Doug Maxey wrote:

On Tue, 27 Jul 2004 11:31:15 EDT, Jeff Garzik wrote:

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 What I would like is input on the general strategy that should be
 taken to modify the controller/adapter and device stack to:

 1) be first class modules, where all controllers/adapters are
    capable of being loaded and unloaded.  This is directed mostly at
    IDE/Southbridge controller/adapter devices.

this is already the case in IDE and libata

I would have to differ with you here.  From conversations and fairly
(2 or 3 months ago) experience, the IDE core is not capable of being
unloaded.

As long as the low-level driver can be unloaded, that's sufficient for 
hardware- and device-hotplug.

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 2) extend that support to all child devices; disk, optical,
    and tape.

this is already the case in IDE and SCSI

Educational question, what would I be looking for when grokking code
to see this is in place?

Just general refcounting / module support code.

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 3) be part of mainline.

this is already the case

Yes, the drivers are in the mainline.  Just not sure of how many
platforms will have non-pluggable controllers that need to have them
hot-plugged. :-)

The PCI API is a hotplug API.  Whether the underlying controller is 
hotpluggable or not is largely irrelevant to low-level drivers.

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 The items I perceive at the top of the issue list are:

 - The primary platforms for IDE/ATA devices are x86 based, and
   certainly do not care about having this capability.

incorrect

Ok, please delineate.  Working off the assumption that 95+% of the
systems that run Linux are x86 based, and have a single partition for
the system. In other words, no virtual processors, where each is
totally separate from the other.

That's completely irrelevant.  libata and the IDE core work without 
change on x86 and non-x86 systems.

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 - Where should this capability go?  Fork a subset of IDE
   controllers, and put them under the arch specific dir?
   Or include all devices?

there is nothing arch-specific about this

Again, going back to my original premise, that is, which platforms do
you foresee needing this capability?  I know that all should have
eventually.

All platforms should be considered hotplug.

	Jeff