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 - 2023, 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((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(operand[0]->string.pointer,
109				    operand[1]->string.pointer,
110				    operand[2]->string.pointer, &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(start_node,
135						   operand[3]->string.pointer,
136						   ACPI_NS_SEARCH_PARENT,
137						   &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(start_node,
158						   operand[4]->string.pointer,
159						   ACPI_NS_SEARCH_PARENT,
160						   &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);
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(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(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(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(obj_desc, NULL, ACPI_READ,
243						   region_offset, 8, &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(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					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(table, table_header, 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);
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);
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(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