+++ /dev/null
-/*++\r
-\r
-Copyright (c) 2006, Intel Corporation \r
-All rights reserved. This program and the accompanying materials \r
-are licensed and made available under the terms and conditions of the BSD License \r
-which accompanies this distribution. The full text of the license may be found at \r
-http://opensource.org/licenses/bsd-license.php \r
- \r
-THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r
-WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
-\r
-Module Name:\r
-\r
- DataHub.c\r
-\r
-Abstract:\r
-\r
- This code produces the Data Hub protocol. It preloads the data hub\r
- with status information copied in from PEI HOBs.\r
- \r
- Only code that implements the Data Hub protocol should go in this file!\r
-\r
- The Term MTC stands for MonoTonicCounter. \r
-\r
- For more information please look at DataHub.doc\r
-\r
- NOTE: For extra security of the log GetNextDataRecord () could return a copy\r
- of the data record.\r
---*/\r
-\r
-#include "DataHub.h"\r
-\r
-CONST EFI_GUID gZeroGuid = { 0, 0, 0, { 0, 0, 0, 0, 0, 0, 0, 0 } };\r
-\r
-//\r
-// Worker functions private to this file\r
-//\r
-STATIC\r
-DATA_HUB_FILTER_DRIVER *\r
-FindFilterDriverByEvent (\r
- IN LIST_ENTRY *Head,\r
- IN EFI_EVENT Event\r
- );\r
-\r
-STATIC\r
-EFI_DATA_RECORD_HEADER *\r
-GetNextDataRecord (\r
- IN LIST_ENTRY *Head,\r
- IN UINT64 ClassFilter,\r
- IN OUT UINT64 *PtrCurrentMTC\r
- );\r
-\r
-STATIC\r
-EFI_STATUS\r
-EFIAPI\r
-DataHubLogData (\r
- IN EFI_DATA_HUB_PROTOCOL *This,\r
- IN EFI_GUID *DataRecordGuid,\r
- IN EFI_GUID *ProducerName,\r
- IN UINT64 DataRecordClass,\r
- IN VOID *RawData,\r
- IN UINT32 RawDataSize\r
- )\r
-/*++\r
-\r
-Routine Description:\r
-\r
- Log data record into the data logging hub\r
-\r
-Arguments:\r
-\r
- This - Protocol instance structure\r
-\r
- DataRecordGuid - GUID that defines record contents\r
-\r
- ProducerName - GUID that defines the name of the producer of the data\r
-\r
- DataRecordClass - Class that defines generic record type\r
-\r
- RawData - Data Log record as defined by DataRecordGuid\r
- \r
- RawDataSize - Size of Data Log data in bytes\r
-\r
-Returns: \r
-\r
- EFI_SUCCESS - If data was logged\r
-\r
- EFI_OUT_OF_RESOURCES - If data was not logged due to lack of system \r
- resources.\r
---*/\r
-{\r
- EFI_STATUS Status;\r
- DATA_HUB_INSTANCE *Private;\r
- EFI_DATA_ENTRY *LogEntry;\r
- UINT32 TotalSize;\r
- UINT32 RecordSize;\r
- EFI_DATA_RECORD_HEADER *Record;\r
- VOID *Raw;\r
- DATA_HUB_FILTER_DRIVER *FilterEntry;\r
- LIST_ENTRY *Link;\r
- LIST_ENTRY *Head;\r
-\r
- Private = DATA_HUB_INSTANCE_FROM_THIS (This);\r
-\r
- //\r
- // Combine the storage for the internal structs and a copy of the log record.\r
- // Record follows PrivateLogEntry. The consumer will be returned a pointer\r
- // to Record so we don't what it to be the thing that was allocated from\r
- // pool, so the consumer can't free an data record by mistake.\r
- //\r
- RecordSize = sizeof (EFI_DATA_RECORD_HEADER) + RawDataSize;\r
- TotalSize = sizeof (EFI_DATA_ENTRY) + RecordSize;\r
-\r
- //\r
- // The Logging action is the critical section, so it is locked.\r
- // The MTC asignment & update, time, and logging must be an\r
