xref: /openbmc/linux/fs/xfs/libxfs/xfs_dir2.h (revision ba61bb17)
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_defer_ops;
13 struct xfs_da_args;
14 struct xfs_inode;
15 struct xfs_mount;
16 struct xfs_trans;
17 struct xfs_dir2_sf_hdr;
18 struct xfs_dir2_sf_entry;
19 struct xfs_dir2_data_hdr;
20 struct xfs_dir2_data_entry;
21 struct xfs_dir2_data_unused;
22 
23 extern struct xfs_name	xfs_name_dotdot;
24 
25 /*
26  * Convert inode mode to directory entry filetype
27  */
28 extern unsigned char xfs_mode_to_ftype(int mode);
29 
30 /*
31  * directory operations vector for encode/decode routines
32  */
33 struct xfs_dir_ops {
34 	int	(*sf_entsize)(struct xfs_dir2_sf_hdr *hdr, int len);
35 	struct xfs_dir2_sf_entry *
36 		(*sf_nextentry)(struct xfs_dir2_sf_hdr *hdr,
37 				struct xfs_dir2_sf_entry *sfep);
38 	uint8_t (*sf_get_ftype)(struct xfs_dir2_sf_entry *sfep);
39 	void	(*sf_put_ftype)(struct xfs_dir2_sf_entry *sfep,
40 				uint8_t ftype);
41 	xfs_ino_t (*sf_get_ino)(struct xfs_dir2_sf_hdr *hdr,
42 				struct xfs_dir2_sf_entry *sfep);
43 	void	(*sf_put_ino)(struct xfs_dir2_sf_hdr *hdr,
44 			      struct xfs_dir2_sf_entry *sfep,
45 			      xfs_ino_t ino);
46 	xfs_ino_t (*sf_get_parent_ino)(struct xfs_dir2_sf_hdr *hdr);
47 	void	(*sf_put_parent_ino)(struct xfs_dir2_sf_hdr *hdr,
48 				     xfs_ino_t ino);
49 
50 	int	(*data_entsize)(int len);
51 	uint8_t (*data_get_ftype)(struct xfs_dir2_data_entry *dep);
52 	void	(*data_put_ftype)(struct xfs_dir2_data_entry *dep,
53 				uint8_t ftype);
54 	__be16 * (*data_entry_tag_p)(struct xfs_dir2_data_entry *dep);
55 	struct xfs_dir2_data_free *
56 		(*data_bestfree_p)(struct xfs_dir2_data_hdr *hdr);
57 
58 	xfs_dir2_data_aoff_t data_dot_offset;
59 	xfs_dir2_data_aoff_t data_dotdot_offset;
60 	xfs_dir2_data_aoff_t data_first_offset;
61 	size_t	data_entry_offset;
62 
63 	struct xfs_dir2_data_entry *
64 		(*data_dot_entry_p)(struct xfs_dir2_data_hdr *hdr);
65 	struct xfs_dir2_data_entry *
66 		(*data_dotdot_entry_p)(struct xfs_dir2_data_hdr *hdr);
67 	struct xfs_dir2_data_entry *
68 		(*data_first_entry_p)(struct xfs_dir2_data_hdr *hdr);
69 	struct xfs_dir2_data_entry *
70 		(*data_entry_p)(struct xfs_dir2_data_hdr *hdr);
71 	struct xfs_dir2_data_unused *
72 		(*data_unused_p)(struct xfs_dir2_data_hdr *hdr);
73 
74 	int	leaf_hdr_size;
75 	void	(*leaf_hdr_to_disk)(struct xfs_dir2_leaf *to,
76 				    struct xfs_dir3_icleaf_hdr *from);
77 	void	(*leaf_hdr_from_disk)(struct xfs_dir3_icleaf_hdr *to,
78 				      struct xfs_dir2_leaf *from);
79 	int	(*leaf_max_ents)(struct xfs_da_geometry *geo);
80 	struct xfs_dir2_leaf_entry *
81 		(*leaf_ents_p)(struct xfs_dir2_leaf *lp);
82 
83 	int	node_hdr_size;
84 	void	(*node_hdr_to_disk)(struct xfs_da_intnode *to,
85 				    struct xfs_da3_icnode_hdr *from);
86 	void	(*node_hdr_from_disk)(struct xfs_da3_icnode_hdr *to,
87 				      struct xfs_da_intnode *from);
88 	struct xfs_da_node_entry *
89 		(*node_tree_p)(struct xfs_da_intnode *dap);
90 
91 	int	free_hdr_size;
92 	void	(*free_hdr_to_disk)(struct xfs_dir2_free *to,
93 				    struct xfs_dir3_icfree_hdr *from);
94 	void	(*free_hdr_from_disk)(struct xfs_dir3_icfree_hdr *to,
95 				      struct xfs_dir2_free *from);
96 	int	(*free_max_bests)(struct xfs_da_geometry *geo);
97 	__be16 * (*free_bests_p)(struct xfs_dir2_free *free);
98 	xfs_dir2_db_t (*db_to_fdb)(struct xfs_da_geometry *geo,
99 				   xfs_dir2_db_t db);
100 	int	(*db_to_fdindex)(struct xfs_da_geometry *geo,
