FOLL_FORCE is really only for ptrace access. R/O pinning a page is
supposed to fail if the VMA misses proper access permissions (no VM_READ).

Let's just remove FOLL_FORCE usage here; there would have to be a pretty
good reason to allow arbitrary drivers to R/O pin pages in a PROT_NONE
VMA. Most probably, FOLL_FORCE usage is just some legacy leftover.

Link: https://lkml.kernel.org/r/20221116102659.70287-16-david@redhat.comSigned-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Andy Walls <awalls@md.metrocast.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>