Move the bus setup to iommu_device_register(). This should allow bus_iommu_probe() to be correctly replayed for multiple IOMMU instances, and leaves bus_set_iommu() as a glorfied no-op to be cleaned up next.
Note that although the handling of errors from bus_iommu_probe() looks inadequate, it is merely preserving the well-established existing behaviour. This could be improved in future - probably combined with equivalent cleanup for iommu_device_unregister() - but that isn't a priority right now. Signed-off-by: Robin Murphy <[email protected]> --- drivers/iommu/iommu.c | 50 ++++++++++++++++++++++--------------------- 1 file changed, 26 insertions(+), 24 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 13e1a8bd5435..51205c33c426 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -175,6 +175,14 @@ static int __init iommu_subsys_init(void) } subsys_initcall(iommu_subsys_init); +static int remove_iommu_group(struct device *dev, void *data) +{ + if (dev->iommu && dev->iommu->iommu_dev == data) + iommu_release_device(dev); + + return 0; +} + /** * iommu_device_register() - Register an IOMMU hardware instance * @iommu: IOMMU handle for the instance @@ -197,6 +205,22 @@ int iommu_device_register(struct iommu_device *iommu, spin_lock(&iommu_device_lock); list_add_tail(&iommu->list, &iommu_device_list); spin_unlock(&iommu_device_lock); + + for (int i = 0; i < ARRAY_SIZE(iommu_buses); i++) { + struct bus_type *bus = iommu_buses[i]; + const struct iommu_ops *bus_ops = bus->iommu_ops; + int err; + + WARN_ON(bus_ops && bus_ops != ops); + bus->iommu_ops = ops; + err = bus_iommu_probe(bus); + if (err) { + bus_for_each_dev(bus, NULL, iommu, remove_iommu_group); + bus->iommu_ops = bus_ops; + return err; + } + } + return 0; } EXPORT_SYMBOL_GPL(iommu_device_register); @@ -1654,13 +1678,6 @@ static int probe_iommu_group(struct device *dev, void *data) return ret; } -static int remove_iommu_group(struct device *dev, void *data) -{ - iommu_release_device(dev); - - return 0; -} - static int iommu_bus_notifier(struct notifier_block *nb, unsigned long action, void *data) { @@ -1883,27 +1900,12 @@ static int iommu_bus_init(struct bus_type *bus) */ int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops) { - int err; - - if (ops == NULL) { - bus->iommu_ops = NULL; - return 0; - } - - if (bus->iommu_ops != NULL) + if (bus->iommu_ops && ops && bus->iommu_ops != ops) return -EBUSY; bus->iommu_ops = ops; - /* Do IOMMU specific setup for this bus-type */ - err = bus_iommu_probe(bus); - if (err) { - /* Clean up */ - bus_for_each_dev(bus, NULL, NULL, remove_iommu_group); - bus->iommu_ops = NULL; - } - - return err; + return 0; } EXPORT_SYMBOL_GPL(bus_set_iommu); -- 2.28.0.dirty _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
