xref: /linux/fs/xfs/libxfs/xfs_dir2.h (revision 9e9f60108423f18a99c9cc93ef7f23490ecc709b)
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_DIR2_H__
19 #define __XFS_DIR2_H__
20 
21 struct xfs_bmap_free;
22 struct xfs_da_args;
23 struct xfs_inode;
24 struct xfs_mount;
25 struct xfs_trans;
26 struct xfs_dir2_sf_hdr;
27 struct xfs_dir2_sf_entry;
28 struct xfs_dir2_data_hdr;
29 struct xfs_dir2_data_entry;
30 struct xfs_dir2_data_unused;
31 
32 extern struct xfs_name	xfs_name_dotdot;
33 
34 /*
35  * directory filetype conversion tables.
36  */
37 #define S_SHIFT 12
38 extern const unsigned char xfs_mode_to_ftype[];
39 
40 /*
41  * directory operations vector for encode/decode routines
42  */
43 struct xfs_dir_ops {
44 	int	(*sf_entsize)(struct xfs_dir2_sf_hdr *hdr, int len);
45 	struct xfs_dir2_sf_entry *
46 		(*sf_nextentry)(struct xfs_dir2_sf_hdr *hdr,
47 				struct xfs_dir2_sf_entry *sfep);
48 	__uint8_t (*sf_get_ftype)(struct xfs_dir2_sf_entry *sfep);
49 	void	(*sf_put_ftype)(struct xfs_dir2_sf_entry *sfep,
50 				__uint8_t ftype);
51 	xfs_ino_t (*sf_get_ino)(struct xfs_dir2_sf_hdr *hdr,
52 				struct xfs_dir2_sf_entry *sfep);
53 	void	(*sf_put_ino)(struct xfs_dir2_sf_hdr *hdr,
54 			      struct xfs_dir2_sf_entry *sfep,
55 			      xfs_ino_t ino);
56 	xfs_ino_t (*sf_get_parent_ino)(struct xfs_dir2_sf_hdr *hdr);
57 	void	(*sf_put_parent_ino)(struct xfs_dir2_sf_hdr *hdr,
58 				     xfs_ino_t ino);
59 
60 	int	(*data_entsize)(int len);
61 	__uint8_t (*data_get_ftype)(struct xfs_dir2_data_entry *dep);
62 	void	(*data_put_ftype)(struct xfs_dir2_data_entry *dep,
63 				__uint8_t ftype);
64 	__be16 * (*data_entry_tag_p)(struct xfs_dir2_data_entry *dep);
65 	struct xfs_dir2_data_free *
66 		(*data_bestfree_p)(struct xfs_dir2_data_hdr *hdr);
67 
68 	xfs_dir2_data_aoff_t data_dot_offset;
69 	xfs_dir2_data_aoff_t data_dotdot_offset;
70 	xfs_dir2_data_aoff_t data_first_offset;
71 	size_t	data_entry_offset;
72 
73 	struct xfs_dir2_data_entry *
74 		(*data_dot_entry_p)(struct xfs_dir2_data_hdr *hdr);
75 	struct xfs_dir2_data_entry *
76 		(*data_dotdot_entry_p)(struct xfs_dir2_data_hdr *hdr);
77 	struct xfs_dir2_data_entry *
78 		(*data_first_entry_p)(struct xfs_dir2_data_hdr *hdr);
79 	struct xfs_dir2_data_entry *
80 		(*data_entry_p)(struct xfs_dir2_data_hdr *hdr);
81 	struct xfs_dir2_data_unused *
82 		(*data_unused_p)(struct xfs_dir2_data_hdr *hdr);
83 
84 	int	leaf_hdr_size;
85 	void	(*leaf_hdr_to_disk)(struct xfs_dir2_leaf *to,
86 				    struct xfs_dir3_icleaf_hdr *from);
87 	void	(*leaf_hdr_from_disk)(struct xfs_dir3_icleaf_hdr *to,
88 				      struct xfs_dir2_leaf *from);
89 	int	(*leaf_max_ents)(struct xfs_da_geometry *geo);
90 	struct xfs_dir2_leaf_entry *
91 		(*leaf_ents_p)(struct xfs_dir2_leaf *lp);
92 
93 	int	node_hdr_size;
94 	void	(*node_hdr_to_disk)(struct xfs_da_intnode *to,
95 				    struct xfs_da3_icnode_hdr *from);
96 	void	(*node_hdr_from_disk)(struct xfs_da3_icnode_hdr *to,
97 				      struct xfs_da_intnode *from);
98 	struct xfs_da_node_entry *
99 		(*node_tree_p)(struct xfs_da_intnode *dap);
100 
101 	int	free_hdr_size;
102 	void	(*free_hdr_to_disk)(struct xfs_dir2_free *to,
103 				    struct xfs_dir3_icfree_hdr *from);
104 	void	(*free_hdr_from_disk)(struct xfs_dir3_icfree_hdr *to,
105 				      struct xfs_dir2_free *from);
106 	int	(*free_max_bests)(struct xfs_da_geometry *geo);
107 	__be16 * (*free_bests_p)(struct xfs_dir2_free *free);
108 	xfs_dir2_db_t (*db_to_fdb)(struct xfs_da_geometry *geo,
109 				   xfs_dir2_db_t db);
110 	int	(*db_to_fdindex)(struct xfs_da_geometry *geo,
111 				 xfs_dir2_db_t db);
112 };
113 
114 extern const struct xfs_dir_ops *
115 	xfs_dir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
116 extern const struct xfs_dir_ops *
117 	xfs_nondir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
118 
119 /*
120  * Generic directory interface routines
121  */
122 extern void xfs_dir_startup(void);
123 extern int xfs_da_mount(struct xfs_mount *mp);
124 extern void xfs_da_unmount(struct xfs_mount *mp);
125 
126 extern int xfs_dir_isempty(struct xfs_inode *dp);
127 extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
128 				struct xfs_inode *pdp);
129 extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
130 				struct xfs_name *name, xfs_ino_t inum,
131 				xfs_fsblock_t *first,
132 				struct xfs_bmap_free *flist, xfs_extlen_t tot);
133 extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
134 				struct xfs_name *name, xfs_ino_t *inum,
135 				struct xfs_name *ci_name);
136 extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
137 				struct xfs_name *name, xfs_ino_t ino,
138 				xfs_fsblock_t *first,
139 				struct xfs_bmap_free *flist, xfs_extlen_t tot);
140 extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
141 				struct xfs_name *name, xfs_ino_t inum,
142 				xfs_fsblock_t *first,
143 				struct xfs_bmap_free *flist, xfs_extlen_t tot);
144 extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
145 				struct xfs_name *name);
146 
147 /*
148  * Direct call from the bmap code, bypassing the generic directory layer.
