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 extern const struct xfs_name xfs_name_dot;
26
27 static inline bool
xfs_dir2_samename(const struct xfs_name * n1,const struct xfs_name * n2)28 xfs_dir2_samename(
29 const struct xfs_name *n1,
30 const struct xfs_name *n2)
31 {
32 if (n1 == n2)
33 return true;
34 if (n1->len != n2->len)
35 return false;
36 return !memcmp(n1->name, n2->name, n1->len);
37 }
38
39 enum xfs_dir2_fmt {
40 XFS_DIR2_FMT_SF,
41 XFS_DIR2_FMT_BLOCK,
42 XFS_DIR2_FMT_LEAF,
43 XFS_DIR2_FMT_NODE,
44 XFS_DIR2_FMT_ERROR,
45 };
46
47 enum xfs_dir2_fmt xfs_dir2_format(struct xfs_da_args *args, int *error);
48
49 /*
50 * Convert inode mode to directory entry filetype
51 */
52 extern unsigned char xfs_mode_to_ftype(int mode);
53
54 /*
55 * Generic directory interface routines
56 */
57 extern void xfs_dir_startup(void);
58 extern int xfs_da_mount(struct xfs_mount *mp);
59 extern void xfs_da_unmount(struct xfs_mount *mp);
60
61 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
62 struct xfs_inode *pdp);
63 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
64 const struct xfs_name *name, xfs_ino_t inum,
65 xfs_extlen_t tot);
66 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
67 const struct xfs_name *name, xfs_ino_t *inum,
68 struct xfs_name *ci_name);
69 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
70 const struct xfs_name *name, xfs_ino_t ino,
71 xfs_extlen_t tot);
72 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
73 const struct xfs_name *name, xfs_ino_t inum,
74 xfs_extlen_t tot);
75 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
76 const struct xfs_name *name);
77
78 int xfs_dir_lookup_args(struct xfs_da_args *args);
79 int xfs_dir_createname_args(struct xfs_da_args *args);
80 int xfs_dir_removename_args(struct xfs_da_args *args);
81 int xfs_dir_replace_args(struct xfs_da_args *args);
82
83 /*
84 * Direct call from the bmap code, bypassing the generic directory layer.
85 */
86 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
87
88 /*
89 * Interface routines used by userspace utilities
90 */
91 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
92 struct xfs_buf *bp);
93
94 extern void xfs_dir2_data_freescan(struct xfs_mount *mp,
95 struct xfs_dir2_data_hdr *hdr, int *loghead);
96 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
97 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
98 extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
99 struct xfs_buf *bp);
100 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
101 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
102 extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
103 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
104 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
105 extern int xfs_dir2_data_use_free(struct xfs_da_args *args,
106 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
107 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
108 int *needlogp, int *needscanp);
109
110 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
111 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
112 struct xfs_dir2_data_unused *dup);
113
114 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
115
116 xfs_failaddr_t xfs_dir3_leaf_header_check(struct xfs_buf *bp, xfs_ino_t owner);
117 xfs_failaddr_t xfs_dir3_data_header_check(struct xfs_buf *bp, xfs_ino_t owner);
118 xfs_failaddr_t xfs_dir3_block_header_check(struct xfs_buf *bp, xfs_ino_t owner);
119
120 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
121 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
122 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
123 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
124 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
125
126 /*
127 * Directory offset/block conversion functions.
128 *
129 * DB blocks here are logical directory block numbers, not filesystem blocks.
130 */
131
132 /*
133 * Convert dataptr to byte in file space
134 */
135 static inline xfs_dir2_off_t
xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)136 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
137 {
138 return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
139 }
140
141 /*
142 * Convert byte in file space to dataptr. It had better be aligned.
143 */
144 static inline xfs_dir2_dataptr_t
xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)145 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
146 {
147 return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
148 }
149
150 /*
151 * Convert byte in space to (DB) block
152 */
153 static inline xfs_dir2_db_t
xfs_dir2_byte_to_db(struct xfs_da_geometry * geo,xfs_dir2_off_t by)154 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
155 {
156 return (xfs_dir2_db_t)(by >> geo->blklog);
157 }
158
159 /*
160 * Convert dataptr to a block number
161 */
162 static inline xfs_dir2_db_t
xfs_dir2_dataptr_to_db(struct xfs_da_geometry * geo,xfs_dir2_dataptr_t dp)163 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
164 {
165 return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
166 }
167
168 /*
169 * Convert byte in space to offset in a block
170 */
171 static inline xfs_dir2_data_aoff_t
xfs_dir2_byte_to_off(struct xfs_da_geometry * geo,xfs_dir2_off_t by)172 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
173 {
174 return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
175 }
176
177 /*
178 * Convert dataptr to a byte offset in a block
179 */
180 static inline xfs_dir2_data_aoff_t
xfs_dir2_dataptr_to_off(struct xfs_da_geometry * geo,xfs_dir2_dataptr_t dp)181 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
182 {
183 return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
184 }
185
186 /*
187 * Convert block and offset to byte in space
188 */
189 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)190 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
191 xfs_dir2_data_aoff_t o)
192 {
193 return ((xfs_dir2_off_t)db << geo->blklog) + o;
194 }
195
196 /*
197 * Convert block (DB) to block (dablk)
198 */
199 static inline xfs_dablk_t
xfs_dir2_db_to_da(struct xfs_da_geometry * geo,xfs_dir2_db_t db)200 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
201 {
202 return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
203 }
204
205 /*
206 * Convert byte in space to (DA) block
207 */
208 static inline xfs_dablk_t
xfs_dir2_byte_to_da(struct xfs_da_geometry * geo,xfs_dir2_off_t by)209 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
210 {
211 return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
212 }
213
214 /*
215 * Convert block and offset to dataptr
216 */
217 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)218 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
219 xfs_dir2_data_aoff_t o)
220 {
221 return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
222 }
223
224 /*
225 * Convert block (dablk) to block (DB)
226 */
227 static inline xfs_dir2_db_t
xfs_dir2_da_to_db(struct xfs_da_geometry * geo,xfs_dablk_t da)228 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
229 {
230 return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
231 }
232
233 /*
234 * Convert block (dablk) to byte offset in space
235 */
236 static inline xfs_dir2_off_t
xfs_dir2_da_to_byte(struct xfs_da_geometry * geo,xfs_dablk_t da)237 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
238 {
239 return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
240 }
241
242 /*
243 * Directory tail pointer accessor functions. Based on block geometry.
