1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6 #ifndef __XFS_DIR2_H__
7 #define __XFS_DIR2_H__
8
9 #include "xfs_da_format.h"
10 #include "xfs_da_btree.h"
11
12 struct xfs_da_args;
13 struct xfs_inode;
14 struct xfs_mount;
15 struct xfs_trans;
16 struct xfs_dir2_sf_hdr;
17 struct xfs_dir2_sf_entry;
18 struct xfs_dir2_data_hdr;
19 struct xfs_dir2_data_entry;
20 struct xfs_dir2_data_unused;
21 struct xfs_dir3_icfree_hdr;
22 struct xfs_dir3_icleaf_hdr;
23
24 extern const struct xfs_name xfs_name_dotdot;
25
26 /*
27 * Convert inode mode to directory entry filetype
28 */
29 extern unsigned char xfs_mode_to_ftype(int mode);
30
31 /*
32 * Generic directory interface routines
33 */
34 extern void xfs_dir_startup(void);
35 extern int xfs_da_mount(struct xfs_mount *mp);
36 extern void xfs_da_unmount(struct xfs_mount *mp);
37
38 extern int xfs_dir_isempty(struct xfs_inode *dp);
39 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
40 struct xfs_inode *pdp);
41 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
42 const struct xfs_name *name, xfs_ino_t inum,
43 xfs_extlen_t tot);
44 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
45 const struct xfs_name *name, xfs_ino_t *inum,
46 struct xfs_name *ci_name);
47 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
48 struct xfs_name *name, xfs_ino_t ino,
49 xfs_extlen_t tot);
50 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
51 const struct xfs_name *name, xfs_ino_t inum,
52 xfs_extlen_t tot);
53 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
54 struct xfs_name *name);
55
56 /*
57 * Direct call from the bmap code, bypassing the generic directory layer.
58 */
59 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
60
61 /*
62 * Interface routines used by userspace utilities
63 */
64 extern int xfs_dir2_isblock(struct xfs_da_args *args, bool *isblock);
65 extern int xfs_dir2_isleaf(struct xfs_da_args *args, bool *isleaf);
66 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
67 struct xfs_buf *bp);
68
69 extern void xfs_dir2_data_freescan(struct xfs_mount *mp,
70 struct xfs_dir2_data_hdr *hdr, int *loghead);
71 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
72 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
73 extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
74 struct xfs_buf *bp);
75 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
76 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
77 extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
78 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
79 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
80 extern int xfs_dir2_data_use_free(struct xfs_da_args *args,
81 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
82 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
83 int *needlogp, int *needscanp);
84
85 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
86 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
87 struct xfs_dir2_data_unused *dup);
88
89 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
90
91 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
92 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
93 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
94 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
95 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
96
97 /*
98 * Directory offset/block conversion functions.
99 *
100 * DB blocks here are logical directory block numbers, not filesystem blocks.
101 */
102
103 /*
104 * Convert dataptr to byte in file space
105 */
106 static inline xfs_dir2_off_t
xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)107 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
108 {
109 return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
110 }
111
112 /*
113 * Convert byte in file space to dataptr. It had better be aligned.
114 */
115 static inline xfs_dir2_dataptr_t
xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)116 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
117 {
118 return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
119 }
120
121 /*
122 * Convert byte in space to (DB) block
123 */
124 static inline xfs_dir2_db_t
xfs_dir2_byte_to_db(struct xfs_da_geometry * geo,xfs_dir2_off_t by)125 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
126 {
127 return (xfs_dir2_db_t)(by >> geo->blklog);
128 }
129
130 /*
131 * Convert dataptr to a block number
132 */
133 static inline xfs_dir2_db_t
xfs_dir2_dataptr_to_db(struct xfs_da_geometry * geo,xfs_dir2_dataptr_t dp)134 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
135 {
136 return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
137 }
138
139 /*
140 * Convert byte in space to offset in a block
141 */
142 static inline xfs_dir2_data_aoff_t
xfs_dir2_byte_to_off(struct xfs_da_geometry * geo,xfs_dir2_off_t by)143 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
144 {
145 return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
146 }
147
148 /*
149 * Convert dataptr to a byte offset in a block
