xref: /minix/minix/lib/libvtreefs/inode.h (revision 129adfeb)
1 #ifndef _VTREEFS_INODE_H
2 #define _VTREEFS_INODE_H
3 
4 /*
5  * Callback data can be a pointer or a (cast) integer value.  For now, we
6  * instruct the state transfer framework that it should translate only
7  * recognized pointers.
8  */
9 typedef cbdata_t cixfer_cbdata_t;
10 
11 /*
12  * The inodes that are active, form a fully connected tree.  Each node except
13  * the root node has a parent and a tail queue of children, where each child
14  * inode points to the "next" and "previous" inode with a common parent.
15  *
16  * Each inode that has a parent (i.e. active and not the root), is part of a
17  * <parent,name> -> inode hashtable, and if it has an index into the parent,
18  * is part of a <parent,index> -> inode hashtable.
19  *
20  * Inodes that are not active, are either deleted or free.  A deleted inode is
21  * in use as long as it still has a nonzero reference count, even though it is
22  * no longer part of the tree.  Inodes that are free, are part of the list of
23  * unused inodes.
24  */
25 struct inode {
26 	/* Inode identity */
27 	unsigned int i_num;		/* index number into the inode array */
28 	/* Note that the actual inode number (of type ino_t) is (i_num + 1). */
29 
30 	/* Inode metadata */
31 	struct inode_stat i_stat;	/* POSIX attributes */
32 	char i_namebuf[PNAME_MAX + 1];	/* buffer for static (short) names */
33 	char *i_name;			/* name of the inode in the parent */
34 	unsigned int i_count;		/* reference count */
35 	index_t i_index;		/* index number in parent / NO_INDEX */
36 	int i_indexed;			/* number of indexed entries */
37 	cixfer_cbdata_t i_cbdata;	/* callback data */
38 	unsigned short i_flags;		/* I_DELETED or 0 */
39 
40 	/* Tree structure */
41 	struct inode *i_parent;		/* parent of the node */
42 	TAILQ_ENTRY(inode) i_siblings;	/* hash list for parent's children */
43 	TAILQ_HEAD(i_child, inode) i_children;	/* parent's children */
44 
45 	/* Hash/free structure */
46 	LIST_ENTRY(inode) i_hname;	/* hash list for name hash table */
47 	LIST_ENTRY(inode) i_hindex;	/* hash list for index hash table */
48 	TAILQ_ENTRY(inode) i_unused;	/* list of unused nodes */
49 };
50 
51 #define I_DELETED 	0x1	/* the inode is scheduled for deletion */
52 
53 #endif /* _VTREEFS_INODE_H */
54