xref: /openbmc/linux/fs/xfs/libxfs/xfs_shared.h (revision 8dda2eac)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4  * Copyright (c) 2013 Red Hat, Inc.
5  * All Rights Reserved.
6  */
7 #ifndef __XFS_SHARED_H__
8 #define __XFS_SHARED_H__
9 
10 /*
11  * Definitions shared between kernel and userspace that don't fit into any other
12  * header file that is shared with userspace.
13  */
14 struct xfs_ifork;
15 struct xfs_buf;
16 struct xfs_buf_ops;
17 struct xfs_mount;
18 struct xfs_trans;
19 struct xfs_inode;
20 
21 /*
22  * Buffer verifier operations are widely used, including userspace tools
23  */
24 extern const struct xfs_buf_ops xfs_agf_buf_ops;
25 extern const struct xfs_buf_ops xfs_agfl_buf_ops;
26 extern const struct xfs_buf_ops xfs_agi_buf_ops;
27 extern const struct xfs_buf_ops xfs_attr3_leaf_buf_ops;
28 extern const struct xfs_buf_ops xfs_attr3_rmt_buf_ops;
29 extern const struct xfs_buf_ops xfs_bmbt_buf_ops;
30 extern const struct xfs_buf_ops xfs_bnobt_buf_ops;
31 extern const struct xfs_buf_ops xfs_cntbt_buf_ops;
32 extern const struct xfs_buf_ops xfs_da3_node_buf_ops;
33 extern const struct xfs_buf_ops xfs_dquot_buf_ops;
34 extern const struct xfs_buf_ops xfs_dquot_buf_ra_ops;
35 extern const struct xfs_buf_ops xfs_finobt_buf_ops;
36 extern const struct xfs_buf_ops xfs_inobt_buf_ops;
37 extern const struct xfs_buf_ops xfs_inode_buf_ops;
38 extern const struct xfs_buf_ops xfs_inode_buf_ra_ops;
39 extern const struct xfs_buf_ops xfs_refcountbt_buf_ops;
40 extern const struct xfs_buf_ops xfs_rmapbt_buf_ops;
41 extern const struct xfs_buf_ops xfs_rtbuf_ops;
42 extern const struct xfs_buf_ops xfs_sb_buf_ops;
43 extern const struct xfs_buf_ops xfs_sb_quiet_buf_ops;
44 extern const struct xfs_buf_ops xfs_symlink_buf_ops;
45 
46 /* log size calculation functions */
47 int	xfs_log_calc_unit_res(struct xfs_mount *mp, int unit_bytes);
48 int	xfs_log_calc_minimum_size(struct xfs_mount *);
49 
50 struct xfs_trans_res;
51 void	xfs_log_get_max_trans_res(struct xfs_mount *mp,
52 				  struct xfs_trans_res *max_resp);
53 
54 /*
55  * Values for t_flags.
56  */
57 #define	XFS_TRANS_DIRTY		0x01	/* something needs to be logged */
58 #define	XFS_TRANS_SB_DIRTY	0x02	/* superblock is modified */
59 #define	XFS_TRANS_PERM_LOG_RES	0x04	/* xact took a permanent log res */
60 #define	XFS_TRANS_SYNC		0x08	/* make commit synchronous */
61 #define XFS_TRANS_RESERVE	0x20    /* OK to use reserved data blocks */
62 #define XFS_TRANS_NO_WRITECOUNT 0x40	/* do not elevate SB writecount */
63 #define XFS_TRANS_RES_FDBLKS	0x80	/* reserve newly freed blocks */
64 /*
65  * LOWMODE is used by the allocator to activate the lowspace algorithm - when
66  * free space is running low the extent allocator may choose to allocate an
67  * extent from an AG without leaving sufficient space for a btree split when
68  * inserting the new extent. In this case the allocator will enable the
69  * lowspace algorithm which is supposed to allow further allocations (such as
70  * btree splits and newroots) to allocate from sequential AGs. In order to
71  * avoid locking AGs out of order the lowspace algorithm will start searching
72  * for free space from AG 0. If the correct transaction reservations have been
73  * made then this algorithm will eventually find all the space it needs.
74  */
75 #define XFS_TRANS_LOWMODE	0x100	/* allocate in low space mode */
76 
77 /*
78  * Field values for xfs_trans_mod_sb.
