tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * Copyright (c) 2000-2001,2005 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_DIR2_SF_H__
19#define __XFS_DIR2_SF_H__
20
21/*
22 * Directory layout when stored internal to an inode.
23 *
24 * Small directories are packed as tightly as possible so as to
25 * fit into the literal area of the inode.
26 */
27
28struct uio;
29struct xfs_dabuf;
30struct xfs_da_args;
31struct xfs_dir2_block;
32struct xfs_inode;
33struct xfs_mount;
34struct xfs_trans;
35
36/*
37 * Maximum size of a shortform directory.
38 */
39#define XFS_DIR2_SF_MAX_SIZE \
40 (XFS_DINODE_MAX_SIZE - (uint)sizeof(xfs_dinode_core_t) - \
41 (uint)sizeof(xfs_agino_t))
42
43/*
44 * Inode number stored as 8 8-bit values.
45 */
46typedef struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
47
48/*
49 * Inode number stored as 4 8-bit values.
50 * Works a lot of the time, when all the inode numbers in a directory
51 * fit in 32 bits.
52 */
53typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
54
55typedef union {
56 xfs_dir2_ino8_t i8;
57 xfs_dir2_ino4_t i4;
58} xfs_dir2_inou_t;
59#define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL)
60
61/*
62 * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
63 * Only need 16 bits, this is the byte offset into the single block form.
64 */
65typedef struct { __uint8_t i[2]; } xfs_dir2_sf_off_t;
66
67/*
68 * The parent directory has a dedicated field, and the self-pointer must
69 * be calculated on the fly.
70 *
71 * Entries are packed toward the top as tightly as possible. The header
72 * and the elements must be memcpy'd out into a work area to get correct
73 * alignment for the inode number fields.
74 */
75typedef struct xfs_dir2_sf_hdr {
76 __uint8_t count; /* count of entries */
77 __uint8_t i8count; /* count of 8-byte inode #s */
78 xfs_dir2_inou_t parent; /* parent dir inode number */
79} xfs_dir2_sf_hdr_t;
80
81typedef struct xfs_dir2_sf_entry {
82 __uint8_t namelen; /* actual name length */
83 xfs_dir2_sf_off_t offset; /* saved offset */
84 __uint8_t name[1]; /* name, variable size */
85 xfs_dir2_inou_t inumber; /* inode number, var. offset */
86} xfs_dir2_sf_entry_t;
87
88typedef struct xfs_dir2_sf {
89 xfs_dir2_sf_hdr_t hdr; /* shortform header */
90 xfs_dir2_sf_entry_t list[1]; /* shortform entries */
91} xfs_dir2_sf_t;
92
93static inline int xfs_dir2_sf_hdr_size(int i8count)
94{
95 return ((uint)sizeof(xfs_dir2_sf_hdr_t) - \
96 ((i8count) == 0) * \
97 ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)));
98}
99
100static inline xfs_dir2_inou_t *xfs_dir2_sf_inumberp(xfs_dir2_sf_entry_t *sfep)
101{
102 return (xfs_dir2_inou_t *)&(sfep)->name[(sfep)->namelen];
103}
104
105static inline xfs_intino_t
106xfs_dir2_sf_get_inumber(xfs_dir2_sf_t *sfp, xfs_dir2_inou_t *from)
107{
108 return ((sfp)->hdr.i8count == 0 ? \
109 (xfs_intino_t)XFS_GET_DIR_INO4((from)->i4) : \
110 (xfs_intino_t)XFS_GET_DIR_INO8((from)->i8));
111}
112
113static inline void xfs_dir2_sf_put_inumber(xfs_dir2_sf_t *sfp, xfs_ino_t *from,
114 xfs_dir2_inou_t *to)
115{
116 if ((sfp)->hdr.i8count == 0)
117 XFS_PUT_DIR_INO4(*(from), (to)->i4);
118 else
119 XFS_PUT_DIR_INO8(*(from), (to)->i8);
120}
121
122static inline xfs_dir2_data_aoff_t
123xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep)
124{
125 return INT_GET_UNALIGNED_16_BE(&(sfep)->offset.i);
126}
127
128static inline void
129xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off)
130{
131 INT_SET_UNALIGNED_16_BE(&(sfep)->offset.i, off);
132}
133
134static inline int xfs_dir2_sf_entsize_byname(xfs_dir2_sf_t *sfp, int len)
135{
136 return ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (len) - \
137 ((sfp)->hdr.i8count == 0) * \
138 ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)));
139}
140
141static inline int
142xfs_dir2_sf_entsize_byentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep)
143{
144 return ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (sfep)->namelen - \
145 ((sfp)->hdr.i8count == 0) * \
146 ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)));
147}
148
149static inline xfs_dir2_sf_entry_t *xfs_dir2_sf_firstentry(xfs_dir2_sf_t *sfp)
150{
151 return ((xfs_dir2_sf_entry_t *) \
152 ((char *)(sfp) + xfs_dir2_sf_hdr_size(sfp->hdr.i8count)));
153}
154
155static inline xfs_dir2_sf_entry_t *
156xfs_dir2_sf_nextentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep)
157{
158 return ((xfs_dir2_sf_entry_t *) \
159 ((char *)(sfep) + xfs_dir2_sf_entsize_byentry(sfp,sfep)));
160}
161
162/*
163 * Functions.
164 */
165extern int xfs_dir2_block_sfsize(struct xfs_inode *dp,
166 struct xfs_dir2_block *block,
167 xfs_dir2_sf_hdr_t *sfhp);
168extern int xfs_dir2_block_to_sf(struct xfs_da_args *args, struct xfs_dabuf *bp,
169 int size, xfs_dir2_sf_hdr_t *sfhp);
170extern int xfs_dir2_sf_addname(struct xfs_da_args *args);
171extern int xfs_dir2_sf_create(struct xfs_da_args *args, xfs_ino_t pino);
172extern int xfs_dir2_sf_getdents(struct xfs_inode *dp, void *dirent,
173 xfs_off_t *offset, filldir_t filldir);
174extern int xfs_dir2_sf_lookup(struct xfs_da_args *args);
175extern int xfs_dir2_sf_removename(struct xfs_da_args *args);
176extern int xfs_dir2_sf_replace(struct xfs_da_args *args);
177
178#endif /* __XFS_DIR2_SF_H__ */