[RFC][patch 6/12][CFQ-cgroup] Add cfq optional operation framework

["Satoshi UCHIDA" <s-uchida@ap.jp.nec.com>]

This patch creates a cfq optional operations framework.
This framework defines specific functions for expanding CFQ.

      Signed-off-by: Satoshi UCHIDA <uchida@ap.jp.nec.com>

---
 block/cfq-cgroup.c          |    4 ++++
 block/cfq-iosched.c         |    5 +++++
 include/linux/cfq-iosched.h |    6 ++++++
 3 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/block/cfq-cgroup.c b/block/cfq-cgroup.c
index 378a23d..bcb55c8 100644
--- a/block/cfq-cgroup.c
+++ b/block/cfq-cgroup.c
@@ -151,3 +151,7 @@ struct cgroup_subsys cfq_subsys = {
 	.subsys_id = cfq_subsys_id,
 	.populate = cfq_cgroup_populate,
 };
+
+
+struct cfq_ops opt = {
+};
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index aaf5d7e..245c252 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -2233,6 +2233,11 @@ static void __exit cfq_exit(void)
 module_init(cfq_init);
 module_exit(cfq_exit);
 
+#ifndef CONFIG_CGROUP_CFQ
+struct cfq_ops opt = {
+};
+#endif
+
 MODULE_AUTHOR("Jens Axboe");
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Completely Fair Queueing IO scheduler");
diff --git a/include/linux/cfq-iosched.h b/include/linux/cfq-iosched.h
index 035bfc4..9287da1 100644
--- a/include/linux/cfq-iosched.h
+++ b/include/linux/cfq-iosched.h
@@ -87,4 +87,10 @@ static inline struct request_queue * __cfq_container_of_queue(struct work_struct
 	return cfqd->cfq_driv_d.queue;
 };
 
+struct cfq_ops
+{
+};
+
+extern struct cfq_ops opt;
+
 #endif  /* _LINUX_CFQ_IOSCHED_H */
-- 
1.5.4.1