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                         params[n].u.memref.shm_offs = ip.a;
 242                         params[n].u.memref.size = ip.b;
 243                         params[n].u.memref.shm = shm;
 244                         break;
 245                 default:
 246                         /* Unknown attribute */
 247                         return -EINVAL;
 248                 }
 249         }
 250         return 0;
 251 }
 252
 253 static int params_to_user(struct tee_ioctl_param __user *uparams,
 254                           size_t num_params, struct tee_param *params)
 255 {
 256         size_t n;
 257
 258         for (n = 0; n < num_params; n++) {
 259                 struct tee_ioctl_param __user *up = uparams + n;
 260                 struct tee_param *p = params + n;
 261
 262                 switch (p->attr) {
 263                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 264                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 265                         if (put_user(p->u.value.a, &up->a) ||
 266                             put_user(p->u.value.b, &up->b) ||
 267                             put_user(p->u.value.c, &up->c))
 268                                 return -EFAULT;
 269                         break;
 270                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 271                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 272                         if (put_user((u64)p->u.memref.size, &up->b))
 273                                 return -EFAULT;
 274                 default:
 275                         break;
 276                 }
 277         }
 278         return 0;
 279 }
 280
 281 static int tee_ioctl_open_session(struct tee_context *ctx,
 282                                   struct tee_ioctl_buf_data __user *ubuf)
 283 {
 284         int rc;
 285         size_t n;
 286         struct tee_ioctl_buf_data buf;
 287         struct tee_ioctl_open_session_arg __user *uarg;
 288         struct tee_ioctl_open_session_arg arg;
 289         struct tee_ioctl_param __user *uparams = NULL;
 290         struct tee_param *params = NULL;
 291         bool have_session = false;
 292
 293         if (!ctx->teedev->desc->ops->open_session)
 294                 return -EINVAL;
 295
 296         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 297                 return -EFAULT;
 298
 299         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 300             buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
 301                 return -EINVAL;
 302
 303         uarg = u64_to_user_ptr(buf.buf_ptr);
 304         if (copy_from_user(&arg, uarg, sizeof(arg)))
 305                 return -EFAULT;
 306
 307         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 308                 return -EINVAL;
 309
 310         if (arg.num_params) {
 311                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 312                                  GFP_KERNEL);
 313                 if (!params)
 314                         return -ENOMEM;
 315                 uparams = uarg->params;
 316                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 317                 if (rc)
 318                         goto out;
 319         }
 320
 321         rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
 322         if (rc)
 323                 goto out;
 324         have_session = true;
 325
 326         if (put_user(arg.session, &uarg->session) ||
 327             put_user(arg.ret, &uarg->ret) ||
 328             put_user(arg.ret_origin, &uarg->ret_origin)) {
 329                 rc = -EFAULT;
 330                 goto out;
 331         }
 332         rc = params_to_user(uparams, arg.num_params, params);
 333 out:
 334         /*
 335          * If we've succeeded to open the session but failed to communicate
 336          * it back to user space, close the session again to avoid leakage.
