With a vIOMMU object, use space can flush any IOMMU related cache that can
be directed via a vIOMMU object. It is similar to the IOMMU_HWPT_INVALIDATE
uAPI, but can cover a wider range than IOTLB, e.g. device/desciprtor cache.
Allow hwpt_id of the iommu_hwpt_invalidate structure to carry a viommu_id,
and reuse the IOMMU_HWPT_INVALIDATE uAPI for vIOMMU invalidations. Drivers
can define different structures for vIOMMU invalidations v.s. HWPT ones.
Update the uAPI, kdoc, and selftest case accordingly.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
include/uapi/linux/iommufd.h | 9 ++++---
drivers/iommu/iommufd/hw_pagetable.c | 32 +++++++++++++++++++------
tools/testing/selftests/iommu/iommufd.c | 4 ++--
3 files changed, 33 insertions(+), 12 deletions(-)
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index b699ecb7aa9c..c2c5f49fdf17 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -730,7 +730,7 @@ struct iommu_hwpt_vtd_s1_invalidate {
/**
* struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE)
* @size: sizeof(struct iommu_hwpt_invalidate)
- * @hwpt_id: ID of a nested HWPT for cache invalidation
+ * @hwpt_id: ID of a nested HWPT or a vIOMMU, for cache invalidation
* @data_uptr: User pointer to an array of driver-specific cache invalidation
* data.
* @data_type: One of enum iommu_hwpt_invalidate_data_type, defining the data
@@ -741,8 +741,11 @@ struct iommu_hwpt_vtd_s1_invalidate {
* Output the number of requests successfully handled by kernel.
* @__reserved: Must be 0.
*
- * Invalidate the iommu cache for user-managed page table. Modifications on a
- * user-managed page table should be followed by this operation to sync cache.
+ * Invalidate iommu cache for user-managed page table or vIOMMU. Modifications
+ * on a user-managed page table should be followed by this operation, if a HWPT
+ * is passed in via @hwpt_id. Other caches, such as device cache or descriptor
+ * cache can be flushed if a vIOMMU is passed in via the @hwpt_id field.
+ *
* Each ioctl can support one or more cache invalidation requests in the array
* that has a total size of @entry_len * @entry_num.
*
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index fd260a67b82c..5301ba69fb8a 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -483,7 +483,7 @@ int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
.entry_len = cmd->entry_len,
.entry_num = cmd->entry_num,
};
- struct iommufd_hw_pagetable *hwpt;
+ struct iommufd_object *pt_obj;
u32 done_num = 0;
int rc;
@@ -497,17 +497,35 @@ int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
goto out;
}
- hwpt = iommufd_get_hwpt_nested(ucmd, cmd->hwpt_id);
- if (IS_ERR(hwpt)) {
- rc = PTR_ERR(hwpt);
+ pt_obj = iommufd_get_object(ucmd->ictx, cmd->hwpt_id, IOMMUFD_OBJ_ANY);
+ if (IS_ERR(pt_obj)) {
+ rc = PTR_ERR(pt_obj);
goto out;
}
+ if (pt_obj->type == IOMMUFD_OBJ_HWPT_NESTED) {
+ struct iommufd_hw_pagetable *hwpt =
+ container_of(pt_obj, struct iommufd_hw_pagetable, obj);
+
+ rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,
+ &data_array);
+ } else if (pt_obj->type == IOMMUFD_OBJ_VIOMMU) {
+ struct iommufd_viommu *viommu =
+ container_of(pt_obj, struct iommufd_viommu, obj);
+
+ if (!viommu->ops || !viommu->ops->cache_invalidate) {
+ rc = -EOPNOTSUPP;
+ goto out_put_pt;
+ }
+ rc = viommu->ops->cache_invalidate(viommu, &data_array);
+ } else {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
- rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,
- &data_array);
done_num = data_array.entry_num;
- iommufd_put_object(ucmd->ictx, &hwpt->obj);
+out_put_pt:
+ iommufd_put_object(ucmd->ictx, pt_obj);
out:
cmd->entry_num = done_num;
if (iommufd_ucmd_respond(ucmd, sizeof(*cmd)))
diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index 93255403dee4..44fbc7e5aa2e 100644
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -362,9 +362,9 @@ TEST_F(iommufd_ioas, alloc_hwpt_nested)
EXPECT_ERRNO(EBUSY,
_test_ioctl_destroy(self->fd, parent_hwpt_id));
- /* hwpt_invalidate only supports a user-managed hwpt (nested) */
+ /* hwpt_invalidate does not support a parent hwpt */
num_inv = 1;
- test_err_hwpt_invalidate(ENOENT, parent_hwpt_id, inv_reqs,
+ test_err_hwpt_invalidate(EINVAL, parent_hwpt_id, inv_reqs,
IOMMU_HWPT_INVALIDATE_DATA_SELFTEST,
sizeof(*inv_reqs), &num_inv);
assert(!num_inv);
--
2.43.0On Fri, Oct 25, 2024 at 04:50:34PM -0700, Nicolin Chen wrote:
> @@ -497,17 +497,35 @@ int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
> goto out;
> }
>
> - hwpt = iommufd_get_hwpt_nested(ucmd, cmd->hwpt_id);
> - if (IS_ERR(hwpt)) {
> - rc = PTR_ERR(hwpt);
> + pt_obj = iommufd_get_object(ucmd->ictx, cmd->hwpt_id, IOMMUFD_OBJ_ANY);
> + if (IS_ERR(pt_obj)) {
> + rc = PTR_ERR(pt_obj);
> goto out;
> }
> + if (pt_obj->type == IOMMUFD_OBJ_HWPT_NESTED) {
> + struct iommufd_hw_pagetable *hwpt =
> + container_of(pt_obj, struct iommufd_hw_pagetable, obj);
> +
> + rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,
> + &data_array);
> + } else if (pt_obj->type == IOMMUFD_OBJ_VIOMMU) {
> + struct iommufd_viommu *viommu =
> + container_of(pt_obj, struct iommufd_viommu, obj);
> +
> + if (!viommu->ops || !viommu->ops->cache_invalidate) {
> + rc = -EOPNOTSUPP;
> + goto out_put_pt;
> + }
> + rc = viommu->ops->cache_invalidate(viommu, &data_array);
> + } else {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
Given the test in iommufd_viommu_alloc_hwpt_nested() is:
if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED ||
(!viommu->ops->cache_invalidate &&
!hwpt->domain->ops->cache_invalidate_user)))
{
We will crash if the user passes a viommu allocated domain as
IOMMUFD_OBJ_HWPT_NESTED since the above doesn't check it.
