obsolete.c

This is the library for all storage drivers. It simplifies writing a storage driver by implementing

/*++

Copyright (C) Microsoft Corporation, 1991 - 1999

Module Name:

    obsolete.c

Abstract:

    THESE ARE EXPORTED CLASSPNP FUNCTIONS (and their subroutines)
    WHICH ARE NOW OBSOLETE.
    BUT WE NEED TO KEEP THEM AROUND FOR LEGACY REASONS.

Environment:

    kernel mode only

Notes:


Revision History:

--*/

#include "classp.h"
#include "debug.h"

PIRP ClassRemoveCScanList(IN PCSCAN_LIST List);
VOID ClasspInitializeCScanList(IN PCSCAN_LIST List);

#ifdef ALLOC_PRAGMA
    #pragma alloc_text(PAGE, ClassDeleteSrbLookasideList)
    #pragma alloc_text(PAGE, ClassInitializeSrbLookasideList)
#endif

typedef struct _CSCAN_LIST_ENTRY {
    LIST_ENTRY Entry;
    ULONGLONG BlockNumber;
} CSCAN_LIST_ENTRY, *PCSCAN_LIST_ENTRY;





/*
 *  ClassSplitRequest
 *
 *      This is a legacy exported function.
 *      It is called by storage miniport driver that have their own
 *      StartIo routine when the transfer size is too large for the hardware.
 *      We map it to our new read/write handler.
 */
VOID ClassSplitRequest(IN PDEVICE_OBJECT Fdo, IN PIRP Irp, IN ULONG MaximumBytes)
{
    PFUNCTIONAL_DEVICE_EXTENSION fdoExt = Fdo->DeviceExtension;
    PCLASS_PRIVATE_FDO_DATA fdoData = fdoExt->PrivateFdoData;

    if (MaximumBytes > fdoData->HwMaxXferLen) {
        DBGERR(("ClassSplitRequest - driver requesting split to size that "
                "hardware is unable to handle!\n"));
    }

    if (MaximumBytes < fdoData->HwMaxXferLen){
        DBGWARN(("ClassSplitRequest - driver requesting smaller HwMaxXferLen "
                 "than required"));
        fdoData->HwMaxXferLen = MAX(MaximumBytes, PAGE_SIZE);
    }

    ServiceTransferRequest(Fdo, Irp);
}


/*++////////////////////////////////////////////////////////////////////////////

ClassIoCompleteAssociated()

Routine Description:

    This routine executes when the port driver has completed a request.
    It looks at the SRB status in the completing SRB and if not success
    it checks for valid request sense buffer information. If valid, the
    info is used to update status with more precise message of type of
    error. This routine deallocates the SRB.  This routine is used for
    requests which were build by split request.  After it has processed
    the request it decrements the Irp count in the master Irp.  If the
    count goes to zero then the master Irp is completed.

Arguments:

    Fdo - Supplies the functional device object which represents the target.

    Irp - Supplies the Irp which has completed.

    Context - Supplies a pointer to the SRB.

Return Value:

    NT status

--*/
NTSTATUS
ClassIoCompleteAssociated(
    IN PDEVICE_OBJECT Fdo,
    IN PIRP Irp,
    IN PVOID Context
    )
{
    PFUNCTIONAL_DEVICE_EXTENSION fdoExtension = Fdo->DeviceExtension;

    PIO_STACK_LOCATION irpStack = IoGetCurrentIrpStackLocation(Irp);
    PSCSI_REQUEST_BLOCK srb = Context;

    PIRP originalIrp = Irp->AssociatedIrp.MasterIrp;
    LONG irpCount;

    NTSTATUS status;
    BOOLEAN retry;

    DBGWARN(("ClassIoCompleteAssociated is OBSOLETE !"));

    //
    // Check SRB status for success of completing request.
    //

    if (SRB_STATUS(srb->SrbStatus) != SRB_STATUS_SUCCESS) {

        ULONG retryInterval;

