Struct OffsetMap

pub struct OffsetMap { /* private fields */ }

Remaps the offset of block requests based on an internal map, and truncates long requests. TODO(https://fxbug.dev/402515764): For now, this just supports a single entry in the map, which is all that is required for GPT partitions. If we want to support this for FVM, we will need to support multiple entries, which requires changing the block server to support request splitting.

Implementations

impl OffsetMap

pub fn new( mapping: BlockOffsetMapping, max_transfer_blocks: Option<NonZero<u32>>, ) -> Self

An OffsetMap that remaps requests.

pub fn empty(max_transfer_blocks: Option<NonZero<u32>>) -> Self

An OffsetMap that just enforces maximum request sizes.

pub fn is_empty(&self) -> bool

pub fn adjust_request( &self, dev_offset: u64, length: u32, is_rw: bool, ) -> Option<(u64, u32)>

Adjusts the requested range, returning the new range. Returns None if the request would exceed the ranges known to OffsetMap.