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Subject: Re: Unmapping pages from the linear addressing without HIGHMEM	support
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Gerhard Pircher <gerhard_pircher@gmx.net>
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> That would mean I cannot reuse the code in dma-mapping.c, right? Killing the
> BAT mappings or limiting the memory size covered by the BATs seems to be
> fairly easy, but I guess I have to setup my own page table for the reserved
> DMA memory area and implement my own alloc_pages() function!?

No, just limit the size of the BAT mapping and mark some of the top
pages of the address space reserved... That should be enough.

Ben.