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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2015-2021, 2023 Linaro Limited4 */5#include <linux/device.h>6#include <linux/err.h>7#include <linux/errno.h>8#include <linux/mm.h>9#include <linux/slab.h>10#include <linux/tee_core.h>11#include <linux/types.h>12#include "optee_private.h"13 14#define MAX_ARG_PARAM_COUNT	615 16/*17 * How much memory we allocate for each entry. This doesn't have to be a18 * single page, but it makes sense to keep at least keep it as multiples of19 * the page size.20 */21#define SHM_ENTRY_SIZE		PAGE_SIZE22 23/*24 * We need to have a compile time constant to be able to determine the25 * maximum needed size of the bit field.26 */27#define MIN_ARG_SIZE		OPTEE_MSG_GET_ARG_SIZE(MAX_ARG_PARAM_COUNT)28#define MAX_ARG_COUNT_PER_ENTRY	(SHM_ENTRY_SIZE / MIN_ARG_SIZE)29 30/*31 * Shared memory for argument structs are cached here. The number of32 * arguments structs that can fit is determined at runtime depending on the33 * needed RPC parameter count reported by secure world34 * (optee->rpc_param_count).35 */36struct optee_shm_arg_entry {37	struct list_head list_node;38	struct tee_shm *shm;39	DECLARE_BITMAP(map, MAX_ARG_COUNT_PER_ENTRY);40};41 42void optee_cq_init(struct optee_call_queue *cq, int thread_count)43{44	mutex_init(&cq->mutex);45	INIT_LIST_HEAD(&cq->waiters);46 47	/*48	 * If cq->total_thread_count is 0 then we're not trying to keep49	 * track of how many free threads we have, instead we're relying on50	 * the secure world to tell us when we're out of thread and have to51	 * wait for another thread to become available.52	 */53	cq->total_thread_count = thread_count;54	cq->free_thread_count = thread_count;55}56 57void optee_cq_wait_init(struct optee_call_queue *cq,58			struct optee_call_waiter *w, bool sys_thread)59{60	unsigned int free_thread_threshold;61	bool need_wait = false;62 63	memset(w, 0, sizeof(*w));64 65	/*66	 * We're preparing to make a call to secure world. In case we can't67	 * allocate a thread in secure world we'll end up waiting in68	 * optee_cq_wait_for_completion().69	 *70	 * Normally if there's no contention in secure world the call will71	 * complete and we can cleanup directly with optee_cq_wait_final().72	 */73	mutex_lock(&cq->mutex);74 75	/*76	 * We add ourselves to the queue, but we don't wait. This77	 * guarantees that we don't lose a completion if secure world78	 * returns busy and another thread just exited and try to complete79	 * someone.80	 */81	init_completion(&w->c);82	list_add_tail(&w->list_node, &cq->waiters);83	w->sys_thread = sys_thread;84 85	if (cq->total_thread_count) {86		if (sys_thread || !cq->sys_thread_req_count)87			free_thread_threshold = 0;88		else89			free_thread_threshold = 1;90 91		if (cq->free_thread_count > free_thread_threshold)92			cq->free_thread_count--;93		else94			need_wait = true;95	}96 97	mutex_unlock(&cq->mutex);98 99	while (need_wait) {100		optee_cq_wait_for_completion(cq, w);101		mutex_lock(&cq->mutex);102 103		if (sys_thread || !cq->sys_thread_req_count)104			free_thread_threshold = 0;105		else106			free_thread_threshold = 1;107 108		if (cq->free_thread_count > free_thread_threshold) {109			cq->free_thread_count--;110			need_wait = false;111		}112 113		mutex_unlock(&cq->mutex);114	}115}116 117void optee_cq_wait_for_completion(struct optee_call_queue *cq,118				  struct optee_call_waiter *w)119{120	wait_for_completion(&w->c);121 122	mutex_lock(&cq->mutex);123 124	/* Move to end of list to get out of the way for other waiters */125	list_del(&w->list_node);126	reinit_completion(&w->c);127	list_add_tail(&w->list_node, &cq->waiters);128 129	mutex_unlock(&cq->mutex);130}131 132static void optee_cq_complete_one(struct optee_call_queue *cq)133{134	struct