xref: /linux-6.15/include/linux/tee_drv.h (revision 59a135f6)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (c) 2015-2016, Linaro Limited
4  */
5 
6 #ifndef __TEE_DRV_H
7 #define __TEE_DRV_H
8 
9 #include <linux/device.h>
10 #include <linux/idr.h>
11 #include <linux/kref.h>
12 #include <linux/list.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/tee.h>
15 #include <linux/types.h>
16 #include <linux/uuid.h>
17 
18 /*
19  * The file describes the API provided by the generic TEE driver to the
20  * specific TEE driver.
21  */
22 
23 #define TEE_SHM_MAPPED		BIT(0)	/* Memory mapped by the kernel */
24 #define TEE_SHM_DMA_BUF		BIT(1)	/* Memory with dma-buf handle */
25 #define TEE_SHM_EXT_DMA_BUF	BIT(2)	/* Memory with dma-buf handle */
26 #define TEE_SHM_REGISTER	BIT(3)  /* Memory registered in secure world */
27 #define TEE_SHM_USER_MAPPED	BIT(4)  /* Memory mapped in user space */
28 #define TEE_SHM_POOL		BIT(5)  /* Memory allocated from pool */
29 
30 struct device;
31 struct tee_device;
32 struct tee_shm;
33 struct tee_shm_pool;
34 
35 /**
36  * struct tee_context - driver specific context on file pointer data
37  * @teedev:	pointer to this drivers struct tee_device
38  * @list_shm:	List of shared memory object owned by this context
39  * @data:	driver specific context data, managed by the driver
40  * @refcount:	reference counter for this structure
41  * @releasing:  flag that indicates if context is being released right now.
42  *		It is needed to break circular dependency on context during
43  *              shared memory release.
44  * @supp_nowait: flag that indicates that requests in this context should not
45  *              wait for tee-supplicant daemon to be started if not present
46  *              and just return with an error code. It is needed for requests
47  *              that arises from TEE based kernel drivers that should be
48  *              non-blocking in nature.
49  */
50 struct tee_context {
51 	struct tee_device *teedev;
52 	void *data;
53 	struct kref refcount;
54 	bool releasing;
55 	bool supp_nowait;
56 };
57 
58 struct tee_param_memref {
59 	size_t shm_offs;
60 	size_t size;
61 	struct tee_shm *shm;
62 };
63 
64 struct tee_param_value {
65 	u64 a;
66 	u64 b;
67 	u64 c;
68 };
69 
70 struct tee_param {
71 	u64 attr;
72 	union {
73 		struct tee_param_memref memref;
74 		struct tee_param_value value;
75 	} u;
76 };
77 
78 /**
79  * struct tee_driver_ops - driver operations vtable
80  * @get_version:	returns version of driver
81  * @open:		called when the device file is opened
82  * @release:		release this open file
83  * @open_session:	open a new session
84  * @close_session:	close a session
85  * @invoke_func:	invoke a trusted function
86  * @cancel_req:		request cancel of an ongoing invoke or open
87  * @supp_revc:		called for supplicant to get a command
88  * @supp_send:		called for supplicant to send a response
89  * @shm_register:	register shared memory buffer in TEE
90  * @shm_unregister:	unregister shared memory buffer in TEE
91  */
92 struct tee_driver_ops {
93 	void (*get_version)(struct tee_device *teedev,
94 			    struct tee_ioctl_version_data *vers);
95 	int (*open)(struct tee_context *ctx);
96 	void (*release)(struct tee_context *ctx);
97 	int (*open_session)(struct tee_context *ctx,
98 			    struct tee_ioctl_open_session_arg *arg,
99 			    struct tee_param *param);
100 	int (*close_session)(struct tee_context *ctx, u32 session);
101 	int (*invoke_func)(struct tee_context *ctx,
102 			   struct tee_ioctl_invoke_arg *arg,
103 			   struct tee_param *param);
104 	int (*cancel_req)(struct tee_context *ctx, u32 cancel_id, u32 session);
105 	int (*supp_recv)(struct tee_context *ctx, u32 *func, u32 *num_params,
106 			 struct tee_param *param);
107 	int (*supp_send)(struct tee_context *ctx, u32 ret, u32 num_params,
108 			 struct tee_param *param);
109 	int (*shm_register)(struct tee_context *ctx, struct tee_shm *shm,
110 			    struct page **pages, size_t num_pages,
111 			    unsigned long start);
112 	int (*shm_unregister)(struct tee_context *ctx, struct tee_shm *shm);
113 };
114 
115 /**
116  * struct tee_desc - Describes the TEE driver to the subsystem
117  * @name:	name of driver
118  * @ops:	driver operations vtable
119  * @owner:	module providing the driver
120  * @flags:	Extra properties of driver, defined by TEE_DESC_* below
121  */
122 #define TEE_DESC_PRIVILEGED	0x1
123 struct tee_desc {
124 	const char *name;
125 	const struct tee_driver_ops *ops;
126 	struct module *owner;
127 	u32 flags;
128 };
129 
130 /**
131  * tee_device_alloc() - Allocate a new struct tee_device instance
132  * @teedesc:	Descriptor for this driver
133  * @dev:	Parent device for this device
134  * @pool:	Shared memory pool, NULL if not used
135  * @driver_data: Private driver data for this device
136  *
137  * Allocates a new struct tee_device instance. The device is
138  * removed by tee_device_unregister().
