NFS/SUNRPC: support transport protocol naming

To prepare for including non-sockets-based RPC transports, select
RPC transports by an identifier (to be used in following patches).

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

5 files changed, 19 insertions, 13 deletions

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index d7b8fcd312cc..30b17b3bc1a9 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -187,7 +187,7 @@ struct rpc_xprt {
 };
 
 struct xprt_create {
-        int                     proto;          /* IPPROTO_UDP or IPPROTO_TCP */
+        int                     ident;          /* XPRT_TRANSPORT identifier */
         struct sockaddr *       srcaddr;        /* optional local address */
         struct sockaddr *       dstaddr;        /* remote peer address */
         size_t                  addrlen;
@@ -196,8 +196,7 @@ struct xprt_create {
 
 struct xprt_class {
         struct list_head        list;
-        unsigned short          family;
-        int                     protocol;
+        int                     ident;          /* XPRT_TRANSPORT identifier */
         struct rpc_xprt *       (*setup)(struct xprt_create *);
         struct module           *owner;
         char                    name[32];
diff --git a/include/linux/sunrpc/xprtsock.h b/include/linux/sunrpc/xprtsock.h
index 9bde77061e4f..2c6c2c2783d8 100644
--- a/include/linux/sunrpc/xprtsock.h
+++ b/include/linux/sunrpc/xprtsock.h
@@ -19,6 +19,17 @@ 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 e86958c61a20..6cdf53c489b7 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -241,7 +241,7 @@ struct rpc_clnt *rpc_create(struct rpc_create_args *args)
         struct rpc_xprt *xprt;
         struct rpc_clnt *clnt;
         struct xprt_create xprtargs = {
-                .proto = args->protocol,
+                .ident = args->protocol,
                 .srcaddr = args->saddress,
                 .dstaddr = args->address,
                 .addrlen = args->addrsize,
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 473b48ff4523..282a9a2ec90c 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -104,7 +104,7 @@ int xprt_register_transport(struct xprt_class *transport)
         spin_lock(&xprt_list_lock);
         list_for_each_entry(t, &xprt_list, list) {
                 /* don't register the same transport class twice */
-                if (t == transport)
+                if (t->ident == transport->ident)
                         goto out;
         }
 
@@ -987,15 +987,13 @@ struct rpc_xprt *xprt_create_transport(struct xprt_create *args)
 
         spin_lock(&xprt_list_lock);
         list_for_each_entry(t, &xprt_list, list) {
-                if ((t->family == args->dstaddr->sa_family) &&
-                    (t->protocol == args->proto)) {
+                if (t->ident == args->ident) {
                         spin_unlock(&xprt_list_lock);
                         goto found;
                 }
         }
         spin_unlock(&xprt_list_lock);
-        printk(KERN_ERR "RPC: transport (%u/%d) not supported\n",
-                        args->dstaddr->sa_family, args->proto);
+        printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident);
         return ERR_PTR(-EIO);
 
 found:
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 192a06e3b8c5..b81494a97a5e 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1955,8 +1955,7 @@ static struct xprt_class	xs_udp_transport = {
         .list           = LIST_HEAD_INIT(xs_udp_transport.list),
         .name           = "udp",
         .owner          = THIS_MODULE,
-        .family         = AF_INET,
-        .protocol       = IPPROTO_UDP,
+        .ident          = IPPROTO_UDP,
         .setup          = xs_setup_udp,
 };
 
@@ -1964,8 +1963,7 @@ static struct xprt_class	xs_tcp_transport = {
         .list           = LIST_HEAD_INIT(xs_tcp_transport.list),
         .name           = "tcp",
         .owner          = THIS_MODULE,
-        .family         = AF_INET,
-        .protocol       = IPPROTO_TCP,
+        .ident          = IPPROTO_TCP,
         .setup          = xs_setup_tcp,
 };