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1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB2/*3 * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.4 */5#include <rdma/uverbs_ioctl.h>6#include <rdma/rdma_user_ioctl.h>7#include <linux/bitops.h>8#include "rdma_core.h"9#include "uverbs.h"10 11static int ib_uverbs_notsupp(struct uverbs_attr_bundle *attrs)12{13	return -EOPNOTSUPP;14}15 16static void *uapi_add_elm(struct uverbs_api *uapi, u32 key, size_t alloc_size)17{18	void *elm;19	int rc;20 21	if (key == UVERBS_API_KEY_ERR)22		return ERR_PTR(-EOVERFLOW);23 24	elm = kzalloc(alloc_size, GFP_KERNEL);25	if (!elm)26		return ERR_PTR(-ENOMEM);27	rc = radix_tree_insert(&uapi->radix, key, elm);28	if (rc) {29		kfree(elm);30		return ERR_PTR(rc);31	}32 33	return elm;34}35 36static void *uapi_add_get_elm(struct uverbs_api *uapi, u32 key,37			      size_t alloc_size, bool *exists)38{39	void *elm;40 41	elm = uapi_add_elm(uapi, key, alloc_size);42	if (!IS_ERR(elm)) {43		*exists = false;44		return elm;45	}46 47	if (elm != ERR_PTR(-EEXIST))48		return elm;49 50	elm = radix_tree_lookup(&uapi->radix, key);51	if (WARN_ON(!elm))52		return ERR_PTR(-EINVAL);53	*exists = true;54	return elm;55}56 57static int uapi_create_write(struct uverbs_api *uapi,58			     struct ib_device *ibdev,59			     const struct uapi_definition *def,60			     u32 obj_key,61			     u32 *cur_method_key)62{63	struct uverbs_api_write_method *method_elm;64	u32 method_key = obj_key;65	bool exists;66 67	if (def->write.is_ex)68		method_key |= uapi_key_write_ex_method(def->write.command_num);69	else70		method_key |= uapi_key_write_method(def->write.command_num);71 72	method_elm = uapi_add_get_elm(uapi, method_key, sizeof(*method_elm),73				      &exists);74	if (IS_ERR(method_elm))75		return PTR_ERR(method_elm);76 77	if (WARN_ON(exists && (def->write.is_ex != method_elm->is_ex)))78		return -EINVAL;79 80	method_elm->is_ex = def->write.is_ex;81	method_elm->handler = def->func_write;82	if (!def->write.is_ex)83		method_elm->disabled = !(ibdev->uverbs_cmd_mask &84					 BIT_ULL(def->write.command_num));85 86	if (!def->write.is_ex && def->func_write) {87		method_elm->has_udata = def->write.has_udata;88		method_elm->has_resp = def->write.has_resp;89		method_elm->req_size = def->write.req_size;90		method_elm->resp_size = def->write.resp_size;91	}92 93	*cur_method_key = method_key;94	return 0;95}96 97static int uapi_merge_method(struct uverbs_api *uapi,98			     struct uverbs_api_object *obj_elm, u32 obj_key,99			     const struct uverbs_method_def *method,100			     bool is_driver)101{102	u32 method_key = obj_key | uapi_key_ioctl_method(method->id);103	struct uverbs_api_ioctl_method *method_elm;104	unsigned int i;105	bool exists;106 107	if (!method->attrs)108		return 0;109 110	method_elm = uapi_add_get_elm(uapi, method_key, sizeof(*method_elm),111				      &exists);112	if (IS_ERR(method_elm))113		return PTR_ERR(method_elm);114	if (exists) {115		/*116		 * This occurs when a driver uses ADD_UVERBS_ATTRIBUTES_SIMPLE117		 */118		if (WARN_ON(method->handler))119			return -EINVAL;120	} else {121		WARN_ON(!method->handler);122		rcu_assign_pointer(method_elm->handler, method->handler);123		if (method->handler != uverbs_destroy_def_handler)124			method_elm->driver_method = is_driver;125	}126 127	for (i = 0; i != method->num_attrs; i++) {128		