Previously, when creating a file section, Mm requested Cc to cache the file, then Cc would request pages from Mm, then Mm would request them back to serve its file-mapping role
Now, Mm does it all by itself. If file cahcing is requested by the FS driver, then Cc creates a file mapping and uses that to serve its purpose.
This is a rewrite of Cc
If a thread calls MiInsertPageInFreeList after the zero page thread has
woken up from its wait but before it acquired the PFN lock,
MmZeroingPageEvent might get set again even though there is no additional
work to be done.
By setting MmZeroingPageThreadActive together with the event, the variable
correctly indicates for future callers that the zero thread will process
newly added free pages.
This partially reverts r72990.
