1/*-
2 * Copyright (c) 2011, 2012, 2013, 2014, 2015, 2016  Spectra Logic Corporation
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions, and the following disclaimer,
10 *    without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 *    substantially similar to the "NO WARRANTY" disclaimer below
13 *    ("Disclaimer") and any redistribution must be conditioned upon
14 *    including a substantially similar Disclaimer requirement for further
15 *    binary redistribution.
16 *
17 * NO WARRANTY
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGES.
29 *
30 * Authors: Justin T. Gibbs     (Spectra Logic Corporation)
31 */
32
33/**
34 * \file zfsd.cc
35 *
36 * The ZFS daemon consumes kernel devdctl(4) event data via devd(8)'s
37 * unix domain socket in order to react to system changes that impact
38 * the function of ZFS storage pools.  The goal of this daemon is to
39 * provide similar functionality to the Solaris ZFS Diagnostic Engine
40 * (zfs-diagnosis), the Solaris ZFS fault handler (zfs-retire), and
41 * the Solaris ZFS vdev insertion agent (zfs-mod sysevent handler).
42 */
43
44#include <sys/cdefs.h>
45#include <sys/byteorder.h>
46#include <sys/param.h>
47#include <sys/fs/zfs.h>
48
49#include <err.h>
50#include <fcntl.h>
51#include <libgeom.h>
52#include <libutil.h>
53#include <poll.h>
54#include <syslog.h>
55
56#include <libzfs.h>
57
58#include <list>
59#include <map>
60#include <string>
61
62#include <devdctl/guid.h>
63#include <devdctl/event.h>
64#include <devdctl/event_factory.h>
65#include <devdctl/exception.h>
66#include <devdctl/consumer.h>
67
68#include "callout.h"
69#include "vdev_iterator.h"
70#include "zfsd_event.h"
71#include "case_file.h"
72#include "vdev.h"
73#include "vdev_iterator.h"
74#include "zfsd.h"
75#include "zfsd_exception.h"
76#include "zpool_list.h"
77
78__FBSDID("$FreeBSD$");
79
80/*================================== Macros ==================================*/
81#define NUM_ELEMENTS(x) (sizeof(x) / sizeof(*x))
82
83/*============================ Namespace Control =============================*/
84using DevdCtl::Event;
85using DevdCtl::EventFactory;
86using DevdCtl::EventList;
87
88/*================================ Global Data ===============================*/
89int              g_debug = 0;
90libzfs_handle_t *g_zfsHandle;
91
92/*--------------------------------- ZfsDaemon --------------------------------*/
93//- ZfsDaemon Static Private Data ----------------------------------------------
94ZfsDaemon	    *ZfsDaemon::s_theZfsDaemon;
95bool		     ZfsDaemon::s_logCaseFiles;
96bool		     ZfsDaemon::s_terminateEventLoop;
97char		     ZfsDaemon::s_pidFilePath[] = "/var/run/zfsd.pid";
98pidfh		    *ZfsDaemon::s_pidFH;
99int		     ZfsDaemon::s_signalPipeFD[2];
100bool		     ZfsDaemon::s_systemRescanRequested(false);
101EventFactory::Record ZfsDaemon::s_registryEntries[] =
102{
103	{ Event::NOTIFY, "GEOM",  &GeomEvent::Builder },
104	{ Event::NOTIFY, "ZFS",   &ZfsEvent::Builder }
105};
106
107//- ZfsDaemon Static Public Methods --------------------------------------------
108ZfsDaemon &
109ZfsDaemon::Get()
110{
111	return (*s_theZfsDaemon);
112}
113
114void
115ZfsDaemon::WakeEventLoop()
116{
117	write(s_signalPipeFD[1], "+", 1);
118}
119
120void
121ZfsDaemon::RequestSystemRescan()
122{
123	s_systemRescanRequested = true;
124	ZfsDaemon::WakeEventLoop();
125}
126
127void
128ZfsDaemon::Run()
129{
130	ZfsDaemon daemon;
131
132	while (s_terminateEventLoop == false) {
133
134		try {
135			daemon.DisconnectFromDevd();
136
137			if (daemon.ConnectToDevd() == false) {
138				sleep(30);
139				continue;
140			}
141
