1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/*******************************************************************************
3 *
4 * Module Name: rscalc - Calculate stream and list lengths
5 *
6 ******************************************************************************/
7
8#include <acpi/acpi.h>
9#include "accommon.h"
10#include "acresrc.h"
11#include "acnamesp.h"
12
13#define _COMPONENT ACPI_RESOURCES
14ACPI_MODULE_NAME("rscalc")
15
16/* Local prototypes */
17static u8 acpi_rs_count_set_bits(u16 bit_field);
18
19static acpi_rs_length
20acpi_rs_struct_option_length(struct acpi_resource_source *resource_source);
21
22static u32
23acpi_rs_stream_option_length(u32 resource_length, u32 minimum_total_length);
24
25/*******************************************************************************
26 *
27 * FUNCTION: acpi_rs_count_set_bits
28 *
29 * PARAMETERS: bit_field - Field in which to count bits
30 *
31 * RETURN: Number of bits set within the field
32 *
33 * DESCRIPTION: Count the number of bits set in a resource field. Used for
34 * (Short descriptor) interrupt and DMA lists.
35 *
36 ******************************************************************************/
37
38static u8 acpi_rs_count_set_bits(u16 bit_field)
39{
40 u8 bits_set;
41
42 ACPI_FUNCTION_ENTRY();
43
44 for (bits_set = 0; bit_field; bits_set++) {
45
46 /* Zero the least significant bit that is set */
47
48 bit_field &= (u16) (bit_field - 1);
49 }
50
51 return (bits_set);
52}
53
54/*******************************************************************************
55 *
56 * FUNCTION: acpi_rs_struct_option_length
57 *
58 * PARAMETERS: resource_source - Pointer to optional descriptor field
59 *
60 * RETURN: Status
61 *
62 * DESCRIPTION: Common code to handle optional resource_source_index and
63 * resource_source fields in some Large descriptors. Used during
64 * list-to-stream conversion
65 *
66 ******************************************************************************/
67
68static acpi_rs_length
69acpi_rs_struct_option_length(struct acpi_resource_source *resource_source)
70{
71 ACPI_FUNCTION_ENTRY();
72
73 /*
74 * If the resource_source string is valid, return the size of the string
75 * (string_length includes the NULL terminator) plus the size of the
76 * resource_source_index (1).
77 */
78 if (resource_source->string_ptr) {
79 return ((acpi_rs_length)(resource_source->string_length + 1));
80 }
81
82 return (0);
83}
84
85/*******************************************************************************
86 *
87 * FUNCTION: acpi_rs_stream_option_length
88 *
89 * PARAMETERS: resource_length - Length from the resource header
90 * minimum_total_length - Minimum length of this resource, before
91 * any optional fields. Includes header size
92 *
93 * RETURN: Length of optional string (0 if no string present)
94 *
95 * DESCRIPTION: Common code to handle optional resource_source_index and
96 * resource_source fields in some Large descriptors. Used during
97 * stream-to-list conversion
98 *
99 ******************************************************************************/
100
101static u32
102acpi_rs_stream_option_length(u32 resource_length,
103 u32 minimum_aml_resource_length)
104{
105 u32 string_length = 0;
106
107 ACPI_FUNCTION_ENTRY();
108
109 /*
110 * The resource_source_index and resource_source are optional elements of
111 * some Large-type resource descriptors.
112 */
113
114 /*
115 * If the length of the actual resource descriptor is greater than the
116 * ACPI spec-defined minimum length, it means that a resource_source_index
117 * exists and is followed by a (required) null terminated string. The
118 * string length (including the null terminator) is the resource length
119 * minus the minimum length, minus one byte for the resource_source_index
120 * itself.
121 */
122 if (resource_length > minimum_aml_resource_length) {
123
124 /* Compute the length of the optional string */
125
126 string_length =
127 resource_length - minimum_aml_resource_length - 1;
128 }
129
130 /*
131 * Round the length up to a multiple of the native word in order to
132 * guarantee that the entire resource descriptor is native word aligned
133 */
134 return ((u32) ACPI_ROUND_UP_TO_NATIVE_WORD(string_length));
135}
136
137/*******************************************************************************
138 *
139 * FUNCTION: acpi_rs_get_aml_length
140 *
141 * PARAMETERS: resource - Pointer to the resource linked list
142 * resource_list_size - Size of the resource linked list
143 * size_needed - Where the required size is returned
144 *
145 * RETURN: Status
146 *
147 * DESCRIPTION: Takes a linked list of internal resource descriptors and
148 * calculates the size buffer needed to hold the corresponding
149 * external resource byte stream.