- // atomic operation, so use the lock.\r
- //\r
- Status = EfiAcquireLockOrFail (&Private->DataLock);\r
- if (EFI_ERROR (Status)) {\r
- //\r
- // Reentrancy detected so exit!\r
- //\r
- return Status;\r
- }\r
-\r
- LogEntry = AllocatePool (TotalSize);\r
-\r
- if (LogEntry == NULL) {\r
- EfiReleaseLock (&Private->DataLock);\r
- return EFI_OUT_OF_RESOURCES;\r
- }\r
-\r
- ZeroMem (LogEntry, TotalSize);\r
-\r
- Record = (EFI_DATA_RECORD_HEADER *) (LogEntry + 1);\r
- Raw = (VOID *) (Record + 1);\r
-\r
- //\r
- // Build Standard Log Header\r
- //\r
- Record->Version = EFI_DATA_RECORD_HEADER_VERSION;\r
- Record->HeaderSize = sizeof (EFI_DATA_RECORD_HEADER);\r
- Record->RecordSize = RecordSize;\r
- CopyMem (&Record->DataRecordGuid, DataRecordGuid, sizeof (EFI_GUID));\r
- CopyMem (&Record->ProducerName, ProducerName, sizeof (EFI_GUID));\r
- Record->DataRecordClass = DataRecordClass;\r
-\r
- Record->LogMonotonicCount = Private->GlobalMonotonicCount++;\r
-\r
- gRT->GetTime (&Record->LogTime, NULL);\r
-\r
- //\r
- // Insert log into the internal linked list.\r
- //\r
- LogEntry->Signature = EFI_DATA_ENTRY_SIGNATURE;\r
- LogEntry->Record = Record;\r
- LogEntry->RecordSize = sizeof (EFI_DATA_ENTRY) + RawDataSize;\r
- InsertTailList (&Private->DataListHead, &LogEntry->Link);\r
-\r
- CopyMem (Raw, RawData, RawDataSize);\r
-\r
- EfiReleaseLock (&Private->DataLock);\r
-\r
- //\r
- // Send Signal to all the filter drivers which are interested\r
- // in the record's class and guid.\r
- //\r
- Head = &Private->FilterDriverListHead;\r
- for (Link = Head->ForwardLink; Link != Head; Link = Link->ForwardLink) {\r
- FilterEntry = FILTER_ENTRY_FROM_LINK (Link);\r
- if (((FilterEntry->ClassFilter & DataRecordClass) != 0) &&\r
- (CompareGuid (&FilterEntry->FilterDataRecordGuid, &gZeroGuid) || \r
- CompareGuid (&FilterEntry->FilterDataRecordGuid, DataRecordGuid))) {\r
- gBS->SignalEvent (FilterEntry->Event);\r
- }\r
- }\r
-\r
- return EFI_SUCCESS;\r
-}\r
-\r
-STATIC\r
-EFI_STATUS\r
-EFIAPI\r
-DataHubGetNextRecord (\r
- IN EFI_DATA_HUB_PROTOCOL *This,\r
- IN OUT UINT64 *MonotonicCount,\r
- IN EFI_EVENT *FilterDriverEvent, OPTIONAL\r
- OUT EFI_DATA_RECORD_HEADER **Record\r
- )\r
-/*++\r
-\r
-Routine Description:\r
-\r
- Get a previously logged data record and the MonotonicCount for the next\r
- availible Record. This allows all records or all records later \r
- than a give MonotonicCount to be returned. If an optional FilterDriverEvent\r
- is passed in with a MonotonicCout of zero return the first record \r
- not yet read by the filter driver. If FilterDriverEvent is NULL and \r
- MonotonicCount is zero return the first data record.\r
-\r
-Arguments:\r
-\r
- This - The EFI_DATA_HUB_PROTOCOL instance.\r
- MonotonicCount - Specifies the Record to return. On input, zero means\r
- return the first record. On output, contains the next\r
- record to availible. Zero indicates no more records.\r
- FilterDriverEvent - If FilterDriverEvent is not passed in a MonotonicCount \r
- of zero, it means to return the first data record. \r
- If FilterDriverEvent is passed in, then a MonotonicCount \r
- of zero means to return the first data not yet read by \r
