Explaining the role of the block layer
The block layer is tasked with implementing the kernel interfaces that enable filesystems to interact with storage devices. In the context of accessing physical storage, applications use block devices, and any requests to access data on these devices are managed by the block layer. The kernel also contains a mapping layer just above the block layer. This layer provides a flexible and powerful way to map one block device to another, allowing for operations such as creating snapshots, encrypting data, and creating logical volumes that span multiple physical devices. The interfaces that are implemented in the block layer are central to managing physical storage in Linux. The device files for block devices are created in the /dev directory.
Like VFS, abstraction is the core function of the block layer. The VFS layer allows applications to make generic requests for interacting with files without having to worry about the underlying filesystem. In...