        DebugPrint((2,"ClassIoCompleteAssociated: IRP %p, SRB %p", Irp, srb));

        //
        // Release the queue if it is frozen.
        //

        if (srb->SrbStatus & SRB_STATUS_QUEUE_FROZEN) {
            ClassReleaseQueue(Fdo);
        }

        retry = ClassInterpretSenseInfo(
                    Fdo,
                    srb,
                    irpStack->MajorFunction,
                    irpStack->MajorFunction == IRP_MJ_DEVICE_CONTROL ?
                        irpStack->Parameters.DeviceIoControl.IoControlCode :
                        0,
                    MAXIMUM_RETRIES -
                        ((ULONG)(ULONG_PTR)irpStack->Parameters.Others.Argument4),
                    &status,
                    &retryInterval);

        //
        // If the status is verified required and the this request
        // should bypass verify required then retry the request.
        //

        if (irpStack->Flags & SL_OVERRIDE_VERIFY_VOLUME &&
            status == STATUS_VERIFY_REQUIRED) {

            status = STATUS_IO_DEVICE_ERROR;
            retry = TRUE;
        }

        if (retry && ((ULONG)(ULONG_PTR)irpStack->Parameters.Others.Argument4)--) {

            //
            // Retry request. If the class driver has supplied a StartIo,
            // call it directly for retries.
            //

            DebugPrint((1, "Retry request %p\n", Irp));

            if (PORT_ALLOCATED_SENSE(fdoExtension, srb)) {
                FREE_PORT_ALLOCATED_SENSE_BUFFER(fdoExtension, srb);
            }

            RetryRequest(Fdo, Irp, srb, TRUE, retryInterval);

            return STATUS_MORE_PROCESSING_REQUIRED;
        }

    } else {

        //
        // Set status for successful request.
        //

        status = STATUS_SUCCESS;

    } // end if (SRB_STATUS(srb->SrbStatus) ...

    //
    // Return SRB to list.
    //

    if (PORT_ALLOCATED_SENSE(fdoExtension, srb)) {
        FREE_PORT_ALLOCATED_SENSE_BUFFER(fdoExtension, srb);
    }

    ClassFreeOrReuseSrb(fdoExtension, srb);

    //
    // Set status in completing IRP.
    //

    Irp->IoStatus.Status = status;

    DebugPrint((2, "ClassIoCompleteAssociated: Partial xfer IRP %p\n", Irp));

    //
    // Get next stack location. This original request is unused
    // except to keep track of the completing partial IRPs so the
    // stack location is valid.
    //

    irpStack = IoGetNextIrpStackLocation(originalIrp);

    //
    // Update status only if error so that if any partial transfer
    // completes with error, then the original IRP will return with
    // error. If any of the asynchronous partial transfer IRPs fail,
    // with an error then the original IRP will return 0 bytes transfered.
    // This is an optimization for successful transfers.
    //

    if (!NT_SUCCESS(status)) {

        originalIrp->IoStatus.Status = status;
        originalIrp->IoStatus.Information = 0;

        //
        // Set the hard error if necessary.
        //

        if (IoIsErrorUserInduced(status)) {

            //
            // Store DeviceObject for filesystem.
            //

            IoSetHardErrorOrVerifyDevice(originalIrp, Fdo);
        }
    }

    //
    // Decrement and get the count of remaining IRPs.
    //

    irpCount = InterlockedDecrement(
                    (PLONG)&irpStack->Parameters.Others.Argument1);

    DebugPrint((2, "ClassIoCompleteAssociated: Partial IRPs left %d\n",
                irpCount));

    //
    // Ensure that the irpCount doesn't go negative.  This was happening once
    // because classpnp would get confused if it ran out of resources when
    // splitting the request.
    //