optee_call_waiter *w;135 136	/* Wake a waiting system session if any, prior to a normal session */137	list_for_each_entry(w, &cq->waiters, list_node) {138		if (w->sys_thread && !completion_done(&w->c)) {139			complete(&w->c);140			return;141		}142	}143 144	list_for_each_entry(w, &cq->waiters, list_node) {145		if (!completion_done(&w->c)) {146			complete(&w->c);147			break;148		}149	}150}151 152void optee_cq_wait_final(struct optee_call_queue *cq,153			 struct optee_call_waiter *w)154{155	/*156	 * We're done with the call to secure world. The thread in secure157	 * world that was used for this call is now available for some158	 * other task to use.159	 */160	mutex_lock(&cq->mutex);161 162	/* Get out of the list */163	list_del(&w->list_node);164 165	cq->free_thread_count++;166 167	/* Wake up one eventual waiting task */168	optee_cq_complete_one(cq);169 170	/*171	 * If we're completed we've got a completion from another task that172	 * was just done with its call to secure world. Since yet another173	 * thread now is available in secure world wake up another eventual174	 * waiting task.175	 */176	if (completion_done(&w->c))177		optee_cq_complete_one(cq);178 179	mutex_unlock(&cq->mutex);180}181 182/* Count registered system sessions to reserved a system thread or not */183static bool optee_cq_incr_sys_thread_count(struct optee_call_queue *cq)184{185	if (cq->total_thread_count <= 1)186		return false;187 188	mutex_lock(&cq->mutex);189	cq->sys_thread_req_count++;190	mutex_unlock(&cq->mutex);191 192	return true;193}194 195static void optee_cq_decr_sys_thread_count(struct optee_call_queue *cq)196{197	mutex_lock(&cq->mutex);198	cq->sys_thread_req_count--;199	/* If there's someone waiting, let it resume */200	optee_cq_complete_one(cq);201	mutex_unlock(&cq->mutex);202}203 204/* Requires the filpstate mutex to be held */205static struct optee_session *find_session(struct optee_context_data *ctxdata,206					  u32 session_id)207{208	struct optee_session *sess;209 210	list_for_each_entry(sess, &ctxdata->sess_list, list_node)211		if (sess->session_id == session_id)212			return sess;213 214	return NULL;215}216 217void optee_shm_arg_cache_init(struct optee *optee, u32 flags)218{219	INIT_LIST_HEAD(&optee->shm_arg_cache.shm_args);220	mutex_init(&optee->shm_arg_cache.mutex);221	optee->shm_arg_cache.flags = flags;222}223 224void optee_shm_arg_cache_uninit(struct optee *optee)225{226	struct list_head *head = &optee->shm_arg_cache.shm_args;227	struct optee_shm_arg_entry *entry;228 229	mutex_destroy(&optee->shm_arg_cache.mutex);230	while (!list_empty(head)) {231		entry = list_first_entry(head, struct optee_shm_arg_entry,232					 list_node);233		list_del(&entry->list_node);234		if (find_first_bit(entry->map, MAX_ARG_COUNT_PER_ENTRY) !=235		     MAX_ARG_COUNT_PER_ENTRY) {236			pr_err("Freeing non-free entry\n");237		}238		tee_shm_free(entry->shm);239		kfree(entry);240	}241}242 243size_t optee_msg_arg_size(size_t rpc_param_count)244{245	size_t sz = OPTEE_MSG_GET_ARG_SIZE(MAX_ARG_PARAM_COUNT);246 247	if (rpc_param_count)248		sz += OPTEE_MSG_GET_ARG_SIZE(rpc_param_count);249 250	return sz;251}252 253/**254 * optee_get_msg_arg() - Provide shared memory for argument struct255 * @ctx:	Caller TEE context256 * @num_params:	Number of parameter to store257 * @entry_ret:	Entry pointer, needed when freeing the buffer258 * @shm_ret:	Shared memory buffer259 * @offs_ret:	Offset of argument strut in shared memory buffer260 *261 * @returns a pointer to the argument struct in memory, else an ERR_PTR262 */263struct optee_msg_arg *optee_get_msg_arg(struct tee_context *ctx,264					size_t num_params,265					struct optee_shm_arg_entry **entry_ret,266					struct tee_shm **shm_ret,267					u_int *offs_ret)268{269	struct optee *optee = tee_get_drvdata(ctx->teedev);270	size_t sz = optee_msg_arg_size(optee->rpc_param_count);271	struct optee_shm_arg_entry *entry;272	struct optee_msg_arg *ma;273	size_t args_per_entry;274	u_long bit;275	u_int offs;276	void *res;277 278	if (num_params > MAX_ARG_PARAM_COUNT)279		return ERR_PTR(-EINVAL);280 281	if (optee->shm_arg_cache.flags & OPTEE_SHM_ARG_SHARED)282		args_per_entry = SHM_ENTRY_SIZE / sz;283	else284		args_per_entry = 1;285 286	mutex_lock(&optee->shm_arg_cache.mutex);287	list_for_each_entry(entry, &optee->shm_arg_cache.shm_args, list_node) {288		bit = find_first_zero_bit(entry->map, MAX_ARG_COUNT_PER_ENTRY);289		if (bit < args_per_entry)290			goto have_entry;291	}292 293	/*294	 * No entry was found, let's allocate a new.295	 */296	entry = kzalloc(sizeof(*entry), GFP_KERNEL);297	if (!entry) {298		res = ERR_PTR(-ENOMEM);299		goto out;300	}301 302	if (optee->shm_arg_cache.flags & OPTEE_SHM_ARG_ALLOC_PRIV)303		res = tee_shm_alloc_priv_buf(ctx, SHM_ENTRY_SIZE);304	else305		res = tee_shm_alloc_kernel_buf(ctx, SHM_ENTRY_SIZE);306 307	if (IS_ERR(res)) {308		kfree(entry);309		goto out;310	}311	entry->shm = res;312	list_add(&entry->list_node, &optee->shm_arg_cache.shm_args);313	bit = 0;314 315have_entry:316	offs = bit * sz;317	res = tee_shm_get_va(entry->shm, offs);318	if (IS_ERR(res))319		goto out;320	ma = res;321	set_bit(bit, entry->map);322	memset(ma, 0, sz);323	ma->num_params = num_params;324	*entry_ret = entry;325	*shm_ret = entry->shm;326	*offs_ret = offs;327out:328	mutex_unlock(&optee->shm_arg_cache.mutex);329	return res;330}331 332/**333 * optee_free_msg_arg() - Free previsouly obtained shared memory334 * @ctx:	Caller TEE context335 * @entry:	Pointer returned when the shared memory was obtained336 * @offs:	Offset of shared memory buffer to free337 *338 * This function frees the shared memory obtained with optee_get_msg_arg().339 */340void optee_free_msg_arg(struct tee_context *ctx,341			struct optee_shm_arg_entry *entry, u_int offs)342{343	struct optee *optee = tee_get_drvdata(ctx->teedev);344	size_t sz = optee_msg_arg_size(optee->rpc_param_count);345	u_long bit;346 347	if (offs > SHM_ENTRY_SIZE || offs % sz) {348		pr_err("Invalid offs %u\n", offs);349		return;350	}351	bit = offs / sz;352 353	mutex_lock(&optee->shm_arg_cache.mutex);354 355	if (!test_bit(bit, entry->map))356		pr_err("Bit pos %lu is already free\n", bit);357	clear_bit(bit, entry->map);358 359	mutex_unlock(&optee->shm_arg_cache.mutex);360}361 362int optee_open_session(struct tee_context *ctx,363		       struct tee_ioctl_open_session_arg *arg,364		       struct tee_param *param)365{366	struct optee *optee = tee_get_drvdata(ctx->teedev);367	struct optee_context_data *ctxdata = ctx->data;368	struct optee_shm_arg_entry *entry;369	struct tee_shm *shm;370	struct optee_msg_arg *msg_arg;371	struct optee_session *sess = NULL;372	uuid_t client_uuid;373	u_int offs;374	int rc;375 376	/* +2 for the meta parameters added below */377	msg_arg = optee_get_msg_arg(ctx, arg->num_params + 2,378				    &entry, &shm, &offs);379	if (IS_ERR(msg_arg))380		return PTR_ERR(msg_arg);381 382	msg_arg->cmd = OPTEE_MSG_CMD_OPEN_SESSION;383	msg_arg->cancel_id = arg->cancel_id;384 385	/*386	 * Initialize and add the meta parameters needed when opening a387	 * session.388	 */389	msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT |390				  OPTEE_MSG_ATTR_META;391	msg_arg->params[1].