Mohanlal Sukhadia University Udaipur 300301

1. Mohanlal Sukhadia University Udaipur 300301 University Of Science Class:-B.C.A 2nd year

2. PresentationTopic:- Kernal Module Of LINUX Operating System Presented By:- Nidhip Moyal Nishtha Singh

3. Q:- What is a Kernel? Answer:- The Kernel is a heart of an Operating System. The Kernel is responsible for maintaining all the important abstractions of the operating system, including such things as virtual memory and processes.

4. Q:- What is a Kernel Module? Answer:-Modules are pieces of code that can be loaded and unloaded into the kernel upon demand. They extend the functionality of the kernel without the need to reboot the system. For example, one type of models is the device driver, which allows the kernel to access hardware connected to the system.

5. Use ofKernel Module:- • The Kernel’s Module interface to allow third parties to write and distribute, on their own terms, device drivers or file systems that could not be distributed under the GPL. • Kernel Modulesallow a Linux system to be set up with a standard, minimal kernel, without any extra device drivers built in.

6. Advantages of Kernel Module. • It gives flexibility to the system. • Saving of time and money. • Less complicated kernel.

7. Disadvantages of Kernel Module. • The only disadvantage of kernel module is that a user updates drives without updating kernel.

8. The module support under Linux has three components. • The module management. • 2. The driver registration. • 3. The conflict-resolution mechanism.

9. Module Management:-It allows modules to be loaded into memory and to talk to the rest of the kernel. There are three components of the Module Management. • 1) The Kernel Reference:- In this point the system must also make sure that any reference the modules makes to kernel symbols or entry points are updated to point to the correct location in the kernel’s address space. • 2) Loading of the module:- The loading of the module is performed in two stages. • The modules-loader utility asks the kernel to reserve a continuous area of virtual kernel memory for the module. The kernel returns the address of the memory allocated, and the loader utility can use this address to relocate the module’s machine code to the correct loading address. • The system call then passes the module, plus any symbol table that the new module wants to export, to the kernel.

10. 3) Module Requestor:- The kernel defines a communication interface to which a module management program can connect. With this connection established, the kernel will inform the management process whenever a process request a device driver, file system, or network service that is not currently loaded and will give the manager the opportunity to load that service.

11. 2) Driver Registration:- Once a module is loaded, the kernel maintains the dynamic tables of all known drivers and provides a set of routine to allow drivers to be added to or remove from these table any time. • A module may register many types of drivers and may register more then one driver it wishes. Registration tables includes the following items: • Device drivers:- These drivers include character device, block device, and network interface devices. • File system:- The file system may be anything that implements Linux’s virtual-file-system calling routines. It might implement a format for storing files on a disk, but it might equally well be a network file system. • Network protocols:-A module may implement an entire networking protocol, such as IPX, or simply a new set of packet-filtering rules for a network firewall. • Binary format:-This format specifies a way of recognizing, and loading, a new type of EXE file.

12. 3) Conflict Resolution:-Linux provides a central conflict-resolution mechanism to help arbitrate access to certain hardware resources. It aims are as follows: • To prevent modules for clashing over access to hardware resources • To prevent auto probes-device –driver probes that auto detect device configuration-from interfacing with existing device drivers • To resolve conflicts among multiple drivers trying to access the same hardware.

13. Thank You.