SUNRPC: Finish API to load RPC transport implementations dynamically
Allow RPC client transport implementations to be loaded as needed, or
as they become available from distributors or third-party vendors.
Note that we leave the IP sockets implementation in sunrpc.o
permanently, as IP functionality is always available in any
kernel that runs NFS.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 5208596..7f8c60b 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -983,19 +983,23 @@
{
struct rpc_xprt *xprt;
struct rpc_rqst *req;
+ struct xprt_class *t;
- switch (args->proto) {
- case IPPROTO_UDP:
- xprt = xs_setup_udp(args);
- break;
- case IPPROTO_TCP:
- xprt = xs_setup_tcp(args);
- break;
- default:
- printk(KERN_ERR "RPC: unrecognized transport protocol: %d\n",
- args->proto);
- return ERR_PTR(-EIO);
+ spin_lock(&xprt_list_lock);
+ list_for_each_entry(t, &xprt_list, list) {
+ if ((t->family == args->dstaddr->sa_family) &&
+ (t->protocol == args->proto)) {
+ 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);
+ return ERR_PTR(-EIO);
+
+found:
+ xprt = t->setup(args);
if (IS_ERR(xprt)) {
dprintk("RPC: xprt_create_transport: failed, %ld\n",
-PTR_ERR(xprt));
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 5bdce8f..3bc9c92 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -20,6 +20,7 @@
#include <linux/types.h>
#include <linux/slab.h>
+#include <linux/module.h>
#include <linux/capability.h>
#include <linux/pagemap.h>
#include <linux/errno.h>
@@ -777,6 +778,7 @@
xs_free_peer_addresses(xprt);
kfree(xprt->slot);
kfree(xprt);
+ module_put(THIS_MODULE);
}
static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
@@ -1782,7 +1784,8 @@
.print_stats = xs_tcp_print_stats,
};
-static struct rpc_xprt *xs_setup_xprt(struct rpc_xprtsock_create *args, unsigned int slot_table_size)
+static struct rpc_xprt *xs_setup_xprt(struct rpc_xprtsock_create *args,
+ unsigned int slot_table_size)
{
struct rpc_xprt *xprt;
struct sock_xprt *new;
@@ -1876,7 +1879,12 @@
dprintk("RPC: set up transport to address %s\n",
xprt->address_strings[RPC_DISPLAY_ALL]);
- return xprt;
+ if (try_module_get(THIS_MODULE))
+ return xprt;
+
+ kfree(xprt->slot);
+ kfree(xprt);
+ return ERR_PTR(-EINVAL);
}
/**
@@ -1934,11 +1942,34 @@
dprintk("RPC: set up transport to address %s\n",
xprt->address_strings[RPC_DISPLAY_ALL]);
- return 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,
+ .family = AF_INET,
+ .protocol = IPPROTO_UDP,
+ .setup = xs_setup_udp,
+};
+
+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,
+ .setup = xs_setup_tcp,
+};
+
/**
- * init_socket_xprt - set up xprtsock's sysctls
+ * init_socket_xprt - set up xprtsock's sysctls, register with RPC client
*
*/
int init_socket_xprt(void)
@@ -1948,11 +1979,14 @@
sunrpc_table_header = register_sysctl_table(sunrpc_table);
#endif
+ xprt_register_transport(&xs_udp_transport);
+ xprt_register_transport(&xs_tcp_transport);
+
return 0;
}
/**
- * cleanup_socket_xprt - remove xprtsock's sysctls
+ * cleanup_socket_xprt - remove xprtsock's sysctls, unregister
*
*/
void cleanup_socket_xprt(void)
@@ -1963,4 +1997,7 @@
sunrpc_table_header = NULL;
}
#endif
+
+ xprt_unregister_transport(&xs_udp_transport);
+ xprt_unregister_transport(&xs_tcp_transport);
}