xref: /freebsd/sbin/hastd/control.c (revision 10b9d77bf1ccf2f3affafa6261692cb92cf7e992)
1 /*-
2  * Copyright (c) 2009-2010 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Pawel Jakub Dawidek under sponsorship from
6  * the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
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.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/types.h>
34 #include <sys/wait.h>
35 
36 #include <assert.h>
37 #include <errno.h>
38 #include <pthread.h>
39 #include <signal.h>
40 #include <stdio.h>
41 #include <string.h>
42 #include <unistd.h>
43 
44 #include "hast.h"
45 #include "hastd.h"
46 #include "hast_proto.h"
47 #include "hooks.h"
48 #include "nv.h"
49 #include "pjdlog.h"
50 #include "proto.h"
51 #include "subr.h"
52 
53 #include "control.h"
54 
55 void
56 child_cleanup(struct hast_resource *res)
57 {
58 
59 	proto_close(res->hr_ctrl);
60 	res->hr_ctrl = NULL;
61 	if (res->hr_event != NULL) {
62 		proto_close(res->hr_event);
63 		res->hr_event = NULL;
64 	}
65 	if (res->hr_conn != NULL) {
66 		proto_close(res->hr_conn);
67 		res->hr_conn = NULL;
68 	}
69 	res->hr_workerpid = 0;
70 }
71 
72 static void
73 control_set_role_common(struct hastd_config *cfg, struct nv *nvout,
74     uint8_t role, struct hast_resource *res, const char *name, unsigned int no)
75 {
76 	int oldrole;
77 
78 	/* Name is always needed. */
79 	if (name != NULL)
80 		nv_add_string(nvout, name, "resource%u", no);
81 
82 	if (res == NULL) {
83 		assert(cfg != NULL);
84 		assert(name != NULL);
85 
86 		TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
87 			if (strcmp(res->hr_name, name) == 0)
88 				break;
89 		}
90 		if (res == NULL) {
91 			nv_add_int16(nvout, EHAST_NOENTRY, "error%u", no);
92 			return;
93 		}
94 	}
95 	assert(res != NULL);
96 
97 	/* Send previous role back. */
98 	nv_add_string(nvout, role2str(res->hr_role), "role%u", no);
99 
100 	/* Nothing changed, return here. */
101 	if (role == res->hr_role)
102 		return;
103 
104 	pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
105 	pjdlog_info("Role changed to %s.", role2str(role));
106 
107 	/* Change role to the new one. */
108 	oldrole = res->hr_role;
109 	res->hr_role = role;
110 	pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
111 
112 	/*
113 	 * If previous role was primary or secondary we have to kill process
114 	 * doing that work.
115 	 */
116 	if (res->hr_workerpid != 0) {
117 		if (kill(res->hr_workerpid, SIGTERM) < 0) {
118 			pjdlog_errno(LOG_WARNING,
119 			    "Unable to kill worker process %u",
120 			    (unsigned int)res->hr_workerpid);
121 		} else if (waitpid(res->hr_workerpid, NULL, 0) !=
122 		    res->hr_workerpid) {
123 			pjdlog_errno(LOG_WARNING,
124 			    "Error while waiting for worker process %u",
125 			    (unsigned int)res->hr_workerpid);
126 		} else {
127 			pjdlog_debug(1, "Worker process %u stopped.",
128 			    (unsigned int)res->hr_workerpid);
129 		}
130 		child_cleanup(res);
131 	}
132 
133 	/* Start worker process if we are changing to primary. */
134 	if (role == HAST_ROLE_PRIMARY)
135 		hastd_primary(res);
136 	pjdlog_prefix_set("%s", "");
137 	hook_exec(res->hr_exec, "role", res->hr_name, role2str(oldrole),
138 	    role2str(res->hr_role), NULL);
139 }
140 
141 void
142 control_set_role(struct hast_resource *res, uint8_t role)
143 {
144 
145 	control_set_role_common(NULL, NULL, role, res, NULL, 0);
146 }
147 
148 static void
149 control_status_worker(struct hast_resource *res, struct nv *nvout,
150     unsigned int no)
151 {
152 	struct nv *cnvin, *cnvout;
153 	const char *str;
154 	int error;
155 
156 	cnvin = cnvout = NULL;
157 	error = 0;
158 
159 	/*
160 	 * Prepare and send command to worker process.
