xref: /optee_os/core/include/kernel/thread.h (revision 511c3c42938673fb9e2fa300af0889b796cb285b)
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 /*
71  * Called by the init CPU. Sets temporary stack mode for all CPUs
72  * (curr_thread = -1 and THREAD_CLF_TMP) and sets the temporary stack limit for
73  * the init CPU.
74  */
75 void thread_init_thread_core_local(void);
76 void thread_init_core_local_stacks(void);
77 
78 #if defined(CFG_CORE_PAUTH)
79 void thread_init_thread_pauth_keys(void);
80 void thread_init_core_local_pauth_keys(void);
81 #else
82 static inline void thread_init_thread_pauth_keys(void) { }
83 static inline void thread_init_core_local_pauth_keys(void) { }
84 #endif
85 
86 /*
87  * Initializes a thread to be used during boot
88  */
89 void thread_init_boot_thread(void);
90 
91 /*
92  * Clears the current thread id
93  * Only supposed to be used during initialization.
94  */
95 void thread_clr_boot_thread(void);
96 
97 /*
98  * Returns current thread id.
99  */
100 short int thread_get_id(void);
101 
102 /*
103  * Returns current thread id, return -1 on failure.
104  */
105 short int thread_get_id_may_fail(void);
106 
107 /* Returns Thread Specific Data (TSD) pointer. */
108 struct thread_specific_data *thread_get_tsd(void);
109 
110 /*
111  * Sets foreign interrupts status for current thread, must only be called
112  * from an active thread context.
113  *
114  * enable == true  -> enable foreign interrupts
115  * enable == false -> disable foreign interrupts
116  */
117 void thread_set_foreign_intr(bool enable);
118 
119 /*
120  * Restores the foreign interrupts status (in CPSR) for current thread, must
121  * only be called from an active thread context.
122  */
123 void thread_restore_foreign_intr(void);
124 
125 /*
126  * thread_get_exceptions() - return current exception mask
127  */
128 uint32_t thread_get_exceptions(void);
129 
130 /*
131  * thread_set_exceptions() - set exception mask
132  * @exceptions: exception mask to set
133  *
134  * Any previous exception mask is replaced by this exception mask, that is,
135  * old bits are cleared and replaced by these.
136  */
137 void thread_set_exceptions(uint32_t exceptions);
138 
139 /*
140  * thread_mask_exceptions() - Masks (disables) specified asynchronous exceptions
141  * @exceptions	exceptions to mask
142  * @returns old exception state
143  */
144 uint32_t thread_mask_exceptions(uint32_t exceptions);
145 
146 /*
147  * thread_unmask_exceptions() - Unmasks asynchronous exceptions
148  * @state	Old asynchronous exception state to restore (returned by
149  *		thread_mask_exceptions())
150  */
151 void thread_unmask_exceptions(uint32_t state);
152 
153 
154 static inline bool __nostackcheck thread_foreign_intr_disabled(void)
155 {
156 	return !!(thread_get_exceptions() & THREAD_EXCP_FOREIGN_INTR);
157 }
158 
159 /*
160  * thread_enter_user_mode() - Enters user mode
161  * @a0:		Passed in r/x0 for user_func
162  * @a1:		Passed in r/x1 for user_func
163  * @a2:		Passed in r/x2 for user_func
164  * @a3:		Passed in r/x3 for user_func
165  * @user_sp:	Assigned sp value in user mode
166  * @user_func:	Function to execute in user mode
167  * @is_32bit:   True if TA should execute in Aarch32, false if Aarch64
168  * @exit_status0: Pointer to opaque exit staus 0
169  * @exit_status1: Pointer to opaque exit staus 1
170  *
171  * This functions enters user mode with the argument described above,
172  * @exit_status0 and @exit_status1 are filled in by thread_unwind_user_mode()
173  * when returning back to the caller of this function through an exception
174  * handler.
