drm/lease: refactor lease idr setup and add some validationdrm-lease-v5

This is fairly simple validation, it verifies we hvae at least
one crtc/connector/plane in the lease.

(this could be relaxed later)

1 files changed, 134 insertions, 72 deletions

diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c
index 825bd6289c2a..4299513007fc 100644
--- a/drivers/gpu/drm/drm_lease.c
+++ b/drivers/gpu/drm/drm_lease.c
@@ -340,6 +340,128 @@ void _drm_lease_revoke(struct drm_master *top)
 	}
 }
 
+static int validate_lease(struct drm_device *dev,
+			  struct drm_file *lessor_priv,
+			  int object_count,
+			  struct drm_mode_object **objects)
+{
+	int o;
+	int has_crtc = -1;
+	int has_connector = -1;
+	int has_plane = -1;
+
+	/* we want to confirm that there is at least one crtc, plane
+	   connector object. */
+
+	for (o = 0; o < object_count; o++) {
+		if (objects[o]->type == DRM_MODE_OBJECT_CRTC && has_crtc == -1) {
+			has_crtc = o;
+		}
+		if (objects[o]->type == DRM_MODE_OBJECT_CONNECTOR && has_connector == -1)
+			has_connector = o;
+
+		if (lessor_priv->universal_planes) {
+			if (objects[o]->type == DRM_MODE_OBJECT_PLANE && has_plane == -1)
+				has_plane = o;
+		}
+	}
+	if (has_crtc == -1 || has_connector == -1)
+		return -EINVAL;
+	if (lessor_priv->universal_planes && has_plane == -1)
+		return -EINVAL;
+	return 0;
+}
+
+static int fill_object_idr(struct drm_device *dev,
+			   struct drm_file *lessor_priv,
+			   struct idr *leases,
+			   int object_count,
+			   u32 *object_ids)
+{
+	struct drm_mode_object **objects;
+	u32 o;
+	int ret;
+	objects = kcalloc(object_count, sizeof(struct drm_mode_object *),
+			  GFP_KERNEL);
+	if (!objects)
+		return -ENOMEM;
+
+	/* step one - get references to all the mode objects
+	   and check for validity. */
+	for (o = 0; o < object_count; o++) {
+		if ((int) object_ids[o] < 0) {
+			ret = -EINVAL;
+			goto out_free_objects;
+		}
+
+		objects[o] = drm_mode_object_find(dev, lessor_priv,
+						  object_ids[o],
+						  DRM_MODE_OBJECT_ANY);
+		if (!objects[o]) {
+			ret = -ENOENT;
+			goto out_free_objects;
+		}
+
+		if (!drm_mode_object_lease_required(objects[o]->type)) {
+			ret = -EINVAL;
+			goto out_free_objects;
+		}
+	}
+
+	ret = validate_lease(dev, lessor_priv, object_count, objects);
+	if (ret)
+		goto out_free_objects;
+
+	/* add their IDs to the lease request - taking into account
+	   universal planes */
+	for (o = 0; o < object_count; o++) {
+		struct drm_mode_object *obj = objects[o];
+		u32 object_id = objects[o]->id;
+		DRM_DEBUG_LEASE("Adding object %d to lease\n", object_id);
+
+		/*
+		 * We're using an IDR to hold the set of leased
+		 * objects, but we don't need to point at the object's
+		 * data structure from the lease as the main crtc_idr
+		 * will be used to actually find that. Instead, all we
+		 * really want is a 'leased/not-leased' result, for
+		 * which any non-NULL pointer will work fine.
+		 */
+		ret = idr_alloc(leases, &drm_lease_idr_object , object_id, object_id + 1, GFP_KERNEL);
+		if (ret < 0) {
+			DRM_DEBUG_LEASE("Object %d cannot be inserted into leases (%d)\n",
+					object_id, ret);
+			goto out_free_objects;
+		}
+		if (obj->type == DRM_MODE_OBJECT_CRTC && !lessor_priv->universal_planes) {
+			struct drm_crtc *crtc = obj_to_crtc(obj);
+			ret = idr_alloc(leases, &drm_lease_idr_object, crtc->primary->base.id, crtc->primary->base.id + 1, GFP_KERNEL);
+			if (ret < 0) {
+				DRM_DEBUG_LEASE("Object primary plane %d cannot be inserted into leases (%d)\n",
+						object_id, ret);
+				goto out_free_objects;
+			}
+			if (crtc->cursor) {
+				ret = idr_alloc(leases, &drm_lease_idr_object, crtc->cursor->base.id, crtc->cursor->base.id + 1, GFP_KERNEL);
+				if (ret < 0) {
+					DRM_DEBUG_LEASE("Object cursor plane %d cannot be inserted into leases (%d)\n",
+							object_id, ret);
+					goto out_free_objects;
+				}
+			}
+		}
+	}
+
+	ret = 0;
+out_free_objects:
+	for (o = 0; o < object_count; o++) {
+		if (objects[o])
+			drm_mode_object_put(objects[o]);
+	}
+	kfree(objects);
+	return ret;
+}
+
 /**
  * drm_mode_create_lease_ioctl - create a new lease
  * @dev: the drm device
@@ -356,7 +478,6 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev,
 {
 	struct drm_mode_create_lease *cl = data;
 	size_t object_count;
-	size_t o;
 	int ret = 0;
 	struct idr leases;
 	struct drm_master *lessor = lessor_priv->master;
@@ -386,81 +507,22 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev,
 
