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Date:   Thu, 28 Nov 2019 08:51:53 +0100
From:   "hch@lst.de" <hch@lst.de>
To:     Thomas Hellstrom <thellstrom@vmware.com>
Cc:     "hch@lst.de" <hch@lst.de>,
        "thomas.lendacky@amd.com" <thomas.lendacky@amd.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "christian.koenig@amd.com" <christian.koenig@amd.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH 2/2] dma-mapping: force unencryped devices are always
 addressing limited
Message-ID: <20191128075153.GD20659@lst.de>
References: <20191127144006.25998-1-hch@lst.de> <20191127144006.25998-3-hch@lst.de> <a95d9115fc2a80de2f97f001bbcd9aba6636e685.camel@vmware.com>
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On Wed, Nov 27, 2019 at 06:22:57PM +0000, Thomas Hellstrom wrote:
> >  bool dma_addressing_limited(struct device *dev)
> >  {
> > +	if (force_dma_unencrypted(dev))
> > +		return true;
> >  	return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
> >  			    dma_get_required_mask(dev);
> >  }
> 
> Any chance to have the case
> 
> (swiotlb_force == SWIOTLB_FORCE)
> 
> also included?

We have a hard time handling that in generic code.  Do we have any
good use case for SWIOTLB_FORCE not that we have force_dma_unencrypted?
I'd love to be able to get rid of it..