+++ /dev/null
-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-#ifndef DBOBJECTMAP_DB_H
-#define DBOBJECTMAP_DB_H
-
-#include "include/buffer_fwd.h"
-#include <set>
-#include <map>
-#include <string>
-
-#include <vector>
-#include "include/memory.h"
-#include <boost/scoped_ptr.hpp>
-
-#include "os/ObjectMap.h"
-#include "kv/KeyValueDB.h"
-#include "osd/osd_types.h"
-#include "common/Mutex.h"
-#include "common/Cond.h"
-#include "common/simple_cache.hpp"
-#include <boost/optional/optional_io.hpp>
-
-#include "SequencerPosition.h"
-
-/**
- * DBObjectMap: Implements ObjectMap in terms of KeyValueDB
- *
- * Prefix space structure:
- *
- * @see complete_prefix
- * @see user_prefix
- * @see sys_prefix
- *
- * - HOBJECT_TO_SEQ: Contains leaf mapping from ghobject_t->header.seq and
- * corresponding omap header
- * - SYS_PREFIX: GLOBAL_STATE_KEY - contains next seq number
- * @see State
- * @see write_state
- * @see init
- * @see generate_new_header
- * - USER_PREFIX + header_key(header->seq) + USER_PREFIX
- * : key->value for header->seq
- * - USER_PREFIX + header_key(header->seq) + COMPLETE_PREFIX: see below
- * - USER_PREFIX + header_key(header->seq) + XATTR_PREFIX: xattrs
- * - USER_PREFIX + header_key(header->seq) + SYS_PREFIX
- * : USER_HEADER_KEY - omap header for header->seq
- * : HEADER_KEY - encoding of header for header->seq
- *
- * For each node (represented by a header), we
- * store three mappings: the key mapping, the complete mapping, and the parent.
- * The complete mapping (COMPLETE_PREFIX space) is key->key. Each x->y entry in
- * this mapping indicates that the key mapping contains all entries on [x,y).
- * Note, max string is represented by "", so ""->"" indicates that the parent
- * is unnecessary (@see rm_keys). When looking up a key not contained in the
- * the complete set, we have to check the parent if we don't find it in the
- * key set. During rm_keys, we copy keys from the parent and update the
- * complete set to reflect the change @see rm_keys.
- */
-class DBObjectMap : public ObjectMap {
-public:
- boost::scoped_ptr<KeyValueDB> db;
-
- /**
- * Serializes access to next_seq as well as the in_use set
- */
- Mutex header_lock;
- Cond header_cond;
- Cond map_header_cond;
-
- /**
- * Set of headers currently in use
- */
- set<uint64_t> in_use;
- set<ghobject_t> map_header_in_use;
-
- /**
- * Takes the map_header_in_use entry in constructor, releases in
- * destructor
- */
- class MapHeaderLock {
- DBObjectMap *db;
- boost::optional<ghobject_t> locked;
-
- MapHeaderLock(const MapHeaderLock &);
- MapHeaderLock &operator=(const MapHeaderLock &);
- public:
- explicit MapHeaderLock(DBObjectMap *db) : db(db) {}
- MapHeaderLock(DBObjectMap *db, const ghobject_t &oid) : db(db), locked(oid) {
- Mutex::Locker l(db->header_lock);
- while (db->map_header_in_use.count(*locked))
- db->map_header_cond.Wait(db->header_lock);
- db->map_header_in_use.insert(*locked);
- }
-
- const ghobject_t &get_locked() const {
- assert(locked);
- return *locked;
- }
-
- void swap(MapHeaderLock &o) {
- assert(db == o.db);
-
- // centos6's boost optional doesn't seem to have swap :(
- boost::optional<ghobject_t> _locked = o.locked;
- o.locked = locked;
- locked = _locked;
- }
-
- ~MapHeaderLock() {
- if (locked) {
- Mutex::Locker l(db->header_lock);
- assert(db->map_header_in_use.count(*locked));
- db->map_header_cond.Signal();
- db->map_header_in_use.erase(*locked);
- }
- }
- };
-
- DBObjectMap(CephContext* cct, KeyValueDB *db)
- : ObjectMap(cct), db(db), header_lock("DBOBjectMap"),
- cache_lock("DBObjectMap::CacheLock"),
- caches(cct->_conf->filestore_omap_header_cache_size)
- {}
-
- int set_keys(
- const ghobject_t &oid,
- const map<string, bufferlist> &set,
- const SequencerPosition *spos=0
- ) override;
-
- int set_header(
- const ghobject_t &oid,
- const bufferlist &bl,
- const SequencerPosition *spos=0
- ) override;
-