const struct uverbs_attr_def *attr = (*method->attrs)[i];129		struct uverbs_api_attr *attr_slot;130 131		if (!attr)132			continue;133 134		/*135		 * ENUM_IN contains the 'ids' pointer to the driver's .rodata,136		 * so if it is specified by a driver then it always makes this137		 * into a driver method.138		 */139		if (attr->attr.type == UVERBS_ATTR_TYPE_ENUM_IN)140			method_elm->driver_method |= is_driver;141 142		/*143		 * Like other uobject based things we only support a single144		 * uobject being NEW'd or DESTROY'd145		 */146		if (attr->attr.type == UVERBS_ATTR_TYPE_IDRS_ARRAY) {147			u8 access = attr->attr.u2.objs_arr.access;148 149			if (WARN_ON(access == UVERBS_ACCESS_NEW ||150				    access == UVERBS_ACCESS_DESTROY))151				return -EINVAL;152		}153 154		attr_slot =155			uapi_add_elm(uapi, method_key | uapi_key_attr(attr->id),156				     sizeof(*attr_slot));157		/* Attributes are not allowed to be modified by drivers */158		if (IS_ERR(attr_slot))159			return PTR_ERR(attr_slot);160 161		attr_slot->spec = attr->attr;162	}163 164	return 0;165}166 167static int uapi_merge_obj_tree(struct uverbs_api *uapi,168			       const struct uverbs_object_def *obj,169			       bool is_driver)170{171	struct uverbs_api_object *obj_elm;172	unsigned int i;173	u32 obj_key;174	bool exists;175	int rc;176 177	obj_key = uapi_key_obj(obj->id);178	obj_elm = uapi_add_get_elm(uapi, obj_key, sizeof(*obj_elm), &exists);179	if (IS_ERR(obj_elm))180		return PTR_ERR(obj_elm);181 182	if (obj->type_attrs) {183		if (WARN_ON(obj_elm->type_attrs))184			return -EINVAL;185 186		obj_elm->id = obj->id;187		obj_elm->type_attrs = obj->type_attrs;188		obj_elm->type_class = obj->type_attrs->type_class;189		/*190		 * Today drivers are only permitted to use idr_class and191		 * fd_class types. We can revoke the IDR types during192		 * disassociation, and the FD types require the driver to use193		 * struct file_operations.owner to prevent the driver module194		 * code from unloading while the file is open. This provides195		 * enough safety that uverbs_uobject_fd_release() will196		 * continue to work.  Drivers using FD are responsible to197		 * handle disassociation of the device on their own.198		 */199		if (WARN_ON(is_driver &&200			    obj->type_attrs->type_class != &uverbs_idr_class &&201			    obj->type_attrs->type_class != &uverbs_fd_class))202			return -EINVAL;203	}204 205	if (!obj->methods)206		return 0;207 208	for (i = 0; i != obj->num_methods; i++) {209		const struct uverbs_method_def *method = (*obj->methods)[i];210 211		if (!method)212			continue;213 214		rc = uapi_merge_method(uapi, obj_elm, obj_key, method,215				       is_driver);216		if (rc)217			return rc;218	}219 220	return 0;221}222 223static int uapi_disable_elm(struct uverbs_api *uapi,224			    const struct uapi_definition *def,225			    u32 obj_key,226			    u32 method_key)227{228	bool exists;229 230	if (def->scope == UAPI_SCOPE_OBJECT) {231		struct uverbs_api_object *obj_elm;232 233		obj_elm = uapi_add_get_elm(234			uapi, obj_key, sizeof(*obj_elm), &exists);235		if (IS_ERR(obj_elm))236			return PTR_ERR(obj_elm);237		obj_elm->disabled = 1;238		return 0;239	}240 241	if (def->scope == UAPI_SCOPE_METHOD &&242	    uapi_key_is_ioctl_method(method_key)) {243		struct uverbs_api_ioctl_method *method_elm;244 245		method_elm = uapi_add_get_elm(uapi, method_key,246					      sizeof(*method_elm), &exists);247		if (IS_ERR(method_elm))248			return PTR_ERR(method_elm);249		method_elm->disabled = 1;250		return 0;251	}252 253	if (def->scope == UAPI_SCOPE_METHOD &&254	    (uapi_key_is_write_method(method_key) ||255	     uapi_key_is_write_ex_method(method_key))) {256		struct uverbs_api_write_method *write_elm;257 258		write_elm = uapi_add_get_elm(uapi, method_key,259					     sizeof(*write_elm), &exists);260		if (IS_ERR(write_elm))261			return PTR_ERR(write_elm);262		write_elm->disabled = 1;263		return 0;264	}265 266	WARN_ON(true);267	return -EINVAL;268}269 270static int uapi_merge_def(struct uverbs_api *uapi, struct ib_device *ibdev,271			  const struct uapi_definition *def_list,272			  bool is_driver)273{274	const struct uapi_definition *def = def_list;275	u32 cur_obj_key = UVERBS_API_KEY_ERR;276	u32 cur_method_key = UVERBS_API_KEY_ERR;277	bool exists;278	int rc;279 280	if (!def_list)281		return 0;282 283	for (;; def++) {284		switch ((enum uapi_definition_kind)def->kind) {285		case UAPI_DEF_CHAIN:286			rc = uapi_merge_def(uapi, ibdev, def->chain, is_driver);287			if (rc)288				return rc;289			continue;290 291		case UAPI_DEF_CHAIN_OBJ_TREE:292			if (WARN_ON(def->object_start.object_id !=293				    def->chain_obj_tree->id))294				return -EINVAL;295 296			cur_obj_key = uapi_key_obj(def->object_start.object_id);297			rc = uapi_merge_obj_tree(uapi, def->chain_obj_tree,298						 is_driver);299			if (rc)300				return rc;301			continue;302 303		case UAPI_DEF_END:304			return 0;305 306		case UAPI_DEF_IS_SUPPORTED_DEV_FN: {307			void **ibdev_fn =308				(void *)(&ibdev->ops) + def->needs_fn_offset;309 310			if (*ibdev_fn)311				continue;312			rc = uapi_disable_elm(313				uapi, def, cur_obj_key, cur_method_key);314			if (rc)315				return rc;316			continue;317		}318 319		case UAPI_DEF_IS_SUPPORTED_FUNC:320			if (def->func_is_supported(ibdev))321				continue;322			rc = uapi_disable_elm(323				uapi, def, cur_obj_key, cur_method_key);324			if (rc)325				return rc;326			continue;327 328		case UAPI_DEF_OBJECT_START: {329			struct uverbs_api_object *obj_elm;330 331			cur_obj_key = uapi_key_obj(def->object_start.object_id);332			obj_elm = uapi_add_get_elm(uapi, cur_obj_key,333						   sizeof(*obj_elm), &exists);334			if (IS_ERR(obj_elm))335				return PTR_ERR(obj_elm);336			continue;337		}338 339		case UAPI_DEF_WRITE:340			rc = uapi_create_write(341				uapi, ibdev, def, cur_obj_key, &cur_method_key);342			if (rc)343				return rc;344			continue;345		}346		WARN_ON(true);347		return -EINVAL;348	}349}350 351static int352uapi_finalize_ioctl_method(struct uverbs_api *uapi,353			   struct uverbs_api_ioctl_method *method_elm,354			   u32 method_key)355{356	struct radix_tree_iter iter;357	unsigned int num_attrs = 0;358	unsigned int max_bkey = 0;359	bool single_uobj = false;360	void __rcu **slot;361 362	method_elm->destroy_bkey = UVERBS_API_ATTR_BKEY_LEN;363	radix_tree_for_each_slot (slot, &uapi->radix, &iter,364				  uapi_key_attrs_start(method_key)) {365		struct uverbs_api_attr *elm =366			rcu_dereference_protected(*slot, true);367		u32 attr_key = iter.index & UVERBS_API_ATTR_KEY_MASK;368		u32 attr_bkey = uapi_bkey_attr(attr_key);369		u8 type = elm->spec.type;370 371		if (uapi_key_attr_to_ioctl_method(iter.index) !