xref: /freebsd/sys/rpc/clnt_rc.c (revision ea906c4152774dff300bb26fbfc1e4188351c89a)
1 /*-
2  * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
3  * Authors: Doug Rabson <dfr@rabson.org>
4  * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/limits.h>
34 #include <sys/lock.h>
35 #include <sys/malloc.h>
36 #include <sys/mbuf.h>
37 #include <sys/mutex.h>
38 #include <sys/pcpu.h>
39 #include <sys/proc.h>
40 #include <sys/socket.h>
41 #include <sys/socketvar.h>
42 #include <sys/time.h>
43 #include <sys/uio.h>
44 
45 #include <rpc/rpc.h>
46 #include <rpc/rpc_com.h>
47 
48 static enum clnt_stat clnt_reconnect_call(CLIENT *, struct rpc_callextra *,
49     rpcproc_t, xdrproc_t, void *, xdrproc_t, void *, struct timeval);
50 static void clnt_reconnect_geterr(CLIENT *, struct rpc_err *);
51 static bool_t clnt_reconnect_freeres(CLIENT *, xdrproc_t, void *);
52 static void clnt_reconnect_abort(CLIENT *);
53 static bool_t clnt_reconnect_control(CLIENT *, u_int, void *);
54 static void clnt_reconnect_destroy(CLIENT *);
55 
56 static 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 
65 struct 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 
82 CLIENT *
83 clnt_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 
127 static enum clnt_stat
128 clnt_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);
137 again:
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 
189 out:
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 
198 static enum clnt_stat
199 clnt_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 
272 static void
273 clnt_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 
283 static bool_t
284 clnt_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*/
292 static void
293 clnt_reconnect_abort(CLIENT *h)
294 {
295 }
296 
297 static bool_t
298 clnt_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 
381 static void
382 clnt_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