Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1583 insertions, 0 deletions

diff --git a/src/VBox/Devices/Storage/DrvSCSI.cpp b/src/VBox/Devices/Storage/DrvSCSI.cpp
new file mode 100644
index 00000000..e2364895
--- /dev/null
+++ b/src/VBox/Devices/Storage/DrvSCSI.cpp
@@ -0,0 +1,1583 @@
+/* $Id: DrvSCSI.cpp $ */
+/** @file
+ * VBox storage drivers: Generic SCSI command parser and execution driver
+ */
+
+/*
+ * Copyright (C) 2006-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, in version 3 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+//#define DEBUG
+#define LOG_GROUP LOG_GROUP_DRV_SCSI
+#include <VBox/vmm/pdmdrv.h>
+#include <VBox/vmm/pdmifs.h>
+#include <VBox/vmm/pdmqueue.h>
+#include <VBox/vmm/pdmstorageifs.h>
+#include <VBox/vmm/pdmthread.h>
+#include <VBox/vscsi.h>
+#include <VBox/scsi.h>
+#include <iprt/asm.h>
+#include <iprt/assert.h>
+#include <iprt/mem.h>
+#include <iprt/req.h>
+#include <iprt/semaphore.h>
+#include <iprt/string.h>
+#include <iprt/uuid.h>
+
+#include "VBoxDD.h"
+
+/** The maximum number of release log entries per device. */
+#define MAX_LOG_REL_ERRORS  1024
+
+/**
+ * Eject state.
+ */
+typedef struct DRVSCSIEJECTSTATE
+{
+    /** The item core for the PDM queue. */
+    PDMQUEUEITEMCORE Core;
+    /** Event semaphore to signal when complete. */
+    RTSEMEVENT       hSemEvt;
+    /** Status of the eject operation. */
+    int              rcReq;
+} DRVSCSIEJECTSTATE;
+typedef DRVSCSIEJECTSTATE *PDRVSCSIEJECTSTATE;
+
+/**
+ * SCSI driver private per request data.
+ */
+typedef struct DRVSCSIREQ
+{
+    /** Size of the guest buffer. */
+    size_t                   cbBuf;
+    /** Temporary buffer holding the data. */
+    void                     *pvBuf;
+    /** Data segment. */
+    RTSGSEG                  Seg;
+    /** Transfer direction. */
+    PDMMEDIAEXIOREQSCSITXDIR enmXferDir;
+    /** The VSCSI request handle. */
+    VSCSIREQ                 hVScsiReq;
+    /** Where to store the SCSI status code. */
+    uint8_t                  *pu8ScsiSts;
+    /** Where to store the amount of sense data written, optional. */
+    size_t                   *pcbSense;
+    /** Where to store the transfer direction determined by the VSCSI layer, optional. */
+    PDMMEDIAEXIOREQSCSITXDIR *penmXferDir;
+    /** Transfer size determined by the VSCSI layer. */
+    size_t                   cbXfer;
+    /** Start of the request data for the device above us. */
+    uint8_t                  abAlloc[1];
+} DRVSCSIREQ;
+/** Pointer to the driver private per request data. */
+typedef DRVSCSIREQ *PDRVSCSIREQ;
+
+/**
+ * SCSI driver instance data.
+ *
+ * @implements  PDMIMEDIAEXPORT
+ * @implements  PDMIMEDIAEX
+ * @implements  PDMIMOUNTNOTIFY
+ */
+typedef struct DRVSCSI
+{
+    /** Pointer driver instance. */
+    PPDMDRVINS              pDrvIns;
+
+    /** Pointer to the attached driver's base interface. */
+    PPDMIBASE               pDrvBase;
+    /** Pointer to the attached driver's block interface. */
+    PPDMIMEDIA              pDrvMedia;
+    /** Pointer to the attached driver's extended media interface. */
+    PPDMIMEDIAEX            pDrvMediaEx;
+    /** Pointer to the attached driver's mount interface. */
+    PPDMIMOUNT              pDrvMount;
+    /** Pointer to the extended media port interface of the device above. */
+    PPDMIMEDIAEXPORT        pDevMediaExPort;
+    /** Pointer to the media port interface of the device above. */
+    PPDMIMEDIAPORT          pDevMediaPort;
+    /** pointer to the Led port interface of the dveice above. */
+    PPDMILEDPORTS           pLedPort;
+    /** The media interface for the device above. */
+    PDMIMEDIA               IMedia;
+    /** The extended media interface for the device above. */
+    PDMIMEDIAEX             IMediaEx;
+    /** The media port interface. */
+    PDMIMEDIAPORT           IPort;
+    /** The optional extended media port interface. */
+    PDMIMEDIAEXPORT         IPortEx;
+    /** The mount notify interface. */
+    PDMIMOUNTNOTIFY         IMountNotify;
+    /** Fallback status LED state for this drive.
+     * This is used in case the device doesn't has a LED interface. */
+    PDMLED                  Led;
+    /** Pointer to the status LED for this drive. */
+    PPDMLED                 pLed;
+
+    /** VSCSI device handle. */
+    VSCSIDEVICE             hVScsiDevice;
+    /** VSCSI LUN handle. */
+    VSCSILUN                hVScsiLun;
+    /** I/O callbacks. */
+    VSCSILUNIOCALLBACKS     VScsiIoCallbacks;
+
+    /** Indicates whether PDMDrvHlpAsyncNotificationCompleted should be called by
+     * any of the dummy functions. */
+    bool volatile           fDummySignal;
+    /** Current I/O depth. */
+    volatile uint32_t       StatIoDepth;
+    /** Errors printed in the release log. */
+    unsigned                cErrors;
+
+    /** Size of the I/O request to allocate. */
+    size_t                  cbIoReqAlloc;
+    /** Size of a VSCSI I/O request. */
+    size_t                  cbVScsiIoReqAlloc;
+    /** Queue to defer unmounting to EMT. */
+    PDMQUEUEHANDLE          hQueue;
+} DRVSCSI, *PDRVSCSI;
+
+/** Convert a VSCSI I/O request handle to the associated PDMIMEDIAEX I/O request. */
+#define DRVSCSI_VSCSIIOREQ_2_PDMMEDIAEXIOREQ(a_hVScsiIoReq) (*(PPDMMEDIAEXIOREQ)((uint8_t *)(a_hVScsiIoReq) - sizeof(PDMMEDIAEXIOREQ)))
+/** Convert a PDMIMEDIAEX I/O additional request memory to a VSCSI I/O request. */
+#define DRVSCSI_PDMMEDIAEXIOREQ_2_VSCSIIOREQ(a_pvIoReqAlloc) ((VSCSIIOREQ)((uint8_t *)(a_pvIoReqAlloc) + sizeof(PDMMEDIAEXIOREQ)))
+
+/**
+ * Returns whether the given status code indicates a non fatal error.
+ *
+ * @returns True if the error can be fixed by the user after the VM was suspended.
+ *          False if not and the error should be reported to the guest.
+ * @param   rc          The status code to check.
+ */
+DECLINLINE(bool) drvscsiIsRedoPossible(int rc)
+{
+    if (   rc == VERR_DISK_FULL
+        || rc == VERR_FILE_TOO_BIG
+        || rc == VERR_BROKEN_PIPE
+        || rc == VERR_NET_CONNECTION_REFUSED
+        || rc == VERR_VD_DEK_MISSING)
+        return true;
+
+    return false;
+}
+
+
+/**
+ * Converts the given VSCSI transfer direction enum to the appropriate PDM extended media interface one.
+ *
+ * @returns The PDM extended media interface transfer direction.
+ * @param   enmVScsiXferDir     The VSCSI transfer direction.