142			daemon.DetectMissedEvents();
143
144			daemon.EventLoop();
145
146		} catch (const DevdCtl::Exception &exp) {
147			exp.Log();
148		}
149	}
150
151	daemon.DisconnectFromDevd();
152}
153
154//- ZfsDaemon Private Methods --------------------------------------------------
155ZfsDaemon::ZfsDaemon()
156 : Consumer(/*defBuilder*/NULL, s_registryEntries,
157	    NUM_ELEMENTS(s_registryEntries))
158{
159	if (s_theZfsDaemon != NULL)
160		errx(1, "Multiple ZfsDaemon instances created. Exiting");
161
162	s_theZfsDaemon = this;
163
164	if (pipe(s_signalPipeFD) != 0)
165		errx(1, "Unable to allocate signal pipe. Exiting");
166
167	if (fcntl(s_signalPipeFD[0], F_SETFL, O_NONBLOCK) == -1)
168		errx(1, "Unable to set pipe as non-blocking. Exiting");
169
170	if (fcntl(s_signalPipeFD[1], F_SETFL, O_NONBLOCK) == -1)
171		errx(1, "Unable to set pipe as non-blocking. Exiting");
172
173	signal(SIGHUP,  ZfsDaemon::RescanSignalHandler);
174	signal(SIGINFO, ZfsDaemon::InfoSignalHandler);
175	signal(SIGINT,  ZfsDaemon::QuitSignalHandler);
176	signal(SIGTERM, ZfsDaemon::QuitSignalHandler);
177	signal(SIGUSR1, ZfsDaemon::RescanSignalHandler);
178
179	g_zfsHandle = libzfs_init();
180	if (g_zfsHandle == NULL)
181		errx(1, "Unable to initialize ZFS library. Exiting");
182
183	Callout::Init();
184	InitializeSyslog();
185	OpenPIDFile();
186
187	if (g_debug == 0)
188		daemon(0, 0);
189
190	UpdatePIDFile();
191}
192
193ZfsDaemon::~ZfsDaemon()
194{
195	PurgeCaseFiles();
196	ClosePIDFile();
197}
198
199void
200ZfsDaemon::PurgeCaseFiles()
201{
202	CaseFile::PurgeAll();
203}
204
205bool
206ZfsDaemon::VdevAddCaseFile(Vdev &vdev, void *cbArg)
207{
208	if (vdev.State() != VDEV_STATE_HEALTHY)
209		CaseFile::Create(vdev);
210
211	return (/*break early*/false);
212}
213
214void
215ZfsDaemon::BuildCaseFiles()
216{
217	ZpoolList zpl;
218	ZpoolList::iterator pool;
219
220	/* Add CaseFiles for vdevs with issues. */
221	for (pool = zpl.begin(); pool != zpl.end(); pool++)
222		VdevIterator(*pool).Each(VdevAddCaseFile, NULL);
223
224	/* De-serialize any saved cases. */
225	CaseFile::DeSerialize();
226
227	/* Simulate config_sync events to force CaseFile reevaluation */
228	for (pool = zpl.begin(); pool != zpl.end(); pool++) {
229		char evString[160];
230		Event *event;
231		nvlist_t *config;
232		uint64_t poolGUID;
233		const char *poolname;
234
235		poolname = zpool_get_name(*pool);
236		config = zpool_get_config(*pool, NULL);
237		if (config == NULL) {
238			syslog(LOG_ERR, "ZFSDaemon::BuildCaseFiles: Could not "
239			    "find pool config for pool %s", poolname);
240			continue;
241		}
242		if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
243				     &poolGUID) != 0) {
244			syslog(LOG_ERR, "ZFSDaemon::BuildCaseFiles: Could not "
245			    "find pool guid for pool %s", poolname);
246			continue;
247		}
248
249
250		snprintf(evString, 160, "!system=ZFS subsystem=ZFS "
251		    "type=misc.fs.zfs.config_sync sub_type=synthesized "
252		    "pool_name=%s pool_guid=%" PRIu64 "\n", poolname, poolGUID);
253		event = Event::CreateEvent(GetFactory(), string(evString));
254		if (event != NULL) {
255			event->Process();
256			delete event;
257		}
258	}
259}
260
261void
262ZfsDaemon::RescanSystem()
263{
264        struct gmesh	  mesh;
265        struct gclass	 *mp;
266        struct ggeom	 *gp;
267        struct gprovider *pp;
268	int		  result;
269
270        /*
271	 * The devdctl system doesn't replay events for new consumers
272	 * of the interface.  Emit manufactured DEVFS arrival events
273	 * for any devices that already before we started or during
274	 * periods where we've lost our connection to devd.
