diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c
index f1b9be6..cc9bd11 100644
--- a/sys/kern/vfs_bio.c
+++ b/sys/kern/vfs_bio.c
@@ -557,6 +557,7 @@ bufinit(void)
 		bp->b_qindex = QUEUE_EMPTY;
 		bp->b_vflags = 0;
 		bp->b_xflags = 0;
+		bp->b_waiters = 0;
 		LIST_INIT(&bp->b_dep);
 		BUF_LOCKINIT(bp);
 		TAILQ_INSERT_TAIL(&bufqueues[QUEUE_EMPTY], bp, b_freelist);
@@ -1195,7 +1196,7 @@ brelse(struct buf *bp)
 			if (bp->b_bufsize)
 				allocbuf(bp, 0);
 			if (bp->b_vp)
-				brelvp(bp);
+				(void) brelvp(bp);
 		}
 	}
 
@@ -1337,7 +1338,7 @@ brelse(struct buf *bp)
 		if (bp->b_bufsize != 0)
 			allocbuf(bp, 0);
 		if (bp->b_vp != NULL)
-			brelvp(bp);
+			(void) brelvp(bp);
 	}
 			
 	if (BUF_LOCKRECURSED(bp)) {
@@ -1401,7 +1402,7 @@ brelse(struct buf *bp)
 		if (bp->b_flags & B_DELWRI)
 			bundirty(bp);
 		if (bp->b_vp)
-			brelvp(bp);
+			(void) brelvp(bp);
 	}
 
 	/*
@@ -1569,7 +1570,7 @@ vfs_vmio_release(struct buf *bp)
 	bp->b_npages = 0;
 	bp->b_flags &= ~B_VMIO;
 	if (bp->b_vp)
-		brelvp(bp);
+		(void) brelvp(bp);
 }
 
 /*
@@ -1706,6 +1707,7 @@ getnewbuf(int slpflag, int slptimeo, int size, int maxsize)
 	struct buf *nbp;
 	int defrag = 0;
 	int nqindex;
+	int waiters = 0;
 	static int flushingbufs;
 
 	/*
@@ -1844,7 +1846,7 @@ restart:
 				vfs_vmio_release(bp);
 			}
 			if (bp->b_vp)
-				brelvp(bp);
+				waiters = brelvp(bp);
 		}
 
 		/*
@@ -1913,7 +1915,7 @@ restart:
 		 * Notify any waiters for the buffer lock about
 		 * identity change by freeing the buffer.
 		 */
-		if (qindex == QUEUE_CLEAN && BUF_LOCKWAITERS(bp) > 0) {
+		if (qindex == QUEUE_CLEAN && waiters > 0) {
 			bp->b_flags |= B_INVAL;
 			bfreekva(bp);
 			brelse(bp);
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 176be13..f6e1a59 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -1525,11 +1525,12 @@ bgetvp(struct vnode *vp, struct buf *bp)
 /*
  * Disassociate a buffer from a vnode.
  */
-void
+int
 brelvp(struct buf *bp)
 {
 	struct bufobj *bo;
 	struct vnode *vp;
+	int waiters;
 
 	CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
 	KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
@@ -1554,7 +1555,10 @@ brelvp(struct buf *bp)
 	bp->b_flags &= ~B_NEEDSGIANT;
 	bp->b_vp = NULL;
 	bp->b_bufobj = NULL;
+	waiters = bp->b_waiters;
 	vdropl(vp);
+
+	return (waiters);
 }
 
 /*
diff --git a/sys/sys/buf.h b/sys/sys/buf.h
index 486c73c..58e5ad7 100644
--- a/sys/sys/buf.h
+++ b/sys/sys/buf.h
@@ -139,6 +139,7 @@ struct buf {
 	void	*b_fsprivate2;
 	void	*b_fsprivate3;
 	int	b_pin_count;
+	int	b_waiters;		/* (V) waiters counter */
 };
 
 #define b_object	b_bufobj->bo_object
@@ -266,15 +267,41 @@ extern const char *buf_wmesg;		/* Default buffer lock message */
  *
  * Get a lock sleeping non-interruptably until it becomes available.
  */
-#define	BUF_LOCK(bp, locktype, interlock)				\
-	(lockmgr(&(bp)->b_lock, (locktype), (interlock)))
+static __inline int
+BUF_LOCK(struct buf *bp, int locktype, struct mtx *interlock);
+static __inline int
+BUF_LOCK(struct buf *bp, int locktype, struct mtx *interlock)
+{
+	int res;
+
+	if (locktype & LK_INTERLOCK)
+		bp->b_waiters++;
+	res = lockmgr(&bp->b_lock, locktype, interlock);
+	if (locktype & LK_INTERLOCK)
+		bp->b_waiters--;
+	return (res);
+}
 
 /*
  * Get a lock sleeping with specified interruptably and timeout.
  */
-#define	BUF_TIMELOCK(bp, locktype, interlock, wmesg, catch, timo)	\
-	(lockmgr_args(&(bp)->b_lock, (locktype) | LK_TIMELOCK,		\
-	    (interlock), (wmesg), (PRIBIO + 4) | (catch), (timo)))
+static __inline int
+BUF_TIMELOCK(struct buf *bp, int locktype, struct mtx *interlock,
+    const char *wmesg, int catch, int timo);
+static __inline int
+BUF_TIMELOCK(struct buf *bp, int locktype, struct mtx *interlock,
+    const char *wmesg, int catch, int timo)
+{
+	int res;
+
+	if (locktype & LK_INTERLOCK)
+		bp->b_waiters++;
+	res = lockmgr_args(&bp->b_lock, locktype | LK_TIMELOCK, interlock,
+	    wmesg, (PRIBIO + 4) | catch, timo);
+	if (locktype & LK_INTERLOCK)
+		bp->b_waiters--;
+	return (res);
+}
 
 /*
  * Release a lock. Only the acquiring process may free the lock unless
@@ -351,16 +378,6 @@ BUF_KERNPROC(struct buf *bp)
 }
 #endif
 
-/*
- * Find out the number of waiters on a lock.
- */
-static __inline int BUF_LOCKWAITERS(struct buf *);
-static __inline int
-BUF_LOCKWAITERS(struct buf *bp)
-{
-	return (lockwaiters(&bp->b_lock));
-}
-
 #endif /* _KERNEL */
 
 struct buf_queue_head {
@@ -516,7 +533,7 @@ void	vfs_unbusy_pages(struct buf *);
 int	vmapbuf(struct buf *);
 void	vunmapbuf(struct buf *);
 void	relpbuf(struct buf *, int *);
-void	brelvp(struct buf *);
+int	brelvp(struct buf *);
 void	bgetvp(struct vnode *, struct buf *);
 void	pbgetbo(struct bufobj *bo, struct buf *bp);
 void	pbgetvp(struct vnode *, struct buf *);