- int get_header(
- const ghobject_t &oid,
- bufferlist *bl
- ) override;
-
- int clear(
- const ghobject_t &oid,
- const SequencerPosition *spos=0
- ) override;
-
- int clear_keys_header(
- const ghobject_t &oid,
- const SequencerPosition *spos=0
- ) override;
-
- int rm_keys(
- const ghobject_t &oid,
- const set<string> &to_clear,
- const SequencerPosition *spos=0
- ) override;
-
- int get(
- const ghobject_t &oid,
- bufferlist *header,
- map<string, bufferlist> *out
- ) override;
-
- int get_keys(
- const ghobject_t &oid,
- set<string> *keys
- ) override;
-
- int get_values(
- const ghobject_t &oid,
- const set<string> &keys,
- map<string, bufferlist> *out
- ) override;
-
- int check_keys(
- const ghobject_t &oid,
- const set<string> &keys,
- set<string> *out
- ) override;
-
- int get_xattrs(
- const ghobject_t &oid,
- const set<string> &to_get,
- map<string, bufferlist> *out
- ) override;
-
- int get_all_xattrs(
- const ghobject_t &oid,
- set<string> *out
- ) override;
-
- int set_xattrs(
- const ghobject_t &oid,
- const map<string, bufferlist> &to_set,
- const SequencerPosition *spos=0
- ) override;
-
- int remove_xattrs(
- const ghobject_t &oid,
- const set<string> &to_remove,
- const SequencerPosition *spos=0
- ) override;
-
- int clone(
- const ghobject_t &oid,
- const ghobject_t &target,
- const SequencerPosition *spos=0
- ) override;
-
- int rename(
- const ghobject_t &from,
- const ghobject_t &to,
- const SequencerPosition *spos=0
- );
-
- int legacy_clone(
- const ghobject_t &oid,
- const ghobject_t &target,
- const SequencerPosition *spos=0
- );
-
- /// Read initial state from backing store
- int get_state();
- /// Write current state settings to DB
- void set_state();
- /// Read initial state and upgrade or initialize state
- int init(bool upgrade = false);
-
- /// Upgrade store to current version
- int upgrade_to_v2();
-
- /// Consistency check, debug, there must be no parallel writes
- int check(std::ostream &out, bool repair = false, bool force = false) override;
-
- /// Ensure that all previous operations are durable
- int sync(const ghobject_t *oid=0, const SequencerPosition *spos=0) override;
-
- void compact() override {
- assert(db);
- db->compact();
- }
-
- /// Util, get all objects, there must be no other concurrent access
- int list_objects(vector<ghobject_t> *objs ///< [out] objects
- );
-
- struct _Header;
- // Util, get all object headers, there must be no other concurrent access
- int list_object_headers(vector<_Header> *out ///< [out] headers
- );
-
- ObjectMapIterator get_iterator(const ghobject_t &oid) override;
-
- static const string USER_PREFIX;
- static const string XATTR_PREFIX;
- static const string SYS_PREFIX;
- static const string COMPLETE_PREFIX;
- static const string HEADER_KEY;
- static const string USER_HEADER_KEY;
- static const string GLOBAL_STATE_KEY;
- static const string HOBJECT_TO_SEQ;
-
- /// Legacy
- static const string LEAF_PREFIX;
- static const string REVERSE_LEAF_PREFIX;
-
- /// persistent state for store @see generate_header
- struct State {
- static const __u8 CUR_VERSION = 3;
- __u8 v;
- uint64_t seq;
- // legacy is false when complete regions never used
- bool legacy;
- State() : v(0), seq(1), legacy(false) {}
- explicit State(uint64_t seq) : v(0), seq(seq), legacy(false) {}
-
- void encode(bufferlist &bl) const {
- ENCODE_START(3, 1, bl);
- ::encode(v, bl);
- ::encode(seq, bl);
- ::encode(legacy, bl);
- ENCODE_FINISH(bl);
- }
-
- void decode(bufferlist::iterator &bl) {
- DECODE_START(3, bl);
- if (struct_v >= 2)
- ::decode(v, bl);
- else
- v = 0;
- ::decode(seq, bl);
- if (struct_v >= 3)
- ::decode(legacy, bl);
- else
- legacy = false;
- DECODE_FINISH(bl);
- }
-
- void dump(Formatter *f) const {
- f->dump_unsigned("v", v);
- f->dump_unsigned("seq", seq);
- f->dump_bool("legacy", legacy);
- }
-
- static void generate_test_instances(list<State*> &o) {
