/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS kernel
- * FILE: drivers/fs/vfat/rw.c
+ * FILE: drivers/filesystems/fastfat/rw.c
* PURPOSE: VFAT Filesystem
* PROGRAMMER: Jason Filby (jasonfilby@yahoo.com)
+ * Pierre Schweitzer (pierre@reactos.org)
*
*/
*/
/* #define DEBUG_VERIFY_OFFSET_CACHING */
+/* Arbitrary, taken from MS FastFAT, should be
+ * refined given what we experience in common
+ * out of stack operations
+ */
+#define OVERFLOW_READ_THRESHHOLD 0xE00
+
/* FUNCTIONS *****************************************************************/
/*
Status = IrpContext->Irp->IoStatus.Status;
}
}
+
return Status;
}
+NTSTATUS
+VfatCommonRead(
+ PVFAT_IRP_CONTEXT IrpContext)
+{
+ PVFATFCB Fcb;
+ PVOID Buffer;
+ NTSTATUS Status;
+ ULONG Length = 0;
+ ULONG BytesPerSector;
+ LARGE_INTEGER ByteOffset;
+ ULONG ReturnedLength = 0;
+ BOOLEAN PagingIo, CanWait, IsVolume, NoCache;
+
+ PagingIo = BooleanFlagOn(IrpContext->Irp->Flags, IRP_PAGING_IO);
+ CanWait = BooleanFlagOn(IrpContext->Flags, IRPCONTEXT_CANWAIT);
+ NoCache = BooleanFlagOn(IrpContext->Irp->Flags, IRP_NOCACHE);
+ Fcb = IrpContext->FileObject->FsContext;
+ IsVolume = BooleanFlagOn(Fcb->Flags, FCB_IS_VOLUME);
+
+ ByteOffset = IrpContext->Stack->Parameters.Read.ByteOffset;
+ Length = IrpContext->Stack->Parameters.Read.Length;
+ BytesPerSector = IrpContext->DeviceExt->FatInfo.BytesPerSector;
+
+ if (!PagingIo &&
+ FsRtlAreThereCurrentFileLocks(&Fcb->FileLock))
+ {
+ if (!FsRtlCheckLockForReadAccess(&Fcb->FileLock, IrpContext->Irp))
+ {
+ return STATUS_FILE_LOCK_CONFLICT;
+ }
+ }
+
+ Buffer = VfatGetUserBuffer(IrpContext->Irp, PagingIo);
+
+ if (!PagingIo && !NoCache && !IsVolume)
+ {
+ // cached read
+ Status = STATUS_SUCCESS;
+ if (ByteOffset.u.LowPart + Length > Fcb->RFCB.FileSize.u.LowPart)
+ {
+ Length = Fcb->RFCB.FileSize.u.LowPart - ByteOffset.u.LowPart;
+ Status = /*STATUS_END_OF_FILE*/STATUS_SUCCESS;
+ }
+
+ vfatAddToStat(IrpContext->DeviceExt, Base.UserFileReads, 1);
+ vfatAddToStat(IrpContext->DeviceExt, Base.UserFileReadBytes, Length);
+
+ _SEH2_TRY
+ {
+ if (IrpContext->FileObject->PrivateCacheMap == NULL)
+ {
+ CcInitializeCacheMap(IrpContext->FileObject,
+ (PCC_FILE_SIZES)(&Fcb->RFCB.AllocationSize),
+ FALSE,
+ &(VfatGlobalData->CacheMgrCallbacks),
+ Fcb);
+ }
+
+ if (!CcCopyRead(IrpContext->FileObject,
+ &ByteOffset,
+ Length,
+ CanWait,
+ Buffer,
+ &IrpContext->Irp->IoStatus))
+ {
+ ASSERT(!CanWait);
+ Status = STATUS_PENDING;
+ goto ByeBye;
+ }
+ }
+ _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
+ {
+ Status = _SEH2_GetExceptionCode();
+ goto ByeBye;
+ }
+ _SEH2_END;
+
+ if (!NT_SUCCESS(IrpContext->Irp->IoStatus.Status))
+ {
+ Status = IrpContext->Irp->IoStatus.Status;
+ }
+ }
+ else
+ {
+ // non cached read
+ Status = VfatLockUserBuffer(IrpContext->Irp, Length, IoWriteAccess);
+ if (!NT_SUCCESS(Status))
+ {
+ goto ByeBye;
+ }
+
+ if (ByteOffset.QuadPart + Length > ROUND_UP_64(Fcb->RFCB.FileSize.QuadPart, BytesPerSector))
+ {
+ Length = (ULONG)(ROUND_UP_64(Fcb->RFCB.FileSize.QuadPart, BytesPerSector) - ByteOffset.QuadPart);
+ }
+
+ if (!IsVolume)
+ {