=372		    uapi_key_attr_to_ioctl_method(method_key))373			break;374 375		if (elm->spec.mandatory)376			__set_bit(attr_bkey, method_elm->attr_mandatory);377 378		if (elm->spec.is_udata)379			method_elm->has_udata = true;380 381		if (type == UVERBS_ATTR_TYPE_IDR ||382		    type == UVERBS_ATTR_TYPE_FD) {383			u8 access = elm->spec.u.obj.access;384 385			/*386			 * Verbs specs may only have one NEW/DESTROY, we don't387			 * have the infrastructure to abort multiple NEW's or388			 * cope with multiple DESTROY failure.389			 */390			if (access == UVERBS_ACCESS_NEW ||391			    access == UVERBS_ACCESS_DESTROY) {392				if (WARN_ON(single_uobj))393					return -EINVAL;394 395				single_uobj = true;396				if (WARN_ON(!elm->spec.mandatory))397					return -EINVAL;398			}399 400			if (access == UVERBS_ACCESS_DESTROY)401				method_elm->destroy_bkey = attr_bkey;402		}403 404		max_bkey = max(max_bkey, attr_bkey);405		num_attrs++;406	}407 408	method_elm->key_bitmap_len = max_bkey + 1;409	WARN_ON(method_elm->key_bitmap_len > UVERBS_API_ATTR_BKEY_LEN);410 411	uapi_compute_bundle_size(method_elm, num_attrs);412	return 0;413}414 415static int uapi_finalize(struct uverbs_api *uapi)416{417	const struct uverbs_api_write_method **data;418	unsigned long max_write_ex = 0;419	unsigned long max_write = 0;420	struct radix_tree_iter iter;421	void __rcu **slot;422	int rc;423	int i;424 425	radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) {426		struct uverbs_api_ioctl_method *method_elm =427			rcu_dereference_protected(*slot, true);428 429		if (uapi_key_is_ioctl_method(iter.index)) {430			rc = uapi_finalize_ioctl_method(uapi, method_elm,431							iter.index);432			if (rc)433				return rc;434		}435 436		if (uapi_key_is_write_method(iter.index))437			max_write = max(max_write,438					iter.index & UVERBS_API_ATTR_KEY_MASK);439		if (uapi_key_is_write_ex_method(iter.index))440			max_write_ex =441				max(max_write_ex,442				    iter.index & UVERBS_API_ATTR_KEY_MASK);443	}444 445	uapi->notsupp_method.handler = ib_uverbs_notsupp;446	uapi->num_write = max_write + 1;447	uapi->num_write_ex = max_write_ex + 1;448	data = kmalloc_array(uapi->num_write + uapi->num_write_ex,449			     sizeof(*uapi->write_methods), GFP_KERNEL);450	if (!data)451		return -ENOMEM;452 453	for (i = 0; i != uapi->num_write + uapi->num_write_ex; i++)454		data[i] = &uapi->notsupp_method;455	uapi->write_methods = data;456	uapi->write_ex_methods = data + uapi->num_write;457 458	radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) {459		if (uapi_key_is_write_method(iter.index))460			uapi->write_methods[iter.index &461					    UVERBS_API_ATTR_KEY_MASK] =462				rcu_dereference_protected(*slot, true);463		if (uapi_key_is_write_ex_method(iter.index))464			uapi->write_ex_methods[iter.index &465					       UVERBS_API_ATTR_KEY_MASK] =466				rcu_dereference_protected(*slot, true);467	}468 469	return 0;470}471 472static void uapi_remove_range(struct uverbs_api *uapi, u32 start, u32 last)473{474	struct radix_tree_iter iter;475	void __rcu **slot;476 477	radix_tree_for_each_slot (slot, &uapi->radix, &iter, start) {478		if (iter.index > last)479			return;480		kfree(rcu_dereference_protected(*slot, true));481		radix_tree_iter_delete(&uapi->radix, &iter, slot);482	}483}484 485static void uapi_remove_object(struct uverbs_api *uapi, u32 obj_key)486{487	uapi_remove_range(uapi, obj_key,488			  