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
220 /* mutex must be held by caller */
destroy_session(struct kref * ref)221 static void destroy_session(struct kref *ref)
222 {
223 struct amdtee_session *sess = container_of(ref, struct amdtee_session,
224 refcount);
225
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 /* Open session with loaded TA */
271 handle_open_session(arg, &session_info, param);
272 if (arg->ret != TEEC_SUCCESS) {
273 pr_err("open_session failed %d\n", arg->ret);
274 handle_unload_ta(ta_handle);
275 kref_put_mutex(&sess->refcount, destroy_session,
276 &session_list_mutex);
277 goto out;
278 }
279
280 /* Find an empty session index for the given TA */
281 spin_lock(&sess->lock);
282 i = find_first_zero_bit(sess->sess_mask, TEE_NUM_SESSIONS);
283 if (i < TEE_NUM_SESSIONS) {
284 sess->session_info[i] = session_info;
285 set_session_id(ta_handle, i, &arg->session);
286 set_bit(i, sess->sess_mask);
287 }
288 spin_unlock(&sess->lock);
289
290 if (i >= TEE_NUM_SESSIONS) {
291 pr_err("reached maximum session count %d\n", TEE_NUM_SESSIONS);
292 handle_close_session(ta_handle, session_info);
293 handle_unload_ta(ta_handle);
294 kref_put_mutex(&sess->refcount, destroy_session,
295 &session_list_mutex);
296 rc = -ENOMEM;
297 goto out;
298 }
299
300 out:
301 free_pages((u64)ta, get_order(ta_size));
302 return rc;
303 }
304
amdtee_close_session(struct tee_context * ctx,u32 session)305 int amdtee_close_session(struct tee_context *ctx, u32 session)
306 {
307 struct amdtee_context_data *ctxdata = ctx->data;
308 u32 i, ta_handle, session_info;
309 struct amdtee_session *sess;
310
311 pr_debug("%s: sid = 0x%x\n", __func__, session);
312
313 /*
314 * Check that the session is valid and clear the session
315 * usage bit
316 */
317 mutex_lock(&session_list_mutex);
318 sess = find_session(ctxdata, session);
319 if (sess) {
320 ta_handle = get_ta_handle(session);
321 i = get_session_index(session);
322 session_info = sess->session_info[i];
323 spin_lock(&sess->lock);
324 clear_bit(i, sess->sess_mask);
325 spin_unlock(&sess->lock);
326 }
327 mutex_unlock(&session_list_mutex);
328
329 if (!sess)
330 return -EINVAL;
331
332 /* Close the session */
333 handle_close_session(ta_handle, session_info);
334 handle_unload_ta(ta_handle);
335
336 kref_put_mutex(&sess->refcount, destroy_session, &session_list_mutex);
337
338 return 0;
339 }
340
amdtee_map_shmem(struct tee_shm * shm)341 int amdtee_map_shmem(struct tee_shm *shm)
342 {
343 struct amdtee_context_data *ctxdata;
344 struct amdtee_shm_data *shmnode;
345 struct shmem_desc shmem;
346 int rc, count;
347 u32 buf_id;
348
349 if (!shm)
350 return -EINVAL;
351
352 shmnode = kmalloc(sizeof(*shmnode), GFP_KERNEL);
353 if (!shmnode)
354 return -ENOMEM;
355
356 count = 1;
357 shmem.kaddr = shm->kaddr;
358 shmem.size = shm->size;
359
360 /*
361 * Send a MAP command to TEE and get the corresponding
362 * buffer Id
363 */
364 rc = handle_map_shmem(count, &shmem, &buf_id);
365 if (rc) {
366 pr_err("map_shmem failed: ret = %d\n", rc);
367 kfree(shmnode);
368 return rc;
369 }
370
371 shmnode->kaddr = shm->kaddr;
372 shmnode->buf_id = buf_id;
373 ctxdata = shm->ctx->data;
374 mutex_lock(&ctxdata->shm_mutex);
375 list_add(&shmnode->shm_node, &ctxdata->shm_list);
376 mutex_unlock(&ctxdata->shm_mutex);
377
378 pr_debug("buf_id :[%x] kaddr[%p]\n", shmnode->buf_id, shmnode->kaddr);
379
380 return 0;
381 }
382
amdtee_unmap_shmem(struct tee_shm * shm)383 void amdtee_unmap_shmem(struct tee_shm *shm)
384 {
385 struct amdtee_context_data *ctxdata;
386 struct amdtee_shm_data *shmnode;
387 u32 buf_id;
388
389 if (!shm)
390 return;
391
392 buf_id = get_buffer_id(shm);
