2.15.2.linux Kernel source directory structure 2

This section then explains the various folders under the root of the kernel source code, and explains the functions of some important folders.

(1) Arch. Arch is an acronym for Architecture, meaning architecture. The Arch directory is a subdirectory of a number of CPUs with different architectures, such as ARM, where all the files of the CPU are in the Arch/arm directory, and all the files of the X86 CPU are in the Arch/x86 directory.
(2) block. English is the meaning of the block, in Linux blocks represent block devices (in blocks (the whole of multiple bytes, similar to sector) as the overall access to units, such as SD card, Inand, Nand, hard disk, etc. are block devices. You can almost assume that a block device is a storage device. The block directory is decentralized with some Linux storage systems for the management of blocks of device code.
(3) Crypto. The English meaning is encryption. This directory has a number of common cryptographic algorithms implemented in C language code. such as CRC32, MD5, SHA1 and so on.
(4) Documentation. There are some documents in it.
(5) drivers. Drive directory, which lists the driver source code for all hardware devices supported by the Linux kernel.
(6) firmware. Firmware. What is a firmware? Firmware is actually software, but this software is fixed to the IC running inside the called firmware. Just like the Irom code in s5pv210.
(7) fs. FS is the file system, which lists the implementation of various file systems supported by Linux.
(8) include. Header files directory, common (various CPU architectures common) header files are here. Some header files specific to each CPU architecture are in the Arch/arm/include directory and its subdirectories.
(9) Init. Init is the meaning of initialization, and the code in this directory is the code that initializes the kernel when the Linux kernel starts.
(Ten) IPC. IPC is the inter process commuication, interprocess communication, which is implemented by the Linux-supported IPC code.
(one) kernel. Kernel is the kernel, is the Linux kernel, so this folder is the kernel itself needs some code files.
() Lib. Lib is the meaning of the library, here are some common useful library functions, note that the library function here and the C language library function is not the same. In kernel programming, the C standard library function is not available, and the library function in the Lib directory is used to replace the standard library functions. For example, in the kernel to convert strings into numbers with atoi, but kernel programming can only use the Atoi function in the Lib directory, can not be used in the standard C language library atoi. For example, in the kernel to print information can not use printf, and to use PRINTK, this PRINTK is our Lib directory.
(mm). MM is the memory management, memory management, and the Linux management code is here.
() net. This directory is the network-related code, such as the TCP/IP protocol stack, etc. are here.
(scripts). Script, this directory is all script files, these script files are not used by the Linux kernel to work, but to assist the Linux kernel configuration compiled production. Instead of going into the script in this directory in detail, we'll focus on configuring and compiling the Linux kernel through the periphery.
(a) security. Security-related code. No need to worry.
() sound. Related to audio processing.
() tools. Some useful tools used in Linux
(+) usr. The directory is INITRAMFS related, and the Linux kernel boot-related, temporarily do not have to pipe.
(Virt). Kernel virtual machine related, temporarily without tube.

Summary: So many of the directories are closely related to the arch and drivers directory, and then the other is a bit relevant also include, block, MM, net, lib and other directories.

2.15.2.linux Kernel source directory structure 2