150 */
151 static inline xfs_dir2_data_aoff_t
xfs_dir2_dataptr_to_off(struct xfs_da_geometry * geo,xfs_dir2_dataptr_t dp)152 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
153 {
154 return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
155 }
156
157 /*
158 * Convert block and offset to byte in space
159 */
160 static inline xfs_dir2_off_t
xfs_dir2_db_off_to_byte(struct xfs_da_geometry * geo,xfs_dir2_db_t db,xfs_dir2_data_aoff_t o)161 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
162 xfs_dir2_data_aoff_t o)
163 {
164 return ((xfs_dir2_off_t)db << geo->blklog) + o;
165 }
166
167 /*
168 * Convert block (DB) to block (dablk)
169 */
170 static inline xfs_dablk_t
xfs_dir2_db_to_da(struct xfs_da_geometry * geo,xfs_dir2_db_t db)171 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
172 {
173 return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
174 }
175
176 /*
177 * Convert byte in space to (DA) block
178 */
179 static inline xfs_dablk_t
xfs_dir2_byte_to_da(struct xfs_da_geometry * geo,xfs_dir2_off_t by)180 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
181 {
182 return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
183 }
184
185 /*
186 * Convert block and offset to dataptr
187 */
188 static inline xfs_dir2_dataptr_t
xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry * geo,xfs_dir2_db_t db,xfs_dir2_data_aoff_t o)189 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
190 xfs_dir2_data_aoff_t o)
191 {
192 return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
193 }
194
195 /*
196 * Convert block (dablk) to block (DB)
197 */
198 static inline xfs_dir2_db_t
xfs_dir2_da_to_db(struct xfs_da_geometry * geo,xfs_dablk_t da)199 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
200 {
201 return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
202 }
203
204 /*
205 * Convert block (dablk) to byte offset in space
206 */
207 static inline xfs_dir2_off_t
xfs_dir2_da_to_byte(struct xfs_da_geometry * geo,xfs_dablk_t da)208 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
209 {
210 return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
211 }
212
213 /*
214 * Directory tail pointer accessor functions. Based on block geometry.
215 */
216 static inline struct xfs_dir2_block_tail *
xfs_dir2_block_tail_p(struct xfs_da_geometry * geo,struct xfs_dir2_data_hdr * hdr)217 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
218 {
219 return ((struct xfs_dir2_block_tail *)
220 ((char *)hdr + geo->blksize)) - 1;
221 }
222
223 static inline struct xfs_dir2_leaf_tail *
xfs_dir2_leaf_tail_p(struct xfs_da_geometry * geo,struct xfs_dir2_leaf * lp)224 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
225 {
226 return (struct xfs_dir2_leaf_tail *)
227 ((char *)lp + geo->blksize -
228 sizeof(struct xfs_dir2_leaf_tail));
229 }
230
231 /*
232 * The Linux API doesn't pass down the total size of the buffer
233 * we read into down to the filesystem. With the filldir concept
234 * it's not needed for correct information, but the XFS dir2 leaf
235 * code wants an estimate of the buffer size to calculate it's
236 * readahead window and size the buffers used for mapping to
237 * physical blocks.
238 *
239 * Try to give it an estimate that's good enough, maybe at some
240 * point we can change the ->readdir prototype to include the
241 * buffer size. For now we use the current glibc buffer size.
242 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
243 */
244 #define XFS_READDIR_BUFSIZE (32768)
245
246 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
247 unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo,
248 struct xfs_dir2_data_hdr *hdr);
249 bool xfs_dir2_namecheck(const void *name, size_t length);
250
251 /*
252 * The "ascii-ci" feature was created to speed up case-insensitive lookups for
253 * a Samba product. Because of the inherent problems with CI and UTF-8
254 * encoding, etc, it was decided that Samba would be configured to export
255 * latin1/iso 8859-1 encodings as that covered >90% of the target markets for
256 * the product. Hence the "ascii-ci" casefolding code could be encoded into
257 * the XFS directory operations and remove all the overhead of casefolding from
258 * Samba.
259 *
260 * To provide consistent hashing behavior between the userspace and kernel,
261 * these functions prepare names for hashing by transforming specific bytes
262 * to other bytes. Robustness with other encodings is not guaranteed.
263 */
xfs_ascii_ci_need_xfrm(unsigned char c)264 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c)
265 {
266 if (c >= 0x41 && c <= 0x5a) /* A-Z */
267 return true;
268 if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */
269 return true;
270 if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */
271 return true;
272 return false;
273 }
274
xfs_ascii_ci_xfrm(unsigned char c)275 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c)
276 {
277 if (xfs_ascii_ci_need_xfrm(c))
278 c -= 'A' - 'a';
279 return c;
280 }
281
282 #endif /* __XFS_DIR2_H__ */
283