2 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
3 * Copyright (c) 2013 Red Hat, Inc.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 #ifndef __XFS_DA_BTREE_H__
20 #define __XFS_DA_BTREE_H__
27 /*========================================================================
28 * Directory Structure when greater than XFS_LBSIZE(mp) bytes.
29 *========================================================================*/
32 * This structure is common to both leaf nodes and non-leaf nodes in the Btree.
34 * It is used to manage a doubly linked list of all blocks at the same
35 * level in the Btree, and to identify which type of block this is.
37 #define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */
38 #define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */
39 #define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */
40 #define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */
42 typedef struct xfs_da_blkinfo {
43 __be32 forw; /* previous block in list */
44 __be32 back; /* following block in list */
45 __be16 magic; /* validity check on block */
46 __be16 pad; /* unused */
50 * CRC enabled directory structure types
52 * The headers change size for the additional verification information, but
53 * otherwise the tree layouts and contents are unchanged. Hence the da btree
54 * code can use the struct xfs_da_blkinfo for manipulating the tree links and
55 * magic numbers without modification for both v2 and v3 nodes.
57 #define XFS_DA3_NODE_MAGIC 0x3ebe /* magic number: non-leaf blocks */
58 #define XFS_ATTR3_LEAF_MAGIC 0x3bee /* magic number: attribute leaf blks */
59 #define XFS_DIR3_LEAF1_MAGIC 0x3df1 /* magic number: v2 dirlf single blks */
60 #define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v2 dirlf multi blks */
62 struct xfs_da3_blkinfo {
64 * the node link manipulation code relies on the fact that the first
65 * element of this structure is the struct xfs_da_blkinfo so it can
66 * ignore the differences in the rest of the structures.
68 struct xfs_da_blkinfo hdr;
69 __be32 crc; /* CRC of block */
70 __be64 blkno; /* first block of the buffer */
71 __be64 lsn; /* sequence number of last write */
72 uuid_t uuid; /* filesystem we belong to */
73 __be64 owner; /* inode that owns the block */
77 * This is the structure of the root and intermediate nodes in the Btree.
78 * The leaf nodes are defined above.
80 * Entries are not packed.
82 * Since we have duplicate keys, use a binary search but always follow
83 * all match in the block, not just the first match found.
85 #define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */
87 typedef struct xfs_da_node_hdr {
88 struct xfs_da_blkinfo info; /* block type, links, etc. */
89 __be16 __count; /* count of active entries */
90 __be16 __level; /* level above leaves (leaf == 0) */
93 struct xfs_da3_node_hdr {
94 struct xfs_da3_blkinfo info; /* block type, links, etc. */
95 __be16 __count; /* count of active entries */
96 __be16 __level; /* level above leaves (leaf == 0) */
100 #define XFS_DA3_NODE_CRC_OFF (offsetof(struct xfs_da3_node_hdr, info.crc))
102 typedef struct xfs_da_node_entry {
103 __be32 hashval; /* hash value for this descendant */
104 __be32 before; /* Btree block before this key */
105 } xfs_da_node_entry_t;
107 typedef struct xfs_da_intnode {
108 struct xfs_da_node_hdr hdr;
109 struct xfs_da_node_entry __btree[];
112 struct xfs_da3_intnode {
113 struct xfs_da3_node_hdr hdr;
114 struct xfs_da_node_entry __btree[];
118 * In-core version of the node header to abstract the differences in the v2 and
119 * v3 disk format of the headers. Callers need to convert to/from disk format as
122 struct xfs_da3_icnode_hdr {
130 extern void xfs_da3_node_hdr_from_disk(struct xfs_da3_icnode_hdr *to,
131 struct xfs_da_intnode *from);
132 extern void xfs_da3_node_hdr_to_disk(struct xfs_da_intnode *to,
133 struct xfs_da3_icnode_hdr *from);
136 __xfs_da3_node_hdr_size(bool v3)
139 return sizeof(struct xfs_da3_node_hdr);
140 return sizeof(struct xfs_da_node_hdr);
143 xfs_da3_node_hdr_size(struct xfs_da_intnode *dap)
145 bool v3 = dap->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC);
147 return __xfs_da3_node_hdr_size(v3);
150 static inline struct xfs_da_node_entry *
151 xfs_da3_node_tree_p(struct xfs_da_intnode *dap)
153 if (dap->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC)) {
154 struct xfs_da3_intnode *dap3 = (struct xfs_da3_intnode *)dap;
155 return dap3->__btree;
160 extern void xfs_da3_intnode_from_disk(struct xfs_da3_icnode_hdr *to,
161 struct xfs_da_intnode *from);
162 extern void xfs_da3_intnode_to_disk(struct xfs_da_intnode *to,
163 struct xfs_da3_icnode_hdr *from);
165 #define XFS_LBSIZE(mp) (mp)->m_sb.sb_blocksize
167 /*========================================================================
168 * Btree searching and modification structure definitions.
169 *========================================================================*/
172 * Search comparison results
175 XFS_CMP_DIFFERENT, /* names are completely different */
176 XFS_CMP_EXACT, /* names are exactly the same */
177 XFS_CMP_CASE /* names are same but differ in case */
181 * Structure to ease passing around component names.
