Linux-libre 5.4.48-gnu
[librecmc/linux-libre.git] / drivers / tee / tee_core.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015-2016, Linaro Limited
4  */
5
6 #define pr_fmt(fmt) "%s: " fmt, __func__
7
8 #include <linux/cdev.h>
9 #include <linux/fs.h>
10 #include <linux/idr.h>
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/tee_drv.h>
14 #include <linux/uaccess.h>
15 #include "tee_private.h"
16
17 #define TEE_NUM_DEVICES 32
18
19 #define TEE_IOCTL_PARAM_SIZE(x) (sizeof(struct tee_param) * (x))
20
21 /*
22  * Unprivileged devices in the lower half range and privileged devices in
23  * the upper half range.
24  */
25 static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
26 static DEFINE_SPINLOCK(driver_lock);
27
28 static struct class *tee_class;
29 static dev_t tee_devt;
30
31 static struct tee_context *teedev_open(struct tee_device *teedev)
32 {
33         int rc;
34         struct tee_context *ctx;
35
36         if (!tee_device_get(teedev))
37                 return ERR_PTR(-EINVAL);
38
39         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
40         if (!ctx) {
41                 rc = -ENOMEM;
42                 goto err;
43         }
44
45         kref_init(&ctx->refcount);
46         ctx->teedev = teedev;
47         INIT_LIST_HEAD(&ctx->list_shm);
48         rc = teedev->desc->ops->open(ctx);
49         if (rc)
50                 goto err;
51
52         return ctx;
53 err:
54         kfree(ctx);
55         tee_device_put(teedev);
56         return ERR_PTR(rc);
57
58 }
59
60 void teedev_ctx_get(struct tee_context *ctx)
61 {
62         if (ctx->releasing)
63                 return;
64
65         kref_get(&ctx->refcount);
66 }
67
68 static void teedev_ctx_release(struct kref *ref)
69 {
70         struct tee_context *ctx = container_of(ref, struct tee_context,
71                                                refcount);
72         ctx->releasing = true;
73         ctx->teedev->desc->ops->release(ctx);
74         kfree(ctx);
75 }
76
77 void teedev_ctx_put(struct tee_context *ctx)
78 {
79         if (ctx->releasing)
80                 return;
81
82         kref_put(&ctx->refcount, teedev_ctx_release);
83 }
84
85 static void teedev_close_context(struct tee_context *ctx)
86 {
87         tee_device_put(ctx->teedev);
88         teedev_ctx_put(ctx);
89 }
90
91 static int tee_open(struct inode *inode, struct file *filp)
92 {
93         struct tee_context *ctx;
94
95         ctx = teedev_open(container_of(inode->i_cdev, struct tee_device, cdev));
96         if (IS_ERR(ctx))
97                 return PTR_ERR(ctx);
98
99         /*
100          * Default user-space behaviour is to wait for tee-supplicant
101          * if not present for any requests in this context.
102          */
103         ctx->supp_nowait = false;
104         filp->private_data = ctx;
105         return 0;
106 }
107
108 static int tee_release(struct inode *inode, struct file *filp)
109 {
110         teedev_close_context(filp->private_data);
111         return 0;
112 }
113
114 static int tee_ioctl_version(struct tee_context *ctx,
115                              struct tee_ioctl_version_data __user *uvers)
116 {
117         struct tee_ioctl_version_data vers;
118
119         ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
120
121         if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
122                 vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
123
124         if (copy_to_user(uvers, &vers, sizeof(vers)))
125                 return -EFAULT;
126
127         return 0;
128 }
129
130 static int tee_ioctl_shm_alloc(struct tee_context *ctx,
131                                struct tee_ioctl_shm_alloc_data __user *udata)
132 {
133         long ret;
134         struct tee_ioctl_shm_alloc_data data;
135         struct tee_shm *shm;
136
137         if (copy_from_user(&data, udata, sizeof(data)))
138                 return -EFAULT;
139
140         /* Currently no input flags are supported */
141         if (data.flags)
142                 return -EINVAL;
143
144         shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
145         if (IS_ERR(shm))
146                 return PTR_ERR(shm);
147
148         data.id = shm->id;
149         data.flags = shm->flags;
150         data.size = shm->size;
151
152         if (copy_to_user(udata, &data, sizeof(data)))
153                 ret = -EFAULT;
154         else
155                 ret = tee_shm_get_fd(shm);
156
157         /*
158          * When user space closes the file descriptor the shared memory
159          * should be freed or if tee_shm_get_fd() failed then it will
160          * be freed immediately.
