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