From: Arnd Bergmann <arnd@arndb.de>
To: Scott Wood <scottwood@freescale.com>
Subject: Re: [PATCH 7/7] [v2] drivers/misc: introduce Freescale hypervisor management driver
Date: Fri, 3 Jun 2011 17:28:43 +0200
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Cc: Timur Tabi <timur@freescale.com>, kumar.gala@freescale.com,
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On Thursday 02 June 2011, Scott Wood wrote:
> I wanted to have the hypervisor take an update dtb (we already have special
> meta-properties for things like deletion as part of the hv config
> mechanism).  But others on the project wanted to keep it simple, and so
> get/set property it was. :-/
> 
> It's unlikely to change at this point without a real need.
> 
> As for a filesystem interface, it's not a good match either. 
> You can't iterate over anything to read out the full tree from the hv.

kexec iterates over /proc/device-tree to create a dts blob.

> You can't delete anything. 

rm, rmdir

> You can't create empty nodes.

mkdir

> The hv interface was meant to enable some specific management actions,
> rather than to provide general device tree access.  This driver is a thin
> wrapper around the management hcalls.

A file system would be a slightly more abstract interface to do the
same thing, I gues.

> There would still be other ioctls needed for starting/stopping the
> partition, etc.

Right, although you could model them as a file interface as well.
KVMfs is one example doing that.

	Arnd
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