149  */
150 extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
151 
152 /*
153  * Interface routines used by userspace utilities
154  */
155 extern int xfs_dir2_isblock(struct xfs_da_args *args, int *r);
156 extern int xfs_dir2_isleaf(struct xfs_da_args *args, int *r);
157 extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
158 				struct xfs_buf *bp);
159 
160 extern void xfs_dir2_data_freescan(struct xfs_inode *dp,
161 		struct xfs_dir2_data_hdr *hdr, int *loghead);
162 extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
163 		struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
164 extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
165 		struct xfs_buf *bp);
166 extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
167 		struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
168 extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
169 		struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
170 		xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
171 extern void xfs_dir2_data_use_free(struct xfs_da_args *args,
172 		struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
173 		xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
174 		int *needlogp, int *needscanp);
175 
176 extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
177 		struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
178 		struct xfs_dir2_data_unused *dup);
179 
180 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
181 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
182 extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
183 extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
184 extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
185 
186 /*
187  * Directory offset/block conversion functions.
188  *
189  * DB blocks here are logical directory block numbers, not filesystem blocks.
190  */
191 
192 /*
193  * Convert dataptr to byte in file space
194  */
195 static inline xfs_dir2_off_t
196 xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
197 {
198 	return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
199 }
200 
201 /*
202  * Convert byte in file space to dataptr.  It had better be aligned.
203  */
204 static inline xfs_dir2_dataptr_t
205 xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
206 {
207 	return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
208 }
209 
210 /*
211  * Convert byte in space to (DB) block
212  */
213 static inline xfs_dir2_db_t
214 xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
215 {
216 	return (xfs_dir2_db_t)(by >> geo->blklog);
217 }
218 
219 /*
220  * Convert dataptr to a block number
221  */
222 static inline xfs_dir2_db_t
223 xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
224 {
225 	return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
226 }
227 
228 /*
229  * Convert byte in space to offset in a block
230  */
231 static inline xfs_dir2_data_aoff_t
232 xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
233 {
234 	return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
235 }
236 
237 /*
238  * Convert dataptr to a byte offset in a block
239  */
240 static inline xfs_dir2_data_aoff_t
241 xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
242 {
243 	return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
244 }
245 
246 /*
247  * Convert block and offset to byte in space
248  */
249 static inline xfs_dir2_off_t
250 xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
251 			xfs_dir2_data_aoff_t o)
252 {
253 	return ((xfs_dir2_off_t)db << geo->blklog) + o;
254 }
255 
256 /*
257  * Convert block (DB) to block (dablk)
258  */
259 static inline xfs_dablk_t
260 xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
261 {
262 	return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
263 }
264 
265 /*
266  * Convert byte in space to (DA) block
267  */
268 static inline xfs_dablk_t
269 xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
270 {
271 	return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
272 }
273 
274 /*
275  * Convert block and offset to dataptr
276  */
277 static inline xfs_dir2_dataptr_t
278 xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
279 			   xfs_dir2_data_aoff_t o)
280 {
281 	return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
282 }
283 
284 /*
285  * Convert block (dablk) to block (DB)
286  */
287 static inline xfs_dir2_db_t
288 xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
289 {
290 	return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
291 }
292 
293 /*
294  * Convert block (dablk) to byte offset in space
295  */
296 static inline xfs_dir2_off_t
297 xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
298 {
299 	return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
300 }
301 
302 /*
303  * Directory tail pointer accessor functions. Based on block geometry.
304  */
305 static inline struct xfs_dir2_block_tail *
306 xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
307 {
308 	return ((struct xfs_dir2_block_tail *)
309 		((char *)hdr + geo->blksize)) - 1;
310 }
311 
312 static inline struct xfs_dir2_leaf_tail *
313 xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
314 {
315 	return (struct xfs_dir2_leaf_tail *)
316 		((char *)lp + geo->blksize -
317 		  sizeof(struct xfs_dir2_leaf_tail));
318 }
319 
320 #endif	/* __XFS_DIR2_H__ */
321