FreeBSD: ATA-mkIII driver framework

[asg]

Wie Soren Schmidt auf @current mitteilte steht ein erster offizieller snapshot für ATA-mkIII zur Verfügung.

Folgende Neuerungen gibt es bei dem neuen Treiber für ATA:

o ATA is now fully newbus'd and split into modules.
This means that on a modern system you just load "atapci and ata"
to get the base support, and then one or more of the device
subdrivers "atadisk atapicd atapifd atapist ataraid".
All can be loaded/unloaded anytime, but for obvious reasons you
dont want to unload atadisk when you have mounted filesystems.

o The device identify part of the probe has been rewritten to fix
the problems with odd devices the old had, and to try to remove
so of the long delays some HW could provoke.

o SATA devices can be hot inserted/removed and devices will be created/
removed in /dev accordingly. NOTE only supported on controllers that
has this feature: Promise and Silicon Image for now.

o ATA RAID support has been rewritten and and now supports these
metadata formats:
"Adaptec HostRAID"
"Highpoint V2 RocketRAID"
"Highpoint V3 RocketRAID"
"Intel MatrixRAID"
"Integrated Technology Express"
"LSILogic V2 MegaRAID"
"LSILogic V3 MegaRAID"
"Promise FastTrak"
"Silicon Image Medley"

o The reinit code has been worked over to be much more robust.

o The timeout code has been overhauled for races.

o Lots of fixes for bugs found while doing the modulerization and
reviewing the old code.



Folgende Features fehlen:

o atapi-cd no longer has support for ATAPI changers. Todays its
much cheaper and alot faster to copy those CD images to disk
and serve them from there. Besides they dont seem to be made
anymore, maybe for that exact reason.

o ATA RAID can only read metadata not write them. This means that
arrays can be picked up from the BIOS, but they cannot be created
from FreeBSD. This is being worked on for the final release as is
RAID5 support for Promise/Highpoing/SiI controllers.

o The atapi-cam author has been informed and has had early access
to this work but so far atapicam is not supported with these
changes. However I do have my own atacam that puts both ATA and ATAPI
devices under CAM, but its really just academic at this point.

Das snapshot steht für RELENG_5 (STABLE) und CURRENT zur Verfügung und gibt es unter:

http://people.freebsd.org/~sos/ata-mk3j.diff-releng5.gz
http://people.freebsd.org/~sos/ata-mk3j.diff-current.gz
http://people.freebsd.org/~sos/ata-mk3j.tar.gz

Beide patches und das tarfile sind relativ zu /usr/src zu sehen.
Den Inhalt von sys/dev/ata/ sollte vor dem Entpacken gelöscht werden.

Es sind keine Änderungen in den vorhandenen configfiles notwendig.