Messages in this thread |  | | Date | Mon, 13 Jul 2020 14:14:54 +0100 | From | Will Deacon <> | Subject | Re: [PATCH v5 03/15] iommu/smmu: Report empty domain nesting info |
| |
On Sun, Jul 12, 2020 at 04:20:58AM -0700, Liu Yi L wrote: > This patch is added as instead of returning a boolean for DOMAIN_ATTR_NESTING, > iommu_domain_get_attr() should return an iommu_nesting_info handle. > > Cc: Will Deacon <will@kernel.org> > Cc: Robin Murphy <robin.murphy@arm.com> > Cc: Eric Auger <eric.auger@redhat.com> > Cc: Jean-Philippe Brucker <jean-philippe@linaro.org> > Suggested-by: Jean-Philippe Brucker <jean-philippe@linaro.org> > Signed-off-by: Liu Yi L <yi.l.liu@intel.com> > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> > --- > v4 -> v5: > *) address comments from Eric Auger. > --- > drivers/iommu/arm-smmu-v3.c | 29 +++++++++++++++++++++++++++-- > drivers/iommu/arm-smmu.c | 29 +++++++++++++++++++++++++++-- > 2 files changed, 54 insertions(+), 4 deletions(-) > > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index f578677..ec815d7 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -3019,6 +3019,32 @@ static struct iommu_group *arm_smmu_device_group(struct device *dev) > return group; > } > > +static int arm_smmu_domain_nesting_info(struct arm_smmu_domain *smmu_domain, > + void *data) > +{ > + struct iommu_nesting_info *info = (struct iommu_nesting_info *)data; > + unsigned int size; > + > + if (!info || smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED) > + return -ENODEV; > + > + size = sizeof(struct iommu_nesting_info); > + > + /* > + * if provided buffer size is smaller than expected, should > + * return 0 and also the expected buffer size to caller. > + */ > + if (info->size < size) { > + info->size = size; > + return 0; > + } > + > + /* report an empty iommu_nesting_info for now */ > + memset(info, 0x0, size); > + info->size = size; > + return 0; > +}
Have you verified that this doesn't break the existing usage of DOMAIN_ATTR_NESTING in drivers/vfio/vfio_iommu_type1.c?
Will
|  |