1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright 2019 Advanced Micro Devices, Inc.
4 */
5
6 #include <linux/errno.h>
7 #include <linux/io.h>
8 #include <linux/module.h>
9 #include <linux/slab.h>
10 #include <linux/string.h>
11 #include <linux/device.h>
12 #include <linux/tee_drv.h>
13 #include <linux/types.h>
14 #include <linux/mm.h>
15 #include <linux/uaccess.h>
16 #include <linux/firmware.h>
17 #include "amdtee_private.h"
18 #include "../tee_private.h"
19 #include <linux/psp-tee.h>
20
21 static struct amdtee_driver_data *drv_data;
22 static DEFINE_MUTEX(session_list_mutex);
23
amdtee_get_version(struct tee_device * teedev,struct tee_ioctl_version_data * vers)24 static void amdtee_get_version(struct tee_device *teedev,
25 struct tee_ioctl_version_data *vers)
26 {
27 struct tee_ioctl_version_data v = {
28 .impl_id = TEE_IMPL_ID_AMDTEE,
29 .impl_caps = 0,
30 .gen_caps = TEE_GEN_CAP_GP,
31 };
32 *vers = v;
33 }
34
amdtee_open(struct tee_context * ctx)35 static int amdtee_open(struct tee_context *ctx)
36 {
37 struct amdtee_context_data *ctxdata;
38
39 ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
40 if (!ctxdata)
41 return -ENOMEM;
42
43 INIT_LIST_HEAD(&ctxdata->sess_list);
44 INIT_LIST_HEAD(&ctxdata->shm_list);
45 mutex_init(&ctxdata->shm_mutex);
46
47 ctx->data = ctxdata;
48 return 0;
49 }
50
release_session(struct amdtee_session * sess)51 static void release_session(struct amdtee_session *sess)
52 {
53 int i;
54
55 /* Close any open session */
56 for (i = 0; i < TEE_NUM_SESSIONS; ++i) {
57 /* Check if session entry 'i' is valid */
58 if (!test_bit(i, sess->sess_mask))
59 continue;
60
61 handle_close_session(sess->ta_handle, sess->session_info[i]);
62 handle_unload_ta(sess->ta_handle);
63 }
64
65 kfree(sess);
66 }
67
amdtee_release(struct tee_context * ctx)68 static void amdtee_release(struct tee_context *ctx)
69 {
70 struct amdtee_context_data *ctxdata = ctx->data;
71
72 if (!ctxdata)
73 return;
74
75 while (true) {
76 struct amdtee_session *sess;
77
78 sess = list_first_entry_or_null(&ctxdata->sess_list,
79 struct amdtee_session,
80 list_node);
81
82 if (!sess)
83 break;
84
85 list_del(&sess->list_node);
86 release_session(sess);
87 }
88 mutex_destroy(&ctxdata->shm_mutex);
89 kfree(ctxdata);
90
91 ctx->data = NULL;
92 }
93
94 /**
95 * alloc_session() - Allocate a session structure
96 * @ctxdata: TEE Context data structure
97 * @session: Session ID for which 'struct amdtee_session' structure is to be
98 * allocated.
99 *
100 * Scans the TEE context's session list to check if TA is already loaded in to
101 * TEE. If yes, returns the 'session' structure for that TA. Else allocates,
102 * initializes a new 'session' structure and adds it to context's session list.
103 *
104 * The caller must hold a mutex.
105 *
106 * Returns:
107 * 'struct amdtee_session *' on success and NULL on failure.
