xref: /linux/fs/xfs/libxfs/xfs_shared.h (revision b8e85e6f3a09fc56b0ff574887798962ef8a8f80)
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 /* Transaction needs to be logged */
58 #define XFS_TRANS_DIRTY			(1u << 0)
59 /* Superblock is dirty and needs to be logged */
60 #define XFS_TRANS_SB_DIRTY		(1u << 1)
61 /* Transaction took a permanent log reservation */
62 #define XFS_TRANS_PERM_LOG_RES		(1u << 2)
63 /* Synchronous transaction commit needed */
64 #define XFS_TRANS_SYNC			(1u << 3)
65 /* Transaction can use reserve block pool */
66 #define XFS_TRANS_RESERVE		(1u << 4)
67 /* Transaction should avoid VFS level superblock write accounting */
68 #define XFS_TRANS_NO_WRITECOUNT		(1u << 5)
69 /* Transaction has freed blocks returned to it's reservation */
70 #define XFS_TRANS_RES_FDBLKS		(1u << 6)
71 /* Transaction contains an intent done log item */
72 #define XFS_TRANS_HAS_INTENT_DONE	(1u << 7)
73 
74 /*
75  * LOWMODE is used by the allocator to activate the lowspace algorithm - when
76  * free space is running low the extent allocator may choose to allocate an
77  * extent from an AG without leaving sufficient space for a btree split when
78  * inserting the new extent. In this case the allocator will enable the
79  * lowspace algorithm which is supposed to allow further allocations (such as
80  * btree splits and newroots) to allocate from sequential AGs. In order to
81  * avoid locking AGs out of order the lowspace algorithm will start searching
82  * for free space from AG 0. If the correct transaction reservations have been
83  * made then this algorithm will eventually find all the space it needs.
84  */
85 #define XFS_TRANS_LOWMODE	0x100	/* allocate in low space mode */
86 
87 /*
88  * Field values for xfs_trans_mod_sb.
89  */
90 #define	XFS_TRANS_SB_ICOUNT		0x00000001
91 #define	XFS_TRANS_SB_IFREE		0x00000002
92 #define	XFS_TRANS_SB_FDBLOCKS		0x00000004
93 #define	XFS_TRANS_SB_RES_FDBLOCKS	0x00000008
94 #define	XFS_TRANS_SB_FREXTENTS		0x00000010
95 #define	XFS_TRANS_SB_RES_FREXTENTS	0x00000020
96 #define	XFS_TRANS_SB_DBLOCKS		0x00000040
97 #define	XFS_TRANS_SB_AGCOUNT		0x00000080
98 #define	XFS_TRANS_SB_IMAXPCT		0x00000100
99 #define	XFS_TRANS_SB_REXTSIZE		0x00000200
100 #define	XFS_TRANS_SB_RBMBLOCKS		0x00000400
101 #define	XFS_TRANS_SB_RBLOCKS		0x00000800
102 #define	XFS_TRANS_SB_REXTENTS		0x00001000
103 #define	XFS_TRANS_SB_REXTSLOG		0x00002000
104 
105 /*
106  * Here we centralize the specification of XFS meta-data buffer reference count
107  * values.  This determines how hard the buffer cache tries to hold onto the
108  * buffer.
109  */
110 #define	XFS_AGF_REF		4
111 #define	XFS_AGI_REF		4
112 #define	XFS_AGFL_REF		3
113 #define	XFS_INO_BTREE_REF	3
114 #define	XFS_ALLOC_BTREE_REF	2
115 #define	XFS_BMAP_BTREE_REF	2
116 #define	XFS_RMAP_BTREE_REF	2
117 #define	XFS_DIR_BTREE_REF	2
118 #define	XFS_INO_REF		2
119 #define	XFS_ATTR_BTREE_REF	1
120 #define	XFS_DQUOT_REF		1
121 #define	XFS_REFC_BTREE_REF	1
122 #define	XFS_SSB_REF		0
123 
124 /*
125  * Flags for xfs_trans_ichgtime().
126  */
127 #define	XFS_ICHGTIME_MOD	0x1	/* data fork modification timestamp */
128 #define	XFS_ICHGTIME_CHG	0x2	/* inode field change timestamp */
129 #define	XFS_ICHGTIME_CREATE	0x4	/* inode create timestamp */
130 
131 
132 /*
133  * Symlink decoding/encoding functions
134  */
135 int xfs_symlink_blocks(struct xfs_mount *mp, int pathlen);
136 int xfs_symlink_hdr_set(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset,
137 			uint32_t size, struct xfs_buf *bp);
138 bool xfs_symlink_hdr_ok(xfs_ino_t ino, uint32_t offset,
139 			uint32_t size, struct xfs_buf *bp);
140 void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp,
141 				 struct xfs_inode *ip, struct xfs_ifork *ifp);
142 xfs_failaddr_t xfs_symlink_shortform_verify(void *sfp, int64_t size);
143 
144 /* Computed inode geometry for the filesystem. */
145 struct xfs_ino_geometry {
146 	/* Maximum inode count in this filesystem. */
147 	uint64_t	maxicount;
148 
149 	/* Actual inode cluster buffer size, in bytes. */
150 	unsigned int	inode_cluster_size;
151 
152 	/*
153 	 * Desired inode cluster buffer size, in bytes.  This value is not
154 	 * rounded up to at least one filesystem block, which is necessary for
155 	 * the sole purpose of validating sb_spino_align.  Runtime code must
156 	 * only ever use inode_cluster_size.
157 	 */
158 	unsigned int	inode_cluster_size_raw;
159 
160 	/* Inode cluster sizes, adjusted to be at least 1 fsb. */
161 	unsigned int	inodes_per_cluster;
162 	unsigned int	blocks_per_cluster;
163 
164 	/* Inode cluster alignment. */
165 	unsigned int	cluster_align;
166 	unsigned int	cluster_align_inodes;
167 	unsigned int	inoalign_mask;	/* mask sb_inoalignmt if used */
168 
169 	unsigned int	inobt_mxr[2]; /* max inobt btree records */
170 	unsigned int	inobt_mnr[2]; /* min inobt btree records */
171 	unsigned int	inobt_maxlevels; /* max inobt btree levels. */
172 
173 	/* Size of inode allocations under normal operation. */
174 	unsigned int	ialloc_inos;
175 	unsigned int	ialloc_blks;
176 
177 	/* Minimum inode blocks for a sparse allocation. */
178 	unsigned int	ialloc_min_blks;
179 
180 	/* stripe unit inode alignment */
181 	unsigned int	ialloc_align;
182 
183 	unsigned int	agino_log;	/* #bits for agino in inum */
184 
185 	/* precomputed default inode attribute fork offset */
186 	unsigned int	attr_fork_offset;
187 
188 	/* precomputed value for di_flags2 */
189 	uint64_t	new_diflags2;
190 
191 };
192 
193 #endif /* __XFS_SHARED_H__ */
194