LINUX System : Lecture 6

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LINUX System Lecture 6

• Bong-Soo Sohn

Lecture notes acknowledgement The design of
UNIX Operating System
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Architecture of the UNIX
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Libraries (1)
user programs
libraries
trap
user Level kernel Level
system call interface
file subsystem
buffer cache
hardware control
hardware
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File Subsystem (1)
user programs
libraries
trap
user Level kernel Level
system call interface
file subsystem
buffer cache
hardware control
hardware
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File Subsystem (2)

• Managing files
• Allocating file space
• Administering free space
• Controlling access to files
• Retrieving data for users
• Interact with set of system calls
• open, close, read, write, state, chown, chmod

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Buffering Mechanism (1)
user programs
libraries
trap
user Level kernel Level
system call interface
file subsystem
buffer cache
hardware control
hardware
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Buffering Mechanism (2)

• Interact with block I/O device drivers to
  initiate data transfer to and from kernel.

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Process Control Subsystem (1)
user programs
libraries
trap
user Level kernel Level
system call interface
file subsystem
buffer cache
hardware control
hardware
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Process Control Subsystem (2)

• Responsible for process synchronization.
• Interprocess communication (IPC)
• Memory management
• Process scheduling
• Interact with set of system calls
• fork, exec, exit, wait, brk, signal

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Process Control Subsystem (3)

• Memory management module
• Control the allocation of memory
• Scheduler module
• Allocate the CPU to processes
• Interprocess communication
• There are several forms.

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Hardware Control (1)
user programs
libraries
trap
user Level kernel Level
system call interface
file subsystem
buffer cache
hardware control
hardware
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Hardware Control (2)

• Responsible for handling interrupts and for
  communicating with the machine.