include/linux/tee_drv.h

   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 #ifndef __TEE_DRV_H
  16 #define __TEE_DRV_H
  17
  18 #include <linux/device.h>
  19 #include <linux/idr.h>
  20 #include <linux/kref.h>
  21 #include <linux/list.h>
  22 #include <linux/mod_devicetable.h>
  23 #include <linux/tee.h>
  24 #include <linux/types.h>
  25 #include <linux/uuid.h>
  26
  27 /*
  28  * The file describes the API provided by the generic TEE driver to the
  29  * specific TEE driver.
  30  */
  31
  32 #define TEE_SHM_MAPPED          BIT(0)  /* Memory mapped by the kernel */
  33 #define TEE_SHM_DMA_BUF         BIT(1)  /* Memory with dma-buf handle */
  34 #define TEE_SHM_EXT_DMA_BUF     BIT(2)  /* Memory with dma-buf handle */
  35 #define TEE_SHM_REGISTER        BIT(3)  /* Memory registered in secure world */
  36 #define TEE_SHM_USER_MAPPED     BIT(4)  /* Memory mapped in user space */
  37 #define TEE_SHM_POOL            BIT(5)  /* Memory allocated from pool */
  38
  39 struct device;
  40 struct tee_device;
  41 struct tee_shm;
  42 struct tee_shm_pool;
  43
  44 /**
  45  * struct tee_context - driver specific context on file pointer data
  46  * @teedev:     pointer to this drivers struct tee_device
  47  * @list_shm:   List of shared memory object owned by this context
  48  * @data:       driver specific context data, managed by the driver
  49  * @refcount:   reference counter for this structure
  50  * @releasing:  flag that indicates if context is being released right now.
  51  *              It is needed to break circular dependency on context during
  52  *              shared memory release.
  53  * @supp_nowait: flag that indicates that requests in this context should not
  54  *              wait for tee-supplicant daemon to be started if not present
  55  *              and just return with an error code. It is needed for requests
  56  *              that arises from TEE based kernel drivers that should be
  57  *              non-blocking in nature.
  58  */
  59 struct tee_context {
  60         struct tee_device *teedev;
  61         struct list_head list_shm;
  62         void *data;
  63         struct kref refcount;
  64         bool releasing;
  65         bool supp_nowait;
  66 };
  67
  68 struct tee_param_memref {
  69         size_t shm_offs;
  70         size_t size;
  71         struct tee_shm *shm;
  72 };
  73
  74 struct tee_param_value {
  75         u64 a;
  76         u64 b;
  77         u64 c;
  78 };
  79
  80 struct tee_param {
  81         u64 attr;
  82         union {
  83                 struct tee_param_memref memref;
  84                 struct tee_param_value value;
  85         } u;
  86 };
  87
  88 /**
  89  * struct tee_driver_ops - driver operations vtable
  90  * @get_version:        returns version of driver
  91  * @open:               called when the device file is opened
  92  * @release:            release this open file
  93  * @open_session:       open a new session
  94  * @close_session:      close a session
  95  * @invoke_func:        invoke a trusted function
  96  * @cancel_req:         request cancel of an ongoing invoke or open
  97  * @supp_revc:          called for supplicant to get a command
  98  * @supp_send:          called for supplicant to send a response
  99  * @shm_register:       register shared memory buffer in TEE
 100  * @shm_unregister:     unregister shared memory buffer in TEE
 101  */
 102 struct tee_driver_ops {
 103         void (*get_version)(struct tee_device *teedev,
 104                             struct tee_ioctl_version_data *vers);
 105         int (*open)(struct tee_context *ctx);
 106         void (*release)(struct tee_context *ctx);
 107         int (*open_session)(struct tee_context *ctx,
 108                             struct tee_ioctl_open_session_arg *arg,
 109                             struct tee_param *param);
 110         int (*close_session)(struct tee_context *ctx, u32 session);
 111         int (*invoke_func)(struct tee_context *ctx,
 112                            struct tee_ioctl_invoke_arg *arg,
 113                            struct tee_param *param);
 114         int (*cancel_req)(struct tee_context *ctx, u32 cancel_id, u32 session);
 115         int (*supp_recv)(struct tee_context *ctx, u32 *func, u32 *num_params,
 116                          struct tee_param *param);
 117         int (*supp_send)(struct tee_context *ctx, u32 ret, u32 num_params,
 118                          struct tee_param *param);
 119         int (*shm_register)(struct tee_context *ctx, struct tee_shm *shm,
 120                             struct page **pages, size_t num_pages,
 121                             unsigned long start);
 122         int (*shm_unregister)(struct tee_context *ctx, struct tee_shm *shm);
 123 };
 124
 125 /**
 126  * struct tee_desc - Describes the TEE driver to the subsystem
 127  * @name:       name of driver
 128  * @ops:        driver operations vtable
 129  * @owner:      module providing the driver
 130  * @flags:      Extra properties of driver, defined by TEE_DESC_* below
 131  */
 132 #define TEE_DESC_PRIVILEGED     0x1
 133 struct tee_desc {
 134         const char *name;
 135         const struct tee_driver_ops *ops;
 136         struct module *owner;
 137         u32 flags;
 138 };
 139
 140 /**
 141  * tee_device_alloc() - Allocate a new struct tee_device instance
 142  * @teedesc:    Descriptor for this driver
 143  * @dev:        Parent device for this device
 144  * @pool:       Shared memory pool, NULL if not used
 145  * @driver_data: Private driver data for this device
 146  *
 147  * Allocates a new struct tee_device instance. The device is
 148  * removed by tee_device_unregister().
