ceph/src/rgw/rgw_metadata.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #ifndef CEPH_RGW_METADATA_H
   5 #define CEPH_RGW_METADATA_H
   6
   7 #include <string>
   8 #include <boost/optional.hpp>
   9
  10 #include "include/types.h"
  11 #include "rgw_common.h"
  12 #include "rgw_period_history.h"
  13 #include "cls/version/cls_version_types.h"
  14 #include "cls/log/cls_log_types.h"
  15 #include "common/RWLock.h"
  16 #include "common/RefCountedObj.h"
  17 #include "common/ceph_time.h"
  18
  19
  20 class RGWRados;
  21 class RGWCoroutine;
  22 class JSONObj;
  23 struct RGWObjVersionTracker;
  24
  25 struct obj_version;
  26
  27
  28 enum RGWMDLogStatus {
  29   MDLOG_STATUS_UNKNOWN,
  30   MDLOG_STATUS_WRITE,
  31   MDLOG_STATUS_SETATTRS,
  32   MDLOG_STATUS_REMOVE,
  33   MDLOG_STATUS_COMPLETE,
  34   MDLOG_STATUS_ABORT,
  35 };
  36
  37 class RGWMetadataObject {
  38 protected:
  39   obj_version objv;
  40   ceph::real_time mtime;
  41
  42 public:
  43   RGWMetadataObject() {}
  44   virtual ~RGWMetadataObject() {}
  45   obj_version& get_version();
  46   real_time get_mtime() { return mtime; }
  47
  48   virtual void dump(Formatter *f) const = 0;
  49 };
  50
  51 class RGWMetadataManager;
  52
  53 class RGWMetadataHandler {
  54   friend class RGWMetadataManager;
  55
  56 public:
  57   enum sync_type_t {
  58     APPLY_ALWAYS,
  59     APPLY_UPDATES,
  60     APPLY_NEWER
  61   };
  62   static bool string_to_sync_type(const string& sync_string,
  63                                   sync_type_t& type) {
  64     if (sync_string.compare("update-by-version") == 0)
  65       type = APPLY_UPDATES;
  66     else if (sync_string.compare("update-by-timestamp") == 0)
  67       type = APPLY_NEWER;
  68     else if (sync_string.compare("always") == 0)
  69       type = APPLY_ALWAYS;
  70     else
  71       return false;
  72     return true;
  73   }
  74   virtual ~RGWMetadataHandler() {}
  75   virtual string get_type() = 0;
  76
  77   virtual int get(RGWRados *store, string& entry, RGWMetadataObject **obj) = 0;
  78   virtual int put(RGWRados *store, string& entry, RGWObjVersionTracker& objv_tracker,
  79                   real_time mtime, JSONObj *obj, sync_type_t type) = 0;
  80   virtual int remove(RGWRados *store, string& entry, RGWObjVersionTracker& objv_tracker) = 0;
  81
  82   virtual int list_keys_init(RGWRados *store, void **phandle) = 0;
  83   virtual int list_keys_next(void *handle, int max, list<string>& keys, bool *truncated) = 0;
  84   virtual void list_keys_complete(void *handle) = 0;
  85
  86   /* key to use for hashing entries for log shard placement */
  87   virtual void get_hash_key(const string& section, const string& key, string& hash_key) {
  88     hash_key = section + ":" + key;
  89   }
  90
  91 protected:
  92   virtual void get_pool_and_oid(RGWRados *store, const string& key, rgw_pool& pool, string& oid) = 0;
  93   /**
  94    * Compare an incoming versus on-disk tag/version+mtime combo against
  95    * the sync mode to see if the new one should replace the on-disk one.
  96    *
  97    * @return true if the update should proceed, false otherwise.
  98    */
  99   bool check_versions(const obj_version& ondisk, const real_time& ondisk_time,
 100                       const obj_version& incoming, const real_time& incoming_time,
 101                       sync_type_t sync_mode) {
 102     switch (sync_mode) {
 103     case APPLY_UPDATES:
 104       if ((ondisk.tag != incoming.tag) ||
 105           (ondisk.ver >= incoming.ver))
 106         return false;
 107       break;
 108     case APPLY_NEWER:
 109       if (ondisk_time >= incoming_time)
 110         return false;
 111       break;
 112     case APPLY_ALWAYS: //deliberate fall-thru -- we always apply!
 113     default: break;
 114     }
 115     return true;
 116   }
 117
 118   /*
 119    * The tenant_name is always returned on purpose. May be empty, of course.
 120    */
 121   static void parse_bucket(const string& bucket,
 122                            string *tenant_name,
 123                            string *bucket_name,
 124                            string *bucket_instance = nullptr /* optional */)
 125   {
 126     int pos = bucket.find('/');
 127     if (pos >= 0) {
 128       *tenant_name = bucket.substr(0, pos);
 129     } else {
 130       tenant_name->clear();
 131     }
 132     string bn = bucket.substr(pos + 1);
 133     pos = bn.find (':');
 134     if (pos < 0) {
 135       *bucket_name = std::move(bn);
 136       return;
 137     }
 138     *bucket_name = bn.substr(0, pos);
 139     if (bucket_instance) {
 140       *bucket_instance = bn.substr(pos + 1);
 141     }
 142   }
 143 };
 144
 145 #define META_LOG_OBJ_PREFIX "meta.log."
