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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Nathan Scott7b718762005-11-02 14:58:39 +11002 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
Nathan Scott7b718762005-11-02 14:58:39 +11005 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * published by the Free Software Foundation.
8 *
Nathan Scott7b718762005-11-02 14:58:39 +11009 * 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 *
Nathan Scott7b718762005-11-02 14:58:39 +110014 * 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 */
18#ifndef __XFS_DA_BTREE_H__
19#define __XFS_DA_BTREE_H__
20
21struct xfs_buf;
22struct xfs_bmap_free;
23struct xfs_inode;
24struct xfs_mount;
25struct xfs_trans;
26struct zone;
27
28/*========================================================================
29 * Directory Structure when greater than XFS_LBSIZE(mp) bytes.
30 *========================================================================*/
31
32/*
33 * This structure is common to both leaf nodes and non-leaf nodes in the Btree.
34 *
35 * Is is used to manage a doubly linked list of all blocks at the same
36 * level in the Btree, and to identify which type of block this is.
37 */
38#define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */
40#define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */
41#define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043typedef struct xfs_da_blkinfo {
Nathan Scott89da0542006-03-17 17:28:40 +110044 __be32 forw; /* previous block in list */
45 __be32 back; /* following block in list */
46 __be16 magic; /* validity check on block */
47 __be16 pad; /* unused */
Linus Torvalds1da177e2005-04-16 15:20:36 -070048} xfs_da_blkinfo_t;
49
50/*
51 * This is the structure of the root and intermediate nodes in the Btree.
52 * The leaf nodes are defined above.
53 *
54 * Entries are not packed.
55 *
56 * Since we have duplicate keys, use a binary search but always follow
57 * all match in the block, not just the first match found.
58 */
59#define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */
60
61typedef struct xfs_da_intnode {
62 struct xfs_da_node_hdr { /* constant-structure header block */
63 xfs_da_blkinfo_t info; /* block type, links, etc. */
Nathan Scottfac80cc2006-03-17 17:29:56 +110064 __be16 count; /* count of active entries */
65 __be16 level; /* level above leaves (leaf == 0) */
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 } hdr;
67 struct xfs_da_node_entry {
Nathan Scott403432d2006-03-17 17:29:46 +110068 __be32 hashval; /* hash value for this descendant */
69 __be32 before; /* Btree block before this key */
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 } btree[1]; /* variable sized array of keys */
71} xfs_da_intnode_t;
72typedef struct xfs_da_node_hdr xfs_da_node_hdr_t;
73typedef struct xfs_da_node_entry xfs_da_node_entry_t;
74
Nathan Scotta844f452005-11-02 14:38:42 +110075#define XFS_LBSIZE(mp) (mp)->m_sb.sb_blocksize
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
77/*========================================================================
78 * Btree searching and modification structure definitions.
79 *========================================================================*/
80
81/*
Barry Naujok5163f952008-05-21 16:41:01 +100082 * Search comparison results
83 */
84enum xfs_dacmp {
85 XFS_CMP_DIFFERENT, /* names are completely different */
86 XFS_CMP_EXACT, /* names are exactly the same */
87 XFS_CMP_CASE /* names are same but differ in case */
88};
89
90/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 * Structure to ease passing around component names.
92 */
93typedef struct xfs_da_args {
Christoph Hellwiga5687782009-02-09 08:37:39 +010094 const __uint8_t *name; /* string (maybe not NULL terminated) */
Linus Torvalds1da177e2005-04-16 15:20:36 -070095 int namelen; /* length of string (maybe no NULL) */
Christoph Hellwiga5687782009-02-09 08:37:39 +010096 __uint8_t *value; /* set of bytes (maybe contain NULLs) */
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 int valuelen; /* length of value */
98 int flags; /* argument flags (eg: ATTR_NOCREATE) */
99 xfs_dahash_t hashval; /* hash value of name */
100 xfs_ino_t inumber; /* input/output inode number */
101 struct xfs_inode *dp; /* directory inode to manipulate */
102 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */
103 struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */
104 struct xfs_trans *trans; /* current trans (changes over time) */
105 xfs_extlen_t total; /* total blocks needed, for 1st bmap */
106 int whichfork; /* data or attribute fork */
107 xfs_dablk_t blkno; /* blkno of attr leaf of interest */
108 int index; /* index of attr of interest in blk */
109 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
110 int rmtblkcnt; /* remote attr value block count */
111 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
112 int index2; /* index of 2nd attr in blk */
113 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
114 int rmtblkcnt2; /* remote attr value block count */
Barry Naujok6a178102008-05-21 16:42:05 +1000115 int op_flags; /* operation flags */
Barry Naujok5163f952008-05-21 16:41:01 +1000116 enum xfs_dacmp cmpresult; /* name compare result for lookups */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117} xfs_da_args_t;
118
119/*
Barry Naujok6a178102008-05-21 16:42:05 +1000120 * Operation flags:
121 */
122#define XFS_DA_OP_JUSTCHECK 0x0001 /* check for ok with no space */
123#define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */
124#define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */
125#define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
Barry Naujok384f3ce2008-05-21 16:58:22 +1000126#define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
Barry Naujok6a178102008-05-21 16:42:05 +1000127
128/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 * Structure to describe buffer(s) for a block.
130 * This is needed in the directory version 2 format case, when
131 * multiple non-contiguous fsblocks might be needed to cover one
132 * logical directory block.
133 * If the buffer count is 1 then the data pointer points to the
134 * same place as the b_addr field for the buffer, else to kmem_alloced memory.