obj_key | UVERBS_API_METHOD_KEY_MASK |489				  UVERBS_API_ATTR_KEY_MASK);490}491 492static void uapi_remove_method(struct uverbs_api *uapi, u32 method_key)493{494	uapi_remove_range(uapi, method_key,495			  method_key | UVERBS_API_ATTR_KEY_MASK);496}497 498 499static u32 uapi_get_obj_id(struct uverbs_attr_spec *spec)500{501	if (spec->type == UVERBS_ATTR_TYPE_IDR ||502	    spec->type == UVERBS_ATTR_TYPE_FD)503		return spec->u.obj.obj_type;504	if (spec->type == UVERBS_ATTR_TYPE_IDRS_ARRAY)505		return spec->u2.objs_arr.obj_type;506	return UVERBS_API_KEY_ERR;507}508 509static void uapi_key_okay(u32 key)510{511	unsigned int count = 0;512 513	if (uapi_key_is_object(key))514		count++;515	if (uapi_key_is_ioctl_method(key))516		count++;517	if (uapi_key_is_write_method(key))518		count++;519	if (uapi_key_is_write_ex_method(key))520		count++;521	if (uapi_key_is_attr(key))522		count++;523	WARN(count != 1, "Bad count %u key=%x", count, key);524}525 526static void uapi_finalize_disable(struct uverbs_api *uapi)527{528	struct radix_tree_iter iter;529	u32 starting_key = 0;530	bool scan_again = false;531	void __rcu **slot;532 533again:534	radix_tree_for_each_slot (slot, &uapi->radix, &iter, starting_key) {535		uapi_key_okay(iter.index);536 537		if (uapi_key_is_object(iter.index)) {538			struct uverbs_api_object *obj_elm =539				rcu_dereference_protected(*slot, true);540 541			if (obj_elm->disabled) {542				/* Have to check all the attrs again */543				scan_again = true;544				starting_key = iter.index;545				uapi_remove_object(uapi, iter.index);546				goto again;547			}548			continue;549		}550 551		if (uapi_key_is_ioctl_method(iter.index)) {552			struct uverbs_api_ioctl_method *method_elm =553				rcu_dereference_protected(*slot, true);554 555			if (method_elm->disabled) {556				starting_key = iter.index;557				uapi_remove_method(uapi, iter.index);558				goto again;559			}560			continue;561		}562 563		if (uapi_key_is_write_method(iter.index) ||564		    uapi_key_is_write_ex_method(iter.index)) {565			struct uverbs_api_write_method *method_elm =566				rcu_dereference_protected(*slot, true);567 568			if (method_elm->disabled) {569				kfree(method_elm);570				radix_tree_iter_delete(&uapi->radix, &iter, slot);571			}572			continue;573		}574 575		if (uapi_key_is_attr(iter.index)) {576			struct uverbs_api_attr *attr_elm =577				rcu_dereference_protected(*slot, true);578			const struct uverbs_api_object *tmp_obj;579			u32 obj_key;580 581			/*582			 * If the method has a mandatory object handle583			 * attribute which relies on an object which is not584			 * present then the entire method is uncallable.585			 */586			if (!attr_elm->spec.mandatory)587				continue;588			obj_key = uapi_get_obj_id(&attr_elm->spec);589			if (obj_key == UVERBS_API_KEY_ERR)590				continue;591			tmp_obj = uapi_get_object(uapi, obj_key);592			if (IS_ERR(tmp_obj)) {593				if (PTR_ERR(tmp_obj) == -ENOMSG)594					continue;595			} else {596				if (!tmp_obj->disabled)597					continue;598			}599 600			starting_key = iter.index;601			uapi_remove_method(602				uapi,603				iter.index & (UVERBS_API_OBJ_KEY_MASK |604					      UVERBS_API_METHOD_KEY_MASK));605			goto again;606		}607 608		WARN_ON(false);609	}610 611	if (!scan_again)612		return;613	scan_again = false;614	starting_key = 0;615	goto again;616}617 618void uverbs_destroy_api(struct