nfsd41: sunrpc: add new xprt class for nfsv4.1 backchannel

[sunrpc: change idle timeout value for the backchannel]
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 3d02558..8ed9642 100644 (file)
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -114,6 +114,7 @@ struct rpc_create_args {
        rpc_authflavor_t        authflavor;
        unsigned long           flags;
        char                    *client_name;
+       struct svc_xprt         *bc_xprt;       /* NFSv4.1 backchannel */
 };
 
 /* Values for "flags" field */

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 228d694..6f9457a 100644 (file)
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -124,6 +124,23 @@ struct rpc_xprt_ops {
        void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
 };
 
+/*
+ * RPC transport identifiers
+ *
+ * To preserve compatibility with the historical use of raw IP protocol
+ * id's for transport selection, UDP and TCP identifiers are specified
+ * with the previous values. No such restriction exists for new transports,
+ * except that they may not collide with these values (17 and 6,
+ * respectively).
+ */
+#define XPRT_TRANSPORT_BC       (1 << 31)
+enum xprt_transports {
+       XPRT_TRANSPORT_UDP      = IPPROTO_UDP,
+       XPRT_TRANSPORT_TCP      = IPPROTO_TCP,
+       XPRT_TRANSPORT_BC_TCP   = IPPROTO_TCP | XPRT_TRANSPORT_BC,
+       XPRT_TRANSPORT_RDMA     = 256
+};
+
 struct rpc_xprt {
        struct kref             kref;           /* Reference count */
        struct rpc_xprt_ops *   ops;            /* transport methods */
@@ -232,6 +249,7 @@ struct xprt_create {
        struct sockaddr *       srcaddr;        /* optional local address */
        struct sockaddr *       dstaddr;        /* remote peer address */
        size_t                  addrlen;
+       struct svc_xprt         *bc_xprt;       /* NFSv4.1 backchannel */
 };
 
 struct xprt_class {

diff --git a/include/linux/sunrpc/xprtrdma.h b/include/linux/sunrpc/xprtrdma.h
index 54a379c..c2f04e1 100644 (file)
--- a/include/linux/sunrpc/xprtrdma.h
+++ b/include/linux/sunrpc/xprtrdma.h
@@ -41,11 +41,6 @@
 #define _LINUX_SUNRPC_XPRTRDMA_H
 
 /*
- * RPC transport identifier for RDMA
- */
-#define XPRT_TRANSPORT_RDMA    256
-
-/*
  * rpcbind (v3+) RDMA netid.
  */
 #define RPCBIND_NETID_RDMA     "rdma"

diff --git a/include/linux/sunrpc/xprtsock.h b/include/linux/sunrpc/xprtsock.h
index c2a46c4..3f14a02 100644 (file)
--- a/include/linux/sunrpc/xprtsock.h
+++ b/include/linux/sunrpc/xprtsock.h
@@ -13,17 +13,6 @@ int          init_socket_xprt(void);
 void           cleanup_socket_xprt(void);
 
 /*
- * RPC transport identifiers for UDP, TCP
- *
- * To preserve compatibility with the historical use of raw IP protocol
- * id's for transport selection, these are specified with the previous
- * values. No such restriction exists for new transports, except that
- * they may not collide with these values (17 and 6, respectively).
- */
-#define XPRT_TRANSPORT_UDP     IPPROTO_UDP
-#define XPRT_TRANSPORT_TCP     IPPROTO_TCP
-
-/*
  * RPC slot table sizes for UDP, TCP transports
  */
 extern unsigned int xprt_udp_slot_table_entries;

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index c1e467e..7389804 100644 (file)
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -288,6 +288,7 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args)
                .srcaddr = args->saddress,
                .dstaddr = args->address,
                .addrlen = args->addrsize,
+               .bc_xprt = args->bc_xprt,
        };
        char servername[48];
 

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index d9a2b81..bee4154 100644 (file)
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -2468,11 +2468,93 @@ static struct rpc_xprt *xs_setup_tcp(struct xprt_create *args)
        return ERR_PTR(-EINVAL);
 }
 
