1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: exconfig - Namespace reconfiguration (Load/Unload opcodes)
5 *
6 * Copyright (C) 2000 - 2025, Intel Corp.
7 *
8 *****************************************************************************/
9
10#include <acpi/acpi.h>
11#include "accommon.h"
12#include "acinterp.h"
13#include "acnamesp.h"
14#include "actables.h"
15#include "acdispat.h"
16#include "acevents.h"
17#include "amlcode.h"
18
19#define _COMPONENT ACPI_EXECUTER
20ACPI_MODULE_NAME("exconfig")
21
22/* Local prototypes */
23static acpi_status
24acpi_ex_add_table(u32 table_index, union acpi_operand_object **ddb_handle);
25
26static acpi_status
27acpi_ex_region_read(union acpi_operand_object *obj_desc,
28 u32 length, u8 *buffer);
29
30/*******************************************************************************
31 *
32 * FUNCTION: acpi_ex_add_table
33 *
34 * PARAMETERS: table - Pointer to raw table
35 * parent_node - Where to load the table (scope)
36 * ddb_handle - Where to return the table handle.
37 *
38 * RETURN: Status
39 *
40 * DESCRIPTION: Common function to Install and Load an ACPI table with a
41 * returned table handle.
42 *
43 ******************************************************************************/
44
45static acpi_status
46acpi_ex_add_table(u32 table_index, union acpi_operand_object **ddb_handle)
47{
48 union acpi_operand_object *obj_desc;
49
50 ACPI_FUNCTION_TRACE(ex_add_table);
51
52 /* Create an object to be the table handle */
53
54 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_REFERENCE);
55 if (!obj_desc) {
56 return_ACPI_STATUS(AE_NO_MEMORY);
57 }
58
59 /* Init the table handle */
60
61 obj_desc->common.flags |= AOPOBJ_DATA_VALID;
62 obj_desc->reference.class = ACPI_REFCLASS_TABLE;
63 obj_desc->reference.value = table_index;
64 *ddb_handle = obj_desc;
65 return_ACPI_STATUS(AE_OK);
66}
67
68/*******************************************************************************
69 *
70 * FUNCTION: acpi_ex_load_table_op
71 *
72 * PARAMETERS: walk_state - Current state with operands
73 * return_desc - Where to store the return object
74 *
75 * RETURN: Status
76 *
77 * DESCRIPTION: Load an ACPI table from the RSDT/XSDT
78 *
79 ******************************************************************************/
80
81acpi_status
82acpi_ex_load_table_op(struct acpi_walk_state *walk_state,
83 union acpi_operand_object **return_desc)
84{
85 acpi_status status;
86 union acpi_operand_object **operand = &walk_state->operands[0];
87 struct acpi_namespace_node *parent_node;
88 struct acpi_namespace_node *start_node;
89 struct acpi_namespace_node *parameter_node = NULL;
90 union acpi_operand_object *return_obj;
91 union acpi_operand_object *ddb_handle;
92 u32 table_index;
93
94 ACPI_FUNCTION_TRACE(ex_load_table_op);
95
96 /* Create the return object */
97
98 return_obj = acpi_ut_create_integer_object(value: (u64)0);
99 if (!return_obj) {
100 return_ACPI_STATUS(AE_NO_MEMORY);
101 }
102
103 *return_desc = return_obj;
104
105 /* Find the ACPI table in the RSDT/XSDT */
106
107 acpi_ex_exit_interpreter();
108 status = acpi_tb_find_table(signature: operand[0]->string.pointer,
109 oem_id: operand[1]->string.pointer,
110 oem_table_id: operand[2]->string.pointer, table_index: &table_index);
111 acpi_ex_enter_interpreter();
112 if (ACPI_FAILURE(status)) {
113 if (status != AE_NOT_FOUND) {
114 return_ACPI_STATUS(status);
115 }
116
117 /* Table not found, return an Integer=0 and AE_OK */
118
119 return_ACPI_STATUS(AE_OK);
120 }
121
122 /* Default nodes */
123
124 start_node = walk_state->scope_info->scope.node;
125 parent_node = acpi_gbl_root_node;
126
127 /* root_path (optional parameter) */
128
129 if (operand[3]->string.length > 0) {
130 /*
131 * Find the node referenced by the root_path_string. This is the
132 * location within the namespace where the table will be loaded.
