| Message ID | 12-v6-e8114faedade+425-iommu_all_defdom_jgg@nvidia.com |
|---|---|
| State | New |
| Headers | show |
| Series | iommu: Make default_domain's mandatory | expand |
On 2023/8/3 8:07, Jason Gunthorpe wrote: > All ARM64 iommu drivers should support IOMMU_DOMAIN_DMA to enable > dma-iommu.c. > > tegra is blocking dma-iommu usage, and also default_domain's, because it > wants an identity translation. This is needed for some device quirk. The > correct way to do this is to support IDENTITY domains and use > ops->def_domain_type() to return IOMMU_DOMAIN_IDENTITY for only the quirky > devices. > > Add support for IOMMU_DOMAIN_DMA and force IOMMU_DOMAIN_IDENTITY mode for > everything so no behavior changes. > > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> > --- > drivers/iommu/tegra-smmu.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c > index f63f1d4f0bd10f..6cba034905edbf 100644 > --- a/drivers/iommu/tegra-smmu.c > +++ b/drivers/iommu/tegra-smmu.c > @@ -276,7 +276,7 @@ static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type) > { > struct tegra_smmu_as *as; > > - if (type != IOMMU_DOMAIN_UNMANAGED) > + if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA) > return NULL; > > as = kzalloc(sizeof(*as), GFP_KERNEL); > @@ -989,6 +989,12 @@ static int tegra_smmu_def_domain_type(struct device *dev) > } > > static const struct iommu_ops tegra_smmu_ops = { > + /* > + * FIXME: For now we want to run all translation in IDENTITY mode, > + * better would be to have a def_domain_type op do this for just the > + * quirky device. > + */ > + .default_domain = &tegra_smmu_identity_domain, tegra_smmu_def_domain_type() has already forced the core to use ops->identity_domain, why do we still need ops->default_domain? > .identity_domain = &tegra_smmu_identity_domain, > .def_domain_type = &tegra_smmu_def_domain_type, > .domain_alloc = tegra_smmu_domain_alloc, Best regards, baolu
On Mon, Aug 14, 2023 at 01:08:39PM +0800, Baolu Lu wrote: > > @@ -989,6 +989,12 @@ static int tegra_smmu_def_domain_type(struct device *dev) > > } > > static const struct iommu_ops tegra_smmu_ops = { > > + /* > > + * FIXME: For now we want to run all translation in IDENTITY mode, > > + * better would be to have a def_domain_type op do this for just the > > + * quirky device. > > + */ > > + .default_domain = &tegra_smmu_identity_domain, > > tegra_smmu_def_domain_type() has already forced the core to use > ops->identity_domain, why do we still need ops->default_domain? This looks like it is just some cruft from an earlier version that did not have tegra_smmu_def_domain_type(), I deleted it Thanks, Jason
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c index f63f1d4f0bd10f..6cba034905edbf 100644 --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -276,7 +276,7 @@ static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type) { struct tegra_smmu_as *as; - if (type != IOMMU_DOMAIN_UNMANAGED) + if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA) return NULL; as = kzalloc(sizeof(*as), GFP_KERNEL); @@ -989,6 +989,12 @@ static int tegra_smmu_def_domain_type(struct device *dev) } static const struct iommu_ops tegra_smmu_ops = { + /* + * FIXME: For now we want to run all translation in IDENTITY mode, + * better would be to have a def_domain_type op do this for just the + * quirky device. + */ + .default_domain = &tegra_smmu_identity_domain, .identity_domain = &tegra_smmu_identity_domain, .def_domain_type = &tegra_smmu_def_domain_type, .domain_alloc = tegra_smmu_domain_alloc,
All ARM64 iommu drivers should support IOMMU_DOMAIN_DMA to enable dma-iommu.c. tegra is blocking dma-iommu usage, and also default_domain's, because it wants an identity translation. This is needed for some device quirk. The correct way to do this is to support IDENTITY domains and use ops->def_domain_type() to return IOMMU_DOMAIN_IDENTITY for only the quirky devices. Add support for IOMMU_DOMAIN_DMA and force IOMMU_DOMAIN_IDENTITY mode for everything so no behavior changes. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> --- drivers/iommu/tegra-smmu.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)