|  | // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB | 
|  | /* | 
|  | * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved. | 
|  | */ | 
|  | #include <rdma/uverbs_ioctl.h> | 
|  | #include <rdma/rdma_user_ioctl.h> | 
|  | #include <linux/bitops.h> | 
|  | #include "rdma_core.h" | 
|  | #include "uverbs.h" | 
|  |  | 
|  | static void *uapi_add_elm(struct uverbs_api *uapi, u32 key, size_t alloc_size) | 
|  | { | 
|  | void *elm; | 
|  | int rc; | 
|  |  | 
|  | if (key == UVERBS_API_KEY_ERR) | 
|  | return ERR_PTR(-EOVERFLOW); | 
|  |  | 
|  | elm = kzalloc(alloc_size, GFP_KERNEL); | 
|  | if (!elm) | 
|  | return ERR_PTR(-ENOMEM); | 
|  | rc = radix_tree_insert(&uapi->radix, key, elm); | 
|  | if (rc) { | 
|  | kfree(elm); | 
|  | return ERR_PTR(rc); | 
|  | } | 
|  |  | 
|  | return elm; | 
|  | } | 
|  |  | 
|  | static int uapi_merge_method(struct uverbs_api *uapi, | 
|  | struct uverbs_api_object *obj_elm, u32 obj_key, | 
|  | const struct uverbs_method_def *method, | 
|  | bool is_driver) | 
|  | { | 
|  | u32 method_key = obj_key | uapi_key_ioctl_method(method->id); | 
|  | struct uverbs_api_ioctl_method *method_elm; | 
|  | unsigned int i; | 
|  |  | 
|  | if (!method->attrs) | 
|  | return 0; | 
|  |  | 
|  | method_elm = uapi_add_elm(uapi, method_key, sizeof(*method_elm)); | 
|  | if (IS_ERR(method_elm)) { | 
|  | if (method_elm != ERR_PTR(-EEXIST)) | 
|  | return PTR_ERR(method_elm); | 
|  |  | 
|  | /* | 
|  | * This occurs when a driver uses ADD_UVERBS_ATTRIBUTES_SIMPLE | 
|  | */ | 
|  | if (WARN_ON(method->handler)) | 
|  | return -EINVAL; | 
|  | method_elm = radix_tree_lookup(&uapi->radix, method_key); | 
|  | if (WARN_ON(!method_elm)) | 
|  | return -EINVAL; | 
|  | } else { | 
|  | WARN_ON(!method->handler); | 
|  | rcu_assign_pointer(method_elm->handler, method->handler); | 
|  | if (method->handler != uverbs_destroy_def_handler) | 
|  | method_elm->driver_method = is_driver; | 
|  | } | 
|  |  | 
|  | for (i = 0; i != method->num_attrs; i++) { | 
|  | const struct uverbs_attr_def *attr = (*method->attrs)[i]; | 
|  | struct uverbs_api_attr *attr_slot; | 
|  |  | 
|  | if (!attr) | 
|  | continue; | 
|  |  | 
|  | /* | 
|  | * ENUM_IN contains the 'ids' pointer to the driver's .rodata, | 
|  | * so if it is specified by a driver then it always makes this | 
|  | * into a driver method. | 
|  | */ | 
|  | if (attr->attr.type == UVERBS_ATTR_TYPE_ENUM_IN) | 
|  | method_elm->driver_method |= is_driver; | 
|  |  | 
|  | attr_slot = | 
|  | uapi_add_elm(uapi, method_key | uapi_key_attr(attr->id), | 
|  | sizeof(*attr_slot)); | 
|  | /* Attributes are not allowed to be modified by drivers */ | 
|  | if (IS_ERR(attr_slot)) | 
|  | return PTR_ERR(attr_slot); | 
|  |  | 
|  | attr_slot->spec = attr->attr; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int uapi_merge_tree(struct uverbs_api *uapi, | 
|  | const struct uverbs_object_tree_def *tree, | 
|  | bool is_driver) | 
|  | { | 
|  | unsigned int i, j; | 
|  | int rc; | 
|  |  | 
|  | if (!tree->objects) | 
|  | return 0; | 
|  |  | 
|  | for (i = 0; i != tree->num_objects; i++) { | 
|  | const struct uverbs_object_def *obj = (*tree->objects)[i]; | 
|  | struct uverbs_api_object *obj_elm; | 
|  | u32 obj_key; | 
|  |  | 
|  | if (!obj) | 
|  | continue; | 
|  |  | 
|  | obj_key = uapi_key_obj(obj->id); | 
|  | obj_elm = uapi_add_elm(uapi, obj_key, sizeof(*obj_elm)); | 
|  | if (IS_ERR(obj_elm)) { | 
|  | if (obj_elm != ERR_PTR(-EEXIST)) | 
|  | return PTR_ERR(obj_elm); | 
|  |  | 
|  | /* This occurs when a driver uses ADD_UVERBS_METHODS */ | 
|  | if (WARN_ON(obj->type_attrs)) | 
