10 Mar
2023
10 Mar
'23
8:06 a.m.
From: Jason Gunthorpe jgg@nvidia.com Sent: Friday, March 10, 2023 1:21 AM
On Thu, Mar 09, 2023 at 09:50:18PM +0800, Baolu Lu wrote:
- if (cmd->flags || cmd->__reserved || !cmd->data_len)
return -EOPNOTSUPP;- idev = iommufd_get_device(ucmd, cmd->dev_id);
- if (IS_ERR(idev))
return PTR_ERR(idev);- ops = dev_iommu_ops(idev->dev);
- if (!ops || !ops->hw_info) {
dev_iommu_ops() will never return a NULL.
Need below check
dev->iommu && dev->iommu->iommu_dev
before dev_iommu_ops(). Perhaps something like below?
if (!dev->iommu || !dev->iommu->iommu_dev) return -EINVAL;
At this point the device has become owned through the ownership API, it absolutely has to have an iommu and an ops. No need to check anything.
ok. so just needs to check hw_info callback.