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SubjectRe: DMA and Cache coherency on machines without hardware enforced cache coherency.
Hi,

> ioremap_nocache(). You can also use ioremap_nocache() on allocated pages
> (it's a page granularity thing) via doing something like:
>
> page = __get_free_pages(whatever, order);
> ptr = ioremap_nocache(virt_to_phys(page), 1 <<
> (order+PAGE_SHIFT));

But the problem is that this mapping is never released if you call
iounmap() and if you remove that check there, vfree tries to free not only
the mapping but also any non reserved page. I think we really need a real
memremap() interface...

bye, Roman



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