161 	 */
162 	cnvout = nv_alloc();
163 	nv_add_uint8(cnvout, HASTCTL_STATUS, "cmd");
164 	error = nv_error(cnvout);
165 	if (error != 0) {
166 		pjdlog_common(LOG_ERR, 0, error,
167 		    "Unable to prepare control header");
168 		goto end;
169 	}
170 	if (hast_proto_send(res, res->hr_ctrl, cnvout, NULL, 0) < 0) {
171 		error = errno;
172 		pjdlog_errno(LOG_ERR, "Unable to send control header");
173 		goto end;
174 	}
175 
176 	/*
177 	 * Receive response.
178 	 */
179 	if (hast_proto_recv_hdr(res->hr_ctrl, &cnvin) < 0) {
180 		error = errno;
181 		pjdlog_errno(LOG_ERR, "Unable to receive control header");
182 		goto end;
183 	}
184 
185 	error = nv_get_int16(cnvin, "error");
186 	if (error != 0)
187 		goto end;
188 
189 	if ((str = nv_get_string(cnvin, "status")) == NULL) {
190 		error = ENOENT;
191 		pjdlog_errno(LOG_ERR, "Field 'status' is missing.");
192 		goto end;
193 	}
194 	nv_add_string(nvout, str, "status%u", no);
195 	nv_add_uint64(nvout, nv_get_uint64(cnvin, "dirty"), "dirty%u", no);
196 	nv_add_uint32(nvout, nv_get_uint32(cnvin, "extentsize"),
197 	    "extentsize%u", no);
198 	nv_add_uint32(nvout, nv_get_uint32(cnvin, "keepdirty"),
199 	    "keepdirty%u", no);
200 end:
201 	if (cnvin != NULL)
202 		nv_free(cnvin);
203 	if (cnvout != NULL)
204 		nv_free(cnvout);
205 	if (error != 0)
206 		nv_add_int16(nvout, error, "error");
207 }
208 
209 static void
210 control_status(struct hastd_config *cfg, struct nv *nvout,
211     struct hast_resource *res, const char *name, unsigned int no)
212 {
213 
214 	assert(cfg != NULL);
215 	assert(nvout != NULL);
216 	assert(name != NULL);
217 
218 	/* Name is always needed. */
219 	nv_add_string(nvout, name, "resource%u", no);
220 
221 	if (res == NULL) {
222 		TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
223 			if (strcmp(res->hr_name, name) == 0)
224 				break;
225 		}
226 		if (res == NULL) {
227 			nv_add_int16(nvout, EHAST_NOENTRY, "error%u", no);
228 			return;
229 		}
230 	}
231 	assert(res != NULL);
232 	nv_add_string(nvout, res->hr_provname, "provname%u", no);
233 	nv_add_string(nvout, res->hr_localpath, "localpath%u", no);
234 	nv_add_string(nvout, res->hr_remoteaddr, "remoteaddr%u", no);
235 	switch (res->hr_replication) {
236 	case HAST_REPLICATION_FULLSYNC:
237 		nv_add_string(nvout, "fullsync", "replication%u", no);
238 		break;
239 	case HAST_REPLICATION_MEMSYNC:
240 		nv_add_string(nvout, "memsync", "replication%u", no);
241 		break;
242 	case HAST_REPLICATION_ASYNC:
243 		nv_add_string(nvout, "async", "replication%u", no);
244 		break;
245 	default:
246 		nv_add_string(nvout, "unknown", "replication%u", no);
247 		break;
248 	}
249 	nv_add_string(nvout, role2str(res->hr_role), "role%u", no);
250 
251 	switch (res->hr_role) {
252 	case HAST_ROLE_PRIMARY:
253 		assert(res->hr_workerpid != 0);
254 		/* FALLTHROUGH */
255 	case HAST_ROLE_SECONDARY:
256 		if (res->hr_workerpid != 0)
257 			break;
258 		/* FALLTHROUGH */
259 	default:
260 		return;
261 	}
262 
263 	/*
264 	 * If we are here, it means that we have a worker process, which we
265 	 * want to ask some questions.
