ceph/src/mds/snap.h

   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 #ifndef CEPH_MDS_SNAP_H
  16 #define CEPH_MDS_SNAP_H
  17
  18 #include <string_view>
  19
  20 #include "mdstypes.h"
  21 #include "common/snap_types.h"
  22
  23 #include "Capability.h"
  24
  25 /*
  26  * generic snap descriptor.
  27  */
  28 struct SnapInfo {
  29   void encode(bufferlist &bl) const;
  30   void decode(bufferlist::const_iterator &bl);
  31   void dump(Formatter *f) const;
  32   static void generate_test_instances(std::list<SnapInfo*>& ls);
  33
  34   std::string_view get_long_name() const;
  35
  36   snapid_t snapid;
  37   inodeno_t ino;
  38   utime_t stamp;
  39   string name;
  40
  41   mutable string long_name; ///< cached _$ino_$name
  42 };
  43 WRITE_CLASS_ENCODER(SnapInfo)
  44
  45 inline bool operator==(const SnapInfo &l, const SnapInfo &r)
  46 {
  47   return l.snapid == r.snapid && l.ino == r.ino &&
  48          l.stamp == r.stamp && l.name == r.name;
  49 }
  50
  51 ostream& operator<<(ostream& out, const SnapInfo &sn);
  52
  53 /*
  54  * SnapRealm - a subtree that shares the same set of snapshots.
  55  */
  56 struct SnapRealm;
  57
  58 struct snaplink_t {
  59   void encode(bufferlist &bl) const;
  60   void decode(bufferlist::const_iterator &bl);
  61   void dump(Formatter *f) const;
  62   static void generate_test_instances(std::list<snaplink_t*>& ls);
  63
  64   inodeno_t ino;
  65   snapid_t first;
  66 };
  67 WRITE_CLASS_ENCODER(snaplink_t)
  68
  69 ostream& operator<<(ostream& out, const snaplink_t &l);
  70
  71 // carry data about a specific version of a SnapRealm
  72 struct sr_t {
  73   void mark_parent_global() { flags |= PARENT_GLOBAL; }
  74   void clear_parent_global() { flags &= ~PARENT_GLOBAL; }
  75   bool is_parent_global() const { return flags & PARENT_GLOBAL; }
  76
  77   void encode(bufferlist &bl) const;
  78   void decode(bufferlist::const_iterator &bl);
  79   void dump(Formatter *f) const;
  80   static void generate_test_instances(std::list<sr_t*>& ls);
  81
  82   snapid_t seq = 0;                     // basically, a version/seq # for changes to _this_ realm.
  83   snapid_t created = 0;                 // when this realm was created.
  84   snapid_t last_created = 0;            // last snap created in _this_ realm.
  85   snapid_t last_destroyed = 0;          // seq for last removal
  86   snapid_t current_parent_since = 1;
  87   map<snapid_t, SnapInfo> snaps;
  88   map<snapid_t, snaplink_t> past_parents;  // key is "last" (or NOSNAP)
  89   set<snapid_t> past_parent_snaps;
  90
  91   __u32 flags = 0;
  92   enum {
  93     PARENT_GLOBAL = 1 << 0,
  94   };
  95 };
  96 WRITE_CLASS_ENCODER(sr_t)
  97
  98 class MDCache;
  99 #endif