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xfs: create a shared header file for format-related information
[deliverable/linux.git] / fs / xfs / xfs_btree.c
CommitLineData
1da177e4 1/*
7b718769
NS		 2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
1da177e4 4 *
7b718769
NS		 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
1da177e4
LT		 7 * published by the Free Software Foundation.
8 *
7b718769
NS		 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.
1da177e4 13 *
7b718769
NS		 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
1da177e4 17 */
1da177e4 18#include "xfs.h"
a844f451 19#include "xfs_fs.h"
70a9883c 20#include "xfs_shared.h"
a844f451 21#include "xfs_bit.h"
1da177e4
LT		 22#include "xfs_log.h"
23#include "xfs_trans.h"
24#include "xfs_sb.h"
25#include "xfs_ag.h"
1da177e4 26#include "xfs_mount.h"
1da177e4 27#include "xfs_bmap_btree.h"
a844f451 28#include "xfs_alloc_btree.h"
1da177e4 29#include "xfs_ialloc_btree.h"
1da177e4
LT		 30#include "xfs_dinode.h"
31#include "xfs_inode.h"
38bb7423 32#include "xfs_inode_item.h"
ee1a47ab 33#include "xfs_buf_item.h"
a844f451 34#include "xfs_btree.h"
1da177e4 35#include "xfs_error.h"
0b1b213f 36#include "xfs_trace.h"
ee1a47ab 37#include "xfs_cksum.h"
1da177e4
LT		 38
39/*
40 * Cursor allocation zone.
41 */
42kmem_zone_t *xfs_btree_cur_zone;
43
44/*
45 * Btree magic numbers.
46 */
ee1a47ab
CH		 47static const __uint32_t xfs_magics[2][XFS_BTNUM_MAX] = {
48 { XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC },
49 { XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC,
50 XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC }
1da177e4 51};
ee1a47ab
CH		 52#define xfs_btree_magic(cur) \
53 xfs_magics[!!((cur)->bc_flags & XFS_BTREE_CRC_BLOCKS)][cur->bc_btnum]
1da177e4 54
1da177e4 55
7cc95a82 56STATIC int /* error (0 or EFSCORRUPTED) */
a23f6ef8
CH		 57xfs_btree_check_lblock(
58 struct xfs_btree_cur *cur, /* btree cursor */
7cc95a82 59 struct xfs_btree_block *block, /* btree long form block pointer */
a23f6ef8
CH		 60 int level, /* level of the btree block */
61 struct xfs_buf *bp) /* buffer for block, if any */
62{
ee1a47ab 63 int lblock_ok = 1; /* block passes checks */
a23f6ef8
CH		 64 struct xfs_mount *mp; /* file system mount point */
65
66 mp = cur->bc_mp;
ee1a47ab
CH		 67
68 if (xfs_sb_version_hascrc(&mp->m_sb)) {
69 lblock_ok = lblock_ok &&
70 uuid_equal(&block->bb_u.l.bb_uuid, &mp->m_sb.sb_uuid) &&
71 block->bb_u.l.bb_blkno == cpu_to_be64(
72 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
73 }
74
75 lblock_ok = lblock_ok &&
76 be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) &&
a23f6ef8
CH		 77 be16_to_cpu(block->bb_level) == level &&
78 be16_to_cpu(block->bb_numrecs) <=
ce5e42db 79 cur->bc_ops->get_maxrecs(cur, level) &&
7cc95a82 80 block->bb_u.l.bb_leftsib &&
69ef921b 81 (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLDFSBNO) ||
7cc95a82 82 XFS_FSB_SANITY_CHECK(mp,
ee1a47ab 83 be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
7cc95a82 84 block->bb_u.l.bb_rightsib &&
69ef921b 85 (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO) ||
7cc95a82 86 XFS_FSB_SANITY_CHECK(mp,
ee1a47ab
CH		 87 be64_to_cpu(block->bb_u.l.bb_rightsib)));
88
a23f6ef8
CH		 89 if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
90 XFS_ERRTAG_BTREE_CHECK_LBLOCK,
91 XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
92 if (bp)
0b1b213f 93 trace_xfs_btree_corrupt(bp, _RET_IP_);
ee1a47ab 94 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
a23f6ef8
CH		 95 return XFS_ERROR(EFSCORRUPTED);
96 }
97 return 0;
98}
99
3cc7524c 100STATIC int /* error (0 or EFSCORRUPTED) */
1da177e4 101xfs_btree_check_sblock(
a23f6ef8 102 struct xfs_btree_cur *cur, /* btree cursor */
7cc95a82 103 struct xfs_btree_block *block, /* btree short form block pointer */
1da177e4 104 int level, /* level of the btree block */
a23f6ef8 105 struct xfs_buf *bp) /* buffer containing block */
1da177e4 106{
ee1a47ab 107 struct xfs_mount *mp; /* file system mount point */
a23f6ef8
CH		 108 struct xfs_buf *agbp; /* buffer for ag. freespace struct */
109 struct xfs_agf *agf; /* ag. freespace structure */
1da177e4 110 xfs_agblock_t agflen; /* native ag. freespace length */
ee1a47ab 111 int sblock_ok = 1; /* block passes checks */
1da177e4 112
ee1a47ab 113 mp = cur->bc_mp;
1da177e4
LT		 114 agbp = cur->bc_private.a.agbp;
115 agf = XFS_BUF_TO_AGF(agbp);
16259e7d 116 agflen = be32_to_cpu(agf->agf_length);
ee1a47ab
CH		 117
118 if (xfs_sb_version_hascrc(&mp->m_sb)) {
119 sblock_ok = sblock_ok &&
120 uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid) &&
121 block->bb_u.s.bb_blkno == cpu_to_be64(
122 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
123 }
124
125 sblock_ok = sblock_ok &&
126 be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) &&
16259e7d
CH		 127 be16_to_cpu(block->bb_level) == level &&
128 be16_to_cpu(block->bb_numrecs) <=
ce5e42db 129 cur->bc_ops->get_maxrecs(cur, level) &&
69ef921b 130 (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) ||
7cc95a82
CH		 131 be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
132 block->bb_u.s.bb_leftsib &&
69ef921b 133 (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) ||
7cc95a82
CH		 134 be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
135 block->bb_u.s.bb_rightsib;
ee1a47ab
CH		 136
137 if (unlikely(XFS_TEST_ERROR(!sblock_ok, mp,
1da177e4
LT		 138 XFS_ERRTAG_BTREE_CHECK_SBLOCK,
139 XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
140 if (bp)
0b1b213f 141 trace_xfs_btree_corrupt(bp, _RET_IP_);
ee1a47ab 142 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
1da177e4
LT		 143 return XFS_ERROR(EFSCORRUPTED);
144 }
145 return 0;
146}
147
148/*
a23f6ef8
CH		 149 * Debug routine: check that block header is ok.
