xref: /linux/fs/xfs/libxfs/xfs_shared.h (revision 1f2367a39f17bd553a75e179a747f9b257bc9478)
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_agi_buf_ops;
26 extern const struct xfs_buf_ops xfs_agf_buf_ops;
27 extern const struct xfs_buf_ops xfs_agfl_buf_ops;
28 extern const struct xfs_buf_ops xfs_bnobt_buf_ops;
29 extern const struct xfs_buf_ops xfs_cntbt_buf_ops;
30 extern const struct xfs_buf_ops xfs_rmapbt_buf_ops;
31 extern const struct xfs_buf_ops xfs_refcountbt_buf_ops;
32 extern const struct xfs_buf_ops xfs_attr3_leaf_buf_ops;
33 extern const struct xfs_buf_ops xfs_attr3_rmt_buf_ops;
34 extern const struct xfs_buf_ops xfs_bmbt_buf_ops;
35 extern const struct xfs_buf_ops xfs_da3_node_buf_ops;
36 extern const struct xfs_buf_ops xfs_dquot_buf_ops;
37 extern const struct xfs_buf_ops xfs_symlink_buf_ops;
38 extern const struct xfs_buf_ops xfs_agi_buf_ops;
39 extern const struct xfs_buf_ops xfs_inobt_buf_ops;
40 extern const struct xfs_buf_ops xfs_finobt_buf_ops;
41 extern const struct xfs_buf_ops xfs_inode_buf_ops;
42 extern const struct xfs_buf_ops xfs_inode_buf_ra_ops;
43 extern const struct xfs_buf_ops xfs_dquot_buf_ops;
44 extern const struct xfs_buf_ops xfs_dquot_buf_ra_ops;
45 extern const struct xfs_buf_ops xfs_sb_buf_ops;
46 extern const struct xfs_buf_ops xfs_sb_quiet_buf_ops;
47 extern const struct xfs_buf_ops xfs_symlink_buf_ops;
48 extern const struct xfs_buf_ops xfs_rtbuf_ops;
49 
50 /* log size calculation functions */
51 int	xfs_log_calc_unit_res(struct xfs_mount *mp, int unit_bytes);
52 int	xfs_log_calc_minimum_size(struct xfs_mount *);
53 
54 struct xfs_trans_res;
55 void	xfs_log_get_max_trans_res(struct xfs_mount *mp,
56 				  struct xfs_trans_res *max_resp);
57 
58 /*
59  * Values for t_flags.
60  */
61 #define	XFS_TRANS_DIRTY		0x01	/* something needs to be logged */
62 #define	XFS_TRANS_SB_DIRTY	0x02	/* superblock is modified */
63 #define	XFS_TRANS_PERM_LOG_RES	0x04	/* xact took a permanent log res */
64 #define	XFS_TRANS_SYNC		0x08	/* make commit synchronous */
65 #define XFS_TRANS_DQ_DIRTY	0x10	/* at least one dquot in trx dirty */
66 #define XFS_TRANS_RESERVE	0x20    /* OK to use reserved data blocks */
67 #define XFS_TRANS_NO_WRITECOUNT 0x40	/* do not elevate SB writecount */
68 #define XFS_TRANS_NOFS		0x80	/* pass KM_NOFS to kmem_alloc */
69 /*
70  * LOWMODE is used by the allocator to activate the lowspace algorithm - when
71  * free space is running low the extent allocator may choose to allocate an
72  * extent from an AG without leaving sufficient space for a btree split when
73  * inserting the new extent. In this case the allocator will enable the
74  * lowspace algorithm which is supposed to allow further allocations (such as
75  * btree splits and newroots) to allocate from sequential AGs. In order to
76  * avoid locking AGs out of order the lowspace algorithm will start searching
77  * for free space from AG 0. If the correct transaction reservations have been
78  * made then this algorithm will eventually find all the space it needs.
79  */
80 #define XFS_TRANS_LOWMODE	0x100	/* allocate in low space mode */
81 
82 /*
83  * Field values for xfs_trans_mod_sb.
84  */
85 #define	XFS_TRANS_SB_ICOUNT		0x00000001
86 #define	XFS_TRANS_SB_IFREE		0x00000002
87 #define	XFS_TRANS_SB_FDBLOCKS		0x00000004
88 #define	XFS_TRANS_SB_RES_FDBLOCKS	0x00000008
89 #define	XFS_TRANS_SB_FREXTENTS		0x00000010
90 #define	XFS_TRANS_SB_RES_FREXTENTS	0x00000020
91 #define	XFS_TRANS_SB_DBLOCKS		0x00000040
92 #define	XFS_TRANS_SB_AGCOUNT		0x00000080
93 #define	XFS_TRANS_SB_IMAXPCT		0x00000100
94 #define	XFS_TRANS_SB_REXTSIZE		0x00000200
95 #define	XFS_TRANS_SB_RBMBLOCKS		0x00000400
96 #define	XFS_TRANS_SB_RBLOCKS		0x00000800
97 #define	XFS_TRANS_SB_REXTENTS		0x00001000
98 #define	XFS_TRANS_SB_REXTSLOG		0x00002000
99 
100 /*
101  * Here we centralize the specification of XFS meta-data buffer reference count
102  * values.  This determines how hard the buffer cache tries to hold onto the
103  * buffer.
104  */
105 #define	XFS_AGF_REF		4
106 #define	XFS_AGI_REF		4
107 #define	XFS_AGFL_REF		3
108 #define	XFS_INO_BTREE_REF	3
109 #define	XFS_ALLOC_BTREE_REF	2
110 #define	XFS_BMAP_BTREE_REF	2
111 #define	XFS_RMAP_BTREE_REF	2
112 #define	XFS_DIR_BTREE_REF	2
113 #define	XFS_INO_REF		2
114 #define	XFS_ATTR_BTREE_REF	1
115 #define	XFS_DQUOT_REF		1
116 #define	XFS_REFC_BTREE_REF	1
117 #define	XFS_SSB_REF		0
118 
119 /*
120  * Flags for xfs_trans_ichgtime().
121  */
122 #define	XFS_ICHGTIME_MOD	0x1	/* data fork modification timestamp */
123 #define	XFS_ICHGTIME_CHG	0x2	/* inode field change timestamp */
124 #define	XFS_ICHGTIME_CREATE	0x4	/* inode create timestamp */
125 
126 
127 /*
128  * Symlink decoding/encoding functions
129  */
130 int xfs_symlink_blocks(struct xfs_mount *mp, int pathlen);
131 int xfs_symlink_hdr_set(struct xfs_mount *mp, xfs_ino_t ino, uint32_t offset,
132 			uint32_t size, struct xfs_buf *bp);
133 bool xfs_symlink_hdr_ok(xfs_ino_t ino, uint32_t offset,
134 			uint32_t size, struct xfs_buf *bp);
135 void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp,
136 				 struct xfs_inode *ip, struct xfs_ifork *ifp);
137 xfs_failaddr_t xfs_symlink_shortform_verify(struct xfs_inode *ip);
138 
139 #endif /* __XFS_SHARED_H__ */
140