 146
 147 struct RGWMetadataLogInfo {
 148   string marker;
 149   real_time last_update;
 150
 151   void dump(Formatter *f) const;
 152   void decode_json(JSONObj *obj);
 153 };
 154
 155 class RGWCompletionManager;
 156
 157 class RGWMetadataLogInfoCompletion : public RefCountedObject {
 158  public:
 159   using info_callback_t = std::function<void(int, const cls_log_header&)>;
 160  private:
 161   cls_log_header header;
 162   librados::IoCtx io_ctx;
 163   librados::AioCompletion *completion;
 164   std::mutex mutex; //< protects callback between cancel/complete
 165   boost::optional<info_callback_t> callback; //< cleared on cancel
 166  public:
 167   RGWMetadataLogInfoCompletion(info_callback_t callback);
 168   ~RGWMetadataLogInfoCompletion() override;
 169
 170   librados::IoCtx& get_io_ctx() { return io_ctx; }
 171   cls_log_header& get_header() { return header; }
 172   librados::AioCompletion* get_completion() { return completion; }
 173
 174   void finish(librados::completion_t cb) {
 175     std::lock_guard<std::mutex> lock(mutex);
 176     if (callback) {
 177       (*callback)(completion->get_return_value(), header);
 178     }
 179   }
 180   void cancel() {
 181     std::lock_guard<std::mutex> lock(mutex);
 182     callback = boost::none;
 183   }
 184 };
 185
 186 class RGWMetadataLog {
 187   CephContext *cct;
 188   RGWRados *store;
 189   const string prefix;
 190
 191   static std::string make_prefix(const std::string& period) {
 192     if (period.empty())
 193       return META_LOG_OBJ_PREFIX;
 194     return META_LOG_OBJ_PREFIX + period + ".";
 195   }
 196
 197   RWLock lock;
 198   set<int> modified_shards;
 199
 200   void mark_modified(int shard_id);
 201 public:
 202   RGWMetadataLog(CephContext *_cct, RGWRados *_store, const std::string& period)
 203     : cct(_cct), store(_store),
 204       prefix(make_prefix(period)),
 205       lock("RGWMetaLog::lock") {}
 206
 207   void get_shard_oid(int id, string& oid) const {
 208     char buf[16];
 209     snprintf(buf, sizeof(buf), "%d", id);
 210     oid = prefix + buf;
 211   }
 212
 213   int add_entry(RGWMetadataHandler *handler, const string& section, const string& key, bufferlist& bl);
 214   int store_entries_in_shard(list<cls_log_entry>& entries, int shard_id, librados::AioCompletion *completion);
 215
 216   struct LogListCtx {
 217     int cur_shard;
 218     string marker;
 219     real_time from_time;
 220     real_time end_time;
 221
 222     string cur_oid;
 223
 224     bool done;
 225
 226     LogListCtx() : cur_shard(0), done(false) {}
 227   };
 228
 229   void init_list_entries(int shard_id, const real_time& from_time, const real_time& end_time, string& marker, void **handle);
 230   void complete_list_entries(void *handle);
 231   int list_entries(void *handle,
 232                    int max_entries,
 233                    list<cls_log_entry>& entries,
 234                    string *out_marker,
 235                    bool *truncated);
 236
 237   int trim(int shard_id, const real_time& from_time, const real_time& end_time, const string& start_marker, const string& end_marker);
 238   int get_info(int shard_id, RGWMetadataLogInfo *info);
 239   int get_info_async(int shard_id, RGWMetadataLogInfoCompletion *completion);
 240   int lock_exclusive(int shard_id, timespan duration, string&zone_id, string& owner_id);
 241   int unlock(int shard_id, string& zone_id, string& owner_id);
 242
 243   int update_shards(list<int>& shards);
 244
 245   void read_clear_modified(set<int> &modified);
 246 };
 247
 248 struct LogStatusDump {
 249   RGWMDLogStatus status;
 250
 251   explicit LogStatusDump(RGWMDLogStatus _status) : status(_status) {}
 252   void dump(Formatter *f) const;
 253 };
 254
 255 struct RGWMetadataLogData {
 256   obj_version read_version;
 257   obj_version write_version;
 258   RGWMDLogStatus status;
 259
 260   RGWMetadataLogData() : status(MDLOG_STATUS_UNKNOWN) {}
 261
 262   void encode(bufferlist& bl) const;
 263   void decode(bufferlist::iterator& bl);
 264   void dump(Formatter *f) const;
 265   void decode_json(JSONObj *obj);
 266 };
 267 WRITE_CLASS_ENCODER(RGWMetadataLogData)
 268
 269 struct RGWMetadataLogHistory {
 270   epoch_t oldest_realm_epoch;
 271   std::string oldest_period_id;
 272
 273   void encode(bufferlist& bl) const {