150 */
151int
152xfs_btree_check_block(
153 struct xfs_btree_cur *cur, /* btree cursor */
154 struct xfs_btree_block *block, /* generic btree block pointer */
155 int level, /* level of the btree block */
156 struct xfs_buf *bp) /* buffer containing block, if any */
157{
7cc95a82
CH		 158 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
159 return xfs_btree_check_lblock(cur, block, level, bp);
160 else
161 return xfs_btree_check_sblock(cur, block, level, bp);
a23f6ef8
CH		 162}
163
164/*
165 * Check that (long) pointer is ok.
166 */
167int /* error (0 or EFSCORRUPTED) */
168xfs_btree_check_lptr(
169 struct xfs_btree_cur *cur, /* btree cursor */
170 xfs_dfsbno_t bno, /* btree block disk address */
171 int level) /* btree block level */
172{
173 XFS_WANT_CORRUPTED_RETURN(
174 level > 0 &&
175 bno != NULLDFSBNO &&
176 XFS_FSB_SANITY_CHECK(cur->bc_mp, bno));
177 return 0;
178}
179
24ee0e49 180#ifdef DEBUG
a23f6ef8
CH		 181/*
182 * Check that (short) pointer is ok.
1da177e4 183 */
3cc7524c 184STATIC int /* error (0 or EFSCORRUPTED) */
1da177e4 185xfs_btree_check_sptr(
a23f6ef8
CH		 186 struct xfs_btree_cur *cur, /* btree cursor */
187 xfs_agblock_t bno, /* btree block disk address */
188 int level) /* btree block level */
1da177e4 189{
a23f6ef8 190 xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks;
1da177e4 191
1da177e4
LT		 192 XFS_WANT_CORRUPTED_RETURN(
193 level > 0 &&
a23f6ef8
CH		 194 bno != NULLAGBLOCK &&
195 bno != 0 &&
196 bno < agblocks);
1da177e4
LT		 197 return 0;
198}
199
a23f6ef8
CH		 200/*
201 * Check that block ptr is ok.
202 */
3cc7524c 203STATIC int /* error (0 or EFSCORRUPTED) */
a23f6ef8
CH		 204xfs_btree_check_ptr(
205 struct xfs_btree_cur *cur, /* btree cursor */
206 union xfs_btree_ptr *ptr, /* btree block disk address */
207 int index, /* offset from ptr to check */
208 int level) /* btree block level */
209{
210 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
211 return xfs_btree_check_lptr(cur,
212 be64_to_cpu((&ptr->l)[index]), level);
213 } else {
214 return xfs_btree_check_sptr(cur,
215 be32_to_cpu((&ptr->s)[index]), level);
216 }
217}
24ee0e49 218#endif
a23f6ef8 219
ee1a47ab
CH		 220/*
221 * Calculate CRC on the whole btree block and stuff it into the
222 * long-form btree header.
223 *
224 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
225 * it into the buffer so recovery knows what the last modifcation was that made
226 * it to disk.
227 */
228void
229xfs_btree_lblock_calc_crc(
230 struct xfs_buf *bp)
231{
232 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
233 struct xfs_buf_log_item *bip = bp->b_fspriv;
234
235 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
236 return;
237 if (bip)
238 block->bb_u.l.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
239 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
240 XFS_BTREE_LBLOCK_CRC_OFF);
241}
242
243bool
244xfs_btree_lblock_verify_crc(
245 struct xfs_buf *bp)
246{
247 if (xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
248 return xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
249 XFS_BTREE_LBLOCK_CRC_OFF);
250 return true;
251}
252
253/*
254 * Calculate CRC on the whole btree block and stuff it into the
255 * short-form btree header.
256 *
257 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
258 * it into the buffer so recovery knows what the last modifcation was that made
259 * it to disk.
260 */
261void
262xfs_btree_sblock_calc_crc(
263 struct xfs_buf *bp)
264{
265 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
266 struct xfs_buf_log_item *bip = bp->b_fspriv;
267
268 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
269 return;
270 if (bip)
271 block->bb_u.s.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
272 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
273 XFS_BTREE_SBLOCK_CRC_OFF);
274}
275
276bool
277xfs_btree_sblock_verify_crc(
278 struct xfs_buf *bp)
279{
280 if (xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
281 return xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
282 XFS_BTREE_SBLOCK_CRC_OFF);
283 return true;
284}
285
1da177e4
LT		 286/*
287 * Delete the btree cursor.
288 */
289void
290xfs_btree_del_cursor(
291 xfs_btree_cur_t *cur, /* btree cursor */
292 int error) /* del because of error */
293{
294 int i; /* btree level */
295
296 /*
297 * Clear the buffer pointers, and release the buffers.
298 * If we're doing this in the face of an error, we
299 * need to make sure to inspect all of the entries
300 * in the bc_bufs array for buffers to be unlocked.
301 * This is because some of the btree code works from
302 * level n down to 0, and if we get an error along
303 * the way we won't have initialized all the entries
304 * down to 0.
305 */
306 for (i = 0; i < cur->bc_nlevels; i++) {
307 if (cur->bc_bufs[i])
c0e59e1a 308 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
1da177e4
LT		 309 else if (!error)
310 break;
311 }
312 /*
313 * Can't free a bmap cursor without having dealt with the
314 * allocated indirect blocks' accounting.
315 */
316 ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP ||
317 cur->bc_private.b.allocated == 0);
318 /*
319 * Free the cursor.
320 */
321 kmem_zone_free(xfs_btree_cur_zone, cur);
322}
323
324/*
325 * Duplicate the btree cursor.
326 * Allocate a new one, copy the record, re-get the buffers.
327 */
328int /* error */
329xfs_btree_dup_cursor(
330 xfs_btree_cur_t *cur, /* input cursor */
331 xfs_btree_cur_t **ncur) /* output cursor */
332{
333 xfs_buf_t *bp; /* btree block's buffer pointer */
334 int error; /* error return value */
335 int i; /* level number of btree block */
336 xfs_mount_t *mp; /* mount structure for filesystem */
337 xfs_btree_cur_t *new; /* new cursor value */
338 xfs_trans_t *tp; /* transaction pointer, can be NULL */
339
340 tp = cur->bc_tp;
341 mp = cur->bc_mp;
561f7d17 342
1da177e4
LT		 343 /*
344 * Allocate a new cursor like the old one.