175  *
176  * @Returns what's passed in "ret" to thread_unwind_user_mode()
177  */
178 uint32_t thread_enter_user_mode(unsigned long a0, unsigned long a1,
179 		unsigned long a2, unsigned long a3, unsigned long user_sp,
180 		unsigned long entry_func, bool is_32bit,
181 		uint32_t *exit_status0, uint32_t *exit_status1);
182 
183 /*
184  * thread_unwind_user_mode() - Unwinds kernel stack from user entry
185  * @ret:	Value to return from thread_enter_user_mode()
186  * @exit_status0: Exit status 0
187  * @exit_status1: Exit status 1
188  *
189  * This is the function that exception handlers can return into
190  * to resume execution in kernel mode instead of user mode.
191  *
192  * This function is closely coupled with thread_enter_user_mode() since it
193  * need to restore registers saved by thread_enter_user_mode() and when it
194  * returns make it look like thread_enter_user_mode() just returned. It is
195  * expected that the stack pointer is where thread_enter_user_mode() left
196  * it. The stack will be unwound and the function will return to where
197  * thread_enter_user_mode() was called from.  Exit_status0 and exit_status1
198  * are filled in the corresponding pointers supplied to
199  * thread_enter_user_mode().
200  */
201 void thread_unwind_user_mode(uint32_t ret, uint32_t exit_status0,
202 		uint32_t exit_status1);
203 
204 /*
205  * Returns the start address (bottom) of the stack for the current thread,
206  * zero if there is no current thread.
207  */
208 vaddr_t thread_stack_start(void);
209 
210 
211 /* Returns the stack size for the current thread */
212 size_t thread_stack_size(void);
213 
214 /*
215  * Returns the start (top, lowest address) and end (bottom, highest address) of
216  * the current stack (thread, temporary or abort stack).
217  * When CFG_CORE_DEBUG_CHECK_STACKS=y, the @hard parameter tells if the hard or
218  * soft limits are queried. The difference between soft and hard is that for the
219  * latter, the stack start includes some additional space to let any function
220  * overflow the soft limit and still be able to print a stack dump in this case.
221  */
222 bool get_stack_limits(vaddr_t *start, vaddr_t *end, bool hard);
223 
224 static inline bool __nostackcheck get_stack_soft_limits(vaddr_t *start,
225 							vaddr_t *end)
226 {
227 	return get_stack_limits(start, end, false);
228 }
229 
230 static inline bool __nostackcheck get_stack_hard_limits(vaddr_t *start,
231 							vaddr_t *end)
232 {
233 	return get_stack_limits(start, end, true);
234 }
235 
236 bool thread_is_in_normal_mode(void);
237 
238 /*
239  * Returns true if previous exeception also was in abort mode.
240  *
241  * Note: it's only valid to call this function from an abort exception
242  * handler before interrupts has been re-enabled.
243  */
244 bool thread_is_from_abort_mode(void);
245 
246 /**
247  * Allocates data for payload buffers.
248  *
249  * @size:	size in bytes of payload buffer
250  *
251  * @returns	mobj that describes allocated buffer or NULL on error
252  */
253 struct mobj *thread_rpc_alloc_payload(size_t size);
254 
255 /**
256  * Free physical memory previously allocated with thread_rpc_alloc_payload()
257  *
258  * @mobj:	mobj that describes the buffer
259  */
260 void thread_rpc_free_payload(struct mobj *mobj);
261 
262 /**
263  * Allocate data for payload buffers only shared with the non-secure kernel
264  *
265  * @size:	size in bytes of payload buffer
266  *
267  * @returns	mobj that describes allocated buffer or NULL on error
268  */
269 struct mobj *thread_rpc_alloc_kernel_payload(size_t size);
270 
271 /**
272  * Free physical memory previously allocated with
273  * thread_rpc_alloc_kernel_payload()
274  *
275  * @mobj:	mobj that describes the buffer
276  */
277 void thread_rpc_free_kernel_payload(struct mobj *mobj);
278 
279 struct thread_param_memref {
280 	size_t offs;
281 	size_t size;
282 	struct mobj *mobj;
283 };
284 
285 struct thread_param_value {
286 	uint64_t a;
287 	uint64_t b;
288 	uint64_t c;
289 };
290 
291 /*
292  * Note that there's some arithmetics done on the value so it's important
293  * to keep in IN, OUT, INOUT order.
