On Wed, 26 Apr 2017 18:11:58 +0800 "Liu, Yi L" <yi.l.liu@xxxxxxxxx> wrote: > From: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> > > Virtual IOMMU was proposed to support Shared Virtual Memory (SVM) use > case in the guest: > https://lists.gnu.org/archive/html/qemu-devel/2016-11/msg05311.html > > As part of the proposed architecture, when a SVM capable PCI > device is assigned to a guest, nested mode is turned on. Guest owns the > first level page tables (request with PASID) and performs GVA->GPA > translation. Second level page tables are owned by the host for GPA->HPA > translation for both request with and without PASID. > > A new IOMMU driver interface is therefore needed to perform tasks as > follows: > * Enable nested translation and appropriate translation type > * Assign guest PASID table pointer (in GPA) and size to host IOMMU > > This patch introduces new functions called iommu_(un)bind_pasid_table() > to IOMMU APIs. Architecture specific IOMMU function can be added later > to perform the specific steps for binding pasid table of assigned devices. > > This patch also adds model definition in iommu.h. It would be used to > check if the bind request is from a compatible entity. e.g. a bind > request from an intel_iommu emulator may not be supported by an ARM SMMU > driver. > > Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> > Signed-off-by: Liu, Yi L <yi.l.liu@xxxxxxxxxxxxxxx> > --- > drivers/iommu/iommu.c | 19 +++++++++++++++++++ > include/linux/iommu.h | 31 +++++++++++++++++++++++++++++++ > 2 files changed, 50 insertions(+) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index dbe7f65..f2da636 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -1134,6 +1134,25 @@ int iommu_attach_device(struct iommu_domain *domain, struct device *dev) > } > EXPORT_SYMBOL_GPL(iommu_attach_device); > > +int iommu_bind_pasid_table(struct iommu_domain *domain, struct device *dev, > + struct pasid_table_info *pasidt_binfo) > +{ > + if (unlikely(!domain->ops->bind_pasid_table)) > + return -EINVAL; > + > + return domain->ops->bind_pasid_table(domain, dev, pasidt_binfo); > +} > +EXPORT_SYMBOL_GPL(iommu_bind_pasid_table); > + > +int iommu_unbind_pasid_table(struct iommu_domain *domain, struct device *dev) > +{ > + if (unlikely(!domain->ops->unbind_pasid_table)) > + return -EINVAL; > + > + return domain->ops->unbind_pasid_table(domain, dev); > +} > +EXPORT_SYMBOL_GPL(iommu_unbind_pasid_table); > + > static void __iommu_detach_device(struct iommu_domain *domain, > struct device *dev) > { > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index 0ff5111..491a011 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -131,6 +131,15 @@ struct iommu_dm_region { > int prot; > }; > > +struct pasid_table_info { > + __u64 ptr; /* PASID table ptr */ > + __u64 size; /* PASID table size*/ > + __u32 model; /* magic number */ > +#define INTEL_IOMMU (1 << 0) > +#define ARM_SMMU (1 << 1) > + __u8 opaque[];/* IOMMU-specific details */ > +}; This needs to be in uapi since you're expecting a user to pass it > + > #ifdef CONFIG_IOMMU_API > > /** > @@ -159,6 +168,8 @@ struct iommu_dm_region { > * @domain_get_windows: Return the number of windows for a domain > * @of_xlate: add OF master IDs to iommu grouping > * @pgsize_bitmap: bitmap of all possible supported page sizes > + * @bind_pasid_table: bind pasid table pointer for guest SVM > + * @unbind_pasid_table: unbind pasid table pointer and restore defaults > */ > struct iommu_ops { > bool (*capable)(enum iommu_cap); > @@ -200,6 +211,10 @@ struct iommu_ops { > u32 (*domain_get_windows)(struct iommu_domain *domain); > > int (*of_xlate)(struct device *dev, struct of_phandle_args *args); > + int (*bind_pasid_table)(struct iommu_domain *domain, struct device *dev, > + struct pasid_table_info *pasidt_binfo); > + int (*unbind_pasid_table)(struct iommu_domain *domain, > + struct device *dev); > > unsigned long pgsize_bitmap; > }; > @@ -221,6 +236,10 @@ extern int iommu_attach_device(struct iommu_domain *domain, > struct device *dev); > extern void iommu_detach_device(struct iommu_domain *domain, > struct device *dev); > +extern int iommu_bind_pasid_table(struct iommu_domain *domain, > + struct device *dev, struct pasid_table_info *pasidt_binfo); > +extern int iommu_unbind_pasid_table(struct iommu_domain *domain, > + struct device *dev); > extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev); > extern int iommu_map(struct iommu_domain *domain, unsigned long iova, > phys_addr_t paddr, size_t size, int prot); > @@ -595,6 +614,18 @@ const struct iommu_ops *iommu_get_instance(struct fwnode_handle *fwnode) > return NULL; > } > > +static inline > +int iommu_bind_pasid_table(struct iommu_domain *domain, struct device *dev, > + struct pasid_table_info *pasidt_binfo) > +{ > + return -EINVAL; > +} > +static inline > +int iommu_unbind_pasid_table(struct iommu_domain *domain, struct device *dev) > +{ > + return -EINVAL; > +} > + > #endif /* CONFIG_IOMMU_API */ > > #endif /* __LINUX_IOMMU_H */