161          */
162         tee_shm_put(shm);
163         return ret;
164 }
165
166 static int
167 tee_ioctl_shm_register(struct tee_context *ctx,
168                        struct tee_ioctl_shm_register_data __user *udata)
169 {
170         long ret;
171         struct tee_ioctl_shm_register_data data;
172         struct tee_shm *shm;
173
174         if (copy_from_user(&data, udata, sizeof(data)))
175                 return -EFAULT;
176
177         /* Currently no input flags are supported */
178         if (data.flags)
179                 return -EINVAL;
180
181         shm = tee_shm_register(ctx, data.addr, data.length,
182                                TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED);
183         if (IS_ERR(shm))
184                 return PTR_ERR(shm);
185
186         data.id = shm->id;
187         data.flags = shm->flags;
188         data.length = shm->size;
189
190         if (copy_to_user(udata, &data, sizeof(data)))
191                 ret = -EFAULT;
192         else
193                 ret = tee_shm_get_fd(shm);
194         /*
195          * When user space closes the file descriptor the shared memory
196          * should be freed or if tee_shm_get_fd() failed then it will
197          * be freed immediately.
198          */
199         tee_shm_put(shm);
200         return ret;
201 }
202
203 static int params_from_user(struct tee_context *ctx, struct tee_param *params,
204                             size_t num_params,
205                             struct tee_ioctl_param __user *uparams)
206 {
207         size_t n;
208
209         for (n = 0; n < num_params; n++) {
210                 struct tee_shm *shm;
211                 struct tee_ioctl_param ip;
212
213                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
214                         return -EFAULT;
215
216                 /* All unused attribute bits has to be zero */
217                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
218                         return -EINVAL;
219
220                 params[n].attr = ip.attr;
221                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
222                 case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
223                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
224                         break;
225                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
226                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
227                         params[n].u.value.a = ip.a;
228                         params[n].u.value.b = ip.b;
229                         params[n].u.value.c = ip.c;
230                         break;
231                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
232                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
233                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
234                         /*
235                          * If we fail to get a pointer to a shared memory
236                          * object (and increase the ref count) from an
237                          * identifier we return an error. All pointers that
238                          * has been added in params have an increased ref
239                          * count. It's the callers responibility to do
240                          * tee_shm_put() on all resolved pointers.
241                          */
242                         shm = tee_shm_get_from_id(ctx, ip.c);
243                         if (IS_ERR(shm))
244                                 return PTR_ERR(shm);
245
246                         /*
247                          * Ensure offset + size does not overflow offset
248                          * and does not overflow the size of the referred
249                          * shared memory object.
250                          */
251                         if ((ip.a + ip.b) < ip.a ||
252                             (ip.a + ip.b) > shm->size) {
253                                 tee_shm_put(shm);
254                                 return -EINVAL;
255                         }
256
257                         params[n].u.memref.shm_offs = ip.a;
258                         params[n].u.memref.size = ip.b;
259                         params[n].u.memref.shm = shm;
260                         break;
261                 default:
262                         /* Unknown attribute */
263                         return -EINVAL;
264                 }
265         }
266         return 0;
267 }
268
269 static int params_to_user(struct tee_ioctl_param __user *uparams,
270                           size_t num_params, struct tee_param *params)
271 {
272         size_t n;
273
274         for (n = 0; n < num_params; n++) {
275                 struct tee_ioctl_param __user *up = uparams + n;
276                 struct tee_param *p = params + n;
277
278                 switch (p->attr) {
279                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
280                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
281                         if (put_user(p->u.value.a, &up->a) ||
282                             put_user(p->u.value.b, &up->b) ||
283                             put_user(p->u.value.c, &up->c))
284                                 return -EFAULT;
285                         break;
286                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
287                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
288                         if (put_user((u64)p->u.memref.size, &up->b))
289                                 return -EFAULT;
290                 default:
291                         break;
292                 }
