xref: /optee_os/core/include/kernel/thread.h (revision 91d4649de98c6beeb8217d40f1fafa50720fe785)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * Copyright (c) 2014, STMicroelectronics International N.V.
4  * Copyright (c) 2016-2017, Linaro Limited
5  * Copyright (c) 2020-2021, Arm Limited
6  */
7 
8 #ifndef __KERNEL_THREAD_H
9 #define __KERNEL_THREAD_H
10 
11 #ifndef __ASSEMBLER__
12 #include <types_ext.h>
13 #include <compiler.h>
14 #include <mm/pgt_cache.h>
15 #endif
16 #include <util.h>
17 #include <kernel/thread_arch.h>
18 
19 #define THREAD_FLAGS_COPY_ARGS_ON_RETURN	BIT(0)
20 #define THREAD_FLAGS_FOREIGN_INTR_ENABLE	BIT(1)
21 #define THREAD_FLAGS_EXIT_ON_FOREIGN_INTR	BIT(2)
22 #define THREAD_FLAGS_FFA_ONLY			BIT(3)
23 
24 #define THREAD_ID_0		0
25 #define THREAD_ID_INVALID	-1
26 
27 #define THREAD_RPC_MAX_NUM_PARAMS	U(4)
28 
29 #ifndef __ASSEMBLER__
30 
31 struct thread_specific_data {
32 	TAILQ_HEAD(, ts_session) sess_stack;
33 	struct ts_ctx *ctx;
34 #ifdef CFG_CORE_FFA
35 	uint32_t rpc_target_info;
36 #endif
37 	uint32_t abort_type;
38 	uint32_t abort_descr;
39 	vaddr_t abort_va;
40 	unsigned int abort_core;
41 	struct thread_abort_regs abort_regs;
42 #ifdef CFG_CORE_DEBUG_CHECK_STACKS
43 	bool stackcheck_recursion;
44 #endif
45 	unsigned int syscall_recursion;
46 #ifdef CFG_FAULT_MITIGATION
47 	struct ftmn_func_arg *ftmn_arg;
48 #endif
49 };
50 
51 void thread_init_canaries(void);
52 void thread_init_primary(void);
53 void thread_init_per_cpu(void);
54 
55 #if defined(CFG_WITH_STACK_CANARIES)
56 void thread_update_canaries(void);
57 #else
58 static inline void thread_update_canaries(void) { }
59 #endif
60 
61 struct thread_core_local *thread_get_core_local(void);
62 
63 /*
64  * thread_init_threads() - Initialize threads
65  * @thread_count: Number of threads to configure
66  *
67  * Initializes thread contexts. Called in thread_init_boot_thread() if
68  * virtualization is disabled. Virtualization subsystem calls it for every
69  * new guest otherwise. @thread_count must be equal to CFG_NUM_THREADS.
70  */
71 void thread_init_threads(size_t thread_count);
72 
73 vaddr_t thread_get_abt_stack(void);
74 
75 /*
76  * thread_init_thread_core_local() - Initialize thread_core_local
77  * @core_count:	Number of cores in the system
78  *
79  * Called by the init CPU. Sets temporary stack mode for all CPUs
80  * (curr_thread = -1 and THREAD_CLF_TMP) and sets the temporary stack limit
81  * for the init CPU. @core_count must be <= CFG_TEE_CORE_NB_CORE, and will
82  * set the number of supported cores to @core_count if configured with
83  * CFG_DYN_CONFIG=y, else @core_count must equal CFG_TEE_CORE_NB_CORE.
84  */
85 void thread_init_thread_core_local(size_t core_count);
86 void thread_init_core_local_stacks(void);
87 
88 #if defined(CFG_CORE_PAUTH)
89 void thread_init_thread_pauth_keys(void);
90 void thread_init_core_local_pauth_keys(void);
91 #else
92 static inline void thread_init_thread_pauth_keys(void) { }
93 static inline void thread_init_core_local_pauth_keys(void) { }
94 #endif
95 
96 /*
97  * Initializes a thread to be used during boot
98  */
99 void thread_init_boot_thread(void);
100 
101 /*
102  * Clears the current thread id
103  * Only supposed to be used during initialization.
