Drivers and the Kernel1

Drivers and the kernel: 

Drivers and the kernel 1- 1 Drivers and the kernel UNIX system has three layers: The hardware The operating system kernel The user-level programs Kernel Kernel hides the hardware, provides a abstract, high-level programming interface Process Signal and semaphores Virtual memory The filesystem Interprocess communication Kernel contains device drivers that manage its interaction with specific pieces of hardware. Size of kernel

Kernel types: 

Drivers and the kernel 1- 2 Kernel types Provide the kernel with explicit information about the hardware Depend on kernel prospects for devices on their own Solaris: almost completely modular kernel HP-UX: supports a relatively small and well-defined hardware base FreeBSD: must be told explicitly at kernel compilation time about device Linux: limited module support

Kernel types: 

Drivers and the kernel 1- 3 Kernel types Kernel build directory and location by system System Build Directory Kernel Solaris /kernel/unix HP-UX /stand /stand/vmunix Linux /usr/src/linux /vmlinuz or /boot/vmlinuz FreeBSD /usr/src/sys /kernel

Why Configure the kernel: 

Drivers and the kernel 1- 4 Why Configure the kernel Generic kernel Many device drivers Optional packages Tailor the kernel for your need Less memory Well-tuned configuration Add support for new types of device Some system is simple Some may need to several steps. Read this: Building the kernel is not difficult; its just difficult to fix when you break it. Get a good reference book for your OS