101 				 xfs_dir2_db_t db);
102 };
103 
104 extern const struct xfs_dir_ops *
105 	xfs_dir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
106 extern const struct xfs_dir_ops *
107 	xfs_nondir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
108 
109 /*
110  * Generic directory interface routines
111  */
112 extern void xfs_dir_startup(void);
113 extern int xfs_da_mount(struct xfs_mount *mp);
114 extern void xfs_da_unmount(struct xfs_mount *mp);
115 
116 extern int xfs_dir_isempty(struct xfs_inode *dp);
117 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
118 				struct xfs_inode *pdp);
119 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
120 				struct xfs_name *name, xfs_ino_t inum,
121 				xfs_fsblock_t *first,
122 				struct xfs_defer_ops *dfops, xfs_extlen_t tot);
123 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
124 				struct xfs_name *name, xfs_ino_t *inum,
125 				struct xfs_name *ci_name);
126 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
127 				struct xfs_name *name, xfs_ino_t ino,
128 				xfs_fsblock_t *first,
129 				struct xfs_defer_ops *dfops, xfs_extlen_t tot);
130 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
131 				struct xfs_name *name, xfs_ino_t inum,
132 				xfs_fsblock_t *first,
133 				struct xfs_defer_ops *dfops, xfs_extlen_t tot);
134 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
135 				struct xfs_name *name);
136 
137 /*
138  * Direct call from the bmap code, bypassing the generic directory layer.
139  */
140 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
141 
142 /*
143  * Interface routines used by userspace utilities
144  */
145 extern int xfs_dir2_isblock(struct xfs_da_args *args, int *r);
146 extern int xfs_dir2_isleaf(struct xfs_da_args *args, int *r);
147 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
148 				struct xfs_buf *bp);
149 
150 extern void xfs_dir2_data_freescan_int(struct xfs_da_geometry *geo,
151 		const struct xfs_dir_ops *ops,
152 		struct xfs_dir2_data_hdr *hdr, int *loghead);
153 extern void xfs_dir2_data_freescan(struct xfs_inode *dp,
154 		struct xfs_dir2_data_hdr *hdr, int *loghead);
155 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
156 		struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
157 extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
158 		struct xfs_buf *bp);
159 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
160 		struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
161 extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
162 		struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
163 		xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
164 extern int xfs_dir2_data_use_free(struct xfs_da_args *args,
165 		struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
166 		xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
167 		int *needlogp, int *needscanp);
168 
169 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
170 		struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
171 		struct xfs_dir2_data_unused *dup);
172 
173 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
174 
175 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
176 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
177 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
178 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
179 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
180 
181 /*
182  * Directory offset/block conversion functions.