 149  *
 150  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
 151  */
 152 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 153                                     struct device *dev,
 154                                     struct tee_shm_pool *pool,
 155                                     void *driver_data);
 156
 157 /**
 158  * tee_device_register() - Registers a TEE device
 159  * @teedev:     Device to register
 160  *
 161  * tee_device_unregister() need to be called to remove the @teedev if
 162  * this function fails.
 163  *
 164  * @returns < 0 on failure
 165  */
 166 int tee_device_register(struct tee_device *teedev);
 167
 168 /**
 169  * tee_device_unregister() - Removes a TEE device
 170  * @teedev:     Device to unregister
 171  *
 172  * This function should be called to remove the @teedev even if
 173  * tee_device_register() hasn't been called yet. Does nothing if
 174  * @teedev is NULL.
 175  */
 176 void tee_device_unregister(struct tee_device *teedev);
 177
 178 /**
 179  * struct tee_shm - shared memory object
 180  * @teedev:     device used to allocate the object
 181  * @ctx:        context using the object, if NULL the context is gone
 182  * @link        link element
 183  * @paddr:      physical address of the shared memory
 184  * @kaddr:      virtual address of the shared memory
 185  * @size:       size of shared memory
 186  * @offset:     offset of buffer in user space
 187  * @pages:      locked pages from userspace
 188  * @num_pages:  number of locked pages
 189  * @dmabuf:     dmabuf used to for exporting to user space
 190  * @flags:      defined by TEE_SHM_* in tee_drv.h
 191  * @id:         unique id of a shared memory object on this device
 192  *
 193  * This pool is only supposed to be accessed directly from the TEE
 194  * subsystem and from drivers that implements their own shm pool manager.
 195  */
 196 struct tee_shm {
 197         struct tee_device *teedev;
 198         struct tee_context *ctx;
 199         struct list_head link;
 200         phys_addr_t paddr;
 201         void *kaddr;
 202         size_t size;
 203         unsigned int offset;
 204         struct page **pages;
 205         size_t num_pages;
 206         struct dma_buf *dmabuf;
 207         u32 flags;
 208         int id;
 209 };
 210
 211 /**
 212  * struct tee_shm_pool_mgr - shared memory manager
 213  * @ops:                operations
 214  * @private_data:       private data for the shared memory manager
 215  */
 216 struct tee_shm_pool_mgr {
 217         const struct tee_shm_pool_mgr_ops *ops;
 218         void *private_data;
 219 };
 220
 221 /**
 222  * struct tee_shm_pool_mgr_ops - shared memory pool manager operations
 223  * @alloc:              called when allocating shared memory
 224  * @free:               called when freeing shared memory
 225  * @destroy_poolmgr:    called when destroying the pool manager
 226  */
 227 struct tee_shm_pool_mgr_ops {
 228         int (*alloc)(struct tee_shm_pool_mgr *poolmgr, struct tee_shm *shm,
 229                      size_t size);
 230         void (*free)(struct tee_shm_pool_mgr *poolmgr, struct tee_shm *shm);
 231         void (*destroy_poolmgr)(struct tee_shm_pool_mgr *poolmgr);
 232 };
 233
 234 /**
 235  * tee_shm_pool_alloc() - Create a shared memory pool from shm managers
 236  * @priv_mgr:   manager for driver private shared memory allocations
 237  * @dmabuf_mgr: manager for dma-buf shared memory allocations
 238  *
 239  * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied
 240  * in @dmabuf, others will use the range provided by @priv.