- FilterDriverEvent.\r
- Record - Returns a dynamically allocated memory buffer with a data \r
- record that matches MonotonicCount.\r
-\r
-Returns: \r
-\r
- EFI_SUCCESS - Data was returned in Record.\r
- EFI_INVALID_PARAMETER - FilterDriverEvent was passed in but does not exist.\r
- EFI_NOT_FOUND - MonotonicCount does not match any data record in the\r
- system. If a MonotonicCount of zero was passed in, then\r
- no data records exist in the system.\r
- EFI_OUT_OF_RESOURCES - Record was not returned due to lack of system resources.\r
-\r
---*/\r
-{\r
- DATA_HUB_INSTANCE *Private;\r
- DATA_HUB_FILTER_DRIVER *FilterDriver;\r
- UINT64 ClassFilter;\r
- UINT64 FilterMonotonicCount;\r
-\r
- Private = DATA_HUB_INSTANCE_FROM_THIS (This);\r
-\r
- FilterDriver = NULL;\r
- FilterMonotonicCount = 0;\r
- ClassFilter = EFI_DATA_RECORD_CLASS_DEBUG |\r
- EFI_DATA_RECORD_CLASS_ERROR |\r
- EFI_DATA_RECORD_CLASS_DATA |\r
- EFI_DATA_RECORD_CLASS_PROGRESS_CODE;\r
-\r
- if (FilterDriverEvent != NULL) {\r
- //\r
- // For events the beginning is the last unread record. This info is\r
- // stored in the instance structure, so we must look up the event\r
- // to get the data.\r
- //\r
- FilterDriver = FindFilterDriverByEvent (\r
- &Private->FilterDriverListHead,\r
- *FilterDriverEvent\r
- );\r
- if (FilterDriver == NULL) {\r
- return EFI_INVALID_PARAMETER;\r
- }\r
- //\r
- // Use the Class filter the event was created with.\r
- //\r
- ClassFilter = FilterDriver->ClassFilter;\r
-\r
- if (*MonotonicCount == 0) {\r
- //\r
- // Use the MTC from the Filter Driver.\r
- //\r
- FilterMonotonicCount = FilterDriver->GetNextMonotonicCount;\r
- if (FilterMonotonicCount != 0) {\r
- //\r
- // The GetNextMonotonicCount field remembers the last value from the previous time.\r
- // But we already processed this vaule, so we need to find the next one. So if\r
- // It is not the first time get the new record entry.\r
- //\r
- *Record = GetNextDataRecord (&Private->DataListHead, ClassFilter, &FilterMonotonicCount);\r
- *MonotonicCount = FilterMonotonicCount;\r
- if (FilterMonotonicCount == 0) {\r
- //\r
- // If there is no new record to get exit now.\r
- //\r
- return EFI_NOT_FOUND;\r
- }\r
- }\r
- }\r
- }\r
- //\r
- // Return the record\r
- //\r
- *Record = GetNextDataRecord (&Private->DataListHead, ClassFilter, MonotonicCount);\r
- if (*Record == NULL) {\r
- return EFI_NOT_FOUND;\r
- }\r
-\r
- if (FilterDriver != NULL) {\r
- //\r
- // If we have a filter driver update the records that have been read.\r
- // If MonotonicCount is zero No more reacords left.\r
- //\r
- if (*MonotonicCount == 0) {\r
- if (FilterMonotonicCount != 0) {\r
- //\r
- // Return the result of our extra GetNextDataRecord.\r
- //\r
- FilterDriver->GetNextMonotonicCount = FilterMonotonicCount;\r
- }\r
- } else {\r
- //\r
- // Point to next undread record\r
- //\r
- FilterDriver->GetNextMonotonicCount = *MonotonicCount;\r
- }\r
- }\r
-\r
- return EFI_SUCCESS;\r
-}\r
-\r
-STATIC\r
-EFI_STATUS\r
-EFIAPI\r
-DataHubRegisterFilterDriver (\r
- IN EFI_DATA_HUB_PROTOCOL * This,\r
- IN EFI_EVENT FilterEvent,\r
- IN EFI_TPL FilterTpl,\r
- IN UINT64 FilterClass,\r
