2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
5 * Authors: Doug Rabson <dfr@rabson.org>
6 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/limits.h>
38 #include <sys/malloc.h>
40 #include <sys/mutex.h>
43 #include <sys/socket.h>
44 #include <sys/socketvar.h>
49 #include <rpc/rpc_com.h>
52 static enum clnt_stat clnt_reconnect_call(CLIENT *, struct rpc_callextra *,
53 rpcproc_t, struct mbuf *, struct mbuf **, struct timeval);
54 static void clnt_reconnect_geterr(CLIENT *, struct rpc_err *);
55 static bool_t clnt_reconnect_freeres(CLIENT *, xdrproc_t, void *);
56 static void clnt_reconnect_abort(CLIENT *);
57 static bool_t clnt_reconnect_control(CLIENT *, u_int, void *);
58 static void clnt_reconnect_close(CLIENT *);
59 static void clnt_reconnect_destroy(CLIENT *);
61 static struct clnt_ops clnt_reconnect_ops = {
62 .cl_call = clnt_reconnect_call,
63 .cl_abort = clnt_reconnect_abort,
64 .cl_geterr = clnt_reconnect_geterr,
65 .cl_freeres = clnt_reconnect_freeres,
66 .cl_close = clnt_reconnect_close,
67 .cl_destroy = clnt_reconnect_destroy,
68 .cl_control = clnt_reconnect_control
71 static int fake_wchan;
74 clnt_reconnect_create(
75 struct netconfig *nconf, /* network type */
76 struct sockaddr *svcaddr, /* servers address */
77 rpcprog_t program, /* program number */
78 rpcvers_t version, /* version number */
79 size_t sendsz, /* buffer recv size */
80 size_t recvsz) /* buffer send size */
82 CLIENT *cl = NULL; /* client handle */
83 struct rc_data *rc = NULL; /* private data */
85 if (svcaddr == NULL) {
86 rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
90 cl = mem_alloc(sizeof (CLIENT));
91 rc = mem_alloc(sizeof (*rc));
92 mtx_init(&rc->rc_lock, "rc->rc_lock", NULL, MTX_DEF);
93 (void) memcpy(&rc->rc_addr, svcaddr, (size_t)svcaddr->sa_len);
95 rc->rc_prog = program;
96 rc->rc_vers = version;
97 rc->rc_sendsz = sendsz;
98 rc->rc_recvsz = recvsz;
99 rc->rc_timeout.tv_sec = -1;
100 rc->rc_timeout.tv_usec = -1;
101 rc->rc_retry.tv_sec = 3;
102 rc->rc_retry.tv_usec = 0;
103 rc->rc_retries = INT_MAX;
104 rc->rc_privport = FALSE;
105 rc->rc_waitchan = "rpcrecv";
107 rc->rc_connecting = FALSE;
108 rc->rc_closed = FALSE;
109 rc->rc_ucred = crdup(curthread->td_ucred);
110 rc->rc_client = NULL;
113 cl->cl_ops = &clnt_reconnect_ops;
114 cl->cl_private = (caddr_t)(void *)rc;
115 cl->cl_auth = authnone_create();
121 static enum clnt_stat
122 clnt_reconnect_connect(CLIENT *cl)
124 struct thread *td = curthread;
125 struct rc_data *rc = (struct rc_data *)cl->cl_private;
130 struct ucred *oldcred;
131 CLIENT *newclient = NULL;
133 mtx_lock(&rc->rc_lock);
134 while (rc->rc_connecting) {
135 error = msleep(rc, &rc->rc_lock,
136 rc->rc_intr ? PCATCH : 0, "rpcrecon", 0);
138 mtx_unlock(&rc->rc_lock);
143 mtx_unlock(&rc->rc_lock);
144 return (RPC_CANTSEND);
147 mtx_unlock(&rc->rc_lock);
148 return (RPC_SUCCESS);
152 * My turn to attempt a connect. The rc_connecting variable
153 * serializes the following code sequence, so it is guaranteed
154 * that rc_client will still be NULL after it is re-locked below,
155 * since that is the only place it is set non-NULL.