345 */
561f7d17
CH		 346 new = cur->bc_ops->dup_cursor(cur);
347
1da177e4
LT		 348 /*
349 * Copy the record currently in the cursor.
350 */
351 new->bc_rec = cur->bc_rec;
561f7d17 352
1da177e4
LT		 353 /*
354 * For each level current, re-get the buffer and copy the ptr value.
355 */
356 for (i = 0; i < new->bc_nlevels; i++) {
357 new->bc_ptrs[i] = cur->bc_ptrs[i];
358 new->bc_ra[i] = cur->bc_ra[i];
c3f8fc73
DC		 359 bp = cur->bc_bufs[i];
360 if (bp) {
361 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
362 XFS_BUF_ADDR(bp), mp->m_bsize,
3d3e6f64 363 0, &bp,
1813dd64 364 cur->bc_ops->buf_ops);
c3f8fc73 365 if (error) {
1da177e4
LT		 366 xfs_btree_del_cursor(new, error);
367 *ncur = NULL;
368 return error;
369 }
ee1a47ab
CH		 370 }
371 new->bc_bufs[i] = bp;
1da177e4 372 }
1da177e4
LT		 373 *ncur = new;
374 return 0;
375}
376
65f1eaea
CH		 377/*
378 * XFS btree block layout and addressing:
379 *
380 * There are two types of blocks in the btree: leaf and non-leaf blocks.
381 *
382 * The leaf record start with a header then followed by records containing
383 * the values. A non-leaf block also starts with the same header, and
384 * then first contains lookup keys followed by an equal number of pointers
385 * to the btree blocks at the previous level.
386 *
387 * +--------+-------+-------+-------+-------+-------+-------+
388 * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
389 * +--------+-------+-------+-------+-------+-------+-------+
390 *
391 * +--------+-------+-------+-------+-------+-------+-------+
392 * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
393 * +--------+-------+-------+-------+-------+-------+-------+
394 *
395 * The header is called struct xfs_btree_block for reasons better left unknown
396 * and comes in different versions for short (32bit) and long (64bit) block
397 * pointers. The record and key structures are defined by the btree instances
398 * and opaque to the btree core. The block pointers are simple disk endian
399 * integers, available in a short (32bit) and long (64bit) variant.
400 *
401 * The helpers below calculate the offset of a given record, key or pointer
402 * into a btree block (xfs_btree_*_offset) or return a pointer to the given
403 * record, key or pointer (xfs_btree_*_addr). Note that all addressing
404 * inside the btree block is done using indices starting at one, not zero!
405 */
406
407/*
408 * Return size of the btree block header for this btree instance.
409 */
410static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
411{
ee1a47ab
CH		 412 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
413 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
414 return XFS_BTREE_LBLOCK_CRC_LEN;
415 return XFS_BTREE_LBLOCK_LEN;
416 }
417 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
418 return XFS_BTREE_SBLOCK_CRC_LEN;
419 return XFS_BTREE_SBLOCK_LEN;
65f1eaea
CH		 420}
421
422/*
423 * Return size of btree block pointers for this btree instance.
424 */
425static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
426{
427 return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
428 sizeof(__be64) : sizeof(__be32);
429}
430
431/*
432 * Calculate offset of the n-th record in a btree block.
433 */
434STATIC size_t
435xfs_btree_rec_offset(
436 struct xfs_btree_cur *cur,
437 int n)
438{
439 return xfs_btree_block_len(cur) +
440 (n - 1) * cur->bc_ops->rec_len;
441}
442
443/*
444 * Calculate offset of the n-th key in a btree block.
445 */
446STATIC size_t
447xfs_btree_key_offset(
448 struct xfs_btree_cur *cur,
449 int n)
450{
451 return xfs_btree_block_len(cur) +
452 (n - 1) * cur->bc_ops->key_len;
453}
454
455/*
456 * Calculate offset of the n-th block pointer in a btree block.
457 */
458STATIC size_t
459xfs_btree_ptr_offset(
460 struct xfs_btree_cur *cur,
461 int n,
462 int level)
463{
464 return xfs_btree_block_len(cur) +
465 cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
466 (n - 1) * xfs_btree_ptr_len(cur);
467}
468
469/*
470 * Return a pointer to the n-th record in the btree block.
471 */
472STATIC union xfs_btree_rec *
473xfs_btree_rec_addr(
474 struct xfs_btree_cur *cur,
475 int n,
476 struct xfs_btree_block *block)
477{
478 return (union xfs_btree_rec *)
479 ((char *)block + xfs_btree_rec_offset(cur, n));
480}
481
482/*
483 * Return a pointer to the n-th key in the btree block.
484 */
485STATIC union xfs_btree_key *
486xfs_btree_key_addr(
487 struct xfs_btree_cur *cur,
488 int n,
489 struct xfs_btree_block *block)
490{
491 return (union xfs_btree_key *)
492 ((char *)block + xfs_btree_key_offset(cur, n));
493}
494
495/*
496 * Return a pointer to the n-th block pointer in the btree block.
497 */
498STATIC union xfs_btree_ptr *
499xfs_btree_ptr_addr(
500 struct xfs_btree_cur *cur,
501 int n,
502 struct xfs_btree_block *block)
503{
504 int level = xfs_btree_get_level(block);
505
506 ASSERT(block->bb_level != 0);
507
508 return (union xfs_btree_ptr *)
509 ((char *)block + xfs_btree_ptr_offset(cur, n, level));
510}
511
8186e517 512/*
1cb93863 513 * Get the root block which is stored in the inode.
8186e517
CH		 514 *
515 * For now this btree implementation assumes the btree root is always
516 * stored in the if_broot field of an inode fork.
517 */
518STATIC struct xfs_btree_block *
519xfs_btree_get_iroot(
520 struct xfs_btree_cur *cur)
521{
522 struct xfs_ifork *ifp;
523
524 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
525 return (struct xfs_btree_block *)ifp->if_broot;
526}
527
1da177e4
LT		 528/*
529 * Retrieve the block pointer from the cursor at the given level.
8186e517 530 * This may be an inode btree root or from a buffer.
