# Re: \[PATCH 14/17\] iommu: remove DOMAIN\_ATTR\_DMA\_USE\_FLUSH\_QUEUE

- From: Christoph Hellwig \<hch@lst.de\>
- Date: 2021-03-15 08:34:38 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/03/8286038
- Thread: https://ratatoskr.run/kvm/2021/03/8285616/t.md

```text
On Fri, Mar 12, 2021 at 04:18:24PM +0000, Robin Murphy wrote:
>> Let me know what you think of the version here:
>>
>> http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/iommu-cleanup
>>
>> I'll happily switch the patch to you as the author if you're fine with
>> that as well.
>
> I still have reservations about removing the attribute API entirely and 
> pretending that io_pgtable_cfg is anything other than a SoC-specific 
> private interface,

I think a private inteface would make more sense.  For now I've just
condensed it down to a generic set of quirk bits and dropped the
attrs structure, which seems like an ok middle ground for now.  That
being said I wonder why that quirk isn't simply set in the device
tree?

> but the reworked patch on its own looks reasonable to 
> me, thanks! (I wasn't too convinced about the iommu_cmd_line wrappers 
> either...) Just iommu_get_dma_strict() needs an export since the SMMU 
> drivers can be modular - I consciously didn't add that myself since I was 
> mistakenly thinking only iommu-dma would call it.

Fixed.  Can I get your signoff for the patch?  Then I'll switch it to
over to being attributed to you.
```