FxRequestMemory::~FxRequestMemory(
VOID
)
/*++
Routine Description:
Destructor for this object. Does nothing with the client memory since
the client owns it.
Arguments:
None
Return Value:
None
--*/
{
//
// Non-embedded case releases resources in the destructor
// rather than Dispose to ensure all outstanding device driver
// references are gone.
//
#if (FX_CORE_MODE == FX_CORE_KERNEL_MODE)
if( m_Mdl != NULL ) {
Mx::MxUnlockPages(m_Mdl);
FxMdlFree(GetDriverGlobals(), m_Mdl);
m_Mdl = NULL;
}
#endif
if( m_Request != NULL ) {
m_Request->ReleaseIrpReference();
m_Request = NULL;
}
}
FORCEINLINE
FxIoContext::~FxIoContext(
VOID
)
{
//
// Free the buffer allocated for the request, reset m_CopyBackToBuffer
// to FALSE.
// NOTE: We delay the freeing of the buffer on purpose.
//
ClearBuffer();
//
// Free the MDL allocated for the request
//
if (m_MdlToFree != NULL) {
//
// Being defensive here, MmUnlockPages should have been done in
// ReleaseAndRestore.
//
if (m_UnlockPages) {
MmUnlockPages(m_MdlToFree);
m_UnlockPages = FALSE;
}
FxMdlFree(m_DriverGlobals, m_MdlToFree);
m_MdlToFree = NULL;
}
}
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;
}
