1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /*******************************************************************************
3  *
4  * Module Name: utstate - state object support procedures
5  *
6  ******************************************************************************/
7 
8 #include <acpi/acpi.h>
9 #include "accommon.h"
10 
11 #define _COMPONENT          ACPI_UTILITIES
12 ACPI_MODULE_NAME("utstate")
13 
14 /*******************************************************************************
15  *
16  * FUNCTION:    acpi_ut_push_generic_state
17  *
18  * PARAMETERS:  list_head           - Head of the state stack
19  *              state               - State object to push
20  *
21  * RETURN:      None
22  *
23  * DESCRIPTION: Push a state object onto a state stack
24  *
25  ******************************************************************************/
26 void
acpi_ut_push_generic_state(union acpi_generic_state ** list_head,union acpi_generic_state * state)27 acpi_ut_push_generic_state(union acpi_generic_state **list_head,
28 			   union acpi_generic_state *state)
29 {
30 	ACPI_FUNCTION_ENTRY();
31 
32 	/* Push the state object onto the front of the list (stack) */
33 
34 	state->common.next = *list_head;
35 	*list_head = state;
36 	return;
37 }
38 
39 /*******************************************************************************
40  *
41  * FUNCTION:    acpi_ut_pop_generic_state
42  *
43  * PARAMETERS:  list_head           - Head of the state stack
44  *
45  * RETURN:      The popped state object
46  *
47  * DESCRIPTION: Pop a state object from a state stack
48  *
49  ******************************************************************************/
50 
acpi_ut_pop_generic_state(union acpi_generic_state ** list_head)51 union acpi_generic_state *acpi_ut_pop_generic_state(union acpi_generic_state
52 						    **list_head)
53 {
54 	union acpi_generic_state *state;
55 
56 	ACPI_FUNCTION_ENTRY();
57 
58 	/* Remove the state object at the head of the list (stack) */
59 
60 	state = *list_head;
61 	if (state) {
62 
63 		/* Update the list head */
64 
65 		*list_head = state->common.next;
66 	}
67 
68 	return (state);
69 }
70 
71 /*******************************************************************************
72  *
73  * FUNCTION:    acpi_ut_create_generic_state
74  *
75  * PARAMETERS:  None
76  *
77  * RETURN:      The new state object. NULL on failure.
78  *
79  * DESCRIPTION: Create a generic state object. Attempt to obtain one from
80  *              the global state cache;  If none available, create a new one.
81  *
82  ******************************************************************************/
83 
acpi_ut_create_generic_state(void)84 union acpi_generic_state *acpi_ut_create_generic_state(void)
85 {
86 	union acpi_generic_state *state;
87 
88 	ACPI_FUNCTION_ENTRY();
89 
90 	state = acpi_os_acquire_object(acpi_gbl_state_cache);
91 	if (state) {
92 
93 		/* Initialize */
94 		state->common.descriptor_type = ACPI_DESC_TYPE_STATE;
95 	}
96 
97 	return (state);
98 }
99 
100 /*******************************************************************************
101  *
102  * FUNCTION:    acpi_ut_create_thread_state
103  *
104  * PARAMETERS:  None
105  *
106  * RETURN:      New Thread State. NULL on failure
107  *
108  * DESCRIPTION: Create a "Thread State" - a flavor of the generic state used
109  *              to track per-thread info during method execution
110  *
111  ******************************************************************************/
112 
acpi_ut_create_thread_state(void)113 struct acpi_thread_state *acpi_ut_create_thread_state(void)
114 {
115 	union acpi_generic_state *state;
116 
117 	ACPI_FUNCTION_ENTRY();
118 
119 	/* Create the generic state object */
120 
121 	state = acpi_ut_create_generic_state();
122 	if (!state) {
123 		return (NULL);
124 	}
125 
126 	/* Init fields specific to the update struct */
127 
128 	state->common.descriptor_type = ACPI_DESC_TYPE_STATE_THREAD;
129 	state->thread.thread_id = acpi_os_get_thread_id();
130 
131 	/* Check for invalid thread ID - zero is very bad, it will break things */
132 
133 	if (!state->thread.thread_id) {
134 		ACPI_ERROR((AE_INFO, "Invalid zero ID from AcpiOsGetThreadId"));
135 		state->thread.thread_id = (acpi_thread_id) 1;
136 	}
137 
138 	return ((struct acpi_thread_state *)state);
139 }
140 
141 /*******************************************************************************
142  *
143  * FUNCTION:    acpi_ut_create_update_state
144  *
145  * PARAMETERS:  object          - Initial Object to be installed in the state
146  *              action          - Update action to be performed
147  *
148  * RETURN:      New state object, null on failure
149  *
150  * DESCRIPTION: Create an "Update State" - a flavor of the generic state used
151  *              to update reference counts and delete complex objects such
152  *              as packages.
