Re: Device driver memory 'mmap()' function helper cleanup

[Linus Torvalds]

On Wed, Apr 17, 2013 at 10:11 AM, David Miller <davem@xxxxxxxxxxxxx> wrote:
>
> Yeah, the only thing special we do on sparc is interpret the PFN
> specially.  We munge it into the real physical address and then
> pass it all down to remap_pfn_range() to do the real work.

So the main thing I want to check is that *if* it's given a regular
RAM physical address, it still works?

Some drivers basically allocate DMA memory and then pass on the
resulting physical address to this. Others pass in the PCI BAR
addresses etc. And some try to use "remap_pfn_range()", and others try
to use "io_remap_pfn_range()", and quite frankly, from what I can tell
we can just always use the "io_" version because it ends up being a
proper superset.

I'm pretty sure it works fine the way I read it, but I'm just verifying..

              Linus
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