139  *
140  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
141  */
142 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
143 				    struct device *dev,
144 				    struct tee_shm_pool *pool,
145 				    void *driver_data);
146 
147 /**
148  * tee_device_register() - Registers a TEE device
149  * @teedev:	Device to register
150  *
151  * tee_device_unregister() need to be called to remove the @teedev if
152  * this function fails.
153  *
154  * @returns < 0 on failure
155  */
156 int tee_device_register(struct tee_device *teedev);
157 
158 /**
159  * tee_device_unregister() - Removes a TEE device
160  * @teedev:	Device to unregister
161  *
162  * This function should be called to remove the @teedev even if
163  * tee_device_register() hasn't been called yet. Does nothing if
164  * @teedev is NULL.
165  */
166 void tee_device_unregister(struct tee_device *teedev);
167 
168 /**
169  * struct tee_shm - shared memory object
170  * @teedev:	device used to allocate the object
171  * @ctx:	context using the object, if NULL the context is gone
172  * @paddr:	physical address of the shared memory
173  * @kaddr:	virtual address of the shared memory
174  * @size:	size of shared memory
175  * @offset:	offset of buffer in user space
176  * @pages:	locked pages from userspace
177  * @num_pages:	number of locked pages
178  * @dmabuf:	dmabuf used to for exporting to user space
179  * @flags:	defined by TEE_SHM_* in tee_drv.h
180  * @id:		unique id of a shared memory object on this device
181  *
182  * This pool is only supposed to be accessed directly from the TEE
183  * subsystem and from drivers that implements their own shm pool manager.
184  */
185 struct tee_shm {
186 	struct tee_device *teedev;
187 	struct tee_context *ctx;
188 	phys_addr_t paddr;
189 	void *kaddr;
190 	size_t size;
191 	unsigned int offset;
192 	struct page **pages;
193 	size_t num_pages;
194 	struct dma_buf *dmabuf;
195 	u32 flags;
196 	int id;
197 };
198 
199 /**
200  * struct tee_shm_pool_mgr - shared memory manager
201  * @ops:		operations
202  * @private_data:	private data for the shared memory manager
203  */
204 struct tee_shm_pool_mgr {
205 	const struct tee_shm_pool_mgr_ops *ops;
206 	void *private_data;
207 };
208 
209 /**
210  * struct tee_shm_pool_mgr_ops - shared memory pool manager operations
211  * @alloc:		called when allocating shared memory
212  * @free:		called when freeing shared memory
213  * @destroy_poolmgr:	called when destroying the pool manager
214  */
215 struct tee_shm_pool_mgr_ops {
216 	int (*alloc)(struct tee_shm_pool_mgr *poolmgr, struct tee_shm *shm,
217 		     size_t size);
218 	void (*free)(struct tee_shm_pool_mgr *poolmgr, struct tee_shm *shm);
219 	void (*destroy_poolmgr)(struct tee_shm_pool_mgr *poolmgr);
220 };
221 
222 /**
223  * tee_shm_pool_alloc() - Create a shared memory pool from shm managers
224  * @priv_mgr:	manager for driver private shared memory allocations
225  * @dmabuf_mgr:	manager for dma-buf shared memory allocations
226  *
227  * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied
228  * in @dmabuf, others will use the range provided by @priv.
