Struct BlockPointsTo 

pub struct BlockPointsTo<M: MetaData> {
    lba: LogicalBlockAddress,
    b: Arc<SpinLock<[u8; 4096]>>,
    _m: PhantomData<M>,
}

A wrapper around a metadata block that resides at a specific logical block address (LBA).

BlockPointsTo provides safe, synchronized access to a disk-backed 4096-byte block, and associates the block with a specific metadata type M implementing the MetaData trait. Internally, it uses a SpinLock to protect concurrent access and associate with its metadata type without affecting layout.

This abstraction allows safe and typed access to the underlying bytes as metadata structures, while supporting transactional read/write operations.

Type Parameters

• M: The type of metadata this block contains. Must implement MetaData.

Fields

lba: LogicalBlockAddress

Logical block address (LBA) where this block resides on disk.

b: Arc<SpinLock<[u8; 4096]>>

The in-memory contents of the block, protected by a spinlock for concurrency.

_m: PhantomData<M>

Marker to associate this block with metadata type M.

Implementations

impl<M: MetaData> BlockPointsTo<M>

pub fn read(&self) -> BlockPointsToReadGuard<'_, M>

Acquires a read-only guard to the underlying block contents.

Returns

• BlockPointsToReadGuard: A read guard providing immutable access to the block’s contents, typed as metadata M.

This method locks the internal spinlock and returns a guard for safe, read-only access to the raw bytes of the metadata block.

pub fn write<'a, 'b, 'c>( &'a self, tx: &'b RunningTransaction<'c>, ) -> BlockPointsToWriteGuard<'a, 'b, 'c, M>

Acquires a write guard to the block, registering it with the given transaction.

Arguments

• tx: The currently running transaction used to log changes for durability and crash recovery.

Returns

• BlockPointsToWriteGuard: A write guard that allows mutation of the block’s contents and records the modification in the transaction.

This method is intended for use in metadata updates. The block is locked for exclusive access, and the transaction ensures write-ahead logging or journaling semantics for filesystem consistency.

pub fn reload(&self, disk: &Disk) -> Result<(), KernelError>

Reload in-memory structure to synchronize with on-disk structure

Trait Implementations

impl<M: Clone + MetaData> Clone for BlockPointsTo<M>

fn clone(&self) -> BlockPointsTo<M>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.