+ */
+static PDMMEDIAEXIOREQSCSITXDIR drvscsiVScsiXferDir2PdmMediaExDir(VSCSIXFERDIR enmVScsiXferDir)
+{
+    switch (enmVScsiXferDir)
+    {
+        case VSCSIXFERDIR_UNKNOWN: return PDMMEDIAEXIOREQSCSITXDIR_UNKNOWN;
+        case VSCSIXFERDIR_T2I:     return PDMMEDIAEXIOREQSCSITXDIR_FROM_DEVICE;
+        case VSCSIXFERDIR_I2T:     return PDMMEDIAEXIOREQSCSITXDIR_TO_DEVICE;
+        case VSCSIXFERDIR_NONE:    return PDMMEDIAEXIOREQSCSITXDIR_NONE;
+        default:                   return PDMMEDIAEXIOREQSCSITXDIR_INVALID;
+    }
+
+    /*return PDMMEDIAEXIOREQSCSITXDIR_INVALID;*/
+}
+
+
+/* -=-=-=-=- VScsiIoCallbacks -=-=-=-=- */
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunReqAllocSizeSet}
+ */
+static DECLCALLBACK(int) drvscsiReqAllocSizeSet(VSCSILUN hVScsiLun, void *pvScsiLunUser, size_t cbVScsiIoReqAlloc)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+
+    /* We need to store the I/O request handle so we can get it when VSCSI queues an I/O request. */
+    int rc = pThis->pDrvMediaEx->pfnIoReqAllocSizeSet(pThis->pDrvMediaEx, cbVScsiIoReqAlloc + sizeof(PDMMEDIAEXIOREQ));
+    if (RT_SUCCESS(rc))
+        pThis->cbVScsiIoReqAlloc = cbVScsiIoReqAlloc + sizeof(PDMMEDIAEXIOREQ);
+
+    return rc;
+}
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunReqAlloc}
+ */
+static DECLCALLBACK(int) drvscsiReqAlloc(VSCSILUN hVScsiLun, void *pvScsiLunUser,
+                                         uint64_t u64Tag, PVSCSIIOREQ phVScsiIoReq)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+    PDMMEDIAEXIOREQ hIoReq;
+    void *pvIoReqAlloc;
+    int rc = pThis->pDrvMediaEx->pfnIoReqAlloc(pThis->pDrvMediaEx, &hIoReq, &pvIoReqAlloc, u64Tag,
+                                               PDMIMEDIAEX_F_SUSPEND_ON_RECOVERABLE_ERR);
+    if (RT_SUCCESS(rc))
+    {
+        PPDMMEDIAEXIOREQ phIoReq = (PPDMMEDIAEXIOREQ)pvIoReqAlloc;
+
+        *phIoReq = hIoReq;
+        *phVScsiIoReq = (VSCSIIOREQ)(phIoReq + 1);
+    }
+
+    return rc;
+}
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunReqFree}
+ */
+static DECLCALLBACK(int) drvscsiReqFree(VSCSILUN hVScsiLun, void *pvScsiLunUser, VSCSIIOREQ hVScsiIoReq)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+    PDMMEDIAEXIOREQ hIoReq = DRVSCSI_VSCSIIOREQ_2_PDMMEDIAEXIOREQ(hVScsiIoReq);
+
+    return pThis->pDrvMediaEx->pfnIoReqFree(pThis->pDrvMediaEx, hIoReq);
+}
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunMediumGetRegionCount}
+ */
+static DECLCALLBACK(uint32_t) drvscsiGetRegionCount(VSCSILUN hVScsiLun, void *pvScsiLunUser)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+
+    return pThis->pDrvMedia->pfnGetRegionCount(pThis->pDrvMedia);
+}
+
+/** @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunMediumQueryRegionProperties} */
+static DECLCALLBACK(int) drvscsiQueryRegionProperties(VSCSILUN hVScsiLun, void *pvScsiLunUser,
+                                                      uint32_t uRegion, uint64_t *pu64LbaStart,
+                                                      uint64_t *pcBlocks, uint64_t *pcbBlock,
+                                                      PVDREGIONDATAFORM penmDataForm)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+
+    return pThis->pDrvMedia->pfnQueryRegionProperties(pThis->pDrvMedia, uRegion, pu64LbaStart,
+                                                      pcBlocks, pcbBlock, penmDataForm);
+}
+
+/** @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunMediumQueryRegionPropertiesForLba} */
+static DECLCALLBACK(int) drvscsiQueryRegionPropertiesForLba(VSCSILUN hVScsiLun, void *pvScsiLunUser,
+                                                            uint64_t u64LbaStart, uint32_t *puRegion,
+                                                            uint64_t *pcBlocks, uint64_t *pcbBlock,
+                                                            PVDREGIONDATAFORM penmDataForm)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+
+    return pThis->pDrvMedia->pfnQueryRegionPropertiesForLba(pThis->pDrvMedia, u64LbaStart, puRegion,
+                                                            pcBlocks, pcbBlock, penmDataForm);
+}
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunMediumSetLock}
+ */
+static DECLCALLBACK(int) drvscsiSetLock(VSCSILUN hVScsiLun, void *pvScsiLunUser, bool fLocked)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+
+    if (fLocked)
+        pThis->pDrvMount->pfnLock(pThis->pDrvMount);
+    else
+        pThis->pDrvMount->pfnUnlock(pThis->pDrvMount);
+
+    return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunMediumEject} */
+static DECLCALLBACK(int) drvscsiEject(VSCSILUN hVScsiLun, void *pvScsiLunUser)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+    int rc = VINF_SUCCESS;
+    RTSEMEVENT hSemEvt = NIL_RTSEMEVENT;
+
+    /* This must be done from EMT. */
+    rc = RTSemEventCreate(&hSemEvt);
+    if (RT_SUCCESS(rc))
+    {
+        PDRVSCSIEJECTSTATE pEjectState = (PDRVSCSIEJECTSTATE)PDMDrvHlpQueueAlloc(pThis->pDrvIns, pThis->hQueue);
+        if (pEjectState)
+        {
+            pEjectState->hSemEvt = hSemEvt;
+            PDMDrvHlpQueueInsert(pThis->pDrvIns, pThis->hQueue, &pEjectState->Core);
+
+            /* Wait for completion. */
+            rc = RTSemEventWait(pEjectState->hSemEvt, RT_INDEFINITE_WAIT);
+            if (RT_SUCCESS(rc))
+                rc = pEjectState->rcReq;
+        }
+        else
+            rc = VERR_NO_MEMORY;
+
+        RTSemEventDestroy(pEjectState->hSemEvt);
+    }
+
+    return rc;
+}
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunReqTransferEnqueue}
+ */
+static DECLCALLBACK(int) drvscsiReqTransferEnqueue(VSCSILUN hVScsiLun, void *pvScsiLunUser, VSCSIIOREQ hVScsiIoReq)
+{
+    RT_NOREF(hVScsiLun);
+    int rc = VINF_SUCCESS;
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+    PDMMEDIAEXIOREQ hIoReq = DRVSCSI_VSCSIIOREQ_2_PDMMEDIAEXIOREQ(hVScsiIoReq);
+
+    LogFlowFunc(("Enqueuing hVScsiIoReq=%#p\n", hVScsiIoReq));
+
+    VSCSIIOREQTXDIR enmTxDir = VSCSIIoReqTxDirGet(hVScsiIoReq);
+    switch (enmTxDir)
+    {
+        case VSCSIIOREQTXDIR_FLUSH:
+        {
+            rc = pThis->pDrvMediaEx->pfnIoReqFlush(pThis->pDrvMediaEx, hIoReq);
+            if (   RT_FAILURE(rc)
+                && pThis->cErrors++ < MAX_LOG_REL_ERRORS)
+                LogRel(("SCSI#%u: Flush returned rc=%Rrc\n",
+                        pThis->pDrvIns->iInstance, rc));
+            break;
+        }
+        case VSCSIIOREQTXDIR_UNMAP:
+        {
+            PCRTRANGE paRanges;
+            unsigned cRanges;
+
+            rc = VSCSIIoReqUnmapParamsGet(hVScsiIoReq, &paRanges, &cRanges);
+            AssertRC(rc);
+
+            pThis->pLed->Asserted.s.fWriting = pThis->pLed->Actual.s.fWriting = 1;
+            rc = pThis->pDrvMediaEx->pfnIoReqDiscard(pThis->pDrvMediaEx, hIoReq, cRanges);
+            if (   RT_FAILURE(rc)
+                && pThis->cErrors++ < MAX_LOG_REL_ERRORS)
+                LogRel(("SCSI#%u: Discard returned rc=%Rrc\n",
+                        pThis->pDrvIns->iInstance, rc));
+            break;
+        }
+        case VSCSIIOREQTXDIR_READ:
+        case VSCSIIOREQTXDIR_WRITE:
+        {
+            uint64_t  uOffset    = 0;
+            size_t    cbTransfer = 0;
+            size_t    cbSeg      = 0;
+            PCRTSGSEG paSeg      = NULL;
+            unsigned  cSeg       = 0;
+
+            rc = VSCSIIoReqParamsGet(hVScsiIoReq, &uOffset, &cbTransfer,
+                                     &cSeg, &cbSeg, &paSeg);