229  *
230  * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
231  */
232 struct tee_shm_pool *tee_shm_pool_alloc(struct tee_shm_pool_mgr *priv_mgr,
233 					struct tee_shm_pool_mgr *dmabuf_mgr);
234 
235 /*
236  * tee_shm_pool_mgr_alloc_res_mem() - Create a shm manager for reserved
237  * memory
238  * @vaddr:	Virtual address of start of pool
239  * @paddr:	Physical address of start of pool
240  * @size:	Size in bytes of the pool
241  *
242  * @returns pointer to a 'struct tee_shm_pool_mgr' or an ERR_PTR on failure.
243  */
244 struct tee_shm_pool_mgr *tee_shm_pool_mgr_alloc_res_mem(unsigned long vaddr,
245 							phys_addr_t paddr,
246 							size_t size,
247 							int min_alloc_order);
248 
249 /**
250  * tee_shm_pool_mgr_destroy() - Free a shared memory manager
251  */
252 static inline void tee_shm_pool_mgr_destroy(struct tee_shm_pool_mgr *poolm)
253 {
254 	poolm->ops->destroy_poolmgr(poolm);
255 }
256 
257 /**
258  * struct tee_shm_pool_mem_info - holds information needed to create a shared
259  * memory pool
260  * @vaddr:	Virtual address of start of pool
261  * @paddr:	Physical address of start of pool
262  * @size:	Size in bytes of the pool
263  */
264 struct tee_shm_pool_mem_info {
265 	unsigned long vaddr;
266 	phys_addr_t paddr;
267 	size_t size;
268 };
269 
270 /**
271  * tee_shm_pool_alloc_res_mem() - Create a shared memory pool from reserved
272  * memory range
273  * @priv_info:	 Information for driver private shared memory pool
274  * @dmabuf_info: Information for dma-buf shared memory pool
275  *
276  * Start and end of pools will must be page aligned.
277  *
278  * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied
279  * in @dmabuf, others will use the range provided by @priv.
280  *
281  * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
282  */
283 struct tee_shm_pool *
284 tee_shm_pool_alloc_res_mem(struct tee_shm_pool_mem_info *priv_info,
285 			   struct tee_shm_pool_mem_info *dmabuf_info);
286 
287 /**
288  * tee_shm_pool_free() - Free a shared memory pool
289  * @pool:	The shared memory pool to free
290  *
291  * The must be no remaining shared memory allocated from this pool when
292  * this function is called.
293  */
294 void tee_shm_pool_free(struct tee_shm_pool *pool);
295 
296 /**
297  * tee_get_drvdata() - Return driver_data pointer
298  * @returns the driver_data pointer supplied to tee_register().
299  */
300 void *tee_get_drvdata(struct tee_device *teedev);
301 
302 /**
303  * tee_shm_alloc() - Allocate shared memory
304  * @ctx:	Context that allocates the shared memory
305  * @size:	Requested size of shared memory
306  * @flags:	Flags setting properties for the requested shared memory.
307  *
308  * Memory allocated as global shared memory is automatically freed when the
309  * TEE file pointer is closed. The @flags field uses the bits defined by
310  * TEE_SHM_* above. TEE_SHM_MAPPED must currently always be set. If
311  * TEE_SHM_DMA_BUF global shared memory will be allocated and associated
312  * with a dma-buf handle, else driver private memory.
313  *
314  * @returns a pointer to 'struct tee_shm'
315  */
316 struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags);
317 
318 /**
319  * tee_shm_priv_alloc() - Allocate shared memory privately
320  * @dev:	Device that allocates the shared memory
321  * @size:	Requested size of shared memory
322  *
323  * Allocates shared memory buffer that is not associated with any client
324  * context. Such buffers are owned by TEE driver and used for internal calls.
325  *
326  * @returns a pointer to 'struct tee_shm'
327  */
328 struct tee_shm *tee_shm_priv_alloc(struct tee_device *teedev, size_t size);
329 
330 /**
331  * tee_shm_register() - Register shared memory buffer
332  * @ctx:	Context that registers the shared memory
333  * @addr:	Address is userspace of the shared buffer
334  * @length:	Length of the shared buffer
335  * @flags:	Flags setting properties for the requested shared memory.
