[PATCH 2/9] vfio/fsl-mc: Scan DPRC objects on vfio-fsl-mc driver bind

[Diana Craciun <diana.craciun@xxxxxxxxxxx>]

The DPRC (Data Path Resource Container) device is a bus device and has
child devices attached to it. When the vfio-fsl-mc driver is probed
the DPRC is scanned and the child devices discovered and initialized.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@xxxxxxx>
Signed-off-by: Diana Craciun <diana.craciun@xxxxxxxxxxx>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c | 66 +++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 320fb09b5691..5cc533808bc1 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -74,6 +74,34 @@ static int vfio_fsl_mc_mmap(void *device_data, struct vm_area_struct *vma)
 	return -EINVAL;
 }
 
+static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	int ret = 0;
+
+	/* Non-dprc devices share mc_io from parent */
+	if (!is_fsl_mc_bus_dprc(mc_dev)) {
+		struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);
+
+		mc_dev->mc_io = mc_cont->mc_io;
+		return 0;
+	}
+
+	/* open DPRC, allocate a MC portal */
+	ret = dprc_setup(mc_dev);
+	if (ret < 0) {
+		dev_err(&mc_dev->dev, "Failed to setup DPRC (error = %d)\n", ret);
+		return ret;
+	}
+
+	ret = dprc_scan_container(mc_dev, mc_dev->driver_override, false);
+	if (ret < 0) {
+		dev_err(&mc_dev->dev, "Container scanning failed: %d\n", ret);
+		dprc_cleanup(mc_dev);
+	}
+
+	return 0;
+}
 static const struct vfio_device_ops vfio_fsl_mc_ops = {
 	.name		= "vfio-fsl-mc",
 	.open		= vfio_fsl_mc_open,
@@ -112,9 +140,42 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 		return ret;
 	}
 
+	ret = vfio_fsl_mc_init_device(vdev);
+	if (ret) {
+		vfio_iommu_group_put(group, dev);
+		return ret;
+	}
+
 	return ret;
 }
 
+static int vfio_fsl_mc_device_remove(struct device *dev, void *data)
+{
+	struct fsl_mc_device *mc_dev;
+
+	WARN_ON(!dev);
+	mc_dev = to_fsl_mc_device(dev);
+	if (WARN_ON(!mc_dev))
+		return -ENODEV;
+
+	kfree(mc_dev->driver_override);
+	mc_dev->driver_override = NULL;
+
+	/*
+	 * The device-specific remove callback will get invoked by device_del()
+	 */
+	device_del(&mc_dev->dev);
+	put_device(&mc_dev->dev);
+
+	return 0;
+}
+
+static void vfio_fsl_mc_cleanup_dprc(struct fsl_mc_device *mc_dev)
+{
+	device_for_each_child(&mc_dev->dev, NULL, vfio_fsl_mc_device_remove);
+	dprc_cleanup(mc_dev);
+}
+
 static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 {
 	struct vfio_fsl_mc_device *vdev;
@@ -124,6 +185,11 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 	if (!vdev)
 		return -EINVAL;
 
+	if (is_fsl_mc_bus_dprc(mc_dev))
+		vfio_fsl_mc_cleanup_dprc(vdev->mc_dev);
+
+	mc_dev->mc_io = NULL;
+
 	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
 	devm_kfree(dev, vdev);
 
-- 
2.17.1