183  *
184  * DB blocks here are logical directory block numbers, not filesystem blocks.
185  */
186 
187 /*
188  * Convert dataptr to byte in file space
189  */
190 static inline xfs_dir2_off_t
191 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
192 {
193 	return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
194 }
195 
196 /*
197  * Convert byte in file space to dataptr.  It had better be aligned.
198  */
199 static inline xfs_dir2_dataptr_t
200 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
201 {
202 	return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
203 }
204 
205 /*
206  * Convert byte in space to (DB) block
207  */
208 static inline xfs_dir2_db_t
209 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
210 {
211 	return (xfs_dir2_db_t)(by >> geo->blklog);
212 }
213 
214 /*
215  * Convert dataptr to a block number
216  */
217 static inline xfs_dir2_db_t
218 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
219 {
220 	return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
221 }
222 
223 /*
224  * Convert byte in space to offset in a block
225  */
226 static inline xfs_dir2_data_aoff_t
227 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
228 {
229 	return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
230 }
231 
232 /*
233  * Convert dataptr to a byte offset in a block
234  */
235 static inline xfs_dir2_data_aoff_t
236 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
237 {
238 	return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
239 }
240 
241 /*
242  * Convert block and offset to byte in space
243  */
244 static inline xfs_dir2_off_t
245 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
246 			xfs_dir2_data_aoff_t o)
247 {
248 	return ((xfs_dir2_off_t)db << geo->blklog) + o;
249 }
250 
251 /*
252  * Convert block (DB) to block (dablk)
253  */
254 static inline xfs_dablk_t
255 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
256 {
257 	return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
258 }
259 
260 /*
261  * Convert byte in space to (DA) block
262  */
263 static inline xfs_dablk_t
264 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
265 {
266 	return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
267 }
268 
269 /*
270  * Convert block and offset to dataptr
271  */
272 static inline xfs_dir2_dataptr_t
273 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
274 			   xfs_dir2_data_aoff_t o)
275 {
276 	return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
277 }
278 
279 /*
280  * Convert block (dablk) to block (DB)
281  */
282 static inline xfs_dir2_db_t
283 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
284 {
285 	return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
286 }
287 
288 /*
289  * Convert block (dablk) to byte offset in space
290  */
291 static inline xfs_dir2_off_t
292 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
293 {
294 	return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
295 }
296 
297 /*
298  * Directory tail pointer accessor functions. Based on block geometry.
299  */
300 static inline struct xfs_dir2_block_tail *
301 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
302 {
303 	return ((struct xfs_dir2_block_tail *)
304 		((char *)hdr + geo->blksize)) - 1;
305 }
306 
307 static inline struct xfs_dir2_leaf_tail *
308 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
309 {
310 	return (struct xfs_dir2_leaf_tail *)
311 		((char *)lp + geo->blksize -
312 		  sizeof(struct xfs_dir2_leaf_tail));
313 }
314 
315 /*
316  * The Linux API doesn't pass down the total size of the buffer
317  * we read into down to the filesystem.  With the filldir concept
318  * it's not needed for correct information, but the XFS dir2 leaf
319  * code wants an estimate of the buffer size to calculate it's
320  * readahead window and size the buffers used for mapping to
321  * physical blocks.
322  *
323  * Try to give it an estimate that's good enough, maybe at some
324  * point we can change the ->readdir prototype to include the
325  * buffer size.  For now we use the current glibc buffer size.
326  * musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
327  */
328 #define XFS_READDIR_BUFSIZE	(32768)
329 
330 unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
331 void *xfs_dir3_data_endp(struct xfs_da_geometry *geo,
332 		struct xfs_dir2_data_hdr *hdr);
333 
334 #endif	/* __XFS_DIR2_H__ */
335