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