Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / tbxface.c
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: tbxface - ACPI table-oriented external interfaces
5  *
6  * Copyright (C) 2000 - 2019, Intel Corp.
7  *
8  *****************************************************************************/
9
10 #define EXPORT_ACPI_INTERFACES
11
12 #include <acpi/acpi.h>
13 #include "accommon.h"
14 #include "actables.h"
15
16 #define _COMPONENT          ACPI_TABLES
17 ACPI_MODULE_NAME("tbxface")
18
19 /*******************************************************************************
20  *
21  * FUNCTION:    acpi_allocate_root_table
22  *
23  * PARAMETERS:  initial_table_count - Size of initial_table_array, in number of
24  *                                    struct acpi_table_desc structures
25  *
26  * RETURN:      Status
27  *
28  * DESCRIPTION: Allocate a root table array. Used by iASL compiler and
29  *              acpi_initialize_tables.
30  *
31  ******************************************************************************/
32 acpi_status acpi_allocate_root_table(u32 initial_table_count)
33 {
34
35         acpi_gbl_root_table_list.max_table_count = initial_table_count;
36         acpi_gbl_root_table_list.flags = ACPI_ROOT_ALLOW_RESIZE;
37
38         return (acpi_tb_resize_root_table_list());
39 }
40
41 /*******************************************************************************
42  *
43  * FUNCTION:    acpi_initialize_tables
44  *
45  * PARAMETERS:  initial_table_array - Pointer to an array of pre-allocated
46  *                                    struct acpi_table_desc structures. If NULL, the
47  *                                    array is dynamically allocated.
48  *              initial_table_count - Size of initial_table_array, in number of
49  *                                    struct acpi_table_desc structures
50  *              allow_resize        - Flag to tell Table Manager if resize of
51  *                                    pre-allocated array is allowed. Ignored
52  *                                    if initial_table_array is NULL.
53  *
54  * RETURN:      Status
55  *
56  * DESCRIPTION: Initialize the table manager, get the RSDP and RSDT/XSDT.
57  *
58  * NOTE:        Allows static allocation of the initial table array in order
59  *              to avoid the use of dynamic memory in confined environments
60  *              such as the kernel boot sequence where it may not be available.
61  *
62  *              If the host OS memory managers are initialized, use NULL for
63  *              initial_table_array, and the table will be dynamically allocated.
64  *
65  ******************************************************************************/
66
67 acpi_status ACPI_INIT_FUNCTION
68 acpi_initialize_tables(struct acpi_table_desc *initial_table_array,
69                        u32 initial_table_count, u8 allow_resize)
70 {
71         acpi_physical_address rsdp_address;
72         acpi_status status;
73
74         ACPI_FUNCTION_TRACE(acpi_initialize_tables);
75
76         /*
77          * Setup the Root Table Array and allocate the table array
78          * if requested
79          */
80         if (!initial_table_array) {
81                 status = acpi_allocate_root_table(initial_table_count);
82                 if (ACPI_FAILURE(status)) {
83                         return_ACPI_STATUS(status);
84                 }
85         } else {
86                 /* Root Table Array has been statically allocated by the host */
87
88                 memset(initial_table_array, 0,
89                        (acpi_size)initial_table_count *
90                        sizeof(struct acpi_table_desc));
91
92                 acpi_gbl_root_table_list.tables = initial_table_array;
93                 acpi_gbl_root_table_list.max_table_count = initial_table_count;
94                 acpi_gbl_root_table_list.flags = ACPI_ROOT_ORIGIN_UNKNOWN;
95                 if (allow_resize) {
96                         acpi_gbl_root_table_list.flags |=
97                             ACPI_ROOT_ALLOW_RESIZE;
98                 }
99         }
100
101         /* Get the address of the RSDP */
102
103         rsdp_address = acpi_os_get_root_pointer();
104         if (!rsdp_address) {
105                 return_ACPI_STATUS(AE_NOT_FOUND);
106         }
107
108         /*
109          * Get the root table (RSDT or XSDT) and extract all entries to the local
110          * Root Table Array. This array contains the information of the RSDT/XSDT
111          * in a common, more usable format.