+            AssertRC(rc);
+
+            if (enmTxDir == VSCSIIOREQTXDIR_READ)
+            {
+                pThis->pLed->Asserted.s.fReading = pThis->pLed->Actual.s.fReading = 1;
+                rc = pThis->pDrvMediaEx->pfnIoReqRead(pThis->pDrvMediaEx, hIoReq, uOffset, cbTransfer);
+            }
+            else
+            {
+                pThis->pLed->Asserted.s.fWriting = pThis->pLed->Actual.s.fWriting = 1;
+                rc = pThis->pDrvMediaEx->pfnIoReqWrite(pThis->pDrvMediaEx, hIoReq, uOffset, cbTransfer);
+            }
+
+            if (   RT_FAILURE(rc)
+                && pThis->cErrors++ < MAX_LOG_REL_ERRORS)
+                LogRel(("SCSI#%u: %s at offset %llu (%u bytes left) returned rc=%Rrc\n",
+                        pThis->pDrvIns->iInstance,
+                        enmTxDir == VSCSIIOREQTXDIR_READ
+                        ? "Read"
+                        : "Write",
+                        uOffset,
+                        cbTransfer, rc));
+            break;
+        }
+        default:
+            AssertMsgFailed(("Invalid transfer direction %u\n", enmTxDir));
+    }
+
+    if (rc == VINF_SUCCESS)
+    {
+        if (enmTxDir == VSCSIIOREQTXDIR_READ)
+            pThis->pLed->Actual.s.fReading = 0;
+        else if (enmTxDir == VSCSIIOREQTXDIR_WRITE)
+            pThis->pLed->Actual.s.fWriting = 0;
+        else
+            AssertMsg(enmTxDir == VSCSIIOREQTXDIR_FLUSH, ("Invalid transfer direction %u\n", enmTxDir));
+
+        VSCSIIoReqCompleted(hVScsiIoReq, VINF_SUCCESS, false);
+        rc = VINF_SUCCESS;
+    }
+    else if (rc == VINF_PDM_MEDIAEX_IOREQ_IN_PROGRESS)
+        rc = VINF_SUCCESS;
+    else if (RT_FAILURE(rc))
+    {
+        if (enmTxDir == VSCSIIOREQTXDIR_READ)
+            pThis->pLed->Actual.s.fReading = 0;
+        else if (enmTxDir == VSCSIIOREQTXDIR_WRITE)
+            pThis->pLed->Actual.s.fWriting = 0;
+        else
+            AssertMsg(enmTxDir == VSCSIIOREQTXDIR_FLUSH, ("Invalid transfer direction %u\n", enmTxDir));
+
+        VSCSIIoReqCompleted(hVScsiIoReq, rc, drvscsiIsRedoPossible(rc));
+        rc = VINF_SUCCESS;
+    }
+    else
+        AssertMsgFailed(("Invalid return code rc=%Rrc\n", rc));
+
+    return rc;
+}
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunGetFeatureFlags}
+ */
+static DECLCALLBACK(int) drvscsiGetFeatureFlags(VSCSILUN hVScsiLun, void *pvScsiLunUser, uint64_t *pfFeatures)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+
+    *pfFeatures = 0;
+
+    uint32_t fFeatures = 0;
+    int rc = pThis->pDrvMediaEx->pfnQueryFeatures(pThis->pDrvMediaEx, &fFeatures);
+    if (RT_SUCCESS(rc) && (fFeatures & PDMIMEDIAEX_FEATURE_F_DISCARD))
+        *pfFeatures |= VSCSI_LUN_FEATURE_UNMAP;
+
+    if (   pThis->pDrvMedia
+        && pThis->pDrvMedia->pfnIsNonRotational(pThis->pDrvMedia))
+        *pfFeatures |= VSCSI_LUN_FEATURE_NON_ROTATIONAL;
+
+    if (pThis->pDrvMedia->pfnIsReadOnly(pThis->pDrvMedia))
+        *pfFeatures |= VSCSI_LUN_FEATURE_READONLY;
+
+    return VINF_SUCCESS;
+}
+
+/**
+ * @interface_method_impl{VSCSILUNIOCALLBACKS,pfnVScsiLunQueryInqStrings}
+ */
+static DECLCALLBACK(int) drvscsiQueryInqStrings(VSCSILUN hVScsiLun, void *pvScsiLunUser, const char **ppszVendorId,
+                                                const char **ppszProductId, const char **ppszProductLevel)
+{
+    RT_NOREF(hVScsiLun);
+    PDRVSCSI pThis = (PDRVSCSI)pvScsiLunUser;
+
+    if (pThis->pDevMediaPort->pfnQueryScsiInqStrings)
+        return pThis->pDevMediaPort->pfnQueryScsiInqStrings(pThis->pDevMediaPort, ppszVendorId,
+                                                            ppszProductId, ppszProductLevel);
+
+    return VERR_NOT_FOUND;
+}
+
+/* -=-=-=-=- IPortEx -=-=-=-=- */
+
+/**
+ * @interface_method_impl{PDMIMEDIAEXPORT,pfnIoReqCompleteNotify}
+ */
+static DECLCALLBACK(int) drvscsiIoReqCompleteNotify(PPDMIMEDIAEXPORT pInterface, PDMMEDIAEXIOREQ hIoReq,
+                                                    void *pvIoReqAlloc, int rcReq)
+{
+    RT_NOREF1(hIoReq);
+
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IPortEx);
+    VSCSIIOREQ hVScsiIoReq = DRVSCSI_PDMMEDIAEXIOREQ_2_VSCSIIOREQ(pvIoReqAlloc);
+    VSCSIIOREQTXDIR enmTxDir = VSCSIIoReqTxDirGet(hVScsiIoReq);
+
+    LogFlowFunc(("Request hVScsiIoReq=%#p completed\n", hVScsiIoReq));
+
+    if (enmTxDir == VSCSIIOREQTXDIR_READ)
+        pThis->pLed->Actual.s.fReading = 0;
+    else if (   enmTxDir == VSCSIIOREQTXDIR_WRITE
+             || enmTxDir == VSCSIIOREQTXDIR_UNMAP)
+        pThis->pLed->Actual.s.fWriting = 0;
+    else
+        AssertMsg(enmTxDir == VSCSIIOREQTXDIR_FLUSH, ("Invalid transfer direction %u\n", enmTxDir));
+
+    if (RT_SUCCESS(rcReq))
+        VSCSIIoReqCompleted(hVScsiIoReq, rcReq, false /* fRedoPossible */);
+    else
+    {
+        pThis->cErrors++;
+        if (pThis->cErrors < MAX_LOG_REL_ERRORS)
+        {
+            if (enmTxDir == VSCSIIOREQTXDIR_FLUSH)
+                LogRel(("SCSI#%u: Flush returned rc=%Rrc\n",
+                        pThis->pDrvIns->iInstance, rcReq));
+            else if (enmTxDir == VSCSIIOREQTXDIR_UNMAP)
+                LogRel(("SCSI#%u: Unmap returned rc=%Rrc\n",
+                        pThis->pDrvIns->iInstance, rcReq));
+            else
+            {
+                uint64_t  uOffset    = 0;
+                size_t    cbTransfer = 0;
+                size_t    cbSeg      = 0;
+                PCRTSGSEG paSeg      = NULL;
+                unsigned  cSeg       = 0;
+
+                VSCSIIoReqParamsGet(hVScsiIoReq, &uOffset, &cbTransfer,
+                                    &cSeg, &cbSeg, &paSeg);
+
+                LogRel(("SCSI#%u: %s at offset %llu (%u bytes left) returned rc=%Rrc\n",
+                        pThis->pDrvIns->iInstance,
+                        enmTxDir == VSCSIIOREQTXDIR_READ
+                        ? "Read"
+                        : "Write",
+                        uOffset,
+                        cbTransfer, rcReq));
+            }
+        }
+
+        VSCSIIoReqCompleted(hVScsiIoReq, rcReq, drvscsiIsRedoPossible(rcReq));
+    }
+
+    return VINF_SUCCESS;
+}
+
+/**
+ * @interface_method_impl{PDMIMEDIAEXPORT,pfnIoReqCopyFromBuf}
+ */
+static DECLCALLBACK(int) drvscsiIoReqCopyFromBuf(PPDMIMEDIAEXPORT pInterface, PDMMEDIAEXIOREQ hIoReq,
+                                                 void *pvIoReqAlloc, uint32_t offDst, PRTSGBUF pSgBuf,
+                                                 size_t cbCopy)
+{
+    RT_NOREF2(pInterface, hIoReq);
+
+    VSCSIIOREQ hVScsiIoReq = DRVSCSI_PDMMEDIAEXIOREQ_2_VSCSIIOREQ(pvIoReqAlloc);
+    uint64_t  uOffset    = 0;
+    size_t    cbTransfer = 0;
+    size_t    cbSeg      = 0;
+    PCRTSGSEG paSeg      = NULL;
+    unsigned  cSeg       = 0;
+    size_t    cbCopied   = 0;
+
+    int rc = VSCSIIoReqParamsGet(hVScsiIoReq, &uOffset, &cbTransfer, &cSeg, &cbSeg, &paSeg);
+    if (RT_SUCCESS(rc))
+    {
+        RTSGBUF SgBuf;
+        RTSgBufInit(&SgBuf, paSeg, cSeg);
+
+        RTSgBufAdvance(&SgBuf, offDst);
+        cbCopied = RTSgBufCopy(&SgBuf, pSgBuf, cbCopy);
+    }
+
+    return cbCopied == cbCopy ? VINF_SUCCESS : VERR_PDM_MEDIAEX_IOBUF_OVERFLOW;
+}
+
+/**
+ * @interface_method_impl{PDMIMEDIAEXPORT,pfnIoReqCopyToBuf}
+ */
+static DECLCALLBACK(int) drvscsiIoReqCopyToBuf(PPDMIMEDIAEXPORT pInterface, PDMMEDIAEXIOREQ hIoReq,
+                                               void *pvIoReqAlloc, uint32_t offSrc, PRTSGBUF pSgBuf,
