Porting Unix to the 386: A Practical Approach

William & Lynne Jolitz

Started open source UNIX.

Appeared in part as a 17 article magazine series in 1991-1992.

Documented the "how, what, why, who, when" of porting BSD to the 386.

Done while BSD was becoming "open source".

Porting Unix to the 386: A Practical Approach - kernel address space

kernel address space:

Per-Process Data Structures

A UNIX legacy, the "u." or per-process data structure, which held the kernel-related data of a process, was present on 386BSD prior to February 1991.

386 Virtual Memory Address Translation Mechanism

The 386 Paging Memory Management allocates memory in 4KB and 4MB allocation units. This impacts the way programs execute and share file data.

Processor Support -- i386.c

We initialized the processor with initial descriptor and page tables - one needs to run with the tables before activating memory/interrupt kernel functions.