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2111 lines
56 KiB
2111 lines
56 KiB
/*++
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Copyright (c) 1996-2000 Microsoft Corporation
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Module Name:
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DevIoSup.c
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Abstract:
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This module implements the low lever disk read/write support for Udfs.
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// @@BEGIN_DDKSPLIT
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Author:
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Dan Lovinger [DanLo] 11-Jun-1996
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Tom Jolly [tomjolly] 21-Jan-2000
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Revision History:
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// @@END_DDKSPLIT
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--*/
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#include "UdfProcs.h"
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//
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// The Bug check file id for this module
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//
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#define BugCheckFileId (UDFS_BUG_CHECK_DEVIOSUP)
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//
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// The local debug trace level
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//
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#define Dbg (UDFS_DEBUG_LEVEL_DEVIOSUP)
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//
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// Local structure definitions
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//
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//
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// An array of these structures is passed to UdfMultipleAsync describing
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// a set of runs to execute in parallel.
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//
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typedef struct _IO_RUN {
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//
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// Disk offset to read from and number of bytes to read. These
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// must be a multiple of a sector and the disk offset is also a
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// multiple of sector.
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//
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LONGLONG DiskOffset;
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ULONG DiskByteCount;
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//
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// Current position in user buffer. This is the final destination for
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// this portion of the Io transfer.
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//
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PVOID UserBuffer;
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//
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// Buffer to perform the transfer to. If this is the same as the
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// user buffer above then we are using the user's buffer. Otherwise
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// we either allocated a temporary buffer or are using a different portion
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// of the user's buffer.
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//
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// TransferBuffer - Read full sectors into this location. This can
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// be a pointer into the user's buffer at the exact location the
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// data should go. It can also be an earlier point in the user's
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// buffer if the complete I/O doesn't start on a sector boundary.
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// It may also be a pointer into an allocated buffer.
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//
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// TransferByteCount - Count of bytes to transfer to user's buffer. A
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// value of zero indicates that we did do the transfer into the
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// user's buffer directly.
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//
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// TransferBufferOffset - Offset in this buffer to begin the transfer
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// to the user's buffer.
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//
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PVOID TransferBuffer;
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ULONG TransferByteCount;
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ULONG TransferBufferOffset;
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//
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// This is the Mdl describing the locked pages in memory. It may
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// be allocated to describe the allocated buffer. Or it may be
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// the Mdl in the originating Irp. The MdlOffset is the offset of
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// the current buffer from the beginning of the buffer described by
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// the Mdl below. If the TransferMdl is not the same as the Mdl
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// in the user's Irp then we know we have allocated it.
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//
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PMDL TransferMdl;
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PVOID TransferVirtualAddress;
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//
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// Associated Irp used to perform the Io.
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//
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PIRP SavedIrp;
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} IO_RUN;
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typedef IO_RUN *PIO_RUN;
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#define MAX_PARALLEL_IOS 5
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//
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// Local support routines
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//
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BOOLEAN
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UdfPrepareBuffers (
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IN PIRP_CONTEXT IrpContext,
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IN PIRP Irp,
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IN PFCB Fcb,
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IN PCCB Ccb,
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IN PVOID UserBuffer,
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IN ULONG UserBufferOffset,
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IN LONGLONG StartingOffset,
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IN ULONG ByteCount,
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IN PIO_RUN IoRuns,
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IN PULONG RunCount,
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IN PULONG ThisByteCount,
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OUT PBOOLEAN SparseRuns
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);
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BOOLEAN
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UdfFinishBuffers (
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IN PIRP_CONTEXT IrpContext,
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IN PIO_RUN IoRuns,
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IN ULONG RunCount,
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IN BOOLEAN FinalCleanup
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);
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VOID
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UdfMultipleAsync (
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IN PIRP_CONTEXT IrpContext,
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IN ULONG RunCount,
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IN PIO_RUN IoRuns
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);
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VOID
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UdfSingleAsync (
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IN PIRP_CONTEXT IrpContext,
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IN LONGLONG ByteOffset,
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IN ULONG ByteCount
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);
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VOID
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UdfWaitSync (
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IN PIRP_CONTEXT IrpContext
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);
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NTSTATUS
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UdfMultiSyncCompletionRoutine (
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IN PDEVICE_OBJECT DeviceObject,
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IN PIRP Irp,
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IN PVOID Context
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);
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NTSTATUS
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UdfMultiAsyncCompletionRoutine (
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IN PDEVICE_OBJECT DeviceObject,
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IN PIRP Irp,
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IN PVOID Context
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);
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NTSTATUS
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UdfSingleSyncCompletionRoutine (
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IN PDEVICE_OBJECT DeviceObject,
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IN PIRP Irp,
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IN PVOID Context
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);
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NTSTATUS
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UdfSingleAsyncCompletionRoutine (
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IN PDEVICE_OBJECT DeviceObject,
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IN PIRP Irp,
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IN PVOID Context
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);
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#ifdef ALLOC_PRAGMA
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#endif
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#ifdef ALLOC_PRAGMA
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#pragma alloc_text(PAGE, UdfCreateUserMdl)
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#pragma alloc_text(PAGE, UdfMultipleAsync)
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#pragma alloc_text(PAGE, UdfNonCachedRead)
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#pragma alloc_text(PAGE, UdfFinishBuffers)
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#pragma alloc_text(PAGE, UdfPrepareBuffers)
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#pragma alloc_text(PAGE, UdfSingleAsync)
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#pragma alloc_text(PAGE, UdfWaitSync)
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#pragma alloc_text(PAGE, UdfPerformDevIoCtrl)
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#pragma alloc_text(PAGE, UdfReadSectors)
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#endif
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NTSTATUS
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UdfNonCachedRead (
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IN PIRP_CONTEXT IrpContext,
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IN PFCB Fcb,
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IN PCCB Ccb,
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IN LONGLONG StartingOffset,
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IN ULONG ByteCount
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)
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/*++
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Routine Description:
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This routine performs the non-cached reads of sectors. This is done by
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performing the following in a loop.
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Fill in the IoRuns array for the next block of Io.
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Send the Io to the device.
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Perform any cleanup on the Io runs array.
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We will not do async Io to any request that generates non-aligned Io.
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Also we will not perform async Io if it will exceed the size of our
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IoRuns array. These should be the unusual cases but we will raise
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or return CANT_WAIT in this routine if we detect this case.
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Arguments:
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Fcb - Fcb representing the file to read.
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StartingOffset - Logical offset in the file to read from.
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ByteCount - Number of bytes to read.
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Return Value:
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NTSTATUS - Status indicating the result of the operation.
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--*/
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{
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NTSTATUS Status = STATUS_SUCCESS;
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IO_RUN IoRuns[MAX_PARALLEL_IOS];
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ULONG RunCount = 0;
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ULONG CleanupRunCount = 0;
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PVOID UserBuffer;
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ULONG UserBufferOffset = 0;
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LONGLONG CurrentOffset = StartingOffset;
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ULONG RemainingByteCount = ByteCount;
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ULONG ThisByteCount;
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BOOLEAN Unaligned;
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BOOLEAN SparseRuns;
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BOOLEAN FlushIoBuffers = FALSE;
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BOOLEAN FirstPass = TRUE;
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PAGED_CODE();
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//
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// We want to make sure the user's buffer is locked in all cases.
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//
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if (IrpContext->Irp->MdlAddress == NULL) {
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UdfCreateUserMdl( IrpContext, ByteCount, TRUE, IoWriteAccess );
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}
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//
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// Use a try-finally to perform the final cleanup.
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//
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try {
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UdfMapUserBuffer( IrpContext, &UserBuffer);
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//
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// Loop while there are more bytes to transfer.
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//
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do {
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//
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// Call prepare buffers to set up the next entries
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// in the IoRuns array. Remember if there are any
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// unaligned entries.