uverbs_api *uapi)619{620	if (!uapi)621		return;622 623	uapi_remove_range(uapi, 0, U32_MAX);624	kfree(uapi->write_methods);625	kfree(uapi);626}627 628static const struct uapi_definition uverbs_core_api[] = {629	UAPI_DEF_CHAIN(uverbs_def_obj_async_fd),630	UAPI_DEF_CHAIN(uverbs_def_obj_counters),631	UAPI_DEF_CHAIN(uverbs_def_obj_cq),632	UAPI_DEF_CHAIN(uverbs_def_obj_device),633	UAPI_DEF_CHAIN(uverbs_def_obj_dm),634	UAPI_DEF_CHAIN(uverbs_def_obj_flow_action),635	UAPI_DEF_CHAIN(uverbs_def_obj_intf),636	UAPI_DEF_CHAIN(uverbs_def_obj_mr),637	UAPI_DEF_CHAIN(uverbs_def_obj_qp),638	UAPI_DEF_CHAIN(uverbs_def_obj_srq),639	UAPI_DEF_CHAIN(uverbs_def_obj_wq),640	UAPI_DEF_CHAIN(uverbs_def_write_intf),641	{},642};643 644struct uverbs_api *uverbs_alloc_api(struct ib_device *ibdev)645{646	struct uverbs_api *uapi;647	int rc;648 649	uapi = kzalloc(sizeof(*uapi), GFP_KERNEL);650	if (!uapi)651		return ERR_PTR(-ENOMEM);652 653	INIT_RADIX_TREE(&uapi->radix, GFP_KERNEL);654	uapi->driver_id = ibdev->ops.driver_id;655 656	rc = uapi_merge_def(uapi, ibdev, uverbs_core_api, false);657	if (rc)658		goto err;659	rc = uapi_merge_def(uapi, ibdev, ibdev->driver_def, true);660	if (rc)661		goto err;662 663	uapi_finalize_disable(uapi);664	rc = uapi_finalize(uapi);665	if (rc)666		goto err;667 668	return uapi;669err:670	if (rc != -ENOMEM)671		dev_err(&ibdev->dev,672			"Setup of uverbs_api failed, kernel parsing tree description is not valid (%d)??\n",673			rc);674 675	uverbs_destroy_api(uapi);676	return ERR_PTR(rc);677}678 679/*680 * The pre version is done before destroying the HW objects, it only blocks681 * off method access. All methods that require the ib_dev or the module data682 * must test one of these assignments prior to continuing.683 */684void uverbs_disassociate_api_pre(struct ib_uverbs_device *uverbs_dev)685{686	struct uverbs_api *uapi = uverbs_dev->uapi;687	struct radix_tree_iter iter;688	void __rcu **slot;689 690	rcu_assign_pointer(uverbs_dev->ib_dev, NULL);691 692	radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) {693		if (uapi_key_is_ioctl_method(iter.index)) {694			struct uverbs_api_ioctl_method *method_elm =695				rcu_dereference_protected(*slot, true);696 697			if (method_elm->driver_method)698				rcu_assign_pointer(method_elm->handler, NULL);699		}700	}701 702	synchronize_srcu(&uverbs_dev->disassociate_srcu);703}704 705/*706 * Called when a driver disassociates from the ib_uverbs_device. The707 * assumption is that the driver module will unload after. Replace everything708 * related to the driver with NULL as a safety measure.709 */710void uverbs_disassociate_api(struct uverbs_api *uapi)711{712	struct radix_tree_iter iter;713	void __rcu **slot;714 715	radix_tree_for_each_slot (slot, &uapi->radix, &iter, 0) {716		if (uapi_key_is_object(iter.index)) {717			struct uverbs_api_object *object_elm =718				rcu_dereference_protected(*slot, true);719 720			/*721			 * Some type_attrs are in the driver module. We don't722			 * bother to keep track of which since there should be723			 * no use of this after disassociate.724			 */725			object_elm->type_attrs = NULL;726		} else if (uapi_key_is_attr(iter.index)) {727			struct uverbs_api_attr *elm =728				rcu_dereference_protected(*slot, true);729 730			if (elm->spec.type == UVERBS_ATTR_TYPE_ENUM_IN)731				elm->spec.u2.enum_def.ids = NULL;732		}733	}734}735