1 files changed, 156 insertions, 0 deletions
diff --git a/src/librbd/operation/ResizeRequest.h b/src/librbd/operation/ResizeRequest.h
new file mode 100644
index 000000000..f5e2f807f
--- /dev/null
+++ b/src/librbd/operation/ResizeRequest.h
@@ -0,0 +1,156 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+#ifndef CEPH_LIBRBD_OPERATION_RESIZE_REQUEST_H
+#define CEPH_LIBRBD_OPERATION_RESIZE_REQUEST_H
+
+#include "librbd/operation/Request.h"
+#include "include/xlist.h"
+
+namespace librbd
+{
+
+class ImageCtx;
+class ProgressContext;
+
+namespace operation {
+
+template <typename ImageCtxT = ImageCtx>
+class ResizeRequest : public Request<ImageCtxT> {
+public:
+  static ResizeRequest *create(ImageCtxT &image_ctx, Context *on_finish,
+                               uint64_t new_size, bool allow_shrink,
+                               ProgressContext &prog_ctx, uint64_t journal_op_tid,
+                               bool disable_journal) {
+    return new ResizeRequest(image_ctx, on_finish, new_size, allow_shrink, prog_ctx,
+                             journal_op_tid, disable_journal);
+  }
+
+  ResizeRequest(ImageCtxT &image_ctx, Context *on_finish, uint64_t new_size,
+                bool allow_shrink, ProgressContext &prog_ctx, uint64_t journal_op_tid,
+                bool disable_journal);
+  ~ResizeRequest() override;
+
+  inline bool shrinking() const {
+    return (m_shrink_size_visible && m_new_size < m_original_size);
+  }
+
+  inline uint64_t get_image_size() const {
+    return m_new_size;
+  }
+
+  void send() override;
+
+protected:
+  void send_op() override;
+  bool should_complete(int r) override {
+    return true;
+  }
+  bool can_affect_io() const override {
+    return true;
+  }
+  journal::Event create_event(uint64_t op_tid) const override {
+    return journal::ResizeEvent(op_tid, m_new_size);
+  }
+
+private:
+  /**
+   * Resize goes through the following state machine to resize the image
+   * and update the object map:
+   *
+   * @verbatim
+   *
+   * <start>
+   *    |
+   *    v
+   * STATE_PRE_BLOCK_WRITES
+   *    |
+   *    v
+   * STATE_APPEND_OP_EVENT (skip if journaling
+   *    |                   disabled)
+   *    |
+   *    | (grow)
+   *    |\--------> STATE_GROW_OBJECT_MAP (skip if object map
+   *    |                 |                disabled)
+   *    |                 v
+   *    |           STATE_UPDATE_HEADER ----------------------------\
+   *    |                                 (unblock writes)          |
+   *    |                                                           |
+   *    | (unblock writes)                                          |
+   *    |                                                           |
+   *    | (shrink)                                                  |
+   *    |\--------> STATE_FLUSH_CACHE                               |
+   *    |                 |                                         |
+   *    |                 v                                         |
+   *    |           STATE_INVALIDATE_CACHE                          |
+   *    |                 |                                         |
+   *    |                 v                                         |
+   *    |           STATE_TRIM_IMAGE                                |
+   *    |                 |                                         |
+   *    |                 v                                         |
+   *    |           STATE_POST_BLOCK_WRITES                         |
+   *    |                 |                                         |
+   *    |                 v                                         |
+   *    |           STATE_UPDATE_HEADER                             |
+   *    |                 |                                         |
+   *    |                 v                                         |
+   *    |           STATE_SHRINK_OBJECT_MAP (skip if object map     |
+   *    |                 |                  disabled)              |
+   *    |                 | (unblock writes)                        |
+   *    | (no change)     v                                         |
+   *    \------------> <finish> <-----------------------------------/
+   *
+   * @endverbatim
+   *
+   * The _OBJECT_MAP states are skipped if the object map isn't enabled.
+   * The state machine will immediately transition to _FINISHED if there
+   * are no objects to trim.
+   */
+
+  uint64_t m_original_size;
+  uint64_t m_new_size;
+  bool m_allow_shrink = true;
+  ProgressContext &m_prog_ctx;
+  uint64_t m_new_parent_overlap;
+  bool m_shrink_size_visible = false;
+  bool m_disable_journal = false;
+
+  typename xlist<ResizeRequest<ImageCtxT>*>::item m_xlist_item;
+
+  void send_pre_block_writes();
+  Context *handle_pre_block_writes(int *result);
+
+  Context *send_append_op_event();
+  Context *handle_append_op_event(int *result);
+
+  void send_flush_cache();
+  Context *handle_flush_cache(int *result);
+
+  void send_invalidate_cache();
+  Context *handle_invalidate_cache(int *result);
+
+  void send_trim_image();
+  Context *handle_trim_image(int *result);
+
+  Context *send_grow_object_map();
+  Context *handle_grow_object_map(int *result);
+
+  Context *send_shrink_object_map();
+  Context *handle_shrink_object_map(int *result);
+
+  void send_post_block_writes();
+  Context *handle_post_block_writes(int *result);
+
+  void send_update_header();
+  Context *handle_update_header(int *result);
+
+  void compute_parent_overlap();
+  void update_size_and_overlap();
+
+};
+
+} // namespace operation
+} // namespace librbd
+
+extern template class librbd::operation::ResizeRequest<librbd::ImageCtx>;
+
+#endif // CEPH_LIBRBD_OPERATION_RESIZE_REQUEST_H