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/param.h>
46#include <sys/fs/zfs.h>
47
48#include <err.h>
49#include <libgeom.h>
50#include <libutil.h>
51#include <poll.h>
52#include <syslog.h>
53
54#include <libzfs.h>
55
56#include <list>
57#include <map>
58#include <string>
59
60#include <devdctl/guid.h>
61#include <devdctl/event.h>
62#include <devdctl/event_factory.h>
63#include <devdctl/exception.h>
64#include <devdctl/consumer.h>
65
66#include "callout.h"
67#include "vdev_iterator.h"
68#include "zfsd_event.h"
69#include "case_file.h"
70#include "vdev.h"
71#include "vdev_iterator.h"
72#include "zfsd.h"
73#include "zfsd_exception.h"
74#include "zpool_list.h"
75
76__FBSDID("$FreeBSD$");
77
78/*================================== Macros ==================================*/
79#define NUM_ELEMENTS(x) (sizeof(x) / sizeof(*x))
80
81/*============================ Namespace Control =============================*/
82using DevdCtl::Event;
83using DevdCtl::EventFactory;
84using DevdCtl::EventList;
85
86/*================================ Global Data ===============================*/
87int              g_debug = 0;
88libzfs_handle_t *g_zfsHandle;
89
90/*--------------------------------- ZfsDaemon --------------------------------*/
91//- ZfsDaemon Static Private Data ----------------------------------------------
92ZfsDaemon	    *ZfsDaemon::s_theZfsDaemon;
93bool		     ZfsDaemon::s_logCaseFiles;
94bool		     ZfsDaemon::s_terminateEventLoop;
95char		     ZfsDaemon::s_pidFilePath[] = "/var/run/zfsd.pid";
96pidfh		    *ZfsDaemon::s_pidFH;
97int		     ZfsDaemon::s_signalPipeFD[2];
98bool		     ZfsDaemon::s_systemRescanRequested(false);
99EventFactory::Record ZfsDaemon::s_registryEntries[] =
100{
101	{ Event::NOTIFY, "GEOM",  &GeomEvent::Builder },
102	{ Event::NOTIFY, "ZFS",   &ZfsEvent::Builder }
103};
104
105//- ZfsDaemon Static Public Methods --------------------------------------------
106ZfsDaemon &
107ZfsDaemon::Get()
108{
109	return (*s_theZfsDaemon);
110}
111
112void
113ZfsDaemon::WakeEventLoop()
114{
115	write(s_signalPipeFD[1], "+", 1);
116}
117
118void
119ZfsDaemon::RequestSystemRescan()
120{
121	s_systemRescanRequested = true;
122	ZfsDaemon::WakeEventLoop();
123}
124
125void
126ZfsDaemon::Run()
127{
128	ZfsDaemon daemon;
129
130	while (s_terminateEventLoop == false) {
131
132		try {
133			daemon.DisconnectFromDevd();
134
135			if (daemon.ConnectToDevd() == false) {
136				sleep(30);
137				continue;
138			}
139
140			daemon.DetectMissedEvents();
141
142			daemon.EventLoop();
143
144		} catch (const DevdCtl::Exception &exp) {
145			exp.Log();
146		}
147	}
148
149	daemon.DisconnectFromDevd();
150}
151
152//- ZfsDaemon Private Methods --------------------------------------------------
153ZfsDaemon::ZfsDaemon()
154 : Consumer(/*defBuilder*/NULL, s_registryEntries,
155	    NUM_ELEMENTS(s_registryEntries))
156{
157	if (s_theZfsDaemon != NULL)
158		errx(1, "Multiple ZfsDaemon instances created. Exiting");
159
160	s_theZfsDaemon = this;
161
162	if (pipe(s_signalPipeFD) != 0)
163		errx(1, "Unable to allocate signal pipe. Exiting");
164
165	if (fcntl(s_signalPipeFD[0], F_SETFL, O_NONBLOCK) == -1)
166		errx(1, "Unable to set pipe as non-blocking. Exiting");
167
168	if (fcntl(s_signalPipeFD[1], F_SETFL, O_NONBLOCK) == -1)
169		errx(1, "Unable to set pipe as non-blocking. Exiting");
170
171	signal(SIGHUP,  ZfsDaemon::RescanSignalHandler);
172	signal(SIGINFO, ZfsDaemon::InfoSignalHandler);
173	signal(SIGINT,  ZfsDaemon::QuitSignalHandler);
174	signal(SIGTERM, ZfsDaemon::QuitSignalHandler);
175	signal(SIGUSR1, ZfsDaemon::RescanSignalHandler);
