On Mon, Jun 20, 2011 at 2:59 PM, Daniel Glöckner [off-list ref] wrote:

On Mon, Jun 20, 2011 at 01:22:13PM +0800, Bob Liu wrote:

quoted

Function remap_pfn_range() means map physical address pfn<<PAGE_SHIFT to
user addr.

For nommu arch it's implemented by vma->vm_start = pfn << PAGE_SHIFT which is
wrong acroding the original meaning of this function.

Some driver developer using remap_pfn_range() with correct parameter will get
unexpected result because vm_start is changed.

It should be implementd just like addr = pfn << PAGE_SHIFT which is meanless
on nommu arch, so this patch just make it simply return 0.

I'd return -EINVAL if addr != pfn << PAGE_SHIFT.

okay.

And I can imagine architectures wanting to do something with the prot flags.

Actually it's just a fake function on nommu arch, so in my opinion
we'd better keep it simple
as current.

-- 
Regards,
--Bob

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