Re: IDE HPA

From: Bill Davidsen
Date: Wed Sep 07 2005 - 09:48:42 EST


Jeff Garzik wrote:

It seems to me that one should write an ATA-specific Device Mapper driver, which layers on top of an ATA disk. The driver obtains the starting location of HPA, then exports two block devices: one for the primary data area, and one for the HPA.

I've stayed out of this, but that sounds like a perfect solution to move the choice back to the user. However, installers still need to be aware of it at initial Linux install, and give the user some rational options:
- ignore it
- leave alone but visible
- blow it away and use the whole drive

It feels as if that's where the future disposition needs to be made. I do like treating the HPA as a separate drive though.

For situations where we want the start Linux philosophy -- Linux exports 100% of the hardware capability -- no DM layer needs to be used. For situations where its better to treat the HPA as a separate and distinct area, the DM driver would come in handy.

This follows the same philosophy as fakeraid (BIOS RAID): we simply export the entire disk, and Device Mapper (google for 'dmraid') handles the vendor-proprietary RAID metadata.

--
-bill davidsen (davidsen@xxxxxxx)
"The secret to procrastination is to put things off until the
last possible moment - but no longer" -me
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