79  */
80 #define	XFS_TRANS_SB_ICOUNT		0x00000001
81 #define	XFS_TRANS_SB_IFREE		0x00000002
82 #define	XFS_TRANS_SB_FDBLOCKS		0x00000004
83 #define	XFS_TRANS_SB_RES_FDBLOCKS	0x00000008
84 #define	XFS_TRANS_SB_FREXTENTS		0x00000010
85 #define	XFS_TRANS_SB_RES_FREXTENTS	0x00000020
86 #define	XFS_TRANS_SB_DBLOCKS		0x00000040
87 #define	XFS_TRANS_SB_AGCOUNT		0x00000080
88 #define	XFS_TRANS_SB_IMAXPCT		0x00000100
89 #define	XFS_TRANS_SB_REXTSIZE		0x00000200
90 #define	XFS_TRANS_SB_RBMBLOCKS		0x00000400
91 #define	XFS_TRANS_SB_RBLOCKS		0x00000800
92 #define	XFS_TRANS_SB_REXTENTS		0x00001000
93 #define	XFS_TRANS_SB_REXTSLOG		0x00002000
94 
95 /*
96  * Here we centralize the specification of XFS meta-data buffer reference count
97  * values.  This determines how hard the buffer cache tries to hold onto the
98  * buffer.
99  */
100 #define	XFS_AGF_REF		4
101 #define	XFS_AGI_REF		4
102 #define	XFS_AGFL_REF		3
103 #define	XFS_INO_BTREE_REF	3
104 #define	XFS_ALLOC_BTREE_REF	2
105 #define	XFS_BMAP_BTREE_REF	2
106 #define	XFS_RMAP_BTREE_REF	2
107 #define	XFS_DIR_BTREE_REF	2
108 #define	XFS_INO_REF		2
109 #define	XFS_ATTR_BTREE_REF	1
110 #define	XFS_DQUOT_REF		1
111 #define	XFS_REFC_BTREE_REF	1
112 #define	XFS_SSB_REF		0
113 
114 /*
115  * Flags for xfs_trans_ichgtime().
116  */
117 #define	XFS_ICHGTIME_MOD	0x1	/* data fork modification timestamp */
118 #define	XFS_ICHGTIME_CHG	0x2	/* inode field change timestamp */
119 #define	XFS_ICHGTIME_CREATE	0x4	/* inode create timestamp */
120 
121 
122 /*
123  * Symlink decoding/encoding functions
124  */
125 int xfs_symlink_blocks(struct xfs_mount *mp, int pathlen);
126 int xfs_symlink_hdr_set(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset,
127 			uint32_t size, struct xfs_buf *bp);
128 bool xfs_symlink_hdr_ok(xfs_ino_t ino, uint32_t offset,
129 			uint32_t size, struct xfs_buf *bp);
130 void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp,
131 				 struct xfs_inode *ip, struct xfs_ifork *ifp);
132 xfs_failaddr_t xfs_symlink_shortform_verify(struct xfs_inode *ip);
133 
134 /* Computed inode geometry for the filesystem. */
135 struct xfs_ino_geometry {
136 	/* Maximum inode count in this filesystem. */
137 	uint64_t	maxicount;
138 
139 	/* Actual inode cluster buffer size, in bytes. */
140 	unsigned int	inode_cluster_size;
141 
142 	/*
143 	 * Desired inode cluster buffer size, in bytes.  This value is not
144 	 * rounded up to at least one filesystem block, which is necessary for
145 	 * the sole purpose of validating sb_spino_align.  Runtime code must
146 	 * only ever use inode_cluster_size.
147 	 */
148 	unsigned int	inode_cluster_size_raw;
149 
150 	/* Inode cluster sizes, adjusted to be at least 1 fsb. */
151 	unsigned int	inodes_per_cluster;
152 	unsigned int	blocks_per_cluster;
153 
154 	/* Inode cluster alignment. */
155 	unsigned int	cluster_align;
156 	unsigned int	cluster_align_inodes;
157 	unsigned int	inoalign_mask;	/* mask sb_inoalignmt if used */
158 
159 	unsigned int	inobt_mxr[2]; /* max inobt btree records */
160 	unsigned int	inobt_mnr[2]; /* min inobt btree records */
161 	unsigned int	inobt_maxlevels; /* max inobt btree levels. */
162 
163 	/* Size of inode allocations under normal operation. */
164 	unsigned int	ialloc_inos;
165 	unsigned int	ialloc_blks;
166 
167 	/* Minimum inode blocks for a sparse allocation. */
168 	unsigned int	ialloc_min_blks;
169 
170 	/* stripe unit inode alignment */
171 	unsigned int	ialloc_align;
172 
173 	unsigned int	agino_log;	/* #bits for agino in inum */
174 
175 	/* precomputed default inode attribute fork offset */
176 	unsigned int	attr_fork_offset;
177 
178 	/* precomputed value for di_flags2 */
179 	uint64_t	new_diflags2;
180 
181 };
182 
183 #endif /* __XFS_SHARED_H__ */
184