150 *
151 ******************************************************************************/
152
153acpi_status
154acpi_rs_get_aml_length(struct acpi_resource *resource,
155 acpi_size resource_list_size, acpi_size *size_needed)
156{
157 acpi_size aml_size_needed = 0;
158 struct acpi_resource *resource_end;
159 acpi_rs_length total_size;
160
161 ACPI_FUNCTION_TRACE(rs_get_aml_length);
162
163 /* Traverse entire list of internal resource descriptors */
164
165 resource_end =
166 ACPI_ADD_PTR(struct acpi_resource, resource, resource_list_size);
167 while (resource < resource_end) {
168
169 /* Validate the descriptor type */
170
171 if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
172 return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
173 }
174
175 /* Sanity check the length. It must not be zero, or we loop forever */
176
177 if (!resource->length) {
178 return_ACPI_STATUS(AE_AML_BAD_RESOURCE_LENGTH);
179 }
180
181 /* Get the base size of the (external stream) resource descriptor */
182
183 total_size = acpi_gbl_aml_resource_sizes[resource->type];
184
185 /*
186 * Augment the base size for descriptors with optional and/or
187 * variable-length fields
188 */
189 switch (resource->type) {
190 case ACPI_RESOURCE_TYPE_IRQ:
191
192 /* Length can be 3 or 2 */
193
194 if (resource->data.irq.descriptor_length == 2) {
195 total_size--;
196 }
197 break;
198
199 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
200
201 /* Length can be 1 or 0 */
202
203 if (resource->data.irq.descriptor_length == 0) {
204 total_size--;
205 }
206 break;
207
208 case ACPI_RESOURCE_TYPE_VENDOR:
209 /*
210 * Vendor Defined Resource:
211 * For a Vendor Specific resource, if the Length is between 1 and 7
212 * it will be created as a Small Resource data type, otherwise it
213 * is a Large Resource data type.
214 */
215 if (resource->data.vendor.byte_length > 7) {
216
217 /* Base size of a Large resource descriptor */
218
219 total_size =
220 sizeof(struct aml_resource_large_header);
221 }
222
223 /* Add the size of the vendor-specific data */
224
225 total_size = (acpi_rs_length)
226 (total_size + resource->data.vendor.byte_length);
227 break;
228
229 case ACPI_RESOURCE_TYPE_END_TAG:
230 /*
231 * End Tag:
232 * We are done -- return the accumulated total size.
233 */
234 *size_needed = aml_size_needed + total_size;
235
236 /* Normal exit */
237
238 return_ACPI_STATUS(AE_OK);
239
240 case ACPI_RESOURCE_TYPE_ADDRESS16:
241 /*
242 * 16-Bit Address Resource:
243 * Add the size of the optional resource_source info
244 */
245 total_size = (acpi_rs_length)(total_size +
246 acpi_rs_struct_option_length
247 (resource_source: &resource->data.
248 address16.
249 resource_source));
250 break;
251
252 case ACPI_RESOURCE_TYPE_ADDRESS32:
253 /*
254 * 32-Bit Address Resource:
255 * Add the size of the optional resource_source info
256 */
257 total_size = (acpi_rs_length)(total_size +
258 acpi_rs_struct_option_length
259 (resource_source: &resource->data.
260 address32.
261 resource_source));
262 break;
263
264 case ACPI_RESOURCE_TYPE_ADDRESS64:
265 /*
266 * 64-Bit Address Resource:
267 * Add the size of the optional resource_source info
268 */
269 total_size = (acpi_rs_length)(total_size +
270 acpi_rs_struct_option_length
271 (resource_source: &resource->data.
272 address64.
273 resource_source));
274 break;
275
276 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
277 /*
278 * Extended IRQ Resource:
279 * Add the size of each additional optional interrupt beyond the
280 * required 1 (4 bytes for each u32 interrupt number)
281 */
282 total_size = (acpi_rs_length)(total_size +
283 ((resource->data.
284 extended_irq.
285 interrupt_count -
286 1) * 4) +
287 /* Add the size of the optional resource_source info */
288 acpi_rs_struct_option_length
289 (resource_source: &resource->data.
290 extended_irq.
