Re: [PATCH v2] dma-mapping: treat dev->bus_dma_mask as a DMA limit

From: Robin Murphy
Date: Tue Nov 26 2019 - 16:45:41 EST


On 2019-11-26 6:51 pm, Nicolas Saenz Julienne wrote:
On Mon, 2019-11-25 at 16:33 +0000, Robin Murphy wrote:
On 25/11/2019 7:44 am, Christoph Hellwig wrote:
On Sat, Nov 23, 2019 at 09:51:08AM -0700, Nathan Chancellor wrote:
Just as an FYI, this introduces a warning on arm32 allyesconfig for me:

I think the dma_limit argument to iommu_dma_alloc_iova should be a u64
and/or we need to use min_t and open code the zero exception.

Robin, Nicolas - any opinions?

Yeah, given that it's always held a mask I'm not entirely sure why it
was ever a dma_addr_t rather than a u64. Unless anyone else is desperate
to do it I'll get a cleanup patch ready for rc1.

Sounds good to me too

Robin, since I started the mess, I'll be happy to do it if it helps offloading
some work from you.

No worries - your change only exposed my original weird decision ;) On second look the patch was literally a trivial one-liner, so I've written it up already.

Cheers,
Robin.