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include vmm.inc
 
VMMcall _GetFreePageCount, <flags>
 
mov     dword ptr [FreePages], eax      ; number of free pages
mov     dword ptr [LockablePages], edx  ; number of lockable pages
 
The _GetFreePageCount service returns the number of pages in the free list.
This service also returns the number of free pages that can be allocated as
locked pages. Virtual devices can allocate free pages using the
_PageAllocate service.
 
Parameter  Description
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flags      Specifies the operation flags. This parameter must be set to 0.
 
Return Value
 
The EAX register contains the count of free pages, and the EDX register
contains the count of pages available for allocation as locked pages.
 
Comments
 
In a demand-paged virtual memory system such as Windows, the number of free
pages is usually very close to 0, so the count of pages available for
locking is usually a better indicator of available memory. However, virtual
devices must not rely on the count of free pages being less than or equal to
the count of pages to lock. No guarantees can be made about the length of
time the information returned by this service remains accurate.
 
Uses
 
EAX, EDX
 
See Also
 
_PageAllocate
 
 
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