+                                               size_t cbCopy)
+{
+    RT_NOREF2(pInterface, hIoReq);
+
+    VSCSIIOREQ hVScsiIoReq = DRVSCSI_PDMMEDIAEXIOREQ_2_VSCSIIOREQ(pvIoReqAlloc);
+    uint64_t  uOffset    = 0;
+    size_t    cbTransfer = 0;
+    size_t    cbSeg      = 0;
+    PCRTSGSEG paSeg      = NULL;
+    unsigned  cSeg       = 0;
+    size_t    cbCopied   = 0;
+
+    int rc = VSCSIIoReqParamsGet(hVScsiIoReq, &uOffset, &cbTransfer, &cSeg, &cbSeg, &paSeg);
+    if (RT_SUCCESS(rc))
+    {
+        RTSGBUF SgBuf;
+        RTSgBufInit(&SgBuf, paSeg, cSeg);
+
+        RTSgBufAdvance(&SgBuf, offSrc);
+        cbCopied = RTSgBufCopy(pSgBuf, &SgBuf, cbCopy);
+    }
+
+    return cbCopied == cbCopy ? VINF_SUCCESS : VERR_PDM_MEDIAEX_IOBUF_UNDERRUN;
+}
+
+/**
+ * @interface_method_impl{PDMIMEDIAEXPORT,pfnIoReqQueryDiscardRanges}
+ */
+static DECLCALLBACK(int) drvscsiIoReqQueryDiscardRanges(PPDMIMEDIAEXPORT pInterface, PDMMEDIAEXIOREQ hIoReq,
+                                                        void *pvIoReqAlloc, uint32_t idxRangeStart,
+                                                        uint32_t cRanges, PRTRANGE paRanges,
+                                                        uint32_t *pcRanges)
+{
+    RT_NOREF2(pInterface, hIoReq);
+
+    VSCSIIOREQ hVScsiIoReq = DRVSCSI_PDMMEDIAEXIOREQ_2_VSCSIIOREQ(pvIoReqAlloc);
+    PCRTRANGE paRangesVScsi;
+    unsigned cRangesVScsi;
+
+    int rc = VSCSIIoReqUnmapParamsGet(hVScsiIoReq, &paRangesVScsi, &cRangesVScsi);
+    if (RT_SUCCESS(rc))
+    {
+        uint32_t cRangesCopy = RT_MIN(cRangesVScsi - idxRangeStart, cRanges);
+        Assert(   idxRangeStart < cRangesVScsi
+               && (idxRangeStart + cRanges) <= cRangesVScsi);
+
+        memcpy(paRanges, &paRangesVScsi[idxRangeStart], cRangesCopy * sizeof(RTRANGE));
+        *pcRanges = cRangesCopy;
+    }
+    return rc;
+}
+
+/**
+ * @interface_method_impl{PDMIMEDIAEXPORT,pfnIoReqStateChanged}
+ */
+static DECLCALLBACK(void) drvscsiIoReqStateChanged(PPDMIMEDIAEXPORT pInterface, PDMMEDIAEXIOREQ hIoReq,
+                                                   void *pvIoReqAlloc, PDMMEDIAEXIOREQSTATE enmState)
+{
+    RT_NOREF2(hIoReq, pvIoReqAlloc);
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IPortEx);
+
+    switch (enmState)
+    {
+        case PDMMEDIAEXIOREQSTATE_SUSPENDED:
+        {
+            /* Make sure the request is not accounted for so the VM can suspend successfully. */
+            uint32_t cTasksActive = ASMAtomicDecU32(&pThis->StatIoDepth);
+            if (!cTasksActive && pThis->fDummySignal)
+                PDMDrvHlpAsyncNotificationCompleted(pThis->pDrvIns);
+            break;
+        }
+        case PDMMEDIAEXIOREQSTATE_ACTIVE:
+            /* Make sure the request is accounted for so the VM suspends only when the request is complete. */
+            ASMAtomicIncU32(&pThis->StatIoDepth);
+            break;
+        default:
+            AssertMsgFailed(("Invalid request state given %u\n", enmState));
+    }
+
+    pThis->pDevMediaExPort->pfnIoReqStateChanged(pThis->pDevMediaExPort, hIoReq, pvIoReqAlloc, enmState);
+}
+
+
+/* -=-=-=-=- IMedia -=-=-=-=- */
+
+/** @interface_method_impl{PDMIMEDIA,pfnGetSize} */
+static DECLCALLBACK(uint64_t) drvscsiGetSize(PPDMIMEDIA pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnGetSize(pThis->pDrvMedia);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnGetSectorSize} */
+static DECLCALLBACK(uint32_t) drvscsiGetSectorSize(PPDMIMEDIA pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnGetSectorSize(pThis->pDrvMedia);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnIsReadOnly} */
+static DECLCALLBACK(bool) drvscsiIsReadOnly(PPDMIMEDIA pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnIsReadOnly(pThis->pDrvMedia);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnIsNonRotational} */
+static DECLCALLBACK(bool) drvscsiIsNonRotational(PPDMIMEDIA pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnIsNonRotational(pThis->pDrvMedia);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnBiosGetPCHSGeometry} */
+static DECLCALLBACK(int) drvscsiBiosGetPCHSGeometry(PPDMIMEDIA pInterface,
+                                                  PPDMMEDIAGEOMETRY pPCHSGeometry)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnBiosGetPCHSGeometry(pThis->pDrvMedia, pPCHSGeometry);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnBiosSetPCHSGeometry} */
+static DECLCALLBACK(int) drvscsiBiosSetPCHSGeometry(PPDMIMEDIA pInterface,
+                                                  PCPDMMEDIAGEOMETRY pPCHSGeometry)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnBiosSetPCHSGeometry(pThis->pDrvMedia, pPCHSGeometry);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnBiosGetLCHSGeometry} */
+static DECLCALLBACK(int) drvscsiBiosGetLCHSGeometry(PPDMIMEDIA pInterface,
+                                                  PPDMMEDIAGEOMETRY pLCHSGeometry)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnBiosGetLCHSGeometry(pThis->pDrvMedia, pLCHSGeometry);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnBiosSetLCHSGeometry} */
+static DECLCALLBACK(int) drvscsiBiosSetLCHSGeometry(PPDMIMEDIA pInterface,
+                                                  PCPDMMEDIAGEOMETRY pLCHSGeometry)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnBiosSetLCHSGeometry(pThis->pDrvMedia, pLCHSGeometry);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnBiosIsVisible} */
+static DECLCALLBACK(bool) drvscsiBiosIsVisible(PPDMIMEDIA pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    return pThis->pDrvMedia->pfnBiosIsVisible(pThis->pDrvMedia);
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnGetType} */
+static DECLCALLBACK(PDMMEDIATYPE) drvscsiGetType(PPDMIMEDIA pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+    VSCSILUNTYPE enmLunType;
+    PDMMEDIATYPE enmMediaType = PDMMEDIATYPE_ERROR;
+
+    int rc = VSCSIDeviceLunQueryType(pThis->hVScsiDevice, 0, &enmLunType);
+    if (RT_SUCCESS(rc))
+    {
+        switch (enmLunType)
+        {
+            case VSCSILUNTYPE_SBC:
+                enmMediaType = PDMMEDIATYPE_HARD_DISK;
+                break;
+            case VSCSILUNTYPE_MMC:
+                enmMediaType = PDMMEDIATYPE_CDROM;
+                break;
+            default:
+                enmMediaType = PDMMEDIATYPE_ERROR;
+                break;
+        }
+    }
+
+    return enmMediaType;
+}
+
+/** @interface_method_impl{PDMIMEDIA,pfnGetUuid} */
+static DECLCALLBACK(int) drvscsiGetUuid(PPDMIMEDIA pInterface, PRTUUID pUuid)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMedia);
+
+    int rc = VINF_SUCCESS;
+    if (pThis->pDrvMedia)
+        rc = pThis->pDrvMedia->pfnGetUuid(pThis->pDrvMedia, pUuid);
+    else
+        RTUuidClear(pUuid);
+
+    return rc;
+}
+
+/* -=-=-=-=- IMediaEx -=-=-=-=- */
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnQueryFeatures} */
+static DECLCALLBACK(int) drvscsiQueryFeatures(PPDMIMEDIAEX pInterface, uint32_t *pfFeatures)
+{
+    RT_NOREF1(pInterface);
+
+    *pfFeatures = PDMIMEDIAEX_FEATURE_F_RAWSCSICMD;
+    return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnNotifySuspend} */
+static DECLCALLBACK(void) drvscsiNotifySuspend(PPDMIMEDIAEX pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMediaEx);
+
+    /** @todo Don't crash if someone screws this up...  Recreated a VISO while it
+     *        was mounted and asked the GUI to use it.  Got forced umount question.