266 	 */
267 	control_status_worker(res, nvout, no);
268 }
269 
270 void
271 control_handle(struct hastd_config *cfg)
272 {
273 	struct proto_conn *conn;
274 	struct nv *nvin, *nvout;
275 	unsigned int ii;
276 	const char *str;
277 	uint8_t cmd, role;
278 	int error;
279 
280 	if (proto_accept(cfg->hc_controlconn, &conn) < 0) {
281 		pjdlog_errno(LOG_ERR, "Unable to accept control connection");
282 		return;
283 	}
284 
285 	cfg->hc_controlin = conn;
286 	nvin = nvout = NULL;
287 	role = HAST_ROLE_UNDEF;
288 
289 	if (hast_proto_recv_hdr(conn, &nvin) < 0) {
290 		pjdlog_errno(LOG_ERR, "Unable to receive control header");
291 		nvin = NULL;
292 		goto close;
293 	}
294 
295 	/* Obtain command code. 0 means that nv_get_uint8() failed. */
296 	cmd = nv_get_uint8(nvin, "cmd");
297 	if (cmd == 0) {
298 		pjdlog_error("Control header is missing 'cmd' field.");
299 		error = EHAST_INVALID;
300 		goto close;
301 	}
302 
303 	/* Allocate outgoing nv structure. */
304 	nvout = nv_alloc();
305 	if (nvout == NULL) {
306 		pjdlog_error("Unable to allocate header for control response.");
307 		error = EHAST_NOMEMORY;
308 		goto close;
309 	}
310 
311 	error = 0;
312 
313 	str = nv_get_string(nvin, "resource0");
314 	if (str == NULL) {
315 		pjdlog_error("Control header is missing 'resource0' field.");
316 		error = EHAST_INVALID;
317 		goto fail;
318 	}
319 	if (cmd == HASTCTL_SET_ROLE) {
320 		role = nv_get_uint8(nvin, "role");
321 		switch (role) {
322 		case HAST_ROLE_INIT:	/* Is that valid to set, hmm? */
323 		case HAST_ROLE_PRIMARY:
324 		case HAST_ROLE_SECONDARY:
325 			break;
326 		default:
327 			pjdlog_error("Invalid role received (%hhu).", role);
328 			error = EHAST_INVALID;
329 			goto fail;
330 		}
331 	}
332 	if (strcmp(str, "all") == 0) {
333 		struct hast_resource *res;
334 
335 		/* All configured resources. */
336 
337 		ii = 0;
338 		TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
339 			switch (cmd) {
340 			case HASTCTL_SET_ROLE:
341 				control_set_role_common(cfg, nvout, role, res,
342 				    res->hr_name, ii++);
343 				break;
344 			case HASTCTL_STATUS:
345 				control_status(cfg, nvout, res, res->hr_name,
346 				    ii++);
347 				break;
348 			default:
349 				pjdlog_error("Invalid command received (%hhu).",
350 				    cmd);
351 				error = EHAST_UNIMPLEMENTED;
352 				goto fail;
353 			}
354 		}
355 	} else {
356 		/* Only selected resources. */
357 
358 		for (ii = 0; ; ii++) {
359 			str = nv_get_string(nvin, "resource%u", ii);
360 			if (str == NULL)
361 				break;
362 			switch (cmd) {
363 			case HASTCTL_SET_ROLE:
364 				control_set_role_common(cfg, nvout, role, NULL,
365 				    str, ii);
366 				break;
367 			case HASTCTL_STATUS:
368 				control_status(cfg, nvout, NULL, str, ii);
369 				break;
370 			default:
371 				pjdlog_error("Invalid command received (%hhu).",
372 				    cmd);
373 				error = EHAST_UNIMPLEMENTED;
374 				goto fail;
375 			}
376 		}
377 	}
378 	if (nv_error(nvout) != 0)
379 		goto close;
380 fail:
381 	if (error != 0)
382 		nv_add_int16(nvout, error, "error");
383 
384 	if (hast_proto_send(NULL, conn, nvout, NULL, 0) < 0)
385 		pjdlog_errno(LOG_ERR, "Unable to send control response");
386 close:
387 	if (nvin != NULL)
388 		nv_free(nvin);
389 	if (nvout != NULL)
390 		nv_free(nvout);
391 	proto_close(conn);
392 	cfg->hc_controlin = NULL;
393 }
394 
395 /*
396  * Thread handles control requests from the parent.
