Shulou(Shulou.com)06/02 Report--

This article will explain in detail what the linux file system is, and the content of the article is of high quality, so the editor will share it for you as a reference. I hope you will have a certain understanding of the relevant knowledge after reading this article.

Linux file system

The file in the Linux file system is a collection of data. The file system contains not only the data in the file, but also the structure of the file system. All the files, directories, soft connections and file protection information seen by Linux users and programs are stored in it.

File system

In Linux, normal files and catalog files are saved on disks or tapes called block physical devices. A Linux system supports several physical disks, each of which can define one or more file systems. (analogy to microcomputer disk partition). Each file system consists of a sequence of logical blocks, and a logical disk space is generally divided into several parts with different uses, namely, boot block, super block, inode area, data area and so on.

Boot block: at the beginning of a file system, usually a sector in which the bootstrap is stored to read in and start the operating system; super block: used to record the management information of the file system. A particular file system defines a specific super block; the inode area (Inode): a file or directory occupies an Inode. The first index node is the root node of the file system. With the root node, one file system can be hung on the non-leaf node of another; data area: used to store file data or manage data.

The earliest file system type introduced by Linux is MINIX. The MINIX file system is defined by the MINIX operating system and has some limitations, such as the file name is up to 14 characters and the file length is 64m bytes. The first file system designed specifically for Linux was EXT (Extended File System), but the most popular one is EXT4.

The second generation extended file system was designed by Rey Card and its goal is to provide a powerful extensible file system for Linux. It is also the most successfully designed file system in the Linux world. The super block of EXT2 can be accessed through the super block of VFS (struct ext2_sb_info ext2_sb), and the inode of EXT2 can be accessed through the inode of VFS (struct ext2_inode_info ext2_i).

The source code of the file system EXT2 is in the / usr/src/linux/fs/ext2 directory, and its data structure is defined in the file / usr/src/linux/include/linux/ext2_fs.h and the files ext2_fs_i.h and ext2_fs_sb.h in the same directory.

The EXT2 file system divides the logical partition it occupies into block groups (block group), as shown in the following figure:

On the linux file system to share here, I hope that the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.