From 7f554890587c63ca4c087d6bcc4a9fe368e57484 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sat, 30 Jan 2016 23:43:35 -0500 Subject: SUNRPC: Allow addition of new transports to a struct rpc_clnt Add a function to allow creation and addition of a new transport to an existing rpc_clnt Signed-off-by: Trond Myklebust --- net/sunrpc/clnt.c | 133 +++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 131 insertions(+), 2 deletions(-) (limited to 'net/sunrpc/clnt.c') diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 4b6ceb7c5e1d..7e0c9bf22df8 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -2492,7 +2492,10 @@ static int rpc_ping(struct rpc_clnt *clnt) return err; } -struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) +static +struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, + struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, + const struct rpc_call_ops *ops, void *data) { struct rpc_message msg = { .rpc_proc = &rpcproc_null, @@ -2500,14 +2503,140 @@ struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int }; struct rpc_task_setup task_setup_data = { .rpc_client = clnt, + .rpc_xprt = xprt, .rpc_message = &msg, - .callback_ops = &rpc_default_ops, + .callback_ops = (ops != NULL) ? ops : &rpc_default_ops, + .callback_data = data, .flags = flags, }; + return rpc_run_task(&task_setup_data); } + +struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) +{ + return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); +} EXPORT_SYMBOL_GPL(rpc_call_null); +struct rpc_cb_add_xprt_calldata { + struct rpc_xprt_switch *xps; + struct rpc_xprt *xprt; +}; + +static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) +{ + struct rpc_cb_add_xprt_calldata *data = calldata; + + if (task->tk_status == 0) + rpc_xprt_switch_add_xprt(data->xps, data->xprt); +} + +static void rpc_cb_add_xprt_release(void *calldata) +{ + struct rpc_cb_add_xprt_calldata *data = calldata; + + xprt_put(data->xprt); + xprt_switch_put(data->xps); + kfree(data); +} + +const static struct rpc_call_ops rpc_cb_add_xprt_call_ops = { + .rpc_call_done = rpc_cb_add_xprt_done, + .rpc_release = rpc_cb_add_xprt_release, +}; + +/** + * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt + * @clnt: pointer to struct rpc_clnt + * @xps: pointer to struct rpc_xprt_switch, + * @xprt: pointer struct rpc_xprt + * @dummy: unused + */ +int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, + struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, + void *dummy) +{ + struct rpc_cb_add_xprt_calldata *data; + struct rpc_cred *cred; + struct rpc_task *task; + + data = kmalloc(sizeof(*data), GFP_NOFS); + if (!data) + return -ENOMEM; + data->xps = xprt_switch_get(xps); + data->xprt = xprt_get(xprt); + + cred = authnull_ops.lookup_cred(NULL, NULL, 0); + task = rpc_call_null_helper(clnt, xprt, cred, + RPC_TASK_SOFT|RPC_TASK_SOFTCONN|RPC_TASK_ASYNC, + &rpc_cb_add_xprt_call_ops, data); + put_rpccred(cred); + if (IS_ERR(task)) + return PTR_ERR(task); + rpc_put_task(task); + return 1; +} +EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); + +/** + * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt + * @clnt: pointer to struct rpc_clnt + * @xprtargs: pointer to struct xprt_create + * @setup: callback to test and/or set up the connection + * @data: pointer to setup function data + * + * Creates a new transport using the parameters set in args and + * adds it to clnt. + * If ping is set, then test that connectivity succeeds before + * adding the new transport. + * + */ +int rpc_clnt_add_xprt(struct rpc_clnt *clnt, + struct xprt_create *xprtargs, + int (*setup)(struct rpc_clnt *, + struct rpc_xprt_switch *, + struct rpc_xprt *, + void *), + void *data) +{ + struct rpc_xprt_switch *xps; + struct rpc_xprt *xprt; + unsigned char resvport; + int ret = 0; + + rcu_read_lock(); + xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); + xprt = xprt_iter_xprt(&clnt->cl_xpi); + if (xps == NULL || xprt == NULL) { + rcu_read_unlock(); + return -EAGAIN; + } + resvport = xprt->resvport; + rcu_read_unlock(); + + xprt = xprt_create_transport(xprtargs); + if (IS_ERR(xprt)) { + ret = PTR_ERR(xprt); + goto out_put_switch; + } + xprt->resvport = resvport; + + rpc_xprt_switch_set_roundrobin(xps); + if (setup) { + ret = setup(clnt, xps, xprt, data); + if (ret != 0) + goto out_put_xprt; + } + rpc_xprt_switch_add_xprt(xps, xprt); +out_put_xprt: + xprt_put(xprt); +out_put_switch: + xprt_switch_put(xps); + return ret; +} +EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); + #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) static void rpc_show_header(void) { -- cgit v1.2.3-59-g8ed1b