On Wed, 26 Apr 2017 18:12:00 +0800
"Liu, Yi L" <yi.l.liu@xxxxxxxxx> wrote:
> From: "Liu, Yi L" <yi.l.liu@xxxxxxxxxxxxxxx>
>
> When a SVM capable device is assigned to a guest, the first level page
> tables are owned by the guest and the guest PASID table pointer is
> linked to the device context entry of the physical IOMMU.
>
> Host IOMMU driver has no knowledge of caching structure updates unless
> the guest invalidation activities are passed down to the host. The
> primary usage is derived from emulated IOMMU in the guest, where QEMU
> can trap invalidation activities before pass them down the
> host/physical IOMMU. There are IOMMU architectural specific actions
> need to be taken which requires the generic APIs introduced in this
> patch to have opaque data in the tlb_invalidate_info argument.
>
> Signed-off-by: Liu, Yi L <yi.l.liu@xxxxxxxxxxxxxxx>
> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> ---
> drivers/iommu/iommu.c | 13 +++++++++++++
> include/linux/iommu.h | 16 ++++++++++++++++
> 2 files changed, 29 insertions(+)
>
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index f2da636..ca7cff2 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -1153,6 +1153,19 @@ int iommu_unbind_pasid_table(struct iommu_domain *domain, struct device *dev)
> }
> EXPORT_SYMBOL_GPL(iommu_unbind_pasid_table);
>
> +int iommu_do_invalidate(struct iommu_domain *domain,
> + struct device *dev, struct tlb_invalidate_info *inv_info)
> +{
> + int ret = 0;
> +
> + if (unlikely(domain->ops->do_invalidate == NULL))
> + return -ENODEV;
> +
> + ret = domain->ops->do_invalidate(domain, dev, inv_info);
> + return ret;
nit, ret is unnecessary.
> +}
> +EXPORT_SYMBOL_GPL(iommu_do_invalidate);
> +
> 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 491a011..a48e3b75 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -140,6 +140,11 @@ struct pasid_table_info {
> __u8 opaque[];/* IOMMU-specific details */
> };
>
> +struct tlb_invalidate_info {
> + __u32 model;
> + __u8 opaque[];
> +};
I'm wondering if 'model' is really necessary here, shouldn't this
function only be called if a bind_pasid_table() succeeded, and then the
model would be set at that time?
This also needs to be uapi since you're expecting a user to provide it
to vfio. The opaque data needs to be fully specified (relative to
uapi) per model.
> +
> #ifdef CONFIG_IOMMU_API
>
> /**
> @@ -215,6 +220,8 @@ struct iommu_ops {
> struct pasid_table_info *pasidt_binfo);
> int (*unbind_pasid_table)(struct iommu_domain *domain,
> struct device *dev);
> + int (*do_invalidate)(struct iommu_domain *domain,
> + struct device *dev, struct tlb_invalidate_info *inv_info);
>
> unsigned long pgsize_bitmap;
> };
> @@ -240,6 +247,9 @@ 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 int iommu_do_invalidate(struct iommu_domain *domain,
> + struct device *dev, struct tlb_invalidate_info *inv_info);
> +
> 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);
> @@ -626,6 +636,12 @@ int iommu_unbind_pasid_table(struct iommu_domain *domain, struct device *dev)
> return -EINVAL;
> }
>
> +static inline int iommu_do_invalidate(struct iommu_domain *domain,
> + struct device *dev, struct tlb_invalidate_info *inv_info)
> +{
> + return -EINVAL;
> +}
> +
> #endif /* CONFIG_IOMMU_API */
>
> #endif /* __LINUX_IOMMU_H */