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT |392				  OPTEE_MSG_ATTR_META;393	memcpy(&msg_arg->params[0].u.value, arg->uuid, sizeof(arg->uuid));394	msg_arg->params[1].u.value.c = arg->clnt_login;395 396	rc = tee_session_calc_client_uuid(&client_uuid, arg->clnt_login,397					  arg->clnt_uuid);398	if (rc)399		goto out;400	export_uuid(msg_arg->params[1].u.octets, &client_uuid);401 402	rc = optee->ops->to_msg_param(optee, msg_arg->params + 2,403				      arg->num_params, param);404	if (rc)405		goto out;406 407	sess = kzalloc(sizeof(*sess), GFP_KERNEL);408	if (!sess) {409		rc = -ENOMEM;410		goto out;411	}412 413	if (optee->ops->do_call_with_arg(ctx, shm, offs,414					 sess->use_sys_thread)) {415		msg_arg->ret = TEEC_ERROR_COMMUNICATION;416		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;417	}418 419	if (msg_arg->ret == TEEC_SUCCESS) {420		/* A new session has been created, add it to the list. */421		sess->session_id = msg_arg->session;422		mutex_lock(&ctxdata->mutex);423		list_add(&sess->list_node, &ctxdata->sess_list);424		mutex_unlock(&ctxdata->mutex);425	} else {426		kfree(sess);427	}428 429	if (optee->ops->from_msg_param(optee, param, arg->num_params,430				       msg_arg->params + 2)) {431		arg->ret = TEEC_ERROR_COMMUNICATION;432		arg->ret_origin = TEEC_ORIGIN_COMMS;433		/* Close session again to avoid leakage */434		optee_close_session(ctx, msg_arg->session);435	} else {436		arg->session = msg_arg->session;437		arg->ret = msg_arg->ret;438		arg->ret_origin = msg_arg->ret_origin;439	}440out:441	optee_free_msg_arg(ctx, entry, offs);442 443	return rc;444}445 446int optee_system_session(struct tee_context *ctx, u32 session)447{448	struct optee *optee = tee_get_drvdata(ctx->teedev);449	struct optee_context_data *ctxdata = ctx->data;450	struct optee_session *sess;451	int rc = -EINVAL;452 453	mutex_lock(&ctxdata->mutex);454 455	sess = find_session(ctxdata, session);456	if (sess && (sess->use_sys_thread ||457		     optee_cq_incr_sys_thread_count(&optee->call_queue))) {458		sess->use_sys_thread = true;459		rc = 0;460	}461 462	mutex_unlock(&ctxdata->mutex);463 464	return rc;465}466 467int optee_close_session_helper(struct tee_context *ctx, u32 session,468			       bool system_thread)469{470	struct optee *optee = tee_get_drvdata(ctx->teedev);471	struct optee_shm_arg_entry *entry;472	struct optee_msg_arg *msg_arg;473	struct tee_shm *shm;474	u_int offs;475 476	msg_arg = optee_get_msg_arg(ctx, 0, &entry, &shm, &offs);477	if (IS_ERR(msg_arg))478		return PTR_ERR(msg_arg);479 480	msg_arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;481	msg_arg->session = session;482	optee->ops->do_call_with_arg(ctx, shm, offs, system_thread);483 484	optee_free_msg_arg(ctx, entry, offs);485 486	if (system_thread)487		optee_cq_decr_sys_thread_count(&optee->call_queue);488 489	return 0;490}491 492int optee_close_session(struct tee_context *ctx, u32 session)493{494	struct optee_context_data *ctxdata = ctx->data;495	struct optee_session *sess;496	bool system_thread;497 498	/* Check that the session is valid and remove it from the list */499	mutex_lock(&ctxdata->mutex);500	sess = find_session(ctxdata, session);501	if (sess)502		list_del(&sess->list_node);503	mutex_unlock(&ctxdata->mutex);504	if (!sess)505		return -EINVAL;506	system_thread = sess->use_sys_thread;507	kfree(sess);508 509	return optee_close_session_helper(ctx, session, system_thread);510}511 512int optee_invoke_func(struct tee_context *ctx, struct tee_ioctl_invoke_arg *arg,513		      struct tee_param *param)514{515	struct optee *optee = tee_get_drvdata(ctx->teedev);516	struct optee_context_data *ctxdata = ctx->data;517	struct optee_shm_arg_entry *entry;518	struct optee_msg_arg *msg_arg;519	struct optee_session *sess;520	struct tee_shm *shm;521	bool system_thread;522	u_int offs;523	int rc;524 525	/* Check that the session is valid */526	mutex_lock(&ctxdata->mutex);527	sess = find_session(ctxdata, arg->session);528	if (sess)529		system_thread = sess->use_sys_thread;530	mutex_unlock(&ctxdata->mutex);531	if (!sess)532		return -EINVAL;533 534	msg_arg = optee_get_msg_arg(ctx, arg->num_params,535				    &entry, &shm, &offs);536	if (IS_ERR(msg_arg))537		return PTR_ERR(msg_arg);538	msg_arg->cmd = OPTEE_MSG_CMD_INVOKE_COMMAND;539	msg_arg->func = arg->func;540	msg_arg->session = arg->session;541	msg_arg->cancel_id = arg->cancel_id;542 543	rc = optee->ops->to_msg_param(optee, msg_arg->params, arg->num_params,544				      param);545	if (rc)546		goto out;547 548	if (optee->ops->do_call_with_arg(ctx, shm, offs, system_thread)) {549		msg_arg->ret = TEEC_ERROR_COMMUNICATION;550		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;551	}552 553	if (optee->ops->from_msg_param(optee, param, arg->num_params,554				       msg_arg->params)) {555		msg_arg->ret = TEEC_ERROR_COMMUNICATION;556		msg_arg->ret_origin = TEEC_ORIGIN_COMMS;557	}558 559	arg->ret = msg_arg->ret;560	arg->ret_origin = msg_arg->ret_origin;561out:562	optee_free_msg_arg(ctx, entry, offs);563	return rc;564}565 566int optee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)567{568	struct optee *optee = tee_get_drvdata(ctx->teedev);569	struct optee_context_data *ctxdata = ctx->data;570	struct optee_shm_arg_entry *entry;571	struct optee_msg_arg *msg_arg;572	struct optee_session *sess;573	bool system_thread;574	struct tee_shm *shm;575	u_int offs;576 577	/* Check that the session is valid */578	mutex_lock(&ctxdata->mutex);579	sess = find_session(ctxdata, session);580	if (sess)581		system_thread = sess->use_sys_thread;582	mutex_unlock(&ctxdata->mutex);583	if (!sess)584		return -EINVAL;585 586	msg_arg = optee_get_msg_arg(ctx, 0, &entry, &shm, &offs);587	if (IS_ERR(msg_arg))588		return PTR_ERR(msg_arg);589 590	msg_arg->cmd = OPTEE_MSG_CMD_CANCEL;591	msg_arg->session = session;592	msg_arg->cancel_id = cancel_id;593	optee->ops->do_call_with_arg(ctx, shm, offs, system_thread);594 595	optee_free_msg_arg(ctx, entry, offs);596	return 0;597}598 599static bool is_normal_memory(pgprot_t p)600{601#if defined(CONFIG_ARM)602	return (((pgprot_val(p) & L_PTE_MT_MASK) == L_PTE_MT_WRITEALLOC) ||603		((pgprot_val(p) & L_PTE_MT_MASK) == L_PTE_MT_WRITEBACK));604#elif defined(CONFIG_ARM64)605	return (pgprot_val(p) & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL);606#else607#error "Unsupported architecture"608#endif609}610 611static int __check_mem_type(struct mm_struct *mm, unsigned long start,612				unsigned long end)613{614	struct vm_area_struct *vma;615	VMA_ITERATOR(vmi, mm, start);616 617	for_each_vma_range(vmi, vma, end) {618		if (!is_normal_memory(vma->vm_page_prot))619			return -EINVAL;620	}621 622	return 0;623}624 625int optee_check_mem_type(unsigned long start, size_t num_pages)626{627	struct mm_struct *mm = current->mm;628	int rc;629 630	/*631	 * Allow kernel address to register with OP-TEE as kernel632	 * pages are configured as normal memory only.633	 */634	if (virt_addr_valid((void *)start) || is_vmalloc_addr((void *)start))635		return 0;636 637	mmap_read_lock(mm);638	rc = __check_mem_type(mm, start, start + num_pages * PAGE_SIZE);639	mmap_read_unlock(mm);640 641	return rc;642}643 644static int simple_call_with_arg(struct tee_context *ctx, u32 cmd)645{646	struct optee *optee = tee_get_drvdata(ctx->teedev);647	struct optee_shm_arg_entry *entry;648	struct optee_msg_arg *msg_arg;649	struct tee_shm *shm;650	u_int offs;651 652	msg_arg = optee_get_msg_arg(ctx, 0, &entry, &shm, &offs);653	if (IS_ERR(msg_arg))654		return PTR_ERR(msg_arg);655 656	msg_arg->cmd = cmd;657	optee->ops->do_call_with_arg(ctx, shm, offs, false);658 659	optee_free_msg_arg(ctx, entry, offs);660	return 0;661}662 663int optee_do_bottom_half(struct tee_context *ctx)664{665	return simple_call_with_arg(ctx, OPTEE_MSG_CMD_DO_BOTTOM_HALF);666}667 668int optee_stop_async_notif(struct tee_context *ctx)669{670	return simple_call_with_arg(ctx, OPTEE_MSG_CMD_STOP_ASYNC_NOTIF);671}672