diff --git a/reactos/drivers/filesystems/fastfat/cleanup.c b/reactos/drivers/filesystems/fastfat/cleanup.c
index 97c2515116e..f9bde77d206 100644
--- a/reactos/drivers/filesystems/fastfat/cleanup.c
+++ b/reactos/drivers/filesystems/fastfat/cleanup.c
@@ -24,6 +24,7 @@ VfatCleanupFile(
     PVFAT_IRP_CONTEXT IrpContext)
 {
     PVFATFCB pFcb;
+    PDEVICE_EXTENSION DeviceExt = IrpContext->DeviceExt;
     PFILE_OBJECT FileObject = IrpContext->FileObject;
 
     DPRINT("VfatCleanupFile(DeviceExt %p, FileObject %p)\n",
@@ -37,6 +38,7 @@ VfatCleanupFile(
     if (pFcb->Flags & FCB_IS_VOLUME)
     {
         pFcb->OpenHandleCount--;
+        DeviceExt->OpenHandleCount--;
 
         if (pFcb->OpenHandleCount != 0)
         {
@@ -63,6 +65,7 @@ VfatCleanupFile(
                            FileObject->FsContext2);
 
         pFcb->OpenHandleCount--;
+        DeviceExt->OpenHandleCount--;
 
         if (!(*pFcb->Attributes & FILE_ATTRIBUTE_DIRECTORY) &&
             FsRtlAreThereCurrentFileLocks(&pFcb->FileLock))
diff --git a/reactos/drivers/filesystems/fastfat/create.c b/reactos/drivers/filesystems/fastfat/create.c
index bccbdb77183..6314c52ae3c 100644
--- a/reactos/drivers/filesystems/fastfat/create.c
+++ b/reactos/drivers/filesystems/fastfat/create.c
@@ -473,10 +473,18 @@ VfatCreateFile(
         return STATUS_INVALID_PARAMETER;
     }
 
+    /* Deny create if the volume is locked */
+    if (DeviceExt->Flags & VCB_VOLUME_LOCKED)
+    {
+        return STATUS_ACCESS_DENIED;
+    }
+
     /* This a open operation for the volume itself */
     if (FileObject->FileName.Length == 0 &&
         (FileObject->RelatedFileObject == NULL || FileObject->RelatedFileObject->FsContext2 != NULL))
     {
+        DPRINT1("Volume opening\n");
+
         if (RequestedDisposition != FILE_OPEN &&
             RequestedDisposition != FILE_OPEN_IF)
         {
@@ -497,6 +505,7 @@ VfatCreateFile(
 
         pFcb = DeviceExt->VolumeFcb;
         vfatAttachFCBToFileObject(DeviceExt, pFcb, FileObject);
+        DeviceExt->OpenHandleCount++;
 
         Irp->IoStatus.Information = FILE_OPENED;
         return STATUS_SUCCESS;
@@ -639,6 +648,7 @@ VfatCreateFile(
             }
 
             pFcb->OpenHandleCount++;
+            DeviceExt->OpenHandleCount++;
         }
         else if (ParentFcb != NULL)
         {
@@ -884,6 +894,7 @@ VfatCreateFile(
     }
 
     pFcb->OpenHandleCount++;
+    DeviceExt->OpenHandleCount++;
 
     /* FIXME : test write access if requested */
 
diff --git a/reactos/drivers/filesystems/fastfat/fsctl.c b/reactos/drivers/filesystems/fastfat/fsctl.c
index e0a1608600c..19f97854ea8 100644
--- a/reactos/drivers/filesystems/fastfat/fsctl.c
+++ b/reactos/drivers/filesystems/fastfat/fsctl.c
@@ -612,6 +612,8 @@ VfatMount(
     FsRtlNotifyInitializeSync(&DeviceExt->NotifySync);
     InitializeListHead(&DeviceExt->NotifyList);
 
