xref: /optee_os/core/include/kernel/thread.h (revision 45fecab081173ef58b1cb14b6ddf6892b0b9d3f6)
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  * Initializes thread contexts. Called in thread_init_boot_thread() if
65  * virtualization is disabled. Virtualization subsystem calls it for
66  * every new guest otherwise.
67  */
68 void thread_init_threads(void);
69 
70 vaddr_t thread_get_abt_stack(void);
71 
72 /*
73  * Called by the init CPU. Sets temporary stack mode for all CPUs
74  * (curr_thread = -1 and THREAD_CLF_TMP) and sets the temporary stack limit for
75  * the init CPU.
76  */
77 void thread_init_thread_core_local(void);
78 void thread_init_core_local_stacks(void);
79 
80 #if defined(CFG_CORE_PAUTH)
81 void thread_init_thread_pauth_keys(void);
82 void thread_init_core_local_pauth_keys(void);
83 #else
84 static inline void thread_init_thread_pauth_keys(void) { }
85 static inline void thread_init_core_local_pauth_keys(void) { }
86 #endif
87 
88 /*
89  * Initializes a thread to be used during boot
90  */
91 void thread_init_boot_thread(void);
92 
93 /*
94  * Clears the current thread id
95  * Only supposed to be used during initialization.
96  */
97 void thread_clr_boot_thread(void);
98 
99 /*
100  * Returns current thread id.
101  */
102 short int thread_get_id(void);
103 
104 /*
105  * Returns current thread id, return -1 on failure.
106  */
107 short int thread_get_id_may_fail(void);
108 
109 /* Returns Thread Specific Data (TSD) pointer. */
110 struct thread_specific_data *thread_get_tsd(void);
111 
112 /*
113  * Sets foreign interrupts status for current thread, must only be called
114  * from an active thread context.
115  *
116  * enable == true  -> enable foreign interrupts
117  * enable == false -> disable foreign interrupts
118  */
119 void thread_set_foreign_intr(bool enable);
120 
121 /*
122  * Restores the foreign interrupts status (in CPSR) for current thread, must
123  * only be called from an active thread context.
124  */
125 void thread_restore_foreign_intr(void);
126 
127 /*
128  * thread_get_exceptions() - return current exception mask
129  */
130 uint32_t thread_get_exceptions(void);
131 
132 /*
133  * thread_set_exceptions() - set exception mask
134  * @exceptions: exception mask to set
135  *
136  * Any previous exception mask is replaced by this exception mask, that is,
137  * old bits are cleared and replaced by these.
138  */
139 void thread_set_exceptions(uint32_t exceptions);
140 
141 /*
142  * thread_mask_exceptions() - Masks (disables) specified asynchronous exceptions
143  * @exceptions	exceptions to mask
144  * @returns old exception state
145  */
146 uint32_t thread_mask_exceptions(uint32_t exceptions);
147 
148 /*
149  * thread_unmask_exceptions() - Unmasks asynchronous exceptions
150  * @state	Old asynchronous exception state to restore (returned by
151  *		thread_mask_exceptions())
152  */
153 void thread_unmask_exceptions(uint32_t state);
154 
155 
156 static inline bool __nostackcheck thread_foreign_intr_disabled(void)
157 {
158 	return !!(thread_get_exceptions() & THREAD_EXCP_FOREIGN_INTR);
159 }
160 
161 /*
162  * thread_enter_user_mode() - Enters user mode
163  * @a0:		Passed in r/x0 for user_func
164  * @a1:		Passed in r/x1 for user_func
165  * @a2:		Passed in r/x2 for user_func
166  * @a3:		Passed in r/x3 for user_func
167  * @user_sp:	Assigned sp value in user mode
168  * @user_func:	Function to execute in user mode
169  * @is_32bit:   True if TA should execute in Aarch32, false if Aarch64
170  * @exit_status0: Pointer to opaque exit staus 0
171  * @exit_status1: Pointer to opaque exit staus 1
172  *
173  * This functions enters user mode with the argument described above,
174  * @exit_status0 and @exit_status1 are filled in by thread_unwind_user_mode()
175  * when returning back to the caller of this function through an exception
176  * handler.
