Merge branch 'akpm'
[linux-2.6/next.git] / fs / xfs / xfs_alloc_btree.c
blobffb3386e45c15628d04c202cdf8cc9e3940e03be
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_alloc.h"
35 #include "xfs_error.h"
36 #include "xfs_trace.h"
39 STATIC struct xfs_btree_cur *
40 xfs_allocbt_dup_cursor(
41 struct xfs_btree_cur *cur)
43 return xfs_allocbt_init_cursor(cur->bc_mp, cur->bc_tp,
44 cur->bc_private.a.agbp, cur->bc_private.a.agno,
45 cur->bc_btnum);
48 STATIC void
49 xfs_allocbt_set_root(
50 struct xfs_btree_cur *cur,
51 union xfs_btree_ptr *ptr,
52 int inc)
54 struct xfs_buf *agbp = cur->bc_private.a.agbp;
55 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
56 xfs_agnumber_t seqno = be32_to_cpu(agf->agf_seqno);
57 int btnum = cur->bc_btnum;
58 struct xfs_perag *pag = xfs_perag_get(cur->bc_mp, seqno);
60 ASSERT(ptr->s != 0);
62 agf->agf_roots[btnum] = ptr->s;
63 be32_add_cpu(&agf->agf_levels[btnum], inc);
64 pag->pagf_levels[btnum] += inc;
65 xfs_perag_put(pag);
67 xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
70 STATIC int
71 xfs_allocbt_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)
78 int error;
79 xfs_agblock_t bno;
81 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
83 /* Allocate the new block from the freelist. If we can't, give up. */
84 error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
85 &bno, 1);
86 if (error) {
87 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
88 return error;
91 if (bno == NULLAGBLOCK) {
92 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
93 *stat = 0;
94 return 0;
97 xfs_alloc_busy_reuse(cur->bc_mp, cur->bc_private.a.agno, bno, 1, false);
99 xfs_trans_agbtree_delta(cur->bc_tp, 1);
100 new->s = cpu_to_be32(bno);
102 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
103 *stat = 1;
104 return 0;
107 STATIC int
108 xfs_allocbt_free_block(
109 struct xfs_btree_cur *cur,
110 struct xfs_buf *bp)
112 struct xfs_buf *agbp = cur->bc_private.a.agbp;
113 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
114 xfs_agblock_t bno;
115 int error;
117 bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
118 error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
119 if (error)
120 return error;
122 xfs_alloc_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
123 XFS_ALLOC_BUSY_SKIP_DISCARD);
124 xfs_trans_agbtree_delta(cur->bc_tp, -1);
125 return 0;
129 * Update the longest extent in the AGF
131 STATIC void
132 xfs_allocbt_update_lastrec(
133 struct xfs_btree_cur *cur,
134 struct xfs_btree_block *block,
135 union xfs_btree_rec *rec,
136 int ptr,
137 int reason)
139 struct xfs_agf *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
140 xfs_agnumber_t seqno = be32_to_cpu(agf->agf_seqno);
141 struct xfs_perag *pag;
142 __be32 len;
143 int numrecs;
145 ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
147 switch (reason) {
148 case LASTREC_UPDATE:
150 * If this is the last leaf block and it's the last record,
151 * then update the size of the longest extent in the AG.
153 if (ptr != xfs_btree_get_numrecs(block))
154 return;
155 len = rec->alloc.ar_blockcount;
156 break;
157 case LASTREC_INSREC:
158 if (be32_to_cpu(rec->alloc.ar_blockcount) <=
159 be32_to_cpu(agf->agf_longest))
160 return;
161 len = rec->alloc.ar_blockcount;
162 break;
163 case LASTREC_DELREC:
164 numrecs = xfs_btree_get_numrecs(block);
165 if (ptr <= numrecs)
166 return;
167 ASSERT(ptr == numrecs + 1);
169 if (numrecs) {
170 xfs_alloc_rec_t *rrp;
172 rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
173 len = rrp->ar_blockcount;
174 } else {
175 len = 0;
178 break;
179 default:
180 ASSERT(0);
181 return;
184 agf->agf_longest = len;
185 pag = xfs_perag_get(cur->bc_mp, seqno);
186 pag->pagf_longest = be32_to_cpu(len);
187 xfs_perag_put(pag);
188 xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
191 STATIC int
192 xfs_allocbt_get_minrecs(
193 struct xfs_btree_cur *cur,
194 int level)
196 return cur->bc_mp->m_alloc_mnr[level != 0];
199 STATIC int
200 xfs_allocbt_get_maxrecs(
201 struct xfs_btree_cur *cur,
202 int level)
204 return cur->bc_mp->m_alloc_mxr[level != 0];
207 STATIC void
208 xfs_allocbt_init_key_from_rec(
209 union xfs_btree_key *key,
210 union xfs_btree_rec *rec)
212 ASSERT(rec->alloc.ar_startblock != 0);
214 key->alloc.ar_startblock = rec->alloc.ar_startblock;
215 key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
218 STATIC void
219 xfs_allocbt_init_rec_from_key(
220 union xfs_btree_key *key,
221 union xfs_btree_rec *rec)
223 ASSERT(key->alloc.ar_startblock != 0);
