In virtualization use case, when a guest is assigned
a PCI host device, protected by a virtual IOMMU on the guest,
the physical IOMMU must be programmed to be consistent with
the guest mappings. If the physical IOMMU supports two
translation stages it makes sense to program guest mappings
onto the first stage/level (ARM/Intel terminology) while the host
owns the stage/level 2.
In that case, it is mandated to trap on guest configuration
settings and pass those to the physical iommu driver.
This patch adds a new API to the iommu subsystem that allows
to set/unset the pasid table information.
A generic iommu_pasid_table_config struct is introduced in
a new iommu.h uapi header. This is going to be used by the VFIO
user API.
Signed-off-by: Jean-Philippe Brucker
Signed-off-by: Liu, Yi L
Signed-off-by: Ashok Raj
Signed-off-by: Jacob Pan
Signed-off-by: Eric Auger
---
v11 -> v12:
- add argsz, name the union
---
drivers/iommu/iommu.c | 67 ++
include/linux/iommu.h | 21
include/uapi/linux/iommu.h | 54 ++
3 files changed, 142 insertions(+)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index b53446bb8c6b..b061bf4c3bb2 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2171,6 +2171,73 @@ int iommu_uapi_sva_unbind_gpasid(struct iommu_domain
*domain, struct device *dev
}
EXPORT_SYMBOL_GPL(iommu_uapi_sva_unbind_gpasid);
+int iommu_attach_pasid_table(struct iommu_domain *domain,
+struct iommu_pasid_table_config *cfg)
+{
+ if (unlikely(!domain->ops->attach_pasid_table))
+ return -ENODEV;
+
+ return domain->ops->attach_pasid_table(domain, cfg);
+}
+
+int iommu_uapi_attach_pasid_table(struct iommu_domain *domain,
+ void __user *uinfo)
+{
+ struct iommu_pasid_table_config pasid_table_data = { 0 };
+ u32 minsz;
+
+ if (unlikely(!domain->ops->attach_pasid_table))
+ return -ENODEV;
+
+ /*
+* No new spaces can be added before the variable sized union, the
+* minimum size is the offset to the union.
+*/
+ minsz = offsetof(struct iommu_pasid_table_config, vendor_data);
+
+ /* Copy minsz from user to get flags and argsz */
+ if (copy_from_user(_table_data, uinfo, minsz))
+ return -EFAULT;
+
+ /* Fields before the variable size union are mandatory */
+ if (pasid_table_data.argsz < minsz)
+ return -EINVAL;
+
+ /* PASID and address granu require additional info beyond minsz */
+ if (pasid_table_data.version != PASID_TABLE_CFG_VERSION_1)
+ return -EINVAL;
+ if (pasid_table_data.format == IOMMU_PASID_FORMAT_SMMUV3 &&
+ pasid_table_data.argsz <
+ offsetofend(struct iommu_pasid_table_config,
vendor_data.smmuv3))
+ return -EINVAL;
+
+ /*
+* User might be using a newer UAPI header which has a larger data
+* size, we shall support the existing flags within the current
+* size. Copy the remaining user data _after_ minsz but not more
+* than the current kernel supported size.
+*/
+ if (copy_from_user((void *)_table_data + minsz, uinfo + minsz,
+ min_t(u32, pasid_table_data.argsz,
sizeof(pasid_table_data)) - minsz))
+ return -EFAULT;
+
+ /* Now the argsz is validated, check the content */
+ if (pasid_table_data.config < 1 && pasid_table_data.config > 3)
+ return -EINVAL;
+
+ return domain->ops->attach_pasid_table(domain, _table_data);
+}
+EXPORT_SYMBOL_GPL(iommu_uapi_attach_pasid_table);
+
+void iommu_detach_pasid_table(struct iommu_domain *domain)
+{
+ if (unlikely(!domain->ops->detach_pasid_table))
+ return;
+
+ domain->ops->detach_pasid_table(domain);
+}
+EXPORT_SYMBOL_GPL(iommu_detach_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 b95a6f8db6ff..464fcbecf841 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -223,6 +223,8 @@ struct iommu_iotlb_gather {
* @cache_invalidate: invalidate translation caches
* @sva_bind_gpasid: bind guest pasid and mm
* @sva_unbind_gpasid: unbind guest pasid and mm
+ * @attach_pasid_table: attach a pasid table
+ * @detach_pasid_table: detach the pasid table
* @def_domain_type: device default domain type, return value:
* - IOMMU_DOMAIN_IDENTITY: must use an identity domain
* - IOMMU_DOMAIN_DMA: must use a dma domain
@@ -287,6 +289,9 @@ struct iommu_ops {
void *drvdata);
void (*sva_unbind)(struct iommu_sva *handle);
u32 (*sva_get_pasid)(struct iommu_sva *handle);
+ int (*attach_pasid_table)(struct
