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