ceph/src/mds/MDSMap.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15 #include "common/debug.h"
  16 #include "mon/health_check.h"
  17
  18 #include "MDSMap.h"
  19
  20 #include <sstream>
  21 using std::stringstream;
  22
  23 #define dout_context g_ceph_context
  24 #define dout_subsys ceph_subsys_
  25
  26 // features
  27 CompatSet MDSMap::get_compat_set_all() {
  28   CompatSet::FeatureSet feature_compat;
  29   CompatSet::FeatureSet feature_ro_compat;
  30   CompatSet::FeatureSet feature_incompat;
  31   feature_incompat.insert(MDS_FEATURE_INCOMPAT_BASE);
  32   feature_incompat.insert(MDS_FEATURE_INCOMPAT_CLIENTRANGES);
  33   feature_incompat.insert(MDS_FEATURE_INCOMPAT_FILELAYOUT);
  34   feature_incompat.insert(MDS_FEATURE_INCOMPAT_DIRINODE);
  35   feature_incompat.insert(MDS_FEATURE_INCOMPAT_ENCODING);
  36   feature_incompat.insert(MDS_FEATURE_INCOMPAT_OMAPDIRFRAG);
  37   feature_incompat.insert(MDS_FEATURE_INCOMPAT_INLINE);
  38   feature_incompat.insert(MDS_FEATURE_INCOMPAT_NOANCHOR);
  39   feature_incompat.insert(MDS_FEATURE_INCOMPAT_FILE_LAYOUT_V2);
  40   feature_incompat.insert(MDS_FEATURE_INCOMPAT_SNAPREALM_V2);
  41
  42   return CompatSet(feature_compat, feature_ro_compat, feature_incompat);
  43 }
  44
  45 CompatSet MDSMap::get_compat_set_default() {
  46   CompatSet::FeatureSet feature_compat;
  47   CompatSet::FeatureSet feature_ro_compat;
  48   CompatSet::FeatureSet feature_incompat;
  49   feature_incompat.insert(MDS_FEATURE_INCOMPAT_BASE);
  50   feature_incompat.insert(MDS_FEATURE_INCOMPAT_CLIENTRANGES);
  51   feature_incompat.insert(MDS_FEATURE_INCOMPAT_FILELAYOUT);
  52   feature_incompat.insert(MDS_FEATURE_INCOMPAT_DIRINODE);
  53   feature_incompat.insert(MDS_FEATURE_INCOMPAT_ENCODING);
  54   feature_incompat.insert(MDS_FEATURE_INCOMPAT_OMAPDIRFRAG);
  55   feature_incompat.insert(MDS_FEATURE_INCOMPAT_NOANCHOR);
  56   feature_incompat.insert(MDS_FEATURE_INCOMPAT_FILE_LAYOUT_V2);
  57   feature_incompat.insert(MDS_FEATURE_INCOMPAT_SNAPREALM_V2);
  58
  59   return CompatSet(feature_compat, feature_ro_compat, feature_incompat);
  60 }
  61
  62 // base (pre v0.20)
  63 CompatSet MDSMap::get_compat_set_base() {
  64   CompatSet::FeatureSet feature_compat_base;
  65   CompatSet::FeatureSet feature_incompat_base;
  66   feature_incompat_base.insert(MDS_FEATURE_INCOMPAT_BASE);
  67   CompatSet::FeatureSet feature_ro_compat_base;
  68
  69   return CompatSet(feature_compat_base, feature_ro_compat_base, feature_incompat_base);
  70 }
  71
  72 void MDSMap::mds_info_t::dump(Formatter *f) const
  73 {
  74   f->dump_unsigned("gid", global_id);
  75   f->dump_string("name", name);
  76   f->dump_int("rank", rank);
  77   f->dump_int("incarnation", inc);
  78   f->dump_stream("state") << ceph_mds_state_name(state);
  79   f->dump_int("state_seq", state_seq);
  80   f->dump_stream("addr") << addrs.get_legacy_str();
  81   f->dump_object("addrs", addrs);
  82   f->dump_int("join_fscid", join_fscid);
  83   if (laggy_since != utime_t())
  84     f->dump_stream("laggy_since") << laggy_since;
  85
  86   f->open_array_section("export_targets");
  87   for (set<mds_rank_t>::iterator p = export_targets.begin();
  88        p != export_targets.end(); ++p) {
  89     f->dump_int("mds", *p);
  90   }
  91   f->close_section();
  92   f->dump_unsigned("features", mds_features);
  93   f->dump_unsigned("flags", flags);
  94 }
  95
  96 void MDSMap::mds_info_t::dump(std::ostream& o) const
  97 {
  98   o << "[mds." << name << "{" <<  rank << ":" << global_id << "}"
  99        << " state " << ceph_mds_state_name(state)
 100        << " seq " << state_seq;
 101   if (laggy()) {
 102     o << " laggy since " << laggy_since;
 103   }
 104   if (!export_targets.empty()) {
 105     o << " export targets " << export_targets;
 106   }
 107   if (is_frozen()) {
 108     o << " frozen";
 109   }
 110   if (join_fscid != FS_CLUSTER_ID_NONE) {
 111     o << " join_fscid=" << join_fscid;
 112   }
 113   o << " addr " << addrs << "]";
 114 }
 115
 116 void MDSMap::mds_info_t::generate_test_instances(std::list<mds_info_t*>& ls)
 117 {
 118   mds_info_t *sample = new mds_info_t();
 119   ls.push_back(sample);
 120   sample = new mds_info_t();
 121   sample->global_id = 1;