291 resource_source));
292 break;
293
294 case ACPI_RESOURCE_TYPE_GPIO:
295
296 total_size = (acpi_rs_length)(total_size +
297 (resource->data.gpio.
298 pin_table_length * 2) +
299 resource->data.gpio.
300 resource_source.
301 string_length +
302 resource->data.gpio.
303 vendor_length);
304
305 break;
306
307 case ACPI_RESOURCE_TYPE_PIN_FUNCTION:
308
309 total_size = (acpi_rs_length)(total_size +
310 (resource->data.
311 pin_function.
312 pin_table_length * 2) +
313 resource->data.
314 pin_function.
315 resource_source.
316 string_length +
317 resource->data.
318 pin_function.
319 vendor_length);
320
321 break;
322
323 case ACPI_RESOURCE_TYPE_CLOCK_INPUT:
324
325 total_size = (acpi_rs_length)(total_size +
326 resource->data.
327 clock_input.
328 resource_source.
329 string_length);
330
331 break;
332
333 case ACPI_RESOURCE_TYPE_SERIAL_BUS:
334
335 total_size =
336 acpi_gbl_aml_resource_serial_bus_sizes[resource->
337 data.
338 common_serial_bus.
339 type];
340
341 total_size = (acpi_rs_length)(total_size +
342 resource->data.
343 i2c_serial_bus.
344 resource_source.
345 string_length +
346 resource->data.
347 i2c_serial_bus.
348 vendor_length);
349
350 break;
351
352 case ACPI_RESOURCE_TYPE_PIN_CONFIG:
353
354 total_size = (acpi_rs_length)(total_size +
355 (resource->data.
356 pin_config.
357 pin_table_length * 2) +
358 resource->data.pin_config.
359 resource_source.
360 string_length +
361 resource->data.pin_config.
362 vendor_length);
363
364 break;
365
366 case ACPI_RESOURCE_TYPE_PIN_GROUP:
367
368 total_size = (acpi_rs_length)(total_size +
369 (resource->data.pin_group.
370 pin_table_length * 2) +
371 resource->data.pin_group.
372 resource_label.
373 string_length +
374 resource->data.pin_group.
375 vendor_length);
376
377 break;
378
379 case ACPI_RESOURCE_TYPE_PIN_GROUP_FUNCTION:
380
381 total_size = (acpi_rs_length)(total_size +
382 resource->data.
383 pin_group_function.
384 resource_source.
385 string_length +
386 resource->data.
387 pin_group_function.
388 resource_source_label.
389 string_length +
390 resource->data.
391 pin_group_function.
392 vendor_length);
393
394 break;
395
396 case ACPI_RESOURCE_TYPE_PIN_GROUP_CONFIG:
397
398 total_size = (acpi_rs_length)(total_size +
399 resource->data.
400 pin_group_config.
401 resource_source.
402 string_length +
403 resource->data.
404 pin_group_config.
405 resource_source_label.
406 string_length +
407 resource->data.
408 pin_group_config.
409 vendor_length);
410
411 break;
412
413 default:
414
415 break;
416 }
417
418 /* Update the total */
419
420 aml_size_needed += total_size;
421
422 /* Point to the next object */
423
424 resource =
425 ACPI_ADD_PTR(struct acpi_resource, resource,
426 resource->length);
427 }
428
429 /* Did not find an end_tag resource descriptor */
430
431 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
432}
433
434/*******************************************************************************
435 *
436 * FUNCTION: acpi_rs_get_list_length
437 *
438 * PARAMETERS: aml_buffer - Pointer to the resource byte stream
439 * aml_buffer_length - Size of aml_buffer
440 * size_needed - Where the size needed is returned
441 *
442 * RETURN: Status
443 *
444 * DESCRIPTION: Takes an external resource byte stream and calculates the size
445 * buffer needed to hold the corresponding internal resource
446 * descriptor linked list.
