mirage-block-combinators

Block signatures and implementations for MirageOS using Lwt
IN THIS PACKAGE

Fast Fold over the bytes of a block device

This functor use seek operations to perform fast folds over block devices.

Parameters

module A : SEEKABLE

Signature

val mapped_s : f:( 'a -> int64 -> Cstruct.t -> 'a Lwt.t ) -> 'a -> A.t -> ( 'a, A.error ) result Lwt.t

Folds f across data blocks read sequentially from a block device. In contrast to fold_s, Fold.mapped_s will use knowledge about the underlying disk structure and will skip blocks which it knows contain only zeroes. Note it may still read blocks containing zeroes. The function f receives an accumulator, the sector number and a data buffer.

val unmapped_s : f:( 'a -> int64 -> int64 -> 'a Lwt.t ) -> 'a -> A.t -> ( 'a, A.error ) result Lwt.t

Folds f acc ofs len across offsets of unmapped data blocks read sequentially from the block device. Fold.unmapped_s will use knowledge about the underlying disk structure and will only fold across those blocks which are guaranteed to be zero i.e. those which are unmapped somehow.