control.c revision 210882 
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: head/sbin/hastd/control.c 210882 2010-08-05 19:04:29Z pjd $");
32
33#include <sys/types.h>
34#include <sys/wait.h>
35#include <signal.h>
36
37#include <assert.h>
38#include <errno.h>
39#include <pthread.h>
40#include <stdio.h>
41#include <string.h>
42
43#include "hast.h"
44#include "hastd.h"
45#include "hast_proto.h"
46#include "nv.h"
47#include "pjdlog.h"
48#include "proto.h"
49#include "subr.h"
50
51#include "control.h"
52
53static void
54control_set_role_common(struct hastd_config *cfg, struct nv *nvout,
55    uint8_t role, struct hast_resource *res, const char *name, unsigned int no)
56{
57
58	/* Name is always needed. */
59	if (name != NULL)
60		nv_add_string(nvout, name, "resource%u", no);
61
62	if (res == NULL) {
63		assert(cfg != NULL);
64		assert(name != NULL);
65
66		TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
67			if (strcmp(res->hr_name, name) == 0)
68				break;
69		}
70		if (res == NULL) {
71			nv_add_int16(nvout, EHAST_NOENTRY, "error%u", no);
72			return;
73		}
74	}
75	assert(res != NULL);
76
77	/* Send previous role back. */
78	nv_add_string(nvout, role2str(res->hr_role), "role%u", no);
79
80	/* Nothing changed, return here. */
81	if (role == res->hr_role)
82		return;
83
84	pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
85	pjdlog_info("Role changed to %s.", role2str(role));
86
87	/* Change role to the new one. */
88	res->hr_role = role;
89	pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
90
91	/*
92	 * If previous role was primary or secondary we have to kill process
93	 * doing that work.
94	 */
95	if (res->hr_workerpid != 0) {
96		if (kill(res->hr_workerpid, SIGTERM) < 0) {
97			pjdlog_errno(LOG_WARNING,
98			    "Unable to kill worker process %u",
99			    (unsigned int)res->hr_workerpid);
100		} else if (waitpid(res->hr_workerpid, NULL, 0) !=
101		    res->hr_workerpid) {
102			pjdlog_errno(LOG_WARNING,
103			    "Error while waiting for worker process %u",
104			    (unsigned int)res->hr_workerpid);
105		} else {
106			pjdlog_debug(1, "Worker process %u stopped.",
107			    (unsigned int)res->hr_workerpid);
108		}
109		res->hr_workerpid = 0;
110	}
111
112	/* Start worker process if we are changing to primary. */
113	if (role == HAST_ROLE_PRIMARY)
114		hastd_primary(res);
115	pjdlog_prefix_set("%s", "");
116}
117
118void
119control_set_role(struct hast_resource *res, uint8_t role)
120{
121
122	control_set_role_common(NULL, NULL, role, res, NULL, 0);
123}
124
125static void
126control_status_worker(struct hast_resource *res, struct nv *nvout,
127    unsigned int no)
128{
129	struct nv *cnvin, *cnvout;
130	const char *str;
131	int error;
132
133	cnvin = cnvout = NULL;
134	error = 0;
135
136	/*
137	 * Prepare and send command to worker process.
138	 */
139	cnvout = nv_alloc();
140	nv_add_uint8(cnvout, HASTCTL_STATUS, "cmd");
141	error = nv_error(cnvout);
142	if (error != 0) {
143		/* LOG */
144		goto end;
145	}
146	if (hast_proto_send(res, res->hr_ctrl, cnvout, NULL, 0) < 0) {
147		error = errno;
148		/* LOG */
149		goto end;
150	}
151
152	/*
153	 * Receive response.
