iommu: Improve error handling when setting bus iommu
From: Heiko Stuebner <heiko@...> Date: Mon, 27 Oct 2014 12:11:46 +0100
Commit-Message
When some part of bus_set_iommu fails it should undo any made changes and not simply leave everything as is. This includes unregistering the bus notifier in iommu_bus_init when add_iommu_group fails and also setting the bus->iommu_ops back to NULL. Signed-off-by: Heiko Stuebner <heiko@...>
Patch-Comment
drivers/iommu/iommu.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-)
Statistics
- 16 lines added
- 2 lines removed
Changes
---------------------------- drivers/iommu/iommu.c -----------------------------
index ed8b048..b0e6b94 100644
@@ -818,7 +818,15 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
kfree(nb);
return err;
}
+
+ err = bus_for_each_dev(bus, NULL, &cb, add_iommu_group);
+ if (err) {
+ bus_unregister_notifier(bus, nb);
+ kfree(nb);
+ return err;
+ }
+
+ return 0;
}
/**
@@ -836,13 +844,19 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
*/
int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops)
{
+ int err;
+
if (bus->iommu_ops != NULL)
return -EBUSY;
bus->iommu_ops = ops;
/* Do IOMMU specific setup for this bus-type */
+ err = iommu_bus_init(bus, ops);
+ if (err)
+ bus->iommu_ops = NULL;
+
+ return err;
}
EXPORT_SYMBOL_GPL(bus_set_iommu);