133 */
134 status = acpi_ns_get_node_unlocked(prefix_node: start_node,
135 external_pathname: operand[3]->string.pointer,
136 ACPI_NS_SEARCH_PARENT,
137 out_node: &parent_node);
138 if (ACPI_FAILURE(status)) {
139 return_ACPI_STATUS(status);
140 }
141 }
142
143 /* parameter_path (optional parameter) */
144
145 if (operand[4]->string.length > 0) {
146 if ((operand[4]->string.pointer[0] != AML_ROOT_PREFIX) &&
147 (operand[4]->string.pointer[0] != AML_PARENT_PREFIX)) {
148 /*
149 * Path is not absolute, so it will be relative to the node
150 * referenced by the root_path_string (or the NS root if omitted)
151 */
152 start_node = parent_node;
153 }
154
155 /* Find the node referenced by the parameter_path_string */
156
157 status = acpi_ns_get_node_unlocked(prefix_node: start_node,
158 external_pathname: operand[4]->string.pointer,
159 ACPI_NS_SEARCH_PARENT,
160 out_node: &parameter_node);
161 if (ACPI_FAILURE(status)) {
162 return_ACPI_STATUS(status);
163 }
164 }
165
166 /* Load the table into the namespace */
167
168 ACPI_INFO(("Dynamic OEM Table Load:"));
169 acpi_ex_exit_interpreter();
170 status = acpi_tb_load_table(table_index, parent_node);
171 acpi_ex_enter_interpreter();
172 if (ACPI_FAILURE(status)) {
173 return_ACPI_STATUS(status);
174 }
175
176 status = acpi_ex_add_table(table_index, ddb_handle: &ddb_handle);
177 if (ACPI_FAILURE(status)) {
178 return_ACPI_STATUS(status);
179 }
180
181 /* Complete the initialization/resolution of new objects */
182
183 acpi_ex_exit_interpreter();
184 acpi_ns_initialize_objects();
185 acpi_ex_enter_interpreter();
186
187 /* Parameter Data (optional) */
188
189 if (parameter_node) {
190
191 /* Store the parameter data into the optional parameter object */
192
193 status = acpi_ex_store(val_desc: operand[5],
194 ACPI_CAST_PTR(union acpi_operand_object,
195 parameter_node),
196 walk_state);
197 if (ACPI_FAILURE(status)) {
198 (void)acpi_ex_unload_table(ddb_handle);
199
200 acpi_ut_remove_reference(object: ddb_handle);
201 return_ACPI_STATUS(status);
202 }
203 }
204
205 /* Remove the reference to ddb_handle created by acpi_ex_add_table above */
206
207 acpi_ut_remove_reference(object: ddb_handle);
208
209 /* Return -1 (non-zero) indicates success */
210
211 return_obj->integer.value = 0xFFFFFFFFFFFFFFFF;
212 return_ACPI_STATUS(status);
213}
214
215/*******************************************************************************
216 *
217 * FUNCTION: acpi_ex_region_read
218 *
219 * PARAMETERS: obj_desc - Region descriptor
220 * length - Number of bytes to read
221 * buffer - Pointer to where to put the data
222 *
223 * RETURN: Status
224 *
225 * DESCRIPTION: Read data from an operation region. The read starts from the
226 * beginning of the region.
227 *
228 ******************************************************************************/
229
230static acpi_status
231acpi_ex_region_read(union acpi_operand_object *obj_desc, u32 length, u8 *buffer)
232{
233 acpi_status status;
234 u64 value;
235 u32 region_offset = 0;
236 u32 i;
237
238 /* Bytewise reads */
239
240 for (i = 0; i < length; i++) {
241 status =
242 acpi_ev_address_space_dispatch(region_obj: obj_desc, NULL, ACPI_READ,
243 region_offset, bit_width: 8, value: &value);
244 if (ACPI_FAILURE(status)) {
245 return (status);
246 }
247
248 *buffer = (u8)value;
249 buffer++;
250 region_offset++;
251 }
252
253 return (AE_OK);
254}
255
256/*******************************************************************************
257 *
258 * FUNCTION: acpi_ex_load_op
259 *
260 * PARAMETERS: obj_desc - Region or Buffer/Field where the table will be
261 * obtained
262 * target - Where the status of the load will be stored
263 * walk_state - Current state
264 *
265 * RETURN: Status
266 *
267 * DESCRIPTION: Load an ACPI table from a field or operation region
268 *
269 * NOTE: Region Fields (Field, bank_field, index_fields) are resolved to buffer
270 * objects before this code is reached.
271 *
272 * If source is an operation region, it must refer to system_memory, as
273 * per the ACPI specification.