104  */
105 void thread_clr_boot_thread(void);
106 
107 /*
108  * Returns current thread id.
109  */
110 short int thread_get_id(void);
111 
112 /*
113  * Returns current thread id, return -1 on failure.
114  */
115 short int thread_get_id_may_fail(void);
116 
117 /* Returns Thread Specific Data (TSD) pointer. */
118 struct thread_specific_data *thread_get_tsd(void);
119 
120 /*
121  * Sets foreign interrupts status for current thread, must only be called
122  * from an active thread context.
123  *
124  * enable == true  -> enable foreign interrupts
125  * enable == false -> disable foreign interrupts
126  */
127 void thread_set_foreign_intr(bool enable);
128 
129 /*
130  * Restores the foreign interrupts status (in CPSR) for current thread, must
131  * only be called from an active thread context.
132  */
133 void thread_restore_foreign_intr(void);
134 
135 /*
136  * thread_get_exceptions() - return current exception mask
137  */
138 uint32_t thread_get_exceptions(void);
139 
140 /*
141  * thread_set_exceptions() - set exception mask
142  * @exceptions: exception mask to set
143  *
144  * Any previous exception mask is replaced by this exception mask, that is,
145  * old bits are cleared and replaced by these.
146  */
147 void thread_set_exceptions(uint32_t exceptions);
148 
149 /*
150  * thread_mask_exceptions() - Masks (disables) specified asynchronous exceptions
151  * @exceptions	exceptions to mask
152  * @returns old exception state
153  */
154 uint32_t thread_mask_exceptions(uint32_t exceptions);
155 
156 /*
157  * thread_unmask_exceptions() - Unmasks asynchronous exceptions
158  * @state	Old asynchronous exception state to restore (returned by
159  *		thread_mask_exceptions())
160  */
161 void thread_unmask_exceptions(uint32_t state);
162 
163 
164 static inline bool __nostackcheck thread_foreign_intr_disabled(void)
165 {
166 	return !!(thread_get_exceptions() & THREAD_EXCP_FOREIGN_INTR);
167 }
168 
169 /*
170  * thread_enter_user_mode() - Enters user mode
171  * @a0:		Passed in r/x0 for user_func
172  * @a1:		Passed in r/x1 for user_func
173  * @a2:		Passed in r/x2 for user_func
174  * @a3:		Passed in r/x3 for user_func
175  * @user_sp:	Assigned sp value in user mode
176  * @user_func:	Function to execute in user mode
177  * @is_32bit:   True if TA should execute in Aarch32, false if Aarch64
178  * @exit_status0: Pointer to opaque exit staus 0
179  * @exit_status1: Pointer to opaque exit staus 1
180  *
181  * This functions enters user mode with the argument described above,
182  * @exit_status0 and @exit_status1 are filled in by thread_unwind_user_mode()
183  * when returning back to the caller of this function through an exception
184  * handler.
185  *
186  * @Returns what's passed in "ret" to thread_unwind_user_mode()
187  */
188 uint32_t thread_enter_user_mode(unsigned long a0, unsigned long a1,
189 		unsigned long a2, unsigned long a3, unsigned long user_sp,
190 		unsigned long entry_func, bool is_32bit,
191 		uint32_t *exit_status0, uint32_t *exit_status1);
192 
193 /*
194  * thread_unwind_user_mode() - Unwinds kernel stack from user entry
195  * @ret:	Value to return from thread_enter_user_mode()
196  * @exit_status0: Exit status 0
197  * @exit_status1: Exit status 1
198  *
199  * This is the function that exception handlers can return into
200  * to resume execution in kernel mode instead of user mode.