+/**
+ * xs_setup_bc_tcp - Set up transport to use a TCP backchannel socket
+ * @args: rpc transport creation arguments
+ *
+ */
+static struct rpc_xprt *xs_setup_bc_tcp(struct xprt_create *args)
+{
+       struct sockaddr *addr = args->dstaddr;
+       struct rpc_xprt *xprt;
+       struct sock_xprt *transport;
+       struct svc_sock *bc_sock;
+
+       if (!args->bc_xprt)
+               ERR_PTR(-EINVAL);
+
+       xprt = xs_setup_xprt(args, xprt_tcp_slot_table_entries);
+       if (IS_ERR(xprt))
+               return xprt;
+       transport = container_of(xprt, struct sock_xprt, xprt);
+
+       xprt->prot = IPPROTO_TCP;
+       xprt->tsh_size = sizeof(rpc_fraghdr) / sizeof(u32);
+       xprt->max_payload = RPC_MAX_FRAGMENT_SIZE;
+       xprt->timeout = &xs_tcp_default_timeout;
+
+       /* backchannel */
+       xprt_set_bound(xprt);
+       xprt->bind_timeout = 0;
+       xprt->connect_timeout = 0;
+       xprt->reestablish_timeout = 0;
+       xprt->idle_timeout = 0;
+
+       /*
+        * The backchannel uses the same socket connection as the
+        * forechannel
+        */
+       xprt->bc_xprt = args->bc_xprt;
+       bc_sock = container_of(args->bc_xprt, struct svc_sock, sk_xprt);
+       bc_sock->sk_bc_xprt = xprt;
+       transport->sock = bc_sock->sk_sock;
+       transport->inet = bc_sock->sk_sk;
+
+       xprt->ops = &bc_tcp_ops;
+
+       switch (addr->sa_family) {
+       case AF_INET:
+               xs_format_peer_addresses(xprt, "tcp",
+                                        RPCBIND_NETID_TCP);
+               break;
+       case AF_INET6:
+               xs_format_peer_addresses(xprt, "tcp",
+                                  RPCBIND_NETID_TCP6);
+               break;
+       default:
+               kfree(xprt);
+               return ERR_PTR(-EAFNOSUPPORT);
+       }
+
+       if (xprt_bound(xprt))
+               dprintk("RPC:       set up xprt to %s (port %s) via %s\n",
+                               xprt->address_strings[RPC_DISPLAY_ADDR],
+                               xprt->address_strings[RPC_DISPLAY_PORT],
+                               xprt->address_strings[RPC_DISPLAY_PROTO]);
+       else
+               dprintk("RPC:       set up xprt to %s (autobind) via %s\n",
+                               xprt->address_strings[RPC_DISPLAY_ADDR],
+                               xprt->address_strings[RPC_DISPLAY_PROTO]);
+
+       /*
+        * Since we don't want connections for the backchannel, we set
+        * the xprt status to connected
+        */
+       xprt_set_connected(xprt);
+
+
+       if (try_module_get(THIS_MODULE))
+               return xprt;
+       kfree(xprt->slot);
+       kfree(xprt);
+       return ERR_PTR(-EINVAL);
+}
+
 static struct xprt_class       xs_udp_transport = {
        .list           = LIST_HEAD_INIT(xs_udp_transport.list),
        .name           = "udp",
        .owner          = THIS_MODULE,
-       .ident          = IPPROTO_UDP,
+       .ident          = XPRT_TRANSPORT_UDP,
        .setup          = xs_setup_udp,
 };
 
@@ -2480,10 +2562,18 @@ static struct xprt_class        xs_tcp_transport = {
        .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
        .name           = "tcp",
        .owner          = THIS_MODULE,
-       .ident          = IPPROTO_TCP,
+       .ident          = XPRT_TRANSPORT_TCP,
        .setup          = xs_setup_tcp,
 };
 
+static struct xprt_class       xs_bc_tcp_transport = {
+       .list           = LIST_HEAD_INIT(xs_bc_tcp_transport.list),
+       .name           = "tcp NFSv4.1 backchannel",
+       .owner          = THIS_MODULE,
+       .ident          = XPRT_TRANSPORT_BC_TCP,
+       .setup          = xs_setup_bc_tcp,
+};
+
 /**
  * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
  *
@@ -2497,6 +2587,7 @@ int init_socket_xprt(void)
 
        xprt_register_transport(&xs_udp_transport);
        xprt_register_transport(&xs_tcp_transport);
+       xprt_register_transport(&xs_bc_tcp_transport);
 
        return 0;
 }
@@ -2516,6 +2607,7 @@ void cleanup_socket_xprt(void)
 
        xprt_unregister_transport(&xs_udp_transport);
        xprt_unregister_transport(&xs_tcp_transport);
+       xprt_unregister_transport(&xs_bc_tcp_transport);
 }
 
 static int param_set_uint_minmax(const char *val, struct kernel_param *kp,