153  *
154  ******************************************************************************/
155 
acpi_ut_create_update_state(union acpi_operand_object * object,u16 action)156 union acpi_generic_state *acpi_ut_create_update_state(union acpi_operand_object
157 						      *object, u16 action)
158 {
159 	union acpi_generic_state *state;
160 
161 	ACPI_FUNCTION_ENTRY();
162 
163 	/* Create the generic state object */
164 
165 	state = acpi_ut_create_generic_state();
166 	if (!state) {
167 		return (NULL);
168 	}
169 
170 	/* Init fields specific to the update struct */
171 
172 	state->common.descriptor_type = ACPI_DESC_TYPE_STATE_UPDATE;
173 	state->update.object = object;
174 	state->update.value = action;
175 	return (state);
176 }
177 
178 /*******************************************************************************
179  *
180  * FUNCTION:    acpi_ut_create_pkg_state
181  *
182  * PARAMETERS:  object          - Initial Object to be installed in the state
183  *              action          - Update action to be performed
184  *
185  * RETURN:      New state object, null on failure
186  *
187  * DESCRIPTION: Create a "Package State"
188  *
189  ******************************************************************************/
190 
acpi_ut_create_pkg_state(void * internal_object,void * external_object,u32 index)191 union acpi_generic_state *acpi_ut_create_pkg_state(void *internal_object,
192 						   void *external_object,
193 						   u32 index)
194 {
195 	union acpi_generic_state *state;
196 
197 	ACPI_FUNCTION_ENTRY();
198 
199 	/* Create the generic state object */
200 
201 	state = acpi_ut_create_generic_state();
202 	if (!state) {
203 		return (NULL);
204 	}
205 
206 	/* Init fields specific to the update struct */
207 
208 	state->common.descriptor_type = ACPI_DESC_TYPE_STATE_PACKAGE;
209 	state->pkg.source_object = (union acpi_operand_object *)internal_object;
210 	state->pkg.dest_object = external_object;
211 	state->pkg.index = index;
212 	state->pkg.num_packages = 1;
213 
214 	return (state);
215 }
216 
217 /*******************************************************************************
218  *
219  * FUNCTION:    acpi_ut_create_control_state
220  *
221  * PARAMETERS:  None
222  *
223  * RETURN:      New state object, null on failure
224  *
225  * DESCRIPTION: Create a "Control State" - a flavor of the generic state used
226  *              to support nested IF/WHILE constructs in the AML.
227  *
228  ******************************************************************************/
229 
acpi_ut_create_control_state(void)230 union acpi_generic_state *acpi_ut_create_control_state(void)
231 {
232 	union acpi_generic_state *state;
233 
234 	ACPI_FUNCTION_ENTRY();
235 
236 	/* Create the generic state object */
237 
238 	state = acpi_ut_create_generic_state();
239 	if (!state) {
240 		return (NULL);
241 	}
242 
243 	/* Init fields specific to the control struct */
244 
245 	state->common.descriptor_type = ACPI_DESC_TYPE_STATE_CONTROL;
246 	state->common.state = ACPI_CONTROL_CONDITIONAL_EXECUTING;
247 
248 	return (state);
249 }
250 
251 /*******************************************************************************
252  *
253  * FUNCTION:    acpi_ut_delete_generic_state
254  *
255  * PARAMETERS:  state               - The state object to be deleted
256  *
257  * RETURN:      None
258  *
259  * DESCRIPTION: Release a state object to the state cache. NULL state objects
260  *              are ignored.
261  *
262  ******************************************************************************/
263 
acpi_ut_delete_generic_state(union acpi_generic_state * state)264 void acpi_ut_delete_generic_state(union acpi_generic_state *state)
265 {
266 	ACPI_FUNCTION_ENTRY();
267 
268 	/* Ignore null state */
269 
270 	if (state) {
271 		(void)acpi_os_release_object(acpi_gbl_state_cache, state);
272 	}
273 
274 	return;
275 }
276