1 files changed, 72 insertions, 0 deletions
diff --git a/src/librbd/LibrbdWriteback.h b/src/librbd/LibrbdWriteback.h
new file mode 100644
index 00000000..6ffba511
--- /dev/null
+++ b/src/librbd/LibrbdWriteback.h
@@ -0,0 +1,72 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+#ifndef CEPH_LIBRBD_LIBRBDWRITEBACKHANDLER_H
+#define CEPH_LIBRBD_LIBRBDWRITEBACKHANDLER_H
+
+#include <queue>
+
+#include "common/snap_types.h"
+#include "osd/osd_types.h"
+#include "osdc/WritebackHandler.h"
+
+class Mutex;
+class Context;
+
+namespace librbd {
+
+  struct ImageCtx;
+
+  class LibrbdWriteback : public WritebackHandler {
+  public:
+    LibrbdWriteback(ImageCtx *ictx, Mutex& lock);
+
+    // Note that oloc, trunc_size, and trunc_seq are ignored
+    void read(const object_t& oid, uint64_t object_no,
+              const object_locator_t& oloc, uint64_t off, uint64_t len,
+              snapid_t snapid, bufferlist *pbl, uint64_t trunc_size,
+              __u32 trunc_seq, int op_flags,
+	      const ZTracer::Trace &parent_trace, Context *onfinish) override;
+
+    // Determine whether a read to this extent could be affected by a
+    // write-triggered copy-on-write
+    bool may_copy_on_write(const object_t& oid, uint64_t read_off,
+                           uint64_t read_len, snapid_t snapid) override;
+
+    // Note that oloc, trunc_size, and trunc_seq are ignored
+    ceph_tid_t write(const object_t& oid, const object_locator_t& oloc,
+                     uint64_t off, uint64_t len,
+                     const SnapContext& snapc, const bufferlist &bl,
+                     ceph::real_time mtime, uint64_t trunc_size,
+                     __u32 trunc_seq, ceph_tid_t journal_tid,
+                     const ZTracer::Trace &parent_trace,
+                     Context *oncommit) override;
+    using WritebackHandler::write;
+
+    void overwrite_extent(const object_t& oid, uint64_t off,
+                          uint64_t len, ceph_tid_t original_journal_tid,
+                          ceph_tid_t new_journal_tid) override;
+
+    struct write_result_d {
+      bool done;
+      int ret;
+      std::string oid;
+      Context *oncommit;
+      write_result_d(const std::string& oid, Context *oncommit) :
+        done(false), ret(0), oid(oid), oncommit(oncommit) {}
+    private:
+      write_result_d(const write_result_d& rhs);
+      const write_result_d& operator=(const write_result_d& rhs);
+    };
+
+  private:
+    void complete_writes(const std::string& oid);
+
+    ceph_tid_t m_tid;
+    Mutex& m_lock;
+    librbd::ImageCtx *m_ictx;
+    ceph::unordered_map<std::string, std::queue<write_result_d*> > m_writes;
+    friend class C_OrderedWrite;
+  };
+}
+
+#endif