blob: 3a9b9e809c602481ecd48264a4bcf4fe880e83be [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (c) 2000, 2002 Silicon Graphics, Inc. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of version 2 of the GNU General Public License as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it would be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11 *
12 * Further, this software is distributed without any warranty that it is
13 * free of the rightful claim of any third person regarding infringement
14 * or the like. Any license provided herein, whether implied or
15 * otherwise, applies only to this software file. Patent licenses, if
16 * any, provided herein do not apply to combinations of this program with
17 * other software, or any other product whatsoever.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write the Free Software Foundation, Inc., 59
21 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22 *
23 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24 * Mountain View, CA 94043, or:
25 *
26 * http://www.sgi.com
27 *
28 * For further information regarding this notice, see:
29 *
30 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31 */
32#ifndef __XFS_DA_BTREE_H__
33#define __XFS_DA_BTREE_H__
34
35struct xfs_buf;
36struct xfs_bmap_free;
37struct xfs_inode;
38struct xfs_mount;
39struct xfs_trans;
40struct zone;
41
42/*========================================================================
43 * Directory Structure when greater than XFS_LBSIZE(mp) bytes.
44 *========================================================================*/
45
46/*
47 * This structure is common to both leaf nodes and non-leaf nodes in the Btree.
48 *
49 * Is is used to manage a doubly linked list of all blocks at the same
50 * level in the Btree, and to identify which type of block this is.
51 */
52#define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */
53#define XFS_DIR_LEAF_MAGIC 0xfeeb /* magic number: directory leaf blks */
54#define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */
55#define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */
56#define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */
57
58#define XFS_DIRX_LEAF_MAGIC(mp) \
59 (XFS_DIR_IS_V1(mp) ? XFS_DIR_LEAF_MAGIC : XFS_DIR2_LEAFN_MAGIC)
60
61typedef struct xfs_da_blkinfo {
62 xfs_dablk_t forw; /* previous block in list */
63 xfs_dablk_t back; /* following block in list */
64 __uint16_t magic; /* validity check on block */
65 __uint16_t pad; /* unused */
66} xfs_da_blkinfo_t;
67
68/*
69 * This is the structure of the root and intermediate nodes in the Btree.
70 * The leaf nodes are defined above.
71 *
72 * Entries are not packed.
73 *
74 * Since we have duplicate keys, use a binary search but always follow
75 * all match in the block, not just the first match found.
76 */
77#define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */
78
79typedef struct xfs_da_intnode {
80 struct xfs_da_node_hdr { /* constant-structure header block */
81 xfs_da_blkinfo_t info; /* block type, links, etc. */
82 __uint16_t count; /* count of active entries */
83 __uint16_t level; /* level above leaves (leaf == 0) */
84 } hdr;
85 struct xfs_da_node_entry {
86 xfs_dahash_t hashval; /* hash value for this descendant */
87 xfs_dablk_t before; /* Btree block before this key */
88 } btree[1]; /* variable sized array of keys */
89} xfs_da_intnode_t;
90typedef struct xfs_da_node_hdr xfs_da_node_hdr_t;
91typedef struct xfs_da_node_entry xfs_da_node_entry_t;
92
93#define XFS_DA_MAXHASH ((xfs_dahash_t)-1) /* largest valid hash value */
94
95/*
96 * Macros used by directory code to interface to the filesystem.
