Re: [PATCH v2 2/6] iommu: Configure default domain with def_domain_type

[Lu Baolu]

Hi Joerg,

On 2020/3/19 22:03, Joerg Roedel wrote:
> Hi Baolu,
>
> On Sat, Mar 14, 2020 at 09:07:01AM +0800, Lu Baolu wrote:
> > +static int iommu_group_change_def_domain(struct iommu_group *group, int type)
> > +{
> > +	struct group_device *grp_dev, *temp;
> > +	struct iommu_domain *new, *old;
> > +	const struct iommu_ops *ops;
> > +	int ret = 0;
> > +
> > +	if ((type != IOMMU_DOMAIN_IDENTITY && type != IOMMU_DOMAIN_DMA) ||
> > +	    !group->default_domain || type == group->default_domain->type ||
> > +	    !group->default_domain->ops)
> > +		return -EINVAL;
> > +
> > +	if (group->domain != group->default_domain)
> > +		return -EBUSY;
> > +
> > +	iommu_group_ref_get(group);
> > +	old = group->default_domain;
> > +	ops = group->default_domain->ops;
> > +
> > +	/* Allocate a new domain of requested type. */
> > +	new = ops->domain_alloc(type);
> > +	if (!new) {
> > +		ret = -ENOMEM;
> > +		goto domain_out;
> > +	}
> > +	new->type = type;
> > +	new->ops = ops;
> > +	new->pgsize_bitmap = group->default_domain->pgsize_bitmap;
> > +
> > +	group->default_domain = new;
> > +	group->domain = new;
> > +	list_for_each_entry_safe(grp_dev, temp, &group->devices, list) {
> > +		struct device *dev;
> > +
> > +		dev = grp_dev->dev;
> > +		if (device_is_bound(dev)) {
> > +			ret = -EINVAL;
> > +			goto device_out;
> > +		}
> > +
> > +		iommu_group_create_direct_mappings(group, dev);
> > +		ret = __iommu_attach_device(group->domain, dev);
> > +		if (ret)
> > +			goto device_out;
>
> In case of a failure here with a group containing multiple devices, the
> other devices temporarily lose their mappings. Please only do the
> device_is_bound() check in the loop and the actual re-attachment of the
> group with a call to __iommu_attach_group().

Sure. I've post a v3 of this patch according to your comments here.
Please help to review.

Best regards,
baolu