xfs: correctly decrement the extent buffer index in xfs_bmap_del_extent
[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_btree_trace.h"
35 #include "xfs_ialloc.h"
36 #include "xfs_alloc.h"
37 #include "xfs_error.h"
38
39
40 STATIC int
41 xfs_inobt_get_minrecs(
42         struct xfs_btree_cur    *cur,
43         int                     level)
44 {
45         return cur->bc_mp->m_inobt_mnr[level != 0];
46 }
47
48 STATIC struct xfs_btree_cur *
49 xfs_inobt_dup_cursor(
50         struct xfs_btree_cur    *cur)
51 {
52         return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
53                         cur->bc_private.a.agbp, cur->bc_private.a.agno);
54 }
55
56 STATIC void
57 xfs_inobt_set_root(
58         struct xfs_btree_cur    *cur,
59         union xfs_btree_ptr     *nptr,
60         int                     inc)    /* level change */
61 {
62         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
63         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
64
65         agi->agi_root = nptr->s;
66         be32_add_cpu(&agi->agi_level, inc);
67         xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT | XFS_AGI_LEVEL);
68 }
69
70 STATIC int
71 xfs_inobt_alloc_block(
72         struct xfs_btree_cur    *cur,
73         union xfs_btree_ptr     *start,
74         union xfs_btree_ptr     *new,
75         int                     length,
76         int                     *stat)
77 {
78         xfs_alloc_arg_t         args;           /* block allocation args */
79         int                     error;          /* error return value */
80         xfs_agblock_t           sbno = be32_to_cpu(start->s);
81
82         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
83
84         memset(&args, 0, sizeof(args));
85         args.tp = cur->bc_tp;
86         args.mp = cur->bc_mp;
87         args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, sbno);
88         args.minlen = 1;
89         args.maxlen = 1;
90         args.prod = 1;
91         args.type = XFS_ALLOCTYPE_NEAR_BNO;
92
93         error = xfs_alloc_vextent(&args);
94         if (error) {
95                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
96                 return error;
97         }
98         if (args.fsbno == NULLFSBLOCK) {
99                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
100                 *stat = 0;
101                 return 0;
102         }
103         ASSERT(args.len == 1);
104         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
105
106         new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
107         *stat = 1;
108         return 0;
109 }
110
111 STATIC int
112 xfs_inobt_free_block(
113         struct xfs_btree_cur    *cur,
114         struct xfs_buf          *bp)
115 {
116         xfs_fsblock_t           fsbno;
117         int                     error;
118
119         fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp));
120         error = xfs_free_extent(cur->bc_tp, fsbno, 1);
121         if (error)
122                 return error;
123
124         xfs_trans_binval(cur->bc_tp, bp);
125         return error;
126 }
127
128 STATIC int
129 xfs_inobt_get_maxrecs(
130         struct xfs_btree_cur    *cur,
131         int                     level)
132 {
133         return cur->bc_mp->m_inobt_mxr[level != 0];
134 }
135
136 STATIC void
137 xfs_inobt_init_key_from_rec(
138         union xfs_btree_key     *key,
139         union xfs_btree_rec     *rec)
140 {
141         key->inobt.ir_startino = rec->inobt.ir_startino;
142 }
143
144 STATIC void
145 xfs_inobt_init_rec_from_key(
146         union xfs_btree_key     *key,
147         union xfs_btree_rec     *rec)
148 {
149         rec->inobt.ir_startino = key->inobt.ir_startino;
150 }
151
152 STATIC void
153 xfs_inobt_init_rec_from_cur(
154         struct xfs_btree_cur    *cur,
155         union xfs_btree_rec     *rec)
156 {
157         rec->inobt.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
158         rec->inobt.ir_freecount = cpu_to_be32(cur->bc_rec.i.ir_freecount);
159         rec->inobt.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
160 }
161
162 /*
163  * initial value of ptr for lookup
164  */
165 STATIC void
166 xfs_inobt_init_ptr_from_cur(
167         struct xfs_btree_cur    *cur,
168         union xfs_btree_ptr     *ptr)
169 {
170         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
171
172         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
173
174         ptr->s = agi->agi_root;
175 }
176
177 STATIC __int64_t
178 xfs_inobt_key_diff(
179         struct xfs_btree_cur    *cur,
180         union xfs_btree_key     *key)
181 {
182         return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
183                           cur->bc_rec.i.ir_startino;
184 }
185
186 #ifdef DEBUG
187 STATIC int
188 xfs_inobt_keys_inorder(
189         struct xfs_btree_cur    *cur,
190         union xfs_btree_key     *k1,
191         union xfs_btree_key     *k2)
192 {
193         return be32_to_cpu(k1->inobt.ir_startino) <
194                 be32_to_cpu(k2->inobt.ir_startino);
195 }
196
197 STATIC int
198 xfs_inobt_recs_inorder(
199         struct xfs_btree_cur    *cur,
200         union xfs_btree_rec     *r1,
201         union xfs_btree_rec     *r2)
