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include vmm.inc
 
VMMcall _PageReAllocate, <hMem, nPages, flags>
 
mov     ecx, eax                ; zero in eax and edx if error
or      ecx, edx
jz      error
 
mov     [Handle], eax           ; memory handle
mov     [Address], edx          ; physical address of start of memory block
 
The _PageReAllocate service reallocates and optionally reinitializes an
existing memory block. The service can increase or decrease the number of
pages in the memory block.
 
Parameter  Description
────────────────────────────────────────────────────────────────────────────
 
hMem       Specifies a handle identifying the memory block to reallocate.
           This handle must have been previously created using the
           _PageAllocate or _PageReAllocate service.
 
nPages     Specifies the number of pages in the reallocated memory block.
           This parameter must not be set to zero. To free a memory block,
           use the _PageFree service.
 
flags      Specifies the operation flags. This parameter can be a
           combination of the following values:
 
           Value           Meaning
           ─────────────────────────────────────────────────────────────────
           PageZeroInit    Fills any new pages with zeros. All existing
                           pages remain unchanged.
 
           PageZeroReInit  Fills all pages, new and existing, with zeros.
 
           PageNoCopy      Does not preserve contents of existing pages. If
                           this value is not given, the service preserves
                           the contents of each existing page by copying the
                           contents of the old memory block into the
                           corresponding pages of the new block.
 
           PageLocked      Locks the allocated pages in the memory. The
                           pages can be subsequently unlocked using the
                           _PageUnLock service. The service locks the memory
                           block regardless of the type of virtual pageswap
                           device present.
 
           PageLockedIfDP  Locks the allocated pages in the memory only if
                           the virtual pageswap device uses MS-DOS or BIOS
                           functions to write to the hardware. If the pages
                           are locked, they can be subsequently unlocked
                           using the _PageUnLock service.
 
                           A virtual device must not specify the
                           PageLockedIfDP value until after the
                           Init_Complete message has been processed by all
                           virtual devices.
 
           All other values are reserved.
 
Return Value
 
The EAX register contains the memory handle of the new memory block, and the
EDX register contains the ring-0 linear address of the block. Otherwise, the
EAX and EDX registers both contain zero to indicate an error such as
insufficient memory, an invalid memory handle, or wrong memory type.
 
Comments
 
If successful, this service frees the old memory block, making the old
memory handle and starting address invalid. If this service returns an
error, the old memory handle and starting address remain valid.
 
If the specified memory handle identifies a fixed memory block (allocated
using the PageFixed value), this service implicitly allocates fixed pages
for the new memory block.
 
If the specified handle identifies an aligned memory block (allocated using
the PageUseAlign value), this service returns an error.
 
Virtual devices must never rely on the new and old memory handles being the
same, or the new and old starting addresses being equal.
 
The action specified by the PageLockedIfDP value is available only after the
virtual pageswap device has been initialized.
 
Uses
 
EAX, EDX
 
See Also
 
_PageAllocate, _PageFree, _PageLock, _PageUnLock
 
 
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