135 */
136typedef struct xfs_dabuf {
137 int nbuf; /* number of buffer pointers present */
138 short dirty; /* data needs to be copied back */
139 short bbcount; /* how large is data in bbs */
140 void *data; /* pointer for buffers' data */
141#ifdef XFS_DABUF_DEBUG
142 inst_t *ra; /* return address of caller to make */
143 struct xfs_dabuf *next; /* next in global chain */
144 struct xfs_dabuf *prev; /* previous in global chain */
145 struct xfs_buftarg *target; /* device for buffer */
146 xfs_daddr_t blkno; /* daddr first in bps[0] */
147#endif
148 struct xfs_buf *bps[1]; /* actually nbuf of these */
149} xfs_dabuf_t;
150#define XFS_DA_BUF_SIZE(n) \
151 (sizeof(xfs_dabuf_t) + sizeof(struct xfs_buf *) * ((n) - 1))
152
153#ifdef XFS_DABUF_DEBUG
154extern xfs_dabuf_t *xfs_dabuf_global_list;
155#endif
156
157/*
158 * Storage for holding state during Btree searches and split/join ops.
159 *
160 * Only need space for 5 intermediate nodes. With a minimum of 62-way
161 * fanout to the Btree, we can support over 900 million directory blocks,
162 * which is slightly more than enough.
163 */
164typedef struct xfs_da_state_blk {
165 xfs_dabuf_t *bp; /* buffer containing block */
166 xfs_dablk_t blkno; /* filesystem blkno of buffer */
167 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
168 int index; /* relevant index into block */
169 xfs_dahash_t hashval; /* last hash value in block */
170 int magic; /* blk's magic number, ie: blk type */
171} xfs_da_state_blk_t;
172
173typedef struct xfs_da_state_path {
174 int active; /* number of active levels */
175 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
176} xfs_da_state_path_t;
177
178typedef struct xfs_da_state {
179 xfs_da_args_t *args; /* filename arguments */
180 struct xfs_mount *mp; /* filesystem mount point */
181 unsigned int blocksize; /* logical block size */
182 unsigned int node_ents; /* how many entries in danode */
183 xfs_da_state_path_t path; /* search/split paths */
184 xfs_da_state_path_t altpath; /* alternate path for join */
185 unsigned char inleaf; /* insert into 1->lf, 0->splf */
186 unsigned char extravalid; /* T/F: extrablk is in use */
187 unsigned char extraafter; /* T/F: extrablk is after new */
188 xfs_da_state_blk_t extrablk; /* for double-splits on leafs */
189 /* for dirv2 extrablk is data */
190} xfs_da_state_t;
191
192/*
193 * Utility macros to aid in logging changed structure fields.
194 */
195#define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE))
196#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
197 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
198 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
199
Barry Naujok5163f952008-05-21 16:41:01 +1000200/*
201 * Name ops for directory and/or attr name operations
202 */
203struct xfs_nameops {
204 xfs_dahash_t (*hashname)(struct xfs_name *);
205 enum xfs_dacmp (*compname)(struct xfs_da_args *, const char *, int);
206};
207
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209/*========================================================================
Barry Naujok847fff52008-10-30 17:05:38 +1100210 * Function prototypes.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 *========================================================================*/
212
213/*
214 * Routines used for growing the Btree.
215 */
216int xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
217 xfs_dabuf_t **bpp, int whichfork);
218int xfs_da_split(xfs_da_state_t *state);
219
220/*
221 * Routines used for shrinking the Btree.
222 */
223int xfs_da_join(xfs_da_state_t *state);
224void xfs_da_fixhashpath(xfs_da_state_t *state,
225 xfs_da_state_path_t *path_to_to_fix);
226
227/*
228 * Routines used for finding things in the Btree.
229 */
230int xfs_da_node_lookup_int(xfs_da_state_t *state, int *result);
231int xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
232 int forward, int release, int *result);
233/*
234 * Utility routines.
235 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236int xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
237 xfs_da_state_blk_t *new_blk);
238
239/*
240 * Utility routines.
241 */
242int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
243int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
244 xfs_dablk_t bno, xfs_daddr_t mappedbno,
245 xfs_dabuf_t **bp, int whichfork);
246int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
247 xfs_dablk_t bno, xfs_daddr_t mappedbno,
248 xfs_dabuf_t **bpp, int whichfork);
249xfs_daddr_t xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp,
250 xfs_dablk_t bno, int whichfork);
251int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
252 xfs_dabuf_t *dead_buf);
253
Christoph Hellwiga5687782009-02-09 08:37:39 +0100254uint xfs_da_hashname(const __uint8_t *name_string, int name_length);
Barry Naujok5163f952008-05-21 16:41:01 +1000255enum xfs_dacmp xfs_da_compname(struct xfs_da_args *args,
256 const char *name, int len);
257
258
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259xfs_da_state_t *xfs_da_state_alloc(void);
260void xfs_da_state_free(xfs_da_state_t *state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261
262void xfs_da_buf_done(xfs_dabuf_t *dabuf);
263void xfs_da_log_buf(struct xfs_trans *tp, xfs_dabuf_t *dabuf, uint first,
264 uint last);
265void xfs_da_brelse(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
266void xfs_da_binval(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
267xfs_daddr_t xfs_da_blkno(xfs_dabuf_t *dabuf);
268
269extern struct kmem_zone *xfs_da_state_zone;
David Chinnera8272ce2007-11-23 16:28:09 +1100270extern struct kmem_zone *xfs_dabuf_zone;
Hannes Eder24418492009-03-04 19:33:48 +0100271extern const struct xfs_nameops xfs_default_nameops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272
273#endif /* __XFS_DA_BTREE_H__ */