 	idr_init(&leases);
 
+	/* fill and validate the object idr */
+	ret = fill_object_idr(dev, lessor_priv, &leases,
+			      object_count, object_ids);
+	kfree(object_ids);
+	if (ret) {
+		idr_destroy(&leases);
+		return ret;
+	}
+
 	/* Allocate a file descriptor for the lease */
 	fd = get_unused_fd_flags(cl->flags & (O_CLOEXEC | O_NONBLOCK));
 	if (fd < 0) {
-		kfree(object_ids);
+		idr_destroy(&leases);
 		return fd;
 	}
 
-	DRM_DEBUG_LEASE("Creating new lease\n");
-
-	/* Lookup the mode objects and add their IDs to the lease request */
-	for (o = 0; o < object_count; o++) {
-		__u32 object_id = object_ids[o];
-		struct drm_mode_object *obj;
-
-		DRM_DEBUG_LEASE("Adding object %d to lease\n", object_id);
-
-		if ((int) object_id < 0) {
-			ret = -EINVAL;
-			goto out_leases;
-		}
-
-		obj = drm_mode_object_find(dev, lessor_priv, object_id,
-					   DRM_MODE_OBJECT_ANY);
-		if (!obj) {
-			ret = -ENOENT;
-			goto out_leases;
-		}
-
-		/* only allow leasing on crtc/plane/connector objects */
-		if (!drm_mode_object_lease_required(obj->type)) {
-			ret = -EINVAL;
-			drm_mode_object_put(obj);
-			goto out_leases;
-		}
-
-		/*
-		 * We're using an IDR to hold the set of leased
-		 * objects, but we don't need to point at the object's
-		 * data structure from the lease as the main crtc_idr
-		 * will be used to actually find that. Instead, all we
-		 * really want is a 'leased/not-leased' result, for
-		 * which any non-NULL pointer will work fine.
-		 */
-		ret = idr_alloc(&leases, &drm_lease_idr_object , object_id, object_id + 1, GFP_KERNEL);
-		if (ret < 0) {
-			DRM_DEBUG_LEASE("Object %d cannot be inserted into leases (%d)\n",
-					object_id, ret);
-			drm_mode_object_put(obj);
-			goto out_leases;
-		}
-		if (obj->type == DRM_MODE_OBJECT_CRTC && !lessor_priv->universal_planes) {
-			struct drm_crtc *crtc = obj_to_crtc(obj);
-			ret = idr_alloc(&leases, &drm_lease_idr_object, crtc->primary->base.id, crtc->primary->base.id + 1, GFP_KERNEL);
-			if (ret < 0) {
-				DRM_DEBUG_LEASE("Object primary plane %d cannot be inserted into leases (%d)\n",
-						object_id, ret);
-				drm_mode_object_put(obj);
-				goto out_leases;
-			}
-			if (crtc->cursor) {
-				ret = idr_alloc(&leases, &drm_lease_idr_object, crtc->cursor->base.id, crtc->cursor->base.id + 1, GFP_KERNEL);
-				if (ret < 0) {
-					DRM_DEBUG_LEASE("Object cursor plane %d cannot be inserted into leases (%d)\n",
-							object_id, ret);
-					drm_mode_object_put(obj);
-					goto out_leases;
-				}
-			}
-		}
-		drm_mode_object_put(obj);
-	}
-
-	kfree(object_ids);
-	object_ids = NULL;
-
 	mutex_lock(&dev->master_mutex);
 
 	DRM_DEBUG_LEASE("Creating lease\n");
@@ -517,9 +579,9 @@ out_lessee:
 	drm_master_put(&lessee);
 
 out_leases:
-	idr_destroy(&leases);
 	put_unused_fd(fd);
-	kfree(object_ids);
+	idr_destroy(&leases);
+
 	DRM_DEBUG_LEASE("drm_mode_create_lease_ioctl failed: %d\n", ret);
 	return ret;
 }