1da177e4 531 */
8186e517 532STATIC struct xfs_btree_block * /* generic btree block pointer */
1da177e4 533xfs_btree_get_block(
8186e517 534 struct xfs_btree_cur *cur, /* btree cursor */
1da177e4 535 int level, /* level in btree */
8186e517 536 struct xfs_buf **bpp) /* buffer containing the block */
1da177e4 537{
8186e517
CH		 538 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
539 (level == cur->bc_nlevels - 1)) {
540 *bpp = NULL;
541 return xfs_btree_get_iroot(cur);
1da177e4 542 }
8186e517
CH		 543
544 *bpp = cur->bc_bufs[level];
545 return XFS_BUF_TO_BLOCK(*bpp);
1da177e4
LT		 546}
547
548/*
549 * Get a buffer for the block, return it with no data read.
550 * Long-form addressing.
551 */
552xfs_buf_t * /* buffer for fsbno */
553xfs_btree_get_bufl(
554 xfs_mount_t *mp, /* file system mount point */
555 xfs_trans_t *tp, /* transaction pointer */
556 xfs_fsblock_t fsbno, /* file system block number */
557 uint lock) /* lock flags for get_buf */
558{
559 xfs_buf_t *bp; /* buffer pointer (return value) */
560 xfs_daddr_t d; /* real disk block address */
561
562 ASSERT(fsbno != NULLFSBLOCK);
563 d = XFS_FSB_TO_DADDR(mp, fsbno);
564 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
5a52c2a5 565 ASSERT(!xfs_buf_geterror(bp));
1da177e4
LT		 566 return bp;
567}
568
569/*
570 * Get a buffer for the block, return it with no data read.
571 * Short-form addressing.
572 */
573xfs_buf_t * /* buffer for agno/agbno */
574xfs_btree_get_bufs(
575 xfs_mount_t *mp, /* file system mount point */
576 xfs_trans_t *tp, /* transaction pointer */
577 xfs_agnumber_t agno, /* allocation group number */
578 xfs_agblock_t agbno, /* allocation group block number */
579 uint lock) /* lock flags for get_buf */
580{
581 xfs_buf_t *bp; /* buffer pointer (return value) */
582 xfs_daddr_t d; /* real disk block address */
583
584 ASSERT(agno != NULLAGNUMBER);
585 ASSERT(agbno != NULLAGBLOCK);
586 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
587 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
5a52c2a5 588 ASSERT(!xfs_buf_geterror(bp));
1da177e4
LT		 589 return bp;
590}
591
1da177e4
LT		 592/*
593 * Check for the cursor referring to the last block at the given level.
594 */
595int /* 1=is last block, 0=not last block */
596xfs_btree_islastblock(
597 xfs_btree_cur_t *cur, /* btree cursor */
598 int level) /* level to check */
599{
7cc95a82 600 struct xfs_btree_block *block; /* generic btree block pointer */
1da177e4
LT		 601 xfs_buf_t *bp; /* buffer containing block */
602
603 block = xfs_btree_get_block(cur, level, &bp);
604 xfs_btree_check_block(cur, block, level, bp);
e99ab90d 605 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
69ef921b 606 return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO);
1da177e4 607 else
69ef921b 608 return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
1da177e4
LT		 609}
610
cdcf4333
CH		 611/*
612 * Change the cursor to point to the first record at the given level.
613 * Other levels are unaffected.
614 */
3cc7524c 615STATIC int /* success=1, failure=0 */
cdcf4333
CH		 616xfs_btree_firstrec(
617 xfs_btree_cur_t *cur, /* btree cursor */
618 int level) /* level to change */
619{
7cc95a82 620 struct xfs_btree_block *block; /* generic btree block pointer */
cdcf4333
CH		 621 xfs_buf_t *bp; /* buffer containing block */
622
623 /*
624 * Get the block pointer for this level.
625 */
626 block = xfs_btree_get_block(cur, level, &bp);
627 xfs_btree_check_block(cur, block, level, bp);
628 /*
629 * It's empty, there is no such record.
630 */
f2277f06 631 if (!block->bb_numrecs)
cdcf4333
CH		 632 return 0;
633 /*
634 * Set the ptr value to 1, that's the first record/key.
635 */
636 cur->bc_ptrs[level] = 1;
637 return 1;
638}
639
1da177e4
LT		 640/*
641 * Change the cursor to point to the last record in the current block
642 * at the given level. Other levels are unaffected.
643 */
3cc7524c 644STATIC int /* success=1, failure=0 */
1da177e4
LT		 645xfs_btree_lastrec(
646 xfs_btree_cur_t *cur, /* btree cursor */
647 int level) /* level to change */
648{
7cc95a82 649 struct xfs_btree_block *block; /* generic btree block pointer */
1da177e4
LT		 650 xfs_buf_t *bp; /* buffer containing block */
651
652 /*
653 * Get the block pointer for this level.
654 */
655 block = xfs_btree_get_block(cur, level, &bp);
656 xfs_btree_check_block(cur, block, level, bp);
657 /*
658 * It's empty, there is no such record.
659 */
f2277f06 660 if (!block->bb_numrecs)
1da177e4
LT		 661 return 0;
662 /*
663 * Set the ptr value to numrecs, that's the last record/key.
664 */
f2277f06 665 cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
1da177e4
LT		 666 return 1;
667}
668
669/*
670 * Compute first and last byte offsets for the fields given.
671 * Interprets the offsets table, which contains struct field offsets.
672 */
673void
674xfs_btree_offsets(
675 __int64_t fields, /* bitmask of fields */
676 const short *offsets, /* table of field offsets */
677 int nbits, /* number of bits to inspect */
678 int *first, /* output: first byte offset */
679 int *last) /* output: last byte offset */
680{
681 int i; /* current bit number */
682 __int64_t imask; /* mask for current bit number */
683
684 ASSERT(fields != 0);
685 /*
686 * Find the lowest bit, so the first byte offset.
687 */
688 for (i = 0, imask = 1LL; ; i++, imask <<= 1) {
689 if (imask & fields) {
690 *first = offsets[i];
691 break;
692 }
693 }
694 /*
695 * Find the highest bit, so the last byte offset.
696 */
697 for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) {
698 if (imask & fields) {
699 *last = offsets[i + 1] - 1;
700 break;
701 }
702 }
703}
704
705/*
706 * Get a buffer for the block, return it read in.
707 * Long-form addressing.