275         */
276	result = geom_gettree(&mesh);
277	if (result != 0) {
278		syslog(LOG_ERR, "ZfsDaemon::RescanSystem: "
279		       "geom_gettree faild with error %d\n", result);
280		return;
281	}
282
283	const string evStart("!system=DEVFS subsystem=CDEV type=CREATE "
284			     "sub_type=synthesized cdev=");
285        LIST_FOREACH(mp, &mesh.lg_class, lg_class) {
286                LIST_FOREACH(gp, &mp->lg_geom, lg_geom) {
287                        LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
288				Event *event;
289
290				string evString(evStart + pp->lg_name + "\n");
291				event = Event::CreateEvent(GetFactory(),
292							   evString);
293				if (event != NULL) {
294					if (event->Process())
295						SaveEvent(*event);
296					delete event;
297				}
298                        }
299                }
300	}
301	geom_deletetree(&mesh);
302}
303
304void
305ZfsDaemon::DetectMissedEvents()
306{
307	do {
308		PurgeCaseFiles();
309
310		/*
311		 * Discard any events waiting for us.  We don't know
312		 * if they still apply to the current state of the
313		 * system.
314		 */
315		FlushEvents();
316
317		BuildCaseFiles();
318
319		/*
320		 * If the system state has changed during our
321		 * interrogation, start over.
322		 */
323	} while (s_terminateEventLoop == false && EventsPending());
324
325	RescanSystem();
326}
327
328void
329ZfsDaemon::EventLoop()
330{
331	while (s_terminateEventLoop == false) {
332		struct pollfd fds[2];
333		int	      result;
334
335		if (s_logCaseFiles == true) {
336			EventList::iterator event(m_unconsumedEvents.begin());
337			s_logCaseFiles = false;
338			CaseFile::LogAll();
339			while (event != m_unconsumedEvents.end())
340				(*event++)->Log(LOG_INFO);
341		}
342
343		Callout::ExpireCallouts();
344
345		/* Wait for data. */
346		fds[0].fd      = m_devdSockFD;
347		fds[0].events  = POLLIN;
348		fds[0].revents = 0;
349		fds[1].fd      = s_signalPipeFD[0];
350		fds[1].events  = POLLIN;
351		fds[1].revents = 0;
352		result = poll(fds, NUM_ELEMENTS(fds), /*timeout*/INFTIM);
353		if (result == -1) {
354			if (errno == EINTR)
355				continue;
356			else
357				err(1, "Polling for devd events failed");
358		} else if (result == 0) {
359			errx(1, "Unexpected result of 0 from poll. Exiting");
360		}
361
362		if ((fds[0].revents & POLLIN) != 0)
363			ProcessEvents();
364
365		if ((fds[1].revents & POLLIN) != 0) {
366			static char discardBuf[128];
367
368			/*
369			 * This pipe exists just to close the signal
370			 * race.  Its contents are of no interest to
371			 * us, but we must ensure that future signals
372			 * have space in the pipe to write.
373			 */
374			while (read(s_signalPipeFD[0], discardBuf,
375				    sizeof(discardBuf)) > 0)
376				;
377		}
378
379		if (s_systemRescanRequested == true) {
380			s_systemRescanRequested = false;
381			syslog(LOG_INFO, "System Rescan request processed.");
382			RescanSystem();
383		}
384
385		if ((fds[0].revents & POLLERR) != 0) {
386			syslog(LOG_INFO, "POLLERROR detected on devd socket.");
387			break;
388		}
389
390		if ((fds[0].revents & POLLHUP) != 0) {
391			syslog(LOG_INFO, "POLLHUP detected on devd socket.");
392			break;
393		}
394	}
395}
396//- ZfsDaemon staic Private Methods --------------------------------------------
397void
398ZfsDaemon::InfoSignalHandler(int)
399{
400	s_logCaseFiles = true;
401	ZfsDaemon::WakeEventLoop();
402}
403
404void
405ZfsDaemon::RescanSignalHandler(int)
406{
407	RequestSystemRescan();
408}
409
410void
411ZfsDaemon::QuitSignalHandler(int)
412{
413	s_terminateEventLoop = true;
414	ZfsDaemon::WakeEventLoop();
415}
416
417void
418ZfsDaemon::OpenPIDFile()
419{
420	pid_t otherPID;
421
422	s_pidFH = pidfile_open(s_pidFilePath, 0600, &otherPID);
423	if (s_pidFH == NULL) {
424		if (errno == EEXIST)
425			errx(1, "already running as PID %d. Exiting", otherPID);
426		warn("cannot open PID file");
427	}
428}
429
430void
431ZfsDaemon::UpdatePIDFile()
432{
433	if (s_pidFH != NULL)
434		pidfile_write(s_pidFH);
435}
436
437void
438ZfsDaemon::ClosePIDFile()
439{
440	if (s_pidFH != NULL)
441		pidfile_remove(s_pidFH);
442}
443
444void
445ZfsDaemon::InitializeSyslog()
446{
447	openlog("zfsd", LOG_NDELAY, LOG_DAEMON);
448}
449
450