SUNRPC: Relocate svc_free_res_pages()

Clean-up: There doesn't seem to be a reason why this function is
stuck in a header. One thing it prevents is the convenient addition
of tracing. Moving it to a source file also makes the rq_respages
clean-up logic easier to find.
Reviewed-by: Calum Mackay <calum.mackay@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

include/linux/sunrpc/svc.h

@@ -309,17 +309,6 @@ static inline struct sockaddr *svc_daddr(const struct svc_rqst *rqst)
 	return (struct sockaddr *) &rqst->rq_daddr;
 }
 
-static inline void svc_free_res_pages(struct svc_rqst *rqstp)
-{
-	while (rqstp->rq_next_page != rqstp->rq_respages) {
-		struct page **pp = --rqstp->rq_next_page;
-		if (*pp) {
-			put_page(*pp);
-			*pp = NULL;
-		}
-	}
-}
-
 struct svc_deferred_req {
 	u32			prot;	/* protocol (UDP or TCP) */
 	struct svc_xprt		*xprt;
@@ -424,6 +413,7 @@ struct svc_rqst *svc_rqst_alloc(struct svc_serv *serv,
 					struct svc_pool *pool, int node);
 bool		   svc_rqst_replace_page(struct svc_rqst *rqstp,
 					 struct page *page);
+void		   svc_rqst_release_pages(struct svc_rqst *rqstp);
 void		   svc_rqst_free(struct svc_rqst *);
 void		   svc_exit_thread(struct svc_rqst *);
 struct svc_serv *  svc_create_pooled(struct svc_program *, unsigned int,

net/sunrpc/svc.c

@@ -869,6 +869,25 @@ bool svc_rqst_replace_page(struct svc_rqst *rqstp, struct page *page)
 }
 EXPORT_SYMBOL_GPL(svc_rqst_replace_page);
 
+/**
+ * svc_rqst_release_pages - Release Reply buffer pages
+ * @rqstp: RPC transaction context
+ *
+ * Release response pages that might still be in flight after
+ * svc_send, and any spliced filesystem-owned pages.
+ */
+void svc_rqst_release_pages(struct svc_rqst *rqstp)
+{
+	while (rqstp->rq_next_page != rqstp->rq_respages) {
+		struct page **pp = --rqstp->rq_next_page;
+
+		if (*pp) {
+			put_page(*pp);
+			*pp = NULL;
+		}
+	}
+}
+
 /*
  * Called from a server thread as it's exiting. Caller must hold the "service
  * mutex" for the service.

net/sunrpc/svc_xprt.c

@@ -542,7 +542,7 @@ static void svc_xprt_release(struct svc_rqst *rqstp)
 	rqstp->rq_deferred = NULL;
 
 	pagevec_release(&rqstp->rq_pvec);
-	svc_free_res_pages(rqstp);
+	svc_rqst_release_pages(rqstp);
 	rqstp->rq_res.page_len = 0;
 	rqstp->rq_res.page_base = 0;