Module two_level_storage 

This module contains TwoLevelStateStorage, an implementation of MapStateStorage that is designed to work well on 64-bit machines. Currently it supports 48-bit address spaces, and many constants and data structures (such as Slab) are larger than i32::MAX. For this reason, this module is only available on 64-bit machines.

Structs

TwoLevelStateStorage

A two-level implementation of MapStateStorage.

Constants

LOG_MAPPABLE_BYTES 🔒

Logarithm of the address space size that TwoLevelStateStorage is able to handle. This is enough for ARM64, x86_64 and some other architectures. Feel free to increase it if we plan to support larger address spaces.

LOG_MAX_SLABS 🔒

Logarithm of maximum number of slabs.

LOG_MMAP_CHUNKS_PER_SLAB 🔒

Log number of chunks per slab.

LOG_MMAP_SLAB_BYTES 🔒

Log number of bytes per slab. For a two-level array, it is advisable to choose the arithmetic mean of LOG_MAPPABLE_BYTES and LOG_BYTES_IN_CHUNK in order to make MMAP_SLAB_BYTES the geometric mean of MAPPABLE_BYTES and BYTES_IN_CHUNK. This will balance the array size of TwoLevelStateStorage::slabs and Slab.

MAPPABLE_ADDRESS_LIMIT 🔒

The limit of mappable address

MAPPABLE_BYTES 🔒

Address space size a user-space program is allowed to use.

MAX_SLABS 🔒

maximum number of slabs.

MMAP_CHUNKS_PER_SLAB 🔒

Number of chunks per slab.

MMAP_SLAB_BYTES 🔒

Number of bytes per slab.

MMAP_SLAB_MASK 🔒

Mask for getting in-slab bits from an address. Invert this to get out-of-slab bits.

Type Aliases

Slab 🔒

The slab type. Each slab holds the MapState of multiple chunks.