108 */
alloc_session(struct amdtee_context_data * ctxdata,u32 session)109 static struct amdtee_session *alloc_session(struct amdtee_context_data *ctxdata,
110 u32 session)
111 {
112 struct amdtee_session *sess;
113 u32 ta_handle = get_ta_handle(session);
114
115 /* Scan session list to check if TA is already loaded in to TEE */
116 list_for_each_entry(sess, &ctxdata->sess_list, list_node)
117 if (sess->ta_handle == ta_handle) {
118 kref_get(&sess->refcount);
119 return sess;
120 }
121
122 /* Allocate a new session and add to list */
123 sess = kzalloc(sizeof(*sess), GFP_KERNEL);
124 if (sess) {
125 sess->ta_handle = ta_handle;
126 kref_init(&sess->refcount);
127 spin_lock_init(&sess->lock);
128 list_add(&sess->list_node, &ctxdata->sess_list);
129 }
130
131 return sess;
132 }
133
134 /* Requires mutex to be held */
find_session(struct amdtee_context_data * ctxdata,u32 session)135 static struct amdtee_session *find_session(struct amdtee_context_data *ctxdata,
136 u32 session)
137 {
138 u32 ta_handle = get_ta_handle(session);
139 u32 index = get_session_index(session);
140 struct amdtee_session *sess;
141
142 if (index >= TEE_NUM_SESSIONS)
143 return NULL;
144
145 list_for_each_entry(sess, &ctxdata->sess_list, list_node)
146 if (ta_handle == sess->ta_handle &&
147 test_bit(index, sess->sess_mask))
148 return sess;
149
150 return NULL;
151 }
152
get_buffer_id(struct tee_shm * shm)153 u32 get_buffer_id(struct tee_shm *shm)
154 {
155 struct amdtee_context_data *ctxdata = shm->ctx->data;
156 struct amdtee_shm_data *shmdata;
157 u32 buf_id = 0;
158
159 mutex_lock(&ctxdata->shm_mutex);
160 list_for_each_entry(shmdata, &ctxdata->shm_list, shm_node)
161 if (shmdata->kaddr == shm->kaddr) {
162 buf_id = shmdata->buf_id;
163 break;
164 }
165 mutex_unlock(&ctxdata->shm_mutex);
166
167 return buf_id;
168 }
169
170 static DEFINE_MUTEX(drv_mutex);
copy_ta_binary(struct tee_context * ctx,void * ptr,void ** ta,size_t * ta_size)171 static int copy_ta_binary(struct tee_context *ctx, void *ptr, void **ta,
172 size_t *ta_size)
173 {
174 const struct firmware *fw;
175 char fw_name[TA_PATH_MAX];
176 struct {
177 u32 lo;
178 u16 mid;
179 u16 hi_ver;
180 u8 seq_n[8];
181 } *uuid = ptr;
182 int n, rc = 0;
183
184 n = snprintf(fw_name, TA_PATH_MAX,
185 "%s/%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x.bin",
186 TA_LOAD_PATH, uuid->lo, uuid->mid, uuid->hi_ver,
187 uuid->seq_n[0], uuid->seq_n[1],
188 uuid->seq_n[2], uuid->seq_n[3],
189 uuid->seq_n[4], uuid->seq_n[5],
190 uuid->seq_n[6], uuid->seq_n[7]);
191 if (n < 0 || n >= TA_PATH_MAX) {
192 pr_err("failed to get firmware name\n");
193 return -EINVAL;
194 }
195
196 mutex_lock(&drv_mutex);
197 n = request_firmware(&fw, fw_name, &ctx->teedev->dev);
198 if (n) {
199 pr_err("failed to load firmware %s\n", fw_name);
200 rc = -ENOMEM;
201 goto unlock;
202 }
203
204 *ta_size = roundup(fw->size, PAGE_SIZE);
205 *ta = (void *)__get_free_pages(GFP_KERNEL, get_order(*ta_size));
206 if (!*ta) {
207 pr_err("%s: get_free_pages failed\n", __func__);
208 rc = -ENOMEM;
209 goto rel_fw;
210 }
211
212 memcpy(*ta, fw->data, fw->size);
213 rel_fw:
214 release_firmware(fw);
215 unlock:
216 mutex_unlock(&drv_mutex);
217 return rc;
218 }
219
destroy_session(struct kref * ref)220 static void destroy_session(struct kref *ref)
221 {
222 struct amdtee_session *sess = container_of(ref, struct amdtee_session,
223 refcount);
224
225 mutex_lock(&session_list_mutex);
226 list_del(&sess->list_node);
227 mutex_unlock(&session_list_mutex);
228 kfree(sess);
229 }
230
amdtee_open_session(struct tee_context * ctx,struct tee_ioctl_open_session_arg * arg,struct tee_param * param)231 int amdtee_open_session(struct tee_context *ctx,
232 struct tee_ioctl_open_session_arg *arg,
233 struct tee_param *param)
234 {
235 struct amdtee_context_data *ctxdata = ctx->data;
236 struct amdtee_session *sess = NULL;
