RDMA/uverbs: Store the specs_root in the struct ib_uverbs_device

The specs are required to operate the uverbs file, so they belong inside
the ib_uverbs_device, not inside the ib_device. The spec passed in the
ib_device is just a communication from the driver and should not be used
during runtime.

This also changes the lifetime of the spec memory to match the
ib_uverbs_device, however at this time the spec_root can still contain
driver pointers after disassociation, so it cannot be used if ib_dev is
NULL. This is preparation for another series.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

drivers/infiniband/core/rdma_core.c

@@ -52,10 +52,10 @@ int uverbs_ns_idx(u16 *id, unsigned int ns_count)
 	return ret;
 }
 
-const struct uverbs_object_spec *uverbs_get_object(const struct ib_device *ibdev,
+const struct uverbs_object_spec *uverbs_get_object(struct ib_uverbs_file *ufile,
 						   uint16_t object)
 {
-	const struct uverbs_root_spec *object_hash = ibdev->specs_root;
+	const struct uverbs_root_spec *object_hash = ufile->device->specs_root;
 	const struct uverbs_object_spec_hash *objects;
 	int ret = uverbs_ns_idx(&object, object_hash->num_buckets);
 

drivers/infiniband/core/rdma_core.h

@@ -44,7 +44,7 @@
 #include <linux/mutex.h>
 
 int uverbs_ns_idx(u16 *id, unsigned int ns_count);
-const struct uverbs_object_spec *uverbs_get_object(const struct ib_device *ibdev,
+const struct uverbs_object_spec *uverbs_get_object(struct ib_uverbs_file *ufile,
 						   uint16_t object);
 const struct uverbs_method_spec *uverbs_get_method(const struct uverbs_object_spec *object,
 						   uint16_t method);

drivers/infiniband/core/uverbs_ioctl.c

@@ -46,8 +46,7 @@ static bool uverbs_is_attr_cleared(const struct ib_uverbs_attr *uattr,
 			   0, uattr->len - len);
 }
 
-static int uverbs_process_attr(struct ib_device *ibdev,
-			       struct ib_ucontext *ucontext,
+static int uverbs_process_attr(struct ib_uverbs_file *ufile,
 			       const struct ib_uverbs_attr *uattr,
 			       u16 attr_id,
 			       const struct uverbs_attr_spec_hash *attr_spec_bucket,
@@ -145,17 +144,18 @@ static int uverbs_process_attr(struct ib_device *ibdev,
 		if (uattr->attr_data.reserved)
 			return -EINVAL;
 
-		if (uattr->len != 0 || !ucontext || uattr->data > INT_MAX)
+		if (uattr->len != 0 || !ufile->ucontext ||
+		    uattr->data > INT_MAX)
 			return -EINVAL;
 
 		o_attr = &e->obj_attr;
-		object = uverbs_get_object(ibdev, spec->obj.obj_type);
+		object = uverbs_get_object(ufile, spec->obj.obj_type);
 		if (!object)
 			return -EINVAL;
 
 		o_attr->uobject = uverbs_get_uobject_from_context(
 					object->type_attrs,
-					ucontext,
+					ufile->ucontext,
 					spec->obj.access,
 					(int)uattr->data);
 
@@ -230,8 +230,7 @@ static int uverbs_finalize_attrs(struct uverbs_attr_bundle *attrs_bundle,
 	return ret;
 }
 
-static int uverbs_uattrs_process(struct ib_device *ibdev,
-				 struct ib_ucontext *ucontext,
+static int uverbs_uattrs_process(struct ib_uverbs_file *ufile,
 				 const struct ib_uverbs_attr *uattrs,
 				 size_t num_uattrs,
 				 const struct uverbs_method_spec *method,
@@ -267,9 +266,9 @@ static int uverbs_uattrs_process(struct ib_device *ibdev,
 			num_given_buckets = ret + 1;
 
 		attr_spec_bucket = method->attr_buckets[ret];
-		ret = uverbs_process_attr(ibdev, ucontext, uattr, attr_id,
-					  attr_spec_bucket, &attr_bundle->hash[ret],
-					  uattr_ptr++);
+		ret = uverbs_process_attr(ufile, uattr, attr_id,
+					  attr_spec_bucket,
+					  &attr_bundle->hash[ret], uattr_ptr++);
 		if (ret) {
 			uverbs_finalize_attrs(attr_bundle,
 					      method->attr_buckets,
@@ -324,9 +323,8 @@ static int uverbs_handle_method(struct ib_uverbs_attr __user *uattr_ptr,
 	int finalize_ret;
 	int num_given_buckets;
 
