b726e10d2c1c18bafa355663d822f8b9ef441d67
[linux-2.6.git] / fs / xfs / xfs_alloc_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_dir2.h"
28 #include "xfs_dmapi.h"
29 #include "xfs_mount.h"
30 #include "xfs_bmap_btree.h"
31 #include "xfs_alloc_btree.h"
32 #include "xfs_ialloc_btree.h"
33 #include "xfs_dir2_sf.h"
34 #include "xfs_attr_sf.h"
35 #include "xfs_dinode.h"
36 #include "xfs_inode.h"
37 #include "xfs_btree.h"
38 #include "xfs_btree_trace.h"
39 #include "xfs_ialloc.h"
40 #include "xfs_alloc.h"
41 #include "xfs_error.h"
42 #include "xfs_trace.h"
43
44
45 STATIC struct xfs_btree_cur *
46 xfs_allocbt_dup_cursor(
47         struct xfs_btree_cur    *cur)
48 {
49         return xfs_allocbt_init_cursor(cur->bc_mp, cur->bc_tp,
50                         cur->bc_private.a.agbp, cur->bc_private.a.agno,
51                         cur->bc_btnum);
52 }
53
54 STATIC void
55 xfs_allocbt_set_root(
56         struct xfs_btree_cur    *cur,
57         union xfs_btree_ptr     *ptr,
58         int                     inc)
59 {
60         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
61         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
62         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
63         int                     btnum = cur->bc_btnum;
64         struct xfs_perag        *pag = xfs_perag_get(cur->bc_mp, seqno);
65
66         ASSERT(ptr->s != 0);
67
68         agf->agf_roots[btnum] = ptr->s;
69         be32_add_cpu(&agf->agf_levels[btnum], inc);
70         pag->pagf_levels[btnum] += inc;
71         xfs_perag_put(pag);
72
73         xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
74 }
75
76 STATIC int
77 xfs_allocbt_alloc_block(
78         struct xfs_btree_cur    *cur,
79         union xfs_btree_ptr     *start,
80         union xfs_btree_ptr     *new,
81         int                     length,
82         int                     *stat)
83 {
84         int                     error;
85         xfs_agblock_t           bno;
86
87         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
88
89         /* Allocate the new block from the freelist. If we can't, give up.  */
90         error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
91                                        &bno, 1);
92         if (error) {
93                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
94                 return error;
95         }
96
97         if (bno == NULLAGBLOCK) {
98                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
99                 *stat = 0;
100                 return 0;
101         }
102
103         xfs_trans_agbtree_delta(cur->bc_tp, 1);
104         new->s = cpu_to_be32(bno);
105
106         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
107         *stat = 1;
108         return 0;
109 }
110
111 STATIC int
112 xfs_allocbt_free_block(
113         struct xfs_btree_cur    *cur,
114         struct xfs_buf          *bp)
115 {
116         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
117         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
118         xfs_agblock_t           bno;
119         int                     error;
120
121         bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
122         error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
123         if (error)
124                 return error;
125
126         /*
127          * Since blocks move to the free list without the coordination used in
128          * xfs_bmap_finish, we can't allow block to be available for
129          * reallocation and non-transaction writing (user data) until we know
130          * that the transaction that moved it to the free list is permanently
131          * on disk. We track the blocks by declaring these blocks as "busy";
132          * the busy list is maintained on a per-ag basis and each transaction
133          * records which entries should be removed when the iclog commits to
134          * disk. If a busy block is allocated, the iclog is pushed up to the
135          * LSN that freed the block.
136          */
137         xfs_alloc_mark_busy(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1);
138         xfs_trans_agbtree_delta(cur->bc_tp, -1);
139         return 0;
140 }
141
142 /*
143  * Update the longest extent in the AGF
144  */
145 STATIC void
146 xfs_allocbt_update_lastrec(
147         struct xfs_btree_cur    *cur,
148         struct xfs_btree_block  *block,
149         union xfs_btree_rec     *rec,
150         int                     ptr,
151         int                     reason)
152 {
153         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
154         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
155         struct xfs_perag        *pag;
156         __be32                  len;
157         int                     numrecs;
158
159         ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
160
161         switch (reason) {
162         case LASTREC_UPDATE:
163                 /*
164                  * If this is the last leaf block and it's the last record,
165                  * then update the size of the longest extent in the AG.
