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i try implement basic support for cache on file.
but unclear how correct process IRP_MJ_CLEANUP / IRP_MJ_CLOSE - how uninitialize cache
if i not create section on file, but only write to, read from file - all until look like ok.
i view both cached I/O and than non cached paged I/O.
after i close (last) file handle - driver receive both IRP_MJ_CLEANUP / IRP_MJ_CLOSE and all ok. file references reached 0
but in case i create and map section on file - file reference count never reach 0
basically i do from user mode :
NtOpenFile(&hFile, FILE_ALL_ACCESS, ..., FILE_SYNCHRONOUS_IO_NONALERT); NtCreateSection(&hSection, SECTION_ALL_ACCESS, 0, 0, PAGE_READWRITE, SEC_COMMIT, hFile); NtClose(hFile); ZwMapViewOfSection(hSection, ... PAGE_READWRITE); NtClose(hSection); ZwUnmapViewOfSection(NtCurrentProcess(), BaseAddress);
section created and mapped ok. i can read data from view - driver receive IRP_NOCACHE|IRP_PAGING_IO requests .
but after ZwUnmapViewOfSection - i not got any notification in driver. and cache manager still hold several references to my file.
because i not got notification on last ZwUnmapViewOfSection i can not call say CcPurgeCacheSection/CcUninitializeCacheMap or something else
how correct handle this situation ?
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