1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
4 * Copyright (c) 2013 Red Hat, Inc.
5 * All Rights Reserved.
6 */
7 #ifndef __XFS_DA_BTREE_H__
8 #define __XFS_DA_BTREE_H__
9
10 struct xfs_inode;
11 struct xfs_trans;
12
13 /*
14 * Directory/attribute geometry information. There will be one of these for each
15 * data fork type, and it will be passed around via the xfs_da_args. Global
16 * structures will be attached to the xfs_mount.
17 */
18 struct xfs_da_geometry {
19 unsigned int blksize; /* da block size in bytes */
20 unsigned int fsbcount; /* da block size in filesystem blocks */
21 uint8_t fsblog; /* log2 of _filesystem_ block size */
22 uint8_t blklog; /* log2 of da block size */
23 unsigned int node_hdr_size; /* danode header size in bytes */
24 unsigned int node_ents; /* # of entries in a danode */
25 unsigned int magicpct; /* 37% of block size in bytes */
26 xfs_dablk_t datablk; /* blockno of dir data v2 */
27 unsigned int leaf_hdr_size; /* dir2 leaf header size */
28 unsigned int leaf_max_ents; /* # of entries in dir2 leaf */
29 xfs_dablk_t leafblk; /* blockno of leaf data v2 */
30 unsigned int free_hdr_size; /* dir2 free header size */
31 unsigned int free_max_bests; /* # of bests entries in dir2 free */
32 xfs_dablk_t freeblk; /* blockno of free data v2 */
33 xfs_extnum_t max_extents; /* Max. extents in corresponding fork */
34
35 xfs_dir2_data_aoff_t data_first_offset;
36 size_t data_entry_offset;
37 };
38
39 /*========================================================================
40 * Btree searching and modification structure definitions.
41 *========================================================================*/
42
43 /*
44 * Search comparison results
45 */
46 enum xfs_dacmp {
47 XFS_CMP_DIFFERENT, /* names are completely different */
48 XFS_CMP_EXACT, /* names are exactly the same */
49 XFS_CMP_CASE /* names are same but differ in case */
50 };
51
52 /*
53 * Structure to ease passing around component names.
54 */
55 typedef struct xfs_da_args {
56 struct xfs_da_geometry *geo; /* da block geometry */
57 const uint8_t *name; /* string (maybe not NULL terminated) */
58 const uint8_t *new_name; /* new attr name */
59 void *value; /* set of bytes (maybe contain NULLs) */
60 void *new_value; /* new xattr value (may contain NULLs) */
61 struct xfs_inode *dp; /* directory inode to manipulate */
62 struct xfs_trans *trans; /* current trans (changes over time) */
63
64 xfs_ino_t inumber; /* input/output inode number */
65 xfs_ino_t owner; /* inode that owns the dir/attr data */
66
67 int valuelen; /* length of value */
68 int new_valuelen; /* length of new_value */
69 uint8_t filetype; /* filetype of inode for directories */
70 uint8_t op_flags; /* operation flags */
71 uint8_t attr_filter; /* XFS_ATTR_{ROOT,SECURE,INCOMPLETE} */
72 short namelen; /* length of string (maybe no NULL) */
73 short new_namelen; /* length of new attr name */
74 xfs_dahash_t hashval; /* hash value of name */
75 xfs_extlen_t total; /* total blocks needed, for 1st bmap */
76 int whichfork; /* data or attribute fork */
77 xfs_dablk_t blkno; /* blkno of attr leaf of interest */
78 int index; /* index of attr of interest in blk */
79 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
80 int rmtblkcnt; /* remote attr value block count */
81 int rmtvaluelen; /* remote attr value length in bytes */
82 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
83 int index2; /* index of 2nd attr in blk */
84 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
85 int rmtblkcnt2; /* remote attr value block count */
86 int rmtvaluelen2; /* remote attr value length in bytes */
87 enum xfs_dacmp cmpresult; /* name compare result for lookups */
88 } xfs_da_args_t;
89
90 /*
91 * Operation flags:
92 */
93 #define XFS_DA_OP_JUSTCHECK (1u << 0) /* check for ok with no space */
94 #define XFS_DA_OP_REPLACE (1u << 1) /* this is an atomic replace op */
95 #define XFS_DA_OP_ADDNAME (1u << 2) /* this is an add operation */
96 #define XFS_DA_OP_OKNOENT (1u << 3) /* lookup op, ENOENT ok, else die */
97 #define XFS_DA_OP_CILOOKUP (1u << 4) /* lookup returns CI name if found */
98 #define XFS_DA_OP_RECOVERY (1u << 5) /* Log recovery operation */
99 #define XFS_DA_OP_LOGGED (1u << 6) /* Use intent items to track op */
100
101 #define XFS_DA_OP_FLAGS \
102 { XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
103 { XFS_DA_OP_REPLACE, "REPLACE" }, \
104 { XFS_DA_OP_ADDNAME, "ADDNAME" }, \
105 { XFS_DA_OP_OKNOENT, "OKNOENT" }, \
106 { XFS_DA_OP_CILOOKUP, "CILOOKUP" }, \
107 { XFS_DA_OP_RECOVERY, "RECOVERY" }, \
108 { XFS_DA_OP_LOGGED, "LOGGED" }
109
110 /*
111 * Storage for holding state during Btree searches and split/join ops.
