Re: mm question

From: Martin J. Bligh (
Date: Mon Dec 10 2001 - 12:09:49 EST

>> > I was hoping for something more elegant, but I am not adverse to writing
>> > my own get_free_page_from_range().
>> Thats not a trivial task.
> Better than giving up.. Unfortunately looking around in
> linux/Documentation and drivers did not yield much in terms of
> explanation. I know I can use mem_map_reserve to reserve a page but I
> don't know how to get page struct from a physical address nor which lock
> to use when messing with this.

If you don't have any ISA DMA going on in the system, you might consider
bastardising the ZONE_DMA page range by moving the boundary up to
64Mb, then fixing the allocator not to fail back ZONE_NORMAL et al
allocations to ZONE_DMA. Thus what was originally ZONE_DMA becomes
a sort of ZONE_NO_DMA. Not in the slightest bit pretty, but it might be easier
to implement. Depends if you ever want it to get back into the main tree,
I guess ;-)


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This archive was generated by hypermail 2b29 : Sat Dec 15 2001 - 21:00:18 EST