 122   sample->name = "test_instance";
 123   sample->rank = 0;
 124   ls.push_back(sample);
 125 }
 126
 127 void MDSMap::dump(Formatter *f) const
 128 {
 129   f->dump_int("epoch", epoch);
 130   f->dump_unsigned("flags", flags);
 131   f->dump_unsigned("ever_allowed_features", ever_allowed_features);
 132   f->dump_unsigned("explicitly_allowed_features", explicitly_allowed_features);
 133   f->dump_stream("created") << created;
 134   f->dump_stream("modified") << modified;
 135   f->dump_int("tableserver", tableserver);
 136   f->dump_int("root", root);
 137   f->dump_int("session_timeout", session_timeout);
 138   f->dump_int("session_autoclose", session_autoclose);
 139   f->dump_stream("min_compat_client") << ceph::to_integer<int>(min_compat_client) << " ("
 140                                       << min_compat_client << ")";
 141   f->dump_int("max_file_size", max_file_size);
 142   f->dump_int("last_failure", last_failure);
 143   f->dump_int("last_failure_osd_epoch", last_failure_osd_epoch);
 144   f->open_object_section("compat");
 145   compat.dump(f);
 146   f->close_section();
 147   f->dump_int("max_mds", max_mds);
 148   f->open_array_section("in");
 149   for (set<mds_rank_t>::const_iterator p = in.begin(); p != in.end(); ++p)
 150     f->dump_int("mds", *p);
 151   f->close_section();
 152   f->open_object_section("up");
 153   for (map<mds_rank_t,mds_gid_t>::const_iterator p = up.begin(); p != up.end(); ++p) {
 154     char s[14];
 155     sprintf(s, "mds_%d", int(p->first));
 156     f->dump_int(s, p->second);
 157   }
 158   f->close_section();
 159   f->open_array_section("failed");
 160   for (set<mds_rank_t>::const_iterator p = failed.begin(); p != failed.end(); ++p)
 161     f->dump_int("mds", *p);
 162   f->close_section();
 163   f->open_array_section("damaged");
 164   for (set<mds_rank_t>::const_iterator p = damaged.begin(); p != damaged.end(); ++p)
 165     f->dump_int("mds", *p);
 166   f->close_section();
 167   f->open_array_section("stopped");
 168   for (set<mds_rank_t>::const_iterator p = stopped.begin(); p != stopped.end(); ++p)
 169     f->dump_int("mds", *p);
 170   f->close_section();
 171   f->open_object_section("info");
 172   for (const auto& [gid, info] : mds_info) {
 173     char s[25]; // 'gid_' + len(str(ULLONG_MAX)) + '\0'
 174     sprintf(s, "gid_%llu", (long long unsigned)gid);
 175     f->open_object_section(s);
 176     info.dump(f);
 177     f->close_section();
 178   }
 179   f->close_section();
 180   f->open_array_section("data_pools");
 181   for (const auto& p: data_pools)
 182     f->dump_int("pool", p);
 183   f->close_section();
 184   f->dump_int("metadata_pool", metadata_pool);
 185   f->dump_bool("enabled", enabled);
 186   f->dump_string("fs_name", fs_name);
 187   f->dump_string("balancer", balancer);
 188   f->dump_int("standby_count_wanted", std::max(0, standby_count_wanted));
 189 }
 190
 191 void MDSMap::generate_test_instances(std::list<MDSMap*>& ls)
 192 {
 193   MDSMap *m = new MDSMap();
 194   m->max_mds = 1;
 195   m->data_pools.push_back(0);
 196   m->metadata_pool = 1;
 197   m->cas_pool = 2;
 198   m->compat = get_compat_set_all();
 199
 200   // these aren't the defaults, just in case anybody gets confused
 201   m->session_timeout = 61;
 202   m->session_autoclose = 301;
 203   m->max_file_size = 1<<24;
 204   ls.push_back(m);
 205 }
 206
 207 void MDSMap::print(ostream& out) const
 208 {
 209   out << "fs_name\t" << fs_name << "\n";
 210   out << "epoch\t" << epoch << "\n";
 211   out << "flags\t" << hex << flags << dec << "\n";
 212   out << "created\t" << created << "\n";
 213   out << "modified\t" << modified << "\n";
 214   out << "tableserver\t" << tableserver << "\n";
 215   out << "root\t" << root << "\n";
 216   out << "session_timeout\t" << session_timeout << "\n"
 217       << "session_autoclose\t" << session_autoclose << "\n";
 218   out << "max_file_size\t" << max_file_size << "\n";
 219   out << "min_compat_client\t" << ceph::to_integer<int>(min_compat_client) << " ("
 220                                << min_compat_client << ")\n";
 221   out << "last_failure\t" << last_failure << "\n"
 222       << "last_failure_osd_epoch\t" << last_failure_osd_epoch << "\n";
