X-Git-Url: http://www.aleph1.co.uk/gitweb/?p=yaffs2.git;a=blobdiff_plain;f=yaffs_packedtags2.c;h=957ed8bf0e5b19ee73fb36a72beda062a36175d9;hp=01e23a7dfb7de3647ec88b4affa3cb6215f4f728;hb=40c386c7a14ebfa8afc14562f3b33a416831b26d;hpb=6d328375504ad23f4731f17fcf12eeeb26a55f21

diff --git a/yaffs_packedtags2.c b/yaffs_packedtags2.c
index 01e23a7..957ed8b 100644
--- a/yaffs_packedtags2.c
+++ b/yaffs_packedtags2.c
@@ -1,143 +1,204 @@
 /*
- * YAFFS: Yet another FFS. A NAND-flash specific file system. 
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
- * yaffs_packedtags2.c: Tags packing for YAFFS2
- *
- * Copyright (C) 2002 Aleph One Ltd.
+ * 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 Lesser General Public License
- * version 2.1 as published by the Free Software Foundation.
+ * 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.
+ */
 
-// 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
+/* Extra flags applied to chunkId */
 
 #define EXTRA_HEADER_INFO_FLAG	0x80000000
 #define EXTRA_SHRINK_FLAG	0x40000000
-#define EXTRA_SPARE_FLAGS	0x30000000
+#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.
+/* 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)
+static void yaffs_DumpPackedTags2TagsPart(const yaffs_PackedTags2TagsPart * ptt)
 {
-	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),
+	   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)
+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_PackTags2TagsPart(yaffs_PackedTags2TagsPart * ptt, 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
-		pt->t.chunkId = EXTRA_HEADER_INFO_FLAG | t->extraParentObjectId; // We save the parent object in the chunkId
-		if(t->extraIsShrinkHeader) 
-		{
-		    pt->t.chunkId |= EXTRA_SHRINK_FLAG;
+	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;
 		}
-		
-		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;
+		if (t->extraShadows) {
+			ptt->chunkId |= EXTRA_SHADOWS_FLAG;
 		}
-		else if(t->extraObjectType == YAFFS_OBJECT_TYPE_FILE)
-		{
-		   pt->t.byteCount = t->extraFileLength;
-		}
-		else
-		{
-		   pt->t.byteCount = 0;
+
+		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_DumpPackedTags2(pt);
+
+	yaffs_DumpPackedTags2TagsPart(ptt);
 	yaffs_DumpTags2(t);
-	
-	yaffs_ECCCalculateOther((unsigned char *)&pt->t,sizeof(yaffs_PackedTags2TagsPart),&pt->ecc);
-	
 }
 
-void yaffs_UnpackTags2(yaffs_ExtendedTags *t, yaffs_PackedTags2 *pt)
+
+void yaffs_PackTags2(yaffs_PackedTags2 * pt, const yaffs_ExtendedTags * t)
 {
+	yaffs_PackTags2TagsPart(&pt->t,t);
 
-	
-	memset(t,0,sizeof(yaffs_ExtendedTags));
-	
-	yaffs_InitialiseTags(t);
-	
-	if(pt->t.sequenceNumber != 0xFFFFFFFF)
+#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_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 = pt->t.objectId;
-		t->chunkId =  pt->t.chunkId;
-		t->byteCount = pt->t.byteCount;
+		t->objectId = ptt->objectId;
+		t->chunkId = ptt->chunkId;
+		t->byteCount = ptt->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->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 = pt->t.chunkId & (~(ALL_EXTRA_FLAGS));
-			t->extraIsShrinkHeader =  (pt->t.chunkId & EXTRA_SHRINK_FLAG) ? 1 : 0;
-			t->extraObjectType = pt->t.objectId >> EXTRA_OBJECT_TYPE_SHIFT;
+			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 = pt->t.byteCount;
+
+			if (t->extraObjectType == YAFFS_OBJECT_TYPE_HARDLINK) {
+				t->extraEquivalentObjectId = ptt->byteCount;
+			} else {
+				t->extraFileLength = ptt->byteCount;
 			}
-			else 
-			{
-			    t->extraFileLength = pt->t.byteCount;
+		}
+	}
+
+	yaffs_DumpPackedTags2TagsPart(ptt);
+	yaffs_DumpTags2(t);
+
+}
+
+
+void yaffs_UnpackTags2(yaffs_ExtendedTags * t, yaffs_PackedTags2 * pt)
+{
+
+	yaffs_UnpackTags2TagsPart(t,&pt->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
 	}
 
 	yaffs_DumpPackedTags2(pt);