274 *
275 ******************************************************************************/
276
277acpi_status
278acpi_ex_load_op(union acpi_operand_object *obj_desc,
279 union acpi_operand_object *target,
280 struct acpi_walk_state *walk_state)
281{
282 union acpi_operand_object *ddb_handle;
283 struct acpi_table_header *table_header;
284 struct acpi_table_header *table;
285 u32 table_index;
286 acpi_status status;
287 u32 length;
288
289 ACPI_FUNCTION_TRACE(ex_load_op);
290
291 if (target->common.descriptor_type == ACPI_DESC_TYPE_NAMED) {
292 target =
293 acpi_ns_get_attached_object(ACPI_CAST_PTR
294 (struct acpi_namespace_node,
295 target));
296 }
297 if (target->common.type != ACPI_TYPE_INTEGER) {
298 ACPI_ERROR((AE_INFO, "Type not integer: %X",
299 target->common.type));
300 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
301 }
302
303 target->integer.value = 0;
304
305 /* Source Object can be either an op_region or a Buffer/Field */
306
307 switch (obj_desc->common.type) {
308 case ACPI_TYPE_REGION:
309
310 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
311 "Load table from Region %p\n", obj_desc));
312
313 /* Region must be system_memory (from ACPI spec) */
314
315 if (obj_desc->region.space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) {
316 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
317 }
318
319 /*
320 * If the Region Address and Length have not been previously
321 * evaluated, evaluate them now and save the results.
322 */
323 if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
324 status = acpi_ds_get_region_arguments(rgn_desc: obj_desc);
325 if (ACPI_FAILURE(status)) {
326 return_ACPI_STATUS(status);
327 }
328 }
329
330 /* Get the table header first so we can get the table length */
331
332 table_header = ACPI_ALLOCATE(sizeof(struct acpi_table_header));
333 if (!table_header) {
334 return_ACPI_STATUS(AE_NO_MEMORY);
335 }
336
337 status =
338 acpi_ex_region_read(obj_desc,
339 length: sizeof(struct acpi_table_header),
340 ACPI_CAST_PTR(u8, table_header));
341 length = table_header->length;
342 ACPI_FREE(table_header);
343
344 if (ACPI_FAILURE(status)) {
345 return_ACPI_STATUS(status);
346 }
347
348 /* Must have at least an ACPI table header */
349
350 if (length < sizeof(struct acpi_table_header)) {
351 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
352 }
353
354 /*
355 * The original implementation simply mapped the table, with no copy.
356 * However, the memory region is not guaranteed to remain stable and
357 * we must copy the table to a local buffer. For example, the memory
358 * region is corrupted after suspend on some machines. Dynamically
359 * loaded tables are usually small, so this overhead is minimal.
360 *
361 * The latest implementation (5/2009) does not use a mapping at all.
362 * We use the low-level operation region interface to read the table
363 * instead of the obvious optimization of using a direct mapping.
364 * This maintains a consistent use of operation regions across the
365 * entire subsystem. This is important if additional processing must
366 * be performed in the (possibly user-installed) operation region
367 * handler. For example, acpi_exec and ASLTS depend on this.
368 */
369
370 /* Allocate a buffer for the table */
371
372 table = ACPI_ALLOCATE(length);
373 if (!table) {
374 return_ACPI_STATUS(AE_NO_MEMORY);
375 }
376
377 /* Read the entire table */
378
379 status = acpi_ex_region_read(obj_desc, length,
380 ACPI_CAST_PTR(u8, table));
381 if (ACPI_FAILURE(status)) {
382 ACPI_FREE(table);
383 return_ACPI_STATUS(status);
384 }
385 break;
386
387 case ACPI_TYPE_BUFFER: /* Buffer or resolved region_field */
388
389 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
390 "Load table from Buffer or Field %p\n",
391 obj_desc));
392
393 /* Must have at least an ACPI table header */
394
395 if (obj_desc->buffer.length < sizeof(struct acpi_table_header)) {
396 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
397 }
398
399 /* Get the actual table length from the table header */
400
401 table_header =
402 ACPI_CAST_PTR(struct acpi_table_header,
403 obj_desc->buffer.pointer);
404 length = table_header->length;
405
406 /* Table cannot extend beyond the buffer */
407
408 if (length > obj_desc->buffer.length) {
409 return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
410 }
411 if (length < sizeof(struct acpi_table_header)) {
412 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
413 }
414
415 /*
416 * Copy the table from the buffer because the buffer could be
417 * modified or even deleted in the future
418 */
419 table = ACPI_ALLOCATE(length);
420 if (!table) {
421 return_ACPI_STATUS(AE_NO_MEMORY);
422 }
423
424 memcpy(to: table, from: table_header, len: length);
425 break;
426
427 default:
428
429 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
430 }
431
432 /* Install the new table into the local data structures */
433
434 ACPI_INFO(("Dynamic OEM Table Load:"));
435 acpi_ex_exit_interpreter();
436 status = acpi_tb_install_and_load_table(ACPI_PTR_TO_PHYSADDR(table),
437 ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL,
438 table, TRUE, table_index: &table_index);
439 acpi_ex_enter_interpreter();
440 if (ACPI_FAILURE(status)) {
441
442 /* Delete allocated table buffer */
443
444 ACPI_FREE(table);
445 return_ACPI_STATUS(status);
446 }
447
448 /*
449 * Add the table to the namespace.
