io.c File Reference

#include <ntoskrnl.h>
#include "newmm.h"
#include <debug.h>
#include <reactos/exeformat.h>

Include dependency graph for io.c:

Go to the source code of this file.

Macros
#define	NDEBUG

Functions
PDEVICE_OBJECT NTAPI	MmGetDeviceObjectForFile (IN PFILE_OBJECT FileObject)
	_Function_class_ (IO_COMPLETION_ROUTINE)
NTSTATUS NTAPI	MiSimpleRead (PFILE_OBJECT FileObject, PLARGE_INTEGER FileOffset, PVOID Buffer, ULONG Length, BOOLEAN Paging, PIO_STATUS_BLOCK ReadStatus)

Variables
KEVENT	CcpLazyWriteEvent

Macro Definition Documentation

NDEBUG

#define NDEBUG

Definition at line 49 of file io.c.

Function Documentation

_Function_class_()

_Function_class_

(

IO_COMPLETION_ROUTINE

)

Definition at line 69 of file io.c.

{
    PMDL Mdl = Irp->MdlAddress;
 
    /* Unlock MDL Pages, page 167. */
    DPRINT("MiSimpleReadComplete %p\n", Irp);
    while (Mdl)
    {
        DPRINT("MDL Unlock %p\n", Mdl);
        MmUnlockPages(Mdl);
        Mdl = Mdl->Next;
    }
 
    /* Check if there's an MDL */
    while ((Mdl = Irp->MdlAddress))
    {
        /* Clear all of them */
        Irp->MdlAddress = Mdl->Next;
        IoFreeMdl(Mdl);
    }
 
    return STATUS_SUCCESS;
}

MiSimpleRead()

NTSTATUS NTAPI MiSimpleRead	(	PFILE_OBJECT	FileObject,
		PLARGE_INTEGER	FileOffset,
		PVOID	Buffer,
		ULONG	Length,
		BOOLEAN	Paging,
		PIO_STATUS_BLOCK	ReadStatus
	)

Definition at line 109 of file io.c.

{
    NTSTATUS Status;
    PIRP Irp = NULL;
    KEVENT ReadWait;
    PDEVICE_OBJECT DeviceObject;
    PIO_STACK_LOCATION IrpSp;
 
    ASSERT(FileObject);
    ASSERT(FileOffset);
    ASSERT(Buffer);
    ASSERT(ReadStatus);
 
    DeviceObject = MmGetDeviceObjectForFile(FileObject);
    ReadStatus->Status = STATUS_INTERNAL_ERROR;
    ReadStatus->Information = 0;
 
    ASSERT(DeviceObject);
 
    DPRINT("PAGING READ: FileObject %p <%wZ> Offset %08x%08x Length %ul\n",
           FileObject,
           &FileObject->FileName,
           FileOffset->HighPart,
           FileOffset->LowPart,
           Length);
 
    KeInitializeEvent(&ReadWait, NotificationEvent, FALSE);
 
    Irp = IoBuildAsynchronousFsdRequest(IRP_MJ_READ,
                                        DeviceObject,
                                        Buffer,
                                        Length,
                                        FileOffset,
                                        ReadStatus);
 
    if (!Irp)
    {
        return STATUS_NO_MEMORY;
    }
 
    Irp->Flags |= (Paging ? IRP_PAGING_IO | IRP_SYNCHRONOUS_PAGING_IO | IRP_NOCACHE : 0) | IRP_SYNCHRONOUS_API;
 
    Irp->UserEvent = &ReadWait;
    Irp->Tail.Overlay.OriginalFileObject = FileObject;
    Irp->Tail.Overlay.Thread = PsGetCurrentThread();
    IrpSp = IoGetNextIrpStackLocation(Irp);
    IrpSp->Control |= SL_INVOKE_ON_SUCCESS | SL_INVOKE_ON_ERROR;
    IrpSp->FileObject = FileObject;
    IrpSp->CompletionRoutine = MiSimpleReadComplete;
 
    /* Non paging case, the FileObject will be dereferenced at completion */
    if (!Paging)
        ObReferenceObject(FileObject);
 
    Status = IoCallDriver(DeviceObject, Irp);
    if (Status == STATUS_PENDING)
    {
        DPRINT("KeWaitForSingleObject(&ReadWait)\n");
        if (!NT_SUCCESS(KeWaitForSingleObject(&ReadWait,
                                              Suspended,
                                              KernelMode,
                                              FALSE,
                                              NULL)))
        {
            DPRINT1("Warning: Failed to wait for synchronous IRP\n");
            ASSERT(FALSE);
            return Status;
        }
    }
 
    DPRINT("Paging IO Done: %08x\n", ReadStatus->Status);
    /* When "ReadStatus->Information > 0" is false and "ReadStatus->Status == STATUS_END_OF_FILE" is true
     * it means that read pointer is out of file, so we must fail */
    Status = ReadStatus->Status == STATUS_END_OF_FILE && ReadStatus->Information > 0 ? STATUS_SUCCESS : ReadStatus->Status;
    return Status;
}

Referenced by CcZeroData(), and ExeFmtpReadFile().

MmGetDeviceObjectForFile()

PDEVICE_OBJECT NTAPI MmGetDeviceObjectForFile

(

IN PFILE_OBJECT

FileObject

)

Definition at line 57 of file io.c.

{
    return IoGetRelatedDeviceObject(FileObject);
}

Referenced by MiSimpleRead().

Variable Documentation

CcpLazyWriteEvent

KEVENT CcpLazyWriteEvent

Definition at line 53 of file io.c.

Referenced by CcInitializeCacheManager().