On architectures with hardware broadcasting of TLB invalidation messages
, it makes sense to reduce the range of the mmu_gather structure when
unmapping page ranges based on the dirty address information passed to
tlb_remove_tlb_entry.
arm64 already does this by directly manipulating the start/end fields
of the gather structure, but this confuses the generic code which
does not expect these fields to change and can end up calculating
invalid, negative ranges when forcing a flush in zap_pte_range.
This patch moves the minimal range calculation out of the arm64 code
and into the generic implementation, simplifying zap_pte_range in the
process (which no longer needs to care about start/end, since they will
point to the appropriate ranges already). With the range being tracked
by core code, the need_flush flag is dropped in favour of checking that
the end of the range has actually been set.
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Russell King - ARM Linux <[email protected]>
Cc: Michal Simek <[email protected]>
Acked-by: Linus Torvalds <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Will Deacon
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