201  *
202  * This function is closely coupled with thread_enter_user_mode() since it
203  * need to restore registers saved by thread_enter_user_mode() and when it
204  * returns make it look like thread_enter_user_mode() just returned. It is
205  * expected that the stack pointer is where thread_enter_user_mode() left
206  * it. The stack will be unwound and the function will return to where
207  * thread_enter_user_mode() was called from.  Exit_status0 and exit_status1
208  * are filled in the corresponding pointers supplied to
209  * thread_enter_user_mode().
210  */
211 void thread_unwind_user_mode(uint32_t ret, uint32_t exit_status0,
212 		uint32_t exit_status1);
213 
214 /*
215  * Returns the start address (bottom) of the stack for the current thread,
216  * zero if there is no current thread.
217  */
218 vaddr_t thread_stack_start(void);
219 
220 
221 /* Returns the stack size for the current thread */
222 size_t thread_stack_size(void);
223 
224 /*
225  * Returns the start (top, lowest address) and end (bottom, highest address) of
226  * the current stack (thread, temporary or abort stack).
227  * When CFG_CORE_DEBUG_CHECK_STACKS=y, the @hard parameter tells if the hard or
228  * soft limits are queried. The difference between soft and hard is that for the
229  * latter, the stack start includes some additional space to let any function
230  * overflow the soft limit and still be able to print a stack dump in this case.
231  */
232 bool get_stack_limits(vaddr_t *start, vaddr_t *end, bool hard);
233 
234 static inline bool __nostackcheck get_stack_soft_limits(vaddr_t *start,
235 							vaddr_t *end)
236 {
237 	return get_stack_limits(start, end, false);
238 }
239 
240 static inline bool __nostackcheck get_stack_hard_limits(vaddr_t *start,
241 							vaddr_t *end)
242 {
243 	return get_stack_limits(start, end, true);
244 }
245 
246 bool thread_is_in_normal_mode(void);
247 
248 /*
249  * Returns true if previous exeception also was in abort mode.
250  *
251  * Note: it's only valid to call this function from an abort exception
252  * handler before interrupts has been re-enabled.
253  */
254 bool thread_is_from_abort_mode(void);
255 
256 /**
257  * Allocates data for payload buffers shared with a non-secure user space
258  * application. Ensure consistency with the enumeration
259  * THREAD_SHM_TYPE_APPLICATION.
260  *
261  * @size:	size in bytes of payload buffer
262  *
263  * @returns	mobj that describes allocated buffer or NULL on error
264  */
265 struct mobj *thread_rpc_alloc_payload(size_t size);
266 
267 /**
268  * Free physical memory previously allocated with thread_rpc_alloc_payload()
269  *
270  * @mobj:	mobj that describes the buffer
271  */
272 void thread_rpc_free_payload(struct mobj *mobj);
273 
274 /**
275  * Allocate data for payload buffers shared with the non-secure kernel.
276  * Ensure consistency with the enumeration THREAD_SHM_TYPE_KERNEL_PRIVATE.
277  *
278  * @size:	size in bytes of payload buffer
279  *
280  * @returns	mobj that describes allocated buffer or NULL on error
281  */
282 struct mobj *thread_rpc_alloc_kernel_payload(size_t size);
283 
284 /**
285  * Free physical memory previously allocated with
286  * thread_rpc_alloc_kernel_payload()
287  *
288  * @mobj:	mobj that describes the buffer
289  */
290 void thread_rpc_free_kernel_payload(struct mobj *mobj);
291 
292 struct thread_param_memref {
293 	size_t offs;
294 	size_t size;
295 	struct mobj *mobj;
296 };
297 
298 struct thread_param_value {
299 	uint64_t a;
300 	uint64_t b;
301 	uint64_t c;
302 };
303 
304 /*
305  * Note that there's some arithmetics done on the value so it's important
306  * to keep in IN, OUT, INOUT order.
