src/ceph/src/osdc/WritebackHandler.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_OSDC_WRITEBACKHANDLER_H
   4 #define CEPH_OSDC_WRITEBACKHANDLER_H
   5
   6 #include "include/Context.h"
   7 #include "include/types.h"
   8 #include "osd/osd_types.h"
   9
  10 class WritebackHandler {
  11  public:
  12   WritebackHandler() {}
  13   virtual ~WritebackHandler() {}
  14
  15   virtual void read(const object_t& oid, uint64_t object_no,
  16                     const object_locator_t& oloc, uint64_t off, uint64_t len,
  17                     snapid_t snapid, bufferlist *pbl, uint64_t trunc_size,
  18                     __u32 trunc_seq, int op_flags,
  19                     const ZTracer::Trace &parent_trace, Context *onfinish) = 0;
  20   /**
  21    * check if a given extent read result may change due to a write
  22    *
  23    * Check if the content we see at the given read offset may change
  24    * due to a write to this object.
  25    *
  26    * @param oid object
  27    * @param read_off read offset
  28    * @param read_len read length
  29    * @param snapid read snapid
  30    */
  31   virtual bool may_copy_on_write(const object_t& oid, uint64_t read_off,
  32                                  uint64_t read_len, snapid_t snapid) = 0;
  33   virtual ceph_tid_t write(const object_t& oid, const object_locator_t& oloc,
  34                            uint64_t off, uint64_t len,
  35                            const SnapContext& snapc,
  36                            const bufferlist &bl, ceph::real_time mtime,
  37                            uint64_t trunc_size, __u32 trunc_seq,
  38                            ceph_tid_t journal_tid,
  39                            const ZTracer::Trace &parent_trace,
  40                            Context *oncommit) = 0;
  41
  42   virtual void overwrite_extent(const object_t& oid, uint64_t off, uint64_t len,
  43                                 ceph_tid_t original_journal_tid,
  44                                 ceph_tid_t new_journal_tid) {}
  45
  46   virtual bool can_scattered_write() { return false; }
  47   virtual ceph_tid_t write(const object_t& oid, const object_locator_t& oloc,
  48                            vector<pair<uint64_t, bufferlist> >& io_vec,
  49                            const SnapContext& snapc, ceph::real_time mtime,
  50                            uint64_t trunc_size, __u32 trunc_seq,
  51                            Context *oncommit) {
  52     return 0;
  53   }
  54 };
  55
  56 #endif