Much like arm-smmu in commit 7d835134d4e1 ("iommu/arm-smmu: Make
instance lookup robust"), virtio-iommu appears to have the same issue
where iommu_device_register() makes the IOMMU instance visible to other
API callers (including itself) straight away, but internally the
instance isn't ready to recognise itself for viommu_probe_device() to
work correctly until after viommu_probe() has returned. This matters a
lot more now that bus_iommu_probe() has the DT/VIOT knowledge to probe
client devices the way that was always intended. Tweak the lookup and
initialisation in much the same way as for arm-smmu, to ensure that what
we register is functional and ready to go.
Fixes: bcb81ac6ae3c ("iommu: Get DT/ACPI parsing into the proper probe path")
Signed-off-by: Robin Murphy <[email protected]>
---
Pre-emptive fix by inspection...
---
drivers/iommu/virtio-iommu.c | 20 ++++++++------------
1 file changed, 8 insertions(+), 12 deletions(-)
diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index b85ce6310ddb..6cc8f33bdc18 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -972,18 +972,11 @@ static void viommu_get_resv_regions(struct device *dev,
struct list_head *head)
iommu_dma_get_resv_regions(dev, head);
}
-static struct iommu_ops viommu_ops;
-static struct virtio_driver virtio_iommu_drv;
-
-static int viommu_match_node(struct device *dev, const void *data)
-{
- return device_match_fwnode(dev->parent, data);
-}
-
+static const struct bus_type *virtio_bus_type;
static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode)
{
- struct device *dev = driver_find_device(&virtio_iommu_drv.driver, NULL,
- fwnode, viommu_match_node);
+ struct device *dev = bus_find_device_by_fwnode(virtio_bus_type, fwnode);
+
put_device(dev);
return dev ? dev_to_virtio(dev)->priv : NULL;
@@ -1133,6 +1126,9 @@ static int viommu_probe(struct virtio_device *vdev)
if (!viommu)
return -ENOMEM;
+ /* Borrow this for easy lookups later */
+ virtio_bus_type = dev->bus;
+
spin_lock_init(&viommu->request_lock);
ida_init(&viommu->domain_ids);
viommu->dev = dev;
@@ -1198,10 +1194,10 @@ static int viommu_probe(struct virtio_device *vdev)
if (ret)
goto err_free_vqs;
- iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev);
-
vdev->priv = viommu;
+ iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev);
+
dev_info(dev, "input address: %u bits\n",
order_base_2(viommu->geometry.aperture_end));
dev_info(dev, "page mask: %#llx\n", viommu->pgsize_bitmap);
--
2.39.2.101.g768bb238c484.dirty