293         }
294         return 0;
295 }
296
297 static int tee_ioctl_open_session(struct tee_context *ctx,
298                                   struct tee_ioctl_buf_data __user *ubuf)
299 {
300         int rc;
301         size_t n;
302         struct tee_ioctl_buf_data buf;
303         struct tee_ioctl_open_session_arg __user *uarg;
304         struct tee_ioctl_open_session_arg arg;
305         struct tee_ioctl_param __user *uparams = NULL;
306         struct tee_param *params = NULL;
307         bool have_session = false;
308
309         if (!ctx->teedev->desc->ops->open_session)
310                 return -EINVAL;
311
312         if (copy_from_user(&buf, ubuf, sizeof(buf)))
313                 return -EFAULT;
314
315         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
316             buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
317                 return -EINVAL;
318
319         uarg = u64_to_user_ptr(buf.buf_ptr);
320         if (copy_from_user(&arg, uarg, sizeof(arg)))
321                 return -EFAULT;
322
323         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
324                 return -EINVAL;
325
326         if (arg.num_params) {
327                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
328                                  GFP_KERNEL);
329                 if (!params)
330                         return -ENOMEM;
331                 uparams = uarg->params;
332                 rc = params_from_user(ctx, params, arg.num_params, uparams);
333                 if (rc)
334                         goto out;
335         }
336
337         rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
338         if (rc)
339                 goto out;
340         have_session = true;
341
342         if (put_user(arg.session, &uarg->session) ||
343             put_user(arg.ret, &uarg->ret) ||
344             put_user(arg.ret_origin, &uarg->ret_origin)) {
345                 rc = -EFAULT;
346                 goto out;
347         }
348         rc = params_to_user(uparams, arg.num_params, params);
349 out:
350         /*
351          * If we've succeeded to open the session but failed to communicate
352          * it back to user space, close the session again to avoid leakage.
353          */
354         if (rc && have_session && ctx->teedev->desc->ops->close_session)
355                 ctx->teedev->desc->ops->close_session(ctx, arg.session);
356
357         if (params) {
358                 /* Decrease ref count for all valid shared memory pointers */
359                 for (n = 0; n < arg.num_params; n++)
360                         if (tee_param_is_memref(params + n) &&
361                             params[n].u.memref.shm)
362                                 tee_shm_put(params[n].u.memref.shm);
363                 kfree(params);
364         }
365
366         return rc;
367 }
368
369 static int tee_ioctl_invoke(struct tee_context *ctx,
370                             struct tee_ioctl_buf_data __user *ubuf)
371 {
372         int rc;
373         size_t n;
374         struct tee_ioctl_buf_data buf;
375         struct tee_ioctl_invoke_arg __user *uarg;
376         struct tee_ioctl_invoke_arg arg;
377         struct tee_ioctl_param __user *uparams = NULL;
378         struct tee_param *params = NULL;
379
380         if (!ctx->teedev->desc->ops->invoke_func)
381                 return -EINVAL;
382
383         if (copy_from_user(&buf, ubuf, sizeof(buf)))
384                 return -EFAULT;
385
386         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
387             buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
388                 return -EINVAL;
389
390         uarg = u64_to_user_ptr(buf.buf_ptr);
391         if (copy_from_user(&arg, uarg, sizeof(arg)))
392                 return -EFAULT;
393
394         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
395                 return -EINVAL;
396
397         if (arg.num_params) {
398                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
399                                  GFP_KERNEL);
400                 if (!params)
401                         return -ENOMEM;
402                 uparams = uarg->params;
403                 rc = params_from_user(ctx, params, arg.num_params, uparams);
404                 if (rc)
405                         goto out;
406         }
407
408         rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
409         if (rc)
410                 goto out;
411
412         if (put_user(arg.ret, &uarg->ret) ||
413             put_user(arg.ret_origin, &uarg->ret_origin)) {
414                 rc = -EFAULT;
415                 goto out;
416         }
417         rc = params_to_user(uparams, arg.num_params, params);
418 out:
419         if (params) {
420                 /* Decrease ref count for all valid shared memory pointers */
421                 for (n = 0; n < arg.num_params; n++)
422                         if (tee_param_is_memref(params + n) &&
423                             params[n].u.memref.shm)
424                                 tee_shm_put(params[n].u.memref.shm);
425                 kfree(params);
426         }
427         return rc;
428 }
429
430 static int tee_ioctl_cancel(struct tee_context *ctx,
431                             struct tee_ioctl_cancel_arg __user *uarg)
432 {
433         struct tee_ioctl_cancel_arg arg;
434
435         if (!ctx->teedev->desc->ops->cancel_req)
436                 return -EINVAL;
437
438         if (copy_from_user(&arg, uarg, sizeof(arg)))
439                 return -EFAULT;
440
441         return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
442                                                   arg.session);
443 }
444
