[PATCH] Direct Migration V9: Avoid writeback / page_migrate() method

Migrate a page with buffers without requiring writeback

This introduces a new address space operation migratepage() that may be used
by a filesystem to implement its own version of page migration.

A version is provided that migrates buffers attached to pages.  Some
filesystems (ext2, ext3, xfs) are modified to utilize this feature.

The swapper address space operation are modified so that a regular
migrate_page() will occur for anonymous pages without writeback (migrate_pages
forces every anonymous page to have a swap entry).

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/mm/swap_state.c b/mm/swap_state.c
index 7b09ac503fec..db8a3d3e1636 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -27,6 +27,7 @@ static struct address_space_operations swap_aops = {
         .writepage      = swap_writepage,
         .sync_page      = block_sync_page,
         .set_page_dirty = __set_page_dirty_nobuffers,
+        .migratepage    = migrate_page,
 };
 
 static struct backing_dev_info swap_backing_dev_info = {