domain_alloc_user op already accepts user flags for domain allocation, add
a parent domain pointer and a driver specific user data support as well.
The user data would be tagged with a type for iommu drivers to add their
own driver specific user data per hw_pagetable.
Add a struct iommu_user_data as a bundle of data_ptr/data_len/type from an
iommufd core uAPI structure. Make the user data opaque to the core, since
a userspace driver must match the kernel driver. In the future, if drivers
share some common parameter, there would be a generic parameter as well.
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Co-developed-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
---
drivers/iommu/amd/iommu.c | 9 ++++++---
drivers/iommu/intel/iommu.c | 7 ++++++-
drivers/iommu/iommufd/hw_pagetable.c | 3 ++-
drivers/iommu/iommufd/selftest.c | 7 ++++++-
include/linux/iommu.h | 27 ++++++++++++++++++++++++---
5 files changed, 44 insertions(+), 9 deletions(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index caad10f9cee3..b399c5741378 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2219,12 +2219,15 @@ static struct iommu_domain *amd_iommu_domain_alloc(unsigned int type)
return domain;
}
-static struct iommu_domain *amd_iommu_domain_alloc_user(struct device *dev,
- u32 flags)
+static struct iommu_domain *
+amd_iommu_domain_alloc_user(struct device *dev, u32 flags,
+ struct iommu_domain *parent,
+ const struct iommu_user_data *user_data)
+
{
unsigned int type = IOMMU_DOMAIN_UNMANAGED;
- if (flags & ~IOMMU_HWPT_ALLOC_DIRTY_TRACKING)
+ if ((flags & ~IOMMU_HWPT_ALLOC_DIRTY_TRACKING) || parent || user_data)
return ERR_PTR(-EOPNOTSUPP);
return do_iommu_domain_alloc(type, dev, flags);
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index eb92a201cc0b..fe67f8d77b09 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4076,7 +4076,9 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type)
}
static struct iommu_domain *
-intel_iommu_domain_alloc_user(struct device *dev, u32 flags)
+intel_iommu_domain_alloc_user(struct device *dev, u32 flags,
+ struct iommu_domain *parent,
+ const struct iommu_user_data *user_data)
{
struct iommu_domain *domain;
struct intel_iommu *iommu;
@@ -4086,6 +4088,9 @@ intel_iommu_domain_alloc_user(struct device *dev, u32 flags)
(~(IOMMU_HWPT_ALLOC_NEST_PARENT | IOMMU_HWPT_ALLOC_DIRTY_TRACKING)))
return ERR_PTR(-EOPNOTSUPP);
+ if (parent || user_data)
+ return ERR_PTR(-EOPNOTSUPP);
+
iommu = device_to_iommu(dev, NULL, NULL);
if (!iommu)
return ERR_PTR(-ENODEV);
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index 6bce9af0cb8d..198ecbd536f7 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -108,7 +108,8 @@ iommufd_hwpt_paging_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
hwpt_paging->ioas = ioas;
if (ops->domain_alloc_user) {
- hwpt->domain = ops->domain_alloc_user(idev->dev, flags);
+ hwpt->domain =
+ ops->domain_alloc_user(idev->dev, flags, NULL, NULL);
if (IS_ERR(hwpt->domain)) {
rc = PTR_ERR(hwpt->domain);
hwpt->domain = NULL;
diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
index 068928ba7950..d71007234896 100644
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -241,7 +241,9 @@ static struct iommu_domain *mock_domain_alloc(unsigned int iommu_domain_type)
}
static struct iommu_domain *
-mock_domain_alloc_user(struct device *dev, u32 flags)
+mock_domain_alloc_user(struct device *dev, u32 flags,
+ struct iommu_domain *parent,
+ const struct iommu_user_data *user_data)
{
struct mock_dev *mdev = container_of(dev, struct mock_dev, dev);
struct iommu_domain *domain;
@@ -250,6 +252,9 @@ mock_domain_alloc_user(struct device *dev, u32 flags)
(~(IOMMU_HWPT_ALLOC_NEST_PARENT | IOMMU_HWPT_ALLOC_DIRTY_TRACKING)))
return ERR_PTR(-EOPNOTSUPP);
+ if (parent || user_data)
+ return ERR_PTR(-EOPNOTSUPP);
+
if ((flags & IOMMU_HWPT_ALLOC_DIRTY_TRACKING) &&
(mdev->flags & MOCK_FLAGS_DEVICE_NO_DIRTY))
return ERR_PTR(-EOPNOTSUPP);
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index bc303cb2af37..2ddd99f55471 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -265,6 +265,21 @@ struct iommu_dirty_ops {
struct iommu_dirty_bitmap *dirty);
};
+/**
+ * struct iommu_user_data - iommu driver specific user space data info
+ * @type: The data type of the user buffer
+ * @uptr: Pointer to the user buffer for copy_from_user()
+ * @len: The length of the user buffer in bytes
+ *
+ * A user space data is an uAPI that is defined in include/uapi/linux/iommufd.h
+ * @type, @uptr and @len should be just copied from an iommufd core uAPI struct.
+ */
+struct iommu_user_data {
+ unsigned int type;
+ void __user *uptr;
+ size_t len;
+};
+
/**
* struct iommu_ops - iommu ops and capabilities
* @capable: check capability
@@ -279,8 +294,12 @@ struct iommu_dirty_ops {
* parameters as defined in include/uapi/linux/iommufd.h.
* Unlike @domain_alloc, it is called only by IOMMUFD and
* must fully initialize the new domain before return.
- * Upon success, a domain is returned. Upon failure,
- * ERR_PTR must be returned.
+ * Upon success, if the @user_data is valid and the @parent
+ * points to a kernel-managed domain, the new domain must be
+ * IOMMU_DOMAIN_NESTED type; otherwise, the @parent must be
+ * NULL while the @user_data can be optionally provided, the
+ * new domain must support __IOMMU_DOMAIN_PAGING.
+ * Upon failure, ERR_PTR must be returned.
* @probe_device: Add device to iommu driver handling
* @release_device: Remove device from iommu driver handling
* @probe_finalize: Do final setup work after the device is added to an IOMMU
@@ -313,7 +332,9 @@ struct iommu_ops {
/* Domain allocation and freeing by the iommu driver */
struct iommu_domain *(*domain_alloc)(unsigned iommu_domain_type);
- struct iommu_domain *(*domain_alloc_user)(struct device *dev, u32 flags);
+ struct iommu_domain *(*domain_alloc_user)(
+ struct device *dev, u32 flags, struct iommu_domain *parent,
+ const struct iommu_user_data *user_data);
struct iommu_device *(*probe_device)(struct device *dev);
void (*release_device)(struct device *dev);
--
2.34.1