177  *
178  * @Returns what's passed in "ret" to thread_unwind_user_mode()
179  */
180 uint32_t thread_enter_user_mode(unsigned long a0, unsigned long a1,
181 		unsigned long a2, unsigned long a3, unsigned long user_sp,
182 		unsigned long entry_func, bool is_32bit,
183 		uint32_t *exit_status0, uint32_t *exit_status1);
184 
185 /*
186  * thread_unwind_user_mode() - Unwinds kernel stack from user entry
187  * @ret:	Value to return from thread_enter_user_mode()
188  * @exit_status0: Exit status 0
189  * @exit_status1: Exit status 1
190  *
191  * This is the function that exception handlers can return into
192  * to resume execution in kernel mode instead of user mode.
193  *
194  * This function is closely coupled with thread_enter_user_mode() since it
195  * need to restore registers saved by thread_enter_user_mode() and when it
196  * returns make it look like thread_enter_user_mode() just returned. It is
197  * expected that the stack pointer is where thread_enter_user_mode() left
198  * it. The stack will be unwound and the function will return to where
199  * thread_enter_user_mode() was called from.  Exit_status0 and exit_status1
200  * are filled in the corresponding pointers supplied to
201  * thread_enter_user_mode().
202  */
203 void thread_unwind_user_mode(uint32_t ret, uint32_t exit_status0,
204 		uint32_t exit_status1);
205 
206 /*
207  * Returns the start address (bottom) of the stack for the current thread,
208  * zero if there is no current thread.
209  */
210 vaddr_t thread_stack_start(void);
211 
212 
213 /* Returns the stack size for the current thread */
214 size_t thread_stack_size(void);
215 
216 /*
217  * Returns the start (top, lowest address) and end (bottom, highest address) of
218  * the current stack (thread, temporary or abort stack).
219  * When CFG_CORE_DEBUG_CHECK_STACKS=y, the @hard parameter tells if the hard or
220  * soft limits are queried. The difference between soft and hard is that for the
221  * latter, the stack start includes some additional space to let any function
222  * overflow the soft limit and still be able to print a stack dump in this case.
223  */
224 bool get_stack_limits(vaddr_t *start, vaddr_t *end, bool hard);
225 
226 static inline bool __nostackcheck get_stack_soft_limits(vaddr_t *start,
227 							vaddr_t *end)
228 {
229 	return get_stack_limits(start, end, false);
230 }
231 
232 static inline bool __nostackcheck get_stack_hard_limits(vaddr_t *start,
233 							vaddr_t *end)
234 {
235 	return get_stack_limits(start, end, true);
236 }
237 
238 bool thread_is_in_normal_mode(void);
239 
240 /*
241  * Returns true if previous exeception also was in abort mode.
242  *
243  * Note: it's only valid to call this function from an abort exception
244  * handler before interrupts has been re-enabled.
245  */
246 bool thread_is_from_abort_mode(void);
247 
248 /**
249  * Allocates data for payload buffers shared with a non-secure user space
250  * application. Ensure consistency with the enumeration
251  * THREAD_SHM_TYPE_APPLICATION.
252  *
253  * @size:	size in bytes of payload buffer
254  *
255  * @returns	mobj that describes allocated buffer or NULL on error
256  */
257 struct mobj *thread_rpc_alloc_payload(size_t size);
258 
259 /**
260  * Free physical memory previously allocated with thread_rpc_alloc_payload()
261  *
262  * @mobj:	mobj that describes the buffer
263  */
264 void thread_rpc_free_payload(struct mobj *mobj);
265 
266 /**
267  * Allocate data for payload buffers shared with the non-secure kernel.
268  * Ensure consistency with the enumeration THREAD_SHM_TYPE_KERNEL_PRIVATE.
269  *
270  * @size:	size in bytes of payload buffer
271  *
272  * @returns	mobj that describes allocated buffer or NULL on error
273  */
274 struct mobj *thread_rpc_alloc_kernel_payload(size_t size);
275 
276 /**
277  * Free physical memory previously allocated with
278  * thread_rpc_alloc_kernel_payload()
279  *
280  * @mobj:	mobj that describes the buffer
281  */
282 void thread_rpc_free_kernel_payload(struct mobj *mobj);
283 
284 struct thread_param_memref {
285 	size_t offs;
286 	size_t size;
287 	struct mobj *mobj;
288 };
289 
290 struct thread_param_value {
291 	uint64_t a;
292 	uint64_t b;
293 	uint64_t c;
294 };
295 
296 /*
297  * Note that there's some arithmetics done on the value so it's important
298  * to keep in IN, OUT, INOUT order.