708 */
3d3e6f64 709int
1da177e4 710xfs_btree_read_bufl(
3d3e6f64
DC		 711 struct xfs_mount *mp, /* file system mount point */
712 struct xfs_trans *tp, /* transaction pointer */
713 xfs_fsblock_t fsbno, /* file system block number */
714 uint lock, /* lock flags for read_buf */
715 struct xfs_buf **bpp, /* buffer for fsbno */
716 int refval, /* ref count value for buffer */
1813dd64 717 const struct xfs_buf_ops *ops)
1da177e4 718{
3d3e6f64 719 struct xfs_buf *bp; /* return value */
1da177e4 720 xfs_daddr_t d; /* real disk block address */
3d3e6f64 721 int error;
1da177e4
LT		 722
723 ASSERT(fsbno != NULLFSBLOCK);
724 d = XFS_FSB_TO_DADDR(mp, fsbno);
c3f8fc73 725 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
1813dd64 726 mp->m_bsize, lock, &bp, ops);
c3f8fc73 727 if (error)
1da177e4 728 return error;
5a52c2a5 729 ASSERT(!xfs_buf_geterror(bp));
821eb21d 730 if (bp)
38f23232 731 xfs_buf_set_ref(bp, refval);
1da177e4
LT		 732 *bpp = bp;
733 return 0;
734}
735
1da177e4
LT		 736/*
737 * Read-ahead the block, don't wait for it, don't return a buffer.
738 * Long-form addressing.
739 */
740/* ARGSUSED */
741void
742xfs_btree_reada_bufl(
3d3e6f64
DC		 743 struct xfs_mount *mp, /* file system mount point */
744 xfs_fsblock_t fsbno, /* file system block number */
745 xfs_extlen_t count, /* count of filesystem blocks */
1813dd64 746 const struct xfs_buf_ops *ops)
1da177e4
LT		 747{
748 xfs_daddr_t d;
749
750 ASSERT(fsbno != NULLFSBLOCK);
751 d = XFS_FSB_TO_DADDR(mp, fsbno);
1813dd64 752 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
1da177e4
LT		 753}
754
755/*
756 * Read-ahead the block, don't wait for it, don't return a buffer.
757 * Short-form addressing.
758 */
759/* ARGSUSED */
760void
761xfs_btree_reada_bufs(
3d3e6f64
DC		 762 struct xfs_mount *mp, /* file system mount point */
763 xfs_agnumber_t agno, /* allocation group number */
764 xfs_agblock_t agbno, /* allocation group block number */
765 xfs_extlen_t count, /* count of filesystem blocks */
1813dd64 766 const struct xfs_buf_ops *ops)
1da177e4
LT		 767{
768 xfs_daddr_t d;
769
770 ASSERT(agno != NULLAGNUMBER);
771 ASSERT(agbno != NULLAGBLOCK);
772 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
1813dd64 773 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
1da177e4
LT		 774}
775
b524bfee
CH		 776STATIC int
777xfs_btree_readahead_lblock(
778 struct xfs_btree_cur *cur,
779 int lr,
780 struct xfs_btree_block *block)
781{
782 int rval = 0;
e6edbd1c
CH		 783 xfs_dfsbno_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
784 xfs_dfsbno_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
b524bfee
CH		 785
786 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLDFSBNO) {
3d3e6f64 787 xfs_btree_reada_bufl(cur->bc_mp, left, 1,
1813dd64 788 cur->bc_ops->buf_ops);
b524bfee
CH		 789 rval++;
790 }
791
792 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLDFSBNO) {
3d3e6f64 793 xfs_btree_reada_bufl(cur->bc_mp, right, 1,
1813dd64 794 cur->bc_ops->buf_ops);
b524bfee
CH		 795 rval++;
796 }
797
798 return rval;
799}
800
801STATIC int
802xfs_btree_readahead_sblock(
803 struct xfs_btree_cur *cur,
804 int lr,
805 struct xfs_btree_block *block)
806{
807 int rval = 0;
808 xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib);
809 xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib);
810
811
812 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) {
813 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
1813dd64 814 left, 1, cur->bc_ops->buf_ops);
b524bfee
CH		 815 rval++;
816 }
817
818 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) {
819 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
1813dd64 820 right, 1, cur->bc_ops->buf_ops);
b524bfee
CH		 821 rval++;
822 }
823
824 return rval;
825}
826
1da177e4
LT		 827/*
828 * Read-ahead btree blocks, at the given level.
829 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
830 */
3cc7524c 831STATIC int
b524bfee
CH		 832xfs_btree_readahead(
833 struct xfs_btree_cur *cur, /* btree cursor */
1da177e4
LT		 834 int lev, /* level in btree */
835 int lr) /* left/right bits */
836{
b524bfee
CH		 837 struct xfs_btree_block *block;
838
839 /*
840 * No readahead needed if we are at the root level and the
841 * btree root is stored in the inode.
842 */
843 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
844 (lev == cur->bc_nlevels - 1))
845 return 0;
846
847 if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
848 return 0;
1da177e4 849
1da177e4 850 cur->bc_ra[lev] |= lr;
b524bfee
CH		 851 block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
852
853 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
854 return xfs_btree_readahead_lblock(cur, lr, block);
855 return xfs_btree_readahead_sblock(cur, lr, block);
1da177e4
LT		 856}
857
21b5c978
DC		 858STATIC xfs_daddr_t
859xfs_btree_ptr_to_daddr(
860 struct xfs_btree_cur *cur,
861 union xfs_btree_ptr *ptr)
862{
863 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
864 ASSERT(ptr->l != cpu_to_be64(NULLDFSBNO));
865
866 return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
867 } else {
868 ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
869 ASSERT(ptr->s != cpu_to_be32(NULLAGBLOCK));
870
871 return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
872 be32_to_cpu(ptr->s));
873 }
874}
875
876/*
877 * Readahead @count btree blocks at the given @ptr location.
878 *
879 * We don't need to care about long or short form btrees here as we have a
880 * method of converting the ptr directly to a daddr available to us.
881 */
882STATIC void
883xfs_btree_readahead_ptr(
884 struct xfs_btree_cur *cur,
885 union xfs_btree_ptr *ptr,
886 xfs_extlen_t count)
887{
888 xfs_buf_readahead(cur->bc_mp->m_ddev_targp,
889 xfs_btree_ptr_to_daddr(cur, ptr),
890 cur->bc_mp->m_bsize * count, cur->bc_ops->buf_ops);
891}
892
1da177e4
LT		 893/*
894 * Set the buffer for level "lev" in the cursor to bp, releasing
895 * any previous buffer.