 241  *
 242  * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
 243  */
 244 struct tee_shm_pool *tee_shm_pool_alloc(struct tee_shm_pool_mgr *priv_mgr,
 245                                         struct tee_shm_pool_mgr *dmabuf_mgr);
 246
 247 /*
 248  * tee_shm_pool_mgr_alloc_res_mem() - Create a shm manager for reserved
 249  * memory
 250  * @vaddr:      Virtual address of start of pool
 251  * @paddr:      Physical address of start of pool
 252  * @size:       Size in bytes of the pool
 253  *
 254  * @returns pointer to a 'struct tee_shm_pool_mgr' or an ERR_PTR on failure.
 255  */
 256 struct tee_shm_pool_mgr *tee_shm_pool_mgr_alloc_res_mem(unsigned long vaddr,
 257                                                         phys_addr_t paddr,
 258                                                         size_t size,
 259                                                         int min_alloc_order);
 260
 261 /**
 262  * tee_shm_pool_mgr_destroy() - Free a shared memory manager
 263  */
 264 static inline void tee_shm_pool_mgr_destroy(struct tee_shm_pool_mgr *poolm)
 265 {
 266         poolm->ops->destroy_poolmgr(poolm);
 267 }
 268
 269 /**
 270  * struct tee_shm_pool_mem_info - holds information needed to create a shared
 271  * memory pool
 272  * @vaddr:      Virtual address of start of pool
 273  * @paddr:      Physical address of start of pool
 274  * @size:       Size in bytes of the pool
 275  */
 276 struct tee_shm_pool_mem_info {
 277         unsigned long vaddr;
 278         phys_addr_t paddr;
 279         size_t size;
 280 };
 281
 282 /**
 283  * tee_shm_pool_alloc_res_mem() - Create a shared memory pool from reserved
 284  * memory range
 285  * @priv_info:   Information for driver private shared memory pool
 286  * @dmabuf_info: Information for dma-buf shared memory pool
 287  *
 288  * Start and end of pools will must be page aligned.
 289  *
 290  * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied
 291  * in @dmabuf, others will use the range provided by @priv.
 292  *
 293  * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
 294  */
 295 struct tee_shm_pool *
 296 tee_shm_pool_alloc_res_mem(struct tee_shm_pool_mem_info *priv_info,
 297                            struct tee_shm_pool_mem_info *dmabuf_info);
 298
 299 /**
 300  * tee_shm_pool_free() - Free a shared memory pool
 301  * @pool:       The shared memory pool to free
 302  *
 303  * The must be no remaining shared memory allocated from this pool when
 304  * this function is called.
 305  */
 306 void tee_shm_pool_free(struct tee_shm_pool *pool);
 307
 308 /**
 309  * tee_get_drvdata() - Return driver_data pointer
 310  * @returns the driver_data pointer supplied to tee_register().
 311  */
 312 void *tee_get_drvdata(struct tee_device *teedev);
 313
 314 /**
 315  * tee_shm_alloc() - Allocate shared memory
 316  * @ctx:        Context that allocates the shared memory
 317  * @size:       Requested size of shared memory
 318  * @flags:      Flags setting properties for the requested shared memory.
 319  *
 320  * Memory allocated as global shared memory is automatically freed when the
 321  * TEE file pointer is closed. The @flags field uses the bits defined by
 322  * TEE_SHM_* above. TEE_SHM_MAPPED must currently always be set. If
 323  * TEE_SHM_DMA_BUF global shared memory will be allocated and associated
 324  * with a dma-buf handle, else driver private memory.
 325  *
 326  * @returns a pointer to 'struct tee_shm'
 327  */
 328 struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags);
 329
 330 /**
 331  * tee_shm_priv_alloc() - Allocate shared memory privately
 332  * @dev:        Device that allocates the shared memory
 333  * @size:       Requested size of shared memory
 334  *
 335  * Allocates shared memory buffer that is not associated with any client
 336  * context. Such buffers are owned by TEE driver and used for internal calls.
 337  *
 338  * @returns a pointer to 'struct tee_shm'
 339  */
 340 struct tee_shm *tee_shm_priv_alloc(struct tee_device *teedev, size_t size);
 341
 342 /**
 343  * tee_shm_register() - Register shared memory buffer
 344  * @ctx:        Context that registers the shared memory
 345  * @addr:       Address is userspace of the shared buffer
 346  * @length:     Length of the shared buffer
 347  * @flags:      Flags setting properties for the requested shared memory.