 223   out << "compat\t" << compat << "\n";
 224   out << "max_mds\t" << max_mds << "\n";
 225   out << "in\t" << in << "\n"
 226       << "up\t" << up << "\n"
 227       << "failed\t" << failed << "\n"
 228       << "damaged\t" << damaged << "\n"
 229       << "stopped\t" << stopped << "\n";
 230   out << "data_pools\t" << data_pools << "\n";
 231   out << "metadata_pool\t" << metadata_pool << "\n";
 232   out << "inline_data\t" << (inline_data_enabled ? "enabled" : "disabled") << "\n";
 233   out << "balancer\t" << balancer << "\n";
 234   out << "standby_count_wanted\t" << std::max(0, standby_count_wanted) << "\n";
 235
 236   multimap< pair<mds_rank_t, unsigned>, mds_gid_t > foo;
 237   for (const auto &p : mds_info) {
 238     foo.insert(std::make_pair(
 239           std::make_pair(p.second.rank, p.second.inc-1), p.first));
 240   }
 241
 242   for (const auto &p : foo) {
 243     out << mds_info.at(p.second) << "\n";
 244   }
 245 }
 246
 247 void MDSMap::print_summary(Formatter *f, ostream *out) const
 248 {
 249   map<mds_rank_t,string> by_rank;
 250   map<string,int> by_state;
 251
 252   if (f) {
 253     f->dump_unsigned("epoch", get_epoch());
 254     f->dump_unsigned("up", up.size());
 255     f->dump_unsigned("in", in.size());
 256     f->dump_unsigned("max", max_mds);
 257   } else {
 258     *out << "e" << get_epoch() << ": " << up.size() << "/" << in.size() << "/" << max_mds << " up";
 259   }
 260
 261   if (f)
 262     f->open_array_section("by_rank");
 263   for (const auto &p : mds_info) {
 264     string s = ceph_mds_state_name(p.second.state);
 265     if (p.second.laggy())
 266       s += "(laggy or crashed)";
 267
 268     if (p.second.rank >= 0 && p.second.state != MDSMap::STATE_STANDBY_REPLAY) {
 269       if (f) {
 270         f->open_object_section("mds");
 271         f->dump_unsigned("rank", p.second.rank);
 272         f->dump_string("name", p.second.name);
 273         f->dump_string("status", s);
 274         f->close_section();
 275       } else {
 276         by_rank[p.second.rank] = p.second.name + "=" + s;
 277       }
 278     } else {
 279       by_state[s]++;
 280     }
 281   }
 282   if (f) {
 283     f->close_section();
 284   } else {
 285     if (!by_rank.empty())
 286       *out << " " << by_rank;
 287   }
 288
 289   for (map<string,int>::reverse_iterator p = by_state.rbegin(); p != by_state.rend(); ++p) {
 290     if (f) {
 291       f->dump_unsigned(p->first.c_str(), p->second);
 292     } else {
 293       *out << ", " << p->second << " " << p->first;
 294     }
 295   }
 296
 297   if (!failed.empty()) {
 298     if (f) {
 299       f->dump_unsigned("failed", failed.size());
 300     } else {
 301       *out << ", " << failed.size() << " failed";
 302     }
 303   }
 304
 305   if (!damaged.empty()) {
 306     if (f) {
 307       f->dump_unsigned("damaged", damaged.size());
 308     } else {
 309       *out << ", " << damaged.size() << " damaged";
 310     }
 311   }
 312   //if (stopped.size())
 313   //out << ", " << stopped.size() << " stopped";
 314 }
 315
 316 void MDSMap::get_health(list<pair<health_status_t,string> >& summary,
 317                         list<pair<health_status_t,string> > *detail) const
 318 {
 319   if (!failed.empty()) {
 320     std::ostringstream oss;
 321     oss << "mds rank"
 322         << ((failed.size() > 1) ? "s ":" ")
 323         << failed
 324         << ((failed.size() > 1) ? " have":" has")
 325         << " failed";
 326     summary.push_back(make_pair(HEALTH_ERR, oss.str()));
 327     if (detail) {
 328       for (set<mds_rank_t>::const_iterator p = failed.begin(); p != failed.end(); ++p) {
 329         std::ostringstream oss;
 330         oss << "mds." << *p << " has failed";
 331         detail->push_back(make_pair(HEALTH_ERR, oss.str()));
 332       }
 333     }
 334   }
 335
 336   if (!damaged.empty()) {
 337     std::ostringstream oss;
 338     oss << "mds rank"
 339         << ((damaged.size() > 1) ? "s ":" ")
 340         << damaged
 341         << ((damaged.size() > 1) ? " are":" is")
 342         << " damaged";
 343     summary.push_back(make_pair(HEALTH_ERR, oss.str()));
 344     if (detail) {
 345       for (set<mds_rank_t>::const_iterator p = damaged.begin(); p != damaged.end(); ++p) {