 337          */
 338         if (rc && have_session && ctx->teedev->desc->ops->close_session)
 339                 ctx->teedev->desc->ops->close_session(ctx, arg.session);
 340
 341         if (params) {
 342                 /* Decrease ref count for all valid shared memory pointers */
 343                 for (n = 0; n < arg.num_params; n++)
 344                         if (tee_param_is_memref(params + n) &&
 345                             params[n].u.memref.shm)
 346                                 tee_shm_put(params[n].u.memref.shm);
 347                 kfree(params);
 348         }
 349
 350         return rc;
 351 }
 352
 353 static int tee_ioctl_invoke(struct tee_context *ctx,
 354                             struct tee_ioctl_buf_data __user *ubuf)
 355 {
 356         int rc;
 357         size_t n;
 358         struct tee_ioctl_buf_data buf;
 359         struct tee_ioctl_invoke_arg __user *uarg;
 360         struct tee_ioctl_invoke_arg arg;
 361         struct tee_ioctl_param __user *uparams = NULL;
 362         struct tee_param *params = NULL;
 363
 364         if (!ctx->teedev->desc->ops->invoke_func)
 365                 return -EINVAL;
 366
 367         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 368                 return -EFAULT;
 369
 370         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 371             buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
 372                 return -EINVAL;
 373
 374         uarg = u64_to_user_ptr(buf.buf_ptr);
 375         if (copy_from_user(&arg, uarg, sizeof(arg)))
 376                 return -EFAULT;
 377
 378         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 379                 return -EINVAL;
 380
 381         if (arg.num_params) {
 382                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 383                                  GFP_KERNEL);
 384                 if (!params)
 385                         return -ENOMEM;
 386                 uparams = uarg->params;
 387                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 388                 if (rc)
 389                         goto out;
 390         }
 391
 392         rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
 393         if (rc)
 394                 goto out;
 395
 396         if (put_user(arg.ret, &uarg->ret) ||
 397             put_user(arg.ret_origin, &uarg->ret_origin)) {
 398                 rc = -EFAULT;
 399                 goto out;
 400         }
 401         rc = params_to_user(uparams, arg.num_params, params);
 402 out:
 403         if (params) {
 404                 /* Decrease ref count for all valid shared memory pointers */
 405                 for (n = 0; n < arg.num_params; n++)
 406                         if (tee_param_is_memref(params + n) &&
 407                             params[n].u.memref.shm)
 408                                 tee_shm_put(params[n].u.memref.shm);
 409                 kfree(params);
 410         }
 411         return rc;
 412 }
 413
 414 static int tee_ioctl_cancel(struct tee_context *ctx,
 415                             struct tee_ioctl_cancel_arg __user *uarg)
 416 {
 417         struct tee_ioctl_cancel_arg arg;
 418
 419         if (!ctx->teedev->desc->ops->cancel_req)
 420                 return -EINVAL;
 421
 422         if (copy_from_user(&arg, uarg, sizeof(arg)))
 423                 return -EFAULT;
 424
 425         return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
 426                                                   arg.session);
 427 }
 428
 429 static int
 430 tee_ioctl_close_session(struct tee_context *ctx,
 431                         struct tee_ioctl_close_session_arg __user *uarg)
 432 {
 433         struct tee_ioctl_close_session_arg arg;
 434
 435         if (!ctx->teedev->desc->ops->close_session)
 436                 return -EINVAL;
 437
 438         if (copy_from_user(&arg, uarg, sizeof(arg)))
 439                 return -EFAULT;
 440
 441         return ctx->teedev->desc->ops->close_session(ctx, arg.session);
 442 }
 443
 444 static int params_to_supp(struct tee_context *ctx,
 445                           struct tee_ioctl_param __user *uparams,
 446                           size_t num_params, struct tee_param *params)
 447 {
 448         size_t n;
 449
 450         for (n = 0; n < num_params; n++) {
 451                 struct tee_ioctl_param ip;
 452                 struct tee_param *p = params + n;
 453
 454                 ip.attr = p->attr;
