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, "GEOM",  &GeomEvent::Builder },
 102         { Event::NOTIFY, "ZFS",   &ZfsEvent::Builder }
 103 };
 104
 105 //- ZfsDaemon Static Public Methods --------------------------------------------
 106 ZfsDaemon &
 107 ZfsDaemon::Get()
 108 {
 109         return (*s_theZfsDaemon);
 110 }
 111
 112 void
 113 ZfsDaemon::WakeEventLoop()
 114 {
 115         write(s_signalPipeFD[1], "+", 1);
 116 }
 117
 118 void
 119 ZfsDaemon::RequestSystemRescan()
 120 {
 121         s_systemRescanRequested = true;
 122         ZfsDaemon::WakeEventLoop();
 123 }
 124
 125 void
 126 ZfsDaemon::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 --------------------------------------------------
 153 ZfsDaemon::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
 191 ZfsDaemon::~ZfsDaemon()
 192 {
 193         PurgeCaseFiles();
 194         ClosePIDFile();
 195 }
 196
 197 void
 198 ZfsDaemon::PurgeCaseFiles()
 199 {
 200         CaseFile::PurgeAll();
 201 }
 202
 203 bool
 204 ZfsDaemon::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
 212 void
 213 ZfsDaemon::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
 259 void
 260 ZfsDaemon::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
 302 void
 303 ZfsDaemon::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
 326 void
 327 ZfsDaemon::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 --------------------------------------------
 395 void
 396 ZfsDaemon::InfoSignalHandler(int)
 397 {
 398         s_logCaseFiles = true;
 399         ZfsDaemon::WakeEventLoop();
 400 }
 401
 402 void
 403 ZfsDaemon::RescanSignalHandler(int)
 404 {
 405         RequestSystemRescan();
 406 }
 407
 408 void
 409 ZfsDaemon::QuitSignalHandler(int)
 410 {
 411         s_terminateEventLoop = true;
 412         ZfsDaemon::WakeEventLoop();
 413 }
 414
 415 void
 416 ZfsDaemon::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
 428 void
 429 ZfsDaemon::UpdatePIDFile()
 430 {
 431         if (s_pidFH != NULL)
 432                 pidfile_write(s_pidFH);
 433 }
 434
 435 void
 436 ZfsDaemon::ClosePIDFile()
 437 {
 438         if (s_pidFH != NULL)
 439                 pidfile_remove(s_pidFH);
 440 }
 441
 442 void
 443 ZfsDaemon::InitializeSyslog()
 444 {
 445         openlog("zfsd", LOG_NDELAY, LOG_DAEMON);
 446 }
 447