Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
[pandora-kernel.git] / fs / xfs / xfs_ialloc_btree.c
1 /*
2  * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
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.
8  *
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.
13  *
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
17  */
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"
37
38
39 STATIC int
40 xfs_inobt_get_minrecs(
41         struct xfs_btree_cur    *cur,
42         int                     level)
43 {
44         return cur->bc_mp->m_inobt_mnr[level != 0];
45 }
46
47 STATIC struct xfs_btree_cur *
48 xfs_inobt_dup_cursor(
49         struct xfs_btree_cur    *cur)
50 {
51         return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
52                         cur->bc_private.a.agbp, cur->bc_private.a.agno);
53 }
54
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 */
60 {
61         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
62         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
63
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);
67 }
68
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)
76 {
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);
80
81         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
82
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;
91
92         error = xfs_alloc_vextent(&args);
93         if (error) {
94                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
95                 return error;
96         }
97         if (args.fsbno == NULLFSBLOCK) {
98                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
99                 *stat = 0;
100                 return 0;
101         }
102         ASSERT(args.len == 1);
103         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
104
105         new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
106         *stat = 1;
107         return 0;
108 }
109
110 STATIC int
111 xfs_inobt_free_block(
112         struct xfs_btree_cur    *cur,
113         struct xfs_buf          *bp)
114 {
115         xfs_fsblock_t           fsbno;
116         int                     error;
117
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;
122
123         xfs_trans_binval(cur->bc_tp, bp);
124         return error;
125 }
126
127 STATIC int
128 xfs_inobt_get_maxrecs(
129         struct xfs_btree_cur    *cur,
130         int                     level)
131 {
132         return cur->bc_mp->m_inobt_mxr[level != 0];
133 }
134
135 STATIC void
136 xfs_inobt_init_key_from_rec(
137         union xfs_btree_key     *key,
138         union xfs_btree_rec     *rec)
139 {
140         key->inobt.ir_startino = rec->inobt.ir_startino;
141 }
142
143 STATIC void
144 xfs_inobt_init_rec_from_key(
145         union xfs_btree_key     *key,
146         union xfs_btree_rec     *rec)
147 {
148         rec->inobt.ir_startino = key->inobt.ir_startino;
149 }
150
151 STATIC void
152 xfs_inobt_init_rec_from_cur(
153         struct xfs_btree_cur    *cur,
154         union xfs_btree_rec     *rec)
155 {
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);
159 }
160
161 /*
162  * initial value of ptr for lookup
163  */
164 STATIC void
165 xfs_inobt_init_ptr_from_cur(
166         struct xfs_btree_cur    *cur,
167         union xfs_btree_ptr     *ptr)
168 {
169         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
170
171         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
172
173         ptr->s = agi->agi_root;
174 }
175
176 STATIC __int64_t
177 xfs_inobt_key_diff(
178         struct xfs_btree_cur    *cur,
179         union xfs_btree_key     *key)
180 {
181         return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
182                           cur->bc_rec.i.ir_startino;
183 }
184
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)
191 {
192         return be32_to_cpu(k1->inobt.ir_startino) <
193                 be32_to_cpu(k2->inobt.ir_startino);
194 }
195
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)
201 {
202         return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
203                 be32_to_cpu(r2->inobt.ir_startino);
204 }
205 #endif  /* DEBUG */
206
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),
210
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
226 };
227
228 /*
229  * Allocate a new inode btree cursor.
230  */
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 */
237 {
238         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
239         struct xfs_btree_cur    *cur;
240
241         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
242
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;
248
249         cur->bc_ops = &xfs_inobt_ops;
250
251         cur->bc_private.a.agbp = agbp;
252         cur->bc_private.a.agno = agno;
253
254         return cur;
255 }
256
257 /*
258  * Calculate number of records in an inobt btree block.
259  */
260 int
261 xfs_inobt_maxrecs(
262         struct xfs_mount        *mp,
263         int                     blocklen,
264         int                     leaf)
265 {
266         blocklen -= XFS_INOBT_BLOCK_LEN(mp);
267
268         if (leaf)
269                 return blocklen / sizeof(xfs_inobt_rec_t);
270         return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));
271 }