445 static int
446 tee_ioctl_close_session(struct tee_context *ctx,
447                         struct tee_ioctl_close_session_arg __user *uarg)
448 {
449         struct tee_ioctl_close_session_arg arg;
450
451         if (!ctx->teedev->desc->ops->close_session)
452                 return -EINVAL;
453
454         if (copy_from_user(&arg, uarg, sizeof(arg)))
455                 return -EFAULT;
456
457         return ctx->teedev->desc->ops->close_session(ctx, arg.session);
458 }
459
460 static int params_to_supp(struct tee_context *ctx,
461                           struct tee_ioctl_param __user *uparams,
462                           size_t num_params, struct tee_param *params)
463 {
464         size_t n;
465
466         for (n = 0; n < num_params; n++) {
467                 struct tee_ioctl_param ip;
468                 struct tee_param *p = params + n;
469
470                 ip.attr = p->attr;
471                 switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
472                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
473                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
474                         ip.a = p->u.value.a;
475                         ip.b = p->u.value.b;
476                         ip.c = p->u.value.c;
477                         break;
478                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
479                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
480                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
481                         ip.b = p->u.memref.size;
482                         if (!p->u.memref.shm) {
483                                 ip.a = 0;
484                                 ip.c = (u64)-1; /* invalid shm id */
485                                 break;
486                         }
487                         ip.a = p->u.memref.shm_offs;
488                         ip.c = p->u.memref.shm->id;
489                         break;
490                 default:
491                         ip.a = 0;
492                         ip.b = 0;
493                         ip.c = 0;
494                         break;
495                 }
496
497                 if (copy_to_user(uparams + n, &ip, sizeof(ip)))
498                         return -EFAULT;
499         }
500
501         return 0;
502 }
503
504 static int tee_ioctl_supp_recv(struct tee_context *ctx,
505                                struct tee_ioctl_buf_data __user *ubuf)
506 {
507         int rc;
508         struct tee_ioctl_buf_data buf;
509         struct tee_iocl_supp_recv_arg __user *uarg;
510         struct tee_param *params;
511         u32 num_params;
512         u32 func;
513
514         if (!ctx->teedev->desc->ops->supp_recv)
515                 return -EINVAL;
516
517         if (copy_from_user(&buf, ubuf, sizeof(buf)))
518                 return -EFAULT;
519
520         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
521             buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
522                 return -EINVAL;
523
524         uarg = u64_to_user_ptr(buf.buf_ptr);
525         if (get_user(num_params, &uarg->num_params))
526                 return -EFAULT;
527
528         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
529                 return -EINVAL;
530
531         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
532         if (!params)
533                 return -ENOMEM;
534
535         rc = params_from_user(ctx, params, num_params, uarg->params);
536         if (rc)
537                 goto out;
538
539         rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
540         if (rc)
541                 goto out;
542
543         if (put_user(func, &uarg->func) ||
544             put_user(num_params, &uarg->num_params)) {
545                 rc = -EFAULT;
546                 goto out;
547         }
548
549         rc = params_to_supp(ctx, uarg->params, num_params, params);
550 out:
551         kfree(params);
552         return rc;
553 }
554
555 static int params_from_supp(struct tee_param *params, size_t num_params,
556                             struct tee_ioctl_param __user *uparams)
557 {
558         size_t n;
559
560         for (n = 0; n < num_params; n++) {
561                 struct tee_param *p = params + n;
562                 struct tee_ioctl_param ip;
563
564                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
565                         return -EFAULT;
566
567                 /* All unused attribute bits has to be zero */
568                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
569                         return -EINVAL;
570
571                 p->attr = ip.attr;
572                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
573                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
574                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
575                         /* Only out and in/out values can be updated */
576                         p->u.value.a = ip.a;
577                         p->u.value.b = ip.b;
578                         p->u.value.c = ip.c;
579                         break;
580                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
581                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
582                         /*
583                          * Only the size of the memref can be updated.
584                          * Since we don't have access to the original
585                          * parameters here, only store the supplied size.
586                          * The driver will copy the updated size into the
587                          * original parameters.