294  */
295 enum thread_param_attr {
296 	THREAD_PARAM_ATTR_NONE = 0,
297 	THREAD_PARAM_ATTR_VALUE_IN,
298 	THREAD_PARAM_ATTR_VALUE_OUT,
299 	THREAD_PARAM_ATTR_VALUE_INOUT,
300 	THREAD_PARAM_ATTR_MEMREF_IN,
301 	THREAD_PARAM_ATTR_MEMREF_OUT,
302 	THREAD_PARAM_ATTR_MEMREF_INOUT,
303 };
304 
305 struct thread_param {
306 	enum thread_param_attr attr;
307 	union {
308 		struct thread_param_memref memref;
309 		struct thread_param_value value;
310 	} u;
311 };
312 
313 #define THREAD_PARAM_MEMREF(_direction, _mobj, _offs, _size) \
314 	(struct thread_param){ \
315 		.attr = THREAD_PARAM_ATTR_MEMREF_ ## _direction, .u.memref = { \
316 		.mobj = (_mobj), .offs = (_offs), .size = (_size) } \
317 	}
318 
319 #define THREAD_PARAM_VALUE(_direction, _a, _b, _c) \
320 	(struct thread_param){ \
321 		.attr = THREAD_PARAM_ATTR_VALUE_ ## _direction, .u.value = { \
322 		.a = (_a), .b = (_b), .c = (_c) } \
323 	}
324 
325 /**
326  * Does an RPC using a preallocated argument buffer
327  * @cmd: RPC cmd
328  * @num_params: number of parameters
329  * @params: RPC parameters
330  * @returns RPC return value
331  */
332 uint32_t thread_rpc_cmd(uint32_t cmd, size_t num_params,
333 		struct thread_param *params);
334 
335 /**
336  * Allocate data for payload buffers.
337  * Buffer is exported to user mode applications.
338  *
339  * @size:	size in bytes of payload buffer
340  *
341  * @returns	mobj that describes allocated buffer or NULL on error
342  */
343 struct mobj *thread_rpc_alloc_global_payload(size_t size);
344 
345 /**
346  * Free physical memory previously allocated with
347  * thread_rpc_alloc_global_payload()
348  *
349  * @mobj:	mobj that describes the buffer
350  */
351 void thread_rpc_free_global_payload(struct mobj *mobj);
352 
353 /*
354  * enum thread_shm_type - type of non-secure shared memory
355  * @THREAD_SHM_TYPE_APPLICATION - user space application shared memory
356  * @THREAD_SHM_TYPE_KERNEL_PRIVATE - kernel private shared memory
357  * @THREAD_SHM_TYPE_GLOBAL - user space and kernel shared memory
358  */
359 enum thread_shm_type {
360 	THREAD_SHM_TYPE_APPLICATION,
361 	THREAD_SHM_TYPE_KERNEL_PRIVATE,
362 	THREAD_SHM_TYPE_GLOBAL,
363 };
364 
365 /*
366  * enum thread_shm_cache_user - user of a cache allocation
367  * @THREAD_SHM_CACHE_USER_SOCKET - socket communication
368  * @THREAD_SHM_CACHE_USER_FS - filesystem access
369  * @THREAD_SHM_CACHE_USER_I2C - I2C communication
370  * @THREAD_SHM_CACHE_USER_RPMB - RPMB communication
371  *
372  * To ensure that each user of the shared memory cache doesn't interfere
373  * with each other a unique ID per user is used.
374  */
375 enum thread_shm_cache_user {
376 	THREAD_SHM_CACHE_USER_SOCKET,
377 	THREAD_SHM_CACHE_USER_FS,
378 	THREAD_SHM_CACHE_USER_I2C,
379 	THREAD_SHM_CACHE_USER_RPMB,
380 };
381 
382 /*
383  * Returns a pointer to the cached RPC memory. Each thread and @user tuple
384  * has a unique cache. The pointer is guaranteed to point to a large enough
385  * area or to be NULL.
386  */
387 void *thread_rpc_shm_cache_alloc(enum thread_shm_cache_user user,
388 				 enum thread_shm_type shm_type,
389 				 size_t size, struct mobj **mobj);
390 
391 #endif /*__ASSEMBLER__*/
392 
393 #endif /*__KERNEL_THREAD_H*/
394