nilfs2: use list_splice_tail or list_splice_tail_init

This applies list_splice_tail (or list_splice_tail_init) operation
instead of list_splice (or list_splice_init, respectively) to append a
new list to tail of an existing list.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

fs/nilfs2/btree.c

@@ -2018,7 +2018,7 @@ static void nilfs_btree_lookup_dirty_buffers(struct nilfs_bmap *bmap,
 	for (level = NILFS_BTREE_LEVEL_NODE_MIN;
 	     level < NILFS_BTREE_LEVEL_MAX;
 	     level++)
-		list_splice(&lists[level], listp->prev);
+		list_splice_tail(&lists[level], listp);
 }
 
 static int nilfs_btree_assign_p(struct nilfs_btree *btree,

fs/nilfs2/recovery.c

@@ -925,7 +925,7 @@ int nilfs_search_super_root(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi,
 
  super_root_found:
 	/* Updating pointers relating to the latest checkpoint */
-	list_splice(&segments, ri->ri_used_segments.prev);
+	list_splice_tail(&segments, &ri->ri_used_segments);
 	nilfs->ns_last_pseg = sr_pseg_start;
 	nilfs->ns_last_seq = nilfs->ns_seg_seq;
 	nilfs->ns_last_cno = ri->ri_cno;

fs/nilfs2/segment.c

@@ -1363,7 +1363,7 @@ static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci,
 		list_add_tail(&segbuf->sb_list, &list);
 		prev = segbuf;
 	}
-	list_splice(&list, sci->sc_segbufs.prev);
+	list_splice_tail(&list, &sci->sc_segbufs);
 	return 0;
 
  failed_segbuf:
@@ -2532,7 +2532,7 @@ int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
 
 	sci->sc_freesegs = kbufs[4];
 	sci->sc_nfreesegs = argv[4].v_nmembs;
-	list_splice_init(&nilfs->ns_gc_inodes, sci->sc_gc_inodes.prev);
+	list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes);
 
 	for (;;) {
 		nilfs_segctor_accept(sci, &req);