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//
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RtlZeroMemory( IoRuns, sizeof( IoRuns ));
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Unaligned = UdfPrepareBuffers( IrpContext,
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IrpContext->Irp,
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Fcb,
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Ccb,
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UserBuffer,
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UserBufferOffset,
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CurrentOffset,
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RemainingByteCount,
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IoRuns,
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&CleanupRunCount,
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&ThisByteCount,
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&SparseRuns );
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RunCount = CleanupRunCount;
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//
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// Quickly finish if we wound up having no IO to perform. This will
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// occur in the presence of unrecorded sectors.
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//
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ASSERT( !(SparseRuns && FlagOn( Fcb->FcbState, FCB_STATE_EMBEDDED_DATA )));
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if (RunCount == 0) {
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try_leave( Status = IrpContext->Irp->IoStatus.Status = STATUS_SUCCESS );
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}
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//
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// If this is an async request and there aren't enough entries
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// in the Io array then post the request. This routine will
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// always raise if we are doing any unaligned Io for an
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// async request.
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//
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if ((ThisByteCount < RemainingByteCount) &&
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!FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT )) {
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UdfRaiseStatus( IrpContext, STATUS_CANT_WAIT );
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}
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//
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// If the entire Io is contained in a single run then
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// we can pass the Io down to the driver. Send the driver down
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// and wait on the result if this is synchronous. We cannot
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// do this simple form (just chucking the IRP down) if some
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// sparse runs were encountered.
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//
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if ((RunCount == 1) && !Unaligned && !SparseRuns && FirstPass) {
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UdfSingleAsync( IrpContext,
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IoRuns[0].DiskOffset,
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IoRuns[0].DiskByteCount );
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//
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// No cleanup needed for the IoRuns array here.
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//
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CleanupRunCount = 0;
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//
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// Wait if we are synchronous, otherwise return
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//
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if (FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT )) {
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UdfWaitSync( IrpContext );
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Status = IrpContext->Irp->IoStatus.Status;
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//
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// Our completion routine will free the Io context but
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// we do want to return STATUS_PENDING.
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//
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} else {
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ClearFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_ALLOC_IO );
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Status = STATUS_PENDING;
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}
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try_leave( NOTHING );
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}
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//
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// Otherwise we will perform multiple Io to read in the data.
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//
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UdfMultipleAsync( IrpContext, RunCount, IoRuns );
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//
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// If this is a synchronous request then perform any necessary
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// post-processing.
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//
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if (FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT )) {
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//
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// Wait for the request to complete.
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//
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UdfWaitSync( IrpContext );
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Status = IrpContext->Irp->IoStatus.Status;
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//
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// Exit this loop if there is an error.
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//
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if (!NT_SUCCESS( Status )) {
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try_leave( NOTHING );
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}
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//
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// Perform post read operations on the IoRuns if
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// necessary.
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//
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if (Unaligned &&
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UdfFinishBuffers( IrpContext, IoRuns, RunCount, FALSE )) {
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FlushIoBuffers = TRUE;
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}
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//
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// No cleanup needed on the IoRuns now.
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//
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CleanupRunCount = 0;
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//
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// Exit this loop if there are no more bytes to transfer
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// or we have any error.
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//
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RemainingByteCount -= ThisByteCount;
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CurrentOffset += ThisByteCount;
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UserBuffer = Add2Ptr( UserBuffer, ThisByteCount, PVOID );
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UserBufferOffset += ThisByteCount;
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//
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// Otherwise this is an asynchronous request. Always return
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// STATUS_PENDING.
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//
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} else {
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ClearFlag( IrpContext->Flags, IRP_CONTEXT_FLAG_ALLOC_IO );
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CleanupRunCount = 0;
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try_leave( Status = STATUS_PENDING );
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break;
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}
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FirstPass = FALSE;
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} while (RemainingByteCount != 0);
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//
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// Flush the hardware cache if we performed any copy operations.
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//
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if (FlushIoBuffers) {
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KeFlushIoBuffers( IrpContext->Irp->MdlAddress, TRUE, FALSE );
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}
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} finally {
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DebugUnwind( "UdfNonCachedRead" );
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//
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// Perform final cleanup on the IoRuns if necessary.
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//
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if (CleanupRunCount != 0) {
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UdfFinishBuffers( IrpContext, IoRuns, CleanupRunCount, TRUE );
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}
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}
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return Status;
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}
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NTSTATUS
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UdfCreateUserMdl (
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IN PIRP_CONTEXT IrpContext,
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IN ULONG BufferLength,
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IN BOOLEAN RaiseOnError,
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IN ULONG Operation
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)
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/*++
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Routine Description:
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This routine locks the specified buffer for read access (we only write into
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the buffer). The file system requires this routine since it does not
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ask the I/O system to lock its buffers for direct I/O. This routine
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may only be called from the Fsd while still in the user context.
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This routine is only called if there is not already an Mdl.
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Arguments:
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BufferLength - Length of user buffer.
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RaiseOnError - Indicates if our caller wants this routine to raise on
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an error condition.
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Return Value:
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NTSTATUS - Status from this routine. Error status only returned if
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RaiseOnError is FALSE.
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--*/
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{
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NTSTATUS Status = STATUS_INSUFFICIENT_RESOURCES;
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PMDL Mdl;
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PAGED_CODE();
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ASSERT_IRP_CONTEXT( IrpContext );
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ASSERT_IRP( IrpContext->Irp );
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ASSERT( IrpContext->Irp->MdlAddress == NULL );
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//
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// Allocate the Mdl, and Raise if we fail.
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//
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Mdl = IoAllocateMdl( IrpContext->Irp->UserBuffer,
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BufferLength,
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FALSE,
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FALSE,
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IrpContext->Irp );
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if (Mdl != NULL) {
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//
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// Now probe the buffer described by the Irp. If we get an exception,
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// deallocate the Mdl and return the appropriate "expected" status.
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//
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try {
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MmProbeAndLockPages( Mdl, IrpContext->Irp->RequestorMode, Operation );
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Status = STATUS_SUCCESS;
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} except(EXCEPTION_EXECUTE_HANDLER) {
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Status = GetExceptionCode();
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IoFreeMdl( Mdl );
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IrpContext->Irp->MdlAddress = NULL;
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if (!FsRtlIsNtstatusExpected( Status )) {
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Status = STATUS_INVALID_USER_BUFFER;
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}
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}
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}
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|
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//
|
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// Check if we are to raise or return
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//
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if (Status != STATUS_SUCCESS) {
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if (RaiseOnError) {
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UdfRaiseStatus( IrpContext, Status );
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}
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}
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//
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// Return the status code.
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//
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return Status;
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}
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|
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NTSTATUS
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UdfPerformDevIoCtrl (
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IN PIRP_CONTEXT IrpContext,
|
|
IN ULONG IoControlCode,
|
|
IN PDEVICE_OBJECT Device,
|
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IN PVOID InputBuffer OPTIONAL,
|
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IN ULONG InputBufferLength,
|
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OUT PVOID OutputBuffer OPTIONAL,
|
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IN ULONG OutputBufferLength,
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IN BOOLEAN InternalDeviceIoControl,
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IN BOOLEAN OverrideVerify,
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OUT PIO_STATUS_BLOCK Iosb OPTIONAL
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)
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|
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/*++
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Routine Description:
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This routine is called to perform DevIoCtrl functions internally within
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the filesystem. We take the status from the driver and return it to our
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caller.
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Arguments:
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IoControlCode - Code to send to driver.
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Device - This is the device to send the request to.
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OutPutBuffer - Pointer to output buffer.
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OutputBufferLength - Length of output buffer above.
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InternalDeviceIoControl - Indicates if this is an internal or external
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Io control code.
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OverrideVerify - Indicates if we should tell the driver not to return
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STATUS_VERIFY_REQUIRED for mount and verify.
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Iosb - If specified, we return the results of the operation here.
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Return Value:
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NTSTATUS - Status returned by next lower driver.
