tree be15b2e4801c837c5e20d43b8f29a53c0ba1391c
parent 7786fa9ac5366214fb942a9e62c6e46b4272c22c
author Shaohua Li <shaohua.li@intel.com> 1202192973 -0800
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1202233459 -0800

page migraton: handle orphaned pages

Orphaned page might have fs-private metadata, the page is truncated.  As
the page hasn't mapping, page migration refuse to migrate the page.  It
appears the page is only freed in page reclaim and if zone watermark is
low, the page is never freed, as a result migration always fail.  I thought
we could free the metadata so such page can be freed in migration and make
migration more reliable.

[akpm@linux-foundation.org: go direct to try_to_free_buffers()]
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>