+     *        Said yes.  Ended up here with a NULL pointer. */
+    PPDMIMEDIAEX pDrvMediaEx = pThis->pDrvMediaEx;
+    if (pDrvMediaEx)
+        pDrvMediaEx->pfnNotifySuspend(pDrvMediaEx);
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqAllocSizeSet} */
+static DECLCALLBACK(int) drvscsiIoReqAllocSizeSet(PPDMIMEDIAEX pInterface, size_t cbIoReqAlloc)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMediaEx);
+
+    pThis->cbIoReqAlloc = RT_UOFFSETOF_DYN(DRVSCSIREQ, abAlloc[cbIoReqAlloc]);
+    return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqAlloc} */
+static DECLCALLBACK(int) drvscsiIoReqAlloc(PPDMIMEDIAEX pInterface, PPDMMEDIAEXIOREQ phIoReq, void **ppvIoReqAlloc,
+                                           PDMMEDIAEXIOREQID uIoReqId, uint32_t fFlags)
+{
+    RT_NOREF2(uIoReqId, fFlags);
+
+    int rc = VINF_SUCCESS;
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMediaEx);
+    PDRVSCSIREQ pReq = (PDRVSCSIREQ)RTMemAllocZ(pThis->cbIoReqAlloc);
+    if (RT_LIKELY(pReq))
+    {
+        *phIoReq = (PDMMEDIAEXIOREQ)pReq;
+        *ppvIoReqAlloc = &pReq->abAlloc[0];
+    }
+    else
+        rc = VERR_NO_MEMORY;
+
+    return rc;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqFree} */
+static DECLCALLBACK(int) drvscsiIoReqFree(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq)
+{
+    RT_NOREF1(pInterface);
+    PDRVSCSIREQ pReq = (PDRVSCSIREQ)hIoReq;
+
+    RTMemFree(pReq);
+    return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqQueryResidual} */
+static DECLCALLBACK(int) drvscsiIoReqQueryResidual(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq, size_t *pcbResidual)
+{
+    RT_NOREF1(pInterface);
+    PDRVSCSIREQ pReq = (PDRVSCSIREQ)hIoReq;
+
+    if (pReq->cbXfer && pReq->cbXfer <= pReq->cbBuf)
+        *pcbResidual = pReq->cbBuf - pReq->cbXfer;
+    else
+        *pcbResidual = 0; /* Overflow/Underrun error or no data transfers. */
+    return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqQueryXferSize} */
+static DECLCALLBACK(int) drvscsiIoReqQueryXferSize(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq, size_t *pcbXfer)
+{
+    RT_NOREF1(pInterface);
+    PDRVSCSIREQ pReq = (PDRVSCSIREQ)hIoReq;
+
+    *pcbXfer = pReq->cbXfer;
+    return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqCancelAll} */
+static DECLCALLBACK(int) drvscsiIoReqCancelAll(PPDMIMEDIAEX pInterface)
+{
+    RT_NOREF1(pInterface);
+    return VINF_SUCCESS;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqCancel} */
+static DECLCALLBACK(int) drvscsiIoReqCancel(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQID uIoReqId)
+{
+    RT_NOREF2(pInterface, uIoReqId);
+    return VERR_PDM_MEDIAEX_IOREQID_NOT_FOUND;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqRead} */
+static DECLCALLBACK(int) drvscsiIoReqRead(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq, uint64_t off, size_t cbRead)
+{
+    RT_NOREF4(pInterface, hIoReq, off, cbRead);
+    return VERR_NOT_SUPPORTED;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqWrite} */
+static DECLCALLBACK(int) drvscsiIoReqWrite(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq, uint64_t off, size_t cbWrite)
+{
+    RT_NOREF4(pInterface, hIoReq, off, cbWrite);
+    return VERR_NOT_SUPPORTED;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqFlush} */
+static DECLCALLBACK(int) drvscsiIoReqFlush(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq)
+{
+    RT_NOREF2(pInterface, hIoReq);
+    return VERR_NOT_SUPPORTED;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqDiscard} */
+static DECLCALLBACK(int) drvscsiIoReqDiscard(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq, unsigned cRangesMax)
+{
+    RT_NOREF3(pInterface, hIoReq, cRangesMax);
+    return VERR_NOT_SUPPORTED;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqSendScsiCmd} */
+static DECLCALLBACK(int) drvscsiIoReqSendScsiCmd(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq,
+                                                 uint32_t uLun, const uint8_t *pbCdb, size_t cbCdb,
+                                                 PDMMEDIAEXIOREQSCSITXDIR enmTxDir, PDMMEDIAEXIOREQSCSITXDIR *penmTxDirRet,
+                                                 size_t cbBuf, uint8_t *pabSense, size_t cbSense, size_t *pcbSenseRet,
+                                                 uint8_t *pu8ScsiSts, uint32_t cTimeoutMillies)
+{
+    RT_NOREF1(cTimeoutMillies);
+
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMediaEx);
+    PDRVSCSIREQ pReq = (PDRVSCSIREQ)hIoReq;
+    int rc = VINF_SUCCESS;
+
+    Log(("Dump for pReq=%#p Command: %s\n", pReq, SCSICmdText(pbCdb[0])));
+    Log(("cbCdb=%u\n", cbCdb));
+    for (uint32_t i = 0; i < cbCdb; i++)
+        Log(("pbCdb[%u]=%#x\n", i, pbCdb[i]));
+    Log(("cbBuf=%zu\n", cbBuf));
+
+    pReq->enmXferDir   = enmTxDir;
+    pReq->cbBuf        = cbBuf;
+    pReq->pu8ScsiSts   = pu8ScsiSts;
+    pReq->pcbSense     = pcbSenseRet;
+    pReq->penmXferDir  = penmTxDirRet;
+
+    /* Allocate and sync buffers if a data transfer is indicated. */
+    if (cbBuf)
+    {
+        pReq->pvBuf = RTMemAlloc(cbBuf);
+        if (RT_UNLIKELY(!pReq->pvBuf))
+            rc = VERR_NO_MEMORY;
+    }
+
+    if (RT_SUCCESS(rc))
+    {
+        pReq->Seg.pvSeg = pReq->pvBuf;
+        pReq->Seg.cbSeg = cbBuf;
+
+        if (   cbBuf
+            && (   enmTxDir == PDMMEDIAEXIOREQSCSITXDIR_UNKNOWN
+                || enmTxDir == PDMMEDIAEXIOREQSCSITXDIR_TO_DEVICE))
+        {
+            RTSGBUF SgBuf;
+            RTSgBufInit(&SgBuf, &pReq->Seg, 1);
+            rc = pThis->pDevMediaExPort->pfnIoReqCopyToBuf(pThis->pDevMediaExPort, hIoReq, &pReq->abAlloc[0],
+                                                           0, &SgBuf, cbBuf);
+        }
+
+        if (RT_SUCCESS(rc))
+        {
+            rc = VSCSIDeviceReqCreate(pThis->hVScsiDevice, &pReq->hVScsiReq,
+                                      uLun, (uint8_t *)pbCdb, cbCdb, cbBuf, 1, &pReq->Seg,
+                                      pabSense, cbSense, pReq);
+            if (RT_SUCCESS(rc))
+            {
+                ASMAtomicIncU32(&pThis->StatIoDepth);
+                rc = VSCSIDeviceReqEnqueue(pThis->hVScsiDevice, pReq->hVScsiReq);
+                if (RT_SUCCESS(rc))
+                    rc = VINF_PDM_MEDIAEX_IOREQ_IN_PROGRESS;
+            }
+        }
+    }
+
+    return rc;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqGetActiveCount} */
+static DECLCALLBACK(uint32_t) drvscsiIoReqGetActiveCount(PPDMIMEDIAEX pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMediaEx);
+    return pThis->StatIoDepth;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqGetSuspendedCount} */
+static DECLCALLBACK(uint32_t) drvscsiIoReqGetSuspendedCount(PPDMIMEDIAEX pInterface)
+{
+    RT_NOREF1(pInterface);
+    return 0;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqQuerySuspendedStart} */
+static DECLCALLBACK(int) drvscsiIoReqQuerySuspendedStart(PPDMIMEDIAEX pInterface, PPDMMEDIAEXIOREQ phIoReq, void **ppvIoReqAlloc)
+{
+    RT_NOREF3(pInterface, phIoReq, ppvIoReqAlloc);
+    return VERR_NOT_IMPLEMENTED;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqQuerySuspendedNext} */
+static DECLCALLBACK(int) drvscsiIoReqQuerySuspendedNext(PPDMIMEDIAEX pInterface, PDMMEDIAEXIOREQ hIoReq,
+                                                        PPDMMEDIAEXIOREQ phIoReqNext, void **ppvIoReqAllocNext)
+{
+    RT_NOREF4(pInterface, hIoReq, phIoReqNext, ppvIoReqAllocNext);
+    return VERR_NOT_IMPLEMENTED;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqSuspendedSave} */
+static DECLCALLBACK(int) drvscsiIoReqSuspendedSave(PPDMIMEDIAEX pInterface, PSSMHANDLE pSSM, PDMMEDIAEXIOREQ hIoReq)
+{
+    RT_NOREF3(pInterface, pSSM, hIoReq);
+    return VERR_NOT_IMPLEMENTED;
+}
+
+/** @interface_method_impl{PDMIMEDIAEX,pfnIoReqSuspendedLoad} */
+static DECLCALLBACK(int) drvscsiIoReqSuspendedLoad(PPDMIMEDIAEX pInterface, PSSMHANDLE pSSM, PDMMEDIAEXIOREQ hIoReq)
+{
+    RT_NOREF3(pInterface, pSSM, hIoReq);
+    return VERR_NOT_IMPLEMENTED;
+}
+
+
+static DECLCALLBACK(void) drvscsiIoReqVScsiReqCompleted(VSCSIDEVICE hVScsiDevice, void *pVScsiDeviceUser,
+                                                        void *pVScsiReqUser, int rcScsiCode, bool fRedoPossible,
+                                                        int rcReq, size_t cbXfer, VSCSIXFERDIR enmXferDir, size_t cbSense)
+{
+    RT_NOREF2(hVScsiDevice, fRedoPossible);
+    PDRVSCSI pThis = (PDRVSCSI)pVScsiDeviceUser;
+    PDRVSCSIREQ pReq = (PDRVSCSIREQ)pVScsiReqUser;
+
+    ASMAtomicDecU32(&pThis->StatIoDepth);
+
+    /* Sync buffers. */
+    if (   RT_SUCCESS(rcReq)
+        && pReq->cbBuf
+        && (   pReq->enmXferDir == PDMMEDIAEXIOREQSCSITXDIR_UNKNOWN
+            || pReq->enmXferDir == PDMMEDIAEXIOREQSCSITXDIR_FROM_DEVICE))
+    {
+        RTSGBUF SgBuf;
+        RTSgBufInit(&SgBuf, &pReq->Seg, 1);
+        int rcCopy = pThis->pDevMediaExPort->pfnIoReqCopyFromBuf(pThis->pDevMediaExPort, (PDMMEDIAEXIOREQ)pReq,
+                                                                 &pReq->abAlloc[0], 0, &SgBuf, pReq->cbBuf);
+        if (RT_FAILURE(rcCopy))
+            rcReq = rcCopy;
+    }
+
+    if (pReq->pvBuf)
+    {
+        RTMemFree(pReq->pvBuf);
+        pReq->pvBuf = NULL;
+    }
+
+    *pReq->pu8ScsiSts = (uint8_t)rcScsiCode;
+    pReq->cbXfer      = cbXfer;
+    if (pReq->pcbSense)
+        *pReq->pcbSense = cbSense;
+    if (pReq->penmXferDir)
+        *pReq->penmXferDir = drvscsiVScsiXferDir2PdmMediaExDir(enmXferDir);
+    int rc = pThis->pDevMediaExPort->pfnIoReqCompleteNotify(pThis->pDevMediaExPort, (PDMMEDIAEXIOREQ)pReq,
+                                                            &pReq->abAlloc[0], rcReq);
+    AssertRC(rc); RT_NOREF(rc);
+
+    if (RT_UNLIKELY(pThis->fDummySignal) && !pThis->StatIoDepth)
+        PDMDrvHlpAsyncNotificationCompleted(pThis->pDrvIns);
+}
+
+/**
+ * Consumer for the queue
+ *
+ * @returns Success indicator.