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--*/
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|
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{
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NTSTATUS Status;
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PIRP Irp;
|
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KEVENT Event;
|
|
IO_STATUS_BLOCK LocalIosb;
|
|
PIO_STATUS_BLOCK IosbToUse = &LocalIosb;
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|
|
PAGED_CODE();
|
|
|
|
//
|
|
// Check if the user gave us an Iosb.
|
|
//
|
|
|
|
if (ARGUMENT_PRESENT( Iosb )) {
|
|
|
|
IosbToUse = Iosb;
|
|
}
|
|
|
|
IosbToUse->Status = 0;
|
|
IosbToUse->Information = 0;
|
|
|
|
KeInitializeEvent( &Event, NotificationEvent, FALSE );
|
|
|
|
Irp = IoBuildDeviceIoControlRequest( IoControlCode,
|
|
Device,
|
|
InputBuffer,
|
|
InputBufferLength,
|
|
OutputBuffer,
|
|
OutputBufferLength,
|
|
InternalDeviceIoControl,
|
|
&Event,
|
|
IosbToUse );
|
|
|
|
if (Irp == NULL) {
|
|
|
|
return STATUS_INSUFFICIENT_RESOURCES;
|
|
}
|
|
|
|
if (OverrideVerify) {
|
|
|
|
SetFlag( IoGetNextIrpStackLocation( Irp )->Flags, SL_OVERRIDE_VERIFY_VOLUME );
|
|
}
|
|
|
|
Status = IoCallDriver( Device, Irp );
|
|
|
|
//
|
|
// We check for device not ready by first checking Status
|
|
// and then if status pending was returned, the Iosb status
|
|
// value.
|
|
//
|
|
|
|
if (Status == STATUS_PENDING) {
|
|
|
|
(VOID) KeWaitForSingleObject( &Event,
|
|
Executive,
|
|
KernelMode,
|
|
FALSE,
|
|
(PLARGE_INTEGER)NULL );
|
|
|
|
Status = IosbToUse->Status;
|
|
}
|
|
|
|
ASSERT( !(OverrideVerify && (STATUS_VERIFY_REQUIRED == Status)));
|
|
|
|
return Status;
|
|
|
|
UNREFERENCED_PARAMETER( IrpContext );
|
|
}
|
|
|
|
|
|
NTSTATUS
|
|
UdfReadSectors (
|
|
IN PIRP_CONTEXT IrpContext,
|
|
IN LONGLONG StartingOffset,
|
|
IN ULONG ByteCount,
|
|
IN BOOLEAN ReturnError,
|
|
IN OUT PVOID Buffer,
|
|
IN PDEVICE_OBJECT TargetDeviceObject
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine is called to transfer sectors from the disk to a
|
|
specified buffer. It is used for mount and volume verify operations.
|
|
|
|
This routine is synchronous, it will not return until the operation
|
|
is complete or until the operation fails.
|
|
|
|
The routine allocates an IRP and then passes this IRP to a lower
|
|
level driver. Errors may occur in the allocation of this IRP or
|
|
in the operation of the lower driver.
|
|
|
|
Arguments:
|
|
|
|
StartingOffset - Logical offset on the disk to start the read. This
|
|
must be on a sector boundary, no check is made here.
|
|
|
|
ByteCount - Number of bytes to read. This is an integral number of
|
|
sectors, or otherwise a value we know the driver can handle,
|
|
no check is made here to confirm this.
|
|
|
|
ReturnError - Indicates whether we should return TRUE or FALSE
|
|
to indicate an error or raise an error condition. This only applies
|
|
to the result of the IO. Any other error may cause a raise.
|
|
|
|
Buffer - Buffer to transfer the disk data into.
|
|
|
|
TargetDeviceObject - The device object for the volume to be read.
|
|
|
|
Return Value:
|
|
|
|
The final status of the operation.
|
|
|
|
--*/
|
|
|
|
{
|
|
PLONGLONG UseStartingOffset;
|
|
LONGLONG LocalStartingOffset;
|
|
NTSTATUS Status;
|
|
KEVENT Event;
|
|
PIRP Irp;
|
|
|
|
PAGED_CODE();
|
|
|
|
DebugTrace(( +1, Dbg,
|
|
"UdfReadSectors, %x%08x +%x -> %08x from DO %08x\n",
|
|
((PLARGE_INTEGER)&StartingOffset)->HighPart,
|
|
((PLARGE_INTEGER)&StartingOffset)->LowPart,
|
|
ByteCount,
|
|
Buffer,
|
|
TargetDeviceObject ));
|
|
|
|
//
|
|
// For the time being, we assume that we only read sector-at-a-time.
|
|
// This simplifies sparing, and is the only way I am aware of this
|
|
// code would not be ready for blocksize != sectorsize. It just is
|
|
// not worth writing dead (but straightforward) code right now.
|
|
//
|
|
|
|
ASSERT( IrpContext->Vcb == NULL || ByteCount == SectorSize( IrpContext->Vcb ));
|
|
|
|
//
|
|
// If the volume is spared (and at a point where sparing is possible),
|
|
// check if a mapping needs to be performed.
|
|
//
|
|
|
|
if (IrpContext->Vcb &&
|
|
IrpContext->Vcb->Pcb &&
|
|
IrpContext->Vcb->Pcb->SparingMcb) {
|
|
|
|
LONGLONG SparingPsn;
|
|
|
|
if (FsRtlLookupLargeMcbEntry( IrpContext->Vcb->Pcb->SparingMcb,
|
|
LlSectorsFromBytes( IrpContext->Vcb, StartingOffset ),
|
|
&SparingPsn,
|
|
NULL,
|
|
NULL,
|
|
NULL,
|
|
NULL ) &&
|
|
SparingPsn != -1) {
|
|
|
|
StartingOffset = BytesFromSectors( IrpContext->Vcb, (ULONG) SparingPsn );
|
|
}
|
|
}
|
|
|
|
//
|
|
// Initialize the event.
|
|
//
|
|
|
|
KeInitializeEvent( &Event, NotificationEvent, FALSE );
|
|
|
|
//
|
|
// Correct the starting offset by the method 2 fixup if neccesary. This also
|
|
// assumes sector-at-a-time and sector == block so we don't need to fragment
|
|
// the request or check if it spans a packet boundary.
|
|
//
|
|
// We assume that no fixups are required until a Vcb exists. This is true
|
|
// since volume recognition may proceed in the first packet.
|
|
//
|
|
|
|
UseStartingOffset = &StartingOffset;
|
|
|
|
if (IrpContext->Vcb &&
|
|
FlagOn( IrpContext->Vcb->VcbState, VCB_STATE_METHOD_2_FIXUP )) {
|
|
|
|
LocalStartingOffset = UdfMethod2TransformByteOffset( IrpContext->Vcb, StartingOffset );
|
|
UseStartingOffset = &LocalStartingOffset;
|
|
|
|
DebugTrace(( 0, Dbg,
|
|
"UdfReadSectors, Method2 Fixup to %x%08x\n",
|
|
((PLARGE_INTEGER)UseStartingOffset)->HighPart,
|
|
((PLARGE_INTEGER)UseStartingOffset)->LowPart ));
|
|
}
|
|
|
|
//
|
|
// Attempt to allocate the IRP. If unsuccessful, raise
|
|
// STATUS_INSUFFICIENT_RESOURCES.
|
|
//
|
|
|
|
Irp = IoBuildSynchronousFsdRequest( IRP_MJ_READ,
|
|
TargetDeviceObject,
|
|
Buffer,
|
|
ByteCount,
|
|
(PLARGE_INTEGER) UseStartingOffset,
|
|
&Event,
|
|
&IrpContext->Irp->IoStatus );
|
|
|
|
if (Irp == NULL) {
|
|
|
|
UdfRaiseStatus( IrpContext, STATUS_INSUFFICIENT_RESOURCES );
|
|
}
|
|
|
|
//
|
|
// Ignore the change line (verify) for mount and verify requests
|
|
//
|
|
|
|
SetFlag( IoGetNextIrpStackLocation( Irp )->Flags, SL_OVERRIDE_VERIFY_VOLUME );
|
|
|
|
//
|
|
// Send the request down to the driver. If an error occurs return
|
|
// it to the caller.
