cddl/usr.sbin/zfsd/zfsd.cc

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