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/*
* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
*
* Copyright (C) 2002-2010 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning <charles@aleph1.co.uk>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include "yaffs_packedtags2.h"
#include "yportenv.h"
#include "yaffs_trace.h"
#include "yaffs_tagsvalidity.h"
/* This code packs a set of extended tags into a binary structure for
* NAND storage
*/
/* Some of the information is "extra" struff which can be packed in to
* speed scanning
* This is defined by having the EXTRA_HEADER_INFO_FLAG set.
*/
/* Extra flags applied to chunkId */
#define EXTRA_HEADER_INFO_FLAG 0x80000000
#define EXTRA_SHRINK_FLAG 0x40000000
#define EXTRA_SHADOWS_FLAG 0x20000000
#define EXTRA_SPARE_FLAGS 0x10000000
#define ALL_EXTRA_FLAGS 0xF0000000
/* Also, the top 4 bits of the object Id are set to the object type. */
#define EXTRA_OBJECT_TYPE_SHIFT (28)
#define EXTRA_OBJECT_TYPE_MASK ((0x0F) << EXTRA_OBJECT_TYPE_SHIFT)
static void yaffs_DumpPackedTags2TagsPart(const yaffs_PackedTags2TagsPart *ptt)
{
T(YAFFS_TRACE_MTD,
(TSTR("packed tags obj %d chunk %d byte %d seq %d" TENDSTR),
ptt->objectId, ptt->chunkId, ptt->byteCount,
ptt->sequenceNumber));
}
static void yaffs_DumpPackedTags2(const yaffs_PackedTags2 *pt)
{
yaffs_DumpPackedTags2TagsPart(&pt->t);
}
static void yaffs_DumpTags2(const yaffs_ExtendedTags *t)
{
T(YAFFS_TRACE_MTD,
(TSTR
("ext.tags eccres %d blkbad %d chused %d obj %d chunk%d byte %d del %d ser %d seq %d"
TENDSTR), t->eccResult, t->blockBad, t->chunkUsed, t->objectId,
t->chunkId, t->byteCount, t->chunkDeleted, t->serialNumber,
t->sequenceNumber));
}
void yaffs_PackTags2TagsPart(yaffs_PackedTags2TagsPart *ptt,
const yaffs_ExtendedTags *t)
{
ptt->chunkId = t->chunkId;
ptt->sequenceNumber = t->sequenceNumber;
ptt->byteCount = t->byteCount;
ptt->objectId = t->objectId;
if (t->chunkId == 0 && t->extraHeaderInfoAvailable) {
/* Store the extra header info instead */
/* We save the parent object in the chunkId */
ptt->chunkId = EXTRA_HEADER_INFO_FLAG
| t->extraParentObjectId;
if (t->extraIsShrinkHeader)
ptt->chunkId |= EXTRA_SHRINK_FLAG;
if (t->extraShadows)
ptt->chunkId |= EXTRA_SHADOWS_FLAG;
ptt->objectId &= ~EXTRA_OBJECT_TYPE_MASK;
ptt->objectId |=
(t->extraObjectType << EXTRA_OBJECT_TYPE_SHIFT);
if (t->extraObjectType == YAFFS_OBJECT_TYPE_HARDLINK)
ptt->byteCount = t->extraEquivalentObjectId;
else if (t->extraObjectType == YAFFS_OBJECT_TYPE_FILE)
ptt->byteCount = t->extraFileLength;
else
ptt->byteCount = 0;
}
yaffs_DumpPackedTags2TagsPart(ptt);
yaffs_DumpTags2(t);
}
void yaffs_PackTags2(yaffs_PackedTags2 *pt, const yaffs_ExtendedTags *t, int tagsECC)
{
yaffs_PackTags2TagsPart(&pt->t, t);
if(tagsECC)
yaffs_ECCCalculateOther((unsigned char *)&pt->t,
sizeof(yaffs_PackedTags2TagsPart),
&pt->ecc);
}
void yaffs_UnpackTags2TagsPart(yaffs_ExtendedTags *t,
yaffs_PackedTags2TagsPart *ptt)
{
memset(t, 0, sizeof(yaffs_ExtendedTags));
yaffs_InitialiseTags(t);
if (ptt->sequenceNumber != 0xFFFFFFFF) {
t->blockBad = 0;
t->chunkUsed = 1;
t->objectId = ptt->objectId;
t->chunkId = ptt->chunkId;
t->byteCount = ptt->byteCount;
t->chunkDeleted = 0;
t->serialNumber = 0;
t->sequenceNumber = ptt->sequenceNumber;
/* Do extra header info stuff */
if (ptt->chunkId & EXTRA_HEADER_INFO_FLAG) {
t->chunkId = 0;
t->byteCount = 0;
t->extraHeaderInfoAvailable = 1;
t->extraParentObjectId =
ptt->chunkId & (~(ALL_EXTRA_FLAGS));
t->extraIsShrinkHeader =
(ptt->chunkId & EXTRA_SHRINK_FLAG) ? 1 : 0;
t->extraShadows =
(ptt->chunkId & EXTRA_SHADOWS_FLAG) ? 1 : 0;
t->extraObjectType =
ptt->objectId >> EXTRA_OBJECT_TYPE_SHIFT;
t->objectId &= ~EXTRA_OBJECT_TYPE_MASK;
if (t->extraObjectType == YAFFS_OBJECT_TYPE_HARDLINK)
t->extraEquivalentObjectId = ptt->byteCount;
else
t->extraFileLength = ptt->byteCount;
}
}
yaffs_DumpPackedTags2TagsPart(ptt);
yaffs_DumpTags2(t);
}
void yaffs_UnpackTags2(yaffs_ExtendedTags *t, yaffs_PackedTags2 *pt, int tagsECC)
{
yaffs_ECCResult eccResult = YAFFS_ECC_RESULT_NO_ERROR;
if (pt->t.sequenceNumber != 0xFFFFFFFF &&
tagsECC){
/* Chunk is in use and we need to do ECC */
yaffs_ECCOther ecc;
int result;
yaffs_ECCCalculateOther((unsigned char *)&pt->t,
sizeof(yaffs_PackedTags2TagsPart),
&ecc);
result = yaffs_ECCCorrectOther((unsigned char *)&pt->t,
sizeof(yaffs_PackedTags2TagsPart),
&pt->ecc, &ecc);
switch (result) {
case 0:
eccResult = YAFFS_ECC_RESULT_NO_ERROR;
break;
case 1:
eccResult = YAFFS_ECC_RESULT_FIXED;
break;
case -1:
eccResult = YAFFS_ECC_RESULT_UNFIXED;
break;
default:
eccResult = YAFFS_ECC_RESULT_UNKNOWN;
}
}
yaffs_UnpackTags2TagsPart(t, &pt->t);
t->eccResult = eccResult;
yaffs_DumpPackedTags2(pt);
yaffs_DumpTags2(t);
}
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