+ vfatAddToStat(IrpContext->DeviceExt, Fat.NonCachedReads, 1);
+ vfatAddToStat(IrpContext->DeviceExt, Fat.NonCachedReadBytes, Length);
+ }
+ else
+ {
+ vfatAddToStat(IrpContext->DeviceExt, Base.MetaDataReads, 1);
+ vfatAddToStat(IrpContext->DeviceExt, Base.MetaDataReadBytes, Length);
+ }
+
+ Status = VfatReadFileData(IrpContext, Length, ByteOffset, &ReturnedLength);
+ if (NT_SUCCESS(Status))
+ {
+ IrpContext->Irp->IoStatus.Information = ReturnedLength;
+ }
+ }
+
+ByeBye:
+ return Status;
+}
+
+VOID
+NTAPI
+VfatStackOverflowRead(
+ PVOID Context,
+ IN PKEVENT Event)
+{
+ PVFAT_IRP_CONTEXT IrpContext;
+
+ IrpContext = Context;
+ /* In a separate thread, we can wait and resources got locked */
+ SetFlag(IrpContext->Flags, IRPCONTEXT_CANWAIT);
+
+ /* Perform the read operation */
+ DPRINT1("Performing posted read\n");
+ VfatCommonRead(IrpContext);
+
+ KeSetEvent(Event, 0, FALSE);
+}
+
+VOID
+VfatPostRead(
+ PVFAT_IRP_CONTEXT IrpContext,
+ PERESOURCE Lock,
+ BOOLEAN PagingIo)
+{
+ KEVENT Event;
+
+ KeInitializeEvent(&Event, NotificationEvent, FALSE);
+
+ ExAcquireResourceSharedLite(Lock, TRUE);
+
+ /* If paging IO, call the non failing but blocking routine */
+ if (PagingIo)
+ {
+ FsRtlPostPagingFileStackOverflow(IrpContext, &Event, VfatStackOverflowRead);
+ }
+ else
+ {
+ FsRtlPostStackOverflow(IrpContext, &Event, VfatStackOverflowRead);
+ }
+
+ /* Wait till it's done */
+ KeWaitForSingleObject(&Event, Executive, KernelMode, FALSE, NULL);
+}
+
NTSTATUS
VfatRead(
PVFAT_IRP_CONTEXT IrpContext)
NTSTATUS Status;
PVFATFCB Fcb;
ULONG Length = 0;
- ULONG ReturnedLength = 0;
PERESOURCE Resource = NULL;
LARGE_INTEGER ByteOffset;
- PVOID Buffer;
ULONG BytesPerSector;
BOOLEAN PagingIo, CanWait, IsVolume, NoCache;
Resource = &Fcb->MainResource;
}
- if (!ExAcquireResourceSharedLite(Resource, CanWait))
- {
- Resource = NULL;
- Status = STATUS_PENDING;
- goto ByeBye;
- }
-
- if (!PagingIo &&
- FsRtlAreThereCurrentFileLocks(&Fcb->FileLock))
- {
- if (!FsRtlCheckLockForReadAccess(&Fcb->FileLock, IrpContext->Irp))
- {
- Status = STATUS_FILE_LOCK_CONFLICT;
- goto ByeBye;
- }
- }
-
- Buffer = VfatGetUserBuffer(IrpContext->Irp, PagingIo);
-
- if (!PagingIo && !NoCache && !IsVolume)
+ /* Are we out of stack for the rest of the operation? */
+ if (IoGetRemainingStackSize() < OVERFLOW_READ_THRESHHOLD)
{
- // cached read
- Status = STATUS_SUCCESS;
- if (ByteOffset.u.LowPart + Length > Fcb->RFCB.FileSize.u.LowPart)
- {
- Length = Fcb->RFCB.FileSize.u.LowPart - ByteOffset.u.LowPart;
- Status = /*STATUS_END_OF_FILE*/STATUS_SUCCESS;
- }
-
- vfatAddToStat(IrpContext->DeviceExt, Base.UserFileReads, 1);
- vfatAddToStat(IrpContext->DeviceExt, Base.UserFileReadBytes, Length);
-
- _SEH2_TRY
- {
- if (IrpContext->FileObject->PrivateCacheMap == NULL)
- {
- CcInitializeCacheMap(IrpContext->FileObject,
- (PCC_FILE_SIZES)(&Fcb->RFCB.AllocationSize),
- FALSE,
- &(VfatGlobalData->CacheMgrCallbacks),
- Fcb);
- }
-
- if (!CcCopyRead(IrpContext->FileObject,
- &ByteOffset,
- Length,
- CanWait,
- Buffer,
- &IrpContext->Irp->IoStatus))
- {
- ASSERT(!CanWait);
- Status = STATUS_PENDING;
