Provide a generic tlb_flush() implementation that relies on
flush_tlb_range(). This is a little awkward because flush_tlb_range()
assumes a VMA for range invalidation, but we no longer have one.

Audit of all flush_tlb_range() implementations shows only vma->vm_mm
and vma->vm_flags are used, and of the latter only VM_EXEC (I-TLB
invalidates) and VM_HUGETLB (large TLB invalidate) are used.

Therefore, track VM_EXEC and VM_HUGETLB in two more bits, and create a
'fake' VMA.

This allows architectures that have a reasonably efficient
flush_tlb_range() to not require any additional effort.

No change in behavior intended.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>