896 */
c0e59e1a 897STATIC void
1da177e4
LT		 898xfs_btree_setbuf(
899 xfs_btree_cur_t *cur, /* btree cursor */
900 int lev, /* level in btree */
901 xfs_buf_t *bp) /* new buffer to set */
902{
7cc95a82 903 struct xfs_btree_block *b; /* btree block */
1da177e4 904
c0e59e1a
CH		 905 if (cur->bc_bufs[lev])
906 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]);
1da177e4
LT		 907 cur->bc_bufs[lev] = bp;
908 cur->bc_ra[lev] = 0;
c0e59e1a 909
1da177e4 910 b = XFS_BUF_TO_BLOCK(bp);
e99ab90d 911 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
69ef921b 912 if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLDFSBNO))
1da177e4 913 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
69ef921b 914 if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO))
1da177e4
LT		 915 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
916 } else {
69ef921b 917 if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK))
1da177e4 918 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
69ef921b 919 if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK))
1da177e4
LT		 920 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
921 }
922}
637aa50f
CH		 923
924STATIC int
925xfs_btree_ptr_is_null(
926 struct xfs_btree_cur *cur,
927 union xfs_btree_ptr *ptr)
928{
929 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
69ef921b 930 return ptr->l == cpu_to_be64(NULLDFSBNO);
637aa50f 931 else
69ef921b 932 return ptr->s == cpu_to_be32(NULLAGBLOCK);
637aa50f
CH		 933}
934
4b22a571
CH		 935STATIC void
936xfs_btree_set_ptr_null(
937 struct xfs_btree_cur *cur,
938 union xfs_btree_ptr *ptr)
939{
940 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
33ad965d 941 ptr->l = cpu_to_be64(NULLDFSBNO);
4b22a571
CH		 942 else
943 ptr->s = cpu_to_be32(NULLAGBLOCK);
944}
945
637aa50f
CH		 946/*
947 * Get/set/init sibling pointers
948 */
949STATIC void
950xfs_btree_get_sibling(
951 struct xfs_btree_cur *cur,
952 struct xfs_btree_block *block,
953 union xfs_btree_ptr *ptr,
954 int lr)
955{
956 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
957
958 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
959 if (lr == XFS_BB_RIGHTSIB)
960 ptr->l = block->bb_u.l.bb_rightsib;
961 else
962 ptr->l = block->bb_u.l.bb_leftsib;
963 } else {
964 if (lr == XFS_BB_RIGHTSIB)
965 ptr->s = block->bb_u.s.bb_rightsib;
966 else
967 ptr->s = block->bb_u.s.bb_leftsib;
968 }
969}
970
f5eb8e7c
CH		 971STATIC void
972xfs_btree_set_sibling(
973 struct xfs_btree_cur *cur,
974 struct xfs_btree_block *block,
975 union xfs_btree_ptr *ptr,
976 int lr)
977{
978 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
979
980 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
981 if (lr == XFS_BB_RIGHTSIB)
982 block->bb_u.l.bb_rightsib = ptr->l;
983 else
984 block->bb_u.l.bb_leftsib = ptr->l;
985 } else {
986 if (lr == XFS_BB_RIGHTSIB)
987 block->bb_u.s.bb_rightsib = ptr->s;
988 else
989 block->bb_u.s.bb_leftsib = ptr->s;
990 }
991}
992
ee1a47ab
CH		 993void
994xfs_btree_init_block_int(
995 struct xfs_mount *mp,
996 struct xfs_btree_block *buf,
997 xfs_daddr_t blkno,
998 __u32 magic,
999 __u16 level,
1000 __u16 numrecs,
1001 __u64 owner,
1002 unsigned int flags)
1003{
1004 buf->bb_magic = cpu_to_be32(magic);
1005 buf->bb_level = cpu_to_be16(level);
1006 buf->bb_numrecs = cpu_to_be16(numrecs);
1007
1008 if (flags & XFS_BTREE_LONG_PTRS) {
1009 buf->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO);
1010 buf->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO);
1011 if (flags & XFS_BTREE_CRC_BLOCKS) {
1012 buf->bb_u.l.bb_blkno = cpu_to_be64(blkno);
1013 buf->bb_u.l.bb_owner = cpu_to_be64(owner);
1014 uuid_copy(&buf->bb_u.l.bb_uuid, &mp->m_sb.sb_uuid);
1015 buf->bb_u.l.bb_pad = 0;
b58fa554 1016 buf->bb_u.l.bb_lsn = 0;
ee1a47ab
CH		 1017 }
1018 } else {
1019 /* owner is a 32 bit value on short blocks */
1020 __u32 __owner = (__u32)owner;
1021
1022 buf->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
1023 buf->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
1024 if (flags & XFS_BTREE_CRC_BLOCKS) {
1025 buf->bb_u.s.bb_blkno = cpu_to_be64(blkno);
1026 buf->bb_u.s.bb_owner = cpu_to_be32(__owner);
1027 uuid_copy(&buf->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid);
b58fa554 1028 buf->bb_u.s.bb_lsn = 0;
ee1a47ab
CH		 1029 }
1030 }
1031}
1032
b64f3a39 1033void
f5eb8e7c 1034xfs_btree_init_block(
b64f3a39
DC		 1035 struct xfs_mount *mp,
1036 struct xfs_buf *bp,
1037 __u32 magic,
1038 __u16 level,
1039 __u16 numrecs,
ee1a47ab 1040 __u64 owner,
b64f3a39 1041 unsigned int flags)
f5eb8e7c 1042{
ee1a47ab
CH		 1043 xfs_btree_init_block_int(mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1044 magic, level, numrecs, owner, flags);
f5eb8e7c
CH		 1045}
1046
b64f3a39
DC		 1047STATIC void
1048xfs_btree_init_block_cur(
1049 struct xfs_btree_cur *cur,
ee1a47ab 1050 struct xfs_buf *bp,
b64f3a39 1051 int level,
ee1a47ab 1052 int numrecs)
b64f3a39 1053{
ee1a47ab
CH		 1054 __u64 owner;
1055
1056 /*
1057 * we can pull the owner from the cursor right now as the different
1058 * owners align directly with the pointer size of the btree. This may
1059 * change in future, but is safe for current users of the generic btree
1060 * code.
1061 */
1062 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1063 owner = cur->bc_private.b.ip->i_ino;
1064 else
1065 owner = cur->bc_private.a.agno;
1066
1067 xfs_btree_init_block_int(cur->bc_mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1068 xfs_btree_magic(cur), level, numrecs,
1069 owner, cur->bc_flags);
b64f3a39
DC		 1070}
1071
278d0ca1
CH		 1072/*
1073 * Return true if ptr is the last record in the btree and
ee1a47ab 1074 * we need to track updates to this record. The decision
278d0ca1
CH		 1075 * will be further refined in the update_lastrec method.
