xref: /kernel/linux/linux-6.6/drivers/tee/optee/core.c (revision 62306a36)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2015-2021, Linaro Limited
4 * Copyright (c) 2016, EPAM Systems
5 */
6
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9#include <linux/crash_dump.h>
10#include <linux/errno.h>
11#include <linux/io.h>
12#include <linux/mm.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15#include <linux/string.h>
16#include <linux/tee_drv.h>
17#include <linux/types.h>
18#include <linux/workqueue.h>
19#include "optee_private.h"
20
21int optee_pool_op_alloc_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
22			       size_t size, size_t align,
23			       int (*shm_register)(struct tee_context *ctx,
24						   struct tee_shm *shm,
25						   struct page **pages,
26						   size_t num_pages,
27						   unsigned long start))
28{
29	unsigned int order = get_order(size);
30	struct page *page;
31	int rc = 0;
32
33	/*
34	 * Ignore alignment since this is already going to be page aligned
35	 * and there's no need for any larger alignment.
36	 */
37	page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
38	if (!page)
39		return -ENOMEM;
40
41	shm->kaddr = page_address(page);
42	shm->paddr = page_to_phys(page);
43	shm->size = PAGE_SIZE << order;
44
45	if (shm_register) {
46		unsigned int nr_pages = 1 << order, i;
47		struct page **pages;
48
49		pages = kcalloc(nr_pages, sizeof(*pages), GFP_KERNEL);
50		if (!pages) {
51			rc = -ENOMEM;
52			goto err;
53		}
54
55		for (i = 0; i < nr_pages; i++)
56			pages[i] = page + i;
57
58		rc = shm_register(shm->ctx, shm, pages, nr_pages,
59				  (unsigned long)shm->kaddr);
60		kfree(pages);
61		if (rc)
62			goto err;
63	}
64
65	return 0;
66
67err:
68	free_pages((unsigned long)shm->kaddr, order);
69	return rc;
70}
71
72void optee_pool_op_free_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
73			       int (*shm_unregister)(struct tee_context *ctx,
74						     struct tee_shm *shm))
75{
76	if (shm_unregister)
77		shm_unregister(shm->ctx, shm);
78	free_pages((unsigned long)shm->kaddr, get_order(shm->size));
79	shm->kaddr = NULL;
80}
81
82static void optee_bus_scan(struct work_struct *work)
83{
84	WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
85}
86
87int optee_open(struct tee_context *ctx, bool cap_memref_null)
88{
89	struct optee_context_data *ctxdata;
90	struct tee_device *teedev = ctx->teedev;
91	struct optee *optee = tee_get_drvdata(teedev);
92
93	ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
94	if (!ctxdata)
95		return -ENOMEM;
96
97	if (teedev == optee->supp_teedev) {
98		bool busy = true;
99
100		mutex_lock(&optee->supp.mutex);
101		if (!optee->supp.ctx) {
102			busy = false;
103			optee->supp.ctx = ctx;
104		}
105		mutex_unlock(&optee->supp.mutex);
106		if (busy) {
107			kfree(ctxdata);
108			return -EBUSY;
109		}
110
111		if (!optee->scan_bus_done) {
112			INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
113			optee->scan_bus_wq = create_workqueue("optee_bus_scan");
114			if (!optee->scan_bus_wq) {
115				kfree(ctxdata);
116				return -ECHILD;
117			}
118			queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
119			optee->scan_bus_done = true;
120		}
121	}
122	mutex_init(&ctxdata->mutex);
123	INIT_LIST_HEAD(&ctxdata->sess_list);
124
125	ctx->cap_memref_null = cap_memref_null;
126	ctx->data = ctxdata;
127	return 0;
128}
129
130static void optee_release_helper(struct tee_context *ctx,
131				 int (*close_session)(struct tee_context *ctx,
132						      u32 session))
133{
134	struct optee_context_data *ctxdata = ctx->data;
135	struct optee_session *sess;
136	struct optee_session *sess_tmp;
137
138	if (!ctxdata)
139		return;
140
141	list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
142				 list_node) {
143		list_del(&sess->list_node);
144		close_session(ctx, sess->session_id);
145		kfree(sess);
146	}
147	kfree(ctxdata);
148	ctx->data = NULL;
149}
150
151void optee_release(struct tee_context *ctx)
152{
153	optee_release_helper(ctx, optee_close_session_helper);
154}
155
156void optee_release_supp(struct tee_context *ctx)
157{
158	struct optee *optee = tee_get_drvdata(ctx->teedev);
159
160	optee_release_helper(ctx, optee_close_session_helper);
161	if (optee->scan_bus_wq) {
162		destroy_workqueue(optee->scan_bus_wq);
163		optee->scan_bus_wq = NULL;
164	}
165	optee_supp_release(&optee->supp);
166}
167
168void optee_remove_common(struct optee *optee)
169{
170	/* Unregister OP-TEE specific client devices on TEE bus */
171	optee_unregister_devices();
172
173	optee_notif_uninit(optee);
174	optee_shm_arg_cache_uninit(optee);
175	teedev_close_context(optee->ctx);
176	/*
177	 * The two devices have to be unregistered before we can free the
178	 * other resources.
179	 */
180	tee_device_unregister(optee->supp_teedev);
181	tee_device_unregister(optee->teedev);
182
183	tee_shm_pool_free(optee->pool);
184	optee_supp_uninit(&optee->supp);
185	mutex_destroy(&optee->call_queue.mutex);
186}
187
188static int smc_abi_rc;
189static int ffa_abi_rc;
190
191static int __init optee_core_init(void)
192{
193	/*
194	 * The kernel may have crashed at the same time that all available
195	 * secure world threads were suspended and we cannot reschedule the
196	 * suspended threads without access to the crashed kernel's wait_queue.
197	 * Therefore, we cannot reliably initialize the OP-TEE driver in the
198	 * kdump kernel.
199	 */
200	if (is_kdump_kernel())
201		return -ENODEV;
202
203	smc_abi_rc = optee_smc_abi_register();
204	ffa_abi_rc = optee_ffa_abi_register();
205
206	/* If both failed there's no point with this module */
207	if (smc_abi_rc && ffa_abi_rc)
208		return smc_abi_rc;
209	return 0;
210}
211module_init(optee_core_init);
212
213static void __exit optee_core_exit(void)
214{
215	if (!smc_abi_rc)
216		optee_smc_abi_unregister();
217	if (!ffa_abi_rc)
218		optee_ffa_abi_unregister();
219}
220module_exit(optee_core_exit);
221
222MODULE_AUTHOR("Linaro");
223MODULE_DESCRIPTION("OP-TEE driver");
224MODULE_VERSION("1.0");
225MODULE_LICENSE("GPL v2");
226MODULE_ALIAS("platform:optee");
227