- IN EFI_GUID * FilterDataRecordGuid OPTIONAL\r
- )\r
-/*++\r
-\r
-Routine Description:\r
-\r
- This function registers the data hub filter driver that is represented \r
- by FilterEvent. Only one instance of each FilterEvent can be registered.\r
- After the FilterEvent is registered, it will be signaled so it can sync \r
- with data records that have been recorded prior to the FilterEvent being \r
- registered.\r
- \r
-Arguments:\r
-\r
- This - The EFI_DATA_HUB_PROTOCOL instance.\r
- FilterEvent - The EFI_EVENT to signal whenever data that matches \r
- FilterClass is logged in the system.\r
- FilterTpl - The maximum EFI_TPL at which FilterEvent can be \r
- signaled. It is strongly recommended that you use the \r
- lowest EFI_TPL possible.\r
- FilterClass - FilterEvent will be signaled whenever a bit in \r
- EFI_DATA_RECORD_HEADER.DataRecordClass is also set in \r
- FilterClass. If FilterClass is zero, no class-based \r
- filtering will be performed.\r
- FilterDataRecordGuid - FilterEvent will be signaled whenever FilterDataRecordGuid \r
- matches EFI_DATA_RECORD_HEADER.DataRecordGuid. If \r
- FilterDataRecordGuid is NULL, then no GUID-based filtering \r
- will be performed. \r
-Returns: \r
-\r
- EFI_SUCCESS - The filter driver event was registered.\r
- EFI_ALREADY_STARTED - FilterEvent was previously registered and cannot be \r
- registered again.\r
- EFI_OUT_OF_RESOURCES - The filter driver event was not registered due to lack of \r
- system resources.\r
-\r
---*/\r
-{\r
- DATA_HUB_INSTANCE *Private;\r
- DATA_HUB_FILTER_DRIVER *FilterDriver;\r
-\r
- Private = DATA_HUB_INSTANCE_FROM_THIS (This);\r
-\r
- FilterDriver = (DATA_HUB_FILTER_DRIVER *) AllocateZeroPool (sizeof (DATA_HUB_FILTER_DRIVER));\r
- if (FilterDriver == NULL) {\r
- return EFI_OUT_OF_RESOURCES;\r
- }\r
- //\r
- // Initialize filter driver info\r
- //\r
- FilterDriver->Signature = EFI_DATA_HUB_FILTER_DRIVER_SIGNATURE;\r
- FilterDriver->Event = FilterEvent;\r
- FilterDriver->Tpl = FilterTpl;\r
- FilterDriver->GetNextMonotonicCount = 0;\r
- if (FilterClass == 0) {\r
- FilterDriver->ClassFilter = EFI_DATA_RECORD_CLASS_DEBUG |\r
- EFI_DATA_RECORD_CLASS_ERROR |\r
- EFI_DATA_RECORD_CLASS_DATA |\r
- EFI_DATA_RECORD_CLASS_PROGRESS_CODE;\r
- } else {\r
- FilterDriver->ClassFilter = FilterClass;\r
- }\r
-\r
- if (FilterDataRecordGuid != NULL) {\r
- CopyMem (&FilterDriver->FilterDataRecordGuid, FilterDataRecordGuid, sizeof (EFI_GUID));\r
- }\r
- //\r
- // Search for duplicate entries\r
- //\r
- if (FindFilterDriverByEvent (&Private->FilterDriverListHead, FilterEvent) != NULL) {\r
- FreePool (FilterDriver);\r
- return EFI_ALREADY_STARTED;\r
- }\r
- //\r
- // Make insertion an atomic operation with the lock.\r
- //\r
- EfiAcquireLock (&Private->DataLock);\r
- InsertTailList (&Private->FilterDriverListHead, &FilterDriver->Link);\r
- EfiReleaseLock (&Private->DataLock);\r
-\r
- //\r
- // Signal the Filter driver we just loaded so they will recieve all the\r
- // previous history. If we did not signal here we would have to wait until\r
- // the next data was logged to get the history. In a case where no next\r
- // data was logged we would never get synced up.\r
- //\r