- o.push_back(new State(0));
- o.push_back(new State(20));
- }
- } state;
-
- struct _Header {
- uint64_t seq;
- uint64_t parent;
- uint64_t num_children;
-
- ghobject_t oid;
-
- SequencerPosition spos;
-
- void encode(bufferlist &bl) const {
- coll_t unused;
- ENCODE_START(2, 1, bl);
- ::encode(seq, bl);
- ::encode(parent, bl);
- ::encode(num_children, bl);
- ::encode(unused, bl);
- ::encode(oid, bl);
- ::encode(spos, bl);
- ENCODE_FINISH(bl);
- }
-
- void decode(bufferlist::iterator &bl) {
- coll_t unused;
- DECODE_START(2, bl);
- ::decode(seq, bl);
- ::decode(parent, bl);
- ::decode(num_children, bl);
- ::decode(unused, bl);
- ::decode(oid, bl);
- if (struct_v >= 2)
- ::decode(spos, bl);
- DECODE_FINISH(bl);
- }
-
- void dump(Formatter *f) const {
- f->dump_unsigned("seq", seq);
- f->dump_unsigned("parent", parent);
- f->dump_unsigned("num_children", num_children);
- f->dump_stream("oid") << oid;
- }
-
- static void generate_test_instances(list<_Header*> &o) {
- o.push_back(new _Header);
- o.push_back(new _Header);
- o.back()->parent = 20;
- o.back()->seq = 30;
- }
-
- _Header() : seq(0), parent(0), num_children(1) {}
- };
-
- /// String munging (public for testing)
- static string ghobject_key(const ghobject_t &oid);
- static string ghobject_key_v0(coll_t c, const ghobject_t &oid);
- static int is_buggy_ghobject_key_v1(CephContext* cct,
- const string &in);
-private:
- /// Implicit lock on Header->seq
- typedef ceph::shared_ptr<_Header> Header;
- Mutex cache_lock;
- SimpleLRU<ghobject_t, _Header> caches;
-
- string map_header_key(const ghobject_t &oid);
- string header_key(uint64_t seq);
- string complete_prefix(Header header);
- string user_prefix(Header header);
- string sys_prefix(Header header);
- string xattr_prefix(Header header);
- string sys_parent_prefix(_Header header);
- string sys_parent_prefix(Header header) {
- return sys_parent_prefix(*header);
- }
-
- class EmptyIteratorImpl : public ObjectMapIteratorImpl {
- public:
- int seek_to_first() override { return 0; }
- int seek_to_last() { return 0; }
- int upper_bound(const string &after) override { return 0; }
- int lower_bound(const string &to) override { return 0; }
- bool valid() override { return false; }
- int next(bool validate=true) override { ceph_abort(); return 0; }
- string key() override { ceph_abort(); return ""; }
- bufferlist value() override { ceph_abort(); return bufferlist(); }
- int status() override { return 0; }
- };
-
-
- /// Iterator
- class DBObjectMapIteratorImpl : public ObjectMapIteratorImpl {
- public:
- DBObjectMap *map;
-
- /// NOTE: implicit lock hlock->get_locked() when returned out of the class
- MapHeaderLock hlock;
- /// NOTE: implicit lock on header->seq AND for all ancestors
- Header header;
-
- /// parent_iter == NULL iff no parent
- ceph::shared_ptr<DBObjectMapIteratorImpl> parent_iter;
- KeyValueDB::Iterator key_iter;
- KeyValueDB::Iterator complete_iter;
-
- /// cur_iter points to currently valid iterator
- ceph::shared_ptr<ObjectMapIteratorImpl> cur_iter;
- int r;
-
- /// init() called, key_iter, complete_iter, parent_iter filled in
- bool ready;
- /// past end
- bool invalid;
-
- DBObjectMapIteratorImpl(DBObjectMap *map, Header header) :
- map(map), hlock(map), header(header), r(0), ready(false), invalid(true) {}
- int seek_to_first() override;
- int seek_to_last();
- int upper_bound(const string &after) override;
- int lower_bound(const string &to) override;
- bool valid() override;
- int next(bool validate=true) override;
- string key() override;
- bufferlist value() override;
- int status() override;
-
- bool on_parent() {
- return cur_iter == parent_iter;
- }
-
- /// skips to next valid parent entry
- int next_parent();
-
- /// first parent() >= to
- int lower_bound_parent(const string &to);
-
- /**
- * Tests whether to_test is in complete region
- *
- * postcondition: complete_iter will be max s.t. complete_iter->value > to_test
