fs/jffs2/jffs2_nand_private.h

   1 #ifndef jffs2_private_h
   2 #define jffs2_private_h
   3
   4 #include <jffs2/jffs2.h>
   5
   6 struct b_node {
   7         struct b_node *next;
   8 };
   9
  10 struct b_inode {
  11         struct b_inode *next;
  12         u32 offset;     /* physical offset to beginning of real inode */
  13         u32 version;
  14         u32 ino;
  15         u32 isize;
  16         u32 csize;
  17 };
  18
  19 struct b_dirent {
  20         struct b_dirent *next;
  21         u32 offset;     /* physical offset to beginning of real dirent */
  22         u32 version;
  23         u32 pino;
  24         u32 ino;
  25         unsigned int nhash;
  26         unsigned char nsize;
  27         unsigned char type;
  28 };
  29
  30 struct b_list {
  31         struct b_node *listTail;
  32         struct b_node *listHead;
  33         unsigned int listCount;
  34         struct mem_block *listMemBase;
  35 };
  36
  37 struct b_lists {
  38         char *partOffset;
  39         struct b_list dir;
  40         struct b_list frag;
  41 };
  42
  43 struct b_compr_info {
  44         u32 num_frags;
  45         u32 compr_sum;
  46         u32 decompr_sum;
  47 };
  48
  49 struct b_jffs2_info {
  50         struct b_compr_info compr_info[JFFS2_NUM_COMPR];
  51 };
  52
  53 static inline int
  54 hdr_crc(struct jffs2_unknown_node *node)
  55 {
  56 #if 1
  57         u32 crc = crc32_no_comp(0, (unsigned char *)node, sizeof(struct jffs2_unknown_node) - 4);
  58 #else
  59         /* what's the semantics of this? why is this here? */
  60         u32 crc = crc32_no_comp(~0, (unsigned char *)node, sizeof(struct jffs2_unknown_node) - 4);
  61
  62         crc ^= ~0;
  63 #endif
  64         if (node->hdr_crc != crc) {
  65                 return 0;
  66         } else {
  67                 return 1;
  68         }
  69 }
  70
  71 static inline int
  72 dirent_crc(struct jffs2_raw_dirent *node)
  73 {
  74         if (node->node_crc != crc32_no_comp(0, (unsigned char *)node, sizeof(struct jffs2_raw_dirent) - 8)) {
  75                 return 0;
  76         } else {
  77                 return 1;
  78         }
  79 }
  80
  81 static inline int
  82 dirent_name_crc(struct jffs2_raw_dirent *node)
  83 {
  84         if (node->name_crc != crc32_no_comp(0, (unsigned char *)&(node->name), node->nsize)) {
  85                 return 0;
  86         } else {
  87                 return 1;
  88         }
  89 }
  90
  91 static inline int
  92 inode_crc(struct jffs2_raw_inode *node)
  93 {
  94         if (node->node_crc != crc32_no_comp(0, (unsigned char *)node, sizeof(struct jffs2_raw_inode) - 8)) {
  95                 return 0;
  96         } else {
  97                 return 1;
  98         }
  99 }
 100
 101 /* Borrowed from include/linux/dcache.h */
 102
 103 /* Name hashing routines. Initial hash value */
 104 /* Hash courtesy of the R5 hash in reiserfs modulo sign bits */
 105 #define init_name_hash()                0
 106
 107 /* partial hash update function. Assume roughly 4 bits per character */
 108 static inline unsigned long
 109 partial_name_hash(unsigned long c, unsigned long prevhash)
 110 {
 111         return (prevhash + (c << 4) + (c >> 4)) * 11;
 112 }
 113
 114 /*
 115  * Finally: cut down the number of bits to a int value (and try to avoid
 116  * losing bits)
 117  */
 118 static inline unsigned long end_name_hash(unsigned long hash)
 119 {
 120         return (unsigned int) hash;
 121 }
 122
 123 /* Compute the hash for a name string. */
 124 static inline unsigned int
 125 full_name_hash(const unsigned char *name, unsigned int len)
 126 {
 127         unsigned long hash = init_name_hash();
 128         while (len--)
 129                 hash = partial_name_hash(*name++, hash);
 130         return end_name_hash(hash);
 131 }
 132
 133 #endif /* jffs2_private.h */