Use the general page fault accounting by passing regs into
handle_mm_fault().  It naturally solve the issue of multiple page fault
accounting when page fault retry happened.  To do this, we pass pt_regs
pointer into __do_page_fault().
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: http://lkml.kernel.org/r/20200707225021.200906-6-peterx@redhat.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>