With the def_domain_type introduced, iommu default domain framework
is now able to determine a proper default domain for a group. Let's
use this to configure a group's default domain.
If unlikely a device requires a special default domain type other
than that in use, iommu probe procedure will either allocate a new
domain according to the specified domain type, or (if the group has
other devices sitting in it) change the default domain. The vendor
iommu driver which exposes the def_domain_type callback should
guarantee that there're no multiple devices in a same group requires
differnt types of default domain.
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com>
Signed-off-by: Lu Baolu <baolu...@linux.intel.com>
---
drivers/iommu/iommu.c | 103 ++++++++++++++++++++++++++++++++++++++++--
1 file changed, 100 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3e3528436e0b..8db670196706 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1361,6 +1361,89 @@ struct iommu_group *fsl_mc_device_group(struct device
*dev)
}
EXPORT_SYMBOL_GPL(fsl_mc_device_group);
+static int pre_def_domain_change(struct device *dev, void *data)
+{
+ struct iommu_group *group = data;
+
+ if (device_is_bound(dev))
+ return -EINVAL;
+
+ return iommu_group_create_direct_mappings(group, dev);
+}
+
+static int post_def_domain_change(struct device *dev, void *data)
+{
+ struct iommu_domain *domain = data;
+
+ return domain->ops->add_device(dev);
+}
+
+/**
+ * Changes the default domain of a group
+ *
+ * @group: The group for which the default domain should be changed
+ * @type: The new default domain type
+ *
+ * The caller should hold the group->mutex before call into this function.
+ * Returns 0 on success and error code on failure.
+ */
+static int iommu_group_change_def_domain(struct iommu_group *group, int type)
+{
+ struct iommu_domain *new, *old;
+ const struct iommu_ops *ops;
+ int ret;
+
+ 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) {
+ iommu_group_put(group);
+ return -ENOMEM;
+ }
+ new->type = type;
+ new->ops = ops;
+ new->pgsize_bitmap = old->pgsize_bitmap;
+ group->default_domain = new;
+ group->domain = new;
+
+ ret = __iommu_group_for_each_dev(group, group, pre_def_domain_change);
+ if (ret)
+ goto err_out;
+
+ ret = __iommu_attach_group(new, group);
+ if (ret)
+ goto err_out;
+
+ ret = __iommu_group_for_each_dev(group, new, post_def_domain_change);
+ if (ret)
+ goto err_out;
+
+ iommu_domain_free(old);
+ iommu_group_put(group);
+
+ return 0;
+
+err_out:
+ group->default_domain = old;
+ group->domain = old;
+ __iommu_attach_group(old, group);
+ iommu_domain_free(new);
+ iommu_group_put(group);
+
+ return ret;
+}
+
/**
* iommu_group_get_for_dev - Find or create the IOMMU group for a device
* @dev: target device
@@ -1375,6 +1458,7 @@ struct iommu_group *iommu_group_get_for_dev(struct device
*dev)
{
const struct iommu_ops *ops = dev->bus->iommu_ops;
struct iommu_group *group;
+ int dev_def_type = 0;
int ret;
group = iommu_group_get(dev);
@@ -1391,20 +1475,24 @@ struct iommu_group *iommu_group_get_for_dev(struct
device *dev)
if (IS_ERR(group))
return group;
+ if (ops->def_domain_type)
+ dev_def_type = ops->def_domain_type(dev);
+
/*
* Try to allocate a default domain - needs support from the
* IOMMU driver.
*/
if (!group->default_domain) {
struct iommu_domain *dom;
+ int type = dev_def_type ? : iommu_def_domain_type;
- dom = __iommu_domain_alloc(dev->bus, iommu_def_domain_type);
- if (!dom && iommu_def_domain_type != IOMMU_DOMAIN_DMA) {
+ dom = __iommu_domain_alloc(dev->bus, type);
+ if (!dom && type != IOMMU_DOMAIN_DMA) {
dom = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA);
if (dom) {
dev_warn(dev,
"failed to allocate default IOMMU
domain of type %u; falling back to IOMMU_DOMAIN_DMA",
- iommu_def_domain_type);
+ type);
}
}
@@ -1418,6 +1506,15 @@ struct iommu_group *iommu_group_get_for_dev(struct
device *dev)
DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE,
&attr);
}
+ } else if (dev_def_type &&
+ dev_def_type != group->default_domain->type) {
+ mutex_lock(&group->mutex);
+ ret = iommu_group_change_def_domain(group, dev_def_type);
+ mutex_unlock(&group->mutex);
+ if (ret) {
+ iommu_group_put(group);
+ return ERR_PTR(ret);
+ }
}
ret = iommu_group_add_device(group, dev);
--
2.17.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