 346         std::ostringstream oss;
 347         oss << "mds." << *p << " is damaged";
 348         detail->push_back(make_pair(HEALTH_ERR, oss.str()));
 349       }
 350     }
 351   }
 352
 353   if (is_degraded()) {
 354     summary.push_back(make_pair(HEALTH_WARN, "mds cluster is degraded"));
 355     if (detail) {
 356       detail->push_back(make_pair(HEALTH_WARN, "mds cluster is degraded"));
 357       for (mds_rank_t i = mds_rank_t(0); i< get_max_mds(); i++) {
 358         if (!is_up(i))
 359           continue;
 360         mds_gid_t gid = up.find(i)->second;
 361         const auto& info = mds_info.at(gid);
 362         stringstream ss;
 363         if (is_resolve(i))
 364           ss << "mds." << info.name << " at " << info.addrs
 365              << " rank " << i << " is resolving";
 366         if (is_replay(i))
 367           ss << "mds." << info.name << " at " << info.addrs
 368              << " rank " << i << " is replaying journal";
 369         if (is_rejoin(i))
 370           ss << "mds." << info.name << " at " << info.addrs
 371              << " rank " << i << " is rejoining";
 372         if (is_reconnect(i))
 373           ss << "mds." << info.name << " at " << info.addrs
 374              << " rank " << i << " is reconnecting to clients";
 375         if (ss.str().length())
 376           detail->push_back(make_pair(HEALTH_WARN, ss.str()));
 377       }
 378     }
 379   }
 380
 381   {
 382   stringstream ss;
 383   ss << fs_name << " max_mds " << max_mds;
 384   summary.push_back(make_pair(HEALTH_WARN, ss.str()));
 385   }
 386
 387   if ((mds_rank_t)up.size() < max_mds) {
 388     stringstream ss;
 389     ss << fs_name << " has " << up.size()
 390        << " active MDS(s), but has max_mds of " << max_mds;
 391     summary.push_back(make_pair(HEALTH_WARN, ss.str()));
 392   }
 393
 394   set<string> laggy;
 395   for (const auto &u : up) {
 396     const auto& info = mds_info.at(u.second);
 397     if (info.laggy()) {
 398       laggy.insert(info.name);
 399       if (detail) {
 400         std::ostringstream oss;
 401         oss << "mds." << info.name << " at " << info.addrs
 402             << " is laggy/unresponsive";
 403         detail->push_back(make_pair(HEALTH_WARN, oss.str()));
 404       }
 405     }
 406   }
 407
 408   if (!laggy.empty()) {
 409     std::ostringstream oss;
 410     oss << "mds " << laggy
 411         << ((laggy.size() > 1) ? " are":" is")
 412         << " laggy";
 413     summary.push_back(make_pair(HEALTH_WARN, oss.str()));
 414   }
 415
 416   if (get_max_mds() > 1 &&
 417       was_snaps_ever_allowed() && !allows_multimds_snaps()) {
 418     std::ostringstream oss;
 419     oss << "multi-active mds while there are snapshots possibly created by pre-mimic MDS";
 420     summary.push_back(make_pair(HEALTH_WARN, oss.str()));
 421   }
 422 }
 423
 424 void MDSMap::get_health_checks(health_check_map_t *checks) const
 425 {
 426   // MDS_DAMAGE
 427   if (!damaged.empty()) {
 428     health_check_t& check = checks->get_or_add("MDS_DAMAGE", HEALTH_ERR,
 429                                                "%num% mds daemon%plurals% damaged",
 430                                                damaged.size());
 431     for (auto p : damaged) {
 432       std::ostringstream oss;
 433       oss << "fs " << fs_name << " mds." << p << " is damaged";
 434       check.detail.push_back(oss.str());
 435     }
 436   }
 437
 438   // FS_DEGRADED
 439   if (is_degraded()) {
 440     health_check_t& fscheck = checks->get_or_add(
 441       "FS_DEGRADED", HEALTH_WARN,
 442       "%num% filesystem%plurals% %isorare% degraded", 1);
 443     ostringstream ss;
 444     ss << "fs " << fs_name << " is degraded";
 445     fscheck.detail.push_back(ss.str());
 446
 447     list<string> detail;
 448     for (mds_rank_t i = mds_rank_t(0); i< get_max_mds(); i++) {
 449       if (!is_up(i))
 450         continue;
 451       mds_gid_t gid = up.find(i)->second;
 452       const auto& info = mds_info.at(gid);
 453       stringstream ss;
 454       ss << "fs " << fs_name << " mds." << info.name << " at "
 455          << info.addrs << " rank " << i;
 456       if (is_resolve(i))
 457         ss << " is resolving";