 348  *
 349  * @returns a pointer to 'struct tee_shm'
 350  */
 351 struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
 352                                  size_t length, u32 flags);
 353
 354 /**
 355  * tee_shm_is_registered() - Check if shared memory object in registered in TEE
 356  * @shm:        Shared memory handle
 357  * @returns true if object is registered in TEE
 358  */
 359 static inline bool tee_shm_is_registered(struct tee_shm *shm)
 360 {
 361         return shm && (shm->flags & TEE_SHM_REGISTER);
 362 }
 363
 364 /**
 365  * tee_shm_free() - Free shared memory
 366  * @shm:        Handle to shared memory to free
 367  */
 368 void tee_shm_free(struct tee_shm *shm);
 369
 370 /**
 371  * tee_shm_put() - Decrease reference count on a shared memory handle
 372  * @shm:        Shared memory handle
 373  */
 374 void tee_shm_put(struct tee_shm *shm);
 375
 376 /**
 377  * tee_shm_va2pa() - Get physical address of a virtual address
 378  * @shm:        Shared memory handle
 379  * @va:         Virtual address to tranlsate
 380  * @pa:         Returned physical address
 381  * @returns 0 on success and < 0 on failure
 382  */
 383 int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa);
 384
 385 /**
 386  * tee_shm_pa2va() - Get virtual address of a physical address
 387  * @shm:        Shared memory handle
 388  * @pa:         Physical address to tranlsate
 389  * @va:         Returned virtual address
 390  * @returns 0 on success and < 0 on failure
 391  */
 392 int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va);
 393
 394 /**
 395  * tee_shm_get_va() - Get virtual address of a shared memory plus an offset
 396  * @shm:        Shared memory handle
 397  * @offs:       Offset from start of this shared memory
 398  * @returns virtual address of the shared memory + offs if offs is within
 399  *      the bounds of this shared memory, else an ERR_PTR
 400  */
 401 void *tee_shm_get_va(struct tee_shm *shm, size_t offs);
 402
 403 /**
 404  * tee_shm_get_pa() - Get physical address of a shared memory plus an offset
 405  * @shm:        Shared memory handle
 406  * @offs:       Offset from start of this shared memory
 407  * @pa:         Physical address to return
 408  * @returns 0 if offs is within the bounds of this shared memory, else an
 409  *      error code.
 410  */
 411 int tee_shm_get_pa(struct tee_shm *shm, size_t offs, phys_addr_t *pa);
 412
 413 /**
 414  * tee_shm_get_size() - Get size of shared memory buffer
 415  * @shm:        Shared memory handle
 416  * @returns size of shared memory
 417  */
 418 static inline size_t tee_shm_get_size(struct tee_shm *shm)
 419 {
 420         return shm->size;
 421 }
 422
 423 /**
 424  * tee_shm_get_pages() - Get list of pages that hold shared buffer
 425  * @shm:        Shared memory handle
 426  * @num_pages:  Number of pages will be stored there
 427  * @returns pointer to pages array
 428  */
 429 static inline struct page **tee_shm_get_pages(struct tee_shm *shm,
 430                                               size_t *num_pages)
 431 {
 432         *num_pages = shm->num_pages;
 433         return shm->pages;
 434 }
 435
 436 /**
 437  * tee_shm_get_page_offset() - Get shared buffer offset from page start
 438  * @shm:        Shared memory handle
 439  * @returns page offset of shared buffer
 440  */
 441 static inline size_t tee_shm_get_page_offset(struct tee_shm *shm)
 442 {
 443         return shm->offset;
 444 }
 445
 446 /**
 447  * tee_shm_get_id() - Get id of a shared memory object
 448  * @shm:        Shared memory handle
 449  * @returns id
 450  */
 451 static inline int tee_shm_get_id(struct tee_shm *shm)
 452 {
 453         return shm->id;
 454 }
 455
 456 /**
 457  * tee_shm_get_from_id() - Find shared memory object and increase reference
 458  * count
 459  * @ctx:        Context owning the shared memory
 460  * @id:         Id of shared memory object
 461  * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
 462  */
 463 struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id);
 464
 465 /**
 466  * tee_client_open_context() - Open a TEE context
 467  * @start:      if not NULL, continue search after this context
 468  * @match:      function to check TEE device
 469  * @data:       data for match function
 470  * @vers:       if not NULL, version data of TEE device of the context returned
 471  *
 472  * This function does an operation similar to open("/dev/teeX") in user space.