|
|
//
|
|
|
|
Status = IoCallDriver( TargetDeviceObject, Irp );
|
|
|
|
//
|
|
// If the status was STATUS_PENDING then wait on the event.
|
|
//
|
|
|
|
if (Status == STATUS_PENDING) {
|
|
|
|
Status = KeWaitForSingleObject( &Event,
|
|
Executive,
|
|
KernelMode,
|
|
FALSE,
|
|
NULL );
|
|
|
|
//
|
|
// On a successful wait pull the status out of the IoStatus block.
|
|
//
|
|
|
|
if (NT_SUCCESS( Status )) {
|
|
|
|
Status = IrpContext->Irp->IoStatus.Status;
|
|
}
|
|
}
|
|
|
|
DebugTrace(( -1, Dbg, "UdfReadSectors -> %08x\n", Status ));
|
|
|
|
//
|
|
// Check whether we should raise in the error case.
|
|
//
|
|
|
|
if (!NT_SUCCESS( Status ) && !ReturnError) {
|
|
|
|
UdfNormalizeAndRaiseStatus( IrpContext, Status );
|
|
}
|
|
|
|
return Status;
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
BOOLEAN
|
|
UdfPrepareBuffers (
|
|
IN PIRP_CONTEXT IrpContext,
|
|
IN PIRP Irp,
|
|
IN PFCB Fcb,
|
|
IN PCCB Ccb,
|
|
IN PVOID UserBuffer,
|
|
IN ULONG UserBufferOffset,
|
|
IN LONGLONG StartingOffset,
|
|
IN ULONG ByteCount,
|
|
IN PIO_RUN IoRuns,
|
|
IN PULONG RunCount,
|
|
IN PULONG ThisByteCount,
|
|
IN PBOOLEAN SparseRuns
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine is the worker routine which looks up each run of an IO
|
|
request and stores an entry for it in the IoRuns array. If the run
|
|
begins on an unaligned disk boundary then we will allocate a buffer
|
|
and Mdl for the unaligned portion and put it in the IoRuns entry.
|
|
|
|
This routine will raise CANT_WAIT if an unaligned transfer is encountered
|
|
and this request can't wait.
|
|
|
|
Arguments:
|
|
|
|
Irp - Originating Irp for this request.
|
|
|
|
Fcb - This is the Fcb for this data stream. It may be a file, directory,
|
|
path table or the volume file.
|
|
|
|
UserBuffer - Current position in the user's buffer.
|
|
|
|
UserBufferOffset - Offset from the start of the original user buffer.
|
|
|
|
StartingOffset - Offset in the stream to begin the read.
|
|
|
|
ByteCount - Number of bytes to read. We will fill the IoRuns array up
|
|
to this point. We will stop early if we exceed the maximum number
|
|
of parallel Ios we support.
|
|
|
|
IoRuns - Pointer to the IoRuns array. The entire array is zeroes when
|
|
this routine is called.
|
|
|
|
RunCount - Number of entries in the IoRuns array filled here.
|
|
|
|
ThisByteCount - Number of bytes described by the IoRun entries. Will
|
|
not exceed the ByteCount passed in.
|
|
|
|
SparseRuns - Will indicate whether sparse runs were a component of the
|
|
range returned. While not part of the IoRuns, this will affect
|
|
our ability to do simple IO.
|
|
|
|
Return Value:
|
|
|
|
BOOLEAN - TRUE if one of the entries in an unaligned buffer (provided
|
|
this is synchronous). FALSE otherwise.
|
|
|
|
--*/
|
|
|
|
{
|
|
PVCB Vcb;
|
|
|
|
BOOLEAN Recorded;
|
|
|
|
BOOLEAN FoundUnaligned = FALSE;
|
|
PIO_RUN ThisIoRun = IoRuns;
|
|
|
|
//
|
|
// Following indicate where we are in the current transfer. Current
|
|
// position in the file and number of bytes yet to transfer from
|
|
// this position.
|
|
//
|
|
|
|
ULONG RemainingByteCount = ByteCount;
|
|
LONGLONG CurrentFileOffset = StartingOffset;
|
|
|
|
//
|
|
// Following indicate the state of the user's buffer. We have
|
|
// the destination of the next transfer and its offset in the
|
|
// buffer. We also have the next available position in the buffer
|
|
// available for a scratch buffer. We will align this up to a sector
|
|
// boundary.
|
|
//
|
|
|
|
PVOID CurrentUserBuffer = UserBuffer;
|
|
ULONG CurrentUserBufferOffset = UserBufferOffset;
|
|
|
|
PVOID ScratchUserBuffer = UserBuffer;
|
|
ULONG ScratchUserBufferOffset = UserBufferOffset;
|
|
|
|
//
|
|
// The following is the next contiguous bytes on the disk to
|
|
// transfer. Read from the allocation package.
|
|
//
|
|
|
|
LONGLONG DiskOffset;
|
|
ULONG CurrentByteCount;
|
|
|
|
PAGED_CODE();
|
|
|
|
Vcb = Fcb->Vcb;
|
|
|
|
//
|
|
// Initialize the RunCount, ByteCount and SparseRuns.
|
|
//
|
|
|
|
*RunCount = 0;
|
|
*ThisByteCount = 0;
|
|
*SparseRuns = FALSE;
|
|
|
|
//
|
|
// Loop while there are more bytes to process or there are
|
|
// available entries in the IoRun array.
|
|
//
|
|
|
|
while (TRUE) {
|
|
|
|
*RunCount += 1;
|
|
|
|
//
|
|
// Initialize the current position in the IoRuns array.
|
|
// Find the user's buffer for this portion of the transfer.
|
|
//
|
|
|
|
ThisIoRun->UserBuffer = CurrentUserBuffer;
|
|
|
|
//
|
|
// Find the allocation information for the current offset in the
|
|
// stream.
|
|
//
|
|
|
|
Recorded = UdfLookupAllocation( IrpContext,
|
|
Fcb,
|
|
Ccb,
|
|
CurrentFileOffset,
|
|
&DiskOffset,
|
|
&CurrentByteCount );
|
|
|
|
//
|
|
// Limit ourselves to the data requested.
|
|
//
|
|
|
|
if (CurrentByteCount > RemainingByteCount) {
|
|
|
|
CurrentByteCount = RemainingByteCount;
|
|
}
|
|
|
|
//
|
|
// Handle the case of unrecorded data first.
|
|
//
|
|
|
|
if (!Recorded) {
|
|
|
|
//
|
|
// Note that we did not consume an entry.
|
|
//
|
|
|
|
*RunCount -= 1;
|
|
|
|
//
|
|
// Immediately zero the user buffer and indicate that we found sparse
|
|
// runs to the caller.
|
|
//
|
|
|
|
RtlZeroMemory( CurrentUserBuffer, CurrentByteCount );
|
|
*SparseRuns = TRUE;
|
|
|
|
//
|
|
// Push the scratch buffer pointers forward so that we don't stomp
|
|
// on the zeroed buffer.
|
|
//
|
|
|
|
ScratchUserBuffer = Add2Ptr( CurrentUserBuffer,
|
|
CurrentByteCount,
|
|
PVOID );
|
|
|
|
ScratchUserBufferOffset += CurrentByteCount;
|
|
|
|
//
|
|
// Handle the case where this is an unaligned transfer. The
|
|
// following must all be true for this to be an aligned transfer.
|
|
//
|
|
// Disk offset on a 2048 byte boundary (Start of transfer)
|
|
//
|
|
// Byte count is a multiple of 2048 (Length of transfer)
|
|
//
|
|
// Current buffer offset is also on a 2048 byte boundary.
|
|
//
|
|
// If the ByteCount is at least one sector then do the
|
|
// unaligned transfer only for the tail. We can use the
|
|
// user's buffer for the aligned portion.
|
|
//
|
|
|
|
} else if (SectorOffset( Vcb, DiskOffset ) ||
|
|
SectorOffset( Vcb, CurrentUserBufferOffset ) ||
|
|
(SectorOffset( Vcb, CurrentByteCount ) &&
|
|
CurrentByteCount < SectorSize( Vcb ))) {
|
|
|
|
//
|
|
// If we can't wait then raise.
