2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
4 * Copyright (C) 2002-2007 Aleph One Ltd.
5 * for Toby Churchill Ltd and Brightstar Engineering
7 * Created by Charles Manning <charles@aleph1.co.uk>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #include "yaffs_packedtags2.h"
16 #include "yaffs_tagsvalidity.h"
18 /* This code packs a set of extended tags into a binary structure for
22 /* Some of the information is "extra" struff which can be packed in to
24 * This is defined by having the EXTRA_HEADER_INFO_FLAG set.
27 /* Extra flags applied to chunkId */
29 #define EXTRA_HEADER_INFO_FLAG 0x80000000
30 #define EXTRA_SHRINK_FLAG 0x40000000
31 #define EXTRA_SHADOWS_FLAG 0x20000000
32 #define EXTRA_SPARE_FLAGS 0x10000000
34 #define ALL_EXTRA_FLAGS 0xF0000000
36 /* Also, the top 4 bits of the object Id are set to the object type. */
37 #define EXTRA_OBJECT_TYPE_SHIFT (28)
38 #define EXTRA_OBJECT_TYPE_MASK ((0x0F) << EXTRA_OBJECT_TYPE_SHIFT)
40 static void yaffs_DumpPackedTags2(const yaffs_PackedTags2
* pt
)
43 (TSTR("packed tags obj %d chunk %d byte %d seq %d" TENDSTR
),
44 pt
->t
.objectId
, pt
->t
.chunkId
, pt
->t
.byteCount
,
45 pt
->t
.sequenceNumber
));
48 static void yaffs_DumpTags2(const yaffs_ExtendedTags
* t
)
52 ("ext.tags eccres %d blkbad %d chused %d obj %d chunk%d byte "
53 "%d del %d ser %d seq %d"
54 TENDSTR
), t
->eccResult
, t
->blockBad
, t
->chunkUsed
, t
->objectId
,
55 t
->chunkId
, t
->byteCount
, t
->chunkDeleted
, t
->serialNumber
,
60 void yaffs_PackTags2(yaffs_PackedTags2
* pt
, const yaffs_ExtendedTags
* t
)
62 pt
->t
.chunkId
= t
->chunkId
;
63 pt
->t
.sequenceNumber
= t
->sequenceNumber
;
64 pt
->t
.byteCount
= t
->byteCount
;
65 pt
->t
.objectId
= t
->objectId
;
67 if (t
->chunkId
== 0 && t
->extraHeaderInfoAvailable
) {
68 /* Store the extra header info instead */
69 /* We save the parent object in the chunkId */
70 pt
->t
.chunkId
= EXTRA_HEADER_INFO_FLAG
71 | t
->extraParentObjectId
;
72 if (t
->extraIsShrinkHeader
) {
73 pt
->t
.chunkId
|= EXTRA_SHRINK_FLAG
;
75 if (t
->extraShadows
) {
76 pt
->t
.chunkId
|= EXTRA_SHADOWS_FLAG
;
79 pt
->t
.objectId
&= ~EXTRA_OBJECT_TYPE_MASK
;
81 (t
->extraObjectType
<< EXTRA_OBJECT_TYPE_SHIFT
);
83 if (t
->extraObjectType
== YAFFS_OBJECT_TYPE_HARDLINK
) {
84 pt
->t
.byteCount
= t
->extraEquivalentObjectId
;
85 } else if (t
->extraObjectType
== YAFFS_OBJECT_TYPE_FILE
) {
86 pt
->t
.byteCount
= t
->extraFileLength
;
92 yaffs_DumpPackedTags2(pt
);
95 #ifndef YAFFS_IGNORE_TAGS_ECC
97 yaffs_ECCCalculateOther((unsigned char *)&pt
->t
,
98 sizeof(yaffs_PackedTags2TagsPart
),
104 void yaffs_UnpackTags2(yaffs_ExtendedTags
* t
, yaffs_PackedTags2
* pt
)
107 memset(t
, 0, sizeof(yaffs_ExtendedTags
));
109 yaffs_InitialiseTags(t
);
111 if (pt
->t
.sequenceNumber
!= 0xFFFFFFFF) {
113 #ifdef YAFFS_IGNORE_TAGS_ECC
115 t
->eccResult
= YAFFS_ECC_RESULT_NO_ERROR
;
121 yaffs_ECCCalculateOther((unsigned char *)&pt
->t
,
123 (yaffs_PackedTags2TagsPart
),
126 yaffs_ECCCorrectOther((unsigned char *)&pt
->t
,
128 (yaffs_PackedTags2TagsPart
),
132 t
->eccResult
= YAFFS_ECC_RESULT_NO_ERROR
;
135 t
->eccResult
= YAFFS_ECC_RESULT_FIXED
;
138 t
->eccResult
= YAFFS_ECC_RESULT_UNFIXED
;
141 t
->eccResult
= YAFFS_ECC_RESULT_UNKNOWN
;
147 t
->objectId
= pt
->t
.objectId
;
148 t
->chunkId
= pt
->t
.chunkId
;
149 t
->byteCount
= pt
->t
.byteCount
;
152 t
->sequenceNumber
= pt
->t
.sequenceNumber
;
154 /* Do extra header info stuff */
156 if (pt
->t
.chunkId
& EXTRA_HEADER_INFO_FLAG
) {
160 t
->extraHeaderInfoAvailable
= 1;
161 t
->extraParentObjectId
=
162 pt
->t
.chunkId
& (~(ALL_EXTRA_FLAGS
));
163 t
->extraIsShrinkHeader
=
164 (pt
->t
.chunkId
& EXTRA_SHRINK_FLAG
) ? 1 : 0;
166 (pt
->t
.chunkId
& EXTRA_SHADOWS_FLAG
) ? 1 : 0;
168 pt
->t
.objectId
>> EXTRA_OBJECT_TYPE_SHIFT
;
169 t
->objectId
&= ~EXTRA_OBJECT_TYPE_MASK
;
171 if (t
->extraObjectType
== YAFFS_OBJECT_TYPE_HARDLINK
) {
172 t
->extraEquivalentObjectId
= pt
->t
.byteCount
;
174 t
->extraFileLength
= pt
->t
.byteCount
;
179 yaffs_DumpPackedTags2(pt
);