Propose PDisk metadata vault interface KIKIMR-19031

4 files changed, 51 insertions, 0 deletions

diff --git a/ydb/core/base/blobstorage.h b/ydb/core/base/blobstorage.h
index e0aa3e15b6b..4d3dad68997 100644
--- a/ydb/core/base/blobstorage.h
+++ b/ydb/core/base/blobstorage.h
@@ -698,6 +698,8 @@ struct TEvBlobStorage {
         EvFormatReencryptionFinish,
         EvDetectedPhantomBlobCommitted,
         EvGetLogoBlobIndexStatRequest,
+        EvReadMetadata,
+        EvWriteMetadata,
 
         EvYardInitResult = EvPut + 9 * 512,                     /// 268 636 672
         EvLogResult,
@@ -746,6 +748,8 @@ struct TEvBlobStorage {
         EvGetLogoBlobResponse,
         EvChunkForgetResult,
         EvGetLogoBlobIndexStatResponse,
+        EvReadMetadataResult,
+        EvWriteMetadataResult,
 
         // internal proxy interface
         EvUnusedLocal1 = EvPut + 10 * 512, // Not used.    /// 268 637 184
diff --git a/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h b/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h
index d78c6859d43..6064b701275 100644
--- a/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h
+++ b/ydb/core/blobstorage/pdisk/blobstorage_pdisk.h
@@ -1500,6 +1500,38 @@ struct TEvAskForCutLog : public TEventLocal<TEvAskForCutLog, TEvBlobStorage::EvA
     }
 };
 
+struct TEvReadMetadata : TEventLocal<TEvReadMetadata, TEvBlobStorage::EvReadMetadata> {};
+
+struct TEvReadMetadataResult : TEventLocal<TEvReadMetadataResult, TEvBlobStorage::EvReadMetadataResult> {
+    EPDiskMetadataOutcome Outcome;
+    TRcBuf Metadata;
+
+    TEvReadMetadataResult(EPDiskMetadataOutcome outcome)
+        : Outcome(outcome)
+    {}
+
+    TEvReadMetadataResult(TRcBuf&& metadata)
+        : Outcome(EPDiskMetadataOutcome::OK)
+        , Metadata(std::move(metadata))
+    {}
+};
+
+struct TEvWriteMetadata : TEventLocal<TEvWriteMetadata, TEvBlobStorage::EvWriteMetadata> {
+    TRcBuf Metadata;
+
+    TEvWriteMetadata(TRcBuf&& metadata)
+        : Metadata(std::move(metadata))
+    {}
+};
+
+struct TEvWriteMetadataResult : TEventLocal<TEvWriteMetadataResult, TEvBlobStorage::EvWriteMetadataResult> {
+    EPDiskMetadataOutcome Outcome;
+
+    TEvWriteMetadataResult(EPDiskMetadataOutcome outcome)
+        : Outcome(outcome)
+    {}
+};
+
 } // NPDisk
 } // NKikimr
 
diff --git a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_defs.h b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_defs.h
index 7ec5566846f..929e61c840e 100644
--- a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_defs.h
+++ b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_defs.h
@@ -33,6 +33,14 @@ namespace NKikimr {
             }
         };
 
+        enum class EPDiskMetadataOutcome {
+            OK, // metadata was successfully read/written
+            ERROR, // I/O, locking or some other kind of error has occured
+            UNFORMATTED, // pdisk is not formatted properly
+            METADATA_UNSUPPORTED, // metadata record is unsupported in this PDisk format
+            NO_METADATA, // no metadata record available
+        };
+
         typedef TPrintable_ui8 TOwner;
         typedef ui64 TOwnerRound;
         typedef ui32 TStatusFlags;
diff --git a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_tools.h b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_tools.h
index b3150e96ae5..cb8ab509075 100644
--- a/ydb/core/blobstorage/pdisk/blobstorage_pdisk_tools.h
+++ b/ydb/core/blobstorage/pdisk/blobstorage_pdisk_tools.h
@@ -49,4 +49,11 @@ void FormatPDisk(TString path, ui64 diskSizeBytes, ui32 sectorSizeBytes, ui32 us
 bool ReadPDiskFormatInfo(const TString &path, const NPDisk::TMainKey &mainKey, TPDiskInfo &outInfo,
     const bool doLock = false, TIntrusivePtr<NPDisk::TSectorMap> sectorMap = nullptr);
 
+// reads metadata from PDisk (if available)
+NPDisk::EPDiskMetadataOutcome ReadPDiskMetadata(const TString& path, const NPDisk::TKey& key, TRcBuf& metadata);
+
+// updated PDisk metadata (when PDisk is properly formatted and supports metadata vault); size of metadata should not
+// exceed 15 MiB; when function fails (even many times), previusly stored metadata must be kept intact
+NPDisk::EPDiskMetadataOutcome WritePDiskMetadata(const TString& path, const NPDisk::TKey& key, TRcBuf&& metadata);
+
 } // NKikimr