 274     ENCODE_START(1, 1, bl);
 275     ::encode(oldest_realm_epoch, bl);
 276     ::encode(oldest_period_id, bl);
 277     ENCODE_FINISH(bl);
 278   }
 279   void decode(bufferlist::iterator& p) {
 280     DECODE_START(1, p);
 281     ::decode(oldest_realm_epoch, p);
 282     ::decode(oldest_period_id, p);
 283     DECODE_FINISH(p);
 284   }
 285
 286   static const std::string oid;
 287 };
 288 WRITE_CLASS_ENCODER(RGWMetadataLogHistory)
 289
 290 class RGWMetadataManager {
 291   map<string, RGWMetadataHandler *> handlers;
 292   CephContext *cct;
 293   RGWRados *store;
 294
 295   // maintain a separate metadata log for each period
 296   std::map<std::string, RGWMetadataLog> md_logs;
 297   // use the current period's log for mutating operations
 298   RGWMetadataLog* current_log = nullptr;
 299
 300   void parse_metadata_key(const string& metadata_key, string& type, string& entry);
 301
 302   int find_handler(const string& metadata_key, RGWMetadataHandler **handler, string& entry);
 303   int pre_modify(RGWMetadataHandler *handler, string& section, const string& key,
 304                  RGWMetadataLogData& log_data, RGWObjVersionTracker *objv_tracker,
 305                  RGWMDLogStatus op_type);
 306   int post_modify(RGWMetadataHandler *handler, const string& section, const string& key, RGWMetadataLogData& log_data,
 307                  RGWObjVersionTracker *objv_tracker, int ret);
 308
 309   string heap_oid(RGWMetadataHandler *handler, const string& key, const obj_version& objv);
 310   int store_in_heap(RGWMetadataHandler *handler, const string& key, bufferlist& bl,
 311                     RGWObjVersionTracker *objv_tracker, real_time mtime,
 312                     map<string, bufferlist> *pattrs);
 313   int remove_from_heap(RGWMetadataHandler *handler, const string& key, RGWObjVersionTracker *objv_tracker);
 314 public:
 315   RGWMetadataManager(CephContext *_cct, RGWRados *_store);
 316   ~RGWMetadataManager();
 317
 318   int init(const std::string& current_period);
 319
 320   /// initialize the oldest log period if it doesn't exist, and attach it to
 321   /// our current history
 322   RGWPeriodHistory::Cursor init_oldest_log_period();
 323
 324   /// read the oldest log period, and return a cursor to it in our existing
 325   /// period history
 326   RGWPeriodHistory::Cursor read_oldest_log_period() const;
 327
 328   /// read the oldest log period asynchronously and write its result to the
 329   /// given cursor pointer
 330   RGWCoroutine* read_oldest_log_period_cr(RGWPeriodHistory::Cursor *period,
 331                                           RGWObjVersionTracker *objv) const;
 332
 333   /// try to advance the oldest log period when the given period is trimmed,
 334   /// using a rados lock to provide atomicity
 335   RGWCoroutine* trim_log_period_cr(RGWPeriodHistory::Cursor period,
 336                                    RGWObjVersionTracker *objv) const;
 337
 338   /// find or create the metadata log for the given period
 339   RGWMetadataLog* get_log(const std::string& period);
 340
 341   int register_handler(RGWMetadataHandler *handler);
 342
 343   RGWMetadataHandler *get_handler(const string& type);
 344
 345   int put_entry(RGWMetadataHandler *handler, const string& key, bufferlist& bl, bool exclusive,
 346                 RGWObjVersionTracker *objv_tracker, real_time mtime, map<string, bufferlist> *pattrs = NULL);
 347   int remove_entry(RGWMetadataHandler *handler, string& key, RGWObjVersionTracker *objv_tracker);
 348   int get(string& metadata_key, Formatter *f);
 349   int put(string& metadata_key, bufferlist& bl,
 350           RGWMetadataHandler::sync_type_t sync_mode,
 351           obj_version *existing_version = NULL);
 352   int remove(string& metadata_key);
 353
 354   int list_keys_init(string& section, void **phandle);
 355   int list_keys_next(void *handle, int max, list<string>& keys, bool *truncated);
 356   void list_keys_complete(void *handle);
 357
 358   void dump_log_entry(cls_log_entry& entry, Formatter *f);
 359
 360   void get_sections(list<string>& sections);
 361   int lock_exclusive(string& metadata_key, timespan duration, string& owner_id);
 362   int unlock(string& metadata_key, string& owner_id);
 363
 364   int get_log_shard_id(const string& section, const string& key, int *shard_id);
 365 };
 366
 367 #endif