drivers/tee/tee_core.c

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