307  */
308 enum thread_param_attr {
309 	THREAD_PARAM_ATTR_NONE = 0,
310 	THREAD_PARAM_ATTR_VALUE_IN,
311 	THREAD_PARAM_ATTR_VALUE_OUT,
312 	THREAD_PARAM_ATTR_VALUE_INOUT,
313 	THREAD_PARAM_ATTR_MEMREF_IN,
314 	THREAD_PARAM_ATTR_MEMREF_OUT,
315 	THREAD_PARAM_ATTR_MEMREF_INOUT,
316 };
317 
318 struct thread_param {
319 	enum thread_param_attr attr;
320 	union {
321 		struct thread_param_memref memref;
322 		struct thread_param_value value;
323 	} u;
324 };
325 
326 #define THREAD_PARAM_MEMREF(_direction, _mobj, _offs, _size) \
327 	(struct thread_param){ \
328 		.attr = THREAD_PARAM_ATTR_MEMREF_ ## _direction, .u.memref = { \
329 		.mobj = (_mobj), .offs = (_offs), .size = (_size) } \
330 	}
331 
332 #define THREAD_PARAM_VALUE(_direction, _a, _b, _c) \
333 	(struct thread_param){ \
334 		.attr = THREAD_PARAM_ATTR_VALUE_ ## _direction, .u.value = { \
335 		.a = (_a), .b = (_b), .c = (_c) } \
336 	}
337 
338 /**
339  * Does an RPC using a preallocated argument buffer
340  * @cmd: RPC cmd
341  * @num_params: number of parameters
342  * @params: RPC parameters
343  * @returns RPC return value
344  */
345 uint32_t thread_rpc_cmd(uint32_t cmd, size_t num_params,
346 		struct thread_param *params);
347 
348 /**
349  * Allocate data for payload buffers shared with both user space applications
350  * and the non-secure kernel. Ensure consistency with the enumeration
351  * THREAD_SHM_TYPE_GLOBAL.
352  *
353  * @size:	size in bytes of payload buffer
354  *
355  * @returns	mobj that describes allocated buffer or NULL on error
356  */
357 struct mobj *thread_rpc_alloc_global_payload(size_t size);
358 
359 /**
360  * Free physical memory previously allocated with
361  * thread_rpc_alloc_global_payload()
362  *
363  * @mobj:	mobj that describes the buffer
364  */
365 void thread_rpc_free_global_payload(struct mobj *mobj);
366 
367 /*
368  * enum thread_shm_type - type of non-secure shared memory
369  * @THREAD_SHM_TYPE_APPLICATION - user space application shared memory
370  * @THREAD_SHM_TYPE_KERNEL_PRIVATE - kernel private shared memory
371  * @THREAD_SHM_TYPE_GLOBAL - user space and kernel shared memory
372  */
373 enum thread_shm_type {
374 	THREAD_SHM_TYPE_APPLICATION,
375 	THREAD_SHM_TYPE_KERNEL_PRIVATE,
376 	THREAD_SHM_TYPE_GLOBAL,
377 };
378 
379 /*
380  * enum thread_shm_cache_user - user of a cache allocation
381  * @THREAD_SHM_CACHE_USER_SOCKET - socket communication
382  * @THREAD_SHM_CACHE_USER_FS - filesystem access
383  * @THREAD_SHM_CACHE_USER_I2C - I2C communication
384  * @THREAD_SHM_CACHE_USER_RPMB - RPMB communication
385  *
386  * To ensure that each user of the shared memory cache doesn't interfere
387  * with each other a unique ID per user is used.
388  */
389 enum thread_shm_cache_user {
390 	THREAD_SHM_CACHE_USER_SOCKET,
391 	THREAD_SHM_CACHE_USER_FS,
392 	THREAD_SHM_CACHE_USER_I2C,
393 	THREAD_SHM_CACHE_USER_RPMB,
394 };
395 
396 /*
397  * Returns a pointer to the cached RPC memory. Each thread and @user tuple
398  * has a unique cache. The pointer is guaranteed to point to a large enough
399  * area or to be NULL.
400  */
401 void *thread_rpc_shm_cache_alloc(enum thread_shm_cache_user user,
402 				 enum thread_shm_type shm_type,
403 				 size_t size, struct mobj **mobj);
404 
405 #endif /*__ASSEMBLER__*/
406 
407 #endif /*__KERNEL_THREAD_H*/
408