SUNRPC: Allow rpc_create() to request that TCP slots be unlimited

This is mainly for use by NFSv4.1, where the session negotiation
ultimately wants to decide how many RPC slots we can fill.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 11 insertions, 1 deletions

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 2cf4ffaa3cd4..e7d492ce7c18 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -124,6 +124,7 @@ struct rpc_create_args {
 #define RPC_CLNT_CREATE_NOPING          (1UL << 4)
 #define RPC_CLNT_CREATE_DISCRTRY        (1UL << 5)
 #define RPC_CLNT_CREATE_QUIET           (1UL << 6)
+#define RPC_CLNT_CREATE_INFINITE_SLOTS  (1UL << 7)
 
 struct rpc_clnt *rpc_create(struct rpc_create_args *args);
 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *,
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 12815f66a9c4..ff5392421cb2 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -255,6 +255,8 @@ static inline int bc_prealloc(struct rpc_rqst *req)
 }
 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
 
+#define XPRT_CREATE_INFINITE_SLOTS      (1U)
+
 struct xprt_create {
         int                     ident;          /* XPRT_TRANSPORT identifier */
         struct net *            net;
@@ -263,6 +265,7 @@ struct xprt_create {
         size_t                  addrlen;
         const char              *servername;
         struct svc_xprt         *bc_xprt;       /* NFSv4.1 backchannel */
+        unsigned int            flags;
 };
 
 struct xprt_class {
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index a80ee9b80dcf..651245aa829a 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -414,6 +414,8 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args)
         };
         char servername[48];
 
+        if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
+                xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
         /*
          * If the caller chooses not to specify a hostname, whip
          * up a string representation of the passed-in address.
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 3081620cb02c..726e702b7a29 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -2762,9 +2762,13 @@ static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
         struct rpc_xprt *xprt;
         struct sock_xprt *transport;
         struct rpc_xprt *ret;
+        unsigned int max_slot_table_size = xprt_max_tcp_slot_table_entries;
+
+        if (args->flags & XPRT_CREATE_INFINITE_SLOTS)
+                max_slot_table_size = RPC_MAX_SLOT_TABLE_LIMIT;
 
         xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries,
-                        xprt_max_tcp_slot_table_entries);
+                        max_slot_table_size);
         if (IS_ERR(xprt))
                 return xprt;
         transport = container_of(xprt, struct sock_xprt, xprt);