447 *
448 ******************************************************************************/
449
450acpi_status
451acpi_rs_get_list_length(u8 *aml_buffer,
452 u32 aml_buffer_length, acpi_size *size_needed)
453{
454 acpi_status status;
455 u8 *end_aml;
456 u8 *buffer;
457 u32 buffer_size;
458 u16 temp16;
459 u16 resource_length;
460 u32 extra_struct_bytes;
461 u8 resource_index;
462 u8 minimum_aml_resource_length;
463 union aml_resource *aml_resource;
464
465 ACPI_FUNCTION_TRACE(rs_get_list_length);
466
467 *size_needed = ACPI_RS_SIZE_MIN; /* Minimum size is one end_tag */
468 end_aml = aml_buffer + aml_buffer_length;
469
470 /* Walk the list of AML resource descriptors */
471
472 while (aml_buffer < end_aml) {
473
474 /* Validate the Resource Type and Resource Length */
475
476 status =
477 acpi_ut_validate_resource(NULL, aml: aml_buffer,
478 return_index: &resource_index);
479 if (ACPI_FAILURE(status)) {
480 /*
481 * Exit on failure. Cannot continue because the descriptor length
482 * may be bogus also.
483 */
484 return_ACPI_STATUS(status);
485 }
486
487 aml_resource = (void *)aml_buffer;
488
489 /* Get the resource length and base (minimum) AML size */
490
491 resource_length = acpi_ut_get_resource_length(aml: aml_buffer);
492 minimum_aml_resource_length =
493 acpi_gbl_resource_aml_sizes[resource_index];
494
495 /*
496 * Augment the size for descriptors with optional
497 * and/or variable length fields
498 */
499 extra_struct_bytes = 0;
500 buffer =
501 aml_buffer + acpi_ut_get_resource_header_length(aml: aml_buffer);
502
503 switch (acpi_ut_get_resource_type(aml: aml_buffer)) {
504 case ACPI_RESOURCE_NAME_IRQ:
505 /*
506 * IRQ Resource:
507 * Get the number of bits set in the 16-bit IRQ mask
508 */
509 ACPI_MOVE_16_TO_16(&temp16, buffer);
510 extra_struct_bytes = acpi_rs_count_set_bits(bit_field: temp16);
511 break;
512
513 case ACPI_RESOURCE_NAME_DMA:
514 /*
515 * DMA Resource:
516 * Get the number of bits set in the 8-bit DMA mask
517 */
518 extra_struct_bytes = acpi_rs_count_set_bits(bit_field: *buffer);
519 break;
520
521 case ACPI_RESOURCE_NAME_VENDOR_SMALL:
522 case ACPI_RESOURCE_NAME_VENDOR_LARGE:
523 /*
524 * Vendor Resource:
525 * Get the number of vendor data bytes
526 */
527 extra_struct_bytes = resource_length;
528
529 /*
530 * There is already one byte included in the minimum
531 * descriptor size. If there are extra struct bytes,
532 * subtract one from the count.
533 */
534 if (extra_struct_bytes) {
535 extra_struct_bytes--;
536 }
537 break;
538
539 case ACPI_RESOURCE_NAME_END_TAG:
540 /*
541 * End Tag: This is the normal exit
542 */
543 return_ACPI_STATUS(AE_OK);
544
545 case ACPI_RESOURCE_NAME_ADDRESS32:
546 case ACPI_RESOURCE_NAME_ADDRESS16:
547 case ACPI_RESOURCE_NAME_ADDRESS64:
548 /*
549 * Address Resource:
550 * Add the size of the optional resource_source
551 */
552 extra_struct_bytes =
553 acpi_rs_stream_option_length(resource_length,
554 minimum_aml_resource_length);
555 break;
556
557 case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
558 /*
559 * Extended IRQ Resource:
560 * Using the interrupt_table_length, add 4 bytes for each additional
561 * interrupt. Note: at least one interrupt is required and is
562 * included in the minimum descriptor size (reason for the -1)
563 */
564 extra_struct_bytes = (buffer[1] - 1) * sizeof(u32);
565
566 /* Add the size of the optional resource_source */
567
568 extra_struct_bytes +=
569 acpi_rs_stream_option_length(resource_length: resource_length -
570 extra_struct_bytes,
571 minimum_aml_resource_length);
572 break;
573
574 case ACPI_RESOURCE_NAME_GPIO:
575
576 /* Vendor data is optional */
577
578 if (aml_resource->gpio.vendor_length) {
579 extra_struct_bytes +=
580 aml_resource->gpio.vendor_offset -
581 aml_resource->gpio.pin_table_offset +
582 aml_resource->gpio.vendor_length;
583 } else {
584 extra_struct_bytes +=
585 aml_resource->large_header.resource_length +
586 sizeof(struct aml_resource_large_header) -
587 aml_resource->gpio.pin_table_offset;
588 }
589 break;
590
591 case ACPI_RESOURCE_NAME_PIN_FUNCTION:
592
593 /* Vendor data is optional */
594
595 if (aml_resource->pin_function.vendor_length) {
596 extra_struct_bytes +=
597 aml_resource->pin_function.vendor_offset -
598 aml_resource->pin_function.
