtlWorkerQueues[PagingFile], &StackOverflowItem->Item.List ); // // And return to our caller // return; }

VOID FsRtlStackOverflowRead (  IN PVOID  Context  )

Definition at line 294 of file stackovf.c. References _STACK_OVERFLOW_ITEM::Context, _STACK_OVERFLOW_ITEM::Event, ExFreePool(), FSRTL_FSP_TOP_LEVEL_IRP, NULL, PsGetCurrentThread, PSTACK_OVERFLOW_ITEM, and _STACK_OVERFLOW_ITEM::StackOverflowRoutine. Referenced by FsRtlpPostStackOverflow(). : This routine processes all of the stack overflow request posted by the various file systems Arguments: Return Value: None. --*/ { PSTACK_OVERFLOW_ITEM StackOverflowItem; // // Since stack overflow reads are always recursive, set the // TopLevelIrp field appropriately so that recurive reads // from this point will not think they are top level. // PsGetCurrentThread()->TopLevelIrp = FSRTL_FSP_TOP_LEVEL_IRP; // // Get a pointer to the stack overflow item and then call // the callback routine to do the work // StackOverflowItem = (PSTACK_OVERFLOW_ITEM)Context; (StackOverflowItem->StackOverflowRoutine)(StackOverflowItem->Context, StackOverflowItem->Event); // // Deallocate the work item and then go back to the loop to // to wait for another work item // ExFreePool( StackOverflowItem ); PsGetCurrentThread()->TopLevelIrp = (ULONG_PTR)NULL; }

VOID FsRtlWorkerThread (  IN PVOID  StartContext  )

Definition at line 345 of file stackovf.c. References FsRtlWorkerQueues, IRQL_NOT_LESS_OR_EQUAL, KeBugCheckEx(), KeRemoveQueue(), KernelMode, KeSetPriorityThread(), List, NULL, _WORK_QUEUE_ITEM::Parameter, PsGetCurrentThread, TRUE, VOID(), and _WORK_QUEUE_ITEM::WorkerRoutine. Referenced by FsRtlInitializeWorkerThread(). { PLIST_ENTRY Entry; PWORK_QUEUE_ITEM WorkItem; ULONG PagingFile = (ULONG)(ULONG_PTR)StartContext; // // Set our priority to low realtime, or +1 for PagingFile. // (VOID)KeSetPriorityThread( &PsGetCurrentThread()->Tcb, LOW_REALTIME_PRIORITY + PagingFile ); // // Loop forever waiting for a work queue item, calling the processing // routine, and then waiting for another work queue item. // do { // // Wait until something is put in the queue. // // By specifying a wait mode of KernelMode, the thread's kernel stack is // NOT swappable // Entry = KeRemoveQueue(&FsRtlWorkerQueues[PagingFile], KernelMode, NULL); WorkItem = CONTAINING_RECORD(Entry, WORK_QUEUE_ITEM, List); // // Execute the specified routine. // (WorkItem->WorkerRoutine)(WorkItem->Parameter); if (KeGetCurrentIrql() != 0) { KeBugCheckEx( IRQL_NOT_LESS_OR_EQUAL, (ULONG_PTR)WorkItem->WorkerRoutine, (ULONG_PTR)KeGetCurrentIrql(), (ULONG_PTR)WorkItem->WorkerRoutine, (ULONG_PTR)WorkItem ); } } while(TRUE); }

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Variable Documentation

KQUEUE FsRtlWorkerQueues[2]

Definition at line 31 of file stackovf.c. Referenced by FsRtlInitializeWorkerThread(), FsRtlpPostStackOverflow(), and FsRtlWorkerThread().

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