1 files changed, 282 insertions, 0 deletions
diff --git a/src/rgw/rgw_bucket_layout.h b/src/rgw/rgw_bucket_layout.h
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+++ b/src/rgw/rgw_bucket_layout.h
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+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab ft=cpp
+
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2020 Red Hat, Inc.
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation.  See file COPYING.
+ *
+ */
+
+/* N.B., this header defines fundamental serialized types.  Do not
+ * introduce changes or include files which can only be compiled in
+ * radosgw or OSD contexts (e.g., rgw_sal.h, rgw_common.h)
+ */
+
+#pragma once
+
+#include <optional>
+#include <string>
+#include "include/encoding.h"
+#include "common/ceph_json.h"
+
+namespace rgw {
+
+enum class BucketIndexType : uint8_t {
+  Normal, // normal hash-based sharded index layout
+  Indexless, // no bucket index, so listing is unsupported
+};
+
+std::string_view to_string(const BucketIndexType& t);
+bool parse(std::string_view str, BucketIndexType& t);
+void encode_json_impl(const char *name, const BucketIndexType& t, ceph::Formatter *f);
+void decode_json_obj(BucketIndexType& t, JSONObj *obj);
+
+inline std::ostream& operator<<(std::ostream& out, const BucketIndexType& t)
+{
+  return out << to_string(t);
+}
+
+enum class BucketHashType : uint8_t {
+  Mod, // rjenkins hash of object name, modulo num_shards
+};
+
+std::string_view to_string(const BucketHashType& t);
+bool parse(std::string_view str, BucketHashType& t);
+void encode_json_impl(const char *name, const BucketHashType& t, ceph::Formatter *f);
+void decode_json_obj(BucketHashType& t, JSONObj *obj);
+
+struct bucket_index_normal_layout {
+  uint32_t num_shards = 1;
+
+  BucketHashType hash_type = BucketHashType::Mod;
+
+  friend std::ostream& operator<<(std::ostream& out, const bucket_index_normal_layout& l) {
+    out << "num_shards=" << l.num_shards << ", hash_type=" << to_string(l.hash_type);
+    return out;
+  }
+};
+
+inline bool operator==(const bucket_index_normal_layout& l,
+                       const bucket_index_normal_layout& r) {
+  return l.num_shards == r.num_shards
+      && l.hash_type == r.hash_type;
+}
+inline bool operator!=(const bucket_index_normal_layout& l,
+                       const bucket_index_normal_layout& r) {
+  return !(l == r);
+}
+
+void encode(const bucket_index_normal_layout& l, bufferlist& bl, uint64_t f=0);
+void decode(bucket_index_normal_layout& l, bufferlist::const_iterator& bl);
+void encode_json_impl(const char *name, const bucket_index_normal_layout& l, ceph::Formatter *f);
+void decode_json_obj(bucket_index_normal_layout& l, JSONObj *obj);
+
+struct bucket_index_layout {
+  BucketIndexType type = BucketIndexType::Normal;
+
+  // TODO: variant of layout types?
+  bucket_index_normal_layout normal;
+
+  friend std::ostream& operator<<(std::ostream& out, const bucket_index_layout& l) {
+    out << "type=" << to_string(l.type) << ", normal=" << l.normal;
+    return out;
+  }
+};
+
+inline bool operator==(const bucket_index_layout& l,
+                       const bucket_index_layout& r) {
+  return l.type == r.type && l.normal == r.normal;
+}
+inline bool operator!=(const bucket_index_layout& l,
+                       const bucket_index_layout& r) {
+  return !(l == r);
+}
+
+void encode(const bucket_index_layout& l, bufferlist& bl, uint64_t f=0);
+void decode(bucket_index_layout& l, bufferlist::const_iterator& bl);
+void encode_json_impl(const char *name, const bucket_index_layout& l, ceph::Formatter *f);
+void decode_json_obj(bucket_index_layout& l, JSONObj *obj);
+
+struct bucket_index_layout_generation {
+  uint64_t gen = 0;
+  bucket_index_layout layout;
+
+  friend std::ostream& operator<<(std::ostream& out, const bucket_index_layout_generation& g) {
+    out << "gen=" << g.gen;
+    return out;
+  }
+};
+
+inline bool operator==(const bucket_index_layout_generation& l,
+                       const bucket_index_layout_generation& r) {
+  return l.gen == r.gen && l.layout == r.layout;
+}
+inline bool operator!=(const bucket_index_layout_generation& l,
+                       const bucket_index_layout_generation& r) {
+  return !(l == r);
+}
+
+void encode(const bucket_index_layout_generation& l, bufferlist& bl, uint64_t f=0);
+void decode(bucket_index_layout_generation& l, bufferlist::const_iterator& bl);
+void encode_json_impl(const char *name, const bucket_index_layout_generation& l, ceph::Formatter *f);
+void decode_json_obj(bucket_index_layout_generation& l, JSONObj *obj);
+
+
+enum class BucketLogType : uint8_t {
+  // colocated with bucket index, so the log layout matches the index layout
+  InIndex,
+};
+
+std::string_view to_string(const BucketLogType& t);
+bool parse(std::string_view str, BucketLogType& t);
+void encode_json_impl(const char *name, const BucketLogType& t, ceph::Formatter *f);
+void decode_json_obj(BucketLogType& t, JSONObj *obj);
+