|
|
//
|
|
|
|
if (!FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT )) {
|
|
|
|
UdfRaiseStatus( IrpContext, STATUS_CANT_WAIT );
|
|
}
|
|
|
|
//
|
|
// Remember the offset and the number of bytes out of
|
|
// the transfer buffer to copy into the user's buffer.
|
|
// We will truncate the current read to end on a sector
|
|
// boundary.
|
|
//
|
|
|
|
ThisIoRun->TransferBufferOffset = SectorOffset( Vcb, DiskOffset );
|
|
|
|
//
|
|
// Make sure this transfer ends on a sector boundary.
|
|
//
|
|
|
|
ThisIoRun->DiskOffset = LlSectorTruncate( Vcb, DiskOffset );
|
|
|
|
//
|
|
// Check if we can use a free portion of the user's buffer.
|
|
// If we can copy the bytes to an earlier portion of the
|
|
// buffer then read into that location and slide the bytes
|
|
// up.
|
|
//
|
|
// We can use the user's buffer if:
|
|
//
|
|
// The temporary location in the buffer is before the
|
|
// final destination.
|
|
//
|
|
// There is at least one sector of data to read.
|
|
//
|
|
|
|
if ((ScratchUserBufferOffset + ThisIoRun->TransferBufferOffset < CurrentUserBufferOffset) &&
|
|
(ThisIoRun->TransferBufferOffset + CurrentByteCount >= SectorSize( Vcb ))) {
|
|
|
|
ThisIoRun->DiskByteCount = SectorTruncate( Vcb, ThisIoRun->TransferBufferOffset + CurrentByteCount );
|
|
CurrentByteCount = ThisIoRun->DiskByteCount - ThisIoRun->TransferBufferOffset;
|
|
ThisIoRun->TransferByteCount = CurrentByteCount;
|
|
|
|
//
|
|
// Point to the user's buffer and Mdl for this transfer.
|
|
//
|
|
|
|
ThisIoRun->TransferBuffer = ScratchUserBuffer;
|
|
ThisIoRun->TransferMdl = Irp->MdlAddress;
|
|
ThisIoRun->TransferVirtualAddress = Add2Ptr( Irp->UserBuffer,
|
|
ScratchUserBufferOffset,
|
|
PVOID );
|
|
|
|
ScratchUserBuffer = Add2Ptr( ScratchUserBuffer,
|
|
ThisIoRun->DiskByteCount,
|
|
PVOID );
|
|
|
|
ScratchUserBufferOffset += ThisIoRun->DiskByteCount;
|
|
|
|
//
|
|
// Otherwise we need to allocate an auxilary buffer for the next sector.
|
|
//
|
|
|
|
} else {
|
|
|
|
//
|
|
// Read up to a page containing the partial data
|
|
//
|
|
|
|
ThisIoRun->DiskByteCount = SectorAlign( Vcb, ThisIoRun->TransferBufferOffset + CurrentByteCount );
|
|
|
|
if (ThisIoRun->DiskByteCount > PAGE_SIZE) {
|
|
|
|
ThisIoRun->DiskByteCount = PAGE_SIZE;
|
|
}
|
|
|
|
if (ThisIoRun->TransferBufferOffset + CurrentByteCount > ThisIoRun->DiskByteCount) {
|
|
|
|
CurrentByteCount = ThisIoRun->DiskByteCount - ThisIoRun->TransferBufferOffset;
|
|
}
|
|
|
|
ThisIoRun->TransferByteCount = CurrentByteCount;
|
|
|
|
//
|
|
// Allocate a buffer for the non-aligned transfer.
|
|
//
|
|
|
|
ThisIoRun->TransferBuffer = FsRtlAllocatePoolWithTag( UdfNonPagedPool,
|
|
PAGE_SIZE,
|
|
TAG_IO_BUFFER );
|
|
|
|
//
|
|
// Allocate and build the Mdl to describe this buffer.
|
|
//
|
|
|
|
ThisIoRun->TransferMdl = IoAllocateMdl( ThisIoRun->TransferBuffer,
|
|
PAGE_SIZE,
|
|
FALSE,
|
|
FALSE,
|
|
NULL );
|
|
|
|
ThisIoRun->TransferVirtualAddress = ThisIoRun->TransferBuffer;
|
|
|
|
if (ThisIoRun->TransferMdl == NULL) {
|
|
|
|
IrpContext->Irp->IoStatus.Information = 0;
|
|
UdfRaiseStatus( IrpContext, STATUS_INSUFFICIENT_RESOURCES );
|
|
}
|
|
|
|
MmBuildMdlForNonPagedPool( ThisIoRun->TransferMdl );
|
|
}
|
|
|
|
//
|
|
// Remember we found an unaligned transfer.
|
|
//
|
|
|
|
FoundUnaligned = TRUE;
|
|
|
|
//
|
|
// Otherwise we use the buffer and Mdl from the original request.
|
|
//
|
|
|
|
} else {
|
|
|
|
//
|
|
// Truncate the read length to a sector-aligned value. We know
|
|
// the length must be at least one sector or we wouldn't be
|
|
// here now.
|
|
//
|
|
|
|
CurrentByteCount = SectorTruncate( Vcb, CurrentByteCount );
|
|
|
|
//
|
|
// Read these sectors from the disk.
|
|
//
|
|
|
|
ThisIoRun->DiskOffset = DiskOffset;
|
|
ThisIoRun->DiskByteCount = CurrentByteCount;
|
|
|
|
//
|
|
// Use the user's buffer and Mdl as our transfer buffer
|
|
// and Mdl.
|
|
//
|
|
|
|
ThisIoRun->TransferBuffer = CurrentUserBuffer;
|
|
ThisIoRun->TransferMdl = Irp->MdlAddress;
|
|
ThisIoRun->TransferVirtualAddress = Add2Ptr( Irp->UserBuffer,
|
|
CurrentUserBufferOffset,
|
|
PVOID );
|
|
|
|
ScratchUserBuffer = Add2Ptr( CurrentUserBuffer,
|
|
CurrentByteCount,
|
|
PVOID );
|
|
|
|
ScratchUserBufferOffset += CurrentByteCount;
|
|
}
|
|
|
|
//
|
|
// Update our position in the transfer and the RunCount and
|
|
// ByteCount for the user.
|
|
//
|
|
|
|
RemainingByteCount -= CurrentByteCount;
|
|
|
|
//
|
|
// Break out if no more positions in the IoRuns array or
|
|
// we have all of the bytes accounted for.
|
|
//
|
|
|
|
*ThisByteCount += CurrentByteCount;
|
|
|
|
if ((RemainingByteCount == 0) || (*RunCount == MAX_PARALLEL_IOS)) {
|
|
|
|
break;
|
|
}
|
|
|
|
//
|
|
// Update our pointers for the user's buffer.
|
|
//
|
|
|
|
ThisIoRun = IoRuns + *RunCount;
|
|
CurrentUserBuffer = Add2Ptr( CurrentUserBuffer, CurrentByteCount, PVOID );
|
|
CurrentUserBufferOffset += CurrentByteCount;
|
|
CurrentFileOffset += CurrentByteCount;
|
|
}
|
|
|
|
return FoundUnaligned;
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
BOOLEAN
|
|
UdfFinishBuffers (
|
|
IN PIRP_CONTEXT IrpContext,
|
|
IN PIO_RUN IoRuns,
|
|
IN ULONG RunCount,
|
|
IN BOOLEAN FinalCleanup
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine is called to perform any data transferred required for
|
|
unaligned Io or to perform the final cleanup of the IoRuns array.
|
|
|
|
In all cases this is where we will deallocate any buffer and mdl
|
|
allocated to perform the unaligned transfer. If this is not the
|
|
final cleanup then we also transfer the bytes to the user buffer
|
|
and flush the hardware cache.
