| Subject | Re: dynamic DMA-buf sharing between devices | From | Christian König <> | Date | Thu, 18 Apr 2019 12:57:44 +0200 |
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Am 18.04.19 um 11:13 schrieb Daniel Vetter: > On Tue, Apr 16, 2019 at 08:38:29PM +0200, Christian König wrote: >> Hi everybody, >> >> core idea in this patch set is that DMA-buf importers can now provide an optional invalidate callback. Using this callback and the reservation object exporters can now avoid pinning DMA-buf memory for a long time while sharing it between devices. >> >> I've already send out an older version roughly a year ago, but didn't had time to further look into cleaning this up. >> >> The last time a major problem was that we would had to fix up all drivers implementing DMA-buf at once. >> >> Now I avoid this by allowing mappings to be cached in the DMA-buf attachment and so driver can optionally move over to the new interface one by one. >> >> This is also a prerequisite to my patchset enabling sharing of device memory with DMA-buf. > Ok, with the discussions and thinking I think this design is solid and > should work out. Bunch of api and documentation polishing still to do, to > make sure we have really clear semantics and as little room as possible > for misunderstanding - refactoring a mess in dma-buf is a lot more tricky > than just ttm, there's a lot more users.
Yeah, I'm pretty aware of that after changing all the users of the map API to use a structure for the parameters.
Well at least it's not UAPI :)
Christian
> -Daniel
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