237 u32 session_info, ta_handle;
238 size_t ta_size;
239 int rc, i;
240 void *ta;
241
242 if (arg->clnt_login != TEE_IOCTL_LOGIN_PUBLIC) {
243 pr_err("unsupported client login method\n");
244 return -EINVAL;
245 }
246
247 rc = copy_ta_binary(ctx, &arg->uuid[0], &ta, &ta_size);
248 if (rc) {
249 pr_err("failed to copy TA binary\n");
250 return rc;
251 }
252
253 /* Load the TA binary into TEE environment */
254 handle_load_ta(ta, ta_size, arg);
255 if (arg->ret != TEEC_SUCCESS)
256 goto out;
257
258 ta_handle = get_ta_handle(arg->session);
259
260 mutex_lock(&session_list_mutex);
261 sess = alloc_session(ctxdata, arg->session);
262 mutex_unlock(&session_list_mutex);
263
264 if (!sess) {
265 handle_unload_ta(ta_handle);
266 rc = -ENOMEM;
267 goto out;
268 }
269
270 /* Find an empty session index for the given TA */
271 spin_lock(&sess->lock);
272 i = find_first_zero_bit(sess->sess_mask, TEE_NUM_SESSIONS);
273 if (i < TEE_NUM_SESSIONS)
274 set_bit(i, sess->sess_mask);
275 spin_unlock(&sess->lock);
276
277 if (i >= TEE_NUM_SESSIONS) {
278 pr_err("reached maximum session count %d\n", TEE_NUM_SESSIONS);
279 handle_unload_ta(ta_handle);
280 kref_put(&sess->refcount, destroy_session);
281 rc = -ENOMEM;
282 goto out;
283 }
284
285 /* Open session with loaded TA */
286 handle_open_session(arg, &session_info, param);
287 if (arg->ret != TEEC_SUCCESS) {
288 pr_err("open_session failed %d\n", arg->ret);
289 spin_lock(&sess->lock);
290 clear_bit(i, sess->sess_mask);
291 spin_unlock(&sess->lock);
292 handle_unload_ta(ta_handle);
293 kref_put(&sess->refcount, destroy_session);
294 goto out;
295 }
296
297 sess->session_info[i] = session_info;
298 set_session_id(ta_handle, i, &arg->session);
299 out:
300 free_pages((u64)ta, get_order(ta_size));
301 return rc;
302 }
303
amdtee_close_session(struct tee_context * ctx,u32 session)304 int amdtee_close_session(struct tee_context *ctx, u32 session)
305 {
306 struct amdtee_context_data *ctxdata = ctx->data;
307 u32 i, ta_handle, session_info;
308 struct amdtee_session *sess;
309
310 pr_debug("%s: sid = 0x%x\n", __func__, session);
311
312 /*
313 * Check that the session is valid and clear the session
314 * usage bit
315 */
316 mutex_lock(&session_list_mutex);
317 sess = find_session(ctxdata, session);
318 if (sess) {
319 ta_handle = get_ta_handle(session);
320 i = get_session_index(session);
321 session_info = sess->session_info[i];
322 spin_lock(&sess->lock);
323 clear_bit(i, sess->sess_mask);
324 spin_unlock(&sess->lock);
325 }
326 mutex_unlock(&session_list_mutex);
327
328 if (!sess)
329 return -EINVAL;
330
331 /* Close the session */
332 handle_close_session(ta_handle, session_info);
333 handle_unload_ta(ta_handle);
334
335 kref_put(&sess->refcount, destroy_session);
336
337 return 0;
338 }
339
amdtee_map_shmem(struct tee_shm * shm)340 int amdtee_map_shmem(struct tee_shm *shm)
341 {
342 struct amdtee_context_data *ctxdata;
343 struct amdtee_shm_data *shmnode;
344 struct shmem_desc shmem;
345 int rc, count;
346 u32 buf_id;
347
348 if (!shm)
349 return -EINVAL;
350
351 shmnode = kmalloc(sizeof(*shmnode), GFP_KERNEL);
352 if (!shmnode)
353 return -ENOMEM;
354
355 count = 1;
356 shmem.kaddr = shm->kaddr;
357 shmem.size = shm->size;
358
359 /*
360 * Send a MAP command to TEE and get the corresponding
361 * buffer Id
362 */
363 rc = handle_map_shmem(count, &shmem, &buf_id);
364 if (rc) {
365 pr_err("map_shmem failed: ret = %d\n", rc);
366 kfree(shmnode);
367 return rc;
368 }
369
370 shmnode->kaddr = shm->kaddr;
371 shmnode->buf_id = buf_id;
372 ctxdata = shm->ctx->data;
373 mutex_lock(&ctxdata->shm_mutex);
374 list_add(&shmnode->shm_node, &ctxdata->shm_list);
375 mutex_unlock(&ctxdata->shm_mutex);
376
377 pr_debug("buf_id :[%x] kaddr[%p]\n", shmnode->buf_id, shmnode->kaddr);
378
379 return 0;
380 }
381
amdtee_unmap_shmem(struct tee_shm * shm)382 void amdtee_unmap_shmem(struct tee_shm *shm)