112          */
113         status = acpi_tb_parse_root_table(rsdp_address);
114         return_ACPI_STATUS(status);
115 }
116
117 ACPI_EXPORT_SYMBOL_INIT(acpi_initialize_tables)
118
119 /*******************************************************************************
120  *
121  * FUNCTION:    acpi_reallocate_root_table
122  *
123  * PARAMETERS:  None
124  *
125  * RETURN:      Status
126  *
127  * DESCRIPTION: Reallocate Root Table List into dynamic memory. Copies the
128  *              root list from the previously provided scratch area. Should
129  *              be called once dynamic memory allocation is available in the
130  *              kernel.
131  *
132  ******************************************************************************/
133 acpi_status ACPI_INIT_FUNCTION acpi_reallocate_root_table(void)
134 {
135         acpi_status status;
136         struct acpi_table_desc *table_desc;
137         u32 i, j;
138
139         ACPI_FUNCTION_TRACE(acpi_reallocate_root_table);
140
141         /*
142          * If there are tables unverified, it is required to reallocate the
143          * root table list to clean up invalid table entries. Otherwise only
144          * reallocate the root table list if the host provided a static buffer
145          * for the table array in the call to acpi_initialize_tables().
146          */
147         if ((acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) &&
148             acpi_gbl_enable_table_validation) {
149                 return_ACPI_STATUS(AE_SUPPORT);
150         }
151
152         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
153
154         /*
155          * Ensure OS early boot logic, which is required by some hosts. If the
156          * table state is reported to be wrong, developers should fix the
157          * issue by invoking acpi_put_table() for the reported table during the
158          * early stage.
159          */
160         for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {
161                 table_desc = &acpi_gbl_root_table_list.tables[i];
162                 if (table_desc->pointer) {
163                         ACPI_ERROR((AE_INFO,
164                                     "Table [%4.4s] is not invalidated during early boot stage",
165                                     table_desc->signature.ascii));
166                 }
167         }
168
169         if (!acpi_gbl_enable_table_validation) {
170                 /*
171                  * Now it's safe to do full table validation. We can do deferred
172                  * table initialization here once the flag is set.
173                  */
174                 acpi_gbl_enable_table_validation = TRUE;
175                 for (i = 0; i < acpi_gbl_root_table_list.current_table_count;
176                      ++i) {
177                         table_desc = &acpi_gbl_root_table_list.tables[i];
178                         if (!(table_desc->flags & ACPI_TABLE_IS_VERIFIED)) {
179                                 status =
180                                     acpi_tb_verify_temp_table(table_desc, NULL,
181                                                               &j);
182                                 if (ACPI_FAILURE(status)) {
183                                         acpi_tb_uninstall_table(table_desc);
184                                 }
185                         }
186                 }
187         }
188
189         acpi_gbl_root_table_list.flags |= ACPI_ROOT_ALLOW_RESIZE;
190         status = acpi_tb_resize_root_table_list();
191         acpi_gbl_root_table_list.flags |= ACPI_ROOT_ORIGIN_ALLOCATED;
192
193         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
194         return_ACPI_STATUS(status);
195 }
196
197 ACPI_EXPORT_SYMBOL_INIT(acpi_reallocate_root_table)
198
199 /*******************************************************************************
200  *
201  * FUNCTION:    acpi_get_table_header
202  *
203  * PARAMETERS:  signature           - ACPI signature of needed table
204  *              instance            - Which instance (for SSDTs)
205  *              out_table_header    - The pointer to the table header to fill
206  *
207  * RETURN:      Status and pointer to mapped table header
208  *
209  * DESCRIPTION: Finds an ACPI table header.
210  *
211  * NOTE:        Caller is responsible in unmapping the header with
212  *              acpi_os_unmap_memory
213  *
214  ******************************************************************************/
215 acpi_status
216 acpi_get_table_header(char *signature,
217                       u32 instance, struct acpi_table_header *out_table_header)
218 {
219         u32 i;
220         u32 j;
221         struct acpi_table_header *header;
222
223         /* Parameter validation */
224
225         if (!signature || !out_table_header) {
226                 return (AE_BAD_PARAMETER);
227         }
228
229         /* Walk the root table list */
230
231         for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
232              i++) {
233                 if (!ACPI_COMPARE_NAMESEG
234                     (&(acpi_gbl_root_table_list.tables[i].signature),
235                      signature)) {
236                         continue;
237                 }
238
239                 if (++j < instance) {
240                         continue;
241                 }
242
243                 if (!acpi_gbl_root_table_list.tables[i].pointer) {
244                         if ((acpi_gbl_root_table_list.tables[i].flags &
245                              ACPI_TABLE_ORIGIN_MASK) ==
246                             ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL) {
247                                 header =
248                                     acpi_os_map_memory(acpi_gbl_root_table_list.