450 *
451 * Note: Load the table objects relative to the root of the namespace.
452 * This appears to go against the ACPI specification, but we do it for
453 * compatibility with other ACPI implementations.
454 */
455 status = acpi_ex_add_table(table_index, ddb_handle: &ddb_handle);
456 if (ACPI_FAILURE(status)) {
457 return_ACPI_STATUS(status);
458 }
459
460 /* Complete the initialization/resolution of new objects */
461
462 acpi_ex_exit_interpreter();
463 acpi_ns_initialize_objects();
464 acpi_ex_enter_interpreter();
465
466 /* Remove the reference to ddb_handle created by acpi_ex_add_table above */
467
468 acpi_ut_remove_reference(object: ddb_handle);
469
470 /* Return -1 (non-zero) indicates success */
471
472 target->integer.value = 0xFFFFFFFFFFFFFFFF;
473 return_ACPI_STATUS(status);
474}
475
476/*******************************************************************************
477 *
478 * FUNCTION: acpi_ex_unload_table
479 *
480 * PARAMETERS: ddb_handle - Handle to a previously loaded table
481 *
482 * RETURN: Status
483 *
484 * DESCRIPTION: Unload an ACPI table
485 *
486 ******************************************************************************/
487
488acpi_status acpi_ex_unload_table(union acpi_operand_object *ddb_handle)
489{
490 acpi_status status = AE_OK;
491 union acpi_operand_object *table_desc = ddb_handle;
492 u32 table_index;
493
494 ACPI_FUNCTION_TRACE(ex_unload_table);
495
496 /*
497 * Temporarily emit a warning so that the ASL for the machine can be
498 * hopefully obtained. This is to say that the Unload() operator is
499 * extremely rare if not completely unused.
500 */
501 ACPI_WARNING((AE_INFO, "Received request to unload an ACPI table"));
502
503 /*
504 * May 2018: Unload is no longer supported for the following reasons:
505 * 1) A correct implementation on some hosts may not be possible.
506 * 2) Other ACPI implementations do not correctly/fully support it.
507 * 3) It requires host device driver support which does not exist.
508 * (To properly support namespace unload out from underneath.)
509 * 4) This AML operator has never been seen in the field.
510 */
511 ACPI_EXCEPTION((AE_INFO, AE_NOT_IMPLEMENTED,
512 "AML Unload operator is not supported"));
513
514 /*
515 * Validate the handle
516 * Although the handle is partially validated in acpi_ex_reconfiguration()
517 * when it calls acpi_ex_resolve_operands(), the handle is more completely
518 * validated here.
519 *
520 * Handle must be a valid operand object of type reference. Also, the
521 * ddb_handle must still be marked valid (table has not been previously
522 * unloaded)
523 */
524 if ((!ddb_handle) ||
525 (ACPI_GET_DESCRIPTOR_TYPE(ddb_handle) != ACPI_DESC_TYPE_OPERAND) ||
526 (ddb_handle->common.type != ACPI_TYPE_LOCAL_REFERENCE) ||
527 (!(ddb_handle->common.flags & AOPOBJ_DATA_VALID))) {
528 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
529 }
530
531 /* Get the table index from the ddb_handle */
532
533 table_index = table_desc->reference.value;
534
535 /*
536 * Release the interpreter lock so that the table lock won't have
537 * strict order requirement against it.
538 */
539 acpi_ex_exit_interpreter();
540 status = acpi_tb_unload_table(table_index);
541 acpi_ex_enter_interpreter();
542
543 /*
544 * Invalidate the handle. We do this because the handle may be stored
545 * in a named object and may not be actually deleted until much later.
546 */
547 if (ACPI_SUCCESS(status)) {
548 ddb_handle->common.flags &= ~AOPOBJ_DATA_VALID;
549 }
550 return_ACPI_STATUS(status);
551}
552