cleanup
Revert "mm: allow for outstanding swap writeback accounting"

This reverts commit f6e8d20491d67d647b8d130a613a4a7540c96a25.
Revert "mm: break up swap_writepage() for frontswap backends"

This reverts commit cd39452db8407464468074fb2949c390a5ccefcd.
Revert "mm: remove compressed copy from zram in-memory"

This reverts commit e310fd68eb693bb0bca25097f83cf15e0dcbe061.

Conflicts:
	mm/page_io.c
major cleanup