Re: [PATCH v8 8/9] vfio/type1: Add domain at(de)taching group helpers

From: Alex Williamson
Date: Tue Mar 26 2019 - 13:42:40 EST


On Mon, 25 Mar 2019 09:30:35 +0800
Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> wrote:

> This adds helpers to attach or detach a domain to a
> group. This will replace iommu_attach_group() which
> only works for non-mdev devices.
>
> If a domain is attaching to a group which includes the
> mediated devices, it should attach to the iommu device
> (a pci device which represents the mdev in iommu scope)
> instead. The added helper supports attaching domain to
> groups for both pci and mdev devices.
>
> Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
> Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
> Signed-off-by: Sanjay Kumar <sanjay.k.kumar@xxxxxxxxx>
> Signed-off-by: Liu Yi L <yi.l.liu@xxxxxxxxx>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Reviewed-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx>
> ---
> drivers/vfio/vfio_iommu_type1.c | 84 ++++++++++++++++++++++++++++++---
> 1 file changed, 77 insertions(+), 7 deletions(-)


Acked-by: Alex Williamson <alex.williamson@xxxxxxxxxx>


> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 73652e21efec..ccc4165474aa 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -91,6 +91,7 @@ struct vfio_dma {
> struct vfio_group {
> struct iommu_group *iommu_group;
> struct list_head next;
> + bool mdev_group; /* An mdev group */
> };
>
> /*
> @@ -1298,6 +1299,75 @@ static bool vfio_iommu_has_sw_msi(struct iommu_group *group, phys_addr_t *base)
> return ret;
> }
>
> +static struct device *vfio_mdev_get_iommu_device(struct device *dev)
> +{
> + struct device *(*fn)(struct device *dev);
> + struct device *iommu_device;
> +
> + fn = symbol_get(mdev_get_iommu_device);
> + if (fn) {
> + iommu_device = fn(dev);
> + symbol_put(mdev_get_iommu_device);
> +
> + return iommu_device;
> + }
> +
> + return NULL;
> +}
> +
> +static int vfio_mdev_attach_domain(struct device *dev, void *data)
> +{
> + struct iommu_domain *domain = data;
> + struct device *iommu_device;
> +
> + iommu_device = vfio_mdev_get_iommu_device(dev);
> + if (iommu_device) {
> + if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
> + return iommu_aux_attach_device(domain, iommu_device);
> + else
> + return iommu_attach_device(domain, iommu_device);
> + }
> +
> + return -EINVAL;
> +}
> +
> +static int vfio_mdev_detach_domain(struct device *dev, void *data)
> +{
> + struct iommu_domain *domain = data;
> + struct device *iommu_device;
> +
> + iommu_device = vfio_mdev_get_iommu_device(dev);
> + if (iommu_device) {
> + if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
> + iommu_aux_detach_device(domain, iommu_device);
> + else
> + iommu_detach_device(domain, iommu_device);
> + }
> +
> + return 0;
> +}
> +
> +static int vfio_iommu_attach_group(struct vfio_domain *domain,
> + struct vfio_group *group)
> +{
> + if (group->mdev_group)
> + return iommu_group_for_each_dev(group->iommu_group,
> + domain->domain,
> + vfio_mdev_attach_domain);
> + else
> + return iommu_attach_group(domain->domain, group->iommu_group);
> +}
> +
> +static void vfio_iommu_detach_group(struct vfio_domain *domain,
> + struct vfio_group *group)
> +{
> + if (group->mdev_group)
> + iommu_group_for_each_dev(group->iommu_group, domain->domain,
> + vfio_mdev_detach_domain);
> + else
> + iommu_detach_group(domain->domain, group->iommu_group);
> +}
> +
> static int vfio_iommu_type1_attach_group(void *iommu_data,
> struct iommu_group *iommu_group)
> {
> @@ -1373,7 +1443,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> goto out_domain;
> }
>
> - ret = iommu_attach_group(domain->domain, iommu_group);
> + ret = vfio_iommu_attach_group(domain, group);
> if (ret)
> goto out_domain;
>
> @@ -1405,8 +1475,8 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> list_for_each_entry(d, &iommu->domain_list, next) {
> if (d->domain->ops == domain->domain->ops &&
> d->prot == domain->prot) {
> - iommu_detach_group(domain->domain, iommu_group);
> - if (!iommu_attach_group(d->domain, iommu_group)) {
> + vfio_iommu_detach_group(domain, group);
> + if (!vfio_iommu_attach_group(d, group)) {
> list_add(&group->next, &d->group_list);
> iommu_domain_free(domain->domain);
> kfree(domain);
> @@ -1414,7 +1484,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> return 0;
> }
>
> - ret = iommu_attach_group(domain->domain, iommu_group);
> + ret = vfio_iommu_attach_group(domain, group);
> if (ret)
> goto out_domain;
> }
> @@ -1440,7 +1510,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> return 0;
>
> out_detach:
> - iommu_detach_group(domain->domain, iommu_group);
> + vfio_iommu_detach_group(domain, group);
> out_domain:
> iommu_domain_free(domain->domain);
> out_free:
> @@ -1531,7 +1601,7 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
> if (!group)
> continue;
>
> - iommu_detach_group(domain->domain, iommu_group);
> + vfio_iommu_detach_group(domain, group);
> list_del(&group->next);
> kfree(group);
> /*
> @@ -1596,7 +1666,7 @@ static void vfio_release_domain(struct vfio_domain *domain, bool external)
> list_for_each_entry_safe(group, group_tmp,
> &domain->group_list, next) {
> if (!external)
> - iommu_detach_group(domain->domain, group->iommu_group);
> + vfio_iommu_detach_group(domain, group);
> list_del(&group->next);
> kfree(group);
> }