157 rc->rc_connecting = TRUE;
158 mtx_unlock(&rc->rc_lock);
160 oldcred = td->td_ucred;
161 td->td_ucred = rc->rc_ucred;
162 so = __rpc_nconf2socket(rc->rc_nconf);
164 stat = rpc_createerr.cf_stat = RPC_TLIERROR;
165 rpc_createerr.cf_error.re_errno = 0;
166 td->td_ucred = oldcred;
171 bindresvport(so, NULL);
173 if (rc->rc_nconf->nc_semantics == NC_TPI_CLTS)
174 newclient = clnt_dg_create(so,
175 (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
176 rc->rc_sendsz, rc->rc_recvsz);
178 newclient = clnt_vc_create(so,
179 (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
180 rc->rc_sendsz, rc->rc_recvsz, rc->rc_intr);
181 td->td_ucred = oldcred;
185 rc->rc_err = rpc_createerr.cf_error;
186 stat = rpc_createerr.cf_stat;
190 CLNT_CONTROL(newclient, CLSET_FD_CLOSE, 0);
191 CLNT_CONTROL(newclient, CLSET_CONNECT, &one);
192 CLNT_CONTROL(newclient, CLSET_TIMEOUT, &rc->rc_timeout);
193 CLNT_CONTROL(newclient, CLSET_RETRY_TIMEOUT, &rc->rc_retry);
194 CLNT_CONTROL(newclient, CLSET_WAITCHAN, rc->rc_waitchan);
195 CLNT_CONTROL(newclient, CLSET_INTERRUPTIBLE, &rc->rc_intr);
196 if (rc->rc_backchannel != NULL)
197 CLNT_CONTROL(newclient, CLSET_BACKCHANNEL, rc->rc_backchannel);
201 mtx_lock(&rc->rc_lock);
202 KASSERT(rc->rc_client == NULL, ("rc_client not null"));
203 if (!rc->rc_closed) {
204 rc->rc_client = newclient;
207 rc->rc_connecting = FALSE;
209 mtx_unlock(&rc->rc_lock);
213 * It has been closed, so discard the new client.
214 * nb: clnt_[dg|vc]_close()/clnt_[dg|vc]_destroy() cannot
215 * be called with the rc_lock mutex held, since they may
216 * msleep() while holding a different mutex.
218 CLNT_CLOSE(newclient);
219 CLNT_RELEASE(newclient);
225 static enum clnt_stat
227 CLIENT *cl, /* client handle */
228 struct rpc_callextra *ext, /* call metadata */
229 rpcproc_t proc, /* procedure number */
230 struct mbuf *args, /* pointer to args */
231 struct mbuf **resultsp, /* pointer to results */
232 struct timeval utimeout)
234 struct rc_data *rc = (struct rc_data *)cl->cl_private;
241 mtx_lock(&rc->rc_lock);
243 mtx_unlock(&rc->rc_lock);
244 return (RPC_CANTSEND);
247 if (!rc->rc_client) {
248 mtx_unlock(&rc->rc_lock);
249 stat = clnt_reconnect_connect(cl);
250 if (stat == RPC_SYSTEMERROR) {
251 error = tsleep(&fake_wchan,
252 rc->rc_intr ? PCATCH : 0, "rpccon", hz);
253 if (error == EINTR || error == ERESTART)
256 if (tries >= rc->rc_retries)
260 if (stat != RPC_SUCCESS)
262 mtx_lock(&rc->rc_lock);
265 if (!rc->rc_client) {
266 mtx_unlock(&rc->rc_lock);
270 CLNT_ACQUIRE(rc->rc_client);
271 client = rc->rc_client;
272 mtx_unlock(&rc->rc_lock);
273 stat = CLNT_CALL_MBUF(client, ext, proc, args,
276 if (stat != RPC_SUCCESS) {
278 CLNT_GETERR(client, &rc->rc_err);
281 if (stat == RPC_TIMEDOUT) {
283 * Check for async send misfeature for NLM
286 if ((rc->rc_timeout.tv_sec == 0
287 && rc->rc_timeout.tv_usec == 0)
288 || (rc->rc_timeout.tv_sec == -1
289 && utimeout.tv_sec == 0
290 && utimeout.tv_usec == 0)) {
291 CLNT_RELEASE(client);
296 if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND
297 || stat == RPC_CANTRECV) {
299 if (tries >= rc->rc_retries) {
300 CLNT_RELEASE(client);
304 if (ext && ext->rc_feedback)
305 ext->rc_feedback(FEEDBACK_RECONNECT, proc,
306 ext->rc_feedback_arg);
308 mtx_lock(&rc->rc_lock);
310 * Make sure that someone else hasn't already
311 * reconnected by checking if rc_client has changed.
