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_isempty(struct xfs_inode *dp);
62 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
63 struct xfs_inode *pdp);
64 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
65 const struct xfs_name *name, xfs_ino_t inum,
66 xfs_extlen_t tot);
67 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
68 const struct xfs_name *name, xfs_ino_t *inum,
69 struct xfs_name *ci_name);
70 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
71 const struct xfs_name *name, xfs_ino_t ino,
72 xfs_extlen_t tot);
73 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
74 const struct xfs_name *name, xfs_ino_t inum,
75 xfs_extlen_t tot);
76 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
77 const struct xfs_name *name);
78
79 int xfs_dir_lookup_args(struct xfs_da_args *args);
80 int xfs_dir_createname_args(struct xfs_da_args *args);
81 int xfs_dir_removename_args(struct xfs_da_args *args);
82 int xfs_dir_replace_args(struct xfs_da_args *args);
83
84 /*
85 * Direct call from the bmap code, bypassing the generic directory layer.
86 */
87 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
88
89 /*
90 * Interface routines used by userspace utilities
91 */
92 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
93 struct xfs_buf *bp);
94
95 extern void xfs_dir2_data_freescan(struct xfs_mount *mp,
96 struct xfs_dir2_data_hdr *hdr, int *loghead);
97 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
98 struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
99 extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
100 struct xfs_buf *bp);
101 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
102 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
103 extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
104 struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
105 xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
106 extern int xfs_dir2_data_use_free(struct xfs_da_args *args,
107 struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
108 xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
109 int *needlogp, int *needscanp);
110
111 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
112 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
113 struct xfs_dir2_data_unused *dup);
114
115 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
116
117 xfs_failaddr_t xfs_dir3_leaf_header_check(struct xfs_buf *bp, xfs_ino_t owner);
118 xfs_failaddr_t xfs_dir3_data_header_check(struct xfs_buf *bp, xfs_ino_t owner);
119 xfs_failaddr_t xfs_dir3_block_header_check(struct xfs_buf *bp, xfs_ino_t owner);
120
121 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
122 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
123 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
124 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
125 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
126
127 /*
128 * Directory offset/block conversion functions.
129 *
130 * DB blocks here are logical directory block numbers, not filesystem blocks.
131 */
132
133 /*
134 * Convert dataptr to byte in file space
135 */
136 static inline xfs_dir2_off_t
xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)137 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
138 {
139 return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
140 }
141
142 /*
143 * Convert byte in file space to dataptr. It had better be aligned.
144 */
145 static inline xfs_dir2_dataptr_t
xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)146 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
147 {
148 return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
149 }
150
151 /*
152 * Convert byte in space to (DB) block
153 */
154 static inline xfs_dir2_db_t
xfs_dir2_byte_to_db(struct xfs_da_geometry * geo,xfs_dir2_off_t by)155 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
156 {
157 return (xfs_dir2_db_t)(by >> geo->blklog);
158 }
159
160 /*
161 * Convert dataptr to a block number
162 */
163 static inline xfs_dir2_db_t
xfs_dir2_dataptr_to_db(struct xfs_da_geometry * geo,xfs_dir2_dataptr_t dp)164 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
165 {
166 return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
167 }
168
169 /*
170 * Convert byte in space to offset in a block
171 */
172 static inline xfs_dir2_data_aoff_t
xfs_dir2_byte_to_off(struct xfs_da_geometry * geo,xfs_dir2_off_t by)173 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
174 {
175 return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
176 }
177
178 /*
179 * Convert dataptr to a byte offset in a block
180 */
181 static inline xfs_dir2_data_aoff_t
xfs_dir2_dataptr_to_off(struct xfs_da_geometry * geo,xfs_dir2_dataptr_t dp)182 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
183 {
184 return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
185 }
186
187 /*
188 * Convert block and offset to byte in space
189 */
190 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)191 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
192 xfs_dir2_data_aoff_t o)
193 {
194 return ((xfs_dir2_off_t)db << geo->blklog) + o;
195 }
196
197 /*
198 * Convert block (DB) to block (dablk)
199 */
200 static inline xfs_dablk_t
xfs_dir2_db_to_da(struct xfs_da_geometry * geo,xfs_dir2_db_t db)201 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
202 {
203 return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
204 }
205
206 /*
207 * Convert byte in space to (DA) block
208 */
209 static inline xfs_dablk_t
xfs_dir2_byte_to_da(struct xfs_da_geometry * geo,xfs_dir2_off_t by)210 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
211 {
212 return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
213 }
214
215 /*
216 * Convert block and offset to dataptr
217 */
218 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)219 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
220 xfs_dir2_data_aoff_t o)
221 {
222 return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
223 }
224
225 /*
226 * Convert block (dablk) to block (DB)
227 */
228 static inline xfs_dir2_db_t
xfs_dir2_da_to_db(struct xfs_da_geometry * geo,xfs_dablk_t da)229 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
230 {
231 return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
232 }
233
234 /*
235 * Convert block (dablk) to byte offset in space
236 */
237 static inline xfs_dir2_off_t
xfs_dir2_da_to_byte(struct xfs_da_geometry * geo,xfs_dablk_t da)238 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
239 {
240 return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
241 }
242
243 /*
244 * Directory tail pointer accessor functions. Based on block geometry.