|
|
|
|
We walk backwards through the run array because we may be shifting data
|
|
in the user's buffer. Typical case is where we allocated a buffer for
|
|
the first part of a read and then used the user's buffer for the
|
|
next section (but stored it at the beginning of the buffer.
|
|
|
|
Arguments:
|
|
|
|
IoRuns - Pointer to the IoRuns array.
|
|
|
|
RunCount - Number of entries in the IoRuns array filled here.
|
|
|
|
FinalCleanup - Indicates if we should be deallocating temporary buffers
|
|
(TRUE) or transferring bytes for a unaligned transfers and
|
|
deallocating the buffers (FALSE). Flush the system cache if
|
|
transferring data.
|
|
|
|
Return Value:
|
|
|
|
BOOLEAN - TRUE if this request needs the Io buffers to be flushed, FALSE otherwise.
|
|
|
|
--*/
|
|
|
|
{
|
|
BOOLEAN FlushIoBuffers = FALSE;
|
|
|
|
ULONG RemainingEntries = RunCount;
|
|
PIO_RUN ThisIoRun = &IoRuns[RunCount - 1];
|
|
|
|
PAGED_CODE();
|
|
|
|
//
|
|
// Walk through each entry in the IoRun array.
|
|
//
|
|
|
|
while (RemainingEntries != 0) {
|
|
|
|
//
|
|
// We only need to deal with the case of an unaligned transfer.
|
|
//
|
|
|
|
if (ThisIoRun->TransferByteCount != 0) {
|
|
|
|
//
|
|
// If not the final cleanup then transfer the data to the
|
|
// user's buffer and remember that we will need to flush
|
|
// the user's buffer to memory.
|
|
//
|
|
|
|
if (!FinalCleanup) {
|
|
|
|
//
|
|
// If we are shifting in the user's buffer then use
|
|
// MoveMemory.
|
|
//
|
|
|
|
if (ThisIoRun->TransferMdl == IrpContext->Irp->MdlAddress) {
|
|
|
|
RtlMoveMemory( ThisIoRun->UserBuffer,
|
|
Add2Ptr( ThisIoRun->TransferBuffer,
|
|
ThisIoRun->TransferBufferOffset,
|
|
PVOID ),
|
|
ThisIoRun->TransferByteCount );
|
|
|
|
} else {
|
|
|
|
RtlCopyMemory( ThisIoRun->UserBuffer,
|
|
Add2Ptr( ThisIoRun->TransferBuffer,
|
|
ThisIoRun->TransferBufferOffset,
|
|
PVOID ),
|
|
ThisIoRun->TransferByteCount );
|
|
}
|
|
|
|
FlushIoBuffers = TRUE;
|
|
}
|
|
|
|
//
|
|
// Free any Mdl we may have allocated. If the Mdl isn't
|
|
// present then we must have failed during the allocation
|
|
// phase.
|
|
//
|
|
|
|
if (ThisIoRun->TransferMdl != IrpContext->Irp->MdlAddress) {
|
|
|
|
if (ThisIoRun->TransferMdl != NULL) {
|
|
|
|
IoFreeMdl( ThisIoRun->TransferMdl );
|
|
}
|
|
|
|
//
|
|
// Now free any buffer we may have allocated. If the Mdl
|
|
// doesn't match the original Mdl then free the buffer.
|
|
//
|
|
|
|
if (ThisIoRun->TransferBuffer != NULL) {
|
|
|
|
UdfFreePool( &ThisIoRun->TransferBuffer );
|
|
}
|
|
}
|
|
}
|
|
|
|
//
|
|
// Now handle the case where we failed in the process
|
|
// of allocating associated Irps and Mdls.
|
|
//
|
|
|
|
if (ThisIoRun->SavedIrp != NULL) {
|
|
|
|
if (ThisIoRun->SavedIrp->MdlAddress != NULL) {
|
|
|
|
IoFreeMdl( ThisIoRun->SavedIrp->MdlAddress );
|
|
}
|
|
|
|
IoFreeIrp( ThisIoRun->SavedIrp );
|
|
}
|
|
|
|
//
|
|
// Move to the previous IoRun entry.
|
|
//
|
|
|
|
ThisIoRun -= 1;
|
|
RemainingEntries -= 1;
|
|
}
|
|
|
|
//
|
|
// If we copied any data then flush the Io buffers.
|
|
//
|
|
|
|
return FlushIoBuffers;
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
VOID
|
|
UdfMultipleAsync (
|
|
IN PIRP_CONTEXT IrpContext,
|
|
IN ULONG RunCount,
|
|
IN PIO_RUN IoRuns
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine first does the initial setup required of a Master IRP that is
|
|
going to be completed using associated IRPs. This routine should not
|
|
be used if only one async request is needed, instead the single read
|
|
async routines should be called.
|
|
|
|
A context parameter is initialized, to serve as a communications area
|
|
between here and the common completion routine.
|
|
|
|
Next this routine reads or writes one or more contiguous sectors from
|
|
a device asynchronously, and is used if there are multiple reads for a
|
|
master IRP. A completion routine is used to synchronize with the
|
|
completion of all of the I/O requests started by calls to this routine.
|
|
|
|
Also, prior to calling this routine the caller must initialize the
|
|
IoStatus field in the Context, with the correct success status and byte
|
|
count which are expected if all of the parallel transfers complete
|
|
successfully. After return this status will be unchanged if all requests
|
|
were, in fact, successful. However, if one or more errors occur, the
|
|
IoStatus will be modified to reflect the error status and byte count
|
|
from the first run (by Vbo) which encountered an error. I/O status
|
|
from all subsequent runs will not be indicated.
|
|
|
|
Arguments:
|
|
|
|
RunCount - Supplies the number of multiple async requests
|
|
that will be issued against the master irp.
|
|
|
|
IoRuns - Supplies an array containing the Offset and ByteCount for the
|
|
separate requests.
|
|
|
|
Return Value:
|
|
|
|
None.
|
|
|
|
--*/
|
|
|
|
{
|
|
PIO_COMPLETION_ROUTINE CompletionRoutine;
|
|
PIO_STACK_LOCATION IrpSp;
|
|
PMDL Mdl;
|
|
PIRP Irp;
|
|
PIRP MasterIrp;
|
|
ULONG UnwindRunCount;
|
|
|
|
PAGED_CODE();
|
|
|
|
//
|
|
// Set up things according to whether this is truely async.
|
|
//
|
|
|
|
CompletionRoutine = UdfMultiSyncCompletionRoutine;
|
|
|
|
if (!FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT )) {
|
|
|
|
CompletionRoutine = UdfMultiAsyncCompletionRoutine;
|
|
}
|
|
|
|
//
|
|
// Initialize some local variables.
|
|
//
|
|
|
|
MasterIrp = IrpContext->Irp;
|
|
|
|
//
|
|
// Itterate through the runs, doing everything that can fail.
|
|
// We let the cleanup in CdFinishBuffers clean up on error.
|
|
//
|
|
|
|
for (UnwindRunCount = 0;
|
|
UnwindRunCount < RunCount;
|
|
UnwindRunCount += 1) {
|
|
|
|
//
|
|
// Create an associated IRP, making sure there is one stack entry for
|
|
// us, as well.
|
|
//
|
|
|
|
IoRuns[UnwindRunCount].SavedIrp =
|
|
Irp = IoMakeAssociatedIrp( MasterIrp, (CCHAR)(IrpContext->Vcb->TargetDeviceObject->StackSize + 1) );
|
|
|
|
if (Irp == NULL) {
|
|
|
|
IrpContext->Irp->IoStatus.Information = 0;
|
|
UdfRaiseStatus( IrpContext, STATUS_INSUFFICIENT_RESOURCES );
|
|
}
|
|
|
|
//
|
|
// Allocate and build a partial Mdl for the request.
