[SCSI] mvsas: update comments
[linux-2.6/linux-mips.git] / fs / xfs / xfs_ialloc_btree.c
blobc6a75815aea05d666330111054b96b1587faf76d
1 /*
2 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * 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.
14 * 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
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_bmap_btree.h"
29 #include "xfs_alloc_btree.h"
30 #include "xfs_ialloc_btree.h"
31 #include "xfs_dinode.h"
32 #include "xfs_inode.h"
33 #include "xfs_btree.h"
34 #include "xfs_ialloc.h"
35 #include "xfs_alloc.h"
36 #include "xfs_error.h"
39 STATIC int
40 xfs_inobt_get_minrecs(
41 struct xfs_btree_cur *cur,
42 int level)
44 return cur->bc_mp->m_inobt_mnr[level != 0];
47 STATIC struct xfs_btree_cur *
48 xfs_inobt_dup_cursor(
49 struct xfs_btree_cur *cur)
51 return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
52 cur->bc_private.a.agbp, cur->bc_private.a.agno);
55 STATIC void
56 xfs_inobt_set_root(
57 struct xfs_btree_cur *cur,
58 union xfs_btree_ptr *nptr,
59 int inc) /* level change */
61 struct xfs_buf *agbp = cur->bc_private.a.agbp;
62 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
64 agi->agi_root = nptr->s;
65 be32_add_cpu(&agi->agi_level, inc);
66 xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT | XFS_AGI_LEVEL);
69 STATIC int
70 xfs_inobt_alloc_block(
71 struct xfs_btree_cur *cur,
72 union xfs_btree_ptr *start,
73 union xfs_btree_ptr *new,
74 int length,
75 int *stat)
77 xfs_alloc_arg_t args; /* block allocation args */
78 int error; /* error return value */
79 xfs_agblock_t sbno = be32_to_cpu(start->s);
81 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
83 memset(&args, 0, sizeof(args));
84 args.tp = cur->bc_tp;
85 args.mp = cur->bc_mp;
86 args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, sbno);
87 args.minlen = 1;
88 args.maxlen = 1;
89 args.prod = 1;
90 args.type = XFS_ALLOCTYPE_NEAR_BNO;
92 error = xfs_alloc_vextent(&args);
93 if (error) {
94 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
95 return error;
97 if (args.fsbno == NULLFSBLOCK) {
98 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
99 *stat = 0;
100 return 0;
102 ASSERT(args.len == 1);
103 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
105 new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
106 *stat = 1;
107 return 0;
110 STATIC int
111 xfs_inobt_free_block(
112 struct xfs_btree_cur *cur,
113 struct xfs_buf *bp)
115 xfs_fsblock_t fsbno;
116 int error;
118 fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp));
119 error = xfs_free_extent(cur->bc_tp, fsbno, 1);
120 if (error)
121 return error;
123 xfs_trans_binval(cur->bc_tp, bp);
124 return error;
127 STATIC int
128 xfs_inobt_get_maxrecs(
129 struct xfs_btree_cur *cur,
130 int level)
132 return cur->bc_mp->m_inobt_mxr[level != 0];
135 STATIC void
136 xfs_inobt_init_key_from_rec(
137 union xfs_btree_key *key,
138 union xfs_btree_rec *rec)
140 key->inobt.ir_startino = rec->inobt.ir_startino;
143 STATIC void
144 xfs_inobt_init_rec_from_key(
145 union xfs_btree_key *key,
146 union xfs_btree_rec *rec)
148 rec->inobt.ir_startino = key->inobt.ir_startino;
151 STATIC void
152 xfs_inobt_init_rec_from_cur(
153 struct xfs_btree_cur *cur,
154 union xfs_btree_rec *rec)
156 rec->inobt.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
157 rec->inobt.ir_freecount = cpu_to_be32(cur->bc_rec.i.ir_freecount);
158 rec->inobt.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
162 * initial value of ptr for lookup
164 STATIC void
165 xfs_inobt_init_ptr_from_cur(
166 struct xfs_btree_cur *cur,
167 union xfs_btree_ptr *ptr)
169 struct xfs_agi *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
171 ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
173 ptr->s = agi->agi_root;
176 STATIC __int64_t
177 xfs_inobt_key_diff(
178 struct xfs_btree_cur *cur,
179 union xfs_btree_key *key)
181 return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
182 cur->bc_rec.i.ir_startino;
185 #ifdef DEBUG
186 STATIC int
187 xfs_inobt_keys_inorder(
188 struct xfs_btree_cur *cur,
189 union xfs_btree_key *k1,
190 union xfs_btree_key *k2)
192 return be32_to_cpu(k1->inobt.ir_startino) <
193 be32_to_cpu(k2->inobt.ir_startino);
196 STATIC int
197 xfs_inobt_recs_inorder(
198 struct xfs_btree_cur *cur,
199 union xfs_btree_rec *r1,
200 union xfs_btree_rec *r2)
202 return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
203 be32_to_cpu(r2->inobt.ir_startino);
205 #endif /* DEBUG */
207 static const struct xfs_btree_ops xfs_inobt_ops = {
208 .rec_len = sizeof(xfs_inobt_rec_t),
209 .key_len = sizeof(xfs_inobt_key_t),
211 .dup_cursor = xfs_inobt_dup_cursor,
212 .set_root = xfs_inobt_set_root,
213 .alloc_block = xfs_inobt_alloc_block,
214 .free_block = xfs_inobt_free_block,
215 .get_minrecs = xfs_inobt_get_minrecs,
216 .get_maxrecs = xfs_inobt_get_maxrecs,
217 .init_key_from_rec = xfs_inobt_init_key_from_rec,
218 .init_rec_from_key = xfs_inobt_init_rec_from_key,
219 .init_rec_from_cur = xfs_inobt_init_rec_from_cur,
220 .init_ptr_from_cur = xfs_inobt_init_ptr_from_cur,
221 .key_diff = xfs_inobt_key_diff,
222 #ifdef DEBUG
223 .keys_inorder = xfs_inobt_keys_inorder,
224 .recs_inorder = xfs_inobt_recs_inorder,
225 #endif
229 * Allocate a new inode btree cursor.
231 struct xfs_btree_cur * /* new inode btree cursor */
232 xfs_inobt_init_cursor(
233 struct xfs_mount *mp, /* file system mount point */
234 struct xfs_trans *tp, /* transaction pointer */
235 struct xfs_buf *agbp, /* buffer for agi structure */
236 xfs_agnumber_t agno) /* allocation group number */
238 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
239 struct xfs_btree_cur *cur;
241 cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
243 cur->bc_tp = tp;
244 cur->bc_mp = mp;
245 cur->bc_nlevels = be32_to_cpu(agi->agi_level);
246 cur->bc_btnum = XFS_BTNUM_INO;
247 cur->bc_blocklog = mp->m_sb.sb_blocklog;
249 cur->bc_ops = &xfs_inobt_ops;
251 cur->bc_private.a.agbp = agbp;
252 cur->bc_private.a.agno = agno;
254 return cur;
258 * Calculate number of records in an inobt btree block.
261 xfs_inobt_maxrecs(
262 struct xfs_mount *mp,
263 int blocklen,
264 int leaf)
266 blocklen -= XFS_INOBT_BLOCK_LEN(mp);
268 if (leaf)
269 return blocklen / sizeof(xfs_inobt_rec_t);
270 return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));