249                                                        tables[i].address,
250                                                        sizeof(struct
251                                                               acpi_table_header));
252                                 if (!header) {
253                                         return (AE_NO_MEMORY);
254                                 }
255
256                                 memcpy(out_table_header, header,
257                                        sizeof(struct acpi_table_header));
258                                 acpi_os_unmap_memory(header,
259                                                      sizeof(struct
260                                                             acpi_table_header));
261                         } else {
262                                 return (AE_NOT_FOUND);
263                         }
264                 } else {
265                         memcpy(out_table_header,
266                                acpi_gbl_root_table_list.tables[i].pointer,
267                                sizeof(struct acpi_table_header));
268                 }
269                 return (AE_OK);
270         }
271
272         return (AE_NOT_FOUND);
273 }
274
275 ACPI_EXPORT_SYMBOL(acpi_get_table_header)
276
277 /*******************************************************************************
278  *
279  * FUNCTION:    acpi_get_table
280  *
281  * PARAMETERS:  signature           - ACPI signature of needed table
282  *              instance            - Which instance (for SSDTs)
283  *              out_table           - Where the pointer to the table is returned
284  *
285  * RETURN:      Status and pointer to the requested table
286  *
287  * DESCRIPTION: Finds and verifies an ACPI table. Table must be in the
288  *              RSDT/XSDT.
289  *              Note that an early stage acpi_get_table() call must be paired
290  *              with an early stage acpi_put_table() call. otherwise the table
291  *              pointer mapped by the early stage mapping implementation may be
292  *              erroneously unmapped by the late stage unmapping implementation
293  *              in an acpi_put_table() invoked during the late stage.
294  *
295  ******************************************************************************/
296 acpi_status
297 acpi_get_table(char *signature,
298                u32 instance, struct acpi_table_header ** out_table)
299 {
300         u32 i;
301         u32 j;
302         acpi_status status = AE_NOT_FOUND;
303         struct acpi_table_desc *table_desc;
304
305         /* Parameter validation */
306
307         if (!signature || !out_table) {
308                 return (AE_BAD_PARAMETER);
309         }
310
311         /*
312          * Note that the following line is required by some OSPMs, they only
313          * check if the returned table is NULL instead of the returned status
314          * to determined if this function is succeeded.
315          */
316         *out_table = NULL;
317
318         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
319
320         /* Walk the root table list */
321
322         for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
323              i++) {
324                 table_desc = &acpi_gbl_root_table_list.tables[i];
325
326                 if (!ACPI_COMPARE_NAMESEG(&table_desc->signature, signature)) {
327                         continue;
328                 }
329
330                 if (++j < instance) {
331                         continue;
332                 }
333
334                 status = acpi_tb_get_table(table_desc, out_table);
335                 break;
336         }
337
338         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
339         return (status);
340 }
341
342 ACPI_EXPORT_SYMBOL(acpi_get_table)
343
344 /*******************************************************************************
345  *
346  * FUNCTION:    acpi_put_table
347  *
348  * PARAMETERS:  table               - The pointer to the table
349  *
350  * RETURN:      None
351  *
352  * DESCRIPTION: Release a table returned by acpi_get_table() and its clones.
353  *              Note that it is not safe if this function was invoked after an
354  *              uninstallation happened to the original table descriptor.
355  *              Currently there is no OSPMs' requirement to handle such
356  *              situations.
