Messages in this thread |  | | From | Magnus Damm <> | Date | Thu, 20 Oct 2016 08:45:18 +0900 | Subject | Re: [PATCH v5 05/07] iommu/ipmmu-vmsa: Add new IOMMU_DOMAIN_DMA ops |
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Hi Joerg,
On Thu, Sep 22, 2016 at 11:45 PM, Joerg Roedel <joro@8bytes.org> wrote: > On Tue, Sep 20, 2016 at 10:44:46PM +0900, Magnus Damm wrote: >> +#ifdef CONFIG_IOMMU_DMA >> + >> +static struct iommu_domain *ipmmu_domain_alloc_dma(unsigned type) >> +{ >> + struct iommu_domain *io_domain; >> + >> + if (type != IOMMU_DOMAIN_DMA) >> + return NULL; >> + >> + io_domain = __ipmmu_domain_alloc(type); >> + if (io_domain) >> + iommu_get_dma_cookie(io_domain); >> + >> + return io_domain; >> +} >> + >> +static void ipmmu_domain_free_dma(struct iommu_domain *io_domain) >> +{ >> + iommu_put_dma_cookie(io_domain); >> + ipmmu_domain_free(io_domain); >> +} > >> [...] > >> +static const struct iommu_ops ipmmu_ops = { >> + .domain_alloc = ipmmu_domain_alloc_dma, >> + .domain_free = ipmmu_domain_free_dma, > > Okay, so when CONFIG_IOMMU_DMA is enabled, you only support allocation > of DMA domains, not UNMANAGED domains anymore. Is there a reason for > that?
Just historical reason migrating from UNMANAGED only to DMA only.
> You can reduce the #ifdef'ed coded by supporting both types of domains > and call into allocation-subfunctions for DMA and UNMANAGED domains. The > #ifdef could then only let the dma-allocation function return NULL. > > This would be much more compatible to what other IOMMU drivers do and > will allow VFIO usage in the future.
Thanks for your suggestion. I've now updated the code in V6, hopefully it would match your expectation better.
Cheers,
/ magnus
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