[dpdk-dev] [PATCH v10 3/9] linuxapp/eal_pci: get iommu class

[Tan, Jianfeng]

Hi,

Nice patch series. But I still have a small question about below flag.


On 10/6/2017 7:03 PM, Santosh Shukla wrote:
> Get iommu class of PCI device on the bus and returns preferred iova
> mapping mode for that bus.
>
> Patch also introduces RTE_PCI_DRV_IOVA_AS_VA drv flag.
> Flag used when driver needs to operate in iova=va mode.
>
Does this flag indicate a must to use VA as IOVA, or a nice-to-have one? 
In detail, above commit log says, "needs to operate in iova=va mode", 
but the comment in the patch indicates this flag means "driver supports 
IOVA as VA".

If it's the latter case, I would suppose all drivers support to use VA 
as IOVA, if the NICs are binded to vfio-pci (iommu mode). Please correct 
me if I'm wrong.

Thanks,
Jianfeng