 455                 switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 456                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 457                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 458                         ip.a = p->u.value.a;
 459                         ip.b = p->u.value.b;
 460                         ip.c = p->u.value.c;
 461                         break;
 462                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 463                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 464                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 465                         ip.b = p->u.memref.size;
 466                         if (!p->u.memref.shm) {
 467                                 ip.a = 0;
 468                                 ip.c = (u64)-1; /* invalid shm id */
 469                                 break;
 470                         }
 471                         ip.a = p->u.memref.shm_offs;
 472                         ip.c = p->u.memref.shm->id;
 473                         break;
 474                 default:
 475                         ip.a = 0;
 476                         ip.b = 0;
 477                         ip.c = 0;
 478                         break;
 479                 }
 480
 481                 if (copy_to_user(uparams + n, &ip, sizeof(ip)))
 482                         return -EFAULT;
 483         }
 484
 485         return 0;
 486 }
 487
 488 static int tee_ioctl_supp_recv(struct tee_context *ctx,
 489                                struct tee_ioctl_buf_data __user *ubuf)
 490 {
 491         int rc;
 492         struct tee_ioctl_buf_data buf;
 493         struct tee_iocl_supp_recv_arg __user *uarg;
 494         struct tee_param *params;
 495         u32 num_params;
 496         u32 func;
 497
 498         if (!ctx->teedev->desc->ops->supp_recv)
 499                 return -EINVAL;
 500
 501         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 502                 return -EFAULT;
 503
 504         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 505             buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
 506                 return -EINVAL;
 507
 508         uarg = u64_to_user_ptr(buf.buf_ptr);
 509         if (get_user(num_params, &uarg->num_params))
 510                 return -EFAULT;
 511
 512         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
 513                 return -EINVAL;
 514
 515         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 516         if (!params)
 517                 return -ENOMEM;
 518
 519         rc = params_from_user(ctx, params, num_params, uarg->params);
 520         if (rc)
 521                 goto out;
 522
 523         rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
 524         if (rc)
 525                 goto out;
 526
 527         if (put_user(func, &uarg->func) ||
 528             put_user(num_params, &uarg->num_params)) {
 529                 rc = -EFAULT;
 530                 goto out;
 531         }
 532
 533         rc = params_to_supp(ctx, uarg->params, num_params, params);
 534 out:
 535         kfree(params);
 536         return rc;
 537 }
 538
 539 static int params_from_supp(struct tee_param *params, size_t num_params,
 540                             struct tee_ioctl_param __user *uparams)
 541 {
 542         size_t n;
 543
 544         for (n = 0; n < num_params; n++) {
 545                 struct tee_param *p = params + n;
 546                 struct tee_ioctl_param ip;
 547
 548                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 549                         return -EFAULT;
 550
 551                 /* All unused attribute bits has to be zero */
 552                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 553                         return -EINVAL;
 554
 555                 p->attr = ip.attr;
 556                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 557                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 558                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 559                         /* Only out and in/out values can be updated */
 560                         p->u.value.a = ip.a;
 561                         p->u.value.b = ip.b;
 562                         p->u.value.c = ip.c;
 563                         break;
 564                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 565                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 566                         /*
 567                          * Only the size of the memref can be updated.
