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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 */
39#define XFS_DIR_LEAF_MAGIC 0xfeeb /* magic number: directory leaf blks */
40#define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */
41#define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */
42#define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */
43
44#define XFS_DIRX_LEAF_MAGIC(mp) \
45 (XFS_DIR_IS_V1(mp) ? XFS_DIR_LEAF_MAGIC : XFS_DIR2_LEAFN_MAGIC)
46
47typedef struct xfs_da_blkinfo {
Nathan Scott89da0542006-03-17 17:28:40 +110048 __be32 forw; /* previous block in list */
49 __be32 back; /* following block in list */
50 __be16 magic; /* validity check on block */
51 __be16 pad; /* unused */
Linus Torvalds1da177e2005-04-16 15:20:36 -070052} xfs_da_blkinfo_t;
53
54/*
55 * This is the structure of the root and intermediate nodes in the Btree.
56 * The leaf nodes are defined above.
57 *
58 * Entries are not packed.
59 *
60 * Since we have duplicate keys, use a binary search but always follow
61 * all match in the block, not just the first match found.
62 */
63#define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */
64
65typedef struct xfs_da_intnode {
66 struct xfs_da_node_hdr { /* constant-structure header block */
67 xfs_da_blkinfo_t info; /* block type, links, etc. */
68 __uint16_t count; /* count of active entries */
69 __uint16_t level; /* level above leaves (leaf == 0) */
70 } hdr;
71 struct xfs_da_node_entry {
Nathan Scott403432d2006-03-17 17:29:46 +110072 __be32 hashval; /* hash value for this descendant */
73 __be32 before; /* Btree block before this key */
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 } btree[1]; /* variable sized array of keys */
75} xfs_da_intnode_t;
76typedef struct xfs_da_node_hdr xfs_da_node_hdr_t;
77typedef struct xfs_da_node_entry xfs_da_node_entry_t;
78
79#define XFS_DA_MAXHASH ((xfs_dahash_t)-1) /* largest valid hash value */
80
Nathan Scotta844f452005-11-02 14:38:42 +110081#define XFS_LBSIZE(mp) (mp)->m_sb.sb_blocksize
82#define XFS_LBLOG(mp) (mp)->m_sb.sb_blocklog
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
Linus Torvalds1da177e2005-04-16 15:20:36 -070084#define XFS_DA_MAKE_BNOENTRY(mp,bno,entry) \
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 (((bno) << (mp)->m_dircook_elog) | (entry))
Linus Torvalds1da177e2005-04-16 15:20:36 -070086#define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash) \
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 (((xfs_off_t)XFS_DA_MAKE_BNOENTRY(mp, bno, entry) << 32) | (hash))
Nathan Scotta844f452005-11-02 14:38:42 +110088#define XFS_DA_COOKIE_HASH(mp,cookie) ((xfs_dahash_t)cookie)
89#define XFS_DA_COOKIE_BNO(mp,cookie) \
90 ((((xfs_off_t)(cookie) >> 31) == -1LL ? \
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 (xfs_dablk_t)0 : \
Nathan Scotta844f452005-11-02 14:38:42 +110092 (xfs_dablk_t)((xfs_off_t)(cookie) >> \
93 ((mp)->m_dircook_elog + 32))))
94#define XFS_DA_COOKIE_ENTRY(mp,cookie) \
95 ((((xfs_off_t)(cookie) >> 31) == -1LL ? \
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 (xfs_dablk_t)0 : \
97 (xfs_dablk_t)(((xfs_off_t)(cookie) >> 32) & \
Nathan Scotta844f452005-11-02 14:38:42 +110098 ((1 << (mp)->m_dircook_elog) - 1))))
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
100
101/*========================================================================
102 * Btree searching and modification structure definitions.
103 *========================================================================*/
104
105/*
106 * Structure to ease passing around component names.
107 */
108typedef struct xfs_da_args {
Nathan Scott80cce772005-11-02 11:43:04 +1100109 const uchar_t *name; /* string (maybe not NULL terminated) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 int namelen; /* length of string (maybe no NULL) */
111 uchar_t *value; /* set of bytes (maybe contain NULLs) */
112 int valuelen; /* length of value */
113 int flags; /* argument flags (eg: ATTR_NOCREATE) */
114 xfs_dahash_t hashval; /* hash value of name */
115 xfs_ino_t inumber; /* input/output inode number */
116 struct xfs_inode *dp; /* directory inode to manipulate */
117 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */
118 struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */
119 struct xfs_trans *trans; /* current trans (changes over time) */
120 xfs_extlen_t total; /* total blocks needed, for 1st bmap */
121 int whichfork; /* data or attribute fork */
122 xfs_dablk_t blkno; /* blkno of attr leaf of interest */
123 int index; /* index of attr of interest in blk */
124 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
125 int rmtblkcnt; /* remote attr value block count */
126 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
127 int index2; /* index of 2nd attr in blk */
128 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
129 int rmtblkcnt2; /* remote attr value block count */
130 unsigned char justcheck; /* T/F: check for ok with no space */
131 unsigned char rename; /* T/F: this is an atomic rename op */
132 unsigned char addname; /* T/F: this is an add operation */
133 unsigned char oknoent; /* T/F: ok to return ENOENT, else die */
134} xfs_da_args_t;
135
136/*
137 * Structure to describe buffer(s) for a block.