 458       if (is_replay(i))
 459         ss << " is replaying journal";
 460       if (is_rejoin(i))
 461         ss << " is rejoining";
 462       if (is_reconnect(i))
 463         ss << " is reconnecting to clients";
 464       if (ss.str().length())
 465         detail.push_back(ss.str());
 466     }
 467   }
 468
 469   // MDS_UP_LESS_THAN_MAX
 470   if ((mds_rank_t)get_num_in_mds() < get_max_mds()) {
 471     health_check_t& check = checks->add(
 472       "MDS_UP_LESS_THAN_MAX", HEALTH_WARN,
 473       "%num% filesystem%plurals% %isorare% online with fewer MDS than max_mds", 1);
 474     stringstream ss;
 475     ss << "fs " << fs_name << " has " << get_num_in_mds()
 476        << " MDS online, but wants " << get_max_mds();
 477     check.detail.push_back(ss.str());
 478   }
 479
 480   // MDS_ALL_DOWN
 481   if ((mds_rank_t)get_num_up_mds() == 0 && get_max_mds() > 0) {
 482     health_check_t &check = checks->add(
 483       "MDS_ALL_DOWN", HEALTH_ERR,
 484       "%num% filesystem%plurals% %isorare% offline", 1);
 485     stringstream ss;
 486     ss << "fs " << fs_name << " is offline because no MDS is active for it.";
 487     check.detail.push_back(ss.str());
 488   }
 489
 490   if (get_max_mds() > 1 &&
 491       was_snaps_ever_allowed() && !allows_multimds_snaps()) {
 492     health_check_t &check = checks->add(
 493       "MULTIMDS_WITH_OLDSNAPS", HEALTH_ERR,
 494       "%num% filesystem%plurals% %isorare% multi-active mds with old snapshots", 1);
 495     stringstream ss;
 496     ss << "multi-active mds while there are snapshots possibly created by pre-mimic MDS";
 497     check.detail.push_back(ss.str());
 498   }
 499
 500   if (get_inline_data_enabled()) {
 501     health_check_t &check = checks->add(
 502       "FS_INLINE_DATA_DEPRECATED", HEALTH_WARN,
 503       "%num% filesystem%plurals% with deprecated feature inline_data", 1);
 504     stringstream ss;
 505     ss << "fs " << fs_name << " has deprecated feature inline_data enabled.";
 506     check.detail.push_back(ss.str());
 507   }
 508 }
 509
 510 void MDSMap::mds_info_t::encode_versioned(bufferlist& bl, uint64_t features) const
 511 {
 512   __u8 v = 9;
 513   if (!HAVE_FEATURE(features, SERVER_NAUTILUS)) {
 514     v = 7;
 515   }
 516   ENCODE_START(v, 4, bl);
 517   encode(global_id, bl);
 518   encode(name, bl);
 519   encode(rank, bl);
 520   encode(inc, bl);
 521   encode((int32_t)state, bl);
 522   encode(state_seq, bl);
 523   if (v < 8) {
 524     encode(addrs.legacy_addr(), bl, features);
 525   } else {
 526     encode(addrs, bl, features);
 527   }
 528   encode(laggy_since, bl);
 529   encode(MDS_RANK_NONE, bl); /* standby_for_rank */
 530   encode(std::string(), bl); /* standby_for_name */
 531   encode(export_targets, bl);
 532   encode(mds_features, bl);
 533   encode(join_fscid, bl); /* formerly: standby_for_fscid */
 534   encode(false, bl);
 535   if (v >= 9) {
 536     encode(flags, bl);
 537   }
 538   ENCODE_FINISH(bl);
 539 }
 540
 541 void MDSMap::mds_info_t::encode_unversioned(bufferlist& bl) const
 542 {
 543   __u8 struct_v = 3;
 544   using ceph::encode;
 545   encode(struct_v, bl);
 546   encode(global_id, bl);
 547   encode(name, bl);
 548   encode(rank, bl);
 549   encode(inc, bl);
 550   encode((int32_t)state, bl);
 551   encode(state_seq, bl);
 552   encode(addrs.legacy_addr(), bl, 0);
 553   encode(laggy_since, bl);
 554   encode(MDS_RANK_NONE, bl);
 555   encode(std::string(), bl);
 556   encode(export_targets, bl);
 557 }
 558
 559 void MDSMap::mds_info_t::decode(bufferlist::const_iterator& bl)
 560 {
 561   DECODE_START_LEGACY_COMPAT_LEN(9, 4, 4, bl);
 562   decode(global_id, bl);
 563   decode(name, bl);
 564   decode(rank, bl);
 565   decode(inc, bl);
 566   decode((int32_t&)(state), bl);
 567   decode(state_seq, bl);
 568   decode(addrs, bl);
 569   decode(laggy_since, bl);
 570   {
 571     mds_rank_t standby_for_rank;
 572     decode(standby_for_rank, bl);
 573   }
 574   {
 575     std::string standby_for_name;
 576     decode(standby_for_name, bl);
 577   }
 578   if (struct_v >= 2)
 579     decode(export_targets, bl);
 580   if (struct_v >= 5)
 581     decode(mds_features, bl);
 582   if (struct_v >= 6) {
 583     decode(join_fscid, bl);
 584   }
 585   if (struct_v >= 7) {
