[PATCHv2 2/3] i915: convert to new mount API

[Al Viro]

On Wed, Aug 07, 2019 at 08:30:02AM +0200, Christoph Hellwig wrote:
> On Tue, Aug 06, 2019 at 12:50:10AM -0700, Hugh Dickins wrote:
> > Though personally I'm averse to managing "f"objects through
> > "m"interfaces, which can get ridiculous (notably, MADV_HUGEPAGE works
> > on the virtual address of a mapping, but the huge-or-not alignment of
> > that mapping must have been decided previously).  In Google we do use
> > fcntls F_HUGEPAGE and F_NOHUGEPAGE to override on a per-file basis -
> > one day I'll get to upstreaming those.
> 
> Such an interface seems very useful, although the two fcntls seem a bit
> odd.
> 
> But I think the point here is that the i915 has its own somewhat odd
> instance of tmpfs.  If we could pass the equivalent of the huge=*
> options to shmem_file_setup all that garbage (including the
> shmem_file_setup_with_mnt function) could go away.

... or follow shmem_file_super() with whatever that fcntl maps to
internally.  I would really love to get rid of that i915 kludge.