VOID
CmpCleanUpKcbValueCache(
PCM_KEY_CONTROL_BLOCK KeyControlBlock
)
/*++
Routine Description:
Clean up cached value/data that are associated to this key.
Arguments:
KeyControlBlock - pointer to a key control block.
Return Value:
NONE.
--*/
{
ULONG i;
PULONG_PTR CachedList;
PCELL_DATA pcell;
ULONG realsize;
BOOLEAN small;
if (CMP_IS_CELL_CACHED(KeyControlBlock->ValueCache.ValueList)) {
CachedList = (PULONG_PTR) CMP_GET_CACHED_CELLDATA(KeyControlBlock->ValueCache.ValueList);
for (i = 0; i < KeyControlBlock->ValueCache.Count; i++) {
if (CMP_IS_CELL_CACHED(CachedList[i])) {
// Trying to catch the BAD guy who writes over our pool.
CmpMakeSpecialPoolReadWrite( CMP_GET_CACHED_ADDRESS(CachedList[i]) );
ExFreePool((PVOID) CMP_GET_CACHED_ADDRESS(CachedList[i]));
}
}
// Trying to catch the BAD guy who writes over our pool.
CmpMakeSpecialPoolReadWrite( CMP_GET_CACHED_ADDRESS(KeyControlBlock->ValueCache.ValueList) );
ExFreePool((PVOID) CMP_GET_CACHED_ADDRESS(KeyControlBlock->ValueCache.ValueList));
// Mark the ValueList as NULL
KeyControlBlock->ValueCache.ValueList = HCELL_NIL;
} else if (KeyControlBlock->ExtFlags & CM_KCB_SYM_LINK_FOUND) {
//
// This is a symbolic link key with symbolic name resolved.
// Dereference to its real kcb and clear the bit.
//
if ((KeyControlBlock->ValueCache.RealKcb->RefCount == 1) && !(KeyControlBlock->ValueCache.RealKcb->Delete)) {
KeyControlBlock->ValueCache.RealKcb->ExtFlags |= CM_KCB_NO_DELAY_CLOSE;
}
CmpDereferenceKeyControlBlockWithLock(KeyControlBlock->ValueCache.RealKcb);
KeyControlBlock->ExtFlags &= ~CM_KCB_SYM_LINK_FOUND;
}
}
VALUE_SEARCH_RETURN_TYPE
CmpGetValueListFromCache(
IN PCM_KEY_CONTROL_BLOCK KeyControlBlock,
OUT PCELL_DATA *List,
OUT BOOLEAN *IndexCached,
OUT PHCELL_INDEX ValueListToRelease
)
/*++
Routine Description:
Get the Valve Index Array. Check if it is already cached, if not, cache it and return
the cached entry.
Arguments:
Hive - pointer to hive control structure for hive of interest
ChildList - pointer/index to the Value Index array
IndexCached - Indicating whether Value Index list is cached or not.
Return Value:
Pointer to the Valve Index Array.
NULL when we could not map view
--*/
{
HCELL_INDEX CellToRelease;
PCACHED_CHILD_LIST ChildList;
PHHIVE Hive;
#ifndef _WIN64
ULONG AllocSize;
PCM_CACHED_VALUE_INDEX CachedValueIndex;
ULONG i;
#endif
ASSERT_KCB_LOCKED(KeyControlBlock);
Hive = KeyControlBlock->KeyHive;
ChildList = &(KeyControlBlock->ValueCache);
*ValueListToRelease = HCELL_NIL;
#ifndef _WIN64
*IndexCached = TRUE;
if (CMP_IS_CELL_CACHED(ChildList->ValueList)) {
//
// The entry is already cached.
//
*List = CMP_GET_CACHED_CELLDATA(ChildList->ValueList);
} else {
//
// The entry is not cached. The element contains the hive index.
// ensure exclusive lock.
//
if( (CmpIsKCBLockedExclusive(KeyControlBlock) == FALSE) &&
(CmpTryConvertKCBLockSharedToExclusive(KeyControlBlock) == FALSE) ) {
//
// need to upgrade lock to exclusive
//
return SearchNeedExclusiveLock;
}
CellToRelease = CMP_GET_CACHED_CELL_INDEX(ChildList->ValueList);
*List = (PCELL_DATA) HvGetCell(Hive, CellToRelease);
if( *List == NULL ) {
//
// we couldn't map a view for this cell
//
*IndexCached = FALSE;
return SearchFail;
}
//
// Allocate a PagedPool to cache the value index cell.
//
AllocSize = ChildList->Count * sizeof(ULONG_PTR) + FIELD_OFFSET(CM_CACHED_VALUE_INDEX, Data);
CachedValueIndex = (PCM_CACHED_VALUE_INDEX) ExAllocatePoolWithTag(PagedPool, AllocSize, CM_CACHE_VALUE_INDEX_TAG);
if (CachedValueIndex) {
CachedValueIndex->CellIndex = CMP_GET_CACHED_CELL_INDEX(ChildList->ValueList);
#pragma prefast(suppress:12009, "no overflow")
for (i=0; i<ChildList->Count; i++) {
CachedValueIndex->Data.List[i] = (ULONG_PTR) (*List)->u.KeyList[i];
}
ChildList->ValueList = CMP_MARK_CELL_CACHED(CachedValueIndex);
// Trying to catch the BAD guy who writes over our pool.
CmpMakeSpecialPoolReadOnly( CachedValueIndex );
//
// Now we have the stuff cached, use the cache data.
//
*List = CMP_GET_CACHED_CELLDATA(ChildList->ValueList);
} else {
//
// If the allocation fails, just do not cache it. continue.
//
*IndexCached = FALSE;
}
*ValueListToRelease = CellToRelease;
}
#else
CellToRelease = CMP_GET_CACHED_CELL_INDEX(ChildList->ValueList);
*List = (PCELL_DATA) HvGetCell(Hive, CellToRelease);
*IndexCached = FALSE;
if( *List == NULL ) {
//
// we couldn't map a view for this cell
// OBS: we can drop this as we return List anyway; just for clarity
//
return SearchFail;
}
*ValueListToRelease = CellToRelease;
#endif
return SearchSuccess;
}