 568                          * Since we don't have access to the original
 569                          * parameters here, only store the supplied size.
 570                          * The driver will copy the updated size into the
 571                          * original parameters.
 572                          */
 573                         p->u.memref.shm = NULL;
 574                         p->u.memref.shm_offs = 0;
 575                         p->u.memref.size = ip.b;
 576                         break;
 577                 default:
 578                         memset(&p->u, 0, sizeof(p->u));
 579                         break;
 580                 }
 581         }
 582         return 0;
 583 }
 584
 585 static int tee_ioctl_supp_send(struct tee_context *ctx,
 586                                struct tee_ioctl_buf_data __user *ubuf)
 587 {
 588         long rc;
 589         struct tee_ioctl_buf_data buf;
 590         struct tee_iocl_supp_send_arg __user *uarg;
 591         struct tee_param *params;
 592         u32 num_params;
 593         u32 ret;
 594
 595         /* Not valid for this driver */
 596         if (!ctx->teedev->desc->ops->supp_send)
 597                 return -EINVAL;
 598
 599         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 600                 return -EFAULT;
 601
 602         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 603             buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
 604                 return -EINVAL;
 605
 606         uarg = u64_to_user_ptr(buf.buf_ptr);
 607         if (get_user(ret, &uarg->ret) ||
 608             get_user(num_params, &uarg->num_params))
 609                 return -EFAULT;
 610
 611         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
 612                 return -EINVAL;
 613
 614         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 615         if (!params)
 616                 return -ENOMEM;
 617
 618         rc = params_from_supp(params, num_params, uarg->params);
 619         if (rc)
 620                 goto out;
 621
 622         rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
 623 out:
 624         kfree(params);
 625         return rc;
 626 }
 627
 628 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 629 {
 630         struct tee_context *ctx = filp->private_data;
 631         void __user *uarg = (void __user *)arg;
 632
 633         switch (cmd) {
 634         case TEE_IOC_VERSION:
 635                 return tee_ioctl_version(ctx, uarg);
 636         case TEE_IOC_SHM_ALLOC:
 637                 return tee_ioctl_shm_alloc(ctx, uarg);
 638         case TEE_IOC_SHM_REGISTER:
 639                 return tee_ioctl_shm_register(ctx, uarg);
 640         case TEE_IOC_OPEN_SESSION:
 641                 return tee_ioctl_open_session(ctx, uarg);
 642         case TEE_IOC_INVOKE:
 643                 return tee_ioctl_invoke(ctx, uarg);
 644         case TEE_IOC_CANCEL:
 645                 return tee_ioctl_cancel(ctx, uarg);
 646         case TEE_IOC_CLOSE_SESSION:
 647                 return tee_ioctl_close_session(ctx, uarg);
 648         case TEE_IOC_SUPPL_RECV:
 649                 return tee_ioctl_supp_recv(ctx, uarg);
 650         case TEE_IOC_SUPPL_SEND:
 651                 return tee_ioctl_supp_send(ctx, uarg);
 652         default:
 653                 return -EINVAL;
 654         }
 655 }
 656
 657 static const struct file_operations tee_fops = {
 658         .owner = THIS_MODULE,
 659         .open = tee_open,
 660         .release = tee_release,
 661         .unlocked_ioctl = tee_ioctl,
 662         .compat_ioctl = tee_ioctl,
 663 };
 664
 665 static void tee_release_device(struct device *dev)
 666 {
 667         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 668
 669         spin_lock(&driver_lock);
 670         clear_bit(teedev->id, dev_mask);
 671         spin_unlock(&driver_lock);
 672         mutex_destroy(&teedev->mutex);
 673         idr_destroy(&teedev->idr);
 674         kfree(teedev);
 675 }
 676
 677 /**
 678  * tee_device_alloc() - Allocate a new struct tee_device instance
 679  * @teedesc:    Descriptor for this driver
 680  * @dev:        Parent device for this device
 681  * @pool:       Shared memory pool, NULL if not used
 682  * @driver_data: Private driver data for this device
 683  *
 684  * Allocates a new struct tee_device instance. The device is
 685  * removed by tee_device_unregister().
 686  *
 687  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