588                          */
589                         p->u.memref.shm = NULL;
590                         p->u.memref.shm_offs = 0;
591                         p->u.memref.size = ip.b;
592                         break;
593                 default:
594                         memset(&p->u, 0, sizeof(p->u));
595                         break;
596                 }
597         }
598         return 0;
599 }
600
601 static int tee_ioctl_supp_send(struct tee_context *ctx,
602                                struct tee_ioctl_buf_data __user *ubuf)
603 {
604         long rc;
605         struct tee_ioctl_buf_data buf;
606         struct tee_iocl_supp_send_arg __user *uarg;
607         struct tee_param *params;
608         u32 num_params;
609         u32 ret;
610
611         /* Not valid for this driver */
612         if (!ctx->teedev->desc->ops->supp_send)
613                 return -EINVAL;
614
615         if (copy_from_user(&buf, ubuf, sizeof(buf)))
616                 return -EFAULT;
617
618         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
619             buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
620                 return -EINVAL;
621
622         uarg = u64_to_user_ptr(buf.buf_ptr);
623         if (get_user(ret, &uarg->ret) ||
624             get_user(num_params, &uarg->num_params))
625                 return -EFAULT;
626
627         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
628                 return -EINVAL;
629
630         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
631         if (!params)
632                 return -ENOMEM;
633
634         rc = params_from_supp(params, num_params, uarg->params);
635         if (rc)
636                 goto out;
637
638         rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
639 out:
640         kfree(params);
641         return rc;
642 }
643
644 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
645 {
646         struct tee_context *ctx = filp->private_data;
647         void __user *uarg = (void __user *)arg;
648
649         switch (cmd) {
650         case TEE_IOC_VERSION:
651                 return tee_ioctl_version(ctx, uarg);
652         case TEE_IOC_SHM_ALLOC:
653                 return tee_ioctl_shm_alloc(ctx, uarg);
654         case TEE_IOC_SHM_REGISTER:
655                 return tee_ioctl_shm_register(ctx, uarg);
656         case TEE_IOC_OPEN_SESSION:
657                 return tee_ioctl_open_session(ctx, uarg);
658         case TEE_IOC_INVOKE:
659                 return tee_ioctl_invoke(ctx, uarg);
660         case TEE_IOC_CANCEL:
661                 return tee_ioctl_cancel(ctx, uarg);
662         case TEE_IOC_CLOSE_SESSION:
663                 return tee_ioctl_close_session(ctx, uarg);
664         case TEE_IOC_SUPPL_RECV:
665                 return tee_ioctl_supp_recv(ctx, uarg);
666         case TEE_IOC_SUPPL_SEND:
667                 return tee_ioctl_supp_send(ctx, uarg);
668         default:
669                 return -EINVAL;
670         }
671 }
672
673 static const struct file_operations tee_fops = {
674         .owner = THIS_MODULE,
675         .open = tee_open,
676         .release = tee_release,
677         .unlocked_ioctl = tee_ioctl,
678         .compat_ioctl = tee_ioctl,
679 };
680
681 static void tee_release_device(struct device *dev)
682 {
683         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
684
685         spin_lock(&driver_lock);
686         clear_bit(teedev->id, dev_mask);
687         spin_unlock(&driver_lock);
688         mutex_destroy(&teedev->mutex);
689         idr_destroy(&teedev->idr);
690         kfree(teedev);
691 }
692
693 /**
694  * tee_device_alloc() - Allocate a new struct tee_device instance
695  * @teedesc:    Descriptor for this driver
696  * @dev:        Parent device for this device
697  * @pool:       Shared memory pool, NULL if not used
698  * @driver_data: Private driver data for this device
699  *
700  * Allocates a new struct tee_device instance. The device is
701  * removed by tee_device_unregister().