- */
- int in_complete_region(const string &to_test, ///< [in] key to test
- string *begin, ///< [out] beginning of region
- string *end ///< [out] end of region
- ); ///< @returns true if to_test is in the complete region, else false
-
- private:
- int init();
- bool valid_parent();
- int adjust();
- };
-
- typedef ceph::shared_ptr<DBObjectMapIteratorImpl> DBObjectMapIterator;
- DBObjectMapIterator _get_iterator(Header header) {
- return std::make_shared<DBObjectMapIteratorImpl>(this, header);
- }
-
- /// sys
-
- /// Removes node corresponding to header
- void clear_header(Header header, KeyValueDB::Transaction t);
-
- /// Set node containing input to new contents
- void set_header(Header input, KeyValueDB::Transaction t);
-
- /// Remove leaf node corresponding to oid in c
- void remove_map_header(
- const MapHeaderLock &l,
- const ghobject_t &oid,
- Header header,
- KeyValueDB::Transaction t);
-
- /// Set leaf node for c and oid to the value of header
- void set_map_header(
- const MapHeaderLock &l,
- const ghobject_t &oid, _Header header,
- KeyValueDB::Transaction t);
-
- /// Set leaf node for c and oid to the value of header
- bool check_spos(const ghobject_t &oid,
- Header header,
- const SequencerPosition *spos);
-
- /// Lookup or create header for c oid
- Header lookup_create_map_header(
- const MapHeaderLock &l,
- const ghobject_t &oid,
- KeyValueDB::Transaction t);
-
- /**
- * Generate new header for c oid with new seq number
- *
- * Has the side effect of syncronously saving the new DBObjectMap state
- */
- Header _generate_new_header(const ghobject_t &oid, Header parent);
- Header generate_new_header(const ghobject_t &oid, Header parent) {
- Mutex::Locker l(header_lock);
- return _generate_new_header(oid, parent);
- }
-
- /// Lookup leaf header for c oid
- Header _lookup_map_header(
- const MapHeaderLock &l,
- const ghobject_t &oid);
- Header lookup_map_header(
- const MapHeaderLock &l2,
- const ghobject_t &oid) {
- Mutex::Locker l(header_lock);
- return _lookup_map_header(l2, oid);
- }
-
- /// Lookup header node for input
- Header lookup_parent(Header input);
-
-
- /// Helpers
- int _get_header(Header header, bufferlist *bl);
-
- /// Scan keys in header into out_keys and out_values (if nonnull)
- int scan(Header header,
- const set<string> &in_keys,
- set<string> *out_keys,
- map<string, bufferlist> *out_values);
-
- /// Remove header and all related prefixes
- int _clear(Header header,
- KeyValueDB::Transaction t);
-
- /* Scan complete region bumping *begin to the beginning of any
- * containing region and adding all complete region keys between
- * the updated begin and end to the complete_keys_to_remove set */
- int merge_new_complete(DBObjectMapIterator &iter,
- string *begin,
- const string &end,
- set<string> *complete_keys_to_remove);
-
- /// Writes out State (mainly next_seq)
- int write_state(KeyValueDB::Transaction _t =
- KeyValueDB::Transaction());
-
- /// Copies header entry from parent @see rm_keys
- int copy_up_header(Header header,
- KeyValueDB::Transaction t);
-
- /// Sets header @see set_header
- void _set_header(Header header, const bufferlist &bl,
- KeyValueDB::Transaction t);
-
- /**
- * Removes header seq lock and possibly object lock
- * once Header is out of scope
- * @see lookup_parent
- * @see generate_new_header
- */
- class RemoveOnDelete {
- public:
- DBObjectMap *db;
- explicit RemoveOnDelete(DBObjectMap *db) :
- db(db) {}
- void operator() (_Header *header) {
- Mutex::Locker l(db->header_lock);
- assert(db->in_use.count(header->seq));
- db->in_use.erase(header->seq);
- db->header_cond.Signal();
- delete header;
- }
- };
- friend class RemoveOnDelete;
-};
-WRITE_CLASS_ENCODER(DBObjectMap::_Header)
-WRITE_CLASS_ENCODER(DBObjectMap::State)
-
-ostream& operator<<(ostream& out, const DBObjectMap::_Header& h);
-
-#endif
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