On Thu, 20 Sep 2018 18:00:39 +0100
Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx> wrote:
> +
> +static int io_mm_attach(struct iommu_domain *domain, struct device
> *dev,
> + struct io_mm *io_mm, void *drvdata)
> +{
> + int ret;
> + bool attach_domain = true;
> + int pasid = io_mm->pasid;
> + struct iommu_bond *bond, *tmp;
> + struct iommu_sva_param *param = dev->iommu_param->sva_param;
> +
> + if (!domain->ops->mm_attach || !domain->ops->mm_detach)
> + return -ENODEV;
> +
> + if (pasid > param->max_pasid || pasid < param->min_pasid)
> + return -ERANGE;
> +
> + bond = kzalloc(sizeof(*bond), GFP_KERNEL);
> + if (!bond)
> + return -ENOMEM;
> +
> + bond->domain = domain;
> + bond->io_mm = io_mm;
> + bond->dev = dev;
> + bond->drvdata = drvdata;
> +
> + spin_lock(&iommu_sva_lock);
> + /*
> + * Check if this io_mm is already bound to the domain. In
> which case the
> + * IOMMU driver doesn't have to install the PASID table
> entry.
> + */
> + list_for_each_entry(tmp, &domain->mm_list, domain_head) {
> + if (tmp->io_mm == io_mm) {
> + attach_domain = false;
> + break;
> + }
> + }
> +
> + ret = domain->ops->mm_attach(domain, dev, io_mm,
> attach_domain);
> + if (ret) {
> + kfree(bond);
> + goto out_unlock;
> + }
> +
> + list_add(&bond->mm_head, &io_mm->devices);
> + list_add(&bond->domain_head, &domain->mm_list);
> + list_add(&bond->dev_head, ¶m->mm_list);
> +
I am trying to understand if mm_list is needed for both per device and
per domain. Do you always unbind and detach domain? Seems device could
use the domain->mm_list to track all mm's, true?