357  *
358  ******************************************************************************/
359 void acpi_put_table(struct acpi_table_header *table)
360 {
361         u32 i;
362         struct acpi_table_desc *table_desc;
363
364         ACPI_FUNCTION_TRACE(acpi_put_table);
365
366         if (!table) {
367                 return_VOID;
368         }
369
370         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
371
372         /* Walk the root table list */
373
374         for (i = 0; i < acpi_gbl_root_table_list.current_table_count; i++) {
375                 table_desc = &acpi_gbl_root_table_list.tables[i];
376
377                 if (table_desc->pointer != table) {
378                         continue;
379                 }
380
381                 acpi_tb_put_table(table_desc);
382                 break;
383         }
384
385         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
386         return_VOID;
387 }
388
389 ACPI_EXPORT_SYMBOL(acpi_put_table)
390
391 /*******************************************************************************
392  *
393  * FUNCTION:    acpi_get_table_by_index
394  *
395  * PARAMETERS:  table_index         - Table index
396  *              out_table           - Where the pointer to the table is returned
397  *
398  * RETURN:      Status and pointer to the requested table
399  *
400  * DESCRIPTION: Obtain a table by an index into the global table list. Used
401  *              internally also.
402  *
403  ******************************************************************************/
404 acpi_status
405 acpi_get_table_by_index(u32 table_index, struct acpi_table_header **out_table)
406 {
407         acpi_status status;
408
409         ACPI_FUNCTION_TRACE(acpi_get_table_by_index);
410
411         /* Parameter validation */
412
413         if (!out_table) {
414                 return_ACPI_STATUS(AE_BAD_PARAMETER);
415         }
416
417         /*
418          * Note that the following line is required by some OSPMs, they only
419          * check if the returned table is NULL instead of the returned status
420          * to determined if this function is succeeded.
421          */
422         *out_table = NULL;
423
424         (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
425
426         /* Validate index */
427
428         if (table_index >= acpi_gbl_root_table_list.current_table_count) {
429                 status = AE_BAD_PARAMETER;
430                 goto unlock_and_exit;
431         }
432
433         status =
434             acpi_tb_get_table(&acpi_gbl_root_table_list.tables[table_index],
435                               out_table);
436
437 unlock_and_exit:
438         (void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
439         return_ACPI_STATUS(status);
440 }
441
442 ACPI_EXPORT_SYMBOL(acpi_get_table_by_index)
443
444 /*******************************************************************************
445  *
446  * FUNCTION:    acpi_install_table_handler
447  *
448  * PARAMETERS:  handler         - Table event handler
449  *              context         - Value passed to the handler on each event
450  *
451  * RETURN:      Status
452  *
453  * DESCRIPTION: Install a global table event handler.
454  *
455  ******************************************************************************/
456 acpi_status
457 acpi_install_table_handler(acpi_table_handler handler, void *context)
458 {
459         acpi_status status;
460
461         ACPI_FUNCTION_TRACE(acpi_install_table_handler);
462
463         if (!handler) {
464                 return_ACPI_STATUS(AE_BAD_PARAMETER);
465         }
466
467         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
468         if (ACPI_FAILURE(status)) {
469                 return_ACPI_STATUS(status);
470         }
471
472         /* Don't allow more than one handler */
473
474         if (acpi_gbl_table_handler) {
475                 status = AE_ALREADY_EXISTS;
476                 goto cleanup;
477         }
478
479         /* Install the handler */
480
481         acpi_gbl_table_handler = handler;
482         acpi_gbl_table_handler_context = context;
483
484 cleanup:
485         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
486         return_ACPI_STATUS(status);
487 }
488
489 ACPI_EXPORT_SYMBOL(acpi_install_table_handler)
490
491 /*******************************************************************************
492  *
493  * FUNCTION:    acpi_remove_table_handler
494  *
495  * PARAMETERS:  handler         - Table event handler that was installed
496  *                                previously.
497  *
498  * RETURN:      Status
499  *
500  * DESCRIPTION: Remove a table event handler
501  *
502  ******************************************************************************/
503 acpi_status acpi_remove_table_handler(acpi_table_handler handler)
504 {
505         acpi_status status;
506
507         ACPI_FUNCTION_TRACE(acpi_remove_table_handler);
508
509         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
510         if (ACPI_FAILURE(status)) {
511                 return_ACPI_STATUS(status);
512         }
513
514         /* Make sure that the installed handler is the same */
515
516         if (!handler || handler != acpi_gbl_table_handler) {
517                 status = AE_BAD_PARAMETER;
518                 goto cleanup;
519         }
520
521         /* Remove the handler */
522
523         acpi_gbl_table_handler = NULL;
524
525 cleanup:
526         (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
527         return_ACPI_STATUS(status);
528 }
529
530 ACPI_EXPORT_SYMBOL(acpi_remove_table_handler)