[PATCH 0/26] get_user_pages() cleanup

[Jan Kara]

  Hello,

  In my quest for changing locking around page faults to make things easier for
filesystems I found out get_user_pages() users could use a cleanup.  The
knowledge about necessary locking for get_user_pages() is in tons of places in
drivers and quite a few of them actually get it wrong (don't have mmap_sem when
calling get_user_pages() or hold mmap_sem when calling copy_from_user() in the
surrounding code). Rather often this actually doesn't seem necessary. This
patch series converts lots of places to use either get_user_pages_fast()
or a new simple wrapper get_user_pages_unlocked() to remove the knowledge
of mmap_sem from the drivers. I'm still looking into converting a few remaining
drivers (most notably v4l2) which are more complex.

As I already wrote, in some cases I actually think drivers were buggy (and I
note that in corresponding changelogs). I would really like to ask respective
maintainers to have a look at the patches in their area. Also any other
comments are welcome. Thanks.

								Honza

PS: Sorry for the huge recipient list but I don't really know how to trim it
    down...

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