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-rw-r--r--fs/xfs/xfs_dir_leaf.h231
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diff --git a/fs/xfs/xfs_dir_leaf.h b/fs/xfs/xfs_dir_leaf.h
index 7ca5845195d5..e69de29bb2d1 100644
--- a/fs/xfs/xfs_dir_leaf.h
+++ b/fs/xfs/xfs_dir_leaf.h
@@ -1,231 +0,0 @@
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_DIR_LEAF_H__
19#define __XFS_DIR_LEAF_H__
20
21/*
22 * Directory layout, internal structure, access macros, etc.
23 *
24 * Large directories are structured around Btrees where all the data
25 * elements are in the leaf nodes. Filenames are hashed into an int,
26 * then that int is used as the index into the Btree. Since the hashval
27 * of a filename may not be unique, we may have duplicate keys. The
28 * internal links in the Btree are logical block offsets into the file.
29 */
30
31struct uio;
32struct xfs_bmap_free;
33struct xfs_dabuf;
34struct xfs_da_args;
35struct xfs_da_state;
36struct xfs_da_state_blk;
37struct xfs_dir_put_args;
38struct xfs_inode;
39struct xfs_mount;
40struct xfs_trans;
41
42/*========================================================================
43 * Directory Structure when equal to XFS_LBSIZE(mp) bytes.
44 *========================================================================*/
45
46/*
47 * This is the structure of the leaf nodes in the Btree.
48 *
49 * Struct leaf_entry's are packed from the top. Names grow from the bottom
50 * but are not packed. The freemap contains run-length-encoded entries
51 * for the free bytes after the leaf_entry's, but only the N largest such,
52 * smaller runs are dropped. When the freemap doesn't show enough space
53 * for an allocation, we compact the namelist area and try again. If we
54 * still don't have enough space, then we have to split the block.
55 *
56 * Since we have duplicate hash keys, for each key that matches, compare
57 * the actual string. The root and intermediate node search always takes
58 * the first-in-the-block key match found, so we should only have to work
59 * "forw"ard. If none matches, continue with the "forw"ard leaf nodes
60 * until the hash key changes or the filename is found.
61 *
62 * The parent directory and the self-pointer are explicitly represented
63 * (ie: there are entries for "." and "..").
64 *
65 * Note that the count being a __uint16_t limits us to something like a
66 * blocksize of 1.3MB in the face of worst case (short) filenames.
67 */
68#define XFS_DIR_LEAF_MAPSIZE 3 /* how many freespace slots */
69
70typedef struct xfs_dir_leaf_map { /* RLE map of free bytes */
71 __be16 base; /* base of free region */
72 __be16 size; /* run length of free region */
73} xfs_dir_leaf_map_t;
74
75typedef struct xfs_dir_leaf_hdr { /* constant-structure header block */
76 xfs_da_blkinfo_t info; /* block type, links, etc. */
77 __be16 count; /* count of active leaf_entry's */
78 __be16 namebytes; /* num bytes of name strings stored */
79 __be16 firstused; /* first used byte in name area */
80 __u8 holes; /* != 0 if blk needs compaction */
81 __u8 pad1;
82 xfs_dir_leaf_map_t freemap[XFS_DIR_LEAF_MAPSIZE];
83} xfs_dir_leaf_hdr_t;
84
85typedef struct xfs_dir_leaf_entry { /* sorted on key, not name */
86 __be32 hashval; /* hash value of name */
87 __be16 nameidx; /* index into buffer of name */
88 __u8 namelen; /* length of name string */
89 __u8 pad2;
90} xfs_dir_leaf_entry_t;
91
92typedef struct xfs_dir_leaf_name {
93 xfs_dir_ino_t inumber; /* inode number for this key */
94 __uint8_t name[1]; /* name string itself */
95} xfs_dir_leaf_name_t;
96
97typedef struct xfs_dir_leafblock {
98 xfs_dir_leaf_hdr_t hdr; /* constant-structure header block */
99 xfs_dir_leaf_entry_t entries[1]; /* var sized array */
100 xfs_dir_leaf_name_t namelist[1]; /* grows from bottom of buf */
101} xfs_dir_leafblock_t;
102
103/*
104 * Length of name for which a 512-byte block filesystem
105 * can get a double split.
106 */
107#define XFS_DIR_LEAF_CAN_DOUBLE_SPLIT_LEN \
108 (512 - (uint)sizeof(xfs_dir_leaf_hdr_t) - \
109 (uint)sizeof(xfs_dir_leaf_entry_t) * 2 - \
110 (uint)sizeof(xfs_dir_leaf_name_t) * 2 - (MAXNAMELEN - 2) + 1 + 1)
111
112typedef int (*xfs_dir_put_t)(struct xfs_dir_put_args *pa);
113
114typedef union {
115 xfs_off_t o; /* offset (cookie) */
116 /*
117 * Watch the order here (endian-ness dependent).
