migrate_pages: split unmap_and_move() to _unmap() and _move()

This is a preparation patch to batch the folio unmapping and moving.

In this patch, unmap_and_move() is split to migrate_folio_unmap() and
migrate_folio_move().  So, we can batch _unmap() and _move() in different
loops later.  To pass some information between unmap and move, the
original unused dst->mapping and dst->private are used.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: "Huang, Ying" <[email protected]>
Reviewed-by: Baolin Wang <[email protected]>
Reviewed-by: Xin Hao <[email protected]>
Cc: Zi Yan <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Bharata B Rao <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Mike Kravetz <[email protected]>
Cc: Hyeonggon Yoo <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions