On Mon, Jan 06, 2025 at 10:46:21AM -0800, Nicolin Chen wrote:
> On Mon, Jan 06, 2025 at 11:01:32AM +0800, Baolu Lu wrote:
> > Nit: I think it would be more readable to add a check in the vevent
> > reporting helper.
> >
> > diff --git a/drivers/iommu/iommufd/driver.c b/drivers/iommu/iommufd/driver.c
> > index 77c34f8791ef..ccada0ada5ff 100644
> > --- a/drivers/iommu/iommufd/driver.c
> > +++ b/drivers/iommu/iommufd/driver.c
> > @@ -86,6 +86,9 @@ int iommufd_viommu_report_event(struct iommufd_viommu
> > *viommu,
> > if (WARN_ON_ONCE(!data_len || !event_data))
> > return -EINVAL;
> >
> > + if (WARN_ON_ONCE(type != IOMMU_VEVENTQ_TYPE_ARM_SMMUV3))
> > + return -EINVAL;
> > +
>
> Hmm, that's a good point I think.
>
> > down_read(&viommu->veventqs_rwsem);
> >
> > veventq = iommufd_viommu_find_veventq(viommu, type);
> ^
> |
> We actually have been missing a type validation entirely, so the
> type could have been rejected by this function. Perhaps we should
> add a static list of supported types to struct iommufd_viommu_ops
> for drivers to report so that then the core could reject from the
> first place during a vEVENTQ allocation.
I added something like this. Will send a v5.
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
index 0c7a5894ba07..348179f3cf2a 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
@@ -399,9 +399,15 @@ static int arm_vsmmu_cache_invalidate(struct iommufd_viommu *viommu,
return ret;
}
+static bool arm_vsmmu_supports_veventq(unsigned int type)
+{
+ return type == IOMMU_VIOMMU_TYPE_ARM_SMMUV3;
+}
+
static const struct iommufd_viommu_ops arm_vsmmu_ops = {
.alloc_domain_nested = arm_vsmmu_alloc_domain_nested,
.cache_invalidate = arm_vsmmu_cache_invalidate,
+ .supports_veventq = arm_vsmmu_supports_veventq,
};
struct iommufd_viommu *arm_vsmmu_alloc(struct device *dev,
diff --git a/drivers/iommu/iommufd/eventq.c b/drivers/iommu/iommufd/eventq.c
index bf0c04f571a7..b5be629f38ed 100644
--- a/drivers/iommu/iommufd/eventq.c
+++ b/drivers/iommu/iommufd/eventq.c
@@ -555,6 +555,11 @@ int iommufd_veventq_alloc(struct iommufd_ucmd *ucmd)
viommu = iommufd_get_viommu(ucmd, cmd->viommu_id);
if (IS_ERR(viommu))
return PTR_ERR(viommu);
+
+ if (!viommu->ops || !viommu->ops->supports_veventq ||
+ !viommu->ops->supports_veventq(cmd->type))
+ return -EOPNOTSUPP;
+
down_write(&viommu->veventqs_rwsem);
if (iommufd_viommu_find_veventq(viommu, cmd->type)) {
diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h
index 6b3b46e382f8..55e71dca3664 100644
--- a/include/linux/iommufd.h
+++ b/include/linux/iommufd.h
@@ -117,6 +117,7 @@ struct iommufd_viommu {
* array->entry_num to report the number of handled requests.
* The data structure of the array entry must be defined in
* include/uapi/linux/iommufd.h
+ * @supports_veventq: Whether the vIOMMU supports a given vEVENTQ type
*/
struct iommufd_viommu_ops {
void (*destroy)(struct iommufd_viommu *viommu);
@@ -125,6 +126,7 @@ struct iommufd_viommu_ops {
const struct iommu_user_data *user_data);
int (*cache_invalidate)(struct iommufd_viommu *viommu,
struct iommu_user_data_array *array);
+ bool (*supports_veventq)(unsigned int type);
};
#if IS_ENABLED(CONFIG_IOMMUFD)