97 */
98#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_LBSIZE)
99int xfs_lbsize(struct xfs_mount *mp);
100#define XFS_LBSIZE(mp) xfs_lbsize(mp)
101#else
102#define XFS_LBSIZE(mp) ((mp)->m_sb.sb_blocksize)
103#endif
104#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_LBLOG)
105int xfs_lblog(struct xfs_mount *mp);
106#define XFS_LBLOG(mp) xfs_lblog(mp)
107#else
108#define XFS_LBLOG(mp) ((mp)->m_sb.sb_blocklog)
109#endif
110
111/*
112 * Macros used by directory code to interface to the kernel
113 */
114
115/*
116 * Macros used to manipulate directory off_t's
117 */
118#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_MAKE_BNOENTRY)
119__uint32_t xfs_da_make_bnoentry(struct xfs_mount *mp, xfs_dablk_t bno,
120 int entry);
121#define XFS_DA_MAKE_BNOENTRY(mp,bno,entry) \
122 xfs_da_make_bnoentry(mp,bno,entry)
123#else
124#define XFS_DA_MAKE_BNOENTRY(mp,bno,entry) \
125 (((bno) << (mp)->m_dircook_elog) | (entry))
126#endif
127#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_MAKE_COOKIE)
128xfs_off_t xfs_da_make_cookie(struct xfs_mount *mp, xfs_dablk_t bno, int entry,
129 xfs_dahash_t hash);
130#define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash) \
131 xfs_da_make_cookie(mp,bno,entry,hash)
132#else
133#define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash) \
134 (((xfs_off_t)XFS_DA_MAKE_BNOENTRY(mp, bno, entry) << 32) | (hash))
135#endif
136#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_HASH)
137xfs_dahash_t xfs_da_cookie_hash(struct xfs_mount *mp, xfs_off_t cookie);
138#define XFS_DA_COOKIE_HASH(mp,cookie) xfs_da_cookie_hash(mp,cookie)
139#else
140#define XFS_DA_COOKIE_HASH(mp,cookie) ((xfs_dahash_t)(cookie))
141#endif
142#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_BNO)
143xfs_dablk_t xfs_da_cookie_bno(struct xfs_mount *mp, xfs_off_t cookie);
144#define XFS_DA_COOKIE_BNO(mp,cookie) xfs_da_cookie_bno(mp,cookie)
145#else
146#define XFS_DA_COOKIE_BNO(mp,cookie) \
147 (((xfs_off_t)(cookie) >> 31) == -1LL ? \
148 (xfs_dablk_t)0 : \
149 (xfs_dablk_t)((xfs_off_t)(cookie) >> ((mp)->m_dircook_elog + 32)))
150#endif
151#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_ENTRY)
152int xfs_da_cookie_entry(struct xfs_mount *mp, xfs_off_t cookie);
153#define XFS_DA_COOKIE_ENTRY(mp,cookie) xfs_da_cookie_entry(mp,cookie)
154#else
155#define XFS_DA_COOKIE_ENTRY(mp,cookie) \
156 (((xfs_off_t)(cookie) >> 31) == -1LL ? \
157 (xfs_dablk_t)0 : \
158 (xfs_dablk_t)(((xfs_off_t)(cookie) >> 32) & \
159 ((1 << (mp)->m_dircook_elog) - 1)))
160#endif
161
162
163/*========================================================================
164 * Btree searching and modification structure definitions.
165 *========================================================================*/
166
167/*
168 * Structure to ease passing around component names.
169 */
170typedef struct xfs_da_args {
171 uchar_t *name; /* string (maybe not NULL terminated) */
172 int namelen; /* length of string (maybe no NULL) */
173 uchar_t *value; /* set of bytes (maybe contain NULLs) */
174 int valuelen; /* length of value */
175 int flags; /* argument flags (eg: ATTR_NOCREATE) */
176 xfs_dahash_t hashval; /* hash value of name */
177 xfs_ino_t inumber; /* input/output inode number */
178 struct xfs_inode *dp; /* directory inode to manipulate */
179 xfs_fsblock_t *firstblock; /* ptr to firstblock for bmap calls */
180 struct xfs_bmap_free *flist; /* ptr to freelist for bmap_finish */
181 struct xfs_trans *trans; /* current trans (changes over time) */
182 xfs_extlen_t total; /* total blocks needed, for 1st bmap */
183 int whichfork; /* data or attribute fork */
184 xfs_dablk_t blkno; /* blkno of attr leaf of interest */
185 int index; /* index of attr of interest in blk */
186 xfs_dablk_t rmtblkno; /* remote attr value starting blkno */
187 int rmtblkcnt; /* remote attr value block count */
188 xfs_dablk_t blkno2; /* blkno of 2nd attr leaf of interest */
189 int index2; /* index of 2nd attr in blk */
190 xfs_dablk_t rmtblkno2; /* remote attr value starting blkno */
191 int rmtblkcnt2; /* remote attr value block count */
192 unsigned char justcheck; /* T/F: check for ok with no space */
193 unsigned char rename; /* T/F: this is an atomic rename op */
194 unsigned char addname; /* T/F: this is an add operation */
195 unsigned char oknoent; /* T/F: ok to return ENOENT, else die */
196} xfs_da_args_t;
197
198/*
199 * Structure to describe buffer(s) for a block.
200 * This is needed in the directory version 2 format case, when
201 * multiple non-contiguous fsblocks might be needed to cover one
202 * logical directory block.
203 * If the buffer count is 1 then the data pointer points to the
204 * same place as the b_addr field for the buffer, else to kmem_alloced memory.
