Re: [PATCH v8 3/5] iommufd: Add IOMMU_GET_HW_INFO

[Nicolin Chen <nicolinc@nvidia.com>]

On Fri, Aug 18, 2023 at 12:04:29AM +0000, Liu, Yi L wrote:

> > From: Nicolin Chen <nicolinc@nvidia.com>
> > Sent: Friday, August 18, 2023 5:08 AM
> >
> > Looks like Yi's latest code has not addressed these comments.
> 
> Yeah. Not yet. In progress to incorporate them. 😊

I fixed them all in my local tree. I'm finalizing with alloc_user.
Let me send my branch after that, and you can edit upon :)

> > > > +int iommufd_get_hw_info(struct iommufd_ucmd *ucmd)
> > > > +{
> > > > +     struct iommu_hw_info *cmd = ucmd->cmd;
> > > > +     void __user *user_ptr = u64_to_user_ptr(cmd->data_uptr);
> > > > +     const struct iommu_ops *ops;
> > > > +     struct iommufd_device *idev;
> > > > +     unsigned int data_len;
> > > > +     unsigned int copy_len;
> > > > +     void *data = NULL;
> > [..]
> > > > +     } else {
> > > > +             cmd->out_data_type = IOMMU_HW_INFO_TYPE_NONE;
> > > > +             data_len = 0;
> > > > +             data = NULL;
> > >
> > > data is already initialized as NULL.
> 
> Probably we can set data_len = 0 and the out_data_type to _NONE is
> the top as well. Any preference?

Yea we can do that. Let me change it.

Thanks
Nic