599 pin_table_offset +
600 aml_resource->pin_function.vendor_length;
601 } else {
602 extra_struct_bytes +=
603 aml_resource->large_header.resource_length +
604 sizeof(struct aml_resource_large_header) -
605 aml_resource->pin_function.pin_table_offset;
606 }
607 break;
608
609 case ACPI_RESOURCE_NAME_SERIAL_BUS:{
610
611 /* Avoid undefined behavior: member access within misaligned address */
612
613 struct aml_resource_common_serialbus
614 common_serial_bus;
615 memcpy(&common_serial_bus, aml_resource,
616 sizeof(common_serial_bus));
617
618 minimum_aml_resource_length =
619 acpi_gbl_resource_aml_serial_bus_sizes
620 [common_serial_bus.type];
621 extra_struct_bytes +=
622 common_serial_bus.resource_length -
623 minimum_aml_resource_length;
624 break;
625 }
626
627 case ACPI_RESOURCE_NAME_PIN_CONFIG:
628
629 /* Vendor data is optional */
630
631 if (aml_resource->pin_config.vendor_length) {
632 extra_struct_bytes +=
633 aml_resource->pin_config.vendor_offset -
634 aml_resource->pin_config.pin_table_offset +
635 aml_resource->pin_config.vendor_length;
636 } else {
637 extra_struct_bytes +=
638 aml_resource->large_header.resource_length +
639 sizeof(struct aml_resource_large_header) -
640 aml_resource->pin_config.pin_table_offset;
641 }
642 break;
643
644 case ACPI_RESOURCE_NAME_PIN_GROUP:
645
646 extra_struct_bytes +=
647 aml_resource->pin_group.vendor_offset -
648 aml_resource->pin_group.pin_table_offset +
649 aml_resource->pin_group.vendor_length;
650
651 break;
652
653 case ACPI_RESOURCE_NAME_PIN_GROUP_FUNCTION:
654
655 extra_struct_bytes +=
656 aml_resource->pin_group_function.vendor_offset -
657 aml_resource->pin_group_function.res_source_offset +
658 aml_resource->pin_group_function.vendor_length;
659
660 break;
661
662 case ACPI_RESOURCE_NAME_PIN_GROUP_CONFIG:
663
664 extra_struct_bytes +=
665 aml_resource->pin_group_config.vendor_offset -
666 aml_resource->pin_group_config.res_source_offset +
667 aml_resource->pin_group_config.vendor_length;
668
669 break;
670
671 case ACPI_RESOURCE_NAME_CLOCK_INPUT:
672 extra_struct_bytes =
673 acpi_rs_stream_option_length(resource_length,
674 minimum_aml_resource_length);
675
676 break;
677
678 default:
679
680 break;
681 }
682
683 /*
684 * Update the required buffer size for the internal descriptor structs
685 *
686 * Important: Round the size up for the appropriate alignment. This
687 * is a requirement on IA64.
688 */
689 if (acpi_ut_get_resource_type(aml: aml_buffer) ==
690 ACPI_RESOURCE_NAME_SERIAL_BUS) {
691
692 /* Avoid undefined behavior: member access within misaligned address */
693
694 struct aml_resource_common_serialbus common_serial_bus;
695 memcpy(&common_serial_bus, aml_resource,
696 sizeof(common_serial_bus));
697
698 buffer_size =
699 acpi_gbl_resource_struct_serial_bus_sizes
700 [common_serial_bus.type] + extra_struct_bytes;
701 } else {
702 buffer_size =
703 acpi_gbl_resource_struct_sizes[resource_index] +
704 extra_struct_bytes;
705 }
706
707 buffer_size = (u32)ACPI_ROUND_UP_TO_NATIVE_WORD(buffer_size);
708 *size_needed += buffer_size;
709
710 ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
711 "Type %.2X, AmlLength %.2X InternalLength %.2X%8X\n",
712 acpi_ut_get_resource_type(aml_buffer),
713 acpi_ut_get_descriptor_length(aml_buffer),
714 ACPI_FORMAT_UINT64(*size_needed)));
715
716 /*
717 * Point to the next resource within the AML stream using the length
718 * contained in the resource descriptor header
719 */
720 aml_buffer += acpi_ut_get_descriptor_length(aml: aml_buffer);
721 }
722
723 /* Did not find an end_tag resource descriptor */
724
725 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
726}
727
728/*******************************************************************************
729 *
730 * FUNCTION: acpi_rs_get_pci_routing_table_length
731 *
732 * PARAMETERS: package_object - Pointer to the package object
733 * buffer_size_needed - u32 pointer of the size buffer
734 * needed to properly return the
735 * parsed data
736 *
737 * RETURN: Status
738 *
739 * DESCRIPTION: Given a package representing a PCI routing table, this
740 * calculates the size of the corresponding linked list of
741 * descriptions.