176
177	g_zfsHandle = libzfs_init();
178	if (g_zfsHandle == NULL)
179		errx(1, "Unable to initialize ZFS library. Exiting");
180
181	Callout::Init();
182	InitializeSyslog();
183	OpenPIDFile();
184
185	if (g_debug == 0)
186		daemon(0, 0);
187
188	UpdatePIDFile();
189}
190
191ZfsDaemon::~ZfsDaemon()
192{
193	PurgeCaseFiles();
194	ClosePIDFile();
195}
196
197void
198ZfsDaemon::PurgeCaseFiles()
199{
200	CaseFile::PurgeAll();
201}
202
203bool
204ZfsDaemon::VdevAddCaseFile(Vdev &vdev, void *cbArg)
205{
206	if (vdev.State() != VDEV_STATE_HEALTHY)
207		CaseFile::Create(vdev);
208
209	return (/*break early*/false);
210}
211
212void
213ZfsDaemon::BuildCaseFiles()
214{
215	ZpoolList zpl;
216	ZpoolList::iterator pool;
217
218	/* Add CaseFiles for vdevs with issues. */
219	for (pool = zpl.begin(); pool != zpl.end(); pool++)
220		VdevIterator(*pool).Each(VdevAddCaseFile, NULL);
221
222	/* De-serialize any saved cases. */
223	CaseFile::DeSerialize();
224
225	/* Simulate config_sync events to force CaseFile reevaluation */
226	for (pool = zpl.begin(); pool != zpl.end(); pool++) {
227		char evString[160];
228		Event *event;
229		nvlist_t *config;
230		uint64_t poolGUID;
231		const char *poolname;
232
233		poolname = zpool_get_name(*pool);
234		config = zpool_get_config(*pool, NULL);
235		if (config == NULL) {
236			syslog(LOG_ERR, "ZFSDaemon::BuildCaseFiles: Could not "
237			    "find pool config for pool %s", poolname);
238			continue;
239		}
240		if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
241				     &poolGUID) != 0) {
242			syslog(LOG_ERR, "ZFSDaemon::BuildCaseFiles: Could not "
243			    "find pool guid for pool %s", poolname);
244			continue;
245		}
246
247
248		snprintf(evString, 160, "!system=ZFS subsystem=ZFS "
249		    "type=misc.fs.zfs.config_sync sub_type=synthesized "
250		    "pool_name=%s pool_guid=%" PRIu64 "\n", poolname, poolGUID);
251		event = Event::CreateEvent(GetFactory(), string(evString));
252		if (event != NULL) {
253			event->Process();
254			delete event;
255		}
256	}
257}
258
259void
260ZfsDaemon::RescanSystem()
261{
262        struct gmesh	  mesh;
263        struct gclass	 *mp;
264        struct ggeom	 *gp;
265        struct gprovider *pp;
266	int		  result;
267
268        /*
269	 * The devdctl system doesn't replay events for new consumers
270	 * of the interface.  Emit manufactured DEVFS arrival events
271	 * for any devices that already before we started or during
272	 * periods where we've lost our connection to devd.
273         */
274	result = geom_gettree(&mesh);
275	if (result != 0) {
276		syslog(LOG_ERR, "ZfsDaemon::RescanSystem: "
277		       "geom_gettree faild with error %d\n", result);
278		return;
279	}
280
281	const string evStart("!system=DEVFS subsystem=CDEV type=CREATE "
282			     "sub_type=synthesized cdev=");
283        LIST_FOREACH(mp, &mesh.lg_class, lg_class) {
284                LIST_FOREACH(gp, &mp->lg_geom, lg_geom) {
285                        LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
286				Event *event;
287
288				string evString(evStart + pp->lg_name + "\n");
289				event = Event::CreateEvent(GetFactory(),
290							   evString);
291				if (event != NULL) {
292					if (event->Process())
293						SaveEvent(*event);
294					delete event;
295				}
296                        }
297                }
298	}
299	geom_deletetree(&mesh);
300}
301
302void
303ZfsDaemon::DetectMissedEvents()
304{
305	do {
306		PurgeCaseFiles();
307
308		/*
309		 * Discard any events waiting for us.  We don't know
310		 * if they still apply to the current state of the
311		 * system.
