xref: /openbmc/linux/fs/xfs/libxfs/xfs_ialloc.h (revision b732539e)
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_H__
19 #define	__XFS_IALLOC_H__
20 
21 struct xfs_buf;
22 struct xfs_dinode;
23 struct xfs_imap;
24 struct xfs_mount;
25 struct xfs_trans;
26 struct xfs_btree_cur;
27 
28 /* Move inodes in clusters of this size */
29 #define	XFS_INODE_BIG_CLUSTER_SIZE	8192
30 
31 struct xfs_icluster {
32 	bool		deleted;	/* record is deleted */
33 	xfs_ino_t	first_ino;	/* first inode number */
34 	uint64_t	alloc;		/* inode phys. allocation bitmap for
35 					 * sparse chunks */
36 };
37 
38 /* Calculate and return the number of filesystem blocks per inode cluster */
39 static inline int
40 xfs_icluster_size_fsb(
41 	struct xfs_mount	*mp)
42 {
43 	if (mp->m_sb.sb_blocksize >= mp->m_inode_cluster_size)
44 		return 1;
45 	return mp->m_inode_cluster_size >> mp->m_sb.sb_blocklog;
46 }
47 
48 /*
49  * Make an inode pointer out of the buffer/offset.
50  */
51 static inline struct xfs_dinode *
52 xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o)
53 {
54 	return xfs_buf_offset(b, o << (mp)->m_sb.sb_inodelog);
55 }
56 
57 /*
58  * Allocate an inode on disk.
59  * Mode is used to tell whether the new inode will need space, and whether
60  * it is a directory.
61  *
62  * To work within the constraint of one allocation per transaction,
63  * xfs_dialloc() is designed to be called twice if it has to do an
64  * allocation to make more free inodes.  If an inode is
65  * available without an allocation, agbp would be set to the current
66  * agbp and alloc_done set to false.
67  * If an allocation needed to be done, agbp would be set to the
68  * inode header of the allocation group and alloc_done set to true.
69  * The caller should then commit the current transaction and allocate a new
70  * transaction.  xfs_dialloc() should then be called again with
71  * the agbp value returned from the previous call.
72  *
73  * Once we successfully pick an inode its number is returned and the
74  * on-disk data structures are updated.  The inode itself is not read
75  * in, since doing so would break ordering constraints with xfs_reclaim.
76  *
77  * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
78  */
79 int					/* error */
80 xfs_dialloc(
81 	struct xfs_trans *tp,		/* transaction pointer */
82 	xfs_ino_t	parent,		/* parent inode (directory) */
83 	umode_t		mode,		/* mode bits for new inode */
84 	struct xfs_buf	**agbp,		/* buf for a.g. inode header */
85 	xfs_ino_t	*inop);		/* inode number allocated */
86 
87 /*
88  * Free disk inode.  Carefully avoids touching the incore inode, all
89  * manipulations incore are the caller's responsibility.
90  * The on-disk inode is not changed by this operation, only the
91  * btree (free inode mask) is changed.
92  */
93 int					/* error */
94 xfs_difree(
95 	struct xfs_trans *tp,		/* transaction pointer */
96 	xfs_ino_t	inode,		/* inode to be freed */
97 	struct xfs_defer_ops *dfops,	/* extents to free */
98 	struct xfs_icluster *ifree);	/* cluster info if deleted */
99 
100 /*
101  * Return the location of the inode in imap, for mapping it into a buffer.
102  */
103 int
104 xfs_imap(
105 	struct xfs_mount *mp,		/* file system mount structure */
106 	struct xfs_trans *tp,		/* transaction pointer */
107 	xfs_ino_t	ino,		/* inode to locate */
108 	struct xfs_imap	*imap,		/* location map structure */
109 	uint		flags);		/* flags for inode btree lookup */
110 
111 /*
112  * Compute and fill in value of m_in_maxlevels.
113  */
114 void
115 xfs_ialloc_compute_maxlevels(
116 	struct xfs_mount *mp);		/* file system mount structure */
117 
118 /*
119  * Log specified fields for the ag hdr (inode section)
120  */
121 void
122 xfs_ialloc_log_agi(
123 	struct xfs_trans *tp,		/* transaction pointer */
124 	struct xfs_buf	*bp,		/* allocation group header buffer */
125 	int		fields);	/* bitmask of fields to log */
126 
127 /*
128  * Read in the allocation group header (inode allocation section)
129  */
130 int					/* error */
131 xfs_ialloc_read_agi(
132 	struct xfs_mount *mp,		/* file system mount structure */
133 	struct xfs_trans *tp,		/* transaction pointer */
134 	xfs_agnumber_t	agno,		/* allocation group number */
135 	struct xfs_buf	**bpp);		/* allocation group hdr buf */
136 
137 /*
138  * Read in the allocation group header to initialise the per-ag data
139  * in the mount structure
140  */
141 int
142 xfs_ialloc_pagi_init(
143 	struct xfs_mount *mp,		/* file system mount structure */
144 	struct xfs_trans *tp,		/* transaction pointer */
145         xfs_agnumber_t  agno);		/* allocation group number */
146 
147 /*
148  * Lookup a record by ino in the btree given by cur.
149  */
150 int xfs_inobt_lookup(struct xfs_btree_cur *cur, xfs_agino_t ino,
151 		xfs_lookup_t dir, int *stat);
152 
153 /*
154  * Get the data from the pointed-to record.
155  */
156 int xfs_inobt_get_rec(struct xfs_btree_cur *cur,
157 		xfs_inobt_rec_incore_t *rec, int *stat);
158 
159 /*
160  * Inode chunk initialisation routine
161  */
162 int xfs_ialloc_inode_init(struct xfs_mount *mp, struct xfs_trans *tp,
163 			  struct list_head *buffer_list, int icount,
164 			  xfs_agnumber_t agno, xfs_agblock_t agbno,
165 			  xfs_agblock_t length, unsigned int gen);
166 
167 int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp,
168 		xfs_agnumber_t agno, struct xfs_buf **bpp);
169 
170 union xfs_btree_rec;
171 void xfs_inobt_btrec_to_irec(struct xfs_mount *mp, union xfs_btree_rec *rec,
172 		struct xfs_inobt_rec_incore *irec);
173 int xfs_ialloc_has_inodes_at_extent(struct xfs_btree_cur *cur,
174 		xfs_agblock_t bno, xfs_extlen_t len, bool *exists);
175 int xfs_ialloc_has_inode_record(struct xfs_btree_cur *cur, xfs_agino_t low,
176 		xfs_agino_t high, bool *exists);
177 int xfs_ialloc_count_inodes(struct xfs_btree_cur *cur, xfs_agino_t *count,
178 		xfs_agino_t *freecount);
179 
180 int xfs_ialloc_cluster_alignment(struct xfs_mount *mp);
181 void xfs_ialloc_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
182 		xfs_agino_t *first, xfs_agino_t *last);
183 bool xfs_verify_agino(struct xfs_mount *mp, xfs_agnumber_t agno,
184 		xfs_agino_t agino);
185 bool xfs_verify_ino(struct xfs_mount *mp, xfs_ino_t ino);
186 bool xfs_internal_inum(struct xfs_mount *mp, xfs_ino_t ino);
187 bool xfs_verify_dir_ino(struct xfs_mount *mp, xfs_ino_t ino);
188 
189 #endif	/* __XFS_IALLOC_H__ */
190