iommu/exynos: Rework and fix internal locking
This patch reworks locking in the exynos_iommu_attach/detach_device
functions to ensure that all entries of the sysmmu_drvdata and
exynos_iommu_owner structure are updated under the respective spinlocks,
while runtime pm functions are called without any spinlocks held.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 52ded84..0423dff 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -769,10 +769,12 @@ static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
+ spin_lock(&data->lock);
__sysmmu_disable(data);
data->pgtable = 0;
data->domain = NULL;
list_del_init(&data->domain_node);
+ spin_unlock(&data->lock);
}
spin_unlock_irqrestore(&domain->lock, flags);
@@ -810,17 +812,22 @@ static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
if (!has_sysmmu(dev) || owner->domain != iommu_domain)
return;
+ list_for_each_entry(data, &owner->controllers, owner_node) {
+ __sysmmu_disable(data);
+ pm_runtime_put(data->sysmmu);
+ }
+
spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
- __sysmmu_disable(data);
+ spin_lock(&data->lock);
data->pgtable = 0;
data->domain = NULL;
list_del_init(&data->domain_node);
- pm_runtime_put(data->sysmmu);
+ spin_unlock(&data->lock);
}
+ owner->domain = NULL;
spin_unlock_irqrestore(&domain->lock, flags);
- owner->domain = NULL;
dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__,
&pagetable);
@@ -841,18 +848,22 @@ static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
if (owner->domain)
exynos_iommu_detach_device(owner->domain, dev);
+ spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry(data, &owner->controllers, owner_node) {
+ spin_lock(&data->lock);
data->pgtable = pagetable;
data->domain = domain;
+ list_add_tail(&data->domain_node, &domain->clients);
+ spin_unlock(&data->lock);
+ }
+ owner->domain = iommu_domain;
+ spin_unlock_irqrestore(&domain->lock, flags);
+
+ list_for_each_entry(data, &owner->controllers, owner_node) {
pm_runtime_get_sync(data->sysmmu);
__sysmmu_enable(data);
-
- spin_lock_irqsave(&domain->lock, flags);
- list_add_tail(&data->domain_node, &domain->clients);
- spin_unlock_irqrestore(&domain->lock, flags);
}
- owner->domain = iommu_domain;
dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__,
&pagetable);