+ *          If false the item will not be removed and the flushing will stop.
+ * @param   pDrvIns     The driver instance.
+ * @param   pItem       The item to consume. Upon return this item will be freed.
+ * @thread  EMT
+ *
+ * @todo    r=bird: Seems the idea here is that we have to do this on an EMT,
+ *          probably because of PDMIMOUNT::pfnUnmount.  I don't quite get why
+ *          though, as EMT doesn't exactly serialize anything anymore (SMP)...
+ */
+static DECLCALLBACK(bool) drvscsiR3NotifyQueueConsumer(PPDMDRVINS pDrvIns, PPDMQUEUEITEMCORE pItem)
+{
+    PDRVSCSIEJECTSTATE pEjectState = (PDRVSCSIEJECTSTATE)pItem;
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+
+    int rc = pThis->pDrvMount->pfnUnmount(pThis->pDrvMount, false /*fForce*/, true /*fEject*/);
+    Assert(RT_SUCCESS(rc) || rc == VERR_PDM_MEDIA_LOCKED || rc == VERR_PDM_MEDIA_NOT_MOUNTED);
+    if (RT_SUCCESS(rc))
+        pThis->pDevMediaExPort->pfnMediumEjected(pThis->pDevMediaExPort);
+
+    pEjectState->rcReq = rc;
+    RTSemEventSignal(pEjectState->hSemEvt);
+    return true;
+}
+
+/* -=-=-=-=- IBase -=-=-=-=- */
+
+/**
+ * @interface_method_impl{PDMIBASE,pfnQueryInterface}
+ */
+static DECLCALLBACK(void *)  drvscsiQueryInterface(PPDMIBASE pInterface, const char *pszIID)
+{
+    PPDMDRVINS  pDrvIns = PDMIBASE_2_PDMDRV(pInterface);
+    PDRVSCSI    pThis   = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+
+    PDMIBASE_RETURN_INTERFACE(pszIID, PDMIMOUNT, pThis->pDrvMount);
+    PDMIBASE_RETURN_INTERFACE(pszIID, PDMIBASE, &pDrvIns->IBase);
+    PDMIBASE_RETURN_INTERFACE(pszIID, PDMIMEDIAEX, pThis->pDevMediaExPort ? &pThis->IMediaEx : NULL);
+    PDMIBASE_RETURN_INTERFACE(pszIID, PDMIMEDIA, pThis->pDrvMedia ? &pThis->IMedia : NULL);
+    PDMIBASE_RETURN_INTERFACE(pszIID, PDMIMEDIAPORT, &pThis->IPort);
+    PDMIBASE_RETURN_INTERFACE(pszIID, PDMIMOUNTNOTIFY, &pThis->IMountNotify);
+    PDMIBASE_RETURN_INTERFACE(pszIID, PDMIMEDIAEXPORT, &pThis->IPortEx);
+    return NULL;
+}
+
+static DECLCALLBACK(int) drvscsiQueryDeviceLocation(PPDMIMEDIAPORT pInterface, const char **ppcszController,
+                                                    uint32_t *piInstance, uint32_t *piLUN)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IPort);
+
+    return pThis->pDevMediaPort->pfnQueryDeviceLocation(pThis->pDevMediaPort, ppcszController,
+                                                        piInstance, piLUN);
+}
+
+/**
+ * Called when media is mounted.
+ *
+ * @param   pInterface      Pointer to the interface structure containing the called function pointer.
+ */
+static DECLCALLBACK(void) drvscsiMountNotify(PPDMIMOUNTNOTIFY pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMountNotify);
+    LogFlowFunc(("mounting LUN#%p\n", pThis->hVScsiLun));
+
+    /* Ignore the call if we're called while being attached. */
+    if (!pThis->pDrvMedia)
+        return;
+
+    /* Let the LUN know that a medium was mounted. */
+    VSCSILunMountNotify(pThis->hVScsiLun);
+}
+
+/**
+ * Called when media is unmounted
+ *
+ * @param   pInterface      Pointer to the interface structure containing the called function pointer.
+ */
+static DECLCALLBACK(void) drvscsiUnmountNotify(PPDMIMOUNTNOTIFY pInterface)
+{
+    PDRVSCSI pThis = RT_FROM_MEMBER(pInterface, DRVSCSI, IMountNotify);
+    LogFlowFunc(("unmounting LUN#%p\n", pThis->hVScsiLun));
+
+    /* Let the LUN know that the medium was unmounted. */
+    VSCSILunUnmountNotify(pThis->hVScsiLun);
+}
+
+/**
+ * Worker for drvscsiReset, drvscsiSuspend and drvscsiPowerOff.
+ *
+ * @param   pDrvIns         The driver instance.
+ * @param   pfnAsyncNotify  The async callback.
+ */
+static void drvscsiR3ResetOrSuspendOrPowerOff(PPDMDRVINS pDrvIns, PFNPDMDRVASYNCNOTIFY pfnAsyncNotify)
+{
+    RT_NOREF1(pfnAsyncNotify);
+
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+
+    if (pThis->StatIoDepth > 0)
+        ASMAtomicWriteBool(&pThis->fDummySignal, true);
+}
+
+/**
+ * Callback employed by drvscsiSuspend and drvscsiPowerOff.
+ *
+ * @returns true if we've quiesced, false if we're still working.
+ * @param   pDrvIns     The driver instance.
+ */
+static DECLCALLBACK(bool) drvscsiIsAsyncSuspendOrPowerOffDone(PPDMDRVINS pDrvIns)
+{
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+
+    if (pThis->StatIoDepth > 0)
+        return false;
+    else
+        return true;
+}
+
+/**
+ * @copydoc FNPDMDRVPOWEROFF
+ */
+static DECLCALLBACK(void) drvscsiPowerOff(PPDMDRVINS pDrvIns)
+{
+    drvscsiR3ResetOrSuspendOrPowerOff(pDrvIns, drvscsiIsAsyncSuspendOrPowerOffDone);
+}
+
+/**
+ * @copydoc FNPDMDRVSUSPEND
+ */
+static DECLCALLBACK(void) drvscsiSuspend(PPDMDRVINS pDrvIns)
+{
+    drvscsiR3ResetOrSuspendOrPowerOff(pDrvIns, drvscsiIsAsyncSuspendOrPowerOffDone);
+}
+
+/**
+ * Callback employed by drvscsiReset.
+ *
+ * @returns true if we've quiesced, false if we're still working.
+ * @param   pDrvIns     The driver instance.
+ */
+static DECLCALLBACK(bool) drvscsiIsAsyncResetDone(PPDMDRVINS pDrvIns)
+{
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+
+    if (pThis->StatIoDepth > 0)
+        return false;
+    else
+        return true;
+}
+
+/** @copydoc FNPDMDRVATTACH */
+static DECLCALLBACK(int) drvscsiAttach(PPDMDRVINS pDrvIns, uint32_t fFlags)
+{
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+
+    LogFlowFunc(("pDrvIns=%#p fFlags=%#x\n", pDrvIns, fFlags));
+
+    AssertMsgReturn((fFlags & PDM_TACH_FLAGS_NOT_HOT_PLUG),
+                    ("SCSI: Hotplugging is not supported\n"),
+                    VERR_INVALID_PARAMETER);
+
+    /*
+     * Try attach driver below and query it's media interface.
+     */
+    int rc = PDMDrvHlpAttach(pDrvIns, fFlags, &pThis->pDrvBase);
+    AssertMsgReturn(RT_SUCCESS(rc), ("Attaching driver below failed rc=%Rrc\n", rc), rc);
+
+    /*
+     * Query the media interface.