166                  */
167                 if (ptr != xfs_btree_get_numrecs(block))
168                         return;
169                 len = rec->alloc.ar_blockcount;
170                 break;
171         case LASTREC_INSREC:
172                 if (be32_to_cpu(rec->alloc.ar_blockcount) <=
173                     be32_to_cpu(agf->agf_longest))
174                         return;
175                 len = rec->alloc.ar_blockcount;
176                 break;
177         case LASTREC_DELREC:
178                 numrecs = xfs_btree_get_numrecs(block);
179                 if (ptr <= numrecs)
180                         return;
181                 ASSERT(ptr == numrecs + 1);
182
183                 if (numrecs) {
184                         xfs_alloc_rec_t *rrp;
185
186                         rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
187                         len = rrp->ar_blockcount;
188                 } else {
189                         len = 0;
190                 }
191
192                 break;
193         default:
194                 ASSERT(0);
195                 return;
196         }
197
198         agf->agf_longest = len;
199         pag = xfs_perag_get(cur->bc_mp, seqno);
200         pag->pagf_longest = be32_to_cpu(len);
201         xfs_perag_put(pag);
202         xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
203 }
204
205 STATIC int
206 xfs_allocbt_get_minrecs(
207         struct xfs_btree_cur    *cur,
208         int                     level)
209 {
210         return cur->bc_mp->m_alloc_mnr[level != 0];
211 }
212
213 STATIC int
214 xfs_allocbt_get_maxrecs(
215         struct xfs_btree_cur    *cur,
216         int                     level)
217 {
218         return cur->bc_mp->m_alloc_mxr[level != 0];
219 }
220
221 STATIC void
222 xfs_allocbt_init_key_from_rec(
223         union xfs_btree_key     *key,
224         union xfs_btree_rec     *rec)
225 {
226         ASSERT(rec->alloc.ar_startblock != 0);
227
228         key->alloc.ar_startblock = rec->alloc.ar_startblock;
229         key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
230 }
231
232 STATIC void
233 xfs_allocbt_init_rec_from_key(
234         union xfs_btree_key     *key,
235         union xfs_btree_rec     *rec)
236 {
237         ASSERT(key->alloc.ar_startblock != 0);
238
239         rec->alloc.ar_startblock = key->alloc.ar_startblock;
240         rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
241 }
242
243 STATIC void
244 xfs_allocbt_init_rec_from_cur(
245         struct xfs_btree_cur    *cur,
246         union xfs_btree_rec     *rec)
247 {
248         ASSERT(cur->bc_rec.a.ar_startblock != 0);
249
250         rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
251         rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
252 }
253
254 STATIC void
255 xfs_allocbt_init_ptr_from_cur(
256         struct xfs_btree_cur    *cur,
257         union xfs_btree_ptr     *ptr)
258 {
259         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
260
261         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
262         ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
263
264         ptr->s = agf->agf_roots[cur->bc_btnum];
265 }
266
267 STATIC __int64_t
268 xfs_allocbt_key_diff(
269         struct xfs_btree_cur    *cur,
270         union xfs_btree_key     *key)
271 {
272         xfs_alloc_rec_incore_t  *rec = &cur->bc_rec.a;
273         xfs_alloc_key_t         *kp = &key->alloc;
274         __int64_t               diff;
275
276         if (cur->bc_btnum == XFS_BTNUM_BNO) {
277                 return (__int64_t)be32_to_cpu(kp->ar_startblock) -
278                                 rec->ar_startblock;
279         }
280
281         diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
282         if (diff)
283                 return diff;
284
285         return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
286 }
287
288 STATIC int
289 xfs_allocbt_kill_root(
290         struct xfs_btree_cur    *cur,
291         struct xfs_buf          *bp,
292         int                     level,
293         union xfs_btree_ptr     *newroot)
294 {
295         int                     error;
296
297         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
298         XFS_BTREE_STATS_INC(cur, killroot);
299
300         /*
301          * Update the root pointer, decreasing the level by 1 and then
302          * free the old root.