    ASSERT(irpCount >= 0);

    if (irpCount == 0) {

        //
        // All partial IRPs have completed.
        //

        DebugPrint((2,
                 "ClassIoCompleteAssociated: All partial IRPs complete %p\n",
                 originalIrp));

        if (fdoExtension->CommonExtension.DriverExtension->InitData.ClassStartIo) {

            //
            // Acquire a separate copy of the remove lock so the debugging code
            // works okay and we don't have to hold up the completion of this
            // irp until after we start the next packet(s).
            //

            KIRQL oldIrql;
            UCHAR uniqueAddress;
            ClassAcquireRemoveLock(Fdo, (PIRP)&uniqueAddress);
            ClassReleaseRemoveLock(Fdo, originalIrp);
            ClassCompleteRequest(Fdo, originalIrp, IO_DISK_INCREMENT);

            KeRaiseIrql(DISPATCH_LEVEL, &oldIrql);
            IoStartNextPacket(Fdo, FALSE);
            KeLowerIrql(oldIrql);

            ClassReleaseRemoveLock(Fdo, (PIRP)&uniqueAddress);

        } else {

            //
            // just complete this request
            //

            ClassReleaseRemoveLock(Fdo, originalIrp);
            ClassCompleteRequest(Fdo, originalIrp, IO_DISK_INCREMENT);

        }

    }

    //
    // Deallocate IRP and indicate the I/O system should not attempt any more
    // processing.
    //

    IoFreeIrp(Irp);
    return STATUS_MORE_PROCESSING_REQUIRED;

} // end ClassIoCompleteAssociated()


/*++////////////////////////////////////////////////////////////////////////////

RetryRequest()

Routine Description:

    This is a wrapper around the delayed retry DPC routine, RetryRequestDPC.
    This reinitalizes the necessary fields, queues the request, and sets
    a timer to call the DPC if someone hasn't already done so.

Arguments:

    DeviceObject - Supplies the device object associated with this request.

    Irp - Supplies the request to be retried.

    Srb - Supplies a Pointer to the SCSI request block to be retied.

    Assocaiated - Indicates this is an assocatied Irp created by split request.

    RetryInterval - How long, in seconds, before retrying the request.

Return Value:

    None

--*/
VOID
RetryRequest(
    PDEVICE_OBJECT DeviceObject,
    PIRP Irp,
    PSCSI_REQUEST_BLOCK Srb,
    BOOLEAN Associated,
    ULONG RetryInterval
    )
{
    PCOMMON_DEVICE_EXTENSION commonExtension = DeviceObject->DeviceExtension;
    PIO_STACK_LOCATION currentIrpStack = IoGetCurrentIrpStackLocation(Irp);
    PIO_STACK_LOCATION nextIrpStack = IoGetNextIrpStackLocation(Irp);
    ULONG transferByteCount;

    // This function is obsolete but is still used by some of our class drivers.
    // DBGWARN(("RetryRequest is OBSOLETE !"));

    //
    // Determine the transfer count of the request.  If this is a read or a
    // write then the transfer count is in the Irp stack.  Otherwise assume
    // the MDL contains the correct length.  If there is no MDL then the
    // transfer length must be zero.
    //

    if (currentIrpStack->MajorFunction == IRP_MJ_READ ||
        currentIrpStack->MajorFunction == IRP_MJ_WRITE) {

        transferByteCount = currentIrpStack->Parameters.Read.Length;

    } else if (Irp->MdlAddress != NULL) {

        //
        // Note this assumes that only read and write requests are spilt and
        // other request do not need to be.  If the data buffer address in
        // the MDL and the SRB don't match then transfer length is most
        // likely incorrect.
        //

        ASSERT(Srb->DataBuffer == MmGetMdlVirtualAddress(Irp->MdlAddress));
        transferByteCount = Irp->MdlAddress->ByteCount;

    } else {

        transferByteCount = 0;
    }

    //
    // this is a safety net.  this should not normally be hit, since we are
    // not guaranteed to be an fdoExtension
    //

