clnt_rc.c revision 181684 
1226586Sdim/*-
2226586Sdim * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
3226586Sdim * Authors: Doug Rabson <dfr@rabson.org>
4226586Sdim * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
5226586Sdim *
6226586Sdim * Redistribution and use in source and binary forms, with or without
7226586Sdim * modification, are permitted provided that the following conditions
8226586Sdim * are met:
9226586Sdim * 1. Redistributions of source code must retain the above copyright
10226586Sdim *    notice, this list of conditions and the following disclaimer.
11226586Sdim * 2. Redistributions in binary form must reproduce the above copyright
12226586Sdim *    notice, this list of conditions and the following disclaimer in the
13226586Sdim *    documentation and/or other materials provided with the distribution.
14249423Sdim *
15226586Sdim * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16226586Sdim * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17226586Sdim * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18226586Sdim * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19226586Sdim * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20226586Sdim * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21226586Sdim * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22226586Sdim * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23226586Sdim * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24226586Sdim * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25226586Sdim * SUCH DAMAGE.
26226586Sdim */
27226586Sdim
28226586Sdim#include <sys/cdefs.h>
29226586Sdim__FBSDID("$FreeBSD: head/sys/rpc/clnt_rc.c 181684 2008-08-13 12:04:54Z dfr $");
30226586Sdim
31226586Sdim#include <sys/param.h>
32226586Sdim#include <sys/systm.h>
33226586Sdim#include <sys/limits.h>
34226586Sdim#include <sys/lock.h>
35226586Sdim#include <sys/malloc.h>
36226586Sdim#include <sys/mbuf.h>
37226586Sdim#include <sys/mutex.h>
38226586Sdim#include <sys/pcpu.h>
39226586Sdim#include <sys/proc.h>
40226586Sdim#include <sys/socket.h>
41226586Sdim#include <sys/socketvar.h>
42226586Sdim#include <sys/time.h>
43226586Sdim#include <sys/uio.h>
44226586Sdim
45#include <rpc/rpc.h>
46#include <rpc/rpc_com.h>
47
48static enum clnt_stat clnt_reconnect_call(CLIENT *, struct rpc_callextra *,
49    rpcproc_t, xdrproc_t, void *, xdrproc_t, void *, struct timeval);
50static void clnt_reconnect_geterr(CLIENT *, struct rpc_err *);
51static bool_t clnt_reconnect_freeres(CLIENT *, xdrproc_t, void *);
52static void clnt_reconnect_abort(CLIENT *);
53static bool_t clnt_reconnect_control(CLIENT *, u_int, void *);
54static void clnt_reconnect_destroy(CLIENT *);
55
56static struct clnt_ops clnt_reconnect_ops = {
57	.cl_call =	clnt_reconnect_call,
58	.cl_abort =	clnt_reconnect_abort,
59	.cl_geterr =	clnt_reconnect_geterr,
60	.cl_freeres =	clnt_reconnect_freeres,
61	.cl_destroy =	clnt_reconnect_destroy,
62	.cl_control =	clnt_reconnect_control
63};
64
65struct rc_data {
66	struct mtx		rc_lock;
67	struct sockaddr_storage	rc_addr; /* server address */
68	struct netconfig*	rc_nconf; /* network type */
69	rpcprog_t		rc_prog;  /* program number */
70	rpcvers_t		rc_vers;  /* version number */
71	size_t			rc_sendsz;
72	size_t			rc_recvsz;
73	struct timeval		rc_timeout;
74	struct timeval		rc_retry;
75	int			rc_retries;
76	const char		*rc_waitchan;
77	int			rc_intr;
78	int			rc_connecting;
79	CLIENT*			rc_client; /* underlying RPC client */
80};
81
82CLIENT *
83clnt_reconnect_create(
84	struct netconfig *nconf,	/* network type */
85	struct sockaddr *svcaddr,	/* servers address */
86	rpcprog_t program,		/* program number */
87	rpcvers_t version,		/* version number */
88	size_t sendsz,			/* buffer recv size */
89	size_t recvsz)			/* buffer send size */
90{
91	CLIENT *cl = NULL;		/* client handle */
92	struct rc_data *rc = NULL;	/* private data */
93
94	if (svcaddr == NULL) {
