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 =============================*/
81 using DevdCtl::Event;
82 using DevdCtl::EventFactory;
83 using DevdCtl::EventList;
84
85 /*================================ Global Data ===============================*/
86 int g_debug = 0;
87 libzfs_handle_t *g_zfsHandle;
88
89 /*--------------------------------- ZfsDaemon --------------------------------*/
90 //- ZfsDaemon Static Private Data ----------------------------------------------
91 ZfsDaemon *ZfsDaemon::s_theZfsDaemon;
92 bool ZfsDaemon::s_logCaseFiles;
93 bool ZfsDaemon::s_terminateEventLoop;
94 char ZfsDaemon::s_pidFilePath[] = "/var/run/zfsd.pid";
95 pidfh *ZfsDaemon::s_pidFH;
96 int ZfsDaemon::s_signalPipeFD[2];
97 bool ZfsDaemon::s_systemRescanRequested(false);
98 EventFactory::Record ZfsDaemon::s_registryEntries[] =
99 {
100 { Event::NOTIFY, "GEOM", &GeomEvent::Builder },
101 { Event::NOTIFY, "ZFS", &ZfsEvent::Builder }
102 };
103
104 //- ZfsDaemon Static Public Methods --------------------------------------------
105 ZfsDaemon &
Get()106 ZfsDaemon::Get()
107 {
108 return (*s_theZfsDaemon);
109 }
110
111 void
WakeEventLoop()112 ZfsDaemon::WakeEventLoop()
113 {
114 write(s_signalPipeFD[1], "+", 1);
115 }
116
117 void
RequestSystemRescan()118 ZfsDaemon::RequestSystemRescan()
119 {
120 s_systemRescanRequested = true;
121 ZfsDaemon::WakeEventLoop();
122 }
123
124 void
Run()125 ZfsDaemon::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 --------------------------------------------------
ZfsDaemon()152 ZfsDaemon::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
~ZfsDaemon()190 ZfsDaemon::~ZfsDaemon()
191 {
192 PurgeCaseFiles();
193 ClosePIDFile();
194 }
195
196 void
PurgeCaseFiles()197 ZfsDaemon::PurgeCaseFiles()
198 {
199 CaseFile::PurgeAll();
200 }
201
202 bool
VdevAddCaseFile(Vdev & vdev,void * cbArg)203 ZfsDaemon::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
211 void
BuildCaseFiles()212 ZfsDaemon::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
258 void
RescanSystem()259 ZfsDaemon::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
301 void
DetectMissedEvents()302 ZfsDaemon::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
325 void
EventLoop()326 ZfsDaemon::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 --------------------------------------------
394 void
InfoSignalHandler(int)395 ZfsDaemon::InfoSignalHandler(int)
396 {
397 s_logCaseFiles = true;
398 ZfsDaemon::WakeEventLoop();
399 }
400
401 void
RescanSignalHandler(int)402 ZfsDaemon::RescanSignalHandler(int)
403 {
404 RequestSystemRescan();
405 }
406
407 void
QuitSignalHandler(int)408 ZfsDaemon::QuitSignalHandler(int)
409 {
410 s_terminateEventLoop = true;
411 ZfsDaemon::WakeEventLoop();
412 }
413
414 void
OpenPIDFile()415 ZfsDaemon::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
427 void
UpdatePIDFile()428 ZfsDaemon::UpdatePIDFile()
429 {
430 if (s_pidFH != NULL)
431 pidfile_write(s_pidFH);
432 }
433
434 void
ClosePIDFile()435 ZfsDaemon::ClosePIDFile()
436 {
437 if (s_pidFH != NULL)
438 pidfile_remove(s_pidFH);
439 }
440
441 void
InitializeSyslog()442 ZfsDaemon::InitializeSyslog()
443 {
444 openlog("zfsd", LOG_NDELAY, LOG_DAEMON);
445 }
446
447