154	 */
155	if (hast_proto_recv_hdr(res->hr_ctrl, &cnvin) < 0) {
156		error = errno;
157		/* LOG */
158		goto end;
159	}
160
161	error = nv_get_int64(cnvin, "error");
162	if (error != 0)
163		goto end;
164
165	if ((str = nv_get_string(cnvin, "status")) == NULL) {
166		error = ENOENT;
167		/* LOG */
168		goto end;
169	}
170	nv_add_string(nvout, str, "status%u", no);
171	nv_add_uint64(nvout, nv_get_uint64(cnvin, "dirty"), "dirty%u", no);
172	nv_add_uint32(nvout, nv_get_uint32(cnvin, "extentsize"),
173	    "extentsize%u", no);
174	nv_add_uint32(nvout, nv_get_uint32(cnvin, "keepdirty"),
175	    "keepdirty%u", no);
176end:
177	if (cnvin != NULL)
178		nv_free(cnvin);
179	if (cnvout != NULL)
180		nv_free(cnvout);
181	if (error != 0)
182		nv_add_int16(nvout, error, "error");
183}
184
185static void
186control_status(struct hastd_config *cfg, struct nv *nvout,
187    struct hast_resource *res, const char *name, unsigned int no)
188{
189
190	assert(cfg != NULL);
191	assert(nvout != NULL);
192	assert(name != NULL);
193
194	/* Name is always needed. */
195	nv_add_string(nvout, name, "resource%u", no);
196
197	if (res == NULL) {
198		TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
199			if (strcmp(res->hr_name, name) == 0)
200				break;
201		}
202		if (res == NULL) {
203			nv_add_int16(nvout, EHAST_NOENTRY, "error%u", no);
204			return;
205		}
206	}
207	assert(res != NULL);
208	nv_add_string(nvout, res->hr_provname, "provname%u", no);
209	nv_add_string(nvout, res->hr_localpath, "localpath%u", no);
210	nv_add_string(nvout, res->hr_remoteaddr, "remoteaddr%u", no);
211	switch (res->hr_replication) {
212	case HAST_REPLICATION_FULLSYNC:
213		nv_add_string(nvout, "fullsync", "replication%u", no);
214		break;
215	case HAST_REPLICATION_MEMSYNC:
216		nv_add_string(nvout, "memsync", "replication%u", no);
217		break;
218	case HAST_REPLICATION_ASYNC:
219		nv_add_string(nvout, "async", "replication%u", no);
220		break;
221	default:
222		nv_add_string(nvout, "unknown", "replication%u", no);
223		break;
224	}
225	nv_add_string(nvout, role2str(res->hr_role), "role%u", no);
226
227	switch (res->hr_role) {
228	case HAST_ROLE_PRIMARY:
229		assert(res->hr_workerpid != 0);
230		/* FALLTHROUGH */
231	case HAST_ROLE_SECONDARY:
232		if (res->hr_workerpid != 0)
233			break;
234		/* FALLTHROUGH */
235	default:
236		return;
237	}
238
239	/*
240	 * If we are here, it means that we have a worker process, which we
241	 * want to ask some questions.
242	 */
243	control_status_worker(res, nvout, no);
244}
245
246void
247control_handle(struct hastd_config *cfg)
248{
249	struct proto_conn *conn;
250	struct nv *nvin, *nvout;
251	unsigned int ii;
252	const char *str;
253	uint8_t cmd, role;
254	int error;
255
256	if (proto_accept(cfg->hc_controlconn, &conn) < 0) {
257		pjdlog_errno(LOG_ERR, "Unable to accept control connection");
258		return;
259	}
260
261	nvin = nvout = NULL;
262	role = HAST_ROLE_UNDEF;
263
264	if (hast_proto_recv_hdr(conn, &nvin) < 0) {
265		pjdlog_errno(LOG_ERR, "Unable to receive control header");
266		nvin = NULL;
267		goto close;
268	}
269
270	/* Obtain command code. 0 means that nv_get_uint8() failed. */
271	cmd = nv_get_uint8(nvin, "cmd");
272	if (cmd == 0) {
273		pjdlog_error("Control header is missing 'cmd' field.");
274		error = EHAST_INVALID;
275		goto close;
276	}
277
278	/* Allocate outgoing nv structure. */
279	nvout = nv_alloc();
280	if (nvout == NULL) {
281		pjdlog_error("Unable to allocate header for control response.");
282		error = EHAST_NOMEMORY;
283		goto close;
284	}
285
286	error = 0;
287
288	str = nv_get_string(nvin, "resource0");
289	if (str == NULL) {
290		pjdlog_error("Control header is missing 'resource0' field.");
291		error = EHAST_INVALID;
292		goto fail;