742 *
743 ******************************************************************************/
744
745acpi_status
746acpi_rs_get_pci_routing_table_length(union acpi_operand_object *package_object,
747 acpi_size *buffer_size_needed)
748{
749 u32 number_of_elements;
750 acpi_size temp_size_needed = 0;
751 union acpi_operand_object **top_object_list;
752 u32 index;
753 union acpi_operand_object *package_element;
754 union acpi_operand_object **sub_object_list;
755 u8 name_found;
756 u32 table_index;
757
758 ACPI_FUNCTION_TRACE(rs_get_pci_routing_table_length);
759
760 number_of_elements = package_object->package.count;
761
762 /*
763 * Calculate the size of the return buffer.
764 * The base size is the number of elements * the sizes of the
765 * structures. Additional space for the strings is added below.
766 * The minus one is to subtract the size of the u8 Source[1]
767 * member because it is added below.
768 *
769 * But each PRT_ENTRY structure has a pointer to a string and
770 * the size of that string must be found.
771 */
772 top_object_list = package_object->package.elements;
773
774 for (index = 0; index < number_of_elements; index++) {
775
776 /* Dereference the subpackage */
777
778 package_element = *top_object_list;
779
780 /* We must have a valid Package object */
781
782 if (!package_element ||
783 (package_element->common.type != ACPI_TYPE_PACKAGE)) {
784 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
785 }
786
787 /*
788 * The sub_object_list will now point to an array of the
789 * four IRQ elements: Address, Pin, Source and source_index
790 */
791 sub_object_list = package_element->package.elements;
792
793 /* Scan the irq_table_elements for the Source Name String */
794
795 name_found = FALSE;
796
797 for (table_index = 0;
798 table_index < package_element->package.count
799 && !name_found; table_index++) {
800 if (*sub_object_list && /* Null object allowed */
801 ((ACPI_TYPE_STRING ==
802 (*sub_object_list)->common.type) ||
803 ((ACPI_TYPE_LOCAL_REFERENCE ==
804 (*sub_object_list)->common.type) &&
805 ((*sub_object_list)->reference.class ==
806 ACPI_REFCLASS_NAME)))) {
807 name_found = TRUE;
808 } else {
809 /* Look at the next element */
810
811 sub_object_list++;
812 }
813 }
814
815 temp_size_needed += (sizeof(struct acpi_pci_routing_table) - 4);
816
817 /* Was a String type found? */
818
819 if (name_found) {
820 if ((*sub_object_list)->common.type == ACPI_TYPE_STRING) {
821 /*
822 * The length String.Length field does not include the
823 * terminating NULL, add 1
824 */
825 temp_size_needed += ((acpi_size)
826 (*sub_object_list)->string.
827 length + 1);
828 } else {
829 temp_size_needed += acpi_ns_get_pathname_length(node: (*sub_object_list)->reference.node);
830 }
831 } else {
832 /*
833 * If no name was found, then this is a NULL, which is
834 * translated as a u32 zero.
835 */
836 temp_size_needed += sizeof(u32);
837 }
838
839 /* Round up the size since each element must be aligned */
840
841 temp_size_needed = ACPI_ROUND_UP_TO_64BIT(temp_size_needed);
842
843 /* Point to the next union acpi_operand_object */
844
845 top_object_list++;
846 }
847
848 /*
849 * Add an extra element to the end of the list, essentially a
850 * NULL terminator
851 */
852 *buffer_size_needed =
853 temp_size_needed + sizeof(struct acpi_pci_routing_table);
854 return_ACPI_STATUS(AE_OK);
855}
856

source code of linux/drivers/acpi/acpica/rscalc.c