reactos/drivers/filesystems/ext2/src/lock.c

   1 /*
   2  * COPYRIGHT:        See COPYRIGHT.TXT
   3  * PROJECT:          Ext2 File System Driver for WinNT/2K/XP
   4  * FILE:             lock.c
   5  * PROGRAMMER:       Matt Wu <mattwu@163.com>
   6  * HOMEPAGE:         http://www.ext2fsd.com
   7  * UPDATE HISTORY:
   8  */
   9
  10 /* INCLUDES *****************************************************************/
  11
  12 #include "ext2fs.h"
  13
  14 /* GLOBALS ***************************************************************/
  15
  16 extern PEXT2_GLOBAL Ext2Global;
  17
  18 /* DEFINITIONS *************************************************************/
  19
  20 #ifdef ALLOC_PRAGMA
  21 #pragma alloc_text(PAGE, Ext2LockControl)
  22 #endif
  23
  24 NTSTATUS
  25 Ext2LockControl (IN PEXT2_IRP_CONTEXT IrpContext)
  26 {
  27     PDEVICE_OBJECT  DeviceObject = NULL;
  28     PFILE_OBJECT    FileObject = NULL;
  29     PEXT2_FCB       Fcb = NULL;
  30     PIRP            Irp = NULL;
  31
  32     NTSTATUS        Status = STATUS_UNSUCCESSFUL;
  33     BOOLEAN         CompleteContext = TRUE;
  34     BOOLEAN         CompleteIrp = TRUE;
  35     BOOLEAN         bFcbAcquired = FALSE;
  36
  37     _SEH2_TRY {
  38
  39         ASSERT(IrpContext != NULL);
  40
  41         ASSERT((IrpContext->Identifier.Type == EXT2ICX) &&
  42                (IrpContext->Identifier.Size == sizeof(EXT2_IRP_CONTEXT)));
  43
  44         DeviceObject = IrpContext->DeviceObject;
  45
  46         if (IsExt2FsDevice(DeviceObject)) {
  47             Status = STATUS_INVALID_DEVICE_REQUEST;
  48             _SEH2_LEAVE;
  49         }
  50
  51         FileObject = IrpContext->FileObject;
  52
  53         Fcb = (PEXT2_FCB) FileObject->FsContext;
  54         ASSERT(Fcb != NULL);
  55         if (Fcb->Identifier.Type == EXT2VCB) {
  56             Status = STATUS_INVALID_PARAMETER;
  57             _SEH2_LEAVE;
  58         }
  59
  60         ASSERT((Fcb->Identifier.Type == EXT2FCB) &&
  61                (Fcb->Identifier.Size == sizeof(EXT2_FCB)));
  62
  63         if (FlagOn(Fcb->Mcb->FileAttr, FILE_ATTRIBUTE_DIRECTORY)) {
  64             Status = STATUS_INVALID_PARAMETER;
  65             _SEH2_LEAVE;
  66         }
  67
  68         ExAcquireResourceSharedLite(&Fcb->MainResource, TRUE);
  69         bFcbAcquired = TRUE;
  70
  71         Irp = IrpContext->Irp;
  72
  73         CompleteIrp = FALSE;
  74
  75         Status = FsRtlCheckOplock( &Fcb->Oplock,
  76                                    Irp,
  77                                    IrpContext,
  78                                    Ext2OplockComplete,
  79                                    NULL );
  80
  81         if (Status != STATUS_SUCCESS) {
  82             CompleteContext = FALSE;
  83             _SEH2_LEAVE;
  84         }
  85
  86         //
  87         // FsRtlProcessFileLock acquires FileObject->FsContext->Resource while
  88         // modifying the file locks and calls IoCompleteRequest when it's done.
  89         //
  90
  91         Status = FsRtlProcessFileLock(
  92                      &Fcb->FileLockAnchor,
  93                      Irp,
  94                      NULL );
  95 #if EXT2_DEBUG
  96         if (!NT_SUCCESS(Status)) {
  97             DEBUG(DL_ERR, (
  98                       "Ext2LockControl: %-16.16s %-31s Status: %#x ***\n",
  99                       Ext2GetCurrentProcessName(),
 100                       "IRP_MJ_LOCK_CONTROL",
 101                       Status          ));
 102         }
 103 #endif
 104         Fcb->Header.IsFastIoPossible = Ext2IsFastIoPossible(Fcb);
 105
 106     } _SEH2_FINALLY {
 107
 108         if (bFcbAcquired) {
 109             ExReleaseResourceLite(&Fcb->MainResource);
 110         }
 111
 112         if (!IrpContext->ExceptionInProgress) {
 113
 114             if (!CompleteIrp) {
 115                 IrpContext->Irp = NULL;
 116             }
 117
 118             if (CompleteContext) {
 119                 Ext2CompleteIrpContext(IrpContext, Status);
 120             }
 121         }
 122     } _SEH2_END;
 123
 124     return Status;
 125 }