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1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.02/*******************************************************************************3 *4 * Module Name: rscalc - Calculate stream and list lengths5 *6 ******************************************************************************/7 8#include <acpi/acpi.h>9#include "accommon.h"10#include "acresrc.h"11#include "acnamesp.h"12 13#define _COMPONENT          ACPI_RESOURCES14ACPI_MODULE_NAME("rscalc")15 16/* Local prototypes */17static u8 acpi_rs_count_set_bits(u16 bit_field);18 19static acpi_rs_length20acpi_rs_struct_option_length(struct acpi_resource_source *resource_source);21 22static u3223acpi_rs_stream_option_length(u32 resource_length, u32 minimum_total_length);24 25/*******************************************************************************26 *27 * FUNCTION:    acpi_rs_count_set_bits28 *29 * PARAMETERS:  bit_field       - Field in which to count bits30 *31 * RETURN:      Number of bits set within the field32 *33 * DESCRIPTION: Count the number of bits set in a resource field. Used for34 *              (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_length57 *58 * PARAMETERS:  resource_source     - Pointer to optional descriptor field59 *60 * RETURN:      Status61 *62 * DESCRIPTION: Common code to handle optional resource_source_index and63 *              resource_source fields in some Large descriptors. Used during64 *              list-to-stream conversion65 *66 ******************************************************************************/67 68static acpi_rs_length69acpi_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 string75	 * (string_length includes the NULL terminator) plus the size of the76	 * 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_length88 *89 * PARAMETERS:  resource_length     - Length from the resource header90 *              minimum_total_length - Minimum length of this resource, before91 *                                    any optional fields. Includes header size92 *93 * RETURN:      Length of optional string (0 if no string present)94 *95 * DESCRIPTION: Common code to handle optional resource_source_index and96 *              resource_source fields in some Large descriptors. Used during97 *              stream-to-list conversion98 *99 ******************************************************************************/100 101static u32102acpi_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 of111	 * some Large-type resource descriptors.112	 */113 114	/*115	 * If the length of the actual resource descriptor is greater than the116	 * ACPI spec-defined minimum length, it means that a resource_source_index117	 * exists and is followed by a (required) null terminated string. The118	 * string length (including the null terminator) is the resource length119	 * minus the minimum length, minus one byte for the resource_source_index120	 * 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 to132	 * guarantee that the entire resource descriptor is native word aligned133	 */134	return ((u32) ACPI_ROUND_UP_TO_NATIVE_WORD(string_length));135}136 137/*******************************************************************************138 *139 * FUNCTION:    acpi_rs_get_aml_length140 *141 * PARAMETERS:  resource            - Pointer to the resource linked list142 *              resource_list_size  - Size of the resource linked list143 *              size_needed         - Where the required size is returned144 *145 * RETURN:      Status146 *147 * DESCRIPTION: Takes a linked list of internal resource descriptors and148 *              calculates the size buffer needed to hold the corresponding149 *              external resource byte stream.150 *151 ******************************************************************************/152 153acpi_status154acpi_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/or187		 * variable-length fields188		 */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 7212			 * it will be created as a Small Resource data type, otherwise it213			 * 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 info244			 */245			total_size = (acpi_rs_length)(total_size +246						      acpi_rs_struct_option_length247						      (&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 info256			 */257			total_size = (acpi_rs_length)(total_size +258						      acpi_rs_struct_option_length259						      (&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 info268			 */269			total_size = (acpi_rs_length)(total_size +270						      acpi_rs_struct_option_length271						      (&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 the280			 * 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_length289						      (&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_length437 *438 * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream439 *              aml_buffer_length   - Size of aml_buffer440 *              size_needed         - Where the size needed is returned441 *442 * RETURN:      Status443 *444 * DESCRIPTION: Takes an external resource byte stream and calculates the size445 *              buffer needed to hold the corresponding internal resource446 *              descriptor linked list.447 *448 ******************************************************************************/449 450acpi_status451acpi_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_buffer,478					      &resource_index);479		if (ACPI_FAILURE(status)) {480			/*481			 * Exit on failure. Cannot continue because the descriptor length482			 * 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_buffer);492		minimum_aml_resource_length =493		    acpi_gbl_resource_aml_sizes[resource_index];494 495		/*496		 * Augment the size for descriptors with optional497		 * and/or variable length fields498		 */499		extra_struct_bytes = 0;500		buffer =501		    aml_buffer + acpi_ut_get_resource_header_length(aml_buffer);502 503		switch (acpi_ut_get_resource_type(aml_buffer)) {504		case ACPI_RESOURCE_NAME_IRQ:505			/*506			 * IRQ Resource:507			 * Get the number of bits set in the 16-bit IRQ mask508			 */509			ACPI_MOVE_16_TO_16(&temp16, buffer);510			extra_struct_bytes = acpi_rs_count_set_bits(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 mask517			 */518			extra_struct_bytes = acpi_rs_count_set_bits(*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 bytes526			 */527			extra_struct_bytes = resource_length;528 529			/*530			 * There is already one byte included in the minimum531			 * 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 exit542			 */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_source551			 */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 additional561			 * interrupt. Note: at least one interrupt is required and is562			 * 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 -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_serialbus614				    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_sizes620				    [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 structs685		 *686		 * Important: Round the size up for the appropriate alignment. This687		 * is a requirement on IA64.688		 */689		if (acpi_ut_get_resource_type(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_sizes700			    [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 length718		 * contained in the resource descriptor header719		 */720		aml_buffer += acpi_ut_get_descriptor_length(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_length731 *732 * PARAMETERS:  package_object          - Pointer to the package object733 *              buffer_size_needed      - u32 pointer of the size buffer734 *                                        needed to properly return the735 *                                        parsed data736 *737 * RETURN:      Status738 *739 * DESCRIPTION: Given a package representing a PCI routing table, this740 *              calculates the size of the corresponding linked list of741 *              descriptions.742 *743 ******************************************************************************/744 745acpi_status746acpi_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 the765	 * 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 and770	 * 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 the789		 * four IRQ elements: Address, Pin, Source and source_index790		 */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.count799		     && !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 the823				 * terminating NULL, add 1824				 */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((*sub_object_list)->reference.node);830			}831		} else {832			/*833			 * If no name was found, then this is a NULL, which is834			 * 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 a850	 * NULL terminator851	 */852	*buffer_size_needed =853	    temp_size_needed + sizeof(struct acpi_pci_routing_table);854	return_ACPI_STATUS(AE_OK);855}856