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, int *r);
65 extern int xfs_dir2_isleaf(struct xfs_da_args *args, int *r);
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 #endif	/* __XFS_DIR2_H__ */
252