|  | return -EINVAL; | 
|  | obj_elm = radix_tree_lookup(&uapi->radix, obj_key); | 
|  | if (WARN_ON(!obj_elm)) | 
|  | return -EINVAL; | 
|  | } else { | 
|  | obj_elm->type_attrs = obj->type_attrs; | 
|  | if (obj->type_attrs) { | 
|  | obj_elm->type_class = | 
|  | obj->type_attrs->type_class; | 
|  | /* | 
|  | * Today drivers are only permitted to use | 
|  | * idr_class types. They cannot use FD types | 
|  | * because we currently have no way to revoke | 
|  | * the fops pointer after device | 
|  | * disassociation. | 
|  | */ | 
|  | if (WARN_ON(is_driver && | 
|  | obj->type_attrs->type_class != | 
|  | &uverbs_idr_class)) | 
|  | return -EINVAL; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!obj->methods) | 
|  | continue; | 
|  |  | 
|  | for (j = 0; j != obj->num_methods; j++) { | 
|  | const struct uverbs_method_def *method = | 
|  | (*obj->methods)[j]; | 
|  | if (!method) | 
|  | continue; | 
|  |  | 
|  | rc = uapi_merge_method(uapi, obj_elm, obj_key, method, | 
|  | is_driver); | 
|  | if (rc) | 
|  | return rc; | 
|  | } | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int | 
|  | uapi_finalize_ioctl_method(struct uverbs_api *uapi, | 
|  | struct uverbs_api_ioctl_method *method_elm, | 
|  | u32 method_key) | 
|  | { | 
|  | struct radix_tree_iter iter; | 
|  | unsigned int num_attrs = 0; | 
|  | unsigned int max_bkey = 0; | 
|  | bool single_uobj = false; | 
|  | void __rcu **slot; | 
|  |  | 
|  | method_elm->destroy_bkey = UVERBS_API_ATTR_BKEY_LEN; | 
|  | radix_tree_for_each_slot (slot, &uapi->radix, &iter, | 
|  | uapi_key_attrs_start(method_key)) { | 
|  | struct uverbs_api_attr *elm = | 
|  | rcu_dereference_protected(*slot, true); | 
|  | u32 attr_key = iter.index & UVERBS_API_ATTR_KEY_MASK; | 
|  | u32 attr_bkey = uapi_bkey_attr(attr_key); | 
|  | u8 type = elm->spec.type; | 
|  |  | 
|  | if (uapi_key_attr_to_method(iter.index) != | 
|  | uapi_key_attr_to_method(method_key)) | 
|  | break; | 
|  |  | 
|  | if (elm->spec.mandatory) | 
|  | __set_bit(attr_bkey, method_elm->attr_mandatory); | 
|  |  | 
|  | if (type == UVERBS_ATTR_TYPE_IDR || | 
|  | type == UVERBS_ATTR_TYPE_FD) { | 
|  | u8 access = elm->spec.u.obj.access; | 
|  |  | 
|  | /* | 
|  | * Verbs specs may only have one NEW/DESTROY, we don't | 
|  | * have the infrastructure to abort multiple NEW's or | 
|  | * cope with multiple DESTROY failure. | 
|  | */ | 
|  | if (access == UVERBS_ACCESS_NEW || | 
|  | access == UVERBS_ACCESS_DESTROY) { | 
|  | if (WARN_ON(single_uobj)) | 
|  | return -EINVAL; | 
|  |  | 
|  | single_uobj = true; | 
|  | if (WARN_ON(!elm->spec.mandatory)) | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | if (access == UVERBS_ACCESS_DESTROY) | 
|  | method_elm->destroy_bkey = attr_bkey; | 
|  | } | 
|  |  | 
|  | max_bkey = max(max_bkey, attr_bkey); | 
|  | num_attrs++; | 
|  | } | 
|  |  | 
|  | method_elm->key_bitmap_len = max_bkey + 1; | 
|  | WARN_ON(method_elm->key_bitmap_len > UVERBS_API_ATTR_BKEY_LEN); | 
|  |  | 
|  | uapi_compute_bundle_size(method_elm, num_attrs); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int uapi_finalize(struct uverbs_api *uapi) | 
|  | { | 
|  | struct radix_tree_iter iter; | 
|  | void __rcu **slot; | 
|  | int rc; | 
|  |  | 
|  | radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) { | 
|  | struct uverbs_api_ioctl_method *method_elm = | 
|  | rcu_dereference_protected(*slot, true); | 
|  |  | 
|  | if (uapi_key_is_ioctl_method(iter.index)) { | 
|  | rc = uapi_finalize_ioctl_method(uapi, method_elm, | 
|  | iter.index); | 
|  | if (rc) | 
|  | return rc; | 