 586     bool standby_replay;
 587     decode(standby_replay, bl);
 588   }
 589   if (struct_v >= 9) {
 590     decode(flags, bl);
 591   }
 592   DECODE_FINISH(bl);
 593 }
 594
 595 std::string MDSMap::mds_info_t::human_name() const
 596 {
 597   // Like "daemon mds.myhost restarted", "Activating daemon mds.myhost"
 598   std::ostringstream out;
 599   out << "daemon mds." << name;
 600   return out.str();
 601 }
 602
 603 void MDSMap::encode(bufferlist& bl, uint64_t features) const
 604 {
 605   std::map<mds_rank_t,int32_t> inc;  // Legacy field, fake it so that
 606                                      // old-mon peers have something sane
 607                                      // during upgrade
 608   for (const auto rank : in) {
 609     inc.insert(std::make_pair(rank, epoch));
 610   }
 611
 612   using ceph::encode;
 613   if ((features & CEPH_FEATURE_PGID64) == 0) {
 614     __u16 v = 2;
 615     encode(v, bl);
 616     encode(epoch, bl);
 617     encode(flags, bl);
 618     encode(last_failure, bl);
 619     encode(root, bl);
 620     encode(session_timeout, bl);
 621     encode(session_autoclose, bl);
 622     encode(max_file_size, bl);
 623     encode(max_mds, bl);
 624     __u32 n = mds_info.size();
 625     encode(n, bl);
 626     for (map<mds_gid_t, mds_info_t>::const_iterator i = mds_info.begin();
 627         i != mds_info.end(); ++i) {
 628       encode(i->first, bl);
 629       encode(i->second, bl, features);
 630     }
 631     n = data_pools.size();
 632     encode(n, bl);
 633     for (const auto p: data_pools) {
 634       n = p;
 635       encode(n, bl);
 636     }
 637
 638     int32_t m = cas_pool;
 639     encode(m, bl);
 640     return;
 641   } else if ((features & CEPH_FEATURE_MDSENC) == 0) {
 642     __u16 v = 3;
 643     encode(v, bl);
 644     encode(epoch, bl);
 645     encode(flags, bl);
 646     encode(last_failure, bl);
 647     encode(root, bl);
 648     encode(session_timeout, bl);
 649     encode(session_autoclose, bl);
 650     encode(max_file_size, bl);
 651     encode(max_mds, bl);
 652     __u32 n = mds_info.size();
 653     encode(n, bl);
 654     for (map<mds_gid_t, mds_info_t>::const_iterator i = mds_info.begin();
 655         i != mds_info.end(); ++i) {
 656       encode(i->first, bl);
 657       encode(i->second, bl, features);
 658     }
 659     encode(data_pools, bl);
 660     encode(cas_pool, bl);
 661
 662     __u16 ev = 5;
 663     encode(ev, bl);
 664     encode(compat, bl);
 665     encode(metadata_pool, bl);
 666     encode(created, bl);
 667     encode(modified, bl);
 668     encode(tableserver, bl);
 669     encode(in, bl);
 670     encode(inc, bl);
 671     encode(up, bl);
 672     encode(failed, bl);
 673     encode(stopped, bl);
 674     encode(last_failure_osd_epoch, bl);
 675     return;
 676   }
 677
 678   ENCODE_START(5, 4, bl);
 679   encode(epoch, bl);
 680   encode(flags, bl);
 681   encode(last_failure, bl);
 682   encode(root, bl);
 683   encode(session_timeout, bl);
 684   encode(session_autoclose, bl);
 685   encode(max_file_size, bl);
 686   encode(max_mds, bl);
 687   encode(mds_info, bl, features);
 688   encode(data_pools, bl);
 689   encode(cas_pool, bl);
 690
 691   __u16 ev = 15;
 692   encode(ev, bl);
 693   encode(compat, bl);
 694   encode(metadata_pool, bl);
 695   encode(created, bl);
 696   encode(modified, bl);
 697   encode(tableserver, bl);
 698   encode(in, bl);
 699   encode(inc, bl);
 700   encode(up, bl);
 701   encode(failed, bl);
 702   encode(stopped, bl);
 703   encode(last_failure_osd_epoch, bl);
 704   encode(ever_allowed_features, bl);
 705   encode(explicitly_allowed_features, bl);
 706   encode(inline_data_enabled, bl);
 707   encode(enabled, bl);
 708   encode(fs_name, bl);
 709   encode(damaged, bl);
 710   encode(balancer, bl);
 711   encode(standby_count_wanted, bl);
 712   encode(old_max_mds, bl);
 713   encode(min_compat_client, bl);
 714   ENCODE_FINISH(bl);
 715 }
 716
 717 void MDSMap::sanitize(const std::function<bool(int64_t pool)>& pool_exists)
 718 {
 719   /* Before we did stricter checking, it was possible to remove a data pool
 720    * without also deleting it from the MDSMap. Check for that here after
 721    * decoding the data pools.