 688  */
 689 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 690                                     struct device *dev,
 691                                     struct tee_shm_pool *pool,
 692                                     void *driver_data)
 693 {
 694         struct tee_device *teedev;
 695         void *ret;
 696         int rc, max_id;
 697         int offs = 0;
 698
 699         if (!teedesc || !teedesc->name || !teedesc->ops ||
 700             !teedesc->ops->get_version || !teedesc->ops->open ||
 701             !teedesc->ops->release || !pool)
 702                 return ERR_PTR(-EINVAL);
 703
 704         teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
 705         if (!teedev) {
 706                 ret = ERR_PTR(-ENOMEM);
 707                 goto err;
 708         }
 709
 710         max_id = TEE_NUM_DEVICES / 2;
 711
 712         if (teedesc->flags & TEE_DESC_PRIVILEGED) {
 713                 offs = TEE_NUM_DEVICES / 2;
 714                 max_id = TEE_NUM_DEVICES;
 715         }
 716
 717         spin_lock(&driver_lock);
 718         teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
 719         if (teedev->id < max_id)
 720                 set_bit(teedev->id, dev_mask);
 721         spin_unlock(&driver_lock);
 722
 723         if (teedev->id >= max_id) {
 724                 ret = ERR_PTR(-ENOMEM);
 725                 goto err;
 726         }
 727
 728         snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
 729                  teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
 730                  teedev->id - offs);
 731
 732         teedev->dev.class = tee_class;
 733         teedev->dev.release = tee_release_device;
 734         teedev->dev.parent = dev;
 735
 736         teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
 737
 738         rc = dev_set_name(&teedev->dev, "%s", teedev->name);
 739         if (rc) {
 740                 ret = ERR_PTR(rc);
 741                 goto err_devt;
 742         }
 743
 744         cdev_init(&teedev->cdev, &tee_fops);
 745         teedev->cdev.owner = teedesc->owner;
 746         teedev->cdev.kobj.parent = &teedev->dev.kobj;
 747
 748         dev_set_drvdata(&teedev->dev, driver_data);
 749         device_initialize(&teedev->dev);
 750
 751         /* 1 as tee_device_unregister() does one final tee_device_put() */
 752         teedev->num_users = 1;
 753         init_completion(&teedev->c_no_users);
 754         mutex_init(&teedev->mutex);
 755         idr_init(&teedev->idr);
 756
 757         teedev->desc = teedesc;
 758         teedev->pool = pool;
 759
 760         return teedev;
 761 err_devt:
 762         unregister_chrdev_region(teedev->dev.devt, 1);
 763 err:
 764         pr_err("could not register %s driver\n",
 765                teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
 766         if (teedev && teedev->id < TEE_NUM_DEVICES) {
 767                 spin_lock(&driver_lock);
 768                 clear_bit(teedev->id, dev_mask);
 769                 spin_unlock(&driver_lock);
 770         }
 771         kfree(teedev);
 772         return ret;
 773 }
 774 EXPORT_SYMBOL_GPL(tee_device_alloc);
 775
 776 static ssize_t implementation_id_show(struct device *dev,
 777                                       struct device_attribute *attr, char *buf)
 778 {
 779         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 780         struct tee_ioctl_version_data vers;
 781
 782         teedev->desc->ops->get_version(teedev, &vers);
 783         return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
 784 }
 785 static DEVICE_ATTR_RO(implementation_id);
 786
 787 static struct attribute *tee_dev_attrs[] = {
 788         &dev_attr_implementation_id.attr,
 789         NULL
 790 };
 791
 792 static const struct attribute_group tee_dev_group = {
 793         .attrs = tee_dev_attrs,
 794 };
 795
 796 /**
 797  * tee_device_register() - Registers a TEE device
 798  * @teedev:     Device to register
 799  *
 800  * tee_device_unregister() need to be called to remove the @teedev if
 801  * this function fails.
 802  *
 803  * @returns < 0 on failure
 804  */
 805 int tee_device_register(struct tee_device *teedev)
 806 {
 807         int rc;
 808
 809         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
 810                 dev_err(&teedev->dev, "attempt to register twice\n");
 811                 return -EINVAL;
 812         }
 813
 814         rc = cdev_add(&teedev->cdev, teedev->dev.devt, 1);
 815         if (rc) {