303          */
304         xfs_allocbt_set_root(cur, newroot, -1);
305         error = xfs_allocbt_free_block(cur, bp);
306         if (error) {
307                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
308                 return error;
309         }
310
311         XFS_BTREE_STATS_INC(cur, free);
312
313         xfs_btree_setbuf(cur, level, NULL);
314         cur->bc_nlevels--;
315
316         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
317         return 0;
318 }
319
320 #ifdef DEBUG
321 STATIC int
322 xfs_allocbt_keys_inorder(
323         struct xfs_btree_cur    *cur,
324         union xfs_btree_key     *k1,
325         union xfs_btree_key     *k2)
326 {
327         if (cur->bc_btnum == XFS_BTNUM_BNO) {
328                 return be32_to_cpu(k1->alloc.ar_startblock) <
329                        be32_to_cpu(k2->alloc.ar_startblock);
330         } else {
331                 return be32_to_cpu(k1->alloc.ar_blockcount) <
332                         be32_to_cpu(k2->alloc.ar_blockcount) ||
333                         (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
334                          be32_to_cpu(k1->alloc.ar_startblock) <
335                          be32_to_cpu(k2->alloc.ar_startblock));
336         }
337 }
338
339 STATIC int
340 xfs_allocbt_recs_inorder(
341         struct xfs_btree_cur    *cur,
342         union xfs_btree_rec     *r1,
343         union xfs_btree_rec     *r2)
344 {
345         if (cur->bc_btnum == XFS_BTNUM_BNO) {
346                 return be32_to_cpu(r1->alloc.ar_startblock) +
347                         be32_to_cpu(r1->alloc.ar_blockcount) <=
348                         be32_to_cpu(r2->alloc.ar_startblock);
349         } else {
350                 return be32_to_cpu(r1->alloc.ar_blockcount) <
351                         be32_to_cpu(r2->alloc.ar_blockcount) ||
352                         (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
353                          be32_to_cpu(r1->alloc.ar_startblock) <
354                          be32_to_cpu(r2->alloc.ar_startblock));
355         }
356 }
357 #endif  /* DEBUG */
358
359 #ifdef XFS_BTREE_TRACE
360 ktrace_t        *xfs_allocbt_trace_buf;
361
362 STATIC void
363 xfs_allocbt_trace_enter(
364         struct xfs_btree_cur    *cur,
365         const char              *func,
366         char                    *s,
367         int                     type,
368         int                     line,
369         __psunsigned_t          a0,
370         __psunsigned_t          a1,
371         __psunsigned_t          a2,
372         __psunsigned_t          a3,
373         __psunsigned_t          a4,
374         __psunsigned_t          a5,
375         __psunsigned_t          a6,
376         __psunsigned_t          a7,
377         __psunsigned_t          a8,
378         __psunsigned_t          a9,
379         __psunsigned_t          a10)
380 {
381         ktrace_enter(xfs_allocbt_trace_buf, (void *)(__psint_t)type,
382                 (void *)func, (void *)s, NULL, (void *)cur,
383                 (void *)a0, (void *)a1, (void *)a2, (void *)a3,
384                 (void *)a4, (void *)a5, (void *)a6, (void *)a7,
385                 (void *)a8, (void *)a9, (void *)a10);
386 }
387
388 STATIC void
389 xfs_allocbt_trace_cursor(
390         struct xfs_btree_cur    *cur,
391         __uint32_t              *s0,
392         __uint64_t              *l0,
393         __uint64_t              *l1)
394 {
395         *s0 = cur->bc_private.a.agno;
396         *l0 = cur->bc_rec.a.ar_startblock;
397         *l1 = cur->bc_rec.a.ar_blockcount;
398 }
399
400 STATIC void
401 xfs_allocbt_trace_key(
402         struct xfs_btree_cur    *cur,
403         union xfs_btree_key     *key,
404         __uint64_t              *l0,
405         __uint64_t              *l1)
406 {