312		 */
313		FlushEvents();
314
315		BuildCaseFiles();
316
317		/*
318		 * If the system state has changed during our
319		 * interrogation, start over.
320		 */
321	} while (s_terminateEventLoop == false && EventsPending());
322
323	RescanSystem();
324}
325
326void
327ZfsDaemon::EventLoop()
328{
329	while (s_terminateEventLoop == false) {
330		struct pollfd fds[2];
331		int	      result;
332
333		if (s_logCaseFiles == true) {
334			EventList::iterator event(m_unconsumedEvents.begin());
335			s_logCaseFiles = false;
336			CaseFile::LogAll();
337			while (event != m_unconsumedEvents.end())
338				(*event++)->Log(LOG_INFO);
339		}
340
341		Callout::ExpireCallouts();
342
343		/* Wait for data. */
344		fds[0].fd      = m_devdSockFD;
345		fds[0].events  = POLLIN;
346		fds[0].revents = 0;
347		fds[1].fd      = s_signalPipeFD[0];
348		fds[1].events  = POLLIN;
349		fds[1].revents = 0;
350		result = poll(fds, NUM_ELEMENTS(fds), /*timeout*/INFTIM);
351		if (result == -1) {
352			if (errno == EINTR)
353				continue;
354			else
355				err(1, "Polling for devd events failed");
356		} else if (result == 0) {
357			errx(1, "Unexpected result of 0 from poll. Exiting");
358		}
359
360		if ((fds[0].revents & POLLIN) != 0)
361			ProcessEvents();
362
363		if ((fds[1].revents & POLLIN) != 0) {
364			static char discardBuf[128];
365
366			/*
367			 * This pipe exists just to close the signal
368			 * race.  Its contents are of no interest to
369			 * us, but we must ensure that future signals
370			 * have space in the pipe to write.
371			 */
372			while (read(s_signalPipeFD[0], discardBuf,
373				    sizeof(discardBuf)) > 0)
374				;
375		}
376
377		if (s_systemRescanRequested == true) {
378			s_systemRescanRequested = false;
379			syslog(LOG_INFO, "System Rescan request processed.");
380			RescanSystem();
381		}
382
383		if ((fds[0].revents & POLLERR) != 0) {
384			syslog(LOG_INFO, "POLLERROR detected on devd socket.");
385			break;
386		}
387
388		if ((fds[0].revents & POLLHUP) != 0) {
389			syslog(LOG_INFO, "POLLHUP detected on devd socket.");
390			break;
391		}
392	}
393}
394//- ZfsDaemon staic Private Methods --------------------------------------------
395void
396ZfsDaemon::InfoSignalHandler(int)
397{
398	s_logCaseFiles = true;
399	ZfsDaemon::WakeEventLoop();
400}
401
402void
403ZfsDaemon::RescanSignalHandler(int)
404{
405	RequestSystemRescan();
406}
407
408void
409ZfsDaemon::QuitSignalHandler(int)
410{
411	s_terminateEventLoop = true;
412	ZfsDaemon::WakeEventLoop();
413}
414
415void
416ZfsDaemon::OpenPIDFile()
417{
418	pid_t otherPID;
419
420	s_pidFH = pidfile_open(s_pidFilePath, 0600, &otherPID);
421	if (s_pidFH == NULL) {
422		if (errno == EEXIST)
423			errx(1, "already running as PID %d. Exiting", otherPID);
424		warn("cannot open PID file");
425	}
426}
427
428void
429ZfsDaemon::UpdatePIDFile()
430{
431	if (s_pidFH != NULL)
432		pidfile_write(s_pidFH);
433}
434
435void
436ZfsDaemon::ClosePIDFile()
437{
438	if (s_pidFH != NULL)
439		pidfile_remove(s_pidFH);
440}
441
442void
443ZfsDaemon::InitializeSyslog()
444{
445	openlog("zfsd", LOG_NDELAY, LOG_DAEMON);
446}
447
448