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        Jacob Pan <jacob.jun.pan@linux.intel.com>
Subject: Re: [PATCH v3 08/10] iommu/vt-d: Check whether device requires bounce
 buffer
To:     Christoph Hellwig <hch@lst.de>
References: <20190421011719.14909-1-baolu.lu@linux.intel.com>
 <20190421011719.14909-9-baolu.lu@linux.intel.com>
 <20190422164755.GC31181@lst.de>
From:   Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <76e35340-32c3-ee0d-5232-bd8800248402@linux.intel.com>
Date:   Tue, 23 Apr 2019 10:03:28 +0800
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Hi,

On 4/23/19 12:47 AM, Christoph Hellwig wrote:
> On Sun, Apr 21, 2019 at 09:17:17AM +0800, Lu Baolu wrote:
>> +static inline bool device_needs_bounce(struct device *dev)
>> +{
>> +	struct pci_dev *pdev = NULL;
>> +
>> +	if (intel_no_bounce)
>> +		return false;
>> +
>> +	if (dev_is_pci(dev))
>> +		pdev = to_pci_dev(dev);
>> +
>> +	return pdev ? pdev->untrusted : false;
>> +}
> 
> Again, this and the option should not be in a specific iommu driver.
> 

The option of whether bounce is ignored should be in the specific iommu
driver. Or any other thought?

Best regards,
Lu Baolu