On Mon, 2016-06-13 at 18:43 -0300, Mauricio Faria de Oliveira wrote: > Hi Ben, > > On 06/13/2016 06:26 PM, Benjamin Herrenschmidt wrote: > > I've been thinking about this a bit... it might be worthwhile adding > > a dma_* call to query the approximate size of the IOMMU window, as > > a way for the device to adjust its requirements dynamically. > > Ok, cool; something like it was one of the options being discussed here. > > What do you mean by 'approximate'? Maybe the size of 'free regions' in > the pools? -- not sure because iiuic the window size is static / 2 gig, > so didn't get why (or of what) to provide an approximation (for).
Approximate wasn't a great choice of word but what I meant is: - The size doesn't mean you can do an allocation that size (pools layout etc..) - And it might be shared with another device (though less likely these days). > > Another option would be to use a dma_attr for silencing mapping errors > > which NVME could use provided it does handle them gracefully ... > > Ah, that's new. Interesting. Thanks for suggestion! Cheers, Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