1076 */
1077STATIC int
1078xfs_btree_is_lastrec(
1079 struct xfs_btree_cur *cur,
1080 struct xfs_btree_block *block,
1081 int level)
1082{
1083 union xfs_btree_ptr ptr;
1084
1085 if (level > 0)
1086 return 0;
1087 if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
1088 return 0;
1089
1090 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1091 if (!xfs_btree_ptr_is_null(cur, &ptr))
1092 return 0;
1093 return 1;
1094}
1095
f5eb8e7c
CH		 1096STATIC void
1097xfs_btree_buf_to_ptr(
1098 struct xfs_btree_cur *cur,
1099 struct xfs_buf *bp,
1100 union xfs_btree_ptr *ptr)
1101{
1102 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1103 ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
1104 XFS_BUF_ADDR(bp)));
1105 else {
9d87c319 1106 ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp,
f5eb8e7c
CH		 1107 XFS_BUF_ADDR(bp)));
1108 }
1109}
1110
637aa50f
CH		 1111STATIC void
1112xfs_btree_set_refs(
1113 struct xfs_btree_cur *cur,
1114 struct xfs_buf *bp)
1115{
1116 switch (cur->bc_btnum) {
1117 case XFS_BTNUM_BNO:
1118 case XFS_BTNUM_CNT:
38f23232 1119 xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF);
637aa50f
CH		 1120 break;
1121 case XFS_BTNUM_INO:
38f23232 1122 xfs_buf_set_ref(bp, XFS_INO_BTREE_REF);
637aa50f
CH		 1123 break;
1124 case XFS_BTNUM_BMAP:
38f23232 1125 xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF);
637aa50f
CH		 1126 break;
1127 default:
1128 ASSERT(0);
1129 }
1130}
1131
f5eb8e7c
CH		 1132STATIC int
1133xfs_btree_get_buf_block(
1134 struct xfs_btree_cur *cur,
1135 union xfs_btree_ptr *ptr,
1136 int flags,
1137 struct xfs_btree_block **block,
1138 struct xfs_buf **bpp)
1139{
1140 struct xfs_mount *mp = cur->bc_mp;
1141 xfs_daddr_t d;
1142
1143 /* need to sort out how callers deal with failures first */
0cadda1c 1144 ASSERT(!(flags & XBF_TRYLOCK));
f5eb8e7c
CH		 1145
1146 d = xfs_btree_ptr_to_daddr(cur, ptr);
1147 *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
1148 mp->m_bsize, flags);
1149
2a30f36d
CS		 1150 if (!*bpp)
1151 return ENOMEM;
f5eb8e7c 1152
1813dd64 1153 (*bpp)->b_ops = cur->bc_ops->buf_ops;
f5eb8e7c
CH		 1154 *block = XFS_BUF_TO_BLOCK(*bpp);
1155 return 0;
1156}
1157
637aa50f
CH		 1158/*
1159 * Read in the buffer at the given ptr and return the buffer and
1160 * the block pointer within the buffer.
1161 */
1162STATIC int
1163xfs_btree_read_buf_block(
1164 struct xfs_btree_cur *cur,
1165 union xfs_btree_ptr *ptr,
1166 int level,
1167 int flags,
1168 struct xfs_btree_block **block,
1169 struct xfs_buf **bpp)
1170{
1171 struct xfs_mount *mp = cur->bc_mp;
1172 xfs_daddr_t d;
1173 int error;
1174
1175 /* need to sort out how callers deal with failures first */
0cadda1c 1176 ASSERT(!(flags & XBF_TRYLOCK));
637aa50f
CH		 1177
1178 d = xfs_btree_ptr_to_daddr(cur, ptr);
1179 error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
3d3e6f64 1180 mp->m_bsize, flags, bpp,
1813dd64 1181 cur->bc_ops->buf_ops);
637aa50f
CH		 1182 if (error)
1183 return error;
1184
5a52c2a5 1185 ASSERT(!xfs_buf_geterror(*bpp));
637aa50f
CH		 1186 xfs_btree_set_refs(cur, *bpp);
1187 *block = XFS_BUF_TO_BLOCK(*bpp);
3d3e6f64 1188 return 0;
637aa50f
CH		 1189}
1190
38bb7423
CH		 1191/*
1192 * Copy keys from one btree block to another.
1193 */
1194STATIC void
1195xfs_btree_copy_keys(
1196 struct xfs_btree_cur *cur,
1197 union xfs_btree_key *dst_key,
1198 union xfs_btree_key *src_key,
1199 int numkeys)
1200{
1201 ASSERT(numkeys >= 0);
1202 memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
1203}
1204
278d0ca1
CH		 1205/*
1206 * Copy records from one btree block to another.
1207 */
1208STATIC void
1209xfs_btree_copy_recs(
1210 struct xfs_btree_cur *cur,
1211 union xfs_btree_rec *dst_rec,
1212 union xfs_btree_rec *src_rec,
1213 int numrecs)
1214{
1215 ASSERT(numrecs >= 0);
1216 memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
1217}
1218
9eaead51
CH		 1219/*
1220 * Copy block pointers from one btree block to another.
1221 */
1222STATIC void
1223xfs_btree_copy_ptrs(
1224 struct xfs_btree_cur *cur,
1225 union xfs_btree_ptr *dst_ptr,
1226 union xfs_btree_ptr *src_ptr,
1227 int numptrs)
1228{
1229 ASSERT(numptrs >= 0);
1230 memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
1231}
1232
1233/*
1234 * Shift keys one index left/right inside a single btree block.
1235 */
1236STATIC void
1237xfs_btree_shift_keys(
1238 struct xfs_btree_cur *cur,
1239 union xfs_btree_key *key,
1240 int dir,
1241 int numkeys)
1242{
1243 char *dst_key;
1244
1245 ASSERT(numkeys >= 0);
1246 ASSERT(dir == 1 || dir == -1);
1247
1248 dst_key = (char *)key + (dir * cur->bc_ops->key_len);
1249 memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
1250}
1251
1252/*
1253 * Shift records one index left/right inside a single btree block.
1254 */
1255STATIC void
1256xfs_btree_shift_recs(
1257 struct xfs_btree_cur *cur,
1258 union xfs_btree_rec *rec,
1259 int dir,
1260 int numrecs)
1261{
1262 char *dst_rec;
1263
1264 ASSERT(numrecs >= 0);
1265 ASSERT(dir == 1 || dir == -1);
1266
1267 dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
1268 memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
1269}
1270
1271/*
1272 * Shift block pointers one index left/right inside a single btree block.
