Commit 7f554890 authored by Trond Myklebust's avatar Trond Myklebust
Browse files

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: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
parent d9ddbf5d

include/linux/sunrpc/clnt.h

+11 −0
Original line number Diff line number Diff line
@@ -186,6 +186,17 @@ int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt, 
			int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),

			void *data);



int 		rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,

			struct rpc_xprt_switch *xps,

			struct rpc_xprt *xprt,

			void *dummy);

int		rpc_clnt_add_xprt(struct rpc_clnt *, struct xprt_create *,

			int (*setup)(struct rpc_clnt *,

				struct rpc_xprt_switch *,

				struct rpc_xprt *,

				void *),

			void *data);



const char *rpc_proc_name(const struct rpc_task *task);

#endif /* __KERNEL__ */

#endif /* _LINUX_SUNRPC_CLNT_H */

net/sunrpc/clnt.c

+131 −2
Original line number Diff line number Diff line
@@ -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)

{