+     */
+    pThis->pDrvMedia = PDMIBASE_QUERY_INTERFACE(pThis->pDrvBase, PDMIMEDIA);
+    AssertMsgReturn(RT_VALID_PTR(pThis->pDrvMedia), ("VSCSI configuration error: No media interface!\n"),
+                    VERR_PDM_MISSING_INTERFACE);
+
+    /* Query the extended media interface. */
+    pThis->pDrvMediaEx = PDMIBASE_QUERY_INTERFACE(pThis->pDrvBase, PDMIMEDIAEX);
+    AssertMsgReturn(RT_VALID_PTR(pThis->pDrvMediaEx), ("VSCSI configuration error: No extended media interface!\n"),
+                    VERR_PDM_MISSING_INTERFACE);
+
+    pThis->pDrvMount = PDMIBASE_QUERY_INTERFACE(pThis->pDrvBase, PDMIMOUNT);
+
+    if (pThis->cbVScsiIoReqAlloc)
+    {
+        rc = pThis->pDrvMediaEx->pfnIoReqAllocSizeSet(pThis->pDrvMediaEx, pThis->cbVScsiIoReqAlloc);
+        AssertMsgReturn(RT_SUCCESS(rc), ("Setting the I/O request allocation size failed with rc=%Rrc\n", rc), rc);
+    }
+
+    if (pThis->pDrvMount)
+    {
+        if (pThis->pDrvMount->pfnIsMounted(pThis->pDrvMount))
+        {
+            rc = VINF_SUCCESS; VSCSILunMountNotify(pThis->hVScsiLun);
+            AssertMsgReturn(RT_SUCCESS(rc), ("Failed to notify the LUN of media being mounted\n"), rc);
+        }
+        else
+        {
+            rc = VINF_SUCCESS; VSCSILunUnmountNotify(pThis->hVScsiLun);
+            AssertMsgReturn(RT_SUCCESS(rc), ("Failed to notify the LUN of media being unmounted\n"), rc);
+        }
+    }
+
+    return rc;
+}
+
+/** @copydoc FNPDMDRVDETACH */
+static DECLCALLBACK(void) drvscsiDetach(PPDMDRVINS pDrvIns, uint32_t fFlags)
+{
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+
+    RT_NOREF(fFlags);
+    LogFlowFunc(("pDrvIns=%#p fFlags=%#x\n", pDrvIns, fFlags));
+
+    /*
+     * Zero some important members.
+     */
+    pThis->pDrvBase = NULL;
+    pThis->pDrvMedia = NULL;
+    pThis->pDrvMediaEx = NULL;
+    pThis->pDrvMount = NULL;
+
+    VSCSILunUnmountNotify(pThis->hVScsiLun);
+}
+
+/**
+ * @copydoc FNPDMDRVRESET
+ */
+static DECLCALLBACK(void) drvscsiReset(PPDMDRVINS pDrvIns)
+{
+    drvscsiR3ResetOrSuspendOrPowerOff(pDrvIns, drvscsiIsAsyncResetDone);
+}
+
+/**
+ * Destruct a driver instance.
+ *
+ * Most VM resources are freed by the VM. This callback is provided so that any non-VM
+ * resources can be freed correctly.
+ *
+ * @param   pDrvIns     The driver instance data.
+ */
+static DECLCALLBACK(void) drvscsiDestruct(PPDMDRVINS pDrvIns)
+{
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+    PDMDRV_CHECK_VERSIONS_RETURN_VOID(pDrvIns);
+
+    /* Free the VSCSI device and LUN handle. */
+    if (pThis->hVScsiDevice)
+    {
+        VSCSILUN hVScsiLun;
+        int rc = VSCSIDeviceLunDetach(pThis->hVScsiDevice, 0, &hVScsiLun);
+        AssertRC(rc);
+
+        Assert(hVScsiLun == pThis->hVScsiLun);
+        rc = VSCSILunDestroy(hVScsiLun);
+        AssertRC(rc);
+        rc = VSCSIDeviceDestroy(pThis->hVScsiDevice);
+        AssertRC(rc);
+
+        pThis->hVScsiDevice = NULL;
+        pThis->hVScsiLun    = NULL;
+    }
+}
+
+/**
+ * Construct a block driver instance.
+ *
+ * @copydoc FNPDMDRVCONSTRUCT
+ */
+static DECLCALLBACK(int) drvscsiConstruct(PPDMDRVINS pDrvIns, PCFGMNODE pCfg, uint32_t fFlags)
+{
+    RT_NOREF(pCfg);
+    PDMDRV_CHECK_VERSIONS_RETURN(pDrvIns);
+    PDRVSCSI pThis = PDMINS_2_DATA(pDrvIns, PDRVSCSI);
+    LogFlowFunc(("pDrvIns=%#p pCfg=%#p\n", pDrvIns, pCfg));
+
+    /*
+     * Initialize the instance data.
+     */
+    pThis->pDrvIns                              = pDrvIns;
+
+    pDrvIns->IBase.pfnQueryInterface            = drvscsiQueryInterface;
+
+    /* IMedia */
+    pThis->IMedia.pfnRead                       = NULL;
+    pThis->IMedia.pfnReadPcBios                 = NULL;
+    pThis->IMedia.pfnWrite                      = NULL;
+    pThis->IMedia.pfnFlush                      = NULL;
+    pThis->IMedia.pfnSendCmd                    = NULL;
+    pThis->IMedia.pfnMerge                      = NULL;
+    pThis->IMedia.pfnSetSecKeyIf                = NULL;
+    pThis->IMedia.pfnGetSize                    = drvscsiGetSize;
+    pThis->IMedia.pfnGetSectorSize              = drvscsiGetSectorSize;
+    pThis->IMedia.pfnIsReadOnly                 = drvscsiIsReadOnly;
+    pThis->IMedia.pfnIsNonRotational            = drvscsiIsNonRotational;
+    pThis->IMedia.pfnBiosGetPCHSGeometry        = drvscsiBiosGetPCHSGeometry;
+    pThis->IMedia.pfnBiosSetPCHSGeometry        = drvscsiBiosSetPCHSGeometry;
+    pThis->IMedia.pfnBiosGetLCHSGeometry        = drvscsiBiosGetLCHSGeometry;
+    pThis->IMedia.pfnBiosSetLCHSGeometry        = drvscsiBiosSetLCHSGeometry;
+    pThis->IMedia.pfnBiosIsVisible              = drvscsiBiosIsVisible;
+    pThis->IMedia.pfnGetType                    = drvscsiGetType;
+    pThis->IMedia.pfnGetUuid                    = drvscsiGetUuid;
+    pThis->IMedia.pfnDiscard                    = NULL;
+
+    /* IMediaEx */
+    pThis->IMediaEx.pfnQueryFeatures            = drvscsiQueryFeatures;
+    pThis->IMediaEx.pfnNotifySuspend            = drvscsiNotifySuspend;
+    pThis->IMediaEx.pfnIoReqAllocSizeSet        = drvscsiIoReqAllocSizeSet;
+    pThis->IMediaEx.pfnIoReqAlloc               = drvscsiIoReqAlloc;
+    pThis->IMediaEx.pfnIoReqFree                = drvscsiIoReqFree;
+    pThis->IMediaEx.pfnIoReqQueryResidual       = drvscsiIoReqQueryResidual;
+    pThis->IMediaEx.pfnIoReqQueryXferSize       = drvscsiIoReqQueryXferSize;
+    pThis->IMediaEx.pfnIoReqCancelAll           = drvscsiIoReqCancelAll;
+    pThis->IMediaEx.pfnIoReqCancel              = drvscsiIoReqCancel;
+    pThis->IMediaEx.pfnIoReqRead                = drvscsiIoReqRead;
+    pThis->IMediaEx.pfnIoReqWrite               = drvscsiIoReqWrite;
+    pThis->IMediaEx.pfnIoReqFlush               = drvscsiIoReqFlush;
+    pThis->IMediaEx.pfnIoReqDiscard             = drvscsiIoReqDiscard;
+    pThis->IMediaEx.pfnIoReqSendScsiCmd         = drvscsiIoReqSendScsiCmd;
+    pThis->IMediaEx.pfnIoReqGetActiveCount      = drvscsiIoReqGetActiveCount;
+    pThis->IMediaEx.pfnIoReqGetSuspendedCount   = drvscsiIoReqGetSuspendedCount;
+    pThis->IMediaEx.pfnIoReqQuerySuspendedStart = drvscsiIoReqQuerySuspendedStart;
+    pThis->IMediaEx.pfnIoReqQuerySuspendedNext  = drvscsiIoReqQuerySuspendedNext;
+    pThis->IMediaEx.pfnIoReqSuspendedSave       = drvscsiIoReqSuspendedSave;
+    pThis->IMediaEx.pfnIoReqSuspendedLoad       = drvscsiIoReqSuspendedLoad;
+
+    pThis->IMountNotify.pfnMountNotify          = drvscsiMountNotify;
+    pThis->IMountNotify.pfnUnmountNotify        = drvscsiUnmountNotify;
+    pThis->IPort.pfnQueryDeviceLocation         = drvscsiQueryDeviceLocation;
+    pThis->IPortEx.pfnIoReqCompleteNotify       = drvscsiIoReqCompleteNotify;
+    pThis->IPortEx.pfnIoReqCopyFromBuf          = drvscsiIoReqCopyFromBuf;
+    pThis->IPortEx.pfnIoReqCopyToBuf            = drvscsiIoReqCopyToBuf;
+    pThis->IPortEx.pfnIoReqQueryBuf             = NULL;
+    pThis->IPortEx.pfnIoReqQueryDiscardRanges   = drvscsiIoReqQueryDiscardRanges;
+    pThis->IPortEx.pfnIoReqStateChanged         = drvscsiIoReqStateChanged;
+
+    /* Query the optional media port interface above. */
+    pThis->pDevMediaPort = PDMIBASE_QUERY_INTERFACE(pDrvIns->pUpBase, PDMIMEDIAPORT);
+
+    /* Query the optional extended media port interface above. */
+    pThis->pDevMediaExPort = PDMIBASE_QUERY_INTERFACE(pDrvIns->pUpBase, PDMIMEDIAEXPORT);
+
+    AssertMsgReturn(pThis->pDevMediaExPort,
+                    ("Missing extended media port interface above\n"), VERR_PDM_MISSING_INTERFACE);
+
+    /* Query the optional LED interface above. */
+    pThis->pLedPort = PDMIBASE_QUERY_INTERFACE(pDrvIns->pUpBase, PDMILEDPORTS);
+    if (pThis->pLedPort != NULL)
+    {
+        /* Get The Led. */
+        int rc = pThis->pLedPort->pfnQueryStatusLed(pThis->pLedPort, 0, &pThis->pLed);
+        if (RT_FAILURE(rc))
+            pThis->pLed = &pThis->Led;
+    }
+    else
+        pThis->pLed = &pThis->Led;
+
+    /*
+     * Validate and read configuration.
