+/*
+ * YAFFS: Yet another FFS. A NAND-flash specific file system.
+ *
+ * yaffs_packedtags2.c: Tags packing for YAFFS2
+ *
+ * Copyright (C) 2002 Aleph One Ltd.
+ *
+ * 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 Lesser General Public License
+ * version 2.1 as published by the Free Software Foundation.
+ */
+
#include "yaffs_packedtags2.h"
#include "yportenv.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_DumpPackedTags2(const yaffs_PackedTags2 * pt)
+{
+ T(YAFFS_TRACE_MTD,
+ (TSTR("packed tags obj %d chunk %d byte %d seq %d" TENDSTR),
+ pt->t.objectId, pt->t.chunkId, pt->t.byteCount,
+ pt->t.sequenceNumber));
+}
+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_PackTags2(yaffs_PackedTags2 *pt, yaffs_ExtendedTags *t)
+void yaffs_PackTags2(yaffs_PackedTags2 * pt, const yaffs_ExtendedTags * t)
{
pt->t.chunkId = t->chunkId;
pt->t.sequenceNumber = t->sequenceNumber;
pt->t.byteCount = t->byteCount;
pt->t.objectId = t->objectId;
-
- yaffs_ECCCalculateOther((unsigned char *)&pt->t,sizeof(yaffs_PackedTags2TagsPart),&pt->ecc);
-
-}
-void yaffs_UnpackTags2(yaffs_ExtendedTags *t, yaffs_PackedTags2 *pt)
-{
+ if (t->chunkId == 0 && t->extraHeaderInfoAvailable) {
+ /* Store the extra header info instead */
+ /* We save the parent object in the chunkId */
+ pt->t.chunkId = EXTRA_HEADER_INFO_FLAG
+ | t->extraParentObjectId;
+ if (t->extraIsShrinkHeader) {
+ pt->t.chunkId |= EXTRA_SHRINK_FLAG;
+ }
+ if (t->extraShadows) {
+ pt->t.chunkId |= EXTRA_SHADOWS_FLAG;
+ }
-
- if(pt->t.sequenceNumber == 0xFFFFFFFF)
- {
- memset(t,0,sizeof(yaffs_ExtendedTags));
-
+ pt->t.objectId &= ~EXTRA_OBJECT_TYPE_MASK;
+ pt->t.objectId |=
+ (t->extraObjectType << EXTRA_OBJECT_TYPE_SHIFT);
+
+ if (t->extraObjectType == YAFFS_OBJECT_TYPE_HARDLINK) {
+ pt->t.byteCount = t->extraEquivalentObjectId;
+ } else if (t->extraObjectType == YAFFS_OBJECT_TYPE_FILE) {
+ pt->t.byteCount = t->extraFileLength;
+ } else {
+ pt->t.byteCount = 0;
+ }
}
- else
+
+ yaffs_DumpPackedTags2(pt);
+ yaffs_DumpTags2(t);
+
+#ifndef YAFFS_IGNORE_TAGS_ECC
{
- // Page is in use
- yaffs_ECCOther ecc;
- yaffs_ECCCalculateOther((unsigned char *)&pt->t,sizeof(yaffs_PackedTags2TagsPart),&ecc);
- t->eccResult = yaffs_ECCCorrectOther((unsigned char *)&pt->t,sizeof(yaffs_PackedTags2TagsPart),&pt->ecc,&ecc);
+ yaffs_ECCCalculateOther((unsigned char *)&pt->t,
+ sizeof(yaffs_PackedTags2TagsPart),
+ &pt->ecc);
+ }
+#endif
+}
+
+void yaffs_UnpackTags2(yaffs_ExtendedTags * t, yaffs_PackedTags2 * pt)
+{
+
+ memset(t, 0, sizeof(yaffs_ExtendedTags));
+
+ yaffs_InitialiseTags(t);
+
+ if (pt->t.sequenceNumber != 0xFFFFFFFF) {
+ /* Page is in use */
+#ifdef YAFFS_IGNORE_TAGS_ECC
+ {
+ t->eccResult = 0;
+ }
+#else
+ {
+ yaffs_ECCOther ecc;
+ yaffs_ECCCalculateOther((unsigned char *)&pt->t,
+ sizeof
+ (yaffs_PackedTags2TagsPart),
+ &ecc);
+ t->eccResult =
+ yaffs_ECCCorrectOther((unsigned char *)&pt->t,
+ sizeof
+ (yaffs_PackedTags2TagsPart),
+ &pt->ecc, &ecc);
+ }
+#endif
t->blockBad = 0;
t->chunkUsed = 1;
t->objectId = pt->t.objectId;
- t->chunkId = pt->t.chunkId;
+ t->chunkId = pt->t.chunkId;
t->byteCount = pt->t.byteCount;
t->chunkDeleted = 0;
t->serialNumber = 0;
t->sequenceNumber = pt->t.sequenceNumber;
+
+ /* Do extra header info stuff */
+
+ if (pt->t.chunkId & EXTRA_HEADER_INFO_FLAG) {
+ t->chunkId = 0;
+ t->byteCount = 0;
+
+ t->extraHeaderInfoAvailable = 1;
+ t->extraParentObjectId =
+ pt->t.chunkId & (~(ALL_EXTRA_FLAGS));
+ t->extraIsShrinkHeader =
+ (pt->t.chunkId & EXTRA_SHRINK_FLAG) ? 1 : 0;
+ t->extraShadows =
+ (pt->t.chunkId & EXTRA_SHADOWS_FLAG) ? 1 : 0;
+ t->extraObjectType =
+ pt->t.objectId >> EXTRA_OBJECT_TYPE_SHIFT;
+ t->objectId &= ~EXTRA_OBJECT_TYPE_MASK;
+
+ if (t->extraObjectType == YAFFS_OBJECT_TYPE_HARDLINK) {
+ t->extraEquivalentObjectId = pt->t.byteCount;
+ } else {
+ t->extraFileLength = pt->t.byteCount;
+ }
+ }
}
-}
+ yaffs_DumpPackedTags2(pt);
+ yaffs_DumpTags2(t);
+
+}
projects / yaffs2.git / blobdiff