|  | } | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | void uverbs_destroy_api(struct uverbs_api *uapi) | 
|  | { | 
|  | struct radix_tree_iter iter; | 
|  | void __rcu **slot; | 
|  |  | 
|  | if (!uapi) | 
|  | return; | 
|  |  | 
|  | radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) { | 
|  | kfree(rcu_dereference_protected(*slot, true)); | 
|  | radix_tree_iter_delete(&uapi->radix, &iter, slot); | 
|  | } | 
|  | kfree(uapi); | 
|  | } | 
|  |  | 
|  | struct uverbs_api *uverbs_alloc_api( | 
|  | const struct uverbs_object_tree_def *const *driver_specs, | 
|  | enum rdma_driver_id driver_id) | 
|  | { | 
|  | struct uverbs_api *uapi; | 
|  | int rc; | 
|  |  | 
|  | uapi = kzalloc(sizeof(*uapi), GFP_KERNEL); | 
|  | if (!uapi) | 
|  | return ERR_PTR(-ENOMEM); | 
|  |  | 
|  | INIT_RADIX_TREE(&uapi->radix, GFP_KERNEL); | 
|  | uapi->driver_id = driver_id; | 
|  |  | 
|  | rc = uapi_merge_tree(uapi, uverbs_default_get_objects(), false); | 
|  | if (rc) | 
|  | goto err; | 
|  |  | 
|  | for (; driver_specs && *driver_specs; driver_specs++) { | 
|  | rc = uapi_merge_tree(uapi, *driver_specs, true); | 
|  | if (rc) | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | rc = uapi_finalize(uapi); | 
|  | if (rc) | 
|  | goto err; | 
|  |  | 
|  | return uapi; | 
|  | err: | 
|  | if (rc != -ENOMEM) | 
|  | pr_err("Setup of uverbs_api failed, kernel parsing tree description is not valid (%d)??\n", | 
|  | rc); | 
|  |  | 
|  | uverbs_destroy_api(uapi); | 
|  | return ERR_PTR(rc); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * The pre version is done before destroying the HW objects, it only blocks | 
|  | * off method access. All methods that require the ib_dev or the module data | 
|  | * must test one of these assignments prior to continuing. | 
|  | */ | 
|  | void uverbs_disassociate_api_pre(struct ib_uverbs_device *uverbs_dev) | 
|  | { | 
|  | struct uverbs_api *uapi = uverbs_dev->uapi; | 
|  | struct radix_tree_iter iter; | 
|  | void __rcu **slot; | 
|  |  | 
|  | rcu_assign_pointer(uverbs_dev->ib_dev, NULL); | 
|  |  | 
|  | radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) { | 
|  | if (uapi_key_is_ioctl_method(iter.index)) { | 
|  | struct uverbs_api_ioctl_method *method_elm = | 
|  | rcu_dereference_protected(*slot, true); | 
|  |  | 
|  | if (method_elm->driver_method) | 
|  | rcu_assign_pointer(method_elm->handler, NULL); | 
|  | } | 
|  | } | 
|  |  | 
|  | synchronize_srcu(&uverbs_dev->disassociate_srcu); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Called when a driver disassociates from the ib_uverbs_device. The | 
|  | * assumption is that the driver module will unload after. Replace everything | 
|  | * related to the driver with NULL as a safety measure. | 
|  | */ | 
|  | void uverbs_disassociate_api(struct uverbs_api *uapi) | 
|  | { | 
|  | struct radix_tree_iter iter; | 
|  | void __rcu **slot; | 
|  |  | 
|  | radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) { | 
|  | if (uapi_key_is_object(iter.index)) { | 
|  | struct uverbs_api_object *object_elm = | 
|  | rcu_dereference_protected(*slot, true); | 
|  |  | 
|  | /* | 
|  | * Some type_attrs are in the driver module. We don't | 
|  | * bother to keep track of which since there should be | 
|  | * no use of this after disassociate. | 
|  | */ | 
|  | object_elm->type_attrs = NULL; | 
|  | } else if (uapi_key_is_attr(iter.index)) { | 
|  | struct uverbs_api_attr *elm = | 
|  | rcu_dereference_protected(*slot, true); | 
|  |  | 
|  | if (elm->spec.type == UVERBS_ATTR_TYPE_ENUM_IN) | 
|  | elm->spec.u2.enum_def.ids = NULL; | 
|  | } | 
|  | } | 
|  | } |