Module fxfs::object_store

Re-exports

• pub use caching_object_handle::CachingObjectHandle;
• pub use directory::Directory;
• pub use allocator::AllocatorInfo;
• pub use allocator::AllocatorKey;
• pub use allocator::AllocatorValue;
• pub use journal::JournalRecord;
• pub use journal::JournalRecordV20;
• pub use journal::SuperBlockHeader;
• pub use journal::SuperBlockRecord;
• pub use journal::SuperBlockRecordV5;
• pub use transaction::Mutation;

Modules

• allocator
• caching_object_handle
• directory
• graveyard
• journal
  The journal is implemented as an ever extending file which contains variable length records that describe mutations to be applied to various objects. The journal file consists of blocks, with a checksum at the end of each block, but otherwise it can be considered a continuous stream.
• object_manager
• project_id
• transaction
• volume
• writeback_cache

Structs

• DirectWriter
  Like object_handle::Writer, but allows custom transaction options to be set, and makes every write go directly to the handle in a transaction.
• EncryptedMutations
• ExtentKey
  ExtentKey is a child of ObjectKey for Object attributes that have attached extents (at time of writing this was only the used for file contents).
• HandleOptions
• NewChildStoreOptions
• ObjectAttributes
  Object-level attributes. Note that these are not the same as “attributes” in the ObjectValue::Attribute sense, which refers to an arbitrary data payload associated with an object. This naming collision is unfortunate.
• ObjectAttributesV5
• ObjectKey
  ObjectKey is a key in the object store.
• ObjectKeyV5
• ObjectStore
  An object store supports a file like interface for objects. Objects are keyed by a 64 bit identifier. And object store has to be backed by a parent object store (which stores metadata for the object store). The top-level object store (a.k.a. the root parent object store) is in-memory only.
• StoreInfo
• StoreObjectHandle
• Timestamp
  UNIX epoch based timestamp in the UTC timezone.

Enums

• AttributeKey
• EncryptionKeys
• ExtentValue
  ExtentValue is the payload for an extent in the object store, which describes where the extent is physically located.
• LockState
• ObjectDescriptor
  ObjectDescriptor is the set of possible records in the object store.
• ObjectKeyData
• ObjectKeyDataV5
• ObjectKind
• ObjectValue
  ObjectValue is the value of an item in the object store. Note that the tree stores deltas on objects, so these values describe deltas. Unless specified otherwise, a value indicates an insert/replace mutation.
• ObjectValueV5
• ProjectProperty
  For specifying what property of the project is being addressed.
• TrimMode
  Argument to the trim_some method.
• TrimResult
  Result of the trim_some method.

Constants

• BLOB_MERKLE_ATTRIBUTE_ID
  For Blobs in Fxfs, we store the merkle tree at a well-known attribute. TODO(fxbug.dev/122125): Is this the best place to store the merkle tree? What about inline with data?
• DEFAULT_DATA_ATTRIBUTE_ID
  The common case for extents which cover the data payload of some object.
• MAX_ENCRYPTED_MUTATIONS_SIZE
• MAX_STORE_INFO_SERIALIZED_SIZE

Traits

• HandleOwner
  StoreObjectHandle stores an owner that must implement this trait, which allows the handle to get back to an ObjectStore and provides a callback for creating a data buffer for the handle.

Functions

• load_store_info
  Loads store info.