+inline std::ostream& operator<<(std::ostream& out, const BucketLogType &log_type)
+{
+  switch (log_type) {
+    case BucketLogType::InIndex:
+      return out << "InIndex";
+    default:
+      return out << "Unknown";
+  }
+}
+
+struct bucket_index_log_layout {
+  uint64_t gen = 0;
+  bucket_index_normal_layout layout;
+  operator bucket_index_layout_generation() const {
+    bucket_index_layout_generation bilg;
+    bilg.gen = gen;
+    bilg.layout.type = BucketIndexType::Normal;
+    bilg.layout.normal = layout;
+    return bilg;
+  }
+};
+
+void encode(const bucket_index_log_layout& l, bufferlist& bl, uint64_t f=0);
+void decode(bucket_index_log_layout& l, bufferlist::const_iterator& bl);
+void encode_json_impl(const char *name, const bucket_index_log_layout& l, ceph::Formatter *f);
+void decode_json_obj(bucket_index_log_layout& l, JSONObj *obj);
+
+struct bucket_log_layout {
+  BucketLogType type = BucketLogType::InIndex;
+
+  bucket_index_log_layout in_index;
+
+  friend std::ostream& operator<<(std::ostream& out, const bucket_log_layout& l) {
+    out << "type=" << to_string(l.type);
+    return out;
+  }
+};
+
+void encode(const bucket_log_layout& l, bufferlist& bl, uint64_t f=0);
+void decode(bucket_log_layout& l, bufferlist::const_iterator& bl);
+void encode_json_impl(const char *name, const bucket_log_layout& l, ceph::Formatter *f);
+void decode_json_obj(bucket_log_layout& l, JSONObj *obj);
+
+struct bucket_log_layout_generation {
+  uint64_t gen = 0;
+  bucket_log_layout layout;
+
+  friend std::ostream& operator<<(std::ostream& out, const bucket_log_layout_generation& g) {
+    out << "gen=" << g.gen << ", layout=[ " << g.layout << " ]";
+    return out;
+  }
+};
+
+void encode(const bucket_log_layout_generation& l, bufferlist& bl, uint64_t f=0);
+void decode(bucket_log_layout_generation& l, bufferlist::const_iterator& bl);
+void encode_json_impl(const char *name, const bucket_log_layout_generation& l, ceph::Formatter *f);
+void decode_json_obj(bucket_log_layout_generation& l, JSONObj *obj);
+
+// return a log layout that shares its layout with the index
+inline bucket_log_layout_generation log_layout_from_index(
+    uint64_t gen, const bucket_index_layout_generation& index)
+{
+  return {gen, {BucketLogType::InIndex, {index.gen, index.layout.normal}}};
+}
+
+inline auto matches_gen(uint64_t gen)
+{
+  return [gen] (const bucket_log_layout_generation& l) { return l.gen == gen; };
+}
+
+inline bucket_index_layout_generation log_to_index_layout(const bucket_log_layout_generation& log_layout)
+{
+  ceph_assert(log_layout.layout.type == BucketLogType::InIndex);
+  bucket_index_layout_generation index;
+  index.gen = log_layout.layout.in_index.gen;
+  index.layout.normal = log_layout.layout.in_index.layout;
+  return index;
+}
+
+enum class BucketReshardState : uint8_t {
+  None,
+  InProgress,
+};
+std::string_view to_string(const BucketReshardState& s);
+bool parse(std::string_view str, BucketReshardState& s);
+void encode_json_impl(const char *name, const BucketReshardState& s, ceph::Formatter *f);
+void decode_json_obj(BucketReshardState& s, JSONObj *obj);
+
+// describes the layout of bucket index objects
+struct BucketLayout {
+  BucketReshardState resharding = BucketReshardState::None;
+
+  // current bucket index layout
+  bucket_index_layout_generation current_index;
+
+  // target index layout of a resharding operation
+  std::optional<bucket_index_layout_generation> target_index;
+
+  // history of untrimmed bucket log layout generations, with the current
+  // generation at the back()
+  std::vector<bucket_log_layout_generation> logs;
+
+  friend std::ostream& operator<<(std::ostream& out, const BucketLayout& l) {
+    std::stringstream ss;
+    if (l.target_index) {
+      ss << *l.target_index;
+    } else {
+      ss << "none";
+    }
+    out << "resharding=" << to_string(l.resharding) <<
+      ", current_index=[" << l.current_index << "], target_index=[" <<
+      ss.str() << "], logs.size()=" << l.logs.size();
+
+    return out;
+  }
+};
+
+void encode(const BucketLayout& l, bufferlist& bl, uint64_t f=0);
+void decode(BucketLayout& l, bufferlist::const_iterator& bl);
+void encode_json_impl(const char *name, const BucketLayout& l, ceph::Formatter *f);
+void decode_json_obj(BucketLayout& l, JSONObj *obj);
+
+
+inline uint32_t num_shards(const bucket_index_normal_layout& index) {
+  // old buckets used num_shards=0 to mean 1
+  return index.num_shards > 0 ? index.num_shards : 1;
+}
+inline uint32_t num_shards(const bucket_index_layout& index) {
+  ceph_assert(index.type == BucketIndexType::Normal);
+  return num_shards(index.normal);
+}
+inline uint32_t num_shards(const bucket_index_layout_generation& index) {
+  return num_shards(index.layout);
+}
+inline uint32_t current_num_shards(const BucketLayout& layout) {
+  return num_shards(layout.current_index);
+}
+inline bool is_layout_indexless(const bucket_index_layout_generation& layout) {
+  return layout.layout.type == BucketIndexType::Indexless;
+}
+
+} // namespace rgw