1 files changed, 65 insertions, 0 deletions
diff --git a/src/crimson/os/seastore/onode_manager/simple-fltree/onode_block.h b/src/crimson/os/seastore/onode_manager/simple-fltree/onode_block.h
new file mode 100644
index 000000000..0025d9847
--- /dev/null
+++ b/src/crimson/os/seastore/onode_manager/simple-fltree/onode_block.h
@@ -0,0 +1,65 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include <cstdint>
+#include <boost/container/small_vector.hpp>
+
+#include "crimson/os/seastore/transaction_manager.h"
+#include "onode_delta.h"
+
+namespace crimson::os::seastore {
+
+// TODO s/CachedExtent/LogicalCachedExtent/
+struct OnodeBlock final : LogicalCachedExtent {
+  using Ref = TCachedExtentRef<OnodeBlock>;
+
+  template <typename... T>
+  OnodeBlock(T&&... t) : LogicalCachedExtent(std::forward<T>(t)...) {}
+  OnodeBlock(OnodeBlock&& block) = delete;
+  OnodeBlock(const OnodeBlock& block, CachedExtent::share_buffer_t tag) noexcept
+    : LogicalCachedExtent{block, tag},
+      share_buffer{true}
+  {}
+
+  CachedExtentRef duplicate_for_write() final {
+    return new OnodeBlock{*this, CachedExtent::share_buffer_t{}};
+  }
+
+  // could materialize the pending changes to the underlying buffer here,
+  // but since we write the change to the buffer immediately, let skip
+  // this for now.
+  void prepare_write() final {}
+
+  // queries
+  static constexpr extent_types_t TYPE = extent_types_t::ONODE_BLOCK;
+  extent_types_t get_type() const final {
+    return TYPE;
+  }
+
+  // have to stash all the changes before on_delta_write() is called,
+  // otherwise we could pollute the extent with pending mutations
+  // before the transaction carrying these mutations is committed to
+  // disk
+  ceph::bufferlist get_delta() final;
+  void logical_on_delta_write() final;
+  void apply_delta(const ceph::bufferlist &bl) final;
+
+  void sync() {
+    apply_pending_changes(false);
+  }
+  void mutate(delta_t&& d);
+  using mutate_func_t = std::function<void (char*, const delta_t&)>;
+  void set_delta_applier(mutate_func_t&& func) {
+    mutate_func = std::move(func);
+  }
+private:
+  // before looking at the extent, we need to make sure the content is up to date
+  void apply_pending_changes(bool do_cleanup);
+  // assuming we don't stash too many deltas to a single block
+  // otherwise a fullwrite op is necessary
+  boost::container::small_vector<std::unique_ptr<delta_t>, 2> deltas;
+  mutate_func_t mutate_func;
+  bool share_buffer = false;
+};
+
+}