iommu: Improve error handling when setting bus iommu

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@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Heiko Stübner 2014-10-29 01:22:56 +01:00 committed by Joerg Roedel
parent 38ec010d9b
commit d7da6bdc32

View File

@ -818,7 +818,15 @@ static int iommu_bus_init(struct bus_type *bus, const struct iommu_ops *ops)
kfree(nb);
return err;
}
return bus_for_each_dev(bus, NULL, &cb, add_iommu_group);
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 */
return iommu_bus_init(bus, ops);
err = iommu_bus_init(bus, ops);
if (err)
bus->iommu_ops = NULL;
return err;
}
EXPORT_SYMBOL_GPL(bus_set_iommu);