312 * If not, we are done with the client and must
313 * do CLNT_RELEASE(client) twice to dispose of it,
314 * because there is both an initial refcnt and one
315 * acquired by CLNT_ACQUIRE() above.
317 if (rc->rc_client == client) {
318 rc->rc_client = NULL;
319 mtx_unlock(&rc->rc_lock);
320 CLNT_RELEASE(client);
322 mtx_unlock(&rc->rc_lock);
324 CLNT_RELEASE(client);
326 CLNT_RELEASE(client);
329 } while (stat != RPC_SUCCESS);
331 KASSERT(stat != RPC_SUCCESS || *resultsp,
332 ("RPC_SUCCESS without reply"));
338 clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp)
340 struct rc_data *rc = (struct rc_data *)cl->cl_private;
346 * Since this function requires that rc_client be valid, it can
347 * only be called when that is guaranteed to be the case.
350 clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr)
352 struct rc_data *rc = (struct rc_data *)cl->cl_private;
354 return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr));
359 clnt_reconnect_abort(CLIENT *h)
364 * CLNT_CONTROL() on the client returned by clnt_reconnect_create() must
365 * always be called before CLNT_CALL_MBUF() by a single thread only.
368 clnt_reconnect_control(CLIENT *cl, u_int request, void *info)
370 struct rc_data *rc = (struct rc_data *)cl->cl_private;
378 rc->rc_timeout = *(struct timeval *)info;
380 CLNT_CONTROL(rc->rc_client, request, info);
384 *(struct timeval *)info = rc->rc_timeout;
387 case CLSET_RETRY_TIMEOUT:
388 rc->rc_retry = *(struct timeval *)info;
390 CLNT_CONTROL(rc->rc_client, request, info);
393 case CLGET_RETRY_TIMEOUT:
394 *(struct timeval *)info = rc->rc_retry;
398 *(uint32_t *)info = rc->rc_vers;
402 rc->rc_vers = *(uint32_t *) info;
404 CLNT_CONTROL(rc->rc_client, CLSET_VERS, info);
408 *(uint32_t *)info = rc->rc_prog;
412 rc->rc_prog = *(uint32_t *) info;
414 CLNT_CONTROL(rc->rc_client, request, info);
418 rc->rc_waitchan = (char *)info;
420 CLNT_CONTROL(rc->rc_client, request, info);
424 *(const char **) info = rc->rc_waitchan;
427 case CLSET_INTERRUPTIBLE:
428 rc->rc_intr = *(int *) info;
430 CLNT_CONTROL(rc->rc_client, request, info);
433 case CLGET_INTERRUPTIBLE:
434 *(int *) info = rc->rc_intr;
438 rc->rc_retries = *(int *) info;
442 *(int *) info = rc->rc_retries;
446 rc->rc_privport = *(int *) info;
450 *(int *) info = rc->rc_privport;
453 case CLSET_BACKCHANNEL:
454 xprt = (SVCXPRT *)info;
456 rc->rc_backchannel = info;
467 clnt_reconnect_close(CLIENT *cl)
469 struct rc_data *rc = (struct rc_data *)cl->cl_private;
472 mtx_lock(&rc->rc_lock);
475 mtx_unlock(&rc->rc_lock);
479 rc->rc_closed = TRUE;
480 client = rc->rc_client;
481 rc->rc_client = NULL;
483 mtx_unlock(&rc->rc_lock);
487 CLNT_RELEASE(client);
492 clnt_reconnect_destroy(CLIENT *cl)
494 struct rc_data *rc = (struct rc_data *)cl->cl_private;
498 CLNT_DESTROY(rc->rc_client);
499 if (rc->rc_backchannel) {
500 xprt = (SVCXPRT *)rc->rc_backchannel;
501 xprt_unregister(xprt);
504 crfree(rc->rc_ucred);
505 mtx_destroy(&rc->rc_lock);
506 mem_free(rc, sizeof(*rc));
507 mem_free(cl, sizeof (CLIENT));