X-Git-Url: http://www.aleph1.co.uk/gitweb/?p=yaffs2.git;a=blobdiff_plain;f=yaffs_packedtags2.c;h=e420f95da1918ae0738568ec263a731c9e8f9eee;hp=97668dc7dc4be19b6a3d8d8e897993585aac249a;hb=457fb8efdcd9b61c657b8b03b942f048eaa5168c;hpb=37fd9ec3587b5c4d497a7682522a9adfab682e51

diff --git a/yaffs_packedtags2.c b/yaffs_packedtags2.c
index 97668dc..e420f95 100644
--- a/yaffs_packedtags2.c
+++ b/yaffs_packedtags2.c
@@ -1,60 +1,182 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2007 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_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
 
-static void yaffs_DumpPackedTags2(const yaffs_PackedTags2 *pt)
+#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));
+	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)
+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));
-	  
+	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, const 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;
-	
+
+	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;
+		}
+
+		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;
+		}
+	}
+
 	yaffs_DumpPackedTags2(pt);
 	yaffs_DumpTags2(t);
-	
-	yaffs_ECCCalculateOther((unsigned char *)&pt->t,sizeof(yaffs_PackedTags2TagsPart),&pt->ecc);
-	
+
+#ifndef YAFFS_IGNORE_TAGS_ECC
+	{
+		yaffs_ECCCalculateOther((unsigned char *)&pt->t,
+					sizeof(yaffs_PackedTags2TagsPart),
+					&pt->ecc);
+	}
+#endif
 }
 
-void yaffs_UnpackTags2(yaffs_ExtendedTags *t, const yaffs_PackedTags2 *pt)
+void yaffs_UnpackTags2(yaffs_ExtendedTags * t, yaffs_PackedTags2 * pt)
 {
 
-	
-	if(pt->t.sequenceNumber == 0xFFFFFFFF)
-	{
-		memset(t,0,sizeof(yaffs_ExtendedTags));
-		
-	}
-	else
-	{
-		// 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);
+	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 = YAFFS_ECC_RESULT_NO_ERROR;
+		}
+#else
+		{
+			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:
+					t->eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+					break;
+				case 1:
+					t->eccResult = YAFFS_ECC_RESULT_FIXED;
+					break;
+				case -1:
+					t->eccResult = YAFFS_ECC_RESULT_UNFIXED;
+					break;
+				default:
+					t->eccResult = YAFFS_ECC_RESULT_UNKNOWN;
+			}
+		}
+#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);
 
 }
-