2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
4 * Copyright (C) 2002-2010 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_trace.h"
17 #include "yaffs_tagsvalidity.h"
19 /* This code packs a set of extended tags into a binary structure for
23 /* Some of the information is "extra" struff which can be packed in to
25 * This is defined by having the EXTRA_HEADER_INFO_FLAG set.
28 /* Extra flags applied to chunk_id */
30 #define EXTRA_HEADER_INFO_FLAG 0x80000000
31 #define EXTRA_SHRINK_FLAG 0x40000000
32 #define EXTRA_SHADOWS_FLAG 0x20000000
33 #define EXTRA_SPARE_FLAGS 0x10000000
35 #define ALL_EXTRA_FLAGS 0xF0000000
37 /* Also, the top 4 bits of the object Id are set to the object type. */
38 #define EXTRA_OBJECT_TYPE_SHIFT (28)
39 #define EXTRA_OBJECT_TYPE_MASK ((0x0F) << EXTRA_OBJECT_TYPE_SHIFT)
41 static void yaffs_dump_packed_tags2_tags_only(const struct
42 yaffs_packed_tags2_tags_only *ptt)
44 yaffs_trace(YAFFS_TRACE_MTD,
45 "packed tags obj %d chunk %d byte %d seq %d",
46 ptt->obj_id, ptt->chunk_id, ptt->n_bytes, ptt->seq_number);
49 static void yaffs_dump_packed_tags2(const struct yaffs_packed_tags2 *pt)
51 yaffs_dump_packed_tags2_tags_only(&pt->t);
54 static void yaffs_dump_tags2(const struct yaffs_ext_tags *t)
56 yaffs_trace(YAFFS_TRACE_MTD,
57 "ext.tags eccres %d blkbad %d chused %d obj %d chunk%d byte %d del %d ser %d seq %d",
58 t->ecc_result, t->block_bad, t->chunk_used, t->obj_id,
59 t->chunk_id, t->n_bytes, t->is_deleted, t->serial_number,
64 void yaffs_pack_tags2_tags_only(struct yaffs_packed_tags2_tags_only *ptt,
65 const struct yaffs_ext_tags *t)
67 ptt->chunk_id = t->chunk_id;
68 ptt->seq_number = t->seq_number;
69 ptt->n_bytes = t->n_bytes;
70 ptt->obj_id = t->obj_id;
72 if (t->chunk_id == 0 && t->extra_available) {
73 /* Store the extra header info instead */
74 /* We save the parent object in the chunk_id */
75 ptt->chunk_id = EXTRA_HEADER_INFO_FLAG | t->extra_parent_id;
76 if (t->extra_is_shrink)
77 ptt->chunk_id |= EXTRA_SHRINK_FLAG;
79 ptt->chunk_id |= EXTRA_SHADOWS_FLAG;
81 ptt->obj_id &= ~EXTRA_OBJECT_TYPE_MASK;
82 ptt->obj_id |= (t->extra_obj_type << EXTRA_OBJECT_TYPE_SHIFT);
84 if (t->extra_obj_type == YAFFS_OBJECT_TYPE_HARDLINK)
85 ptt->n_bytes = t->extra_equiv_id;
86 else if (t->extra_obj_type == YAFFS_OBJECT_TYPE_FILE)
87 ptt->n_bytes = t->extra_length;
92 yaffs_dump_packed_tags2_tags_only(ptt);
96 void yaffs_pack_tags2(struct yaffs_packed_tags2 *pt,
97 const struct yaffs_ext_tags *t, int tags_ecc)
99 yaffs_pack_tags2_tags_only(&pt->t, t);
102 yaffs_ecc_calc_other((unsigned char *)&pt->t,
104 yaffs_packed_tags2_tags_only),
108 void yaffs_unpack_tags2_tags_only(struct yaffs_ext_tags *t,
109 struct yaffs_packed_tags2_tags_only *ptt)
112 memset(t, 0, sizeof(struct yaffs_ext_tags));
116 if (ptt->seq_number != 0xFFFFFFFF) {
119 t->obj_id = ptt->obj_id;
120 t->chunk_id = ptt->chunk_id;
121 t->n_bytes = ptt->n_bytes;
123 t->serial_number = 0;
124 t->seq_number = ptt->seq_number;
126 /* Do extra header info stuff */
128 if (ptt->chunk_id & EXTRA_HEADER_INFO_FLAG) {
132 t->extra_available = 1;
134 ptt->chunk_id & (~(ALL_EXTRA_FLAGS));
136 (ptt->chunk_id & EXTRA_SHRINK_FLAG) ? 1 : 0;
138 (ptt->chunk_id & EXTRA_SHADOWS_FLAG) ? 1 : 0;
140 ptt->obj_id >> EXTRA_OBJECT_TYPE_SHIFT;
141 t->obj_id &= ~EXTRA_OBJECT_TYPE_MASK;
143 if (t->extra_obj_type == YAFFS_OBJECT_TYPE_HARDLINK)
144 t->extra_equiv_id = ptt->n_bytes;
146 t->extra_length = ptt->n_bytes;
150 yaffs_dump_packed_tags2_tags_only(ptt);
155 void yaffs_unpack_tags2(struct yaffs_ext_tags *t, struct yaffs_packed_tags2 *pt,
159 enum yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
161 if (pt->t.seq_number != 0xFFFFFFFF && tags_ecc) {
162 /* Chunk is in use and we need to do ECC */
164 struct yaffs_ecc_other ecc;
166 yaffs_ecc_calc_other((unsigned char *)&pt->t,
168 yaffs_packed_tags2_tags_only),
171 yaffs_ecc_correct_other((unsigned char *)&pt->t,
173 yaffs_packed_tags2_tags_only),
177 ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
180 ecc_result = YAFFS_ECC_RESULT_FIXED;
183 ecc_result = YAFFS_ECC_RESULT_UNFIXED;
186 ecc_result = YAFFS_ECC_RESULT_UNKNOWN;
190 yaffs_unpack_tags2_tags_only(t, &pt->t);
192 t->ecc_result = ecc_result;
194 yaffs_dump_packed_tags2(pt);