[RFC V5 13/16] blk-wbt: move cache setting to rq_qos_setting_changed()

["Wang Jianchao (Kuaishou)" <jianchao.wan9@xxxxxxxxx>]

Move cache setting to rq_qos_setting_changed then we can avoid
to export a standalone wbt interface to blk_queue_write_cache().

Signed-off-by: Wang Jianchao (Kuaishou) <jianchao.wan9@xxxxxxxxx>
---
 block/blk-settings.c |  4 ++--
 block/blk-wbt.c      | 13 ++-----------
 block/blk-wbt.h      |  7 -------
 3 files changed, 4 insertions(+), 20 deletions(-)

diff --git a/block/blk-settings.c b/block/blk-settings.c
index bceb1925e978..124bf5cc623f 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -16,7 +16,7 @@
 #include <linux/dma-mapping.h>
 
 #include "blk.h"
-#include "blk-wbt.h"
+#include "blk-rq-qos.h"
 
 void blk_queue_rq_timeout(struct request_queue *q, unsigned int timeout)
 {
@@ -800,7 +800,7 @@ void blk_queue_write_cache(struct request_queue *q, bool wc, bool fua)
 	else
 		blk_queue_flag_clear(QUEUE_FLAG_FUA, q);
 
-	wbt_set_write_cache(q, test_bit(QUEUE_FLAG_WC, &q->queue_flags));
+	rq_qos_setting_changed(q);
 }
 EXPORT_SYMBOL_GPL(blk_queue_write_cache);
 
diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index 3a3a683009c4..83e05417e25f 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -615,16 +615,6 @@ static void wbt_requeue(struct rq_qos *rqos, struct request *rq)
 	}
 }
 
-void wbt_set_write_cache(struct request_queue *q, bool write_cache_on)
-{
-	struct rq_qos *rqos = wbt_rq_qos(q);
-
-	if (rqos) {
-		RQWB(rqos)->wc = write_cache_on;
-		rq_qos_put(rqos);
-	}
-}
-
 static u64 wbt_default_latency_nsec(struct request_queue *q)
 {
 	/*
@@ -656,6 +646,7 @@ static void wbt_setting_changed(struct rq_qos *rqos)
 		RQWB(rqos)->rq_depth.queue_depth = blk_queue_depth(rqos->q);
 		wbt_update_limits(RQWB(rqos));
 	}
+	RQWB(rqos)->wc = test_bit(QUEUE_FLAG_WC, &rqos->q->queue_flags);
 }
 
 static ssize_t wbt_lat_show(struct request_queue *q, char *page)
@@ -844,7 +835,7 @@ static int wbt_init(struct request_queue *q)
 	rwb->min_lat_nsec = wbt_default_latency_nsec(q);
 
 	wbt_setting_changed(&rwb->rqos);
-	wbt_set_write_cache(q, test_bit(QUEUE_FLAG_WC, &q->queue_flags));
+	rwb->wc = test_bit(QUEUE_FLAG_WC, &q->queue_flags);
 
 	ret = sysfs_create_file(&q->kobj, &wbt_attr.attr);
 	if (ret < 0)
diff --git a/block/blk-wbt.h b/block/blk-wbt.h
index fe26f78390bd..eb837dfd0ace 100644
--- a/block/blk-wbt.h
+++ b/block/blk-wbt.h
@@ -74,17 +74,10 @@ static inline unsigned int wbt_inflight(struct rq_wb *rwb)
 }
 
 #ifdef CONFIG_BLK_WBT
-
-void wbt_set_write_cache(struct request_queue *, bool);
-
 #else
-
 static inline void wbt_track(struct request *rq, enum wbt_flags flags)
 {
 }
-static inline void wbt_set_write_cache(struct request_queue *q, bool wc)
-{
-}
 #endif /* CONFIG_BLK_WBT */
 
 #endif
-- 
2.17.1