NFS: Add nfs_client behavior flags

"noresvport" and "discrtry" can be passed to nfs_create_rpc_client()
by setting flags in the passed-in nfs_client. This change makes it
easy to add new flags.

Note that these settings are now "sticky" over the lifetime of a
struct nfs_client, and may even be copied when an nfs_client is
cloned.

Signed-off-by: Chuck Lever <[e-mail]>
Signed-off-by: Trond Myklebust <[e-mail]>

fs/nfs/client.c

···
 #endif  /* CONFIG_NFS_V3_ACL */
 
 struct nfs_client_initdata {
+	unsigned long init_flags;
 	const char *hostname;
 	const struct sockaddr *addr;
 	size_t addrlen;
···
 nfs_get_client(const struct nfs_client_initdata *cl_init,
 	       const struct rpc_timeout *timeparms,
 	       const char *ip_addr,
-	       rpc_authflavor_t authflavour,
-	       int noresvport)
+	       rpc_authflavor_t authflavour)
 {
 	struct nfs_client *clp, *new = NULL;
 	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
···
 		if (new) {
 			list_add(&new->cl_share_link, &nn->nfs_client_list);
 			spin_unlock(&nn->nfs_client_lock);
+			new->cl_flags = cl_init->init_flags;
 			return cl_init->rpc_ops->init_client(new,
 						timeparms, ip_addr,
-						authflavour, noresvport);
+						authflavour);
 		}
 
 		spin_unlock(&nn->nfs_client_lock);
···
  */
 static int nfs_create_rpc_client(struct nfs_client *clp,
 				 const struct rpc_timeout *timeparms,
-				 rpc_authflavor_t flavor,
-				 int discrtry, int noresvport)
+				 rpc_authflavor_t flavor)
 {
 	struct rpc_clnt		*clnt = NULL;
 	struct rpc_create_args args = {
···
 		.authflavor	= flavor,
 	};
 
-	if (discrtry)
+	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
-	if (noresvport)
+	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
 
 	if (!IS_ERR(clp->cl_rpcclient))
···
  * @timeparms: timeout parameters for underlying RPC transport
  * @ip_addr: IP presentation address (not used)
  * @authflavor: authentication flavor for underlying RPC transport
- * @noresvport: set if RPC transport can use an ephemeral source port
  *
  * Returns pointer to an NFS client, or an ERR_PTR value.
  */
 struct nfs_client *nfs_init_client(struct nfs_client *clp,
 		    const struct rpc_timeout *timeparms,
-		    const char *ip_addr, rpc_authflavor_t authflavour,
-		    int noresvport)
+		    const char *ip_addr, rpc_authflavor_t authflavour)
 {
 	int error;
 
···
 	 * Create a client RPC handle for doing FSSTAT with UNIX auth only
 	 * - RFC 2623, sec 2.3.2
 	 */
-	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX,
-				      0, noresvport);
+	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
 	if (error < 0)
 		goto error;
 	nfs_mark_client_ready(clp, NFS_CS_READY);
···
 
 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 			data->timeo, data->retrans);
+	if (data->flags & NFS_MOUNT_NORESVPORT)
+		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 
 	/* Allocate or find a client reference we can use */
-	clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX,
-			     data->flags & NFS_MOUNT_NORESVPORT);
+	clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX);
 	if (IS_ERR(clp)) {
 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
 		return PTR_ERR(clp);
···
  * @timeparms: timeout parameters for underlying RPC transport
  * @ip_addr: callback IP address in presentation format
  * @authflavor: authentication flavor for underlying RPC transport
- * @noresvport: set if RPC transport can use an ephemeral source port
  *
  * Returns pointer to an NFS client, or an ERR_PTR value.
  */
 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 				    const struct rpc_timeout *timeparms,
 				    const char *ip_addr,
-				    rpc_authflavor_t authflavour,
-				    int noresvport)
+				    rpc_authflavor_t authflavour)
 {
 	char buf[INET6_ADDRSTRLEN + 1];
 	int error;
···
 	/* Check NFS protocol revision and initialize RPC op vector */
 	clp->rpc_ops = &nfs_v4_clientops;
 
-	error = nfs_create_rpc_client(clp, timeparms, authflavour,
-				      1, noresvport);
+	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
+	error = nfs_create_rpc_client(clp, timeparms, authflavour);
 	if (error < 0)
 		goto error;
 
···
 
 	dprintk("--> nfs4_set_client()\n");
 
+	if (server->flags & NFS_MOUNT_NORESVPORT)
+		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
+
 	/* Allocate or find a client reference we can use */
-	clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour,
-			     server->flags & NFS_MOUNT_NORESVPORT);
+	clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
 	if (IS_ERR(clp)) {
 		error = PTR_ERR(clp);
 		goto error;
···
 	 */
 	nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 	clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
-			     mds_clp->cl_rpcclient->cl_auth->au_flavor, 0);
+			     mds_clp->cl_rpcclient->cl_auth->au_flavor);
 
 	dprintk("<-- %s %p\n", __func__, clp);
 	return clp;

fs/nfs/internal.h

···
 void nfs_close_context(struct nfs_open_context *ctx, int is_sync);
 extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
 			   const struct rpc_timeout *timeparms,
-			   const char *ip_addr, rpc_authflavor_t authflavour,
-			   int noresvport);
+			   const char *ip_addr, rpc_authflavor_t authflavour);
 
 /* dir.c */
 extern int nfs_access_cache_shrinker(struct shrinker *shrink,
···
 extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 			    const struct rpc_timeout *timeparms,
 			    const char *ip_addr,
-			    rpc_authflavor_t authflavour,
-			    int noresvport);
+			    rpc_authflavor_t authflavour);
 extern int _nfs4_call_sync(struct rpc_clnt *clnt,
 			   struct nfs_server *server,
 			   struct rpc_message *msg,

include/linux/nfs_fs_sb.h

···
 #define NFS_CS_RENEWD		3		/* - renewd started */
 #define NFS_CS_STOP_RENEW	4		/* no more state to renew */
 #define NFS_CS_CHECK_LEASE_TIME	5		/* need to check lease time */
+	unsigned long		cl_flags;	/* behavior switches */
+#define NFS_CS_NORESVPORT	0		/* - use ephemeral src port */
+#define NFS_CS_DISCRTRY		1		/* - disconnect on RPC retry */
 	struct sockaddr_storage	cl_addr;	/* server identifier */
 	size_t			cl_addrlen;
 	char *			cl_hostname;	/* hostname of server */

include/linux/nfs_xdr.h

···
 				struct iattr *iattr);
 	struct nfs_client *
 		(*init_client) (struct nfs_client *, const struct rpc_timeout *,
-				const char *, rpc_authflavor_t, int);
+				const char *, rpc_authflavor_t);
 };
 
 /*