Browse Prior Art Database

Non-Restrictive Shared Physical Device Adapter Mechanism

IP.com Disclosure Number: IPCOM000114367D
Original Publication Date: 1994-Dec-01
Included in the Prior Art Database: 2005-Mar-28
Document File: 2 page(s) / 44K

Publishing Venue

IBM

Related People

Bugg, A: AUTHOR [+6]

Abstract

In a distributed environment, servers may attach multiple print control units, using multiple channel adapters. The physical adapters must be accessable by different non-printer device drivers in a concurrent fashion, by defining an addressible intermediate child 'virtual device' identifier which is inherently tied to the parent 'actual device' or physical channel adapter.

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This is the abbreviated version, containing approximately 67% of the total text.

Non-Restrictive Shared Physical Device Adapter Mechanism

      In a distributed environment, servers may attach multiple print
control units, using multiple channel adapters.  The physical
adapters must be accessable by different non-printer device drivers
in a concurrent fashion, by defining an addressible intermediate
child 'virtual device' identifier which is inherently tied to the
parent 'actual device' or physical channel adapter.

      This is achieved with a method of addressing and inclusion of
multiple device driver types to establish a dialog with multiple
channel adapter card devices.  A child device is defined which allows
several ('n') device drivers to be assigned to a single physical
adapter.

      A parent device, called the channel adapter, (e.g., chna1,
chna2...etc., for card 1, card 2) is configured with a methodology
which defines an object data element in the AIX* ODM database.  A
virtual device driver is defined which 'appears' to the operating
system as though it were a real device at system load time.

      A child is defined for chna1, chna2, etc. Each child can be
either an Advanced Function Printer (AFP) driver or a tape device
driver or any other device driver.  During boot (IPL), (assuming
multiple cards in the host), each unique card which is defined with a
unique card identifier (as a typical example, each 370 card has a
common id.  This id tells the configuration management system in ODM
which device driver to load), f...