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Date: Mon, 17 Oct 2011 15:53:38 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 03/35] atapi: move GESN definitions to
	scsi-defs.h
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To: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-devel@nongnu.org

On 10/17/2011 03:41 PM, Kevin Wolf wrote:
> I'm not sure about the NCR_* constants. They happen to be shifted
> values, but the spec doesn't define them as such but has two separate
> tables for them.

Yeah, on the other hand the spec has hints that they are really the same 
thing:

1) one is called notification class request, the other is called 
notification class.  Using the same name is surprising since the SCSI 
spec usually cannot praised for its consistency.  For example the 
returned header includes a field called "supported event classes" 
(rather than for example "supported notification classes"), but the 
description refers explicitly to the same table used for the 
"notification class request" field.

2) "bit 0 is perpetually reserved" in the notification class request 
field, and the notification class field value "000" means "no requested 
event classes are supported".

Paolo