[PATCH RFC v1 02/11] iommu/virtio: Maintain a list of endpoints served by viommu_dev

[Vivek Gautam]

Keeping a record of list of endpoints that are served by the virtio-iommu
device would help in redirecting the requests of page faults to the
correct endpoint device to handle such requests.

Signed-off-by: Vivek Gautam <vivek.gautam at arm.com>
---
 drivers/iommu/virtio-iommu.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 50039070e2aa..c970f386f031 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -48,6 +48,7 @@ struct viommu_dev {
 	spinlock_t			request_lock;
 	struct list_head		requests;
 	void				*evts;
+	struct list_head		endpoints;
 
 	/* Device configuration */
 	struct iommu_domain_geometry	geometry;
@@ -115,6 +116,12 @@ struct viommu_endpoint {
 	void				*pgtf;
 };
 
+struct viommu_ep_entry {
+	u32				eid;
+	struct viommu_endpoint		*vdev;
+	struct list_head		list;
+};
+
 struct viommu_request {
 	struct list_head		list;
 	void				*writeback;
@@ -573,6 +580,7 @@ static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev)
 	size_t probe_len;
 	struct virtio_iommu_req_probe *probe;
 	struct virtio_iommu_probe_property *prop;
+	struct viommu_ep_entry *ep;
 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
 
@@ -640,6 +648,18 @@ static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev)
 		prop = (void *)probe->properties + cur;
 		type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK;
 	}
+	if (ret)
+		goto out_free;
+
+	ep = kzalloc(sizeof(*ep), GFP_KERNEL);
+	if (!ep) {
+		ret = -ENOMEM;
+		goto out_free;
+	}
+	ep->eid = probe->endpoint;
+	ep->vdev = vdev;
+
+	list_add(&ep->list, &viommu->endpoints);
 
 out_free:
 	kfree(probe);
@@ -1649,6 +1669,7 @@ static int viommu_probe(struct virtio_device *vdev)
 	viommu->dev = dev;
 	viommu->vdev = vdev;
 	INIT_LIST_HEAD(&viommu->requests);
+	INIT_LIST_HEAD(&viommu->endpoints);
 
 	ret = viommu_init_vqs(viommu);
 	if (ret)
-- 
2.17.1