 722    */
 723
 724   for (auto it = data_pools.begin(); it != data_pools.end();) {
 725     if (!pool_exists(*it)) {
 726       dout(0) << "removed non-existant data pool " << *it << " from MDSMap" << dendl;
 727       it = data_pools.erase(it);
 728     } else {
 729       it++;
 730     }
 731   }
 732 }
 733
 734 void MDSMap::decode(bufferlist::const_iterator& p)
 735 {
 736   std::map<mds_rank_t,int32_t> inc;  // Legacy field, parse and drop
 737
 738   cached_up_features = 0;
 739   DECODE_START_LEGACY_COMPAT_LEN_16(5, 4, 4, p);
 740   decode(epoch, p);
 741   decode(flags, p);
 742   decode(last_failure, p);
 743   decode(root, p);
 744   decode(session_timeout, p);
 745   decode(session_autoclose, p);
 746   decode(max_file_size, p);
 747   decode(max_mds, p);
 748   decode(mds_info, p);
 749   if (struct_v < 3) {
 750     __u32 n;
 751     decode(n, p);
 752     while (n--) {
 753       __u32 m;
 754       decode(m, p);
 755       data_pools.push_back(m);
 756     }
 757     __s32 s;
 758     decode(s, p);
 759     cas_pool = s;
 760   } else {
 761     decode(data_pools, p);
 762     decode(cas_pool, p);
 763   }
 764
 765   // kclient ignores everything from here
 766   __u16 ev = 1;
 767   if (struct_v >= 2)
 768     decode(ev, p);
 769   if (ev >= 3)
 770     decode(compat, p);
 771   else
 772     compat = get_compat_set_base();
 773   if (ev < 5) {
 774     __u32 n;
 775     decode(n, p);
 776     metadata_pool = n;
 777   } else {
 778     decode(metadata_pool, p);
 779   }
 780   decode(created, p);
 781   decode(modified, p);
 782   decode(tableserver, p);
 783   decode(in, p);
 784   decode(inc, p);
 785   decode(up, p);
 786   decode(failed, p);
 787   decode(stopped, p);
 788   if (ev >= 4)
 789     decode(last_failure_osd_epoch, p);
 790   if (ev >= 6) {
 791     if (ev < 10) {
 792       // previously this was a bool about snaps, not a flag map
 793       bool flag;
 794       decode(flag, p);
 795       ever_allowed_features = flag ? CEPH_MDSMAP_ALLOW_SNAPS : 0;
 796       decode(flag, p);
 797       explicitly_allowed_features = flag ? CEPH_MDSMAP_ALLOW_SNAPS : 0;
 798     } else {
 799       decode(ever_allowed_features, p);
 800       decode(explicitly_allowed_features, p);
 801     }
 802   } else {
 803     ever_allowed_features = 0;
 804     explicitly_allowed_features = 0;
 805   }
 806   if (ev >= 7)
 807     decode(inline_data_enabled, p);
 808
 809   if (ev >= 8) {
 810     ceph_assert(struct_v >= 5);
 811     decode(enabled, p);
 812     decode(fs_name, p);
 813   } else {
 814     if (epoch > 1) {
 815       // If an MDS has ever been started, epoch will be greater than 1,
 816       // assume filesystem is enabled.
 817       enabled = true;
 818     } else {
 819       // Upgrading from a cluster that never used an MDS, switch off
 820       // filesystem until it's explicitly enabled.
 821       enabled = false;
 822     }
 823   }
 824
 825   if (ev >= 9) {
 826     decode(damaged, p);
 827   }
 828
 829   if (ev >= 11) {
 830     decode(balancer, p);
 831   }
 832
 833   if (ev >= 12) {
 834     decode(standby_count_wanted, p);
 835   }
 836
 837   if (ev >= 13) {
 838     decode(old_max_mds, p);
 839   }
 840
 841   if (ev == 14) {
 842     int8_t r;
 843     decode(r, p);
 844     if (r < 0) {
 845       min_compat_client = ceph_release_t::unknown;
 846     } else {
 847       min_compat_client = ceph_release_t{static_cast<uint8_t>(r)};
 848     }
 849   } else if (ev > 14) {
 850     decode(min_compat_client, p);
 851   }
 852
 853   DECODE_FINISH(p);
 854 }
 855
 856 MDSMap::availability_t MDSMap::is_cluster_available() const
 857 {
 858   if (epoch == 0) {
 859     // If I'm a client, this means I'm looking at an MDSMap instance
 860     // that was never actually initialized from the mons.  Client should
 861     // wait.
 862     return TRANSIENT_UNAVAILABLE;
 863   }
 864
 865   // If a rank is marked damage (unavailable until operator intervenes)
 866   if (damaged.size()) {
 867     return STUCK_UNAVAILABLE;
 868   }
 869
 870   // If no ranks are created (filesystem not initialized)
 871   if (in.empty()) {
 872     return STUCK_UNAVAILABLE;
 873   }
 874
 875   for (const auto rank : in) {
 876     if (up.count(rank) && mds_info.at(up.at(rank)).laggy()) {
 877       // This might only be transient, but because we can't see
 878       // standbys, we have no way of knowing whether there is a
 879       // standby available to replace the laggy guy.
 880       return STUCK_UNAVAILABLE;
 881     }
 882   }
 883
 884   if (get_num_mds(CEPH_MDS_STATE_ACTIVE) > 0) {
 885     // Nobody looks stuck, so indicate to client they should go ahead
 886     // and try mounting if anybody is active.  This may include e.g.
 887     // one MDS failing over and another active: the client should
 888     // proceed to start talking to the active one and let the
 889     // transiently-unavailable guy catch up later.
 890     return AVAILABLE;
 891   } else {
 892     // Nothing indicating we were stuck, but nobody active (yet)
 893     //return TRANSIENT_UNAVAILABLE;
 894
 895     // Because we don't have standbys in the MDSMap any more, we can't
 896     // reliably indicate transient vs. stuck, so always say stuck so
 897     // that the client doesn't block.
