[PATCH V1 6/6] arm/xen: Assign xen-grant DMA ops for xen-grant DMA devices

Oleksandr olekstysh at gmail.com
Sun Apr 24 09:07:23 PDT 2022


On 23.04.22 19:42, Christoph Hellwig wrote:

Hello Christoph

> On Fri, Apr 22, 2022 at 07:51:03PM +0300, Oleksandr Tyshchenko wrote:
>>   static inline void xen_setup_dma_ops(struct device *dev)
>>   {
>>   #ifdef CONFIG_XEN
>> -	if (xen_swiotlb_detect())
>> +	if (arch_has_restricted_virtio_memory_access() &&
>> +			xen_is_grant_dma_device(dev))
>> +		xen_grant_setup_dma_ops(dev);
>> +	else if (xen_swiotlb_detect())
> I don't think that arch_has_restricted_virtio_memory_access
> check should be there as it still is a bit of a layering violation.

Well, I will remove it then (and update commit description).

For virtualized but non-virtio devices, it is not needed at all. For the 
virtio devices, this check is already present at 
virtio.c:virtio_features_ok()



>
-- 
Regards,

Oleksandr Tyshchenko




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