Commit 1ea5440e authored by Thierry Reding's avatar Thierry Reding Committed by Joerg Roedel
Browse files

iommu/tegra-smmu: Prune IOMMU group when it is released 



In order to share groups between multiple devices we keep track of them
in a per-SMMU list. When an IOMMU group is released, a dangling pointer
to it stays around in that list. Fix this by implementing an IOMMU data
release callback for groups where the dangling pointer can be removed.

Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200806155404.3936074-4-thierry.reding@gmail.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 5b30fbfa

drivers/iommu/tegra-smmu.c

+13 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 


struct tegra_smmu_group {

	struct list_head list;

	struct tegra_smmu *smmu;

	const struct tegra_smmu_group_soc *soc;

	struct iommu_group *group;

};
@@ -813,6 +814,16 @@ tegra_smmu_find_group(struct tegra_smmu *smmu, unsigned int swgroup) 
	return NULL;

}



static void tegra_smmu_group_release(void *iommu_data)

{

	struct tegra_smmu_group *group = iommu_data;

	struct tegra_smmu *smmu = group->smmu;



	mutex_lock(&smmu->lock);

	list_del(&group->list);

	mutex_unlock(&smmu->lock);

}



static struct iommu_group *tegra_smmu_group_get(struct tegra_smmu *smmu,

						unsigned int swgroup)

{
@@ -840,6 +851,7 @@ static struct iommu_group *tegra_smmu_group_get(struct tegra_smmu *smmu, 
	}



	INIT_LIST_HEAD(&group->list);

	group->smmu = smmu;

	group->soc = soc;



	group->group = iommu_group_alloc();
@@ -849,6 +861,7 @@ static struct iommu_group *tegra_smmu_group_get(struct tegra_smmu *smmu, 
		return NULL;

	}



	iommu_group_set_iommudata(group->group, group, tegra_smmu_group_release);

	iommu_group_set_name(group->group, soc->name);

	list_add_tail(&group->list, &smmu->groups);

	mutex_unlock(&smmu->lock);