|
|
//
|
|
|
|
Mdl = IoAllocateMdl( IoRuns[UnwindRunCount].TransferVirtualAddress,
|
|
IoRuns[UnwindRunCount].DiskByteCount,
|
|
FALSE,
|
|
FALSE,
|
|
Irp );
|
|
|
|
if (Mdl == NULL) {
|
|
|
|
IrpContext->Irp->IoStatus.Information = 0;
|
|
UdfRaiseStatus( IrpContext, STATUS_INSUFFICIENT_RESOURCES );
|
|
}
|
|
|
|
IoBuildPartialMdl( IoRuns[UnwindRunCount].TransferMdl,
|
|
Mdl,
|
|
IoRuns[UnwindRunCount].TransferVirtualAddress,
|
|
IoRuns[UnwindRunCount].DiskByteCount );
|
|
|
|
//
|
|
// Get the first IRP stack location in the associated Irp
|
|
//
|
|
|
|
IoSetNextIrpStackLocation( Irp );
|
|
IrpSp = IoGetCurrentIrpStackLocation( Irp );
|
|
|
|
//
|
|
// Setup the Stack location to describe our read.
|
|
//
|
|
|
|
IrpSp->MajorFunction = IRP_MJ_READ;
|
|
IrpSp->Parameters.Read.Length = IoRuns[UnwindRunCount].DiskByteCount;
|
|
IrpSp->Parameters.Read.ByteOffset.QuadPart = IoRuns[UnwindRunCount].DiskOffset;
|
|
|
|
//
|
|
// Set up the completion routine address in our stack frame.
|
|
//
|
|
|
|
IoSetCompletionRoutine( Irp,
|
|
CompletionRoutine,
|
|
IrpContext->IoContext,
|
|
TRUE,
|
|
TRUE,
|
|
TRUE );
|
|
|
|
//
|
|
// Setup the next IRP stack location in the associated Irp for the disk
|
|
// driver beneath us.
|
|
//
|
|
|
|
IrpSp = IoGetNextIrpStackLocation( Irp );
|
|
|
|
//
|
|
// Setup the Stack location to do a read from the disk driver.
|
|
//
|
|
|
|
IrpSp->MajorFunction = IRP_MJ_READ;
|
|
IrpSp->Parameters.Read.Length = IoRuns[UnwindRunCount].DiskByteCount;
|
|
IrpSp->Parameters.Read.ByteOffset.QuadPart = IoRuns[UnwindRunCount].DiskOffset;
|
|
}
|
|
|
|
//
|
|
// We only need to set the associated IRP count in the master irp to
|
|
// make it a master IRP. But we set the count to one more than our
|
|
// caller requested, because we do not want the I/O system to complete
|
|
// the I/O. We also set our own count.
|
|
//
|
|
|
|
IrpContext->IoContext->IrpCount = RunCount;
|
|
IrpContext->IoContext->MasterIrp = MasterIrp;
|
|
|
|
//
|
|
// We set the count in the master Irp to 1 since typically we
|
|
// will clean up the associated irps ourselves. Setting this to one
|
|
// means completing the last associated Irp with SUCCESS (in the async
|
|
// case) will complete the master irp.
|
|
//
|
|
|
|
MasterIrp->AssociatedIrp.IrpCount = 1;
|
|
|
|
//
|
|
// Now that all the dangerous work is done, issue the Io requests
|
|
//
|
|
|
|
for (UnwindRunCount = 0;
|
|
UnwindRunCount < RunCount;
|
|
UnwindRunCount++) {
|
|
|
|
Irp = IoRuns[UnwindRunCount].SavedIrp;
|
|
IoRuns[UnwindRunCount].SavedIrp = NULL;
|
|
|
|
//
|
|
// If IoCallDriver returns an error, it has completed the Irp
|
|
// and the error will be caught by our completion routines
|
|
// and dealt with as a normal IO error.
|
|
//
|
|
|
|
(VOID) IoCallDriver( IrpContext->Vcb->TargetDeviceObject, Irp );
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
VOID
|
|
UdfSingleAsync (
|
|
IN PIRP_CONTEXT IrpContext,
|
|
IN LONGLONG ByteOffset,
|
|
IN ULONG ByteCount
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine reads one or more contiguous sectors from a device
|
|
asynchronously, and is used if there is only one read necessary to
|
|
complete the IRP. It implements the read by simply filling
|
|
in the next stack frame in the Irp, and passing it on. The transfer
|
|
occurs to the single buffer originally specified in the user request.
|
|
|
|
Arguments:
|
|
|
|
ByteOffset - Supplies the starting Logical Byte Offset to begin reading from
|
|
|
|
ByteCount - Supplies the number of bytes to read from the device
|
|
|
|
Return Value:
|
|
|
|
None.
|
|
|
|
--*/
|
|
|
|
{
|
|
PIO_STACK_LOCATION IrpSp;
|
|
PIO_COMPLETION_ROUTINE CompletionRoutine;
|
|
|
|
PAGED_CODE();
|
|
|
|
//
|
|
// Set up things according to whether this is truely async.
|
|
//
|
|
|
|
if (FlagOn( IrpContext->Flags, IRP_CONTEXT_FLAG_WAIT )) {
|
|
|
|
CompletionRoutine = UdfSingleSyncCompletionRoutine;
|
|
|
|
} else {
|
|
|
|
CompletionRoutine = UdfSingleAsyncCompletionRoutine;
|
|
}
|
|
|
|
//
|
|
// Set up the completion routine address in our stack frame.
|
|
//
|
|
|
|
IoSetCompletionRoutine( IrpContext->Irp,
|
|
CompletionRoutine,
|
|
IrpContext->IoContext,
|
|
TRUE,
|
|
TRUE,
|
|
TRUE );
|
|
|
|
//
|
|
// Setup the next IRP stack location in the associated Irp for the disk
|
|
// driver beneath us.
|
|
//
|
|
|
|
IrpSp = IoGetNextIrpStackLocation( IrpContext->Irp );
|
|
|
|
//
|
|
// Setup the Stack location to do a read from the disk driver.
|
|
//
|
|
|
|
IrpSp->MajorFunction = IrpContext->MajorFunction;
|
|
IrpSp->Parameters.Read.Length = ByteCount;
|
|
IrpSp->Parameters.Read.ByteOffset.QuadPart = ByteOffset;
|
|
|
|
//
|
|
// Issue the Io request
|
|
//
|
|
|
|
//
|
|
// If IoCallDriver returns an error, it has completed the Irp
|
|
// and the error will be caught by our completion routines
|
|
// and dealt with as a normal IO error.
|
|
//
|
|
|
|
(VOID)IoCallDriver( IrpContext->Vcb->TargetDeviceObject, IrpContext->Irp );
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
VOID
|
|
UdfWaitSync (
|
|
IN PIRP_CONTEXT IrpContext
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This routine waits for one or more previously started I/O requests
|
|
from the above routines, by simply waiting on the event.
|
|
|
|
Arguments:
|
|
|
|
Return Value:
|
|
|
|
None
|
|
|
|
--*/
|
|
|
|
{
|
|
PAGED_CODE();
|
|
|
|
KeWaitForSingleObject( &IrpContext->IoContext->SyncEvent,
|
|
Executive,
|
|
KernelMode,
|
|
FALSE,
|
|
NULL );
|
|
|
|
KeClearEvent( &IrpContext->IoContext->SyncEvent );
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
NTSTATUS
|
|
UdfMultiSyncCompletionRoutine (
|
|
IN PDEVICE_OBJECT DeviceObject,
|
|
IN PIRP Irp,
|
|
IN PVOID Context
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This is the completion routine for all synchronous reads
|
|
started via UdfMultipleAsync.
|
|
|
|
The completion routine has has the following responsibilities:
|
|
|
|
If the individual request was completed with an error, then
|
|
this completion routine must see if this is the first error
|
|
and remember the error status in the Context.
|
|
|
|
If the IrpCount goes to 1, then it sets the event in the Context
|
|
parameter to signal the caller that all of the asynch requests
|
|
are done.
|
|
|
|
Arguments:
|
|
|
|
DeviceObject - Pointer to the file system device object.
|
|
|
|
Irp - Pointer to the associated Irp which is being completed. (This
|
|
Irp will no longer be accessible after this routine returns.)