202 {
203         return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
204                 be32_to_cpu(r2->inobt.ir_startino);
205 }
206 #endif  /* DEBUG */
207
208 #ifdef XFS_BTREE_TRACE
209 ktrace_t        *xfs_inobt_trace_buf;
210
211 STATIC void
212 xfs_inobt_trace_enter(
213         struct xfs_btree_cur    *cur,
214         const char              *func,
215         char                    *s,
216         int                     type,
217         int                     line,
218         __psunsigned_t          a0,
219         __psunsigned_t          a1,
220         __psunsigned_t          a2,
221         __psunsigned_t          a3,
222         __psunsigned_t          a4,
223         __psunsigned_t          a5,
224         __psunsigned_t          a6,
225         __psunsigned_t          a7,
226         __psunsigned_t          a8,
227         __psunsigned_t          a9,
228         __psunsigned_t          a10)
229 {
230         ktrace_enter(xfs_inobt_trace_buf, (void *)(__psint_t)type,
231                 (void *)func, (void *)s, NULL, (void *)cur,
232                 (void *)a0, (void *)a1, (void *)a2, (void *)a3,
233                 (void *)a4, (void *)a5, (void *)a6, (void *)a7,
234                 (void *)a8, (void *)a9, (void *)a10);
235 }
236
237 STATIC void
238 xfs_inobt_trace_cursor(
239         struct xfs_btree_cur    *cur,
240         __uint32_t              *s0,
241         __uint64_t              *l0,
242         __uint64_t              *l1)
243 {
244         *s0 = cur->bc_private.a.agno;
245         *l0 = cur->bc_rec.i.ir_startino;
246         *l1 = cur->bc_rec.i.ir_free;
247 }
248
249 STATIC void
250 xfs_inobt_trace_key(
251         struct xfs_btree_cur    *cur,
252         union xfs_btree_key     *key,
253         __uint64_t              *l0,
254         __uint64_t              *l1)
255 {
256         *l0 = be32_to_cpu(key->inobt.ir_startino);
257         *l1 = 0;
258 }
259
260 STATIC void
261 xfs_inobt_trace_record(
262         struct xfs_btree_cur    *cur,
263         union xfs_btree_rec     *rec,
264         __uint64_t              *l0,
265         __uint64_t              *l1,
266         __uint64_t              *l2)
267 {
268         *l0 = be32_to_cpu(rec->inobt.ir_startino);
269         *l1 = be32_to_cpu(rec->inobt.ir_freecount);
270         *l2 = be64_to_cpu(rec->inobt.ir_free);
271 }
272 #endif /* XFS_BTREE_TRACE */
273
274 static const struct xfs_btree_ops xfs_inobt_ops = {
275         .rec_len                = sizeof(xfs_inobt_rec_t),
276         .key_len                = sizeof(xfs_inobt_key_t),
277
278         .dup_cursor             = xfs_inobt_dup_cursor,
279         .set_root               = xfs_inobt_set_root,
280         .alloc_block            = xfs_inobt_alloc_block,
281         .free_block             = xfs_inobt_free_block,
282         .get_minrecs            = xfs_inobt_get_minrecs,
283         .get_maxrecs            = xfs_inobt_get_maxrecs,
284         .init_key_from_rec      = xfs_inobt_init_key_from_rec,
285         .init_rec_from_key      = xfs_inobt_init_rec_from_key,
286         .init_rec_from_cur      = xfs_inobt_init_rec_from_cur,
287         .init_ptr_from_cur      = xfs_inobt_init_ptr_from_cur,
288         .key_diff               = xfs_inobt_key_diff,
289
290 #ifdef DEBUG
291         .keys_inorder           = xfs_inobt_keys_inorder,
292         .recs_inorder           = xfs_inobt_recs_inorder,
293 #endif
294
295 #ifdef XFS_BTREE_TRACE
296         .trace_enter            = xfs_inobt_trace_enter,
297         .trace_cursor           = xfs_inobt_trace_cursor,
298         .trace_key              = xfs_inobt_trace_key,
299         .trace_record           = xfs_inobt_trace_record,
300 #endif
301 };
302
303 /*
304  * Allocate a new inode btree cursor.
305  */
306 struct xfs_btree_cur *                          /* new inode btree cursor */
307 xfs_inobt_init_cursor(
308         struct xfs_mount        *mp,            /* file system mount point */
309         struct xfs_trans        *tp,            /* transaction pointer */
310         struct xfs_buf          *agbp,          /* buffer for agi structure */
311         xfs_agnumber_t          agno)           /* allocation group number */
312 {
313         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
314         struct xfs_btree_cur    *cur;
315
316         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
317
318         cur->bc_tp = tp;
319         cur->bc_mp = mp;
320         cur->bc_nlevels = be32_to_cpu(agi->agi_level);
321         cur->bc_btnum = XFS_BTNUM_INO;
322         cur->bc_blocklog = mp->m_sb.sb_blocklog;
323
324         cur->bc_ops = &xfs_inobt_ops;
325
326         cur->bc_private.a.agbp = agbp;
327         cur->bc_private.a.agno = agno;
328
329         return cur;
330 }
331
332 /*
333  * Calculate number of records in an inobt btree block.
334  */
335 int
336 xfs_inobt_maxrecs(
337         struct xfs_mount        *mp,
338         int                     blocklen,
339         int                     leaf)
340 {
341         blocklen -= XFS_INOBT_BLOCK_LEN(mp);
342
343         if (leaf)
344                 return blocklen / sizeof(xfs_inobt_rec_t);
345         return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));
346 }