407         *l0 = be32_to_cpu(key->alloc.ar_startblock);
408         *l1 = be32_to_cpu(key->alloc.ar_blockcount);
409 }
410
411 STATIC void
412 xfs_allocbt_trace_record(
413         struct xfs_btree_cur    *cur,
414         union xfs_btree_rec     *rec,
415         __uint64_t              *l0,
416         __uint64_t              *l1,
417         __uint64_t              *l2)
418 {
419         *l0 = be32_to_cpu(rec->alloc.ar_startblock);
420         *l1 = be32_to_cpu(rec->alloc.ar_blockcount);
421         *l2 = 0;
422 }
423 #endif /* XFS_BTREE_TRACE */
424
425 static const struct xfs_btree_ops xfs_allocbt_ops = {
426         .rec_len                = sizeof(xfs_alloc_rec_t),
427         .key_len                = sizeof(xfs_alloc_key_t),
428
429         .dup_cursor             = xfs_allocbt_dup_cursor,
430         .set_root               = xfs_allocbt_set_root,
431         .kill_root              = xfs_allocbt_kill_root,
432         .alloc_block            = xfs_allocbt_alloc_block,
433         .free_block             = xfs_allocbt_free_block,
434         .update_lastrec         = xfs_allocbt_update_lastrec,
435         .get_minrecs            = xfs_allocbt_get_minrecs,
436         .get_maxrecs            = xfs_allocbt_get_maxrecs,
437         .init_key_from_rec      = xfs_allocbt_init_key_from_rec,
438         .init_rec_from_key      = xfs_allocbt_init_rec_from_key,
439         .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
440         .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
441         .key_diff               = xfs_allocbt_key_diff,
442
443 #ifdef DEBUG
444         .keys_inorder           = xfs_allocbt_keys_inorder,
445         .recs_inorder           = xfs_allocbt_recs_inorder,
446 #endif
447
448 #ifdef XFS_BTREE_TRACE
449         .trace_enter            = xfs_allocbt_trace_enter,
450         .trace_cursor           = xfs_allocbt_trace_cursor,
451         .trace_key              = xfs_allocbt_trace_key,
452         .trace_record           = xfs_allocbt_trace_record,
453 #endif
454 };
455
456 /*
457  * Allocate a new allocation btree cursor.
458  */
459 struct xfs_btree_cur *                  /* new alloc btree cursor */
460 xfs_allocbt_init_cursor(
461         struct xfs_mount        *mp,            /* file system mount point */
462         struct xfs_trans        *tp,            /* transaction pointer */
463         struct xfs_buf          *agbp,          /* buffer for agf structure */
464         xfs_agnumber_t          agno,           /* allocation group number */
465         xfs_btnum_t             btnum)          /* btree identifier */
466 {
467         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
468         struct xfs_btree_cur    *cur;
469
470         ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
471
472         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
473
474         cur->bc_tp = tp;
475         cur->bc_mp = mp;
476         cur->bc_nlevels = be32_to_cpu(agf->agf_levels[btnum]);
477         cur->bc_btnum = btnum;
478         cur->bc_blocklog = mp->m_sb.sb_blocklog;
479
480         cur->bc_ops = &xfs_allocbt_ops;
481         if (btnum == XFS_BTNUM_CNT)
482                 cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
483
484         cur->bc_private.a.agbp = agbp;
485         cur->bc_private.a.agno = agno;
486
487         return cur;
488 }
489
490 /*
491  * Calculate number of records in an alloc btree block.
492  */
493 int
494 xfs_allocbt_maxrecs(
495         struct xfs_mount        *mp,
496         int                     blocklen,
497         int                     leaf)
498 {
499         blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
500
501         if (leaf)
502                 return blocklen / sizeof(xfs_alloc_rec_t);
503         return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
504 }