Root/fs/jffs2/summary.h

1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2004 Ferenc Havasi <havasi@inf.u-szeged.hu>,
5 * Zoltan Sogor <weth@inf.u-szeged.hu>,
6 * Patrik Kluba <pajko@halom.u-szeged.hu>,
7 * University of Szeged, Hungary
8 *
9 * For licensing information, see the file 'LICENCE' in this directory.
10 *
11 */
12
13#ifndef JFFS2_SUMMARY_H
14#define JFFS2_SUMMARY_H
15
16/* Limit summary size to 64KiB so that we can kmalloc it. If the summary
17   is larger than that, we have to just ditch it and avoid using summary
18   for the eraseblock in question... and it probably doesn't hurt us much
19   anyway. */
20#define MAX_SUMMARY_SIZE 65536
21
22#include <linux/uio.h>
23#include <linux/jffs2.h>
24
25#define BLK_STATE_ALLFF 0
26#define BLK_STATE_CLEAN 1
27#define BLK_STATE_PARTDIRTY 2
28#define BLK_STATE_CLEANMARKER 3
29#define BLK_STATE_ALLDIRTY 4
30#define BLK_STATE_BADBLOCK 5
31
32#define JFFS2_SUMMARY_NOSUM_SIZE 0xffffffff
33#define JFFS2_SUMMARY_INODE_SIZE (sizeof(struct jffs2_sum_inode_flash))
34#define JFFS2_SUMMARY_DIRENT_SIZE(x) (sizeof(struct jffs2_sum_dirent_flash) + (x))
35#define JFFS2_SUMMARY_XATTR_SIZE (sizeof(struct jffs2_sum_xattr_flash))
36#define JFFS2_SUMMARY_XREF_SIZE (sizeof(struct jffs2_sum_xref_flash))
37
38/* Summary structures used on flash */
39
40struct jffs2_sum_unknown_flash
41{
42    jint16_t nodetype; /* node type */
43};
44
45struct jffs2_sum_inode_flash
46{
47    jint16_t nodetype; /* node type */
48    jint32_t inode; /* inode number */
49    jint32_t version; /* inode version */
50    jint32_t offset; /* offset on jeb */
51    jint32_t totlen; /* record length */
52} __attribute__((packed));
53
54struct jffs2_sum_dirent_flash
55{
56    jint16_t nodetype; /* == JFFS_NODETYPE_DIRENT */
57    jint32_t totlen; /* record length */
58    jint32_t offset; /* offset on jeb */
59    jint32_t pino; /* parent inode */
60    jint32_t version; /* dirent version */
61    jint32_t ino; /* == zero for unlink */
62    uint8_t nsize; /* dirent name size */
63    uint8_t type; /* dirent type */
64    uint8_t name[0]; /* dirent name */
65} __attribute__((packed));
66
67struct jffs2_sum_xattr_flash
68{
69    jint16_t nodetype; /* == JFFS2_NODETYPE_XATR */
70    jint32_t xid; /* xattr identifier */
71    jint32_t version; /* version number */
72    jint32_t offset; /* offset on jeb */
73    jint32_t totlen; /* node length */
74} __attribute__((packed));
75
76struct jffs2_sum_xref_flash
77{
78    jint16_t nodetype; /* == JFFS2_NODETYPE_XREF */
79    jint32_t offset; /* offset on jeb */
80} __attribute__((packed));
81
82union jffs2_sum_flash
83{
84    struct jffs2_sum_unknown_flash u;
85    struct jffs2_sum_inode_flash i;
86    struct jffs2_sum_dirent_flash d;
87    struct jffs2_sum_xattr_flash x;
88    struct jffs2_sum_xref_flash r;
89};
90
91/* Summary structures used in the memory */
92
93struct jffs2_sum_unknown_mem
94{
95    union jffs2_sum_mem *next;
96    jint16_t nodetype; /* node type */
97};
98
99struct jffs2_sum_inode_mem
100{
101    union jffs2_sum_mem *next;
102    jint16_t nodetype; /* node type */
103    jint32_t inode; /* inode number */
104    jint32_t version; /* inode version */
105    jint32_t offset; /* offset on jeb */
106    jint32_t totlen; /* record length */
107} __attribute__((packed));
108
109struct jffs2_sum_dirent_mem
110{
111    union jffs2_sum_mem *next;
112    jint16_t nodetype; /* == JFFS_NODETYPE_DIRENT */
113    jint32_t totlen; /* record length */
114    jint32_t offset; /* ofset on jeb */
115    jint32_t pino; /* parent inode */
116    jint32_t version; /* dirent version */