112 *
113 * Only need space for 5 intermediate nodes. With a minimum of 62-way
114 * fanout to the Btree, we can support over 900 million directory blocks,
115 * which is slightly more than enough.
116 */
117 typedef struct xfs_da_state_blk {
118 struct xfs_buf *bp; /* buffer containing block */
119 xfs_dablk_t blkno; /* filesystem blkno of buffer */
120 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
121 int index; /* relevant index into block */
122 xfs_dahash_t hashval; /* last hash value in block */
123 int magic; /* blk's magic number, ie: blk type */
124 } xfs_da_state_blk_t;
125
126 typedef struct xfs_da_state_path {
127 int active; /* number of active levels */
128 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
129 } xfs_da_state_path_t;
130
131 typedef struct xfs_da_state {
132 xfs_da_args_t *args; /* filename arguments */
133 struct xfs_mount *mp; /* filesystem mount point */
134 xfs_da_state_path_t path; /* search/split paths */
135 xfs_da_state_path_t altpath; /* alternate path for join */
136 unsigned char inleaf; /* insert into 1->lf, 0->splf */
137 unsigned char extravalid; /* T/F: extrablk is in use */
138 unsigned char extraafter; /* T/F: extrablk is after new */
139 xfs_da_state_blk_t extrablk; /* for double-splits on leaves */
140 /* for dirv2 extrablk is data */
141 } xfs_da_state_t;
142
143 /*
144 * In-core version of the node header to abstract the differences in the v2 and
145 * v3 disk format of the headers. Callers need to convert to/from disk format as
146 * appropriate.
147 */
148 struct xfs_da3_icnode_hdr {
149 uint32_t forw;
150 uint32_t back;
151 uint16_t magic;
152 uint16_t count;
153 uint16_t level;
154
155 /*
156 * Pointer to the on-disk format entries, which are behind the
157 * variable size (v4 vs v5) header in the on-disk block.
158 */
159 struct xfs_da_node_entry *btree;
160 };
161
162 /*
163 * Utility macros to aid in logging changed structure fields.
164 */
165 #define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE))
166 #define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
167 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
168 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
169
170 /*========================================================================
171 * Function prototypes.
172 *========================================================================*/
173
174 /*
175 * Routines used for growing the Btree.
176 */
177 int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno,
178 int level, struct xfs_buf **bpp, int whichfork);
179 int xfs_da3_split(xfs_da_state_t *state);
180
181 /*
182 * Routines used for shrinking the Btree.
183 */
184 int xfs_da3_join(xfs_da_state_t *state);
185 void xfs_da3_fixhashpath(struct xfs_da_state *state,
186 struct xfs_da_state_path *path_to_to_fix);
187
188 /*
189 * Routines used for finding things in the Btree.
190 */
191 int xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result);
192 int xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
193 int forward, int release, int *result);
194 /*
195 * Utility routines.
196 */
197 int xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
198 xfs_da_state_blk_t *new_blk);
199 int xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp,
200 xfs_dablk_t bno, struct xfs_buf **bpp, int whichfork);
201 int xfs_da3_node_read_mapped(struct xfs_trans *tp, struct xfs_inode *dp,
202 xfs_daddr_t mappedbno, struct xfs_buf **bpp,
203 int whichfork);
204
205 /*
206 * Utility routines.
207 */
208
209 #define XFS_DABUF_MAP_HOLE_OK (1u << 0)
210
211 int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
212 int xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno,
213 int count);
214 int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
215 xfs_dablk_t bno, struct xfs_buf **bp, int whichfork);
216 int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
217 xfs_dablk_t bno, unsigned int flags, struct xfs_buf **bpp,
218 int whichfork, const struct xfs_buf_ops *ops);
219 int xfs_da_reada_buf(struct xfs_inode *dp, xfs_dablk_t bno,
220 unsigned int flags, int whichfork,
221 const struct xfs_buf_ops *ops);
222 int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
223 struct xfs_buf *dead_buf);
224 void xfs_da_buf_copy(struct xfs_buf *dst, struct xfs_buf *src,
225 size_t size);
226
227 uint xfs_da_hashname(const uint8_t *name_string, int name_length);
228 enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,
229 const unsigned char *name, int len);
230
231
232 struct xfs_da_state *xfs_da_state_alloc(struct xfs_da_args *args);
233 void xfs_da_state_free(xfs_da_state_t *state);
234 void xfs_da_state_reset(struct xfs_da_state *state, struct xfs_da_args *args);
235
236 void xfs_da3_node_hdr_from_disk(struct xfs_mount *mp,
237 struct xfs_da3_icnode_hdr *to, struct xfs_da_intnode *from);
238 void xfs_da3_node_hdr_to_disk(struct xfs_mount *mp,
239 struct xfs_da_intnode *to, struct xfs_da3_icnode_hdr *from);
240 xfs_failaddr_t xfs_da3_header_check(struct xfs_buf *bp, xfs_ino_t owner);
241 xfs_failaddr_t xfs_da3_node_header_check(struct xfs_buf *bp, xfs_ino_t owner);
242
243 extern struct kmem_cache *xfs_da_state_cache;
244
245 #endif /* __XFS_DA_BTREE_H__ */
246
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.