+     */
+    PDMDRV_VALIDATE_CONFIG_RETURN(pDrvIns, "", "");
+
+    /*
+     * Try attach driver below and query it's media interface.
+     */
+    int rc = PDMDrvHlpAttach(pDrvIns, fFlags, &pThis->pDrvBase);
+    if (RT_FAILURE(rc))
+        return rc;
+
+    /*
+     * Query the media interface.
+     */
+    pThis->pDrvMedia = PDMIBASE_QUERY_INTERFACE(pThis->pDrvBase, PDMIMEDIA);
+    AssertMsgReturn(RT_VALID_PTR(pThis->pDrvMedia), ("VSCSI configuration error: No media interface!\n"),
+                    VERR_PDM_MISSING_INTERFACE);
+
+    /* Query the extended media interface. */
+    pThis->pDrvMediaEx = PDMIBASE_QUERY_INTERFACE(pThis->pDrvBase, PDMIMEDIAEX);
+    AssertMsgReturn(RT_VALID_PTR(pThis->pDrvMediaEx), ("VSCSI configuration error: No extended media interface!\n"),
+                    VERR_PDM_MISSING_INTERFACE);
+
+    pThis->pDrvMount = PDMIBASE_QUERY_INTERFACE(pThis->pDrvBase, PDMIMOUNT);
+
+    PDMMEDIATYPE enmType = pThis->pDrvMedia->pfnGetType(pThis->pDrvMedia);
+    VSCSILUNTYPE enmLunType;
+    switch (enmType)
+    {
+    case PDMMEDIATYPE_HARD_DISK:
+        enmLunType = VSCSILUNTYPE_SBC;
+        break;
+    case PDMMEDIATYPE_CDROM:
+    case PDMMEDIATYPE_DVD:
+        enmLunType = VSCSILUNTYPE_MMC;
+        break;
+    default:
+        return PDMDrvHlpVMSetError(pDrvIns, VERR_PDM_UNSUPPORTED_BLOCK_TYPE, RT_SRC_POS,
+                                   N_("Only hard disks and CD/DVD-ROMs are currently supported as SCSI devices (enmType=%d)"),
+                                   enmType);
+    }
+    if (    (   enmType == PDMMEDIATYPE_DVD
+             || enmType == PDMMEDIATYPE_CDROM)
+        &&  !pThis->pDrvMount)
+    {
+        AssertMsgFailed(("Internal error: cdrom without a mountable interface\n"));
+        return VERR_INTERNAL_ERROR;
+    }
+
+    /* Create VSCSI device and LUN. */
+    pThis->VScsiIoCallbacks.pfnVScsiLunReqAllocSizeSet                   = drvscsiReqAllocSizeSet;
+    pThis->VScsiIoCallbacks.pfnVScsiLunReqAlloc                          = drvscsiReqAlloc;
+    pThis->VScsiIoCallbacks.pfnVScsiLunReqFree                           = drvscsiReqFree;
+    pThis->VScsiIoCallbacks.pfnVScsiLunMediumGetRegionCount              = drvscsiGetRegionCount;
+    pThis->VScsiIoCallbacks.pfnVScsiLunMediumQueryRegionProperties       = drvscsiQueryRegionProperties;
+    pThis->VScsiIoCallbacks.pfnVScsiLunMediumQueryRegionPropertiesForLba = drvscsiQueryRegionPropertiesForLba;
+    pThis->VScsiIoCallbacks.pfnVScsiLunMediumEject                       = drvscsiEject;
+    pThis->VScsiIoCallbacks.pfnVScsiLunReqTransferEnqueue                = drvscsiReqTransferEnqueue;
+    pThis->VScsiIoCallbacks.pfnVScsiLunGetFeatureFlags                   = drvscsiGetFeatureFlags;
+    pThis->VScsiIoCallbacks.pfnVScsiLunMediumSetLock                     = drvscsiSetLock;
+    pThis->VScsiIoCallbacks.pfnVScsiLunQueryInqStrings                   = drvscsiQueryInqStrings;
+
+    rc = VSCSIDeviceCreate(&pThis->hVScsiDevice, drvscsiIoReqVScsiReqCompleted, pThis);
+    AssertMsgReturn(RT_SUCCESS(rc), ("Failed to create VSCSI device rc=%Rrc\n", rc), rc);
+    rc = VSCSILunCreate(&pThis->hVScsiLun, enmLunType, &pThis->VScsiIoCallbacks,
+                        pThis);
+    AssertMsgReturn(RT_SUCCESS(rc), ("Failed to create VSCSI LUN rc=%Rrc\n", rc), rc);
+    rc = VSCSIDeviceLunAttach(pThis->hVScsiDevice, pThis->hVScsiLun, 0);
+    AssertMsgReturn(RT_SUCCESS(rc), ("Failed to attached the LUN to the SCSI device\n"), rc);
+
+    /// @todo This is a very hacky way of telling the LUN whether a medium was mounted.
+    // The mount/unmount interface doesn't work in a very sensible manner!
+    if (pThis->pDrvMount)
+    {
+        if (pThis->pDrvMount->pfnIsMounted(pThis->pDrvMount))
+        {
+            rc = VINF_SUCCESS; VSCSILunMountNotify(pThis->hVScsiLun);
+            AssertMsgReturn(RT_SUCCESS(rc), ("Failed to notify the LUN of media being mounted\n"), rc);
+        }
+        else
+        {
+            rc = VINF_SUCCESS; VSCSILunUnmountNotify(pThis->hVScsiLun);
+            AssertMsgReturn(RT_SUCCESS(rc), ("Failed to notify the LUN of media being unmounted\n"), rc);
+        }
+    }
+
+    uint32_t fFeatures = 0;
+    rc = pThis->pDrvMediaEx->pfnQueryFeatures(pThis->pDrvMediaEx, &fFeatures);
+    if (RT_FAILURE(rc))
+        return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS,
+                                   N_("VSCSI configuration error: Failed to query features of device"));
+    if (fFeatures & PDMIMEDIAEX_FEATURE_F_DISCARD)
+        LogRel(("SCSI#%d: Enabled UNMAP support\n", pDrvIns->iInstance));
+
+    rc = PDMDrvHlpQueueCreate(pDrvIns, sizeof(DRVSCSIEJECTSTATE), 1, 0, drvscsiR3NotifyQueueConsumer,
+                              "SCSI-Eject", &pThis->hQueue);
+    if (RT_FAILURE(rc))
+        return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS,
+                                   N_("VSCSI configuration error: Failed to create notification queue"));
+
+    return VINF_SUCCESS;
+}
+
+/**
+ * SCSI driver registration record.
+ */
+const PDMDRVREG g_DrvSCSI =
+{
+    /* u32Version */
+    PDM_DRVREG_VERSION,
+    /* szName */
+    "SCSI",
+    /* szRCMod */
+    "",
+    /* szR0Mod */
+    "",
+    /* pszDescription */
+    "Generic SCSI driver.",
+    /* fFlags */
+    PDM_DRVREG_FLAGS_HOST_BITS_DEFAULT,
+    /* fClass. */
+    PDM_DRVREG_CLASS_SCSI,
+    /* cMaxInstances */
+    ~0U,
+    /* cbInstance */
+    sizeof(DRVSCSI),
+    /* pfnConstruct */
+    drvscsiConstruct,
+    /* pfnDestruct */
+    drvscsiDestruct,
+    /* pfnRelocate */
+    NULL,
+    /* pfnIOCtl */
+    NULL,
+    /* pfnPowerOn */
+    NULL,
+    /* pfnReset */
+    drvscsiReset,
+    /* pfnSuspend */
+    drvscsiSuspend,
+    /* pfnResume */
+    NULL,
+    /* pfnAttach */
+    drvscsiAttach,
+    /* pfnDetach */
+    drvscsiDetach,
+    /* pfnPowerOff */
+    drvscsiPowerOff,
+    /* pfnSoftReset */
+    NULL,
+    /* u32EndVersion */
+    PDM_DRVREG_VERSION
+};