393 /* Unmap the shared memory from TEE */
394 handle_unmap_shmem(buf_id);
395
396 ctxdata = shm->ctx->data;
397 mutex_lock(&ctxdata->shm_mutex);
398 list_for_each_entry(shmnode, &ctxdata->shm_list, shm_node)
399 if (buf_id == shmnode->buf_id) {
400 list_del(&shmnode->shm_node);
401 kfree(shmnode);
402 break;
403 }
404 mutex_unlock(&ctxdata->shm_mutex);
405 }
406
amdtee_invoke_func(struct tee_context * ctx,struct tee_ioctl_invoke_arg * arg,struct tee_param * param)407 int amdtee_invoke_func(struct tee_context *ctx,
408 struct tee_ioctl_invoke_arg *arg,
409 struct tee_param *param)
410 {
411 struct amdtee_context_data *ctxdata = ctx->data;
412 struct amdtee_session *sess;
413 u32 i, session_info;
414
415 /* Check that the session is valid */
416 mutex_lock(&session_list_mutex);
417 sess = find_session(ctxdata, arg->session);
418 if (sess) {
419 i = get_session_index(arg->session);
420 session_info = sess->session_info[i];
421 }
422 mutex_unlock(&session_list_mutex);
423
424 if (!sess)
425 return -EINVAL;
426
427 handle_invoke_cmd(arg, session_info, param);
428
429 return 0;
430 }
431
amdtee_cancel_req(struct tee_context * ctx,u32 cancel_id,u32 session)432 int amdtee_cancel_req(struct tee_context *ctx, u32 cancel_id, u32 session)
433 {
434 return -EINVAL;
435 }
436
437 static const struct tee_driver_ops amdtee_ops = {
438 .get_version = amdtee_get_version,
439 .open = amdtee_open,
440 .release = amdtee_release,
441 .open_session = amdtee_open_session,
442 .close_session = amdtee_close_session,
443 .invoke_func = amdtee_invoke_func,
444 .cancel_req = amdtee_cancel_req,
445 };
446
447 static const struct tee_desc amdtee_desc = {
448 .name = DRIVER_NAME "-clnt",
449 .ops = &amdtee_ops,
450 .owner = THIS_MODULE,
451 };
452
amdtee_driver_init(void)453 static int __init amdtee_driver_init(void)
454 {
455 struct tee_device *teedev;
456 struct tee_shm_pool *pool;
457 struct amdtee *amdtee;
458 int rc;
459
460 rc = psp_check_tee_status();
461 if (rc) {
462 pr_err("amd-tee driver: tee not present\n");
463 return rc;
464 }
465
466 drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
467 if (!drv_data)
468 return -ENOMEM;
469
470 amdtee = kzalloc(sizeof(*amdtee), GFP_KERNEL);
471 if (!amdtee) {
472 rc = -ENOMEM;
473 goto err_kfree_drv_data;
474 }
475
476 pool = amdtee_config_shm();
477 if (IS_ERR(pool)) {
478 pr_err("shared pool configuration error\n");
479 rc = PTR_ERR(pool);
480 goto err_kfree_amdtee;
481 }
482
483 teedev = tee_device_alloc(&amdtee_desc, NULL, pool, amdtee);
484 if (IS_ERR(teedev)) {
485 rc = PTR_ERR(teedev);
486 goto err_free_pool;
487 }
488 amdtee->teedev = teedev;
489
490 rc = tee_device_register(amdtee->teedev);
491 if (rc)
492 goto err_device_unregister;
493
494 amdtee->pool = pool;
495
496 drv_data->amdtee = amdtee;
497
498 pr_info("amd-tee driver initialization successful\n");
499 return 0;
500
501 err_device_unregister:
502 tee_device_unregister(amdtee->teedev);
503
504 err_free_pool:
505 tee_shm_pool_free(pool);
506
507 err_kfree_amdtee:
508 kfree(amdtee);
509
510 err_kfree_drv_data:
511 kfree(drv_data);
512 drv_data = NULL;
513
514 pr_err("amd-tee driver initialization failed\n");
515 return rc;
516 }
517 module_init(amdtee_driver_init);
518
amdtee_driver_exit(void)519 static void __exit amdtee_driver_exit(void)
520 {
521 struct amdtee *amdtee;
522
523 if (!drv_data || !drv_data->amdtee)
524 return;
525
526 amdtee = drv_data->amdtee;
527
528 tee_device_unregister(amdtee->teedev);
529 tee_shm_pool_free(amdtee->pool);
530 }
531 module_exit(amdtee_driver_exit);
532
533 MODULE_AUTHOR(DRIVER_AUTHOR);
534 MODULE_DESCRIPTION("AMD-TEE driver");
535 MODULE_VERSION("1.0");
536 MODULE_LICENSE("Dual MIT/GPL");
537