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xfs_dinode.h
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1 /*
2  * Copyright (c) 2000,2002,2005 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_DINODE_H__
19 #define __XFS_DINODE_H__
20 
21 #define XFS_DINODE_MAGIC 0x494e /* 'IN' */
22 #define XFS_DINODE_GOOD_VERSION(v) (((v) == 1 || (v) == 2))
23 
24 typedef struct xfs_timestamp {
25  __be32 t_sec; /* timestamp seconds */
26  __be32 t_nsec; /* timestamp nanoseconds */
28 
29 /*
30  * On-disk inode structure.
31  *
32  * This is just the header or "dinode core", the inode is expanded to fill a
33  * variable size the leftover area split into a data and an attribute fork.
34  * The format of the data and attribute fork depends on the format of the
35  * inode as indicated by di_format and di_aformat. To access the data and
36  * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
37  * below.
38  *
39  * There is a very similar struct icdinode in xfs_inode which matches the
40  * layout of the first 96 bytes of this structure, but is kept in native
41  * format instead of big endian.
42  */
43 typedef struct xfs_dinode {
44  __be16 di_magic; /* inode magic # = XFS_DINODE_MAGIC */
45  __be16 di_mode; /* mode and type of file */
46  __u8 di_version; /* inode version */
47  __u8 di_format; /* format of di_c data */
48  __be16 di_onlink; /* old number of links to file */
49  __be32 di_uid; /* owner's user id */
50  __be32 di_gid; /* owner's group id */
51  __be32 di_nlink; /* number of links to file */
52  __be16 di_projid_lo; /* lower part of owner's project id */
53  __be16 di_projid_hi; /* higher part owner's project id */
54  __u8 di_pad[6]; /* unused, zeroed space */
55  __be16 di_flushiter; /* incremented on flush */
56  xfs_timestamp_t di_atime; /* time last accessed */
57  xfs_timestamp_t di_mtime; /* time last modified */
58  xfs_timestamp_t di_ctime; /* time created/inode modified */
59  __be64 di_size; /* number of bytes in file */
60  __be64 di_nblocks; /* # of direct & btree blocks used */
61  __be32 di_extsize; /* basic/minimum extent size for file */
62  __be32 di_nextents; /* number of extents in data fork */
63  __be16 di_anextents; /* number of extents in attribute fork*/
64  __u8 di_forkoff; /* attr fork offs, <<3 for 64b align */
65  __s8 di_aformat; /* format of attr fork's data */
66  __be32 di_dmevmask; /* DMIG event mask */
67  __be16 di_dmstate; /* DMIG state info */
68  __be16 di_flags; /* random flags, XFS_DIFLAG_... */
69  __be32 di_gen; /* generation number */
70 
71  /* di_next_unlinked is the only non-core field in the old dinode */
72  __be32 di_next_unlinked;/* agi unlinked list ptr */
73 } __attribute__((packed)) xfs_dinode_t;
74 
75 #define DI_MAX_FLUSH 0xffff
76 
77 /*
78  * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
79  * Since the pathconf interface is signed, we use 2^31 - 1 instead.
80  * The old inode format had a 16 bit link count, so its maximum is USHRT_MAX.
81  */
82 #define XFS_MAXLINK ((1U << 31) - 1U)
83 #define XFS_MAXLINK_1 65535U
84 
85 /*
86  * Values for di_format
87  */
88 typedef enum xfs_dinode_fmt {
89  XFS_DINODE_FMT_DEV, /* xfs_dev_t */
90  XFS_DINODE_FMT_LOCAL, /* bulk data */
91  XFS_DINODE_FMT_EXTENTS, /* struct xfs_bmbt_rec */
92  XFS_DINODE_FMT_BTREE, /* struct xfs_bmdr_block */
93  XFS_DINODE_FMT_UUID /* uuid_t */
95 
96 /*
97  * Inode minimum and maximum sizes.
98  */
99 #define XFS_DINODE_MIN_LOG 8
100 #define XFS_DINODE_MAX_LOG 11
101 #define XFS_DINODE_MIN_SIZE (1 << XFS_DINODE_MIN_LOG)
102 #define XFS_DINODE_MAX_SIZE (1 << XFS_DINODE_MAX_LOG)
103 
104 /*
105  * Inode size for given fs.
106  */
107 #define XFS_LITINO(mp) \
108  ((int)(((mp)->m_sb.sb_inodesize) - sizeof(struct xfs_dinode)))
109 
110 #define XFS_BROOT_SIZE_ADJ \
111  (XFS_BTREE_LBLOCK_LEN - sizeof(xfs_bmdr_block_t))
112 
113 /*
114  * Inode data & attribute fork sizes, per inode.
115  */
116 #define XFS_DFORK_Q(dip) ((dip)->di_forkoff != 0)
117 #define XFS_DFORK_BOFF(dip) ((int)((dip)->di_forkoff << 3))
118 
119 #define XFS_DFORK_DSIZE(dip,mp) \
120  (XFS_DFORK_Q(dip) ? \
121  XFS_DFORK_BOFF(dip) : \
122  XFS_LITINO(mp))
123 #define XFS_DFORK_ASIZE(dip,mp) \
124  (XFS_DFORK_Q(dip) ? \
125  XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : \
126  0)
127 #define XFS_DFORK_SIZE(dip,mp,w) \
128  ((w) == XFS_DATA_FORK ? \
129  XFS_DFORK_DSIZE(dip, mp) : \
130  XFS_DFORK_ASIZE(dip, mp))
131 
132 /*
133  * Return pointers to the data or attribute forks.
