ceph/src/librbd/LibrbdWriteback.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 #ifndef CEPH_LIBRBD_LIBRBDWRITEBACKHANDLER_H
   4 #define CEPH_LIBRBD_LIBRBDWRITEBACKHANDLER_H
   5
   6 #include <queue>
   7
   8 #include "common/snap_types.h"
   9 #include "osd/osd_types.h"
  10 #include "osdc/WritebackHandler.h"
  11
  12 class Mutex;
  13 class Context;
  14
  15 namespace librbd {
  16
  17   struct ImageCtx;
  18
  19   class LibrbdWriteback : public WritebackHandler {
  20   public:
  21     LibrbdWriteback(ImageCtx *ictx, Mutex& lock);
  22
  23     // Note that oloc, trunc_size, and trunc_seq are ignored
  24     void read(const object_t& oid, uint64_t object_no,
  25               const object_locator_t& oloc, uint64_t off, uint64_t len,
  26               snapid_t snapid, bufferlist *pbl, uint64_t trunc_size,
  27               __u32 trunc_seq, int op_flags, Context *onfinish) override;
  28
  29     // Determine whether a read to this extent could be affected by a
  30     // write-triggered copy-on-write
  31     bool may_copy_on_write(const object_t& oid, uint64_t read_off,
  32                            uint64_t read_len, snapid_t snapid) override;
  33
  34     // Note that oloc, trunc_size, and trunc_seq are ignored
  35     ceph_tid_t write(const object_t& oid, const object_locator_t& oloc,
  36                      uint64_t off, uint64_t len,
  37                      const SnapContext& snapc, const bufferlist &bl,
  38                      ceph::real_time mtime, uint64_t trunc_size,
  39                      __u32 trunc_seq, ceph_tid_t journal_tid,
  40                      Context *oncommit) override;
  41     using WritebackHandler::write;
  42
  43     void overwrite_extent(const object_t& oid, uint64_t off,
  44                           uint64_t len, ceph_tid_t original_journal_tid,
  45                           ceph_tid_t new_journal_tid) override;
  46
  47     struct write_result_d {
  48       bool done;
  49       int ret;
  50       std::string oid;
  51       Context *oncommit;
  52       write_result_d(const std::string& oid, Context *oncommit) :
  53         done(false), ret(0), oid(oid), oncommit(oncommit) {}
  54     private:
  55       write_result_d(const write_result_d& rhs);
  56       const write_result_d& operator=(const write_result_d& rhs);
  57     };
  58
  59   private:
  60     void complete_writes(const std::string& oid);
  61
  62     ceph_tid_t m_tid;
  63     Mutex& m_lock;
  64     librbd::ImageCtx *m_ictx;
  65     ceph::unordered_map<std::string, std::queue<write_result_d*> > m_writes;
  66     friend class C_OrderedWrite;
  67   };
  68 }
  69
  70 #endif