299  */
300 enum thread_param_attr {
301 	THREAD_PARAM_ATTR_NONE = 0,
302 	THREAD_PARAM_ATTR_VALUE_IN,
303 	THREAD_PARAM_ATTR_VALUE_OUT,
304 	THREAD_PARAM_ATTR_VALUE_INOUT,
305 	THREAD_PARAM_ATTR_MEMREF_IN,
306 	THREAD_PARAM_ATTR_MEMREF_OUT,
307 	THREAD_PARAM_ATTR_MEMREF_INOUT,
308 };
309 
310 struct thread_param {
311 	enum thread_param_attr attr;
312 	union {
313 		struct thread_param_memref memref;
314 		struct thread_param_value value;
315 	} u;
316 };
317 
318 #define THREAD_PARAM_MEMREF(_direction, _mobj, _offs, _size) \
319 	(struct thread_param){ \
320 		.attr = THREAD_PARAM_ATTR_MEMREF_ ## _direction, .u.memref = { \
321 		.mobj = (_mobj), .offs = (_offs), .size = (_size) } \
322 	}
323 
324 #define THREAD_PARAM_VALUE(_direction, _a, _b, _c) \
325 	(struct thread_param){ \
326 		.attr = THREAD_PARAM_ATTR_VALUE_ ## _direction, .u.value = { \
327 		.a = (_a), .b = (_b), .c = (_c) } \
328 	}
329 
330 /**
331  * Does an RPC using a preallocated argument buffer
332  * @cmd: RPC cmd
333  * @num_params: number of parameters
334  * @params: RPC parameters
335  * @returns RPC return value
336  */
337 uint32_t thread_rpc_cmd(uint32_t cmd, size_t num_params,
338 		struct thread_param *params);
339 
340 /**
341  * Allocate data for payload buffers shared with both user space applications
342  * and the non-secure kernel. Ensure consistency with the enumeration
343  * THREAD_SHM_TYPE_GLOBAL.
344  *
345  * @size:	size in bytes of payload buffer
346  *
347  * @returns	mobj that describes allocated buffer or NULL on error
348  */
349 struct mobj *thread_rpc_alloc_global_payload(size_t size);
350 
351 /**
352  * Free physical memory previously allocated with
353  * thread_rpc_alloc_global_payload()
354  *
355  * @mobj:	mobj that describes the buffer
356  */
357 void thread_rpc_free_global_payload(struct mobj *mobj);
358 
359 /*
360  * enum thread_shm_type - type of non-secure shared memory
361  * @THREAD_SHM_TYPE_APPLICATION - user space application shared memory
362  * @THREAD_SHM_TYPE_KERNEL_PRIVATE - kernel private shared memory
363  * @THREAD_SHM_TYPE_GLOBAL - user space and kernel shared memory
364  */
365 enum thread_shm_type {
366 	THREAD_SHM_TYPE_APPLICATION,
367 	THREAD_SHM_TYPE_KERNEL_PRIVATE,
368 	THREAD_SHM_TYPE_GLOBAL,
369 };
370 
371 /*
372  * enum thread_shm_cache_user - user of a cache allocation
373  * @THREAD_SHM_CACHE_USER_SOCKET - socket communication
374  * @THREAD_SHM_CACHE_USER_FS - filesystem access
375  * @THREAD_SHM_CACHE_USER_I2C - I2C communication
376  * @THREAD_SHM_CACHE_USER_RPMB - RPMB communication
377  *
378  * To ensure that each user of the shared memory cache doesn't interfere
379  * with each other a unique ID per user is used.
380  */
381 enum thread_shm_cache_user {
382 	THREAD_SHM_CACHE_USER_SOCKET,
383 	THREAD_SHM_CACHE_USER_FS,
384 	THREAD_SHM_CACHE_USER_I2C,
385 	THREAD_SHM_CACHE_USER_RPMB,
386 };
387 
388 /*
389  * Returns a pointer to the cached RPC memory. Each thread and @user tuple
390  * has a unique cache. The pointer is guaranteed to point to a large enough
391  * area or to be NULL.
392  */
393 void *thread_rpc_shm_cache_alloc(enum thread_shm_cache_user user,
394 				 enum thread_shm_type shm_type,
395 				 size_t size, struct mobj **mobj);
396 
397 #endif /*__ASSEMBLER__*/
398 
399 #endif /*__KERNEL_THREAD_H*/
400