134  */
135 #define XFS_DFORK_DPTR(dip) \
136  ((char *)(dip) + sizeof(struct xfs_dinode))
137 #define XFS_DFORK_APTR(dip) \
138  (XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
139 #define XFS_DFORK_PTR(dip,w) \
140  ((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
141 
142 #define XFS_DFORK_FORMAT(dip,w) \
143  ((w) == XFS_DATA_FORK ? \
144  (dip)->di_format : \
145  (dip)->di_aformat)
146 #define XFS_DFORK_NEXTENTS(dip,w) \
147  ((w) == XFS_DATA_FORK ? \
148  be32_to_cpu((dip)->di_nextents) : \
149  be16_to_cpu((dip)->di_anextents))
150 
151 #define XFS_BUF_TO_DINODE(bp) ((xfs_dinode_t *)((bp)->b_addr))
152 
153 /*
154  * For block and character special files the 32bit dev_t is stored at the
155  * beginning of the data fork.
156  */
157 static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
158 {
159  return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
160 }
161 
162 static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
163 {
164  *(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
165 }
166 
167 /*
168  * Values for di_flags
169  * There should be a one-to-one correspondence between these flags and the
170  * XFS_XFLAG_s.
171  */
172 #define XFS_DIFLAG_REALTIME_BIT 0 /* file's blocks come from rt area */
173 #define XFS_DIFLAG_PREALLOC_BIT 1 /* file space has been preallocated */
174 #define XFS_DIFLAG_NEWRTBM_BIT 2 /* for rtbitmap inode, new format */
175 #define XFS_DIFLAG_IMMUTABLE_BIT 3 /* inode is immutable */
176 #define XFS_DIFLAG_APPEND_BIT 4 /* inode is append-only */
177 #define XFS_DIFLAG_SYNC_BIT 5 /* inode is written synchronously */
178 #define XFS_DIFLAG_NOATIME_BIT 6 /* do not update atime */
179 #define XFS_DIFLAG_NODUMP_BIT 7 /* do not dump */
180 #define XFS_DIFLAG_RTINHERIT_BIT 8 /* create with realtime bit set */
181 #define XFS_DIFLAG_PROJINHERIT_BIT 9 /* create with parents projid */
182 #define XFS_DIFLAG_NOSYMLINKS_BIT 10 /* disallow symlink creation */
183 #define XFS_DIFLAG_EXTSIZE_BIT 11 /* inode extent size allocator hint */
184 #define XFS_DIFLAG_EXTSZINHERIT_BIT 12 /* inherit inode extent size */
185 #define XFS_DIFLAG_NODEFRAG_BIT 13 /* do not reorganize/defragment */
186 #define XFS_DIFLAG_FILESTREAM_BIT 14 /* use filestream allocator */
187 #define XFS_DIFLAG_REALTIME (1 << XFS_DIFLAG_REALTIME_BIT)
188 #define XFS_DIFLAG_PREALLOC (1 << XFS_DIFLAG_PREALLOC_BIT)
189 #define XFS_DIFLAG_NEWRTBM (1 << XFS_DIFLAG_NEWRTBM_BIT)
190 #define XFS_DIFLAG_IMMUTABLE (1 << XFS_DIFLAG_IMMUTABLE_BIT)
191 #define XFS_DIFLAG_APPEND (1 << XFS_DIFLAG_APPEND_BIT)
192 #define XFS_DIFLAG_SYNC (1 << XFS_DIFLAG_SYNC_BIT)
193 #define XFS_DIFLAG_NOATIME (1 << XFS_DIFLAG_NOATIME_BIT)
194 #define XFS_DIFLAG_NODUMP (1 << XFS_DIFLAG_NODUMP_BIT)
195 #define XFS_DIFLAG_RTINHERIT (1 << XFS_DIFLAG_RTINHERIT_BIT)
196 #define XFS_DIFLAG_PROJINHERIT (1 << XFS_DIFLAG_PROJINHERIT_BIT)
197 #define XFS_DIFLAG_NOSYMLINKS (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
198 #define XFS_DIFLAG_EXTSIZE (1 << XFS_DIFLAG_EXTSIZE_BIT)
199 #define XFS_DIFLAG_EXTSZINHERIT (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
200 #define XFS_DIFLAG_NODEFRAG (1 << XFS_DIFLAG_NODEFRAG_BIT)
201 #define XFS_DIFLAG_FILESTREAM (1 << XFS_DIFLAG_FILESTREAM_BIT)
202 
203 #ifdef CONFIG_XFS_RT
204 #define XFS_IS_REALTIME_INODE(ip) ((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME)
205 #else
206 #define XFS_IS_REALTIME_INODE(ip) (0)
207 #endif
208 
209 #define XFS_DIFLAG_ANY \
210  (XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
211  XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
212  XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
213  XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
214  XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
215 
216 #endif /* __XFS_DINODE_H__ */