+    DPRINT1("Mount success\n");
+
     Status = STATUS_SUCCESS;
 
 ByeBye:
@@ -855,6 +857,72 @@ VfatMarkVolumeDirty(
     return Status;
 }
 
+static
+NTSTATUS
+VfatLockOrUnlockVolume(
+    PVFAT_IRP_CONTEXT IrpContext,
+    BOOLEAN Lock)
+{
+    PFILE_OBJECT FileObject;
+    PDEVICE_EXTENSION DeviceExt;
+
+    DPRINT1("VfatLockOrUnlockVolume(%p, %d)\n", IrpContext, Lock);
+
+    DeviceExt = IrpContext->DeviceExt;
+    FileObject = IrpContext->FileObject;
+
+    /* Only allow locking with the volume open */
+    if (FileObject->FsContext != DeviceExt->VolumeFcb)
+    {
+        return STATUS_ACCESS_DENIED;
+    }
+
+    /* Bail out if it's already in the demanded state */
+    if (((DeviceExt->Flags & VCB_VOLUME_LOCKED) && Lock) ||
+        (!(DeviceExt->Flags & VCB_VOLUME_LOCKED) && !Lock))
+    {
+        return STATUS_ACCESS_DENIED;
+    }
+
+    /* Deny locking if we're not alone */
+    if (Lock && DeviceExt->OpenHandleCount != 1)
+    {
+        return STATUS_ACCESS_DENIED;
+    }
+
+    /* Finally, proceed */
+    if (Lock)
+    {
+        DeviceExt->Flags |= VCB_VOLUME_LOCKED;
+    }
+    else
+    {
+        DeviceExt->Flags &= ~VCB_VOLUME_LOCKED;
+    }
+
+    return STATUS_SUCCESS;
+}
+
+static
+NTSTATUS
+VfatDismountVolume(
+    PVFAT_IRP_CONTEXT IrpContext)
+{
+    PDEVICE_EXTENSION DeviceExt;
+
+    DPRINT1("VfatDismountVolume(%p)\n", IrpContext);
+
+    DeviceExt = IrpContext->DeviceExt;
+
+    if (!(DeviceExt->Flags & VCB_VOLUME_LOCKED))
+    {
+        return STATUS_ACCESS_DENIED;
+    }
+
+    UNIMPLEMENTED;
+    return STATUS_NOT_IMPLEMENTED;
+}
+
 /*
  * FUNCTION: File system control
  */
@@ -898,6 +966,18 @@ VfatFileSystemControl(
                     Status = VfatMarkVolumeDirty(IrpContext);
                     break;
 
+                case FSCTL_LOCK_VOLUME:
+                    Status = VfatLockOrUnlockVolume(IrpContext, TRUE);
+                    break;
+
+                case FSCTL_UNLOCK_VOLUME:
+                    Status = VfatLockOrUnlockVolume(IrpContext, FALSE);
+                    break;
+
+                case FSCTL_DISMOUNT_VOLUME:
+                    Status = VfatDismountVolume(IrpContext);
+                    break;
+
                 default:
                     Status = STATUS_INVALID_DEVICE_REQUEST;
             }
diff --git a/reactos/drivers/filesystems/fastfat/vfat.h b/reactos/drivers/filesystems/fastfat/vfat.h
index 416fa74c9fa..c35b73540b6 100644
--- a/reactos/drivers/filesystems/fastfat/vfat.h
+++ b/reactos/drivers/filesystems/fastfat/vfat.h
@@ -296,6 +296,9 @@ typedef struct DEVICE_EXTENSION
     /* Notifications */
     LIST_ENTRY NotifyList;
     PNOTIFY_SYNC NotifySync;
+
+    /* Incremented on IRP_MJ_CREATE, decremented on IRP_MJ_CLEANUP */
+    ULONG OpenHandleCount;
 } DEVICE_EXTENSION, VCB, *PVCB;
 
 typedef struct