nilfs2: get rid of private page allocator

Previously, nilfs was cloning pages for mmapped region to freeze their
data and ensure consistency of checksum during writeback cycles.  A
private page allocator was used for this page cloning.  But, we no
longer need to do that since clear_page_dirty_for_io function sets up
pte so that vm_ops->page_mkwrite function is called right before the
mmapped pages are modified and nilfs_page_mkwrite function can safely
wait for the pages to be written back to disk.

So, this stops making a copy of mmapped pages during writeback, and
eliminates the private page allocation and deallocation functions from
nilfs.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

1 files changed, 0 insertions, 2 deletions

diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h
index 6c02a86..38a1d00 100644
--- a/fs/nilfs2/segment.h
+++ b/fs/nilfs2/segment.h
@@ -92,7 +92,6 @@ struct nilfs_segsum_pointer {
  * @sc_nblk_inc: Block count of current generation
  * @sc_dirty_files: List of files to be written
  * @sc_gc_inodes: List of GC inodes having blocks to be written
- * @sc_copied_buffers: List of copied buffers (buffer heads) to freeze data
  * @sc_freesegs: array of segment numbers to be freed
  * @sc_nfreesegs: number of segments on @sc_freesegs
  * @sc_dsync_inode: inode whose data pages are written for a sync operation
@@ -136,7 +135,6 @@ struct nilfs_sc_info {
 
 	struct list_head	sc_dirty_files;
 	struct list_head	sc_gc_inodes;
-	struct list_head	sc_copied_buffers;
 
 	__u64		       *sc_freesegs;
 	size_t			sc_nfreesegs;