244 */
245 static inline struct xfs_dir2_block_tail *
xfs_dir2_block_tail_p(struct xfs_da_geometry * geo,struct xfs_dir2_data_hdr * hdr)246 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
247 {
248 return ((struct xfs_dir2_block_tail *)
249 ((char *)hdr + geo->blksize)) - 1;
250 }
251
252 static inline struct xfs_dir2_leaf_tail *
xfs_dir2_leaf_tail_p(struct xfs_da_geometry * geo,struct xfs_dir2_leaf * lp)253 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
254 {
255 return (struct xfs_dir2_leaf_tail *)
256 ((char *)lp + geo->blksize -
257 sizeof(struct xfs_dir2_leaf_tail));
258 }
259
260 /*
261 * The Linux API doesn't pass down the total size of the buffer
262 * we read into down to the filesystem. With the filldir concept
263 * it's not needed for correct information, but the XFS dir2 leaf
264 * code wants an estimate of the buffer size to calculate it's
265 * readahead window and size the buffers used for mapping to
266 * physical blocks.
267 *
268 * Try to give it an estimate that's good enough, maybe at some
269 * point we can change the ->readdir prototype to include the
270 * buffer size. For now we use the current glibc buffer size.
271 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
272 */
273 #define XFS_READDIR_BUFSIZE (32768)
274
275 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
276 unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo,
277 struct xfs_dir2_data_hdr *hdr);
278 bool xfs_dir2_namecheck(const void *name, size_t length);
279
280 /*
281 * The "ascii-ci" feature was created to speed up case-insensitive lookups for
282 * a Samba product. Because of the inherent problems with CI and UTF-8
283 * encoding, etc, it was decided that Samba would be configured to export
284 * latin1/iso 8859-1 encodings as that covered >90% of the target markets for
285 * the product. Hence the "ascii-ci" casefolding code could be encoded into
286 * the XFS directory operations and remove all the overhead of casefolding from
287 * Samba.
288 *
289 * To provide consistent hashing behavior between the userspace and kernel,
290 * these functions prepare names for hashing by transforming specific bytes
291 * to other bytes. Robustness with other encodings is not guaranteed.
292 */
xfs_ascii_ci_need_xfrm(unsigned char c)293 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c)
294 {
295 if (c >= 0x41 && c <= 0x5a) /* A-Z */
296 return true;
297 if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */
298 return true;
299 if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */
300 return true;
301 return false;
302 }
303
xfs_ascii_ci_xfrm(unsigned char c)304 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c)
305 {
306 if (xfs_ascii_ci_need_xfrm(c))
307 c -= 'A' - 'a';
308 return c;
309 }
310
311 struct xfs_dir_update_params {
312 const struct xfs_inode *dp;
313 const struct xfs_inode *ip;
314 const struct xfs_name *name;
315 int delta;
316 };
317
318 #ifdef CONFIG_XFS_LIVE_HOOKS
319 void xfs_dir_update_hook(struct xfs_inode *dp, struct xfs_inode *ip,
320 int delta, const struct xfs_name *name);
321
322 struct xfs_dir_hook {
323 struct xfs_hook dirent_hook;
324 };
325
326 void xfs_dir_hook_disable(void);
327 void xfs_dir_hook_enable(void);
328
329 int xfs_dir_hook_add(struct xfs_mount *mp, struct xfs_dir_hook *hook);
330 void xfs_dir_hook_del(struct xfs_mount *mp, struct xfs_dir_hook *hook);
331 void xfs_dir_hook_setup(struct xfs_dir_hook *hook, notifier_fn_t mod_fn);
332 #else
333 # define xfs_dir_update_hook(dp, ip, delta, name) ((void)0)
334 #endif /* CONFIG_XFS_LIVE_HOOKS */
335
336 struct xfs_parent_args;
337
338 struct xfs_dir_update {
339 struct xfs_inode *dp;
340 const struct xfs_name *name;
341 struct xfs_inode *ip;
342 struct xfs_parent_args *ppargs;
343 };
344
345 int xfs_dir_create_child(struct xfs_trans *tp, unsigned int resblks,
346 struct xfs_dir_update *du);
347 int xfs_dir_add_child(struct xfs_trans *tp, unsigned int resblks,
348 struct xfs_dir_update *du);
349 int xfs_dir_remove_child(struct xfs_trans *tp, unsigned int resblks,
350 struct xfs_dir_update *du);
351
352 int xfs_dir_exchange_children(struct xfs_trans *tp, struct xfs_dir_update *du1,
353 struct xfs_dir_update *du2, unsigned int spaceres);
354 int xfs_dir_rename_children(struct xfs_trans *tp, struct xfs_dir_update *du_src,
355 struct xfs_dir_update *du_tgt, unsigned int spaceres,
356 struct xfs_dir_update *du_wip);
357
358 #endif /* __XFS_DIR2_H__ */
359