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 */
134