225 rec->alloc.ar_startblock = key->alloc.ar_startblock;
226 rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
229 STATIC void
230 xfs_allocbt_init_rec_from_cur(
231 struct xfs_btree_cur *cur,
232 union xfs_btree_rec *rec)
234 ASSERT(cur->bc_rec.a.ar_startblock != 0);
236 rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
237 rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
240 STATIC void
241 xfs_allocbt_init_ptr_from_cur(
242 struct xfs_btree_cur *cur,
243 union xfs_btree_ptr *ptr)
245 struct xfs_agf *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
247 ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
248 ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
250 ptr->s = agf->agf_roots[cur->bc_btnum];
253 STATIC __int64_t
254 xfs_allocbt_key_diff(
255 struct xfs_btree_cur *cur,
256 union xfs_btree_key *key)
258 xfs_alloc_rec_incore_t *rec = &cur->bc_rec.a;
259 xfs_alloc_key_t *kp = &key->alloc;
260 __int64_t diff;
262 if (cur->bc_btnum == XFS_BTNUM_BNO) {
263 return (__int64_t)be32_to_cpu(kp->ar_startblock) -
264 rec->ar_startblock;
267 diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
268 if (diff)
269 return diff;
271 return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
274 #ifdef DEBUG
275 STATIC int
276 xfs_allocbt_keys_inorder(
277 struct xfs_btree_cur *cur,
278 union xfs_btree_key *k1,
279 union xfs_btree_key *k2)
281 if (cur->bc_btnum == XFS_BTNUM_BNO) {
282 return be32_to_cpu(k1->alloc.ar_startblock) <
283 be32_to_cpu(k2->alloc.ar_startblock);
284 } else {
285 return be32_to_cpu(k1->alloc.ar_blockcount) <
286 be32_to_cpu(k2->alloc.ar_blockcount) ||
287 (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
288 be32_to_cpu(k1->alloc.ar_startblock) <
289 be32_to_cpu(k2->alloc.ar_startblock));
293 STATIC int
294 xfs_allocbt_recs_inorder(
295 struct xfs_btree_cur *cur,
296 union xfs_btree_rec *r1,
297 union xfs_btree_rec *r2)
299 if (cur->bc_btnum == XFS_BTNUM_BNO) {
300 return be32_to_cpu(r1->alloc.ar_startblock) +
301 be32_to_cpu(r1->alloc.ar_blockcount) <=
302 be32_to_cpu(r2->alloc.ar_startblock);
303 } else {
304 return be32_to_cpu(r1->alloc.ar_blockcount) <
305 be32_to_cpu(r2->alloc.ar_blockcount) ||
306 (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
307 be32_to_cpu(r1->alloc.ar_startblock) <
308 be32_to_cpu(r2->alloc.ar_startblock));
311 #endif /* DEBUG */
313 static const struct xfs_btree_ops xfs_allocbt_ops = {
314 .rec_len = sizeof(xfs_alloc_rec_t),
315 .key_len = sizeof(xfs_alloc_key_t),
317 .dup_cursor = xfs_allocbt_dup_cursor,
318 .set_root = xfs_allocbt_set_root,
319 .alloc_block = xfs_allocbt_alloc_block,
320 .free_block = xfs_allocbt_free_block,
321 .update_lastrec = xfs_allocbt_update_lastrec,
322 .get_minrecs = xfs_allocbt_get_minrecs,
323 .get_maxrecs = xfs_allocbt_get_maxrecs,
324 .init_key_from_rec = xfs_allocbt_init_key_from_rec,
325 .init_rec_from_key = xfs_allocbt_init_rec_from_key,
326 .init_rec_from_cur = xfs_allocbt_init_rec_from_cur,
327 .init_ptr_from_cur = xfs_allocbt_init_ptr_from_cur,
328 .key_diff = xfs_allocbt_key_diff,
329 #ifdef DEBUG
330 .keys_inorder = xfs_allocbt_keys_inorder,
331 .recs_inorder = xfs_allocbt_recs_inorder,
332 #endif
336 * Allocate a new allocation btree cursor.
338 struct xfs_btree_cur * /* new alloc btree cursor */
339 xfs_allocbt_init_cursor(
340 struct xfs_mount *mp, /* file system mount point */
341 struct xfs_trans *tp, /* transaction pointer */
342 struct xfs_buf *agbp, /* buffer for agf structure */
343 xfs_agnumber_t agno, /* allocation group number */
344 xfs_btnum_t btnum) /* btree identifier */
346 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
347 struct xfs_btree_cur *cur;
349 ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
351 cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
353 cur->bc_tp = tp;
354 cur->bc_mp = mp;
355 cur->bc_btnum = btnum;
356 cur->bc_blocklog = mp->m_sb.sb_blocklog;
357 cur->bc_ops = &xfs_allocbt_ops;
359 if (btnum == XFS_BTNUM_CNT) {
360 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
361 cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
362 } else {
363 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
366 cur->bc_private.a.agbp = agbp;
367 cur->bc_private.a.agno = agno;
369 return cur;
373 * Calculate number of records in an alloc btree block.
376 xfs_allocbt_maxrecs(
377 struct xfs_mount *mp,
378 int blocklen,
379 int leaf)
381 blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
383 if (leaf)
384 return blocklen / sizeof(xfs_alloc_rec_t);
385 return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));