Browse Prior Art Database

New Partition Methodology for IA-32 and New Platforms

IP.com Disclosure Number: IPCOM000123821D
Original Publication Date: 1999-May-01
Included in the Prior Art Database: 2005-Apr-05

Publishing Venue

IBM

Related People

Chang, DM: AUTHOR

Abstract

Disclosed is a methodology for the existing primary partition tables on Intel Architecture 32-bit (IA-32) platform and future platforms.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 19% of the total text.

New Partition Methodology for IA-32 and New Platforms

   Disclosed is a methodology for the existing primary
partition tables on Intel Architecture 32-bit (IA-32) platform and
future platforms.

   Problems start with DOS defining a partition tables on
fixed disk.  The following are DOS primary partition table and DOS
extended partition table data structures.

   Backgrounds: Sector or block is defined as 512 byte unit.

   DOS primary partition table data structure:

   It starts at offset 0x1BE of Master Boot Record (MBR).
(offset, length in byte) field-name
  ------------------------ --------------
  first entry (offset 0x1BE of MBR)
  (0, 1)                   boot indicator
                           Partition 1 begin
  (1, 1)                     head
  (2, 1)                     sector
  (3, 1)                   track or cylinder
  (4, 1)                   file system type
                           Partition 1 end
  (5, 1)                     head
  (6, 1)                     sector
  (7, 1)                   track or cylinder
  (8, 4)                   offset
  (12, 4)                  size
  second entry (offset 0x1CE of MBR)
  (16, 1)                  boot indicator
                           Partition 2 begin
  (17, 1)                    head
  (18, 1)                    sector
  (19, 1)                    track or cylinder
  (20, 1)                  file system type
                           Partition 2 end
  (21, 1)                    head
  (22, 1)                    sector
  (23, 1)                    track or cylinder
  (24, 4)                  offset
  (28, 4)                  size
  third entry (offset 0x1DE of MBR)
  (32, 1)                  boot indicator
                           Partition 3 begin
  (33, 1)                    head
  (34, 1)                    sector
  (35, 1)                    track or cylinder
  (36, 1)                  file system type
                           Partition 3 end
  (37, 1)                    head
  (38, 1)                    sector
  (39, 1)                    track or cylinder
  (40, 4)                  offset
  (44, 4)                  size
  fourth entry (offset 0x1EE of MBR)
  (48, 1)                  boot indicator
       ...