702  *
703  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
704  */
705 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
706                                     struct device *dev,
707                                     struct tee_shm_pool *pool,
708                                     void *driver_data)
709 {
710         struct tee_device *teedev;
711         void *ret;
712         int rc, max_id;
713         int offs = 0;
714
715         if (!teedesc || !teedesc->name || !teedesc->ops ||
716             !teedesc->ops->get_version || !teedesc->ops->open ||
717             !teedesc->ops->release || !pool)
718                 return ERR_PTR(-EINVAL);
719
720         teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
721         if (!teedev) {
722                 ret = ERR_PTR(-ENOMEM);
723                 goto err;
724         }
725
726         max_id = TEE_NUM_DEVICES / 2;
727
728         if (teedesc->flags & TEE_DESC_PRIVILEGED) {
729                 offs = TEE_NUM_DEVICES / 2;
730                 max_id = TEE_NUM_DEVICES;
731         }
732
733         spin_lock(&driver_lock);
734         teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
735         if (teedev->id < max_id)
736                 set_bit(teedev->id, dev_mask);
737         spin_unlock(&driver_lock);
738
739         if (teedev->id >= max_id) {
740                 ret = ERR_PTR(-ENOMEM);
741                 goto err;
742         }
743
744         snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
745                  teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
746                  teedev->id - offs);
747
748         teedev->dev.class = tee_class;
749         teedev->dev.release = tee_release_device;
750         teedev->dev.parent = dev;
751
752         teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
753
754         rc = dev_set_name(&teedev->dev, "%s", teedev->name);
755         if (rc) {
756                 ret = ERR_PTR(rc);
757                 goto err_devt;
758         }
759
760         cdev_init(&teedev->cdev, &tee_fops);
761         teedev->cdev.owner = teedesc->owner;
762         teedev->cdev.kobj.parent = &teedev->dev.kobj;
763
764         dev_set_drvdata(&teedev->dev, driver_data);
765         device_initialize(&teedev->dev);
766
767         /* 1 as tee_device_unregister() does one final tee_device_put() */
768         teedev->num_users = 1;
769         init_completion(&teedev->c_no_users);
770         mutex_init(&teedev->mutex);
771         idr_init(&teedev->idr);
772
773         teedev->desc = teedesc;
774         teedev->pool = pool;
775
776         return teedev;
777 err_devt:
778         unregister_chrdev_region(teedev->dev.devt, 1);
779 err:
780         pr_err("could not register %s driver\n",
781                teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
782         if (teedev && teedev->id < TEE_NUM_DEVICES) {
783                 spin_lock(&driver_lock);
784                 clear_bit(teedev->id, dev_mask);
785                 spin_unlock(&driver_lock);
786         }
787         kfree(teedev);
788         return ret;
789 }
790 EXPORT_SYMBOL_GPL(tee_device_alloc);
791
792 static ssize_t implementation_id_show(struct device *dev,
793                                       struct device_attribute *attr, char *buf)
794 {
795         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
796         struct tee_ioctl_version_data vers;
797
798         teedev->desc->ops->get_version(teedev, &vers);
799         return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
800 }
801 static DEVICE_ATTR_RO(implementation_id);
802
803 static struct attribute *tee_dev_attrs[] = {
804         &dev_attr_implementation_id.attr,
805         NULL
806 };
807
808 static const struct attribute_group tee_dev_group = {
809         .attrs = tee_dev_attrs,
810 };
811
812 /**
813  * tee_device_register() - Registers a TEE device
814  * @teedev:     Device to register
815  *
816  * tee_device_unregister() need to be called to remove the @teedev if
817  * this function fails.
818  *
819  * @returns < 0 on failure
820  */
821 int tee_device_register(struct tee_device *teedev)
822 {
823         int rc;
824
825         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
826                 dev_err(&teedev->dev, "attempt to register twice\n");
827                 return -EINVAL;
828         }
829
830         rc = cdev_add(&teedev->cdev, teedev->dev.devt, 1);
831         if (rc) {
832                 dev_err(&teedev->dev,
833                         "unable to cdev_add() %s, major %d, minor %d, err=%d\n",
834                         teedev->name, MAJOR(teedev->dev.devt),
835                         MINOR(teedev->dev.devt), rc);
836                 return rc;
837         }
838
839         rc = device_add(&teedev->dev);
840         if (rc) {
841                 dev_err(&teedev->dev,
842                         "unable to device_add() %s, major %d, minor %d, err=%d\n",
843                         teedev->name, MAJOR(teedev->dev.devt),
844                         MINOR(teedev->dev.devt), rc);
845                 goto err_device_add;
846         }
847
848         rc = sysfs_create_group(&teedev->dev.kobj, &tee_dev_group);
849         if (rc) {
850                 dev_err(&teedev->dev,
851                         "failed to create sysfs attributes, err=%d\n", rc);
852                 goto err_sysfs_create_group;
853         }
854
855         teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
856         return 0;
857
858 err_sysfs_create_group:
859         device_del(&teedev->dev);
860 err_device_add:
861         cdev_del(&teedev->cdev);
862         return rc;
863 }
864 EXPORT_SYMBOL_GPL(tee_device_register);
865
866 void tee_device_put(struct tee_device *teedev)
867 {
868         mutex_lock(&teedev->mutex);
869         /* Shouldn't put in this state */
870         if (!WARN_ON(!teedev->desc)) {
871                 teedev->num_users--;
872                 if (!teedev->num_users) {
873                         teedev->desc = NULL;
874                         complete(&teedev->c_no_users);
875                 }
876         }
877         mutex_unlock(&teedev->mutex);
878 }
879
880 bool tee_device_get(struct tee_device *teedev)
881 {
882         mutex_lock(&teedev->mutex);
883         if (!teedev->desc) {
884                 mutex_unlock(&teedev->mutex);
885                 return false;
886         }
887         teedev->num_users++;
888         mutex_unlock(&teedev->mutex);
889         return true;
890 }
891
892 /**
893  * tee_device_unregister() - Removes a TEE device
894  * @teedev:     Device to unregister
895  *
896  * This function should be called to remove the @teedev even if
897  * tee_device_register() hasn't been called yet. Does nothing if
898  * @teedev is NULL.
