This reverts commit c9af9fb68e.
We need to block and truncate all pages in order to reliably invalidate
them. Otherwise, we could:
- have some uptodate pages in the cache
- queue an invalidate
- write(2) locks some pages
- invalidate_work skips them
- write(2) only overwrites part of the page
- page now dirty and uptodate
-> partial leakage of invalidated data
It's not entirely clear why we started skipping locked pages in the first
place. I just ran this through fsx and didn't see any problems.
Signed-off-by: Sage Weil <sage@newdream.net>