 473  * A returned context must be released with tee_client_close_context().
 474  *
 475  * Returns a TEE context of the first TEE device matched by the match()
 476  * callback or an ERR_PTR.
 477  */
 478 struct tee_context *
 479 tee_client_open_context(struct tee_context *start,
 480                         int (*match)(struct tee_ioctl_version_data *,
 481                                      const void *),
 482                         const void *data, struct tee_ioctl_version_data *vers);
 483
 484 /**
 485  * tee_client_close_context() - Close a TEE context
 486  * @ctx:        TEE context to close
 487  *
 488  * Note that all sessions previously opened with this context will be
 489  * closed when this function is called.
 490  */
 491 void tee_client_close_context(struct tee_context *ctx);
 492
 493 /**
 494  * tee_client_get_version() - Query version of TEE
 495  * @ctx:        TEE context to TEE to query
 496  * @vers:       Pointer to version data
 497  */
 498 void tee_client_get_version(struct tee_context *ctx,
 499                             struct tee_ioctl_version_data *vers);
 500
 501 /**
 502  * tee_client_open_session() - Open a session to a Trusted Application
 503  * @ctx:        TEE context
 504  * @arg:        Open session arguments, see description of
 505  *              struct tee_ioctl_open_session_arg
 506  * @param:      Parameters passed to the Trusted Application
 507  *
 508  * Returns < 0 on error else see @arg->ret for result. If @arg->ret
 509  * is TEEC_SUCCESS the session identifier is available in @arg->session.
 510  */
 511 int tee_client_open_session(struct tee_context *ctx,
 512                             struct tee_ioctl_open_session_arg *arg,
 513                             struct tee_param *param);
 514
 515 /**
 516  * tee_client_close_session() - Close a session to a Trusted Application
 517  * @ctx:        TEE Context
 518  * @session:    Session id
 519  *
 520  * Return < 0 on error else 0, regardless the session will not be
 521  * valid after this function has returned.
 522  */
 523 int tee_client_close_session(struct tee_context *ctx, u32 session);
 524
 525 /**
 526  * tee_client_invoke_func() - Invoke a function in a Trusted Application
 527  * @ctx:        TEE Context
 528  * @arg:        Invoke arguments, see description of
 529  *              struct tee_ioctl_invoke_arg
 530  * @param:      Parameters passed to the Trusted Application
 531  *
 532  * Returns < 0 on error else see @arg->ret for result.
 533  */
 534 int tee_client_invoke_func(struct tee_context *ctx,
 535                            struct tee_ioctl_invoke_arg *arg,
 536                            struct tee_param *param);
 537
 538 /**
 539  * tee_client_cancel_req() - Request cancellation of the previous open-session
 540  * or invoke-command operations in a Trusted Application
 541  * @ctx:       TEE Context
 542  * @arg:       Cancellation arguments, see description of
 543  *             struct tee_ioctl_cancel_arg
 544  *
 545  * Returns < 0 on error else 0 if the cancellation was successfully requested.
 546  */
 547 int tee_client_cancel_req(struct tee_context *ctx,
 548                           struct tee_ioctl_cancel_arg *arg);
 549
 550 static inline bool tee_param_is_memref(struct tee_param *param)
 551 {
 552         switch (param->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 553         case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 554         case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 555         case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 556                 return true;
 557         default:
 558                 return false;
 559         }
 560 }
 561
 562 extern struct bus_type tee_bus_type;
 563
 564 /**
 565  * struct tee_client_device - tee based device
 566  * @id:                 device identifier
 567  * @dev:                device structure
 568  */
 569 struct tee_client_device {
 570         struct tee_client_device_id id;
 571         struct device dev;
 572 };
 573
 574 #define to_tee_client_device(d) container_of(d, struct tee_client_device, dev)
 575
 576 /**
 577  * struct tee_client_driver - tee client driver
 578  * @id_table:           device id table supported by this driver
 579  * @driver:             driver structure
 580  */
 581 struct tee_client_driver {
 582         const struct tee_client_device_id *id_table;
 583         struct device_driver driver;
 584 };
 585
 586 #define to_tee_client_driver(d) \
 587                 container_of(d, struct tee_client_driver, driver)
 588
 589 #endif /*__TEE_DRV_H*/