 898     return STUCK_UNAVAILABLE;
 899   }
 900 }
 901
 902 bool MDSMap::state_transition_valid(DaemonState prev, DaemonState next)
 903 {
 904   bool state_valid = true;
 905   if (next != prev) {
 906     if (prev == MDSMap::STATE_REPLAY) {
 907       if (next != MDSMap::STATE_RESOLVE && next != MDSMap::STATE_RECONNECT) {
 908         state_valid = false;
 909       }
 910     } else if (prev == MDSMap::STATE_REJOIN) {
 911       if (next != MDSMap::STATE_ACTIVE &&
 912           next != MDSMap::STATE_CLIENTREPLAY &&
 913           next != MDSMap::STATE_STOPPED) {
 914         state_valid = false;
 915       }
 916     } else if (prev >= MDSMap::STATE_RESOLVE && prev < MDSMap::STATE_ACTIVE) {
 917       // Once I have entered replay, the only allowable transitions are to
 918       // the next next along in the sequence.
 919       if (next != prev + 1) {
 920         state_valid = false;
 921       }
 922     }
 923   }
 924
 925   return state_valid;
 926 }
 927
 928 bool MDSMap::check_health(mds_rank_t standby_daemon_count)
 929 {
 930   std::set<mds_rank_t> standbys;
 931   get_standby_replay_mds_set(standbys);
 932   std::set<mds_rank_t> actives;
 933   get_active_mds_set(actives);
 934   mds_rank_t standbys_avail = (mds_rank_t)standbys.size()+standby_daemon_count;
 935
 936   /* If there are standby daemons available/replaying and
 937    * standby_count_wanted is unset (default), then we set it to 1. This will
 938    * happen during health checks by the mons. Also, during initial creation
 939    * of the FS we will have no actives so we don't want to change the default
 940    * yet.
 941    */
 942   if (standby_count_wanted == -1 && actives.size() > 0 && standbys_avail > 0) {
 943     set_standby_count_wanted(1);
 944     return true;
 945   }
 946   return false;
 947 }
 948
 949 mds_gid_t MDSMap::find_mds_gid_by_name(std::string_view s) const {
 950   for (const auto& [gid, info] : mds_info) {
 951     if (info.name == s) {
 952       return gid;
 953     }
 954   }
 955   return MDS_GID_NONE;
 956 }
 957
 958 unsigned MDSMap::get_num_mds(int state) const {
 959   unsigned n = 0;
 960   for (std::map<mds_gid_t,mds_info_t>::const_iterator p = mds_info.begin();
 961        p != mds_info.end();
 962        ++p)
 963     if (p->second.state == state) ++n;
 964   return n;
 965 }
 966
 967 void MDSMap::get_up_mds_set(std::set<mds_rank_t>& s) const {
 968   for (std::map<mds_rank_t, mds_gid_t>::const_iterator p = up.begin();
 969        p != up.end();
 970        ++p)
 971     s.insert(p->first);
 972 }
 973
 974 uint64_t MDSMap::get_up_features() {
 975   if (!cached_up_features) {
 976     bool first = true;
 977     for (std::map<mds_rank_t, mds_gid_t>::const_iterator p = up.begin();
 978          p != up.end();
 979          ++p) {
 980       std::map<mds_gid_t, mds_info_t>::const_iterator q =
 981         mds_info.find(p->second);
 982       ceph_assert(q != mds_info.end());
 983       if (first) {
 984         cached_up_features = q->second.mds_features;
 985         first = false;
 986       } else {
 987         cached_up_features &= q->second.mds_features;
 988       }
 989     }
 990   }
 991   return cached_up_features;
 992 }
 993
 994 void MDSMap::get_recovery_mds_set(std::set<mds_rank_t>& s) const {
 995   s = failed;
 996   for (const auto& p : damaged)
 997     s.insert(p);
 998   for (const auto& p : mds_info)
 999     if (p.second.state >= STATE_REPLAY && p.second.state <= STATE_STOPPING)
1000       s.insert(p.second.rank);
1001 }
1002
1003 void MDSMap::get_mds_set_lower_bound(std::set<mds_rank_t>& s, DaemonState first) const {
1004   for (std::map<mds_gid_t, mds_info_t>::const_iterator p = mds_info.begin();
1005        p != mds_info.end();
1006        ++p)
1007     if (p->second.state >= first && p->second.state <= STATE_STOPPING)
1008       s.insert(p->second.rank);
1009 }
1010
1011 void MDSMap::get_mds_set(std::set<mds_rank_t>& s, DaemonState state) const {
1012   for (std::map<mds_gid_t, mds_info_t>::const_iterator p = mds_info.begin();
1013        p != mds_info.end();
1014        ++p)
1015     if (p->second.state == state)
1016       s.insert(p->second.rank);
1017 }
1018
1019 mds_gid_t MDSMap::get_standby_replay(mds_rank_t r) const {
1020   for (auto& [gid,info] : mds_info) {
1021     if (info.rank == r && info.state == STATE_STANDBY_REPLAY) {
1022       return gid;
1023     }
1024   }
1025   return MDS_GID_NONE;
1026 }
1027
1028 bool MDSMap::is_degraded() const {
1029   if (!failed.empty() || !damaged.empty())
1030     return true;
1031   for (const auto& p : mds_info) {
1032     if (p.second.is_degraded())
1033       return true;
1034   }
1035   return false;
1036 }