NFSv4.1: Add a module parameter to set the number of session slots

Add the module parameter 'max_session_slots' to set the initial number
of slots that the NFSv4.1 client will attempt to negotiate with the
server.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index f3f56f4..0b33165 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -72,6 +72,8 @@
 
 #define NFS4_MAX_LOOP_ON_RECOVER (10)
 
+static unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
+
 struct nfs4_opendata;
 static int _nfs4_proc_open(struct nfs4_opendata *data);
 static int _nfs4_recover_proc_open(struct nfs4_opendata *data);
@@ -5245,7 +5247,7 @@
 	args->fc_attrs.max_rqst_sz = mxrqst_sz;
 	args->fc_attrs.max_resp_sz = mxresp_sz;
 	args->fc_attrs.max_ops = NFS4_MAX_OPS;
-	args->fc_attrs.max_reqs = session->clp->cl_rpcclient->cl_xprt->max_reqs;
+	args->fc_attrs.max_reqs = max_session_slots;
 
 	dprintk("%s: Fore Channel : max_rqst_sz=%u max_resp_sz=%u "
 		"max_ops=%u max_reqs=%u\n",
@@ -6390,6 +6392,10 @@
 	NULL
 };
 
+module_param(max_session_slots, ushort, 0644);
+MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
+		"requests the client will negotiate");
+
 /*
  * Local variables:
  *  c-basic-offset: 8