- gBS->SignalEvent (FilterEvent);\r
-\r
- return EFI_SUCCESS;\r
-}\r
-\r
-STATIC\r
-EFI_STATUS\r
-EFIAPI\r
-DataHubUnregisterFilterDriver (\r
- IN EFI_DATA_HUB_PROTOCOL *This,\r
- IN EFI_EVENT FilterEvent\r
- )\r
-/*++\r
-\r
-Routine Description:\r
-\r
- Remove a Filter Driver, so it no longer gets called when data \r
- information is logged.\r
-\r
-Arguments:\r
-\r
- This - Protocol instance structure\r
-\r
- FilterEvent - Event that represents a filter driver that is to be \r
- Unregistered.\r
-\r
-Returns: \r
-\r
- EFI_SUCCESS - If FilterEvent was unregistered\r
-\r
- EFI_NOT_FOUND - If FilterEvent does not exist\r
-\r
---*/\r
-{\r
- DATA_HUB_INSTANCE *Private;\r
- DATA_HUB_FILTER_DRIVER *FilterDriver;\r
-\r
- Private = DATA_HUB_INSTANCE_FROM_THIS (This);\r
-\r
- //\r
- // Search for duplicate entries\r
- //\r
- FilterDriver = FindFilterDriverByEvent (\r
- &Private->FilterDriverListHead,\r
- FilterEvent\r
- );\r
- if (FilterDriver == NULL) {\r
- return EFI_NOT_FOUND;\r
- }\r
- //\r
- // Make removal an atomic operation with the lock\r
- //\r
- EfiAcquireLock (&Private->DataLock);\r
- RemoveEntryList (&FilterDriver->Link);\r
- EfiReleaseLock (&Private->DataLock);\r
-\r
- return EFI_SUCCESS;\r
-}\r
-//\r
-// STATIC Worker fucntions follow\r
-//\r
-STATIC\r
-DATA_HUB_FILTER_DRIVER *\r
-FindFilterDriverByEvent (\r
- IN LIST_ENTRY *Head,\r
- IN EFI_EVENT Event\r
- )\r
-/*++\r
-\r
-Routine Description:\r
- Search the Head list for a EFI_DATA_HUB_FILTER_DRIVER member that\r
- represents Event and return it.\r
-\r
-Arguments:\r
-\r
- Head - Head of dual linked list of EFI_DATA_HUB_FILTER_DRIVER\r
- structures.\r
-\r
- Event - Event to be search for in the Head list.\r
-\r
-Returns: \r
-\r
- EFI_DATA_HUB_FILTER_DRIVER - Returned if Event stored in the\r
- Head doubly linked list.\r
-\r
- NULL - If Event is not in the list\r
-\r
---*/\r
-{\r
- DATA_HUB_FILTER_DRIVER *FilterEntry;\r
- LIST_ENTRY *Link;\r
-\r
- for (Link = Head->ForwardLink; Link != Head; Link = Link->ForwardLink) {\r
- FilterEntry = FILTER_ENTRY_FROM_LINK (Link);\r
- if (FilterEntry->Event == Event) {\r
- return FilterEntry;\r
- }\r
- }\r
-\r
- return NULL;\r
-}\r
-\r
-STATIC\r
-EFI_DATA_RECORD_HEADER *\r
-GetNextDataRecord (\r
- IN LIST_ENTRY *Head,\r
- IN UINT64 ClassFilter,\r
- IN OUT UINT64 *PtrCurrentMTC\r
- )\r
-/*++\r
-\r
-Routine Description:\r
- Search the Head doubly linked list for the passed in MTC. Return the \r
- matching element in Head and the MTC on the next entry.\r
-\r
-Arguments:\r
-\r
- Head - Head of Data Log linked list.\r
-\r
- ClassFilter - Only match the MTC if it is in the same Class as the\r
- ClassFilter.\r
-\r
- PtrCurrentMTC - On IN contians MTC to search for. On OUT contians next\r
- MTC in the data log list or zero if at end of the list.\r
- \r
-Returns:\r
-\r
- EFI_DATA_LOG_ENTRY - Return pointer to data log data from Head list.\r
-\r
- NULL - If no data record exists.\r
-\r
---*/\r
-{\r
- EFI_DATA_ENTRY *LogEntry;\r
- LIST_ENTRY *Link;\r
- BOOLEAN ReturnFirstEntry;\r
- EFI_DATA_RECORD_HEADER *Record;\r
- EFI_DATA_ENTRY *NextLogEntry;\r
-\r
- //\r
- // If MonotonicCount == 0 just return the first one\r
- //\r
