1 files changed, 111 insertions, 0 deletions
diff --git a/src/crimson/os/seastore/segment_manager/ephemeral.h b/src/crimson/os/seastore/segment_manager/ephemeral.h
new file mode 100644
index 000000000..9f19cb4d0
--- /dev/null
+++ b/src/crimson/os/seastore/segment_manager/ephemeral.h
@@ -0,0 +1,111 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#pragma once
+
+#include <boost/intrusive_ptr.hpp>
+#include <boost/smart_ptr/intrusive_ref_counter.hpp>
+#include <seastar/core/future.hh>
+
+#include "crimson/os/seastore/segment_manager.h"
+
+#include "crimson/os/seastore/segment_manager/ephemeral.h"
+
+namespace crimson::os::seastore::segment_manager {
+
+class EphemeralSegmentManager;
+using EphemeralSegmentManagerRef = std::unique_ptr<EphemeralSegmentManager>;
+
+struct ephemeral_config_t {
+  size_t size = 0;
+  size_t block_size = 0;
+  size_t segment_size = 0;
+};
+
+constexpr ephemeral_config_t DEFAULT_TEST_EPHEMERAL = {
+  1 << 30,
+  4 << 10,
+  8 << 20
+};
+
+std::ostream &operator<<(std::ostream &, const ephemeral_config_t &);
+EphemeralSegmentManagerRef create_test_ephemeral();
+
+class EphemeralSegment final : public Segment {
+  friend class EphemeralSegmentManager;
+  EphemeralSegmentManager &manager;
+  const segment_id_t id;
+  segment_off_t write_pointer = 0;
+public:
+  EphemeralSegment(EphemeralSegmentManager &manager, segment_id_t id);
+
+  segment_id_t get_segment_id() const final { return id; }
+  segment_off_t get_write_capacity() const final;
+  segment_off_t get_write_ptr() const final { return write_pointer; }
+  close_ertr::future<> close() final;
+  write_ertr::future<> write(segment_off_t offset, ceph::bufferlist bl) final;
+
+  ~EphemeralSegment() {}
+};
+
+class EphemeralSegmentManager final : public SegmentManager {
+  friend class EphemeralSegment;
+  using segment_state_t = Segment::segment_state_t;
+
+  const ephemeral_config_t config;
+  std::optional<seastore_meta_t> meta;
+
+  size_t get_offset(paddr_t addr) {
+    return (addr.segment * config.segment_size) + addr.offset;
+  }
+
+  std::vector<segment_state_t> segment_state;
+
+  char *buffer = nullptr;
+
+  Segment::close_ertr::future<> segment_close(segment_id_t id);
+
+public:
+  EphemeralSegmentManager(ephemeral_config_t config) : config(config) {}
+  ~EphemeralSegmentManager();
+
+  using init_ertr = crimson::errorator<
+    crimson::ct_error::enospc,
+    crimson::ct_error::invarg,
+    crimson::ct_error::erange>;
+  init_ertr::future<> init();
+
+  open_ertr::future<SegmentRef> open(segment_id_t id) final;
+
+  release_ertr::future<> release(segment_id_t id) final;
+
+  read_ertr::future<> read(
+    paddr_t addr,
+    size_t len,
+    ceph::bufferptr &out) final;
+
+  size_t get_size() const final {
+    return config.size;
+  }
+  segment_off_t get_block_size() const final {
+    return config.block_size;
+  }
+  segment_off_t get_segment_size() const final {
+    return config.segment_size;
+  }
+
+  const seastore_meta_t &get_meta() const final {
+    assert(meta);
+    return *meta;
+  }
+
+  void remount();
+
+  // public so tests can bypass segment interface when simpler
+  Segment::write_ertr::future<> segment_write(
+    paddr_t addr,
+    ceph::bufferlist bl,
+    bool ignore_check=false);
+};
+
+}