95		rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
96		return (NULL);
97	}
98
99	cl = mem_alloc(sizeof (CLIENT));
100	rc = mem_alloc(sizeof (*rc));
101	mtx_init(&rc->rc_lock, "rc->rc_lock", NULL, MTX_DEF);
102	(void) memcpy(&rc->rc_addr, svcaddr, (size_t)svcaddr->sa_len);
103	rc->rc_nconf = nconf;
104	rc->rc_prog = program;
105	rc->rc_vers = version;
106	rc->rc_sendsz = sendsz;
107	rc->rc_recvsz = recvsz;
108	rc->rc_timeout.tv_sec = -1;
109	rc->rc_timeout.tv_usec = -1;
110	rc->rc_retry.tv_sec = 3;
111	rc->rc_retry.tv_usec = 0;
112	rc->rc_retries = INT_MAX;
113	rc->rc_waitchan = "rpcrecv";
114	rc->rc_intr = 0;
115	rc->rc_connecting = FALSE;
116	rc->rc_client = NULL;
117
118	cl->cl_refs = 1;
119	cl->cl_ops = &clnt_reconnect_ops;
120	cl->cl_private = (caddr_t)(void *)rc;
121	cl->cl_auth = authnone_create();
122	cl->cl_tp = NULL;
123	cl->cl_netid = NULL;
124	return (cl);
125}
126
127static enum clnt_stat
128clnt_reconnect_connect(CLIENT *cl)
129{
130	struct rc_data *rc = (struct rc_data *)cl->cl_private;
131	struct socket *so;
132	enum clnt_stat stat;
133	int error;
134	int one = 1;
135
136	mtx_lock(&rc->rc_lock);
137again:
138	if (rc->rc_connecting) {
139		while (!rc->rc_client) {
140			error = msleep(rc, &rc->rc_lock,
141			    rc->rc_intr ? PCATCH : 0, "rpcrecon", 0);
142			if (error) {
143				mtx_unlock(&rc->rc_lock);
144				return (RPC_INTR);
145			}
146		}
147		/*
148		 * If the other guy failed to connect, we might as
149		 * well have another go.
150		 */
151		if (!rc->rc_client && !rc->rc_connecting)
152			goto again;
153		mtx_unlock(&rc->rc_lock);
154		return (RPC_SUCCESS);
155	} else {
156		rc->rc_connecting = TRUE;
157	}
158	mtx_unlock(&rc->rc_lock);
159
160	so = __rpc_nconf2socket(rc->rc_nconf);
161	if (!so) {
162		stat = rpc_createerr.cf_stat = RPC_TLIERROR;
163		rpc_createerr.cf_error.re_errno = 0;
164		goto out;
165	}
166
167	if (rc->rc_nconf->nc_semantics == NC_TPI_CLTS)
168		rc->rc_client = clnt_dg_create(so,
169		    (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
170		    rc->rc_sendsz, rc->rc_recvsz);
171	else
172		rc->rc_client = clnt_vc_create(so,
173		    (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
174		    rc->rc_sendsz, rc->rc_recvsz);
175
176	if (!rc->rc_client) {
177		stat = rpc_createerr.cf_stat;
178		goto out;
179	}
180
181	CLNT_CONTROL(rc->rc_client, CLSET_FD_CLOSE, 0);
182	CLNT_CONTROL(rc->rc_client, CLSET_CONNECT, &one);
183	CLNT_CONTROL(rc->rc_client, CLSET_TIMEOUT, &rc->rc_timeout);
184	CLNT_CONTROL(rc->rc_client, CLSET_RETRY_TIMEOUT, &rc->rc_retry);
185	CLNT_CONTROL(rc->rc_client, CLSET_WAITCHAN, &rc->rc_waitchan);
186	CLNT_CONTROL(rc->rc_client, CLSET_INTERRUPTIBLE, &rc->rc_intr);
187	stat = RPC_SUCCESS;
188
189out:
190	mtx_lock(&rc->rc_lock);
191	rc->rc_connecting = FALSE;
192	wakeup(rc);
193	mtx_unlock(&rc->rc_lock);
194
195	return (stat);
196}
197
198static enum clnt_stat
199clnt_reconnect_call(
200	CLIENT		*cl,		/* client handle */
201	struct rpc_callextra *ext,	/* call metadata */
202	rpcproc_t	proc,		/* procedure number */
203	xdrproc_t	xargs,		/* xdr routine for args */
204	void		*argsp,		/* pointer to args */
205	xdrproc_t	xresults,	/* xdr routine for results */
206	void		*resultsp,	/* pointer to results */
207	struct timeval	utimeout)	/* seconds to wait before giving up */
208{
209	struct rc_data *rc = (struct rc_data *)cl->cl_private;
210	CLIENT *client;
211	enum clnt_stat stat;
212	int tries;
213
214	tries = 0;
215	do {
216		if (!rc->rc_client) {
217			stat = clnt_reconnect_connect(cl);
218			if (stat != RPC_SUCCESS)
219				return (stat);
220		}
221
222		mtx_lock(&rc->rc_lock);
223		CLNT_ACQUIRE(rc->rc_client);
224		client = rc->rc_client;
225		mtx_unlock(&rc->rc_lock);
226		stat = CLNT_CALL_EXT(client, ext, proc, xargs, argsp,
227		    xresults, resultsp, utimeout);
228
229		CLNT_RELEASE(client);
230		if (stat == RPC_TIMEDOUT) {
231			/*
232			 * Check for async send misfeature for NLM
233			 * protocol.