- goto ByeBye;
- }
- }
- _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
- {
- Status = _SEH2_GetExceptionCode();
- goto ByeBye;
- }
- _SEH2_END;
-
- if (!NT_SUCCESS(IrpContext->Irp->IoStatus.Status))
- {
- Status = IrpContext->Irp->IoStatus.Status;
- }
- }
- else
- {
- // non cached read
+ /* Lock the buffer */
Status = VfatLockUserBuffer(IrpContext->Irp, Length, IoWriteAccess);
if (!NT_SUCCESS(Status))
{
- goto ByeBye;
+ return Status;
}
- if (ByteOffset.QuadPart + Length > ROUND_UP_64(Fcb->RFCB.FileSize.QuadPart, BytesPerSector))
- {
- Length = (ULONG)(ROUND_UP_64(Fcb->RFCB.FileSize.QuadPart, BytesPerSector) - ByteOffset.QuadPart);
- }
+ /* And post the read to the overflow thread */
+ VfatPostRead(IrpContext, Resource, PagingIo);
- if (!IsVolume)
- {
- vfatAddToStat(IrpContext->DeviceExt, Fat.NonCachedReads, 1);
- vfatAddToStat(IrpContext->DeviceExt, Fat.NonCachedReadBytes, Length);
- }
- else
- {
- vfatAddToStat(IrpContext->DeviceExt, Base.MetaDataReads, 1);
- vfatAddToStat(IrpContext->DeviceExt, Base.MetaDataReadBytes, Length);
- }
+ /* Return the appropriate status */
+ return IrpContext->Irp->IoStatus.Status;
+ }
- Status = VfatReadFileData(IrpContext, Length, ByteOffset, &ReturnedLength);
- if (NT_SUCCESS(Status))
- {
- IrpContext->Irp->IoStatus.Information = ReturnedLength;
- }
+ if (!ExAcquireResourceSharedLite(Resource, CanWait))
+ {
+ Resource = NULL;
+ Status = STATUS_PENDING;
+ goto ByeBye;
}
+ Status = VfatCommonRead(IrpContext);
+
ByeBye:
if (Resource)
{
}
}
+ if (!NoCache && !CcCanIWrite(IrpContext->FileObject, Length, CanWait,
+ BooleanFlagOn(IrpContext->Flags, IRPCONTEXT_DEFERRED_WRITE)))
+ {
+ BOOLEAN Retrying;
+
+ Retrying = BooleanFlagOn(IrpContext->Flags, IRPCONTEXT_DEFERRED_WRITE);
+ SetFlag(IrpContext->Flags, IRPCONTEXT_DEFERRED_WRITE);
+
+ Status = STATUS_PENDING;
+ CcDeferWrite(IrpContext->FileObject, VfatHandleDeferredWrite,
+ IrpContext, NULL, Length, Retrying);
+
+ DPRINT1("Dererring write!\n");
+
+ goto ByeBye;
+ }
+
if (IsVolume)
{
Resource = &IrpContext->DeviceExt->DirResource;
ByteOffset.u.LowPart + Length > Fcb->RFCB.FileSize.u.LowPart)
{
LARGE_INTEGER AllocationSize;
+
+ if (!ExAcquireResourceExclusiveLite(&IrpContext->DeviceExt->DirResource, CanWait))
+ {
+ Status = STATUS_PENDING;
+ goto ByeBye;
+ }
+
AllocationSize.QuadPart = ByteOffset.u.LowPart + Length;
Status = VfatSetAllocationSizeInformation(IrpContext->FileObject, Fcb,
IrpContext->DeviceExt, &AllocationSize);
+
+ ExReleaseResourceLite(&IrpContext->DeviceExt->DirResource);
+
if (!NT_SUCCESS (Status))
{
goto ByeBye;
Filter = FILE_NOTIFY_CHANGE_LAST_WRITE | FILE_NOTIFY_CHANGE_ATTRIBUTES;
if (ByteOffset.QuadPart != OldFileSize.QuadPart) Filter |= FILE_NOTIFY_CHANGE_SIZE;
- FsRtlNotifyFullReportChange(IrpContext->DeviceExt->NotifySync,
- &(IrpContext->DeviceExt->NotifyList),
- (PSTRING)&Fcb->PathNameU,
- Fcb->PathNameU.Length - Fcb->LongNameU.Length,
- NULL,
- NULL,
- Filter,
- FILE_ACTION_MODIFIED,
- NULL);
+ vfatReportChange(IrpContext->DeviceExt, Fcb, Filter, FILE_ACTION_MODIFIED);
}
}
projects / reactos.git / blobdiff