117    jint32_t ino; /* == zero for unlink */
118    uint8_t nsize; /* dirent name size */
119    uint8_t type; /* dirent type */
120    uint8_t name[0]; /* dirent name */
121} __attribute__((packed));
122
123struct jffs2_sum_xattr_mem
124{
125    union jffs2_sum_mem *next;
126    jint16_t nodetype;
127    jint32_t xid;
128    jint32_t version;
129    jint32_t offset;
130    jint32_t totlen;
131} __attribute__((packed));
132
133struct jffs2_sum_xref_mem
134{
135    union jffs2_sum_mem *next;
136    jint16_t nodetype;
137    jint32_t offset;
138} __attribute__((packed));
139
140union jffs2_sum_mem
141{
142    struct jffs2_sum_unknown_mem u;
143    struct jffs2_sum_inode_mem i;
144    struct jffs2_sum_dirent_mem d;
145    struct jffs2_sum_xattr_mem x;
146    struct jffs2_sum_xref_mem r;
147};
148
149/* Summary related information stored in superblock */
150
151struct jffs2_summary
152{
153    uint32_t sum_size; /* collected summary information for nextblock */
154    uint32_t sum_num;
155    uint32_t sum_padded;
156    union jffs2_sum_mem *sum_list_head;
157    union jffs2_sum_mem *sum_list_tail;
158
159    jint32_t *sum_buf; /* buffer for writing out summary */
160};
161
162/* Summary marker is stored at the end of every sumarized erase block */
163
164struct jffs2_sum_marker
165{
166    jint32_t offset; /* offset of the summary node in the jeb */
167    jint32_t magic; /* == JFFS2_SUM_MAGIC */
168};
169
170#define JFFS2_SUMMARY_FRAME_SIZE (sizeof(struct jffs2_raw_summary) + sizeof(struct jffs2_sum_marker))
171
172#ifdef CONFIG_JFFS2_SUMMARY /* SUMMARY SUPPORT ENABLED */
173
174#define jffs2_sum_active() (1)
175int jffs2_sum_init(struct jffs2_sb_info *c);
176void jffs2_sum_exit(struct jffs2_sb_info *c);
177void jffs2_sum_disable_collecting(struct jffs2_summary *s);
178int jffs2_sum_is_disabled(struct jffs2_summary *s);
179void jffs2_sum_reset_collected(struct jffs2_summary *s);
180void jffs2_sum_move_collected(struct jffs2_sb_info *c, struct jffs2_summary *s);
181int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
182            unsigned long count, uint32_t to);
183int jffs2_sum_write_sumnode(struct jffs2_sb_info *c);
184int jffs2_sum_add_padding_mem(struct jffs2_summary *s, uint32_t size);
185int jffs2_sum_add_inode_mem(struct jffs2_summary *s, struct jffs2_raw_inode *ri, uint32_t ofs);
186int jffs2_sum_add_dirent_mem(struct jffs2_summary *s, struct jffs2_raw_dirent *rd, uint32_t ofs);
187int jffs2_sum_add_xattr_mem(struct jffs2_summary *s, struct jffs2_raw_xattr *rx, uint32_t ofs);
188int jffs2_sum_add_xref_mem(struct jffs2_summary *s, struct jffs2_raw_xref *rr, uint32_t ofs);
189int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
190               struct jffs2_raw_summary *summary, uint32_t sumlen,
191               uint32_t *pseudo_random);
192
193#else /* SUMMARY DISABLED */
194
195#define jffs2_sum_active() (0)
196#define jffs2_sum_init(a) (0)
197#define jffs2_sum_exit(a)
198#define jffs2_sum_disable_collecting(a)
199#define jffs2_sum_is_disabled(a) (0)
200#define jffs2_sum_reset_collected(a)
201#define jffs2_sum_add_kvec(a,b,c,d) (0)
202#define jffs2_sum_move_collected(a,b)
203#define jffs2_sum_write_sumnode(a) (0)
204#define jffs2_sum_add_padding_mem(a,b)
205#define jffs2_sum_add_inode_mem(a,b,c)
206#define jffs2_sum_add_dirent_mem(a,b,c)
207#define jffs2_sum_add_xattr_mem(a,b,c)
208#define jffs2_sum_add_xref_mem(a,b,c)
209#define jffs2_sum_scan_sumnode(a,b,c,d,e) (0)
210
211#endif /* CONFIG_JFFS2_SUMMARY */
212
213#endif /* JFFS2_SUMMARY_H */
214

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