-	num_given_buckets = uverbs_uattrs_process(ibdev, ufile->ucontext, uattrs,
-						  num_uattrs, method_spec,
-						  attr_bundle, uattr_ptr);
+	num_given_buckets = uverbs_uattrs_process(
+		ufile, uattrs, num_uattrs, method_spec, attr_bundle, uattr_ptr);
 	if (num_given_buckets <= 0)
 		return -EINVAL;
 
@@ -367,7 +365,7 @@ static long ib_uverbs_cmd_verbs(struct ib_device *ib_dev,
 	if (hdr->driver_id != ib_dev->driver_id)
 		return -EINVAL;
 
-	object_spec = uverbs_get_object(ib_dev, hdr->object_id);
+	object_spec = uverbs_get_object(file, hdr->object_id);
 	if (!object_spec)
 		return -EPROTONOSUPPORT;
 

drivers/infiniband/core/uverbs_main.c

@@ -161,6 +161,7 @@ static void ib_uverbs_release_dev(struct kobject *kobj)
 		container_of(kobj, struct ib_uverbs_device, kobj);
 
 	cleanup_srcu_struct(&dev->disassociate_srcu);
+	uverbs_free_spec_tree(dev->specs_root);
 	kfree(dev);
 }
 
@@ -1067,7 +1068,7 @@ static void ib_uverbs_add_one(struct ib_device *device)
 	if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
 		goto err_class;
 
-	if (!device->specs_root) {
+	if (!device->driver_specs_root) {
 		const struct uverbs_object_tree_def *default_root[] = {
 			uverbs_default_get_objects()};
 
@@ -1075,8 +1076,13 @@ static void ib_uverbs_add_one(struct ib_device *device)
 								default_root);
 		if (IS_ERR(uverbs_dev->specs_root))
 			goto err_class;
-
-		device->specs_root = uverbs_dev->specs_root;
+	} else {
+		uverbs_dev->specs_root = device->driver_specs_root;
+		/*
+		 * Take responsibility to free the specs allocated by the
+		 * driver.
+		 */
+		device->driver_specs_root = NULL;
 	}
 
 	ib_set_client_data(device, &uverbs_client, uverbs_dev);
@@ -1241,10 +1247,6 @@ static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
 		ib_uverbs_comp_dev(uverbs_dev);
 	if (wait_clients)
 		wait_for_completion(&uverbs_dev->comp);
-	if (uverbs_dev->specs_root) {
-		uverbs_free_spec_tree(uverbs_dev->specs_root);
-		device->specs_root = NULL;
-	}
 
 	kobject_put(&uverbs_dev->kobj);
 }

drivers/infiniband/hw/mlx5/main.c

@@ -5350,15 +5350,15 @@ static int populate_specs_root(struct mlx5_ib_dev *dev)
 	    !WARN_ON(num_trees >= ARRAY_SIZE(default_root)))
 		default_root[num_trees++] = mlx5_ib_get_devx_tree();
 
-	dev->ib_dev.specs_root =
+	dev->ib_dev.driver_specs_root =
 		uverbs_alloc_spec_tree(num_trees, default_root);
 
-	return PTR_ERR_OR_ZERO(dev->ib_dev.specs_root);
+	return PTR_ERR_OR_ZERO(dev->ib_dev.driver_specs_root);
 }
 
 static void depopulate_specs_root(struct mlx5_ib_dev *dev)
 {
-	uverbs_free_spec_tree(dev->ib_dev.specs_root);
+	uverbs_free_spec_tree(dev->ib_dev.driver_specs_root);
 }
 
 static int mlx5_ib_read_counters(struct ib_counters *counters,

include/rdma/ib_verbs.h

@@ -2602,7 +2602,7 @@ struct ib_device {
 	const struct cpumask *(*get_vector_affinity)(struct ib_device *ibdev,
 						     int comp_vector);
 
-	struct uverbs_root_spec		*specs_root;
+	struct uverbs_root_spec		*driver_specs_root;
 	enum rdma_driver_id		driver_id;
 };