From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: Query regarding modifying the DMA Mask based on the available memory in the system
Date: Thu, 17 Apr 2008 16:44:37 +0200
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In-Reply-To: <1208441932.3150.4.camel@localhost.localdomain> (James Bottomley's message of "Thu, 17 Apr 2008 09:18:52 -0500")
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To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Prakash, Sathya" <Sathya.Prakash@lsi.com>, linux-scsi@vger.kernel.org

>
> For drivers that can alter their descriptor types, we have this
> function:
>
> dma_get_required_mask()

Are you sure we have it? It seems to be in drivers/base/platform.c
conditional on ARCH_HAS_DMA_GET_REQUIRED_MASK, but according to my
grep no architecture ever sets that flag.

I don't think it would be very hard to implement on x86 at least,
mind you. Just nobody seems to have done it so far.

-Andi