block: move some wbt helpers to blk-wbt.c

A few helpers are only used from blk-wbt.c, so move them there, and put
wbt_track() behind the CONFIG_BLK_WBT typedef. This is in preparation
for changing how the wbt flags are tracked.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-wbt.h b/block/blk-wbt.h
index d6a125e..5bdae20 100644
--- a/block/blk-wbt.h
+++ b/block/blk-wbt.h
@@ -35,31 +35,6 @@ enum {
 	WBT_STATE_ON_MANUAL	= 2,
 };
 
-static inline void wbt_clear_state(struct blk_issue_stat *stat)
-{
-	stat->stat &= ~BLK_STAT_RES_MASK;
-}
-
-static inline enum wbt_flags wbt_stat_to_mask(struct blk_issue_stat *stat)
-{
-	return (stat->stat & BLK_STAT_RES_MASK) >> BLK_STAT_RES_SHIFT;
-}
-
-static inline void wbt_track(struct blk_issue_stat *stat, enum wbt_flags wb_acct)
-{
-	stat->stat |= ((u64) wb_acct) << BLK_STAT_RES_SHIFT;
-}
-
-static inline bool wbt_is_tracked(struct blk_issue_stat *stat)
-{
-	return (stat->stat >> BLK_STAT_RES_SHIFT) & WBT_TRACKED;
-}
-
-static inline bool wbt_is_read(struct blk_issue_stat *stat)
-{
-	return (stat->stat >> BLK_STAT_RES_SHIFT) & WBT_READ;
-}
-
 struct rq_wait {
 	wait_queue_head_t wait;
 	atomic_t inflight;
@@ -113,6 +88,11 @@ static inline unsigned int wbt_inflight(struct rq_wb *rwb)
 
 #ifdef CONFIG_BLK_WBT
 
+static inline void wbt_track(struct blk_issue_stat *stat, enum wbt_flags flags)
+{
+	stat->stat |= ((u64)flags) << BLK_STAT_RES_SHIFT;
+}
+
 void __wbt_done(struct rq_wb *, enum wbt_flags);
 void wbt_done(struct rq_wb *, struct blk_issue_stat *);
 enum wbt_flags wbt_wait(struct rq_wb *, struct bio *, spinlock_t *);
@@ -131,6 +111,9 @@ u64 wbt_default_latency_nsec(struct request_queue *);
 
 #else
 
+static inline void wbt_track(struct blk_issue_stat *stat, enum wbt_flags flags)
+{
+}
 static inline void __wbt_done(struct rq_wb *rwb, enum wbt_flags flags)
 {
 }