336  *
337  * @returns a pointer to 'struct tee_shm'
338  */
339 struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
340 				 size_t length, u32 flags);
341 
342 /**
343  * tee_shm_is_registered() - Check if shared memory object in registered in TEE
344  * @shm:	Shared memory handle
345  * @returns true if object is registered in TEE
346  */
347 static inline bool tee_shm_is_registered(struct tee_shm *shm)
348 {
349 	return shm && (shm->flags & TEE_SHM_REGISTER);
350 }
351 
352 /**
353  * tee_shm_free() - Free shared memory
354  * @shm:	Handle to shared memory to free
355  */
356 void tee_shm_free(struct tee_shm *shm);
357 
358 /**
359  * tee_shm_put() - Decrease reference count on a shared memory handle
360  * @shm:	Shared memory handle
361  */
362 void tee_shm_put(struct tee_shm *shm);
363 
364 /**
365  * tee_shm_va2pa() - Get physical address of a virtual address
366  * @shm:	Shared memory handle
367  * @va:		Virtual address to tranlsate
368  * @pa:		Returned physical address
369  * @returns 0 on success and < 0 on failure
370  */
371 int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa);
372 
373 /**
374  * tee_shm_pa2va() - Get virtual address of a physical address
375  * @shm:	Shared memory handle
376  * @pa:		Physical address to tranlsate
377  * @va:		Returned virtual address
378  * @returns 0 on success and < 0 on failure
379  */
380 int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va);
381 
382 /**
383  * tee_shm_get_va() - Get virtual address of a shared memory plus an offset
384  * @shm:	Shared memory handle
385  * @offs:	Offset from start of this shared memory
386  * @returns virtual address of the shared memory + offs if offs is within
387  *	the bounds of this shared memory, else an ERR_PTR
388  */
389 void *tee_shm_get_va(struct tee_shm *shm, size_t offs);
390 
391 /**
392  * tee_shm_get_pa() - Get physical address of a shared memory plus an offset
393  * @shm:	Shared memory handle
394  * @offs:	Offset from start of this shared memory
395  * @pa:		Physical address to return
396  * @returns 0 if offs is within the bounds of this shared memory, else an
397  *	error code.
398  */
399 int tee_shm_get_pa(struct tee_shm *shm, size_t offs, phys_addr_t *pa);
400 
401 /**
402  * tee_shm_get_size() - Get size of shared memory buffer
403  * @shm:	Shared memory handle
404  * @returns size of shared memory
405  */
406 static inline size_t tee_shm_get_size(struct tee_shm *shm)
407 {
408 	return shm->size;
409 }
410 
411 /**
412  * tee_shm_get_pages() - Get list of pages that hold shared buffer
413  * @shm:	Shared memory handle
414  * @num_pages:	Number of pages will be stored there
415  * @returns pointer to pages array
416  */
417 static inline struct page **tee_shm_get_pages(struct tee_shm *shm,
418 					      size_t *num_pages)
419 {
420 	*num_pages = shm->num_pages;
421 	return shm->pages;
422 }
423 
424 /**
425  * tee_shm_get_page_offset() - Get shared buffer offset from page start
426  * @shm:	Shared memory handle
427  * @returns page offset of shared buffer
428  */
429 static inline size_t tee_shm_get_page_offset(struct tee_shm *shm)
430 {
431 	return shm->offset;
432 }
433 
434 /**
435  * tee_shm_get_id() - Get id of a shared memory object
436  * @shm:	Shared memory handle
437  * @returns id
438  */
439 static inline int tee_shm_get_id(struct tee_shm *shm)
440 {
441 	return shm->id;
442 }
443 
444 /**
445  * tee_shm_get_from_id() - Find shared memory object and increase reference
446  * count
447  * @ctx:	Context owning the shared memory
448  * @id:		Id of shared memory object
449  * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
450  */
451 struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id);
452 
453 /**
454  * tee_client_open_context() - Open a TEE context
455  * @start:	if not NULL, continue search after this context
456  * @match:	function to check TEE device
457  * @data:	data for match function
458  * @vers:	if not NULL, version data of TEE device of the context returned
459  *
460  * This function does an operation similar to open("/dev/teeX") in user space.