397  */
398 void *
399 ctrl_thread(void *arg)
400 {
401 	struct hast_resource *res = arg;
402 	struct nv *nvin, *nvout;
403 	uint8_t cmd;
404 
405 	for (;;) {
406 		if (hast_proto_recv_hdr(res->hr_ctrl, &nvin) < 0) {
407 			if (sigexit_received)
408 				pthread_exit(NULL);
409 			pjdlog_errno(LOG_ERR,
410 			    "Unable to receive control message");
411 			kill(getpid(), SIGTERM);
412 			pthread_exit(NULL);
413 		}
414 		cmd = nv_get_uint8(nvin, "cmd");
415 		if (cmd == 0) {
416 			pjdlog_error("Control message is missing 'cmd' field.");
417 			nv_free(nvin);
418 			continue;
419 		}
420 		nvout = nv_alloc();
421 		switch (cmd) {
422 		case HASTCTL_STATUS:
423 			if (res->hr_remotein != NULL &&
424 			    res->hr_remoteout != NULL) {
425 				nv_add_string(nvout, "complete", "status");
426 			} else {
427 				nv_add_string(nvout, "degraded", "status");
428 			}
429 			nv_add_uint32(nvout, (uint32_t)res->hr_extentsize,
430 			    "extentsize");
431 			if (res->hr_role == HAST_ROLE_PRIMARY) {
432 				nv_add_uint32(nvout,
433 				    (uint32_t)res->hr_keepdirty, "keepdirty");
434 				nv_add_uint64(nvout,
435 				    (uint64_t)(activemap_ndirty(res->hr_amp) *
436 				    res->hr_extentsize), "dirty");
437 			} else {
438 				nv_add_uint32(nvout, (uint32_t)0, "keepdirty");
439 				nv_add_uint64(nvout, (uint64_t)0, "dirty");
440 			}
441 			nv_add_int16(nvout, 0, "error");
442 			break;
443 		case HASTCTL_RELOAD:
444 			/*
445 			 * When parent receives SIGHUP and discovers that
446 			 * something related to us has changes, it sends reload
447 			 * message to us.
448 			 */
449 			assert(res->hr_role == HAST_ROLE_PRIMARY);
450 			primary_config_reload(res, nvin);
451 			nv_add_int16(nvout, 0, "error");
452 			break;
453 		default:
454 			nv_add_int16(nvout, EINVAL, "error");
455 			break;
456 		}
457 		nv_free(nvin);
458 		if (nv_error(nvout) != 0) {
459 			pjdlog_error("Unable to create answer on control message.");
460 			nv_free(nvout);
461 			continue;
462 		}
463 		if (hast_proto_send(NULL, res->hr_ctrl, nvout, NULL, 0) < 0) {
464 			pjdlog_errno(LOG_ERR,
465 			    "Unable to send reply to control message");
466 		}
467 		nv_free(nvout);
468 	}
469 	/* NOTREACHED */
470 	return (NULL);
471 }
472