245 */
246 static inline struct xfs_dir2_block_tail *
xfs_dir2_block_tail_p(struct xfs_da_geometry * geo,struct xfs_dir2_data_hdr * hdr)247 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
248 {
249 return ((struct xfs_dir2_block_tail *)
250 ((char *)hdr + geo->blksize)) - 1;
251 }
252
253 static inline struct xfs_dir2_leaf_tail *
xfs_dir2_leaf_tail_p(struct xfs_da_geometry * geo,struct xfs_dir2_leaf * lp)254 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
255 {
256 return (struct xfs_dir2_leaf_tail *)
257 ((char *)lp + geo->blksize -
258 sizeof(struct xfs_dir2_leaf_tail));
259 }
260
261 /*
262 * The Linux API doesn't pass down the total size of the buffer
263 * we read into down to the filesystem. With the filldir concept
264 * it's not needed for correct information, but the XFS dir2 leaf
265 * code wants an estimate of the buffer size to calculate it's
266 * readahead window and size the buffers used for mapping to
267 * physical blocks.
268 *
269 * Try to give it an estimate that's good enough, maybe at some
270 * point we can change the ->readdir prototype to include the
271 * buffer size. For now we use the current glibc buffer size.
272 * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
273 */
274 #define XFS_READDIR_BUFSIZE (32768)
275
276 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
277 unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo,
278 struct xfs_dir2_data_hdr *hdr);
279 bool xfs_dir2_namecheck(const void *name, size_t length);
280
281 /*
282 * The "ascii-ci" feature was created to speed up case-insensitive lookups for
283 * a Samba product. Because of the inherent problems with CI and UTF-8
284 * encoding, etc, it was decided that Samba would be configured to export
285 * latin1/iso 8859-1 encodings as that covered >90% of the target markets for
286 * the product. Hence the "ascii-ci" casefolding code could be encoded into
287 * the XFS directory operations and remove all the overhead of casefolding from
288 * Samba.
289 *
290 * To provide consistent hashing behavior between the userspace and kernel,
291 * these functions prepare names for hashing by transforming specific bytes
292 * to other bytes. Robustness with other encodings is not guaranteed.
293 */
xfs_ascii_ci_need_xfrm(unsigned char c)294 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c)
295 {
296 if (c >= 0x41 && c <= 0x5a) /* A-Z */
297 return true;
298 if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */
299 return true;
300 if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */
301 return true;
302 return false;
303 }
304
xfs_ascii_ci_xfrm(unsigned char c)305 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c)
306 {
307 if (xfs_ascii_ci_need_xfrm(c))
308 c -= 'A' - 'a';
309 return c;
310 }
311
312 struct xfs_dir_update_params {
313 const struct xfs_inode *dp;
314 const struct xfs_inode *ip;
315 const struct xfs_name *name;
316 int delta;
317 };
318
319 #ifdef CONFIG_XFS_LIVE_HOOKS
320 void xfs_dir_update_hook(struct xfs_inode *dp, struct xfs_inode *ip,
321 int delta, const struct xfs_name *name);
322
323 struct xfs_dir_hook {
324 struct xfs_hook dirent_hook;
325 };
326
327 void xfs_dir_hook_disable(void);
328 void xfs_dir_hook_enable(void);
329
330 int xfs_dir_hook_add(struct xfs_mount *mp, struct xfs_dir_hook *hook);
331 void xfs_dir_hook_del(struct xfs_mount *mp, struct xfs_dir_hook *hook);
332 void xfs_dir_hook_setup(struct xfs_dir_hook *hook, notifier_fn_t mod_fn);
333 #else
334 # define xfs_dir_update_hook(dp, ip, delta, name) ((void)0)
335 #endif /* CONFIG_XFS_LIVE_HOOKS */
336
337 struct xfs_parent_args;
338
339 struct xfs_dir_update {
340 struct xfs_inode *dp;
341 const struct xfs_name *name;
342 struct xfs_inode *ip;
343 struct xfs_parent_args *ppargs;
344 };
345
346 int xfs_dir_create_child(struct xfs_trans *tp, unsigned int resblks,
347 struct xfs_dir_update *du);
348 int xfs_dir_add_child(struct xfs_trans *tp, unsigned int resblks,
349 struct xfs_dir_update *du);
350 int xfs_dir_remove_child(struct xfs_trans *tp, unsigned int resblks,
351 struct xfs_dir_update *du);
352
353 int xfs_dir_exchange_children(struct xfs_trans *tp, struct xfs_dir_update *du1,
354 struct xfs_dir_update *du2, unsigned int spaceres);
355 int xfs_dir_rename_children(struct xfs_trans *tp, struct xfs_dir_update *du_src,
356 struct xfs_dir_update *du_tgt, unsigned int spaceres,
357 struct xfs_dir_update *du_wip);
358
359 #endif /* __XFS_DIR2_H__ */
360