 816                 dev_err(&teedev->dev,
 817                         "unable to cdev_add() %s, major %d, minor %d, err=%d\n",
 818                         teedev->name, MAJOR(teedev->dev.devt),
 819                         MINOR(teedev->dev.devt), rc);
 820                 return rc;
 821         }
 822
 823         rc = device_add(&teedev->dev);
 824         if (rc) {
 825                 dev_err(&teedev->dev,
 826                         "unable to device_add() %s, major %d, minor %d, err=%d\n",
 827                         teedev->name, MAJOR(teedev->dev.devt),
 828                         MINOR(teedev->dev.devt), rc);
 829                 goto err_device_add;
 830         }
 831
 832         rc = sysfs_create_group(&teedev->dev.kobj, &tee_dev_group);
 833         if (rc) {
 834                 dev_err(&teedev->dev,
 835                         "failed to create sysfs attributes, err=%d\n", rc);
 836                 goto err_sysfs_create_group;
 837         }
 838
 839         teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
 840         return 0;
 841
 842 err_sysfs_create_group:
 843         device_del(&teedev->dev);
 844 err_device_add:
 845         cdev_del(&teedev->cdev);
 846         return rc;
 847 }
 848 EXPORT_SYMBOL_GPL(tee_device_register);
 849
 850 void tee_device_put(struct tee_device *teedev)
 851 {
 852         mutex_lock(&teedev->mutex);
 853         /* Shouldn't put in this state */
 854         if (!WARN_ON(!teedev->desc)) {
 855                 teedev->num_users--;
 856                 if (!teedev->num_users) {
 857                         teedev->desc = NULL;
 858                         complete(&teedev->c_no_users);
 859                 }
 860         }
 861         mutex_unlock(&teedev->mutex);
 862 }
 863
 864 bool tee_device_get(struct tee_device *teedev)
 865 {
 866         mutex_lock(&teedev->mutex);
 867         if (!teedev->desc) {
 868                 mutex_unlock(&teedev->mutex);
 869                 return false;
 870         }
 871         teedev->num_users++;
 872         mutex_unlock(&teedev->mutex);
 873         return true;
 874 }
 875
 876 /**
 877  * tee_device_unregister() - Removes a TEE device
 878  * @teedev:     Device to unregister
 879  *
 880  * This function should be called to remove the @teedev even if
 881  * tee_device_register() hasn't been called yet. Does nothing if
 882  * @teedev is NULL.
 883  */
 884 void tee_device_unregister(struct tee_device *teedev)
 885 {
 886         if (!teedev)
 887                 return;
 888
 889         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
 890                 sysfs_remove_group(&teedev->dev.kobj, &tee_dev_group);
 891                 cdev_del(&teedev->cdev);
 892                 device_del(&teedev->dev);
 893         }
 894
 895         tee_device_put(teedev);
 896         wait_for_completion(&teedev->c_no_users);
 897
 898         /*
 899          * No need to take a mutex any longer now since teedev->desc was
 900          * set to NULL before teedev->c_no_users was completed.
 901          */
 902
 903         teedev->pool = NULL;
 904
 905         put_device(&teedev->dev);
 906 }
 907 EXPORT_SYMBOL_GPL(tee_device_unregister);
 908
 909 /**
 910  * tee_get_drvdata() - Return driver_data pointer
 911  * @teedev:     Device containing the driver_data pointer
 912  * @returns the driver_data pointer supplied to tee_register().
 913  */
 914 void *tee_get_drvdata(struct tee_device *teedev)
 915 {
 916         return dev_get_drvdata(&teedev->dev);
 917 }
 918 EXPORT_SYMBOL_GPL(tee_get_drvdata);
 919
 920 static int __init tee_init(void)
 921 {
 922         int rc;
 923
 924         tee_class = class_create(THIS_MODULE, "tee");
 925         if (IS_ERR(tee_class)) {
 926                 pr_err("couldn't create class\n");
 927                 return PTR_ERR(tee_class);
 928         }
 929
 930         rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
 931         if (rc) {
 932                 pr_err("failed to allocate char dev region\n");
 933                 class_destroy(tee_class);
 934                 tee_class = NULL;
 935         }
 936
 937         return rc;
 938 }
 939
 940 static void __exit tee_exit(void)
 941 {
 942         class_destroy(tee_class);
 943         tee_class = NULL;
 944         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
 945 }
 946
 947 subsys_initcall(tee_init);
 948 module_exit(tee_exit);
 949
 950 MODULE_AUTHOR("Linaro");
 951 MODULE_DESCRIPTION("TEE Driver");
 952 MODULE_VERSION("1.0");
 953 MODULE_LICENSE("GPL v2");