diff options
| -rw-r--r-- | include/linux/sunrpc/xprt.h | 11 | ||||
| -rw-r--r-- | net/sunrpc/xprt.c | 75 |
2 files changed, 86 insertions, 0 deletions
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 513b0657e14..7b6b137eca9 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -208,6 +208,15 @@ struct rpc_xprtsock_create { struct rpc_timeout * timeout; /* optional timeout parameters */ }; +struct xprt_class { + struct list_head list; + unsigned short family; + int protocol; + struct rpc_xprt * (*setup)(struct rpc_xprtsock_create *); + struct module *owner; + char name[32]; +}; + /* * Transport operations used by ULPs */ @@ -239,6 +248,8 @@ static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 * /* * Transport switch helper functions */ +int xprt_register_transport(struct xprt_class *type); +int xprt_unregister_transport(struct xprt_class *type); void xprt_set_retrans_timeout_def(struct rpc_task *task); void xprt_set_retrans_timeout_rtt(struct rpc_task *task); void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index bc13616e7fd..520859622af 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -62,6 +62,9 @@ static inline void do_xprt_reserve(struct rpc_task *); static void xprt_connect_status(struct rpc_task *task); static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); +static spinlock_t xprt_list_lock = SPIN_LOCK_UNLOCKED; +static LIST_HEAD(xprt_list); + /* * The transport code maintains an estimate on the maximum number of out- * standing RPC requests, using a smoothed version of the congestion @@ -81,6 +84,78 @@ static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) /** + * xprt_register_transport - register a transport implementation + * @transport: transport to register + * + * If a transport implementation is loaded as a kernel module, it can + * call this interface to make itself known to the RPC client. + * + * Returns: + * 0: transport successfully registered + * -EEXIST: transport already registered + * -EINVAL: transport module being unloaded + */ +int xprt_register_transport(struct xprt_class *transport) +{ + struct xprt_class *t; + int result; + + result = -EEXIST; + spin_lock(&xprt_list_lock); + list_for_each_entry(t, &xprt_list, list) { + /* don't register the same transport class twice */ + if (t == transport) + goto out; + } + + result = -EINVAL; + if (try_module_get(THIS_MODULE)) { + list_add_tail(&transport->list, &xprt_list); + printk(KERN_INFO "RPC: Registered %s transport module.\n", + transport->name); + result = 0; + } + +out: + spin_unlock(&xprt_list_lock); + return result; +} +EXPORT_SYMBOL_GPL(xprt_register_transport); + +/** + * xprt_unregister_transport - unregister a transport implementation + * transport: transport to unregister + * + * Returns: + * 0: transport successfully unregistered + * -ENOENT: transport never registered + */ +int xprt_unregister_transport(struct xprt_class *transport) +{ + struct xprt_class *t; + int result; + + result = 0; + spin_lock(&xprt_list_lock); + list_for_each_entry(t, &xprt_list, list) { + if (t == transport) { + printk(KERN_INFO + "RPC: Unregistered %s transport module.\n", + transport->name); + list_del_init(&transport->list); + module_put(THIS_MODULE); + goto out; + } + } + result = -ENOENT; + +out: + spin_unlock(&xprt_list_lock); + return result; +} +EXPORT_SYMBOL_GPL(xprt_unregister_transport); + +/** * xprt_reserve_xprt - serialize write access to transports * @task: task that is requesting access to the transport * |