iommu: store DT-probed IOMMU data privately

Since the data pointer in the DT node is public and may be overwritten
by conflicting code, move the DT-probed IOMMU ops to a private list
where they will be safe.

Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: added missing #include and missing ')']
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Robin Murphy 2014-12-05 13:41:02 +00:00 committed by Will Deacon
parent 4bb25789ed
commit a42a7a1fb5
2 changed files with 41 additions and 10 deletions

View File

@ -22,6 +22,7 @@
#include <linux/limits.h>
#include <linux/of.h>
#include <linux/of_iommu.h>
#include <linux/slab.h>
static const struct of_device_id __iommu_of_table_sentinel
__used __section(__iommu_of_table_end);
@ -94,6 +95,44 @@ int of_get_dma_window(struct device_node *dn, const char *prefix, int index,
}
EXPORT_SYMBOL_GPL(of_get_dma_window);
struct of_iommu_node {
struct list_head list;
struct device_node *np;
struct iommu_ops *ops;
};
static LIST_HEAD(of_iommu_list);
static DEFINE_SPINLOCK(of_iommu_lock);
void of_iommu_set_ops(struct device_node *np, struct iommu_ops *ops)
{
struct of_iommu_node *iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
if (WARN_ON(!iommu))
return;
INIT_LIST_HEAD(&iommu->list);
iommu->np = np;
iommu->ops = ops;
spin_lock(&of_iommu_lock);
list_add_tail(&iommu->list, &of_iommu_list);
spin_unlock(&of_iommu_lock);
}
struct iommu_ops *of_iommu_get_ops(struct device_node *np)
{
struct of_iommu_node *node;
struct iommu_ops *ops = NULL;
spin_lock(&of_iommu_lock);
list_for_each_entry(node, &of_iommu_list, list)
if (node->np == np) {
ops = node->ops;
break;
}
spin_unlock(&of_iommu_lock);
return ops;
}
struct iommu_ops *of_iommu_configure(struct device *dev)
{
struct of_phandle_args iommu_spec;

View File

@ -31,16 +31,8 @@ static inline struct iommu_ops *of_iommu_configure(struct device *dev)
#endif /* CONFIG_OF_IOMMU */
static inline void of_iommu_set_ops(struct device_node *np,
const struct iommu_ops *ops)
{
np->data = (struct iommu_ops *)ops;
}
static inline struct iommu_ops *of_iommu_get_ops(struct device_node *np)
{
return np->data;
}
void of_iommu_set_ops(struct device_node *np, struct iommu_ops *ops);
struct iommu_ops *of_iommu_get_ops(struct device_node *np);
extern struct of_device_id __iommu_of_table;