118 */
119 struct {
120#ifndef XFS_NATIVE_HOST
121 xfs_dahash_t h; /* hash value */
122 __uint32_t be; /* block and entry */
123#else
124 __uint32_t be; /* block and entry */
125 xfs_dahash_t h; /* hash value */
126#endif /* XFS_NATIVE_HOST */
127 } s;
128} xfs_dircook_t;
129
130#define XFS_PUT_COOKIE(c,mp,bno,entry,hash) \
131 ((c).s.be = XFS_DA_MAKE_BNOENTRY(mp, bno, entry), (c).s.h = (hash))
132
133typedef struct xfs_dir_put_args {
134 xfs_dircook_t cook; /* cookie of (next) entry */
135 xfs_intino_t ino; /* inode number */
136 struct xfs_dirent *dbp; /* buffer pointer */
137 char *name; /* directory entry name */
138 int namelen; /* length of name */
139 int done; /* output: set if value was stored */
140 xfs_dir_put_t put; /* put function ptr (i/o) */
141 struct uio *uio; /* uio control structure */
142} xfs_dir_put_args_t;
143
144#define XFS_DIR_LEAF_ENTSIZE_BYNAME(len) \
145 xfs_dir_leaf_entsize_byname(len)
146static inline int xfs_dir_leaf_entsize_byname(int len)
147{
148 return (uint)sizeof(xfs_dir_leaf_name_t)-1 + len;
149}
150
151#define XFS_DIR_LEAF_ENTSIZE_BYENTRY(entry) \
152 xfs_dir_leaf_entsize_byentry(entry)
153static inline int xfs_dir_leaf_entsize_byentry(xfs_dir_leaf_entry_t *entry)
154{
155 return (uint)sizeof(xfs_dir_leaf_name_t)-1 + (entry)->namelen;
156}
157
158#define XFS_DIR_LEAF_NAMESTRUCT(leafp,offset) \
159 xfs_dir_leaf_namestruct(leafp,offset)
160static inline xfs_dir_leaf_name_t *
161xfs_dir_leaf_namestruct(xfs_dir_leafblock_t *leafp, int offset)
162{
163 return (xfs_dir_leaf_name_t *)&((char *)(leafp))[offset];
164}
165
166/*========================================================================
167 * Function prototypes for the kernel.
168 *========================================================================*/
169
170/*
171 * Internal routines when dirsize < XFS_LITINO(mp).
172 */
173int xfs_dir_shortform_create(struct xfs_da_args *args, xfs_ino_t parent);
174int xfs_dir_shortform_addname(struct xfs_da_args *args);
175int xfs_dir_shortform_lookup(struct xfs_da_args *args);
176int xfs_dir_shortform_to_leaf(struct xfs_da_args *args);
177int xfs_dir_shortform_removename(struct xfs_da_args *args);
178int xfs_dir_shortform_getdents(struct xfs_inode *dp, struct uio *uio, int *eofp,
179 struct xfs_dirent *dbp, xfs_dir_put_t put);
180int xfs_dir_shortform_replace(struct xfs_da_args *args);
181
182/*
183 * Internal routines when dirsize == XFS_LBSIZE(mp).
184 */
185int xfs_dir_leaf_to_node(struct xfs_da_args *args);
186int xfs_dir_leaf_to_shortform(struct xfs_da_args *args);
187
188/*
189 * Routines used for growing the Btree.
190 */
191int xfs_dir_leaf_split(struct xfs_da_state *state,
192 struct xfs_da_state_blk *oldblk,
193 struct xfs_da_state_blk *newblk);
194int xfs_dir_leaf_add(struct xfs_dabuf *leaf_buffer,
195 struct xfs_da_args *args, int insertion_index);
196int xfs_dir_leaf_addname(struct xfs_da_args *args);
197int xfs_dir_leaf_lookup_int(struct xfs_dabuf *leaf_buffer,
198 struct xfs_da_args *args,
199 int *index_found_at);
200int xfs_dir_leaf_remove(struct xfs_trans *trans,
201 struct xfs_dabuf *leaf_buffer,
202 int index_to_remove);
203int xfs_dir_leaf_getdents_int(struct xfs_dabuf *bp, struct xfs_inode *dp,
204 xfs_dablk_t bno, struct uio *uio,
205 int *eobp, struct xfs_dirent *dbp,
206 xfs_dir_put_t put, xfs_daddr_t nextda);
207
208/*
209 * Routines used for shrinking the Btree.
210 */
211int xfs_dir_leaf_toosmall(struct xfs_da_state *state, int *retval);
212void xfs_dir_leaf_unbalance(struct xfs_da_state *state,
213 struct xfs_da_state_blk *drop_blk,
214 struct xfs_da_state_blk *save_blk);
215
216/*
217 * Utility routines.
218 */
219uint xfs_dir_leaf_lasthash(struct xfs_dabuf *bp, int *count);
220int xfs_dir_leaf_order(struct xfs_dabuf *leaf1_bp,
221 struct xfs_dabuf *leaf2_bp);
222int xfs_dir_put_dirent64_direct(xfs_dir_put_args_t *pa);
223int xfs_dir_put_dirent64_uio(xfs_dir_put_args_t *pa);
224int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
225
226/*
227 * Global data.
228 */
229extern xfs_dahash_t xfs_dir_hash_dot, xfs_dir_hash_dotdot;
230
231#endif /* __XFS_DIR_LEAF_H__ */
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-04 05:30:02 -0500