nfs41 do not allocate unused back channel pages
Signed-off-by: Andy Adamson <andros@netapp.com>
[Trond.Myklebust@netapp.com: moved definition of svc_is_backchannel()
into include/linux/sunrpc/bc_xprt.h.]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/sunrpc/bc_xprt.h b/include/linux/sunrpc/bc_xprt.h
index 6508f0d..d7152b4 100644
--- a/include/linux/sunrpc/bc_xprt.h
+++ b/include/linux/sunrpc/bc_xprt.h
@@ -38,12 +38,27 @@
void xprt_destroy_backchannel(struct rpc_xprt *, int max_reqs);
void bc_release_request(struct rpc_task *);
int bc_send(struct rpc_rqst *req);
+
+/*
+ * Determine if a shared backchannel is in use
+ */
+static inline int svc_is_backchannel(const struct svc_rqst *rqstp)
+{
+ if (rqstp->rq_server->bc_xprt)
+ return 1;
+ return 0;
+}
#else /* CONFIG_NFS_V4_1 */
static inline int xprt_setup_backchannel(struct rpc_xprt *xprt,
unsigned int min_reqs)
{
return 0;
}
+
+static inline int svc_is_backchannel(const struct svc_rqst *rqstp)
+{
+ return 0;
+}
#endif /* CONFIG_NFS_V4_1 */
#endif /* _LINUX_SUNRPC_BC_XPRT_H */
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 538ca43..6dcf8c9 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -506,6 +506,10 @@
{
unsigned int pages, arghi;
+ /* bc_xprt uses fore channel allocated buffers */
+ if (svc_is_backchannel(rqstp))
+ return 1;
+
pages = size / PAGE_SIZE + 1; /* extra page as we hold both request and reply.
* We assume one is at most one page
*/