[WDF] Add Windows Driver Framework files

Takern from Microsoft GitHub repo:
d9c6040fe9

Licensed under MIT

sdk/lib/drivers/wdf/shared/inc/private/km/fxrequestbufferkm.hpp

@@ -0,0 +1,111 @@
+/*++
+
+  Copyright (c) Microsoft Corporation
+
+  Module Name:
+
+  FxRequestBufferKm.hpp
+
+  Abstract:
+
+  This module implements km specific functions for FxRequestBuffer.
+
+  Author:
+
+
+
+  Environment:
+
+  Kernel mode only
+
+  Revision History:
+
+  --*/
+
+#ifndef _FXREQUESTBUFFERKM_HPP_
+#define _FXREQUESTBUFFERKM_HPP_
+
+__inline
+VOID
+FxRequestBuffer::SetMdl(
+    __in PMDL Mdl,
+    __in ULONG Length
+    )
+{
+    DataType = FxRequestBufferMdl;
+    u.Mdl.Mdl = Mdl;
+    u.Mdl.Length = Length;
+}
+
+FORCEINLINE
+NTSTATUS
+FxRequestBuffer::GetOrAllocateMdlWorker(
+    __in PFX_DRIVER_GLOBALS FxDriverGlobals,
+    __deref_out PMDL*       Mdl,
+    __in BOOLEAN *          ReuseMdl,
+    __in LONG               Length,
+    __in PVOID              Buffer,
+    __inout size_t*         SizeOfMdl,
+    __in BOOLEAN            UnlockWhenFreed,
+    __deref_out_opt PMDL*   MdlToFree
+        )
+{
+    size_t sizeofCurrentMdl;
+    sizeofCurrentMdl = MmSizeOfMdl(Buffer, Length);
+
+    //
+    // Caller of this function (GetOrAllocateMdl) verifies that pages
+    // are already unlocked. Asserting here, in case we start using this
+    // function elsewhere.
+    //
+    // This is why we don't unlock pages either in reuse or non-reuse case.
+    //
+    ASSERT(UnlockWhenFreed == FALSE);
+     UNREFERENCED_PARAMETER(UnlockWhenFreed); //for fre build
+
+    //
+    // If ReuseMdl is TRUE then the Mdl to be reused is passed in.
+    //
+    if (*ReuseMdl && sizeofCurrentMdl <= *SizeOfMdl) {
+        MmPrepareMdlForReuse(*MdlToFree);
+        *Mdl = *MdlToFree;
+    }
+    else {
+        *ReuseMdl = FALSE;
+
+        //
+        // Since *Mdl may have the original IRP Mdl
+        // free *MdlToFree and not *Mdl
+        //
+        if (*MdlToFree != NULL) {
+            FxMdlFree(FxDriverGlobals, *MdlToFree);
+            *MdlToFree = NULL;
+             if (SizeOfMdl != NULL) {
+                *SizeOfMdl = 0;
+            }
+        }
+
+        *Mdl = FxMdlAllocate(FxDriverGlobals,
+                             NULL, // owning FxObject
+                             Buffer,
+                             Length,
+                             FALSE,
+                             FALSE);
+
+        if (*Mdl == NULL) {
+
+            ASSERT(SizeOfMdl ? (*SizeOfMdl == 0) : TRUE);
+
+            return STATUS_INSUFFICIENT_RESOURCES;
+        }
+
+        if (SizeOfMdl != NULL) {
+            *SizeOfMdl  = sizeofCurrentMdl;
+        }
+    }
+
+    return STATUS_SUCCESS;
+}
+
+
+#endif // _FXREQUESTBUFFERKM_HPP_