[RFC] early_fault handler

[Matthew Wilcox]

On Wed, Nov 13, 2013 at 07:50:46AM -0800, Dave Hansen wrote:
> On 11/13/2013 05:47 AM, Matthew Wilcox wrote:
> > (Mostly the patch is so big because I have to change the calling
> > convention of either hugetlb or hpage_xip.  I chose the latter for
> > obvious reasons).
> 
> That looks pretty sane, although hugetlbfs is _bad_ company to be in. :)

Well, I could change the calling convention for both ... passing the
mm_struct is a bit redundant, for example.

> I'm glad you also managed to nuke this gem:
> 
> > -		vmf.pgoff = (((address & PAGE_MASK) - vma->vm_start) >> PAGE_SHIFT)
> > -															+ vma->vm_pgoff;

I only moved it ...

+       unsigned long address = user_address & PAGE_MASK;
+       unsigned long pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) +
+                               vma->vm_pgoff;