138 * This is needed in the directory version 2 format case, when
139 * multiple non-contiguous fsblocks might be needed to cover one
140 * logical directory block.
141 * If the buffer count is 1 then the data pointer points to the
142 * same place as the b_addr field for the buffer, else to kmem_alloced memory.
143 */
144typedef struct xfs_dabuf {
145 int nbuf; /* number of buffer pointers present */
146 short dirty; /* data needs to be copied back */
147 short bbcount; /* how large is data in bbs */
148 void *data; /* pointer for buffers' data */
149#ifdef XFS_DABUF_DEBUG
150 inst_t *ra; /* return address of caller to make */
151 struct xfs_dabuf *next; /* next in global chain */
152 struct xfs_dabuf *prev; /* previous in global chain */
153 struct xfs_buftarg *target; /* device for buffer */
154 xfs_daddr_t blkno; /* daddr first in bps[0] */
155#endif
156 struct xfs_buf *bps[1]; /* actually nbuf of these */
157} xfs_dabuf_t;
158#define XFS_DA_BUF_SIZE(n) \
159 (sizeof(xfs_dabuf_t) + sizeof(struct xfs_buf *) * ((n) - 1))
160
161#ifdef XFS_DABUF_DEBUG
162extern xfs_dabuf_t *xfs_dabuf_global_list;
163#endif
164
165/*
166 * Storage for holding state during Btree searches and split/join ops.
167 *
168 * Only need space for 5 intermediate nodes. With a minimum of 62-way
169 * fanout to the Btree, we can support over 900 million directory blocks,
170 * which is slightly more than enough.
171 */
172typedef struct xfs_da_state_blk {
173 xfs_dabuf_t *bp; /* buffer containing block */
174 xfs_dablk_t blkno; /* filesystem blkno of buffer */
175 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
176 int index; /* relevant index into block */
177 xfs_dahash_t hashval; /* last hash value in block */
178 int magic; /* blk's magic number, ie: blk type */
179} xfs_da_state_blk_t;
180
181typedef struct xfs_da_state_path {
182 int active; /* number of active levels */
183 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
184} xfs_da_state_path_t;
185
186typedef struct xfs_da_state {
187 xfs_da_args_t *args; /* filename arguments */
188 struct xfs_mount *mp; /* filesystem mount point */
189 unsigned int blocksize; /* logical block size */
190 unsigned int node_ents; /* how many entries in danode */
191 xfs_da_state_path_t path; /* search/split paths */
192 xfs_da_state_path_t altpath; /* alternate path for join */
193 unsigned char inleaf; /* insert into 1->lf, 0->splf */
194 unsigned char extravalid; /* T/F: extrablk is in use */
195 unsigned char extraafter; /* T/F: extrablk is after new */
196 xfs_da_state_blk_t extrablk; /* for double-splits on leafs */
197 /* for dirv2 extrablk is data */
198} xfs_da_state_t;
199
200/*
201 * Utility macros to aid in logging changed structure fields.
202 */
203#define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE))
204#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
205 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
206 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
207
208
209#ifdef __KERNEL__
210/*========================================================================
211 * Function prototypes for the kernel.
212 *========================================================================*/
213
214/*
215 * Routines used for growing the Btree.
216 */
217int xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
218 xfs_dabuf_t **bpp, int whichfork);
219int xfs_da_split(xfs_da_state_t *state);
220
221/*
222 * Routines used for shrinking the Btree.
223 */
224int xfs_da_join(xfs_da_state_t *state);
225void xfs_da_fixhashpath(xfs_da_state_t *state,
226 xfs_da_state_path_t *path_to_to_fix);
227
228/*
229 * Routines used for finding things in the Btree.
230 */
231int xfs_da_node_lookup_int(xfs_da_state_t *state, int *result);
232int xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
233 int forward, int release, int *result);
234/*
235 * Utility routines.
236 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237int xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
238 xfs_da_state_blk_t *new_blk);
239
240/*
241 * Utility routines.
242 */
243int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
244int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
245 xfs_dablk_t bno, xfs_daddr_t mappedbno,
246 xfs_dabuf_t **bp, int whichfork);
247int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
248 xfs_dablk_t bno, xfs_daddr_t mappedbno,
249 xfs_dabuf_t **bpp, int whichfork);
250xfs_daddr_t xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp,
251 xfs_dablk_t bno, int whichfork);
252int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
253 xfs_dabuf_t *dead_buf);
254
Nathan Scott80cce772005-11-02 11:43:04 +1100255uint xfs_da_hashname(const uchar_t *name_string, int name_length);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256uint xfs_da_log2_roundup(uint i);
257xfs_da_state_t *xfs_da_state_alloc(void);
258void xfs_da_state_free(xfs_da_state_t *state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259
260void xfs_da_buf_done(xfs_dabuf_t *dabuf);
261void xfs_da_log_buf(struct xfs_trans *tp, xfs_dabuf_t *dabuf, uint first,
262 uint last);
263void xfs_da_brelse(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
264void xfs_da_binval(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
265xfs_daddr_t xfs_da_blkno(xfs_dabuf_t *dabuf);
266
267extern struct kmem_zone *xfs_da_state_zone;
268#endif /* __KERNEL__ */
269
270#endif /* __XFS_DA_BTREE_H__ */