|
|
|
|
Context - The context parameter which was specified for all of
|
|
the multiple asynch I/O requests for this MasterIrp.
|
|
|
|
Return Value:
|
|
|
|
The routine returns STATUS_MORE_PROCESSING_REQUIRED so that we can
|
|
immediately complete the Master Irp without being in a race condition
|
|
with the IoCompleteRequest thread trying to decrement the IrpCount in
|
|
the Master Irp.
|
|
|
|
--*/
|
|
|
|
{
|
|
PUDF_IO_CONTEXT IoContext = Context;
|
|
|
|
//
|
|
// If we got an error (or verify required), remember it in the Irp
|
|
//
|
|
|
|
if (!NT_SUCCESS( Irp->IoStatus.Status )) {
|
|
|
|
InterlockedExchange( &IoContext->Status, Irp->IoStatus.Status );
|
|
IoContext->MasterIrp->IoStatus.Information = 0;
|
|
}
|
|
|
|
//
|
|
// We must do this here since IoCompleteRequest won't get a chance
|
|
// on this associated Irp.
|
|
//
|
|
|
|
IoFreeMdl( Irp->MdlAddress );
|
|
IoFreeIrp( Irp );
|
|
|
|
if (InterlockedDecrement( &IoContext->IrpCount ) == 0) {
|
|
|
|
//
|
|
// Update the Master Irp with any error status from the associated Irps.
|
|
//
|
|
|
|
IoContext->MasterIrp->IoStatus.Status = IoContext->Status;
|
|
KeSetEvent( &IoContext->SyncEvent, 0, FALSE );
|
|
}
|
|
|
|
UNREFERENCED_PARAMETER( DeviceObject );
|
|
|
|
return STATUS_MORE_PROCESSING_REQUIRED;
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
NTSTATUS
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UdfMultiAsyncCompletionRoutine (
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IN PDEVICE_OBJECT DeviceObject,
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IN PIRP Irp,
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IN PVOID Context
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)
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/*++
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Routine Description:
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This is the completion routine for all asynchronous reads
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started via UdfMultipleAsync.
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The completion routine has has the following responsibilities:
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If the individual request was completed with an error, then
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this completion routine must see if this is the first error
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and remember the error status in the Context.
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Arguments:
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DeviceObject - Pointer to the file system device object.
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Irp - Pointer to the associated Irp which is being completed. (This
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Irp will no longer be accessible after this routine returns.)
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|
Context - The context parameter which was specified for all of
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the multiple asynch I/O requests for this MasterIrp.
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Return Value:
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Currently always returns STATUS_SUCCESS.
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--*/
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{
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PUDF_IO_CONTEXT IoContext = Context;
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PIO_STACK_LOCATION IrpSp = IoGetCurrentIrpStackLocation( Irp );
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//
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// If we got an error (or verify required), remember it in the Irp
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//
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if (!NT_SUCCESS( Irp->IoStatus.Status )) {
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InterlockedExchange( &IoContext->Status, Irp->IoStatus.Status );
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}
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//
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// Decrement IrpCount and see if it goes to zero.
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//
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if (InterlockedDecrement( &IoContext->IrpCount ) == 0) {
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//
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// Mark the master Irp pending
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//
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IoMarkIrpPending( IoContext->MasterIrp );
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//
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// Update the Master Irp with any error status from the associated Irps.
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//
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IoContext->MasterIrp->IoStatus.Status = IoContext->Status;
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//
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// Update the information field with the correct value.
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//
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IoContext->MasterIrp->IoStatus.Information = 0;
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if (NT_SUCCESS( IoContext->MasterIrp->IoStatus.Status )) {
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IoContext->MasterIrp->IoStatus.Information = IoContext->RequestedByteCount;
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}
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//
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// Now release the resource
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//
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ExReleaseResourceForThreadLite( IoContext->Resource,
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IoContext->ResourceThreadId );
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//
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// and finally, free the context record.
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//
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UdfFreeIoContext( IoContext );
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//
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// Return success in this case.
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//
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return STATUS_SUCCESS;
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} else {
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//
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// We need to cleanup the associated Irp and its Mdl.
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//
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IoFreeMdl( Irp->MdlAddress );
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IoFreeIrp( Irp );
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return STATUS_MORE_PROCESSING_REQUIRED;
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}
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UNREFERENCED_PARAMETER( DeviceObject );
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}
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|
|
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|
//
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// Local support routine
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//
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NTSTATUS
|
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UdfSingleSyncCompletionRoutine (
|
|
IN PDEVICE_OBJECT DeviceObject,
|
|
IN PIRP Irp,
|
|
IN PVOID Context
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This is the completion routine for all reads started via UdfSingleAsync.
|
|
|
|
The completion routine has has the following responsibilities:
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|
|
|
It sets the event in the Context parameter to signal the caller
|
|
that all of the asynch requests are done.
|
|
|
|
Arguments:
|
|
|
|
DeviceObject - Pointer to the file system device object.
|
|
|
|
Irp - Pointer to the Irp for this request. (This Irp will no longer
|
|
be accessible after this routine returns.)
|
|
|
|
Context - The context parameter which was specified in the call to
|
|
UdfSingleAsynch.
|
|
|
|
Return Value:
|
|
|
|
The routine returns STATUS_MORE_PROCESSING_REQUIRED so that we can
|
|
immediately complete the Master Irp without being in a race condition
|
|
with the IoCompleteRequest thread trying to decrement the IrpCount in
|
|
the Master Irp.
|
|
|
|
--*/
|
|
|
|
{
|
|
//
|
|
// Store the correct information field into the Irp.
|
|
//
|
|
|
|
if (!NT_SUCCESS( Irp->IoStatus.Status )) {
|
|
|
|
Irp->IoStatus.Information = 0;
|
|
}
|
|
|
|
KeSetEvent( &((PUDF_IO_CONTEXT)Context)->SyncEvent, 0, FALSE );
|
|
|
|
return STATUS_MORE_PROCESSING_REQUIRED;
|
|
|
|
UNREFERENCED_PARAMETER( DeviceObject );
|
|
}
|
|
|
|
|
|
//
|
|
// Local support routine
|
|
//
|
|
|
|
NTSTATUS
|
|
UdfSingleAsyncCompletionRoutine (
|
|
IN PDEVICE_OBJECT DeviceObject,
|
|
IN PIRP Irp,
|
|
IN PVOID Context
|
|
)
|
|
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This is the completion routine for all asynchronous reads
|
|
started via UdfSingleAsynch.
|
|
|
|
Arguments:
|
|
|
|
DeviceObject - Pointer to the file system device object.
|
|
|
|
Irp - Pointer to the Irp for this request. (This Irp will no longer
|
|
be accessible after this routine returns.)
|
|
|
|
Context - The context parameter which was specified in the call to
|
|
UdfSingleAsynch.
|
|
|
|
Return Value:
|
|
|
|
Currently always returns STATUS_SUCCESS.
|
|
|
|
--*/
|
|
|
|
{
|
|
//
|
|
// Update the information field with the correct value for bytes read.
|
|
//
|
|
|
|
Irp->IoStatus.Information = 0;
|
|
|
|
if (NT_SUCCESS( Irp->IoStatus.Status )) {
|
|
|
|
Irp->IoStatus.Information = ((PUDF_IO_CONTEXT) Context)->RequestedByteCount;
|
|
}
|
|
|
|
//
|
|
// Mark the Irp pending
|
|
//
|
|
|
|
IoMarkIrpPending( Irp );
|
|
|
|
//
|
|
// Now release the resource
|
|
//
|
|
|
|
ExReleaseResourceForThreadLite( ((PUDF_IO_CONTEXT) Context)->Resource,
|
|
((PUDF_IO_CONTEXT) Context)->ResourceThreadId );
|
|
|
|
//
|
|
// and finally, free the context record.
|
|
//
|
|
|
|
UdfFreeIoContext( (PUDF_IO_CONTEXT) Context );
|
|
return STATUS_SUCCESS;
|
|
|
|
UNREFERENCED_PARAMETER( DeviceObject );
|
|
}
|
|
|