root/fs/jffs2/summary.h

INCLUDED FROM

   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 
  40 struct jffs2_sum_unknown_flash
  41 {
  42         jint16_t nodetype;      /* node type */
  43 };
  44 
  45 struct 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 
  54 struct 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 
  67 struct 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 
  76 struct jffs2_sum_xref_flash
  77 {
  78         jint16_t nodetype;      /* == JFFS2_NODETYPE_XREF */
  79         jint32_t offset;        /* offset on jeb */
  80 } __attribute__((packed));
  81 
  82 union 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 
  93 struct jffs2_sum_unknown_mem
  94 {
  95         union jffs2_sum_mem *next;
  96         jint16_t nodetype;      /* node type */
  97 };
  98 
  99 struct 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 
 109 struct 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 
 123 struct 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 
 133 struct jffs2_sum_xref_mem
 134 {
 135         union jffs2_sum_mem *next;
 136         jint16_t nodetype;
 137         jint32_t offset;
 138 } __attribute__((packed));
 139 
 140 union 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 
 151 struct 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 
 164 struct 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)
 175 int jffs2_sum_init(struct jffs2_sb_info *c);
 176 void jffs2_sum_exit(struct jffs2_sb_info *c);
 177 void jffs2_sum_disable_collecting(struct jffs2_summary *s);
 178 int jffs2_sum_is_disabled(struct jffs2_summary *s);
 179 void jffs2_sum_reset_collected(struct jffs2_summary *s);
 180 void jffs2_sum_move_collected(struct jffs2_sb_info *c, struct jffs2_summary *s);
 181 int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
 182                         unsigned long count,  uint32_t to);
 183 int jffs2_sum_write_sumnode(struct jffs2_sb_info *c);
 184 int jffs2_sum_add_padding_mem(struct jffs2_summary *s, uint32_t size);
 185 int jffs2_sum_add_inode_mem(struct jffs2_summary *s, struct jffs2_raw_inode *ri, uint32_t ofs);
 186 int jffs2_sum_add_dirent_mem(struct jffs2_summary *s, struct jffs2_raw_dirent *rd, uint32_t ofs);
 187 int jffs2_sum_add_xattr_mem(struct jffs2_summary *s, struct jffs2_raw_xattr *rx, uint32_t ofs);
 188 int jffs2_sum_add_xref_mem(struct jffs2_summary *s, struct jffs2_raw_xref *rr, uint32_t ofs);
 189 int 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 */