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Date: Thu, 1 May 2008 17:29:13 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Christoph Hellwig <hch@infradead.org>
Cc: Michael Buesch <mb@bu3sch.de>, Jesse Barnes <jbarnes@virtuousgeek.org>,
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Subject: Re: [PATCH 0/3] Add API for weak DMA masks
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> Why do we need it?  Is the call to set the 32bit mask when it fails
> a too big burden for the driver author?

We have tons of drivers that go

	try and set 64bit 
	oh failed
	try and set 32 bit
	oh worked

When what most actually want is "set it no more than this wide" - a
request or even a "pci_set_best_mask()" type idea.

Lots less code duplication.