Exploring the Actual Filesystems Under the VFS

“Not all roots are buried down in the ground, some are at the top of a tree.” — Jinvirle

The kernel’s I/O stack can be broken down into three major sections: the virtual filesystem (VFS), the block layer, and the physical layer. The different flavors of filesystems supported by Linux can be thought of as the tail end of the VFS layer. The first two chapters gave us a decent understanding of the role of VFS, the major structures used by VFS, and how it aids the end user processes to interact with the different filesystems through a common file model. This means that we’ll now be able to use the word filesystem in its commonly accepted context. Finally.

In Chapter 2, we defined and explained some important data structures used by the VFS to define a generic framework for different filesystems. In order for a particular filesystem to be supported by the kernel, it should operate within the boundaries...