- ReturnFirstEntry = (BOOLEAN) (*PtrCurrentMTC == 0);\r
-\r
- Record = NULL;\r
- for (Link = Head->ForwardLink; Link != Head; Link = Link->ForwardLink) {\r
- LogEntry = DATA_ENTRY_FROM_LINK (Link);\r
- if ((LogEntry->Record->DataRecordClass & ClassFilter) == 0) {\r
- //\r
- // Skip any entry that does not have the correct ClassFilter\r
- //\r
- continue;\r
- }\r
-\r
- if ((LogEntry->Record->LogMonotonicCount == *PtrCurrentMTC) || ReturnFirstEntry) {\r
- //\r
- // Return record to the user\r
- //\r
- Record = LogEntry->Record;\r
-\r
- //\r
- // Calculate the next MTC value. If there is no next entry set\r
- // MTC to zero.\r
- //\r
- *PtrCurrentMTC = 0;\r
- for (Link = Link->ForwardLink; Link != Head; Link = Link->ForwardLink) {\r
- NextLogEntry = DATA_ENTRY_FROM_LINK (Link);\r
- if ((NextLogEntry->Record->DataRecordClass & ClassFilter) != 0) {\r
- //\r
- // Return the MTC of the next thing to search for if found\r
- //\r
- *PtrCurrentMTC = NextLogEntry->Record->LogMonotonicCount;\r
- break;\r
- }\r
- }\r
- //\r
- // Record found exit loop and return\r
- //\r
- break;\r
- }\r
- }\r
-\r
- return Record;\r
-}\r
-//\r
-// Module Global:\r
-// Since this driver will only ever produce one instance of the Logging Hub\r
-// protocol you are not required to dynamically allocate the PrivateData.\r
-//\r
-DATA_HUB_INSTANCE mPrivateData;\r
-\r
-EFI_STATUS\r
-EFIAPI\r
-DataHubInstall (\r
- IN EFI_HANDLE ImageHandle,\r
- IN EFI_SYSTEM_TABLE *SystemTable\r
- )\r
-/*++\r
-\r
-Routine Description:\r
- Install Driver to produce Data Hub protocol. \r
-\r
-Arguments:\r
- (Standard EFI Image entry - EFI_IMAGE_ENTRY_POINT)\r
-\r
-Returns: \r
-\r
- EFI_SUCCESS - Logging Hub protocol installed\r
-\r
- Other - No protocol installed, unload driver.\r
-\r
---*/\r
-{\r
- EFI_STATUS Status;\r
- UINT32 HighMontonicCount;\r
-\r
- mPrivateData.Signature = DATA_HUB_INSTANCE_SIGNATURE;\r
- mPrivateData.DataHub.LogData = DataHubLogData;\r
- mPrivateData.DataHub.GetNextRecord = DataHubGetNextRecord;\r
- mPrivateData.DataHub.RegisterFilterDriver = DataHubRegisterFilterDriver;\r
- mPrivateData.DataHub.UnregisterFilterDriver = DataHubUnregisterFilterDriver;\r
-\r
- //\r
- // Initialize Private Data in CORE_LOGGING_HUB_INSTANCE that is\r
- // required by this protocol\r
- //\r
- InitializeListHead (&mPrivateData.DataListHead);\r
- InitializeListHead (&mPrivateData.FilterDriverListHead);\r
-\r
- EfiInitializeLock (&mPrivateData.DataLock, TPL_NOTIFY);\r
-\r
- //\r
- // Make sure we get a bigger MTC number on every boot!\r
- //\r
- Status = gRT->GetNextHighMonotonicCount (&HighMontonicCount);\r
- if (EFI_ERROR (Status)) {\r
- //\r
- // if system service fails pick a sane value.\r
- //\r
- mPrivateData.GlobalMonotonicCount = 0;\r
- } else {\r
- mPrivateData.GlobalMonotonicCount = LShiftU64 ((UINT64) HighMontonicCount, 32);\r
- }\r
- //\r
- // Make a new handle and install the protocol\r
- //\r
- mPrivateData.Handle = NULL;\r
- Status = gBS->InstallProtocolInterface (\r
- &mPrivateData.Handle,\r
- &gEfiDataHubProtocolGuid,\r
- EFI_NATIVE_INTERFACE,\r
- &mPrivateData.DataHub\r
- );\r
- return Status;\r
-}\r
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