1/*
2 * Copyright (c) 2000,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17 */
18#ifndef __XFS_IALLOC_BTREE_H__
19#define	__XFS_IALLOC_BTREE_H__
20
21/*
22 * Inode map on-disk structures
23 */
24
25struct xfs_buf;
26struct xfs_btree_cur;
27struct xfs_mount;
28
29/*
30 * There is a btree for the inode map per allocation group.
31 */
32#define	XFS_IBT_MAGIC	0x49414254	/* 'IABT' */
33
34typedef	__uint64_t	xfs_inofree_t;
35#define	XFS_INODES_PER_CHUNK		(NBBY * sizeof(xfs_inofree_t))
36#define	XFS_INODES_PER_CHUNK_LOG	(XFS_NBBYLOG + 3)
37#define	XFS_INOBT_ALL_FREE		((xfs_inofree_t)-1)
38#define	XFS_INOBT_MASK(i)		((xfs_inofree_t)1 << (i))
39
40static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
41{
42	return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
43}
44
45/*
46 * Data record structure
47 */
48typedef struct xfs_inobt_rec {
49	__be32		ir_startino;	/* starting inode number */
50	__be32		ir_freecount;	/* count of free inodes (set bits) */
51	__be64		ir_free;	/* free inode mask */
52} xfs_inobt_rec_t;
53
54typedef struct xfs_inobt_rec_incore {
55	xfs_agino_t	ir_startino;	/* starting inode number */
56	__int32_t	ir_freecount;	/* count of free inodes (set bits) */
57	xfs_inofree_t	ir_free;	/* free inode mask */
58} xfs_inobt_rec_incore_t;
59
60
61/*
62 * Key structure
63 */
64typedef struct xfs_inobt_key {
65	__be32		ir_startino;	/* starting inode number */
66} xfs_inobt_key_t;
67
68/* btree pointer type */
69typedef __be32 xfs_inobt_ptr_t;
70
71/*
72 * block numbers in the AG.
73 */
74#define	XFS_IBT_BLOCK(mp)		((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
75#define	XFS_PREALLOC_BLOCKS(mp)		((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
76
77/*
78 * Btree block header size depends on a superblock flag.
79 *
80 * (not quite yet, but soon)
81 */
82#define XFS_INOBT_BLOCK_LEN(mp)	XFS_BTREE_SBLOCK_LEN
83
84/*
85 * Record, key, and pointer address macros for btree blocks.
86 *
87 * (note that some of these may appear unused, but they are used in userspace)
88 */
89#define XFS_INOBT_REC_ADDR(mp, block, index) \
90	((xfs_inobt_rec_t *) \
91		((char *)(block) + \
92		 XFS_INOBT_BLOCK_LEN(mp) + \
93		 (((index) - 1) * sizeof(xfs_inobt_rec_t))))
94
95#define XFS_INOBT_KEY_ADDR(mp, block, index) \
96	((xfs_inobt_key_t *) \
97		((char *)(block) + \
98		 XFS_INOBT_BLOCK_LEN(mp) + \
99		 ((index) - 1) * sizeof(xfs_inobt_key_t)))
100
101#define XFS_INOBT_PTR_ADDR(mp, block, index, maxrecs) \
102	((xfs_inobt_ptr_t *) \
103		((char *)(block) + \
104		 XFS_INOBT_BLOCK_LEN(mp) + \
105		 (maxrecs) * sizeof(xfs_inobt_key_t) + \
106		 ((index) - 1) * sizeof(xfs_inobt_ptr_t)))
107
108extern struct xfs_btree_cur *xfs_inobt_init_cursor(struct xfs_mount *,
109		struct xfs_trans *, struct xfs_buf *, xfs_agnumber_t);
110extern int xfs_inobt_maxrecs(struct xfs_mount *, int, int);
111
112#endif	/* __XFS_IALLOC_BTREE_H__ */
113