summaryrefslogtreecommitdiffstats
path: root/fs/yaffs2/yaffs_packedtags2.c
blob: 467d5ac1be34d53b5c62cf3945d6449d725216ca (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/*
 * 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.
 */

/* XXX U-BOOT XXX */
#include <common.h>

#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, 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);

#ifndef YAFFS_IGNORE_TAGS_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 = 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->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);

}
OpenPOWER on IntegriCloud