183 typedef struct xfs_da_args {
184 const __uint8_t *name; /* string (maybe not NULL terminated) */
185 int namelen; /* length of string (maybe no NULL) */
186 __uint8_t filetype; /* filetype of inode for directories */
187 __uint8_t *value; /* set of bytes (maybe contain NULLs) */
188 int valuelen; /* length of value */
189 int flags; /* argument flags (eg: ATTR_NOCREATE) */
190 xfs_dahash_t hashval; /* hash value of name */
191 xfs_ino_t inumber; /* input/output inode number */
192 struct xfs_inode *dp; /* directory inode to manipulate */
193 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */
194 struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */
195 struct xfs_trans *trans; /* current trans (changes over time) */
196 xfs_extlen_t total; /* total blocks needed, for 1st bmap */
197 int whichfork; /* data or attribute fork */
198 xfs_dablk_t blkno; /* blkno of attr leaf of interest */
199 int index; /* index of attr of interest in blk */
200 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
201 int rmtblkcnt; /* remote attr value block count */
202 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
203 int index2; /* index of 2nd attr in blk */
204 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
205 int rmtblkcnt2; /* remote attr value block count */
206 int op_flags; /* operation flags */
207 enum xfs_dacmp cmpresult; /* name compare result for lookups */
213 #define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */
214 #define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */
215 #define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */
216 #define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
217 #define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
219 #define XFS_DA_OP_FLAGS \
220 { XFS_DA_OP_JUSTCHECK, "JUSTCHECK" }, \
221 { XFS_DA_OP_RENAME, "RENAME" }, \
222 { XFS_DA_OP_ADDNAME, "ADDNAME" }, \
223 { XFS_DA_OP_OKNOENT, "OKNOENT" }, \
224 { XFS_DA_OP_CILOOKUP, "CILOOKUP" }
227 * Storage for holding state during Btree searches and split/join ops.
229 * Only need space for 5 intermediate nodes. With a minimum of 62-way
230 * fanout to the Btree, we can support over 900 million directory blocks,
231 * which is slightly more than enough.
233 typedef struct xfs_da_state_blk {
234 struct xfs_buf *bp; /* buffer containing block */
235 xfs_dablk_t blkno; /* filesystem blkno of buffer */
236 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
237 int index; /* relevant index into block */
238 xfs_dahash_t hashval; /* last hash value in block */
239 int magic; /* blk's magic number, ie: blk type */
240 } xfs_da_state_blk_t;
242 typedef struct xfs_da_state_path {
243 int active; /* number of active levels */
244 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
245 } xfs_da_state_path_t;
247 typedef struct xfs_da_state {
248 xfs_da_args_t *args; /* filename arguments */
249 struct xfs_mount *mp; /* filesystem mount point */
250 unsigned int blocksize; /* logical block size */
251 unsigned int node_ents; /* how many entries in danode */
252 xfs_da_state_path_t path; /* search/split paths */
253 xfs_da_state_path_t altpath; /* alternate path for join */
254 unsigned char inleaf; /* insert into 1->lf, 0->splf */
255 unsigned char extravalid; /* T/F: extrablk is in use */
256 unsigned char extraafter; /* T/F: extrablk is after new */
257 xfs_da_state_blk_t extrablk; /* for double-splits on leaves */
258 /* for dirv2 extrablk is data */
262 * Utility macros to aid in logging changed structure fields.
264 #define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE))
265 #define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
266 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
267 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
270 * Name ops for directory and/or attr name operations
273 xfs_dahash_t (*hashname)(struct xfs_name *);
274 enum xfs_dacmp (*compname)(struct xfs_da_args *,
275 const unsigned char *, int);
279 /*========================================================================
280 * Function prototypes.
281 *========================================================================*/
284 * Routines used for growing the Btree.
286 int xfs_da3_node_create(struct xfs_da_args *args, xfs_dablk_t blkno,
287 int level, struct xfs_buf **bpp, int whichfork);
288 int xfs_da3_split(xfs_da_state_t *state);
291 * Routines used for shrinking the Btree.
293 int xfs_da3_join(xfs_da_state_t *state);
294 void xfs_da3_fixhashpath(struct xfs_da_state *state,
295 struct xfs_da_state_path *path_to_to_fix);
298 * Routines used for finding things in the Btree.
300 int xfs_da3_node_lookup_int(xfs_da_state_t *state, int *result);
301 int xfs_da3_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
302 int forward, int release, int *result);
306 int xfs_da3_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
307 xfs_da_state_blk_t *new_blk);
308 int xfs_da3_node_read(struct xfs_trans *tp, struct xfs_inode *dp,
309 xfs_dablk_t bno, xfs_daddr_t mappedbno,
310 struct xfs_buf **bpp, int which_fork);
312 extern const struct xfs_buf_ops xfs_da3_node_buf_ops;
317 int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
318 int xfs_da_grow_inode_int(struct xfs_da_args *args, xfs_fileoff_t *bno,
320 int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
321 xfs_dablk_t bno, xfs_daddr_t mappedbno,
322 struct xfs_buf **bp, int whichfork);
323 int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
324 xfs_dablk_t bno, xfs_daddr_t mappedbno,
325 struct xfs_buf **bpp, int whichfork,
326 const struct xfs_buf_ops *ops);
327 xfs_daddr_t xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp,
328 xfs_dablk_t bno, xfs_daddr_t mapped_bno,
329 int whichfork, const struct xfs_buf_ops *ops);
330 int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
331 struct xfs_buf *dead_buf);
333 uint xfs_da_hashname(const __uint8_t *name_string, int name_length);
334 enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,
335 const unsigned char *name, int len);
338 xfs_da_state_t *xfs_da_state_alloc(void);
339 void xfs_da_state_free(xfs_da_state_t *state);
341 extern struct kmem_zone *xfs_da_state_zone;
342 extern const struct xfs_nameops xfs_default_nameops;
344 #endif /* __XFS_DA_BTREE_H__ */