461  * A returned context must be released with tee_client_close_context().
462  *
463  * Returns a TEE context of the first TEE device matched by the match()
464  * callback or an ERR_PTR.
465  */
466 struct tee_context *
467 tee_client_open_context(struct tee_context *start,
468 			int (*match)(struct tee_ioctl_version_data *,
469 				     const void *),
470 			const void *data, struct tee_ioctl_version_data *vers);
471 
472 /**
473  * tee_client_close_context() - Close a TEE context
474  * @ctx:	TEE context to close
475  *
476  * Note that all sessions previously opened with this context will be
477  * closed when this function is called.
478  */
479 void tee_client_close_context(struct tee_context *ctx);
480 
481 /**
482  * tee_client_get_version() - Query version of TEE
483  * @ctx:	TEE context to TEE to query
484  * @vers:	Pointer to version data
485  */
486 void tee_client_get_version(struct tee_context *ctx,
487 			    struct tee_ioctl_version_data *vers);
488 
489 /**
490  * tee_client_open_session() - Open a session to a Trusted Application
491  * @ctx:	TEE context
492  * @arg:	Open session arguments, see description of
493  *		struct tee_ioctl_open_session_arg
494  * @param:	Parameters passed to the Trusted Application
495  *
496  * Returns < 0 on error else see @arg->ret for result. If @arg->ret
497  * is TEEC_SUCCESS the session identifier is available in @arg->session.
498  */
499 int tee_client_open_session(struct tee_context *ctx,
500 			    struct tee_ioctl_open_session_arg *arg,
501 			    struct tee_param *param);
502 
503 /**
504  * tee_client_close_session() - Close a session to a Trusted Application
505  * @ctx:	TEE Context
506  * @session:	Session id
507  *
508  * Return < 0 on error else 0, regardless the session will not be
509  * valid after this function has returned.
510  */
511 int tee_client_close_session(struct tee_context *ctx, u32 session);
512 
513 /**
514  * tee_client_invoke_func() - Invoke a function in a Trusted Application
515  * @ctx:	TEE Context
516  * @arg:	Invoke arguments, see description of
517  *		struct tee_ioctl_invoke_arg
518  * @param:	Parameters passed to the Trusted Application
519  *
520  * Returns < 0 on error else see @arg->ret for result.
521  */
522 int tee_client_invoke_func(struct tee_context *ctx,
523 			   struct tee_ioctl_invoke_arg *arg,
524 			   struct tee_param *param);
525 
526 /**
527  * tee_client_cancel_req() - Request cancellation of the previous open-session
528  * or invoke-command operations in a Trusted Application
529  * @ctx:       TEE Context
530  * @arg:       Cancellation arguments, see description of
531  *             struct tee_ioctl_cancel_arg
532  *
533  * Returns < 0 on error else 0 if the cancellation was successfully requested.
534  */
535 int tee_client_cancel_req(struct tee_context *ctx,
536 			  struct tee_ioctl_cancel_arg *arg);
537 
538 static inline bool tee_param_is_memref(struct tee_param *param)
539 {
540 	switch (param->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
541 	case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
542 	case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
543 	case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
544 		return true;
545 	default:
546 		return false;
547 	}
548 }
549 
550 extern struct bus_type tee_bus_type;
551 
552 /**
553  * struct tee_client_device - tee based device
554  * @id:			device identifier
555  * @dev:		device structure
556  */
557 struct tee_client_device {
558 	struct tee_client_device_id id;
559 	struct device dev;
560 };
561 
562 #define to_tee_client_device(d) container_of(d, struct tee_client_device, dev)
563 
564 /**
565  * struct tee_client_driver - tee client driver
566  * @id_table:		device id table supported by this driver
567  * @driver:		driver structure
568  */
569 struct tee_client_driver {
570 	const struct tee_client_device_id *id_table;
571 	struct device_driver driver;
572 };
573 
574 #define to_tee_client_driver(d) \
575 		container_of(d, struct tee_client_driver, driver)
576 
577 #endif /*__TEE_DRV_H*/
578