From f4de97f3c6c9a006fbf05e8d4a69dde0bb0cf1f9 Mon Sep 17 00:00:00 2001
From: Bill Zissimopoulos <billziss@navimatics.com>
Date: Sun, 29 Nov 2015 13:21:32 -0800
Subject: [PATCH] sys: FspFsctlMountVolume

---
 src/dll/fsctl.c  |  4 ++--
 src/sys/driver.h |  4 ++++
 src/sys/fsctl.c  | 41 +++++++++++++++++++++++++++++++++++++----
 3 files changed, 43 insertions(+), 6 deletions(-)

diff --git a/src/dll/fsctl.c b/src/dll/fsctl.c
index d2a6268b..48584218 100644
--- a/src/dll/fsctl.c
+++ b/src/dll/fsctl.c
@@ -48,7 +48,7 @@ FSP_API NTSTATUS FspFsctlCreateVolume(PWSTR DevicePath,
     *ParamsBuf = *Params;
 
     DeviceHandle = CreateFileW(DevicePathBuf,
-        0, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, 0, OPEN_EXISTING, 0, 0);
+        0, FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING, 0, 0);
     if (INVALID_HANDLE_VALUE == DeviceHandle)
     {
         Result = FspNtStatusFromWin32(GetLastError());
@@ -84,7 +84,7 @@ FSP_API NTSTATUS FspFsctlOpenVolume(PWSTR VolumePath,
     GlobalDevicePath(DevicePathBuf, sizeof DevicePathBuf, VolumePath);
 
     VolumeHandle = CreateFileW(DevicePathBuf,
-        0, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, 0, OPEN_EXISTING, 0, 0);
+        0, FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING, 0, 0);
     if (INVALID_HANDLE_VALUE == VolumeHandle)
     {
         Result = FspNtStatusFromWin32(GetLastError());
diff --git a/src/sys/driver.h b/src/sys/driver.h
index 28e35b4e..9d8f0be2 100644
--- a/src/sys/driver.h
+++ b/src/sys/driver.h
@@ -261,6 +261,7 @@ typedef struct
 {
     FSP_DEVICE_EXTENSION Base;
     PDEVICE_OBJECT FsvrtDeviceObject;
+    PVPB SwapVpb;
 } FSP_FSVOL_DEVICE_EXTENSION;
 static inline
 FSP_DEVICE_EXTENSION *FspDeviceExtension(PDEVICE_OBJECT DeviceObject)
@@ -270,16 +271,19 @@ FSP_DEVICE_EXTENSION *FspDeviceExtension(PDEVICE_OBJECT DeviceObject)
 static inline
 FSP_FSCTL_DEVICE_EXTENSION *FspFsctlDeviceExtension(PDEVICE_OBJECT DeviceObject)
 {
+    ASSERT(FspFsctlDeviceExtensionKind == ((FSP_DEVICE_EXTENSION *)DeviceObject->DeviceExtension)->Kind);
     return DeviceObject->DeviceExtension;
 }
 static inline
 FSP_FSVRT_DEVICE_EXTENSION *FspFsvrtDeviceExtension(PDEVICE_OBJECT DeviceObject)
 {
+    ASSERT(FspFsvrtDeviceExtensionKind == ((FSP_DEVICE_EXTENSION *)DeviceObject->DeviceExtension)->Kind);
     return DeviceObject->DeviceExtension;
 }
 static inline
 FSP_FSVOL_DEVICE_EXTENSION *FspFsvolDeviceExtension(PDEVICE_OBJECT DeviceObject)
 {
+    ASSERT(FspFsvolDeviceExtensionKind == ((FSP_DEVICE_EXTENSION *)DeviceObject->DeviceExtension)->Kind);
     return DeviceObject->DeviceExtension;
 }
 
diff --git a/src/sys/fsctl.c b/src/sys/fsctl.c
index ccdd82ca..a1eb6f29 100644
--- a/src/sys/fsctl.c
+++ b/src/sys/fsctl.c
@@ -93,7 +93,7 @@ static NTSTATUS FspFsctlCreateVolume(
         FspIoqInitialize(&FsvrtDeviceExtension->Ioq);
         RtlCopyMemory(FspFsvrtDeviceExtension(FsvrtDeviceObject)->SecurityDescriptorBuf,
             SecurityDescriptorBuf, SecurityDescriptorSize);
-        ClearFlag(FsvrtDeviceObject->DO_DEVICE_INITIALIZING);
+        ClearFlag(FsvrtDeviceObject->Flags, DO_DEVICE_INITIALIZING);
         Irp->IoStatus.Information = DeviceName.Length + 1;
     }
 
@@ -109,10 +109,14 @@ static NTSTATUS FspFsctlMountVolume(
     PAGED_CODE();
 
     NTSTATUS Result;
-    PDEVICE_OBJECT RealDevice = IrpSp->Parameters.MountVolume.Vpb->RealDevice;
+    PVPB Vpb = IrpSp->Parameters.MountVolume.Vpb;
+    PVPB SwapVpb = 0;
+    PDEVICE_OBJECT FsvrtDeviceObject = Vpb->RealDevice;
+    PDEVICE_OBJECT FsvolDeviceObject;
+    FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension;
 
     /* check the passed in volume object; it must be one of our own */
-    Result = FspHasDeviceObject(DeviceObject->DriverObject, RealDevice);
+    Result = FspHasDeviceObject(DeviceObject->DriverObject, FsvrtDeviceObject);
     if (!NT_SUCCESS(Result))
     {
         if (STATUS_NO_SUCH_DEVICE == Result)
@@ -120,9 +124,38 @@ static NTSTATUS FspFsctlMountVolume(
         else
             return Result;
     }
-    if (FILE_DEVICE_VIRTUAL_DISK != RealDevice->DeviceType)
+    if (FILE_DEVICE_VIRTUAL_DISK != FsvrtDeviceObject->DeviceType)
         return STATUS_UNRECOGNIZED_VOLUME;
 
+    /* preallocate swap VPB */
+    SwapVpb = ExAllocatePoolWithTag(NonPagedPool, sizeof *SwapVpb, FSP_TAG);
+    if (0 == SwapVpb)
+        return STATUS_INSUFFICIENT_RESOURCES;
+    RtlZeroMemory(SwapVpb, sizeof *Vpb);
+
+    /* create the file system device object */
+    Result = IoCreateDevice(DeviceObject->DriverObject,
+        sizeof(FSP_FSVOL_DEVICE_EXTENSION), 0, DeviceObject->DeviceType,
+        0, FALSE,
+        &FsvolDeviceObject);
+    if (NT_SUCCESS(Result))
+    {
+        FsvolDeviceObject->SectorSize =
+            FspFsvrtDeviceExtension(FsvrtDeviceObject)->VolumeParams.SectorSize;
+        FsvolDeviceExtension = FspFsvolDeviceExtension(FsvolDeviceObject);
+        FsvolDeviceExtension->FsvrtDeviceObject = FsvrtDeviceObject;
+        FsvolDeviceExtension->SwapVpb = SwapVpb;
+        ClearFlag(FsvolDeviceObject->Flags, DO_DEVICE_INITIALIZING);
+        Vpb->VolumeLabelLength = 0;
+        Vpb->DeviceObject = FsvolDeviceObject;
+        Irp->IoStatus.Information = 0;
+        SwapVpb = 0;
+    }
+
+    /* free swap VPB if we failed */
+    if (0 != SwapVpb)
+        ExFreePoolWithTag(SwapVpb, FSP_TAG);
+
     return Result;
 }