383 {
384 struct amdtee_context_data *ctxdata;
385 struct amdtee_shm_data *shmnode;
386 u32 buf_id;
387
388 if (!shm)
389 return;
390
391 buf_id = get_buffer_id(shm);
392 /* Unmap the shared memory from TEE */
393 handle_unmap_shmem(buf_id);
394
395 ctxdata = shm->ctx->data;
396 mutex_lock(&ctxdata->shm_mutex);
397 list_for_each_entry(shmnode, &ctxdata->shm_list, shm_node)
398 if (buf_id == shmnode->buf_id) {
399 list_del(&shmnode->shm_node);
400 kfree(shmnode);
401 break;
402 }
403 mutex_unlock(&ctxdata->shm_mutex);
404 }
405
amdtee_invoke_func(struct tee_context * ctx,struct tee_ioctl_invoke_arg * arg,struct tee_param * param)406 int amdtee_invoke_func(struct tee_context *ctx,
407 struct tee_ioctl_invoke_arg *arg,
408 struct tee_param *param)
409 {
410 struct amdtee_context_data *ctxdata = ctx->data;
411 struct amdtee_session *sess;
412 u32 i, session_info;
413
414 /* Check that the session is valid */
415 mutex_lock(&session_list_mutex);
416 sess = find_session(ctxdata, arg->session);
417 if (sess) {
418 i = get_session_index(arg->session);
419 session_info = sess->session_info[i];
420 }
421 mutex_unlock(&session_list_mutex);
422
423 if (!sess)
424 return -EINVAL;
425
426 handle_invoke_cmd(arg, session_info, param);
427
428 return 0;
429 }
430
amdtee_cancel_req(struct tee_context * ctx,u32 cancel_id,u32 session)431 int amdtee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
432 {
433 return -EINVAL;
434 }
435
436 static const struct tee_driver_ops amdtee_ops = {
437 .get_version = amdtee_get_version,
438 .open = amdtee_open,
439 .release = amdtee_release,
440 .open_session = amdtee_open_session,
441 .close_session = amdtee_close_session,
442 .invoke_func = amdtee_invoke_func,
443 .cancel_req = amdtee_cancel_req,
444 };
445
446 static const struct tee_desc amdtee_desc = {
447 .name = DRIVER_NAME "-clnt",
448 .ops = &amdtee_ops,
449 .owner = THIS_MODULE,
450 };
451
amdtee_driver_init(void)452 static int __init amdtee_driver_init(void)
453 {
454 struct tee_device *teedev;
455 struct tee_shm_pool *pool;
456 struct amdtee *amdtee;
457 int rc;
458
459 rc = psp_check_tee_status();
460 if (rc) {
461 pr_err("amd-tee driver: tee not present\n");
462 return rc;
463 }
464
465 drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
466 if (!drv_data)
467 return -ENOMEM;
468
469 amdtee = kzalloc(sizeof(*amdtee), GFP_KERNEL);
470 if (!amdtee) {
471 rc = -ENOMEM;
472 goto err_kfree_drv_data;
473 }
474
475 pool = amdtee_config_shm();
476 if (IS_ERR(pool)) {
477 pr_err("shared pool configuration error\n");
478 rc = PTR_ERR(pool);
479 goto err_kfree_amdtee;
480 }
481
482 teedev = tee_device_alloc(&amdtee_desc, NULL, pool, amdtee);
483 if (IS_ERR(teedev)) {
484 rc = PTR_ERR(teedev);
485 goto err_free_pool;
486 }
487 amdtee->teedev = teedev;
488
489 rc = tee_device_register(amdtee->teedev);
490 if (rc)
491 goto err_device_unregister;
492
493 amdtee->pool = pool;
494
495 drv_data->amdtee = amdtee;
496
497 pr_info("amd-tee driver initialization successful\n");
498 return 0;
499
500 err_device_unregister:
501 tee_device_unregister(amdtee->teedev);
502
503 err_free_pool:
504 tee_shm_pool_free(pool);
505
506 err_kfree_amdtee:
507 kfree(amdtee);
508
509 err_kfree_drv_data:
510 kfree(drv_data);
511 drv_data = NULL;
512
513 pr_err("amd-tee driver initialization failed\n");
514 return rc;
515 }
516 module_init(amdtee_driver_init);
517
amdtee_driver_exit(void)518 static void __exit amdtee_driver_exit(void)
519 {
520 struct amdtee *amdtee;
521
522 if (!drv_data || !drv_data->amdtee)
523 return;
524
525 amdtee = drv_data->amdtee;
526
527 tee_device_unregister(amdtee->teedev);
528 tee_shm_pool_free(amdtee->pool);
529 }
530 module_exit(amdtee_driver_exit);
531
532 MODULE_AUTHOR(DRIVER_AUTHOR);
533 MODULE_DESCRIPTION("AMD-TEE driver");
534 MODULE_VERSION("1.0");
535 MODULE_LICENSE("Dual MIT/GPL");
536