I suggest we put the required if (ops..) -EOPNOTSUPP above and remove
the ops->cache_invalidate checks from both WARN_ONs.
Jason
On Tue, Oct 29, 2024 at 04:09:41PM -0300, Jason Gunthorpe wrote:
> On Fri, Oct 25, 2024 at 04:50:34PM -0700, Nicolin Chen wrote:
> > @@ -497,17 +497,35 @@ int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
> > goto out;
> > }
> >
> > - hwpt = iommufd_get_hwpt_nested(ucmd, cmd->hwpt_id);
> > - if (IS_ERR(hwpt)) {
> > - rc = PTR_ERR(hwpt);
> > + pt_obj = iommufd_get_object(ucmd->ictx, cmd->hwpt_id, IOMMUFD_OBJ_ANY);
> > + if (IS_ERR(pt_obj)) {
> > + rc = PTR_ERR(pt_obj);
> > goto out;
> > }
> > + if (pt_obj->type == IOMMUFD_OBJ_HWPT_NESTED) {
> > + struct iommufd_hw_pagetable *hwpt =
> > + container_of(pt_obj, struct iommufd_hw_pagetable, obj);
> > +
> > + rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,
> > + &data_array);
> > + } else if (pt_obj->type == IOMMUFD_OBJ_VIOMMU) {
> > + struct iommufd_viommu *viommu =
> > + container_of(pt_obj, struct iommufd_viommu, obj);
> > +
> > + if (!viommu->ops || !viommu->ops->cache_invalidate) {
> > + rc = -EOPNOTSUPP;
> > + goto out_put_pt;
> > + }
> > + rc = viommu->ops->cache_invalidate(viommu, &data_array);
> > + } else {
> > + rc = -EINVAL;
> > + goto out_put_pt;
> > + }
>
> Given the test in iommufd_viommu_alloc_hwpt_nested() is:
>
> if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED ||
> (!viommu->ops->cache_invalidate &&
> !hwpt->domain->ops->cache_invalidate_user)))
> {
>
> We will crash if the user passes a viommu allocated domain as
> IOMMUFD_OBJ_HWPT_NESTED since the above doesn't check it.
Ah, that was missed.
> I suggest we put the required if (ops..) -EOPNOTSUPP above and remove
> the ops->cache_invalidate checks from both WARN_ONs.
Ack. I will add hwpt->domain->ops check:
---------------------------------------------------------------------
if (pt_obj->type == IOMMUFD_OBJ_HWPT_NESTED) {
struct iommufd_hw_pagetable *hwpt =
container_of(pt_obj, struct iommufd_hw_pagetable, obj);
if (!hwpt->domain->ops ||
!hwpt->domain->ops->cache_invalidate_user) {
rc = -EOPNOTSUPP;
goto out_put_pt;
}
rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,
&data_array);
} else if (pt_obj->type == IOMMUFD_OBJ_VIOMMU) {
struct iommufd_viommu *viommu =
container_of(pt_obj, struct iommufd_viommu, obj);
if (!viommu->ops || !viommu->ops->cache_invalidate) {
rc = -EOPNOTSUPP;
goto out_put_pt;
}
rc = viommu->ops->cache_invalidate(viommu, &data_array);
} else {
---------------------------------------------------------------------
Thanks
Nicolin
> From: Nicolin Chen <nicolinc@nvidia.com> > Sent: Saturday, October 26, 2024 7:51 AM > > With a vIOMMU object, use space can flush any IOMMU related cache that > can > be directed via a vIOMMU object. It is similar to the > IOMMU_HWPT_INVALIDATE > uAPI, but can cover a wider range than IOTLB, e.g. device/desciprtor cache. > > Allow hwpt_id of the iommu_hwpt_invalidate structure to carry a viommu_id, > and reuse the IOMMU_HWPT_INVALIDATE uAPI for vIOMMU invalidations. > Drivers > can define different structures for vIOMMU invalidations v.s. HWPT ones. > > Update the uAPI, kdoc, and selftest case accordingly. > > Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> > Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
© 2016 - 2026 Red Hat, Inc.