Now, VM has a feature to migrate non-lru movable pages so
balloon doesn't need custom migration hooks in migrate.c
and compaction.c. Instead, this patch implements
page->mapping->a_ops->{isolate|migrate|putback} functions.
With that, we could remove hooks for ballooning in general
migration functions and make balloon compaction simple.
Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Rafael Aquini <aquini@xxxxxxxxxx>
Cc: Konstantin Khlebnikov <koct9i@xxxxxxxxx>
Signed-off-by: Gioh Kim <gi-oh.kim@xxxxxxxxxxxxxxxx>
Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>