initial code repo

[stor4nfv.git] / src / ceph / src / librbd / operation / FlattenRequest.h

diff --git a/src/ceph/src/librbd/operation/FlattenRequest.h b/src/ceph/src/librbd/operation/FlattenRequest.h
new file mode 100644 (file)
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+++ b/src/ceph/src/librbd/operation/FlattenRequest.h
@@ -0,0 +1,90 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+#ifndef CEPH_LIBRBD_OPERATION_FLATTEN_REQUEST_H
+#define CEPH_LIBRBD_OPERATION_FLATTEN_REQUEST_H
+
+#include "librbd/operation/Request.h"
+#include "common/snap_types.h"
+#include "librbd/Types.h"
+
+namespace librbd {
+
+class ImageCtx;
+class ProgressContext;
+
+namespace operation {
+
+template <typename ImageCtxT = ImageCtx>
+class FlattenRequest : public Request<ImageCtxT>
+{
+public:
+  FlattenRequest(ImageCtxT &image_ctx, Context *on_finish,
+                uint64_t object_size, uint64_t overlap_objects,
+                const ::SnapContext &snapc, ProgressContext &prog_ctx)
+    : Request<ImageCtxT>(image_ctx, on_finish), m_object_size(object_size),
+      m_overlap_objects(overlap_objects), m_snapc(snapc), m_prog_ctx(prog_ctx),
+      m_ignore_enoent(false)
+  {
+  }
+
+protected:
+  void send_op() override;
+  bool should_complete(int r) override;
+
+  journal::Event create_event(uint64_t op_tid) const override {
+    return journal::FlattenEvent(op_tid);
+  }
+
+private:
+  /**
+   * Flatten goes through the following state machine to copyup objects
+   * from the parent image:
+   *
+   * @verbatim
+   *
+   * <start>
+   *    |
+   *    v
+   * STATE_FLATTEN_OBJECTS ---> STATE_UPDATE_HEADER . . . . .
+   *           .                         |                  .
+   *           .                         |                  .
+   *           .                         v                  .
+   *           .               STATE_UPDATE_CHILDREN        .
+   *           .                         |                  .
+   *           .                         |                  .
+   *           .                         \---> <finish> < . .
+   *           .                                   ^
+   *           .                                   .
+   *           . . . . . . . . . . . . . . . . . . .
+   *
+   * @endverbatim
+   *
+   * The _UPDATE_CHILDREN state will be skipped if the image has one or
+   * more snapshots. The _UPDATE_HEADER state will be skipped if the
+   * image was concurrently flattened by another client.
+   */
+  enum State {
+    STATE_FLATTEN_OBJECTS,
+    STATE_UPDATE_HEADER,
+    STATE_UPDATE_CHILDREN
+  };
+
+  uint64_t m_object_size;
+  uint64_t m_overlap_objects;
+  ::SnapContext m_snapc;
+  ProgressContext &m_prog_ctx;
+  State m_state;
+
+  ParentSpec m_parent_spec;
+  bool m_ignore_enoent;
+
+  bool send_update_header();
+  bool send_update_children();
+};
+
+} // namespace operation
+} // namespace librbd
+
+extern template class librbd::operation::FlattenRequest<librbd::ImageCtx>;
+
+#endif // CEPH_LIBRBD_OPERATION_FLATTEN_REQUEST_H