899  */
900 void tee_device_unregister(struct tee_device *teedev)
901 {
902         if (!teedev)
903                 return;
904
905         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
906                 sysfs_remove_group(&teedev->dev.kobj, &tee_dev_group);
907                 cdev_del(&teedev->cdev);
908                 device_del(&teedev->dev);
909         }
910
911         tee_device_put(teedev);
912         wait_for_completion(&teedev->c_no_users);
913
914         /*
915          * No need to take a mutex any longer now since teedev->desc was
916          * set to NULL before teedev->c_no_users was completed.
917          */
918
919         teedev->pool = NULL;
920
921         put_device(&teedev->dev);
922 }
923 EXPORT_SYMBOL_GPL(tee_device_unregister);
924
925 /**
926  * tee_get_drvdata() - Return driver_data pointer
927  * @teedev:     Device containing the driver_data pointer
928  * @returns the driver_data pointer supplied to tee_register().
929  */
930 void *tee_get_drvdata(struct tee_device *teedev)
931 {
932         return dev_get_drvdata(&teedev->dev);
933 }
934 EXPORT_SYMBOL_GPL(tee_get_drvdata);
935
936 struct match_dev_data {
937         struct tee_ioctl_version_data *vers;
938         const void *data;
939         int (*match)(struct tee_ioctl_version_data *, const void *);
940 };
941
942 static int match_dev(struct device *dev, const void *data)
943 {
944         const struct match_dev_data *match_data = data;
945         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
946
947         teedev->desc->ops->get_version(teedev, match_data->vers);
948         return match_data->match(match_data->vers, match_data->data);
949 }
950
951 struct tee_context *
952 tee_client_open_context(struct tee_context *start,
953                         int (*match)(struct tee_ioctl_version_data *,
954                                      const void *),
955                         const void *data, struct tee_ioctl_version_data *vers)
956 {
957         struct device *dev = NULL;
958         struct device *put_dev = NULL;
959         struct tee_context *ctx = NULL;
960         struct tee_ioctl_version_data v;
961         struct match_dev_data match_data = { vers ? vers : &v, data, match };
962
963         if (start)
964                 dev = &start->teedev->dev;
965
966         do {
967                 dev = class_find_device(tee_class, dev, &match_data, match_dev);
968                 if (!dev) {
969                         ctx = ERR_PTR(-ENOENT);
970                         break;
971                 }
972
973                 put_device(put_dev);
974                 put_dev = dev;
975
976                 ctx = teedev_open(container_of(dev, struct tee_device, dev));
977         } while (IS_ERR(ctx) && PTR_ERR(ctx) != -ENOMEM);
978
979         put_device(put_dev);
980         /*
981          * Default behaviour for in kernel client is to not wait for
982          * tee-supplicant if not present for any requests in this context.
983          * Also this flag could be configured again before call to
984          * tee_client_open_session() if any in kernel client requires
985          * different behaviour.