234			 */
235			if ((rc->rc_timeout.tv_sec == 0
236				&& rc->rc_timeout.tv_usec == 0)
237			    || (rc->rc_timeout.tv_sec == -1
238				&& utimeout.tv_sec == 0
239				&& utimeout.tv_usec == 0)) {
240				break;
241			}
242		}
243
244		if (stat == RPC_INTR)
245			break;
246
247		if (stat != RPC_SUCCESS) {
248			tries++;
249			if (tries >= rc->rc_retries)
250				break;
251
252			if (ext && ext->rc_feedback)
253				ext->rc_feedback(FEEDBACK_RECONNECT, proc,
254				    ext->rc_feedback_arg);
255
256			mtx_lock(&rc->rc_lock);
257			/*
258			 * Make sure that someone else hasn't already
259			 * reconnected.
260			 */
261			if (rc->rc_client == client) {
262				CLNT_RELEASE(rc->rc_client);
263				rc->rc_client = NULL;
264			}
265			mtx_unlock(&rc->rc_lock);
266		}
267	} while (stat != RPC_SUCCESS);
268
269	return (stat);
270}
271
272static void
273clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp)
274{
275	struct rc_data *rc = (struct rc_data *)cl->cl_private;
276
277	if (rc->rc_client)
278		CLNT_GETERR(rc->rc_client, errp);
279	else
280		memset(errp, 0, sizeof(*errp));
281}
282
283static bool_t
284clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr)
285{
286	struct rc_data *rc = (struct rc_data *)cl->cl_private;
287
288	return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr));
289}
290
291/*ARGSUSED*/
292static void
293clnt_reconnect_abort(CLIENT *h)
294{
295}
296
297static bool_t
298clnt_reconnect_control(CLIENT *cl, u_int request, void *info)
299{
300	struct rc_data *rc = (struct rc_data *)cl->cl_private;
301
302	if (info == NULL) {
303		return (FALSE);
304	}
305	switch (request) {
306	case CLSET_TIMEOUT:
307		rc->rc_timeout = *(struct timeval *)info;
308		if (rc->rc_client)
309			CLNT_CONTROL(rc->rc_client, request, info);
310		break;
311
312	case CLGET_TIMEOUT:
313		*(struct timeval *)info = rc->rc_timeout;
314		break;
315
316	case CLSET_RETRY_TIMEOUT:
317		rc->rc_retry = *(struct timeval *)info;
318		if (rc->rc_client)
319			CLNT_CONTROL(rc->rc_client, request, info);
320		break;
321
322	case CLGET_RETRY_TIMEOUT:
323		*(struct timeval *)info = rc->rc_retry;
324		break;
325
326	case CLGET_VERS:
327		*(uint32_t *)info = rc->rc_vers;
328		break;
329
330	case CLSET_VERS:
331		rc->rc_vers = *(uint32_t *) info;
332		if (rc->rc_client)
333			CLNT_CONTROL(rc->rc_client, CLSET_VERS, info);
334		break;
335
336	case CLGET_PROG:
337		*(uint32_t *)info = rc->rc_prog;
338		break;
339
340	case CLSET_PROG:
341		rc->rc_prog = *(uint32_t *) info;
342		if (rc->rc_client)
343			CLNT_CONTROL(rc->rc_client, request, info);
344		break;
345
346	case CLSET_WAITCHAN:
347		rc->rc_waitchan = *(const char **)info;
348		if (rc->rc_client)
349			CLNT_CONTROL(rc->rc_client, request, info);
350		break;
351
352	case CLGET_WAITCHAN:
353		*(const char **) info = rc->rc_waitchan;
354		break;
355
356	case CLSET_INTERRUPTIBLE:
357		rc->rc_intr = *(int *) info;
358		if (rc->rc_client)
359			CLNT_CONTROL(rc->rc_client, request, info);
360		break;
361
362	case CLGET_INTERRUPTIBLE:
363		*(int *) info = rc->rc_intr;
364		break;
365
366	case CLSET_RETRIES:
367		rc->rc_retries = *(int *) info;
368		break;
369
370	case CLGET_RETRIES:
371		*(int *) info = rc->rc_retries;
372		break;
373
374	default:
375		return (FALSE);
376	}
377
378	return (TRUE);
379}
380
381static void
382clnt_reconnect_destroy(CLIENT *cl)
383{
384	struct rc_data *rc = (struct rc_data *)cl->cl_private;
385
386	if (rc->rc_client)
387		CLNT_DESTROY(rc->rc_client);
388	mtx_destroy(&rc->rc_lock);
389	mem_free(rc, sizeof(*rc));
390	mem_free(cl, sizeof (CLIENT));
391}
392