Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 426a2738 authored by Joerg Roedel's avatar Joerg Roedel
Browse files

iommu: Limit iommu_attach/detach_device to devices with their own group 



This patch changes the behavior of the iommu_attach_device
and iommu_detach_device functions. With this change these
functions only work on devices that have their own group.
For all other devices the iommu_group_attach/detach
functions must be used.

Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 53723dc5

drivers/iommu/iommu.c

+67 −4
Original line number Diff line number Diff line
@@ -433,6 +433,17 @@ void iommu_group_remove_device(struct device *dev) 
}

EXPORT_SYMBOL_GPL(iommu_group_remove_device);



static int iommu_group_device_count(struct iommu_group *group)

{

	struct iommu_device *entry;

	int ret = 0;



	list_for_each_entry(entry, &group->devices, list)

		ret++;



	return ret;

}



/**

 * iommu_group_for_each_dev - iterate over each device in the group

 * @group: the group
@@ -969,7 +980,8 @@ void iommu_domain_free(struct iommu_domain *domain) 
}

EXPORT_SYMBOL_GPL(iommu_domain_free);



int iommu_attach_device(struct iommu_domain *domain, struct device *dev)

static int __iommu_attach_device(struct iommu_domain *domain,

				 struct device *dev)

{

	int ret;

	if (unlikely(domain->ops->attach_dev == NULL))
@@ -980,9 +992,38 @@ int iommu_attach_device(struct iommu_domain *domain, struct device *dev) 
		trace_attach_device_to_domain(dev);

	return ret;

}



int iommu_attach_device(struct iommu_domain *domain, struct device *dev)

{

	struct iommu_group *group;

	int ret;



	group = iommu_group_get(dev);

	/* FIXME: Remove this when groups a mandatory for iommu drivers */

	if (group == NULL)

		return __iommu_attach_device(domain, dev);



	/*

	 * We have a group - lock it to make sure the device-count doesn't

	 * change while we are attaching

	 */

	mutex_lock(&group->mutex);

	ret = -EINVAL;

	if (iommu_group_device_count(group) != 1)

		goto out_unlock;



	ret = __iommu_attach_device(domain, dev);



out_unlock:

	mutex_unlock(&group->mutex);

	iommu_group_put(group);



	return ret;

}

EXPORT_SYMBOL_GPL(iommu_attach_device);



void iommu_detach_device(struct iommu_domain *domain, struct device *dev)

static void __iommu_detach_device(struct iommu_domain *domain,

				  struct device *dev)

{

	if (unlikely(domain->ops->detach_dev == NULL))

		return;
@@ -990,6 +1031,28 @@ void iommu_detach_device(struct iommu_domain *domain, struct device *dev) 
	domain->ops->detach_dev(domain, dev);

	trace_detach_device_from_domain(dev);

}



void iommu_detach_device(struct iommu_domain *domain, struct device *dev)

{

	struct iommu_group *group;



	group = iommu_group_get(dev);

	/* FIXME: Remove this when groups a mandatory for iommu drivers */

	if (group == NULL)

		return __iommu_detach_device(domain, dev);



	mutex_lock(&group->mutex);

	if (iommu_group_device_count(group) != 1) {

		WARN_ON(1);

		goto out_unlock;

	}



	__iommu_detach_device(domain, dev);



out_unlock:

	mutex_unlock(&group->mutex);

	iommu_group_put(group);

}

EXPORT_SYMBOL_GPL(iommu_detach_device);



/*
@@ -1006,7 +1069,7 @@ static int iommu_group_do_attach_device(struct device *dev, void *data) 
{

	struct iommu_domain *domain = data;



	return iommu_attach_device(domain, dev);

	return __iommu_attach_device(domain, dev);

}



int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group)
@@ -1020,7 +1083,7 @@ static int iommu_group_do_detach_device(struct device *dev, void *data) 
{

	struct iommu_domain *domain = data;



	iommu_detach_device(domain, dev);

	__iommu_detach_device(domain, dev);



	return 0;

}