986          */
987         if (!IS_ERR(ctx))
988                 ctx->supp_nowait = true;
989
990         return ctx;
991 }
992 EXPORT_SYMBOL_GPL(tee_client_open_context);
993
994 void tee_client_close_context(struct tee_context *ctx)
995 {
996         teedev_close_context(ctx);
997 }
998 EXPORT_SYMBOL_GPL(tee_client_close_context);
999
1000 void tee_client_get_version(struct tee_context *ctx,
1001                             struct tee_ioctl_version_data *vers)
1002 {
1003         ctx->teedev->desc->ops->get_version(ctx->teedev, vers);
1004 }
1005 EXPORT_SYMBOL_GPL(tee_client_get_version);
1006
1007 int tee_client_open_session(struct tee_context *ctx,
1008                             struct tee_ioctl_open_session_arg *arg,
1009                             struct tee_param *param)
1010 {
1011         if (!ctx->teedev->desc->ops->open_session)
1012                 return -EINVAL;
1013         return ctx->teedev->desc->ops->open_session(ctx, arg, param);
1014 }
1015 EXPORT_SYMBOL_GPL(tee_client_open_session);
1016
1017 int tee_client_close_session(struct tee_context *ctx, u32 session)
1018 {
1019         if (!ctx->teedev->desc->ops->close_session)
1020                 return -EINVAL;
1021         return ctx->teedev->desc->ops->close_session(ctx, session);
1022 }
1023 EXPORT_SYMBOL_GPL(tee_client_close_session);
1024
1025 int tee_client_invoke_func(struct tee_context *ctx,
1026                            struct tee_ioctl_invoke_arg *arg,
1027                            struct tee_param *param)
1028 {
1029         if (!ctx->teedev->desc->ops->invoke_func)
1030                 return -EINVAL;
1031         return ctx->teedev->desc->ops->invoke_func(ctx, arg, param);
1032 }
1033 EXPORT_SYMBOL_GPL(tee_client_invoke_func);
1034
1035 int tee_client_cancel_req(struct tee_context *ctx,
1036                           struct tee_ioctl_cancel_arg *arg)
1037 {
1038         if (!ctx->teedev->desc->ops->cancel_req)
1039                 return -EINVAL;
1040         return ctx->teedev->desc->ops->cancel_req(ctx, arg->cancel_id,
1041                                                   arg->session);
1042 }
1043
1044 static int tee_client_device_match(struct device *dev,
1045                                    struct device_driver *drv)
1046 {
1047         const struct tee_client_device_id *id_table;
1048         struct tee_client_device *tee_device;
1049
1050         id_table = to_tee_client_driver(drv)->id_table;
1051         tee_device = to_tee_client_device(dev);
1052
1053         while (!uuid_is_null(&id_table->uuid)) {
1054                 if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))
1055                         return 1;
1056                 id_table++;
1057         }
1058
1059         return 0;
1060 }
1061
1062 static int tee_client_device_uevent(struct device *dev,
1063                                     struct kobj_uevent_env *env)
1064 {
1065         uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;
1066
1067         return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
1068 }
1069
1070 struct bus_type tee_bus_type = {
1071         .name           = "tee",
1072         .match          = tee_client_device_match,
1073         .uevent         = tee_client_device_uevent,
1074 };
1075 EXPORT_SYMBOL_GPL(tee_bus_type);
1076
1077 static int __init tee_init(void)
1078 {
1079         int rc;
1080
1081         tee_class = class_create(THIS_MODULE, "tee");
1082         if (IS_ERR(tee_class)) {
1083                 pr_err("couldn't create class\n");
1084                 return PTR_ERR(tee_class);
1085         }
1086
1087         rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
1088         if (rc) {
1089                 pr_err("failed to allocate char dev region\n");
1090                 goto out_unreg_class;
1091         }
1092
1093         rc = bus_register(&tee_bus_type);
1094         if (rc) {
1095                 pr_err("failed to register tee bus\n");
1096                 goto out_unreg_chrdev;
1097         }
1098
1099         return 0;
1100
1101 out_unreg_chrdev:
1102         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1103 out_unreg_class:
1104         class_destroy(tee_class);
1105         tee_class = NULL;
1106
1107         return rc;
1108 }
1109
1110 static void __exit tee_exit(void)
1111 {
1112         bus_unregister(&tee_bus_type);
1113         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
1114         class_destroy(tee_class);
1115         tee_class = NULL;
1116 }
1117
1118 subsys_initcall(tee_init);
1119 module_exit(tee_exit);
1120
1121 MODULE_AUTHOR("Linaro");
1122 MODULE_DESCRIPTION("TEE Driver");
1123 MODULE_VERSION("1.0");
1124 MODULE_LICENSE("GPL v2");