293	}
294	if (cmd == HASTCTL_SET_ROLE) {
295		role = nv_get_uint8(nvin, "role");
296		switch (role) {
297		case HAST_ROLE_INIT:	/* Is that valid to set, hmm? */
298		case HAST_ROLE_PRIMARY:
299		case HAST_ROLE_SECONDARY:
300			break;
301		default:
302			pjdlog_error("Invalid role received (%hhu).", role);
303			error = EHAST_INVALID;
304			goto fail;
305		}
306	}
307	if (strcmp(str, "all") == 0) {
308		struct hast_resource *res;
309
310		/* All configured resources. */
311
312		ii = 0;
313		TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
314			switch (cmd) {
315			case HASTCTL_SET_ROLE:
316				control_set_role_common(cfg, nvout, role, res,
317				    res->hr_name, ii++);
318				break;
319			case HASTCTL_STATUS:
320				control_status(cfg, nvout, res, res->hr_name,
321				    ii++);
322				break;
323			default:
324				pjdlog_error("Invalid command received (%hhu).",
325				    cmd);
326				error = EHAST_UNIMPLEMENTED;
327				goto fail;
328			}
329		}
330	} else {
331		/* Only selected resources. */
332
333		for (ii = 0; ; ii++) {
334			str = nv_get_string(nvin, "resource%u", ii);
335			if (str == NULL)
336				break;
337			switch (cmd) {
338			case HASTCTL_SET_ROLE:
339				control_set_role_common(cfg, nvout, role, NULL,
340				    str, ii);
341				break;
342			case HASTCTL_STATUS:
343				control_status(cfg, nvout, NULL, str, ii);
344				break;
345			default:
346				pjdlog_error("Invalid command received (%hhu).",
347				    cmd);
348				error = EHAST_UNIMPLEMENTED;
349				goto fail;
350			}
351		}
352	}
353	if (nv_error(nvout) != 0)
354		goto close;
355fail:
356	if (error != 0)
357		nv_add_int16(nvout, error, "error");
358
359	if (hast_proto_send(NULL, conn, nvout, NULL, 0) < 0)
360		pjdlog_errno(LOG_ERR, "Unable to send control response");
361close:
362	if (nvin != NULL)
363		nv_free(nvin);
364	if (nvout != NULL)
365		nv_free(nvout);
366	proto_close(conn);
367}
368
369/*
370 * Thread handles control requests from the parent.
371 */
372void *
373ctrl_thread(void *arg)
374{
375	struct hast_resource *res = arg;
376	struct nv *nvin, *nvout;
377	uint8_t cmd;
378
379	for (;;) {
380		if (hast_proto_recv_hdr(res->hr_ctrl, &nvin) < 0) {
381			if (sigexit_received)
382				pthread_exit(NULL);
383			pjdlog_errno(LOG_ERR,
384			    "Unable to receive control message");
385			continue;
386		}
387		cmd = nv_get_uint8(nvin, "cmd");
388		if (cmd == 0) {
389			pjdlog_error("Control message is missing 'cmd' field.");
390			nv_free(nvin);
391			continue;
392		}
393		nv_free(nvin);
394		nvout = nv_alloc();
395		switch (cmd) {
396		case HASTCTL_STATUS:
397			if (res->hr_remotein != NULL &&
398			    res->hr_remoteout != NULL) {
399				nv_add_string(nvout, "complete", "status");
400			} else {
401				nv_add_string(nvout, "degraded", "status");
402			}
403			nv_add_uint32(nvout, (uint32_t)res->hr_extentsize,
404			    "extentsize");
405			if (res->hr_role == HAST_ROLE_PRIMARY) {
406				nv_add_uint32(nvout,
407				    (uint32_t)res->hr_keepdirty, "keepdirty");
408				nv_add_uint64(nvout,
409				    (uint64_t)(activemap_ndirty(res->hr_amp) *
410				    res->hr_extentsize), "dirty");
411			} else {
412				nv_add_uint32(nvout, (uint32_t)0, "keepdirty");
413				nv_add_uint64(nvout, (uint64_t)0, "dirty");
414			}
415			break;
416		default:
417			nv_add_int16(nvout, EINVAL, "error");
418			break;
419		}
420		if (nv_error(nvout) != 0) {
421			pjdlog_error("Unable to create answer on control message.");
422			nv_free(nvout);
423			continue;
424		}
425		if (hast_proto_send(NULL, res->hr_ctrl, nvout, NULL, 0) < 0) {
426			pjdlog_errno(LOG_ERR,
427			    "Unable to send reply to control message");
428		}
429		nv_free(nvout);
430	}
431	/* NOTREACHED */
432	return (NULL);
433}
434