205 */
206typedef struct xfs_dabuf {
207 int nbuf; /* number of buffer pointers present */
208 short dirty; /* data needs to be copied back */
209 short bbcount; /* how large is data in bbs */
210 void *data; /* pointer for buffers' data */
211#ifdef XFS_DABUF_DEBUG
212 inst_t *ra; /* return address of caller to make */
213 struct xfs_dabuf *next; /* next in global chain */
214 struct xfs_dabuf *prev; /* previous in global chain */
215 struct xfs_buftarg *target; /* device for buffer */
216 xfs_daddr_t blkno; /* daddr first in bps[0] */
217#endif
218 struct xfs_buf *bps[1]; /* actually nbuf of these */
219} xfs_dabuf_t;
220#define XFS_DA_BUF_SIZE(n) \
221 (sizeof(xfs_dabuf_t) + sizeof(struct xfs_buf *) * ((n) - 1))
222
223#ifdef XFS_DABUF_DEBUG
224extern xfs_dabuf_t *xfs_dabuf_global_list;
225#endif
226
227/*
228 * Storage for holding state during Btree searches and split/join ops.
229 *
230 * Only need space for 5 intermediate nodes. With a minimum of 62-way
231 * fanout to the Btree, we can support over 900 million directory blocks,
232 * which is slightly more than enough.
233 */
234typedef struct xfs_da_state_blk {
235 xfs_dabuf_t *bp; /* buffer containing block */
236 xfs_dablk_t blkno; /* filesystem blkno of buffer */
237 xfs_daddr_t disk_blkno; /* on-disk blkno (in BBs) of buffer */
238 int index; /* relevant index into block */
239 xfs_dahash_t hashval; /* last hash value in block */
240 int magic; /* blk's magic number, ie: blk type */
241} xfs_da_state_blk_t;
242
243typedef struct xfs_da_state_path {
244 int active; /* number of active levels */
245 xfs_da_state_blk_t blk[XFS_DA_NODE_MAXDEPTH];
246} xfs_da_state_path_t;
247
248typedef struct xfs_da_state {
249 xfs_da_args_t *args; /* filename arguments */
250 struct xfs_mount *mp; /* filesystem mount point */
251 unsigned int blocksize; /* logical block size */
252 unsigned int node_ents; /* how many entries in danode */
253 xfs_da_state_path_t path; /* search/split paths */
254 xfs_da_state_path_t altpath; /* alternate path for join */
255 unsigned char inleaf; /* insert into 1->lf, 0->splf */
256 unsigned char extravalid; /* T/F: extrablk is in use */
257 unsigned char extraafter; /* T/F: extrablk is after new */
258 xfs_da_state_blk_t extrablk; /* for double-splits on leafs */
259 /* for dirv2 extrablk is data */
260} xfs_da_state_t;
261
262/*
263 * Utility macros to aid in logging changed structure fields.
264 */
265#define XFS_DA_LOGOFF(BASE, ADDR) ((char *)(ADDR) - (char *)(BASE))
266#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE) \
267 (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
268 (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
269
270
271#ifdef __KERNEL__
272/*========================================================================
273 * Function prototypes for the kernel.
274 *========================================================================*/
275
276/*
277 * Routines used for growing the Btree.
278 */
279int xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
280 xfs_dabuf_t **bpp, int whichfork);
281int xfs_da_split(xfs_da_state_t *state);
282
283/*
284 * Routines used for shrinking the Btree.
285 */
286int xfs_da_join(xfs_da_state_t *state);
287void xfs_da_fixhashpath(xfs_da_state_t *state,
288 xfs_da_state_path_t *path_to_to_fix);
289
290/*
291 * Routines used for finding things in the Btree.
292 */
293int xfs_da_node_lookup_int(xfs_da_state_t *state, int *result);
294int xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
295 int forward, int release, int *result);
296/*
297 * Utility routines.
298 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299int xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
300 xfs_da_state_blk_t *new_blk);
301
302/*
303 * Utility routines.
304 */
305int xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
306int xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
307 xfs_dablk_t bno, xfs_daddr_t mappedbno,
308 xfs_dabuf_t **bp, int whichfork);
309int xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
310 xfs_dablk_t bno, xfs_daddr_t mappedbno,
311 xfs_dabuf_t **bpp, int whichfork);
312xfs_daddr_t xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp,
313 xfs_dablk_t bno, int whichfork);
314int xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
315 xfs_dabuf_t *dead_buf);
316
317uint xfs_da_hashname(uchar_t *name_string, int name_length);
318uint xfs_da_log2_roundup(uint i);
319xfs_da_state_t *xfs_da_state_alloc(void);
320void xfs_da_state_free(xfs_da_state_t *state);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321
322void xfs_da_buf_done(xfs_dabuf_t *dabuf);
323void xfs_da_log_buf(struct xfs_trans *tp, xfs_dabuf_t *dabuf, uint first,
324 uint last);
325void xfs_da_brelse(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
326void xfs_da_binval(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
327xfs_daddr_t xfs_da_blkno(xfs_dabuf_t *dabuf);
328
329extern struct kmem_zone *xfs_da_state_zone;
330#endif /* __KERNEL__ */
331
332#endif /* __XFS_DA_BTREE_H__ */