    ASSERT(!TEST_FLAG(Srb->SrbFlags, SRB_FLAGS_FREE_SENSE_BUFFER));

    //
    // Reset byte count of transfer in SRB Extension.
    //

    Srb->DataTransferLength = transferByteCount;

    //
    // Zero SRB statuses.
    //

    Srb->SrbStatus = Srb->ScsiStatus = 0;

    //
    // If this is the last retry, then disable all the special flags.
    //

    if ( 0 == (ULONG)(ULONG_PTR)currentIrpStack->Parameters.Others.Argument4 ) {
        //
        // Set the no disconnect flag, disable synchronous data transfers and
        // disable tagged queuing. This fixes some errors.
        // NOTE: Cannot clear these flags, just add to them
        //

        SET_FLAG(Srb->SrbFlags, SRB_FLAGS_DISABLE_DISCONNECT);
        SET_FLAG(Srb->SrbFlags, SRB_FLAGS_DISABLE_SYNCH_TRANSFER);
        CLEAR_FLAG(Srb->SrbFlags, SRB_FLAGS_QUEUE_ACTION_ENABLE);

        Srb->QueueTag = SP_UNTAGGED;
    }


    //
    // Set up major SCSI function.
    //

    nextIrpStack->MajorFunction = IRP_MJ_SCSI;

    //
    // Save SRB address in next stack for port driver.
    //

    nextIrpStack->Parameters.Scsi.Srb = Srb;

    if (Associated){
        IoSetCompletionRoutine(Irp, ClassIoCompleteAssociated, Srb, TRUE, TRUE, TRUE);
    }
    else {
        IoSetCompletionRoutine(Irp, ClassIoComplete, Srb, TRUE, TRUE, TRUE);
    }

    {
        LARGE_INTEGER retry100ns;
        retry100ns.QuadPart = RetryInterval;  // seconds
        retry100ns.QuadPart *= (LONGLONG)1000 * 1000 * 10;

        ClassRetryRequest(DeviceObject, Irp, retry100ns);
    }
    return;
} // end RetryRequest()


/*++

ClassBuildRequest()

Routine Description:

    This routine allocates an SRB for the specified request then calls
    ClasspBuildRequestEx to create a SCSI operation to read or write the device.

    If no SRB is available then the request will be queued to be issued later
    when requests are available.  Drivers which do not want the queueing
    behavior should allocate the SRB themselves and call ClasspBuildRequestEx
    to issue it.

Arguments:

    Fdo - Supplies the functional device object associated with this request.

    Irp - Supplies the request to be retried.

Note:

    If the IRP is for a disk transfer, the byteoffset field
    will already have been adjusted to make it relative to
    the beginning of the disk.


Return Value:

    NT Status

--*/
NTSTATUS
ClassBuildRequest(
    PDEVICE_OBJECT Fdo,
    PIRP Irp
    )
{
    PFUNCTIONAL_DEVICE_EXTENSION fdoExtension = Fdo->DeviceExtension;

    PSCSI_REQUEST_BLOCK srb;

    // This function is obsolete, but still called by CDROM.SYS .
    // DBGWARN(("ClassBuildRequest is OBSOLETE !"));

    //
    // Allocate an Srb.
    //

    srb = ClasspAllocateSrb(fdoExtension);

    if(srb == NULL) {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    ClasspBuildRequestEx(fdoExtension, Irp, srb);
    return STATUS_SUCCESS;

} // end ClassBuildRequest()


VOID
ClasspBuildRequestEx(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension,
    IN PIRP Irp,
    IN PSCSI_REQUEST_BLOCK Srb
    )

/*++

ClasspBuildRequestEx()

Routine Description:

    This routine allocates and builds an Srb for a read or write request.
    The block address and length are supplied by the Irp. The retry count
    is stored in the current stack for use by ClassIoComplete which
    processes these requests when they complete.  The Irp is ready to be
    passed to the port driver when this routine returns.