1273 */
1274STATIC void
1275xfs_btree_shift_ptrs(
1276 struct xfs_btree_cur *cur,
1277 union xfs_btree_ptr *ptr,
1278 int dir,
1279 int numptrs)
1280{
1281 char *dst_ptr;
1282
1283 ASSERT(numptrs >= 0);
1284 ASSERT(dir == 1 || dir == -1);
1285
1286 dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
1287 memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
1288}
1289
38bb7423
CH		 1290/*
1291 * Log key values from the btree block.
1292 */
1293STATIC void
1294xfs_btree_log_keys(
1295 struct xfs_btree_cur *cur,
1296 struct xfs_buf *bp,
1297 int first,
1298 int last)
1299{
1300 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1301 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1302
1303 if (bp) {
61fe135c 1304 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
38bb7423
CH		 1305 xfs_trans_log_buf(cur->bc_tp, bp,
1306 xfs_btree_key_offset(cur, first),
1307 xfs_btree_key_offset(cur, last + 1) - 1);
1308 } else {
1309 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1310 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1311 }
1312
1313 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1314}
1315
278d0ca1
CH		 1316/*
1317 * Log record values from the btree block.
1318 */
fd6bcc5b 1319void
278d0ca1
CH		 1320xfs_btree_log_recs(
1321 struct xfs_btree_cur *cur,
1322 struct xfs_buf *bp,
1323 int first,
1324 int last)
1325{
1326 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1327 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1328
61fe135c 1329 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
278d0ca1
CH		 1330 xfs_trans_log_buf(cur->bc_tp, bp,
1331 xfs_btree_rec_offset(cur, first),
1332 xfs_btree_rec_offset(cur, last + 1) - 1);
1333
1334 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1335}
1336
9eaead51
CH		 1337/*
1338 * Log block pointer fields from a btree block (nonleaf).
1339 */
1340STATIC void
1341xfs_btree_log_ptrs(
1342 struct xfs_btree_cur *cur, /* btree cursor */
1343 struct xfs_buf *bp, /* buffer containing btree block */
1344 int first, /* index of first pointer to log */
1345 int last) /* index of last pointer to log */
1346{
1347 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1348 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1349
1350 if (bp) {
1351 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
1352 int level = xfs_btree_get_level(block);
1353
61fe135c 1354 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
9eaead51
CH		 1355 xfs_trans_log_buf(cur->bc_tp, bp,
1356 xfs_btree_ptr_offset(cur, first, level),
1357 xfs_btree_ptr_offset(cur, last + 1, level) - 1);
1358 } else {
1359 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1360 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1361 }
1362
1363 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1364}
1365
1366/*
1367 * Log fields from a btree block header.
1368 */
fd6bcc5b 1369void
9eaead51
CH		 1370xfs_btree_log_block(
1371 struct xfs_btree_cur *cur, /* btree cursor */
1372 struct xfs_buf *bp, /* buffer containing btree block */
1373 int fields) /* mask of fields: XFS_BB_... */
1374{
1375 int first; /* first byte offset logged */
1376 int last; /* last byte offset logged */
1377 static const short soffsets[] = { /* table of offsets (short) */
7cc95a82
CH		 1378 offsetof(struct xfs_btree_block, bb_magic),
1379 offsetof(struct xfs_btree_block, bb_level),
1380 offsetof(struct xfs_btree_block, bb_numrecs),
1381 offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
1382 offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
ee1a47ab
CH		 1383 offsetof(struct xfs_btree_block, bb_u.s.bb_blkno),
1384 offsetof(struct xfs_btree_block, bb_u.s.bb_lsn),
1385 offsetof(struct xfs_btree_block, bb_u.s.bb_uuid),
1386 offsetof(struct xfs_btree_block, bb_u.s.bb_owner),
1387 offsetof(struct xfs_btree_block, bb_u.s.bb_crc),
1388 XFS_BTREE_SBLOCK_CRC_LEN
9eaead51
CH		 1389 };
1390 static const short loffsets[] = { /* table of offsets (long) */
7cc95a82
CH		 1391 offsetof(struct xfs_btree_block, bb_magic),
1392 offsetof(struct xfs_btree_block, bb_level),
1393 offsetof(struct xfs_btree_block, bb_numrecs),
1394 offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
1395 offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
ee1a47ab
CH		 1396 offsetof(struct xfs_btree_block, bb_u.l.bb_blkno),
1397 offsetof(struct xfs_btree_block, bb_u.l.bb_lsn),
1398 offsetof(struct xfs_btree_block, bb_u.l.bb_uuid),
1399 offsetof(struct xfs_btree_block, bb_u.l.bb_owner),
1400 offsetof(struct xfs_btree_block, bb_u.l.bb_crc),
1401 offsetof(struct xfs_btree_block, bb_u.l.bb_pad),
1402 XFS_BTREE_LBLOCK_CRC_LEN
9eaead51
CH		 1403 };
1404
1405 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1406 XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
1407
1408 if (bp) {
ee1a47ab
CH		 1409 int nbits;
1410
1411 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
1412 /*
1413 * We don't log the CRC when updating a btree
1414 * block but instead recreate it during log
1415 * recovery. As the log buffers have checksums
1416 * of their own this is safe and avoids logging a crc
1417 * update in a lot of places.
1418 */
1419 if (fields == XFS_BB_ALL_BITS)
1420 fields = XFS_BB_ALL_BITS_CRC;
1421 nbits = XFS_BB_NUM_BITS_CRC;
1422 } else {
1423 nbits = XFS_BB_NUM_BITS;
1424 }
9eaead51
CH		 1425 xfs_btree_offsets(fields,
1426 (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
1427 loffsets : soffsets,
ee1a47ab 1428 nbits, &first, &last);
61fe135c 1429 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
9eaead51
CH		 1430 xfs_trans_log_buf(cur->bc_tp, bp, first, last);
1431 } else {
1432 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1433 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1434 }
1435
1436 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1437}
1438
637aa50f
CH		 1439/*
1440 * Increment cursor by one record at the level.
1441 * For nonzero levels the leaf-ward information is untouched.
1442 */
1443int /* error */
1444xfs_btree_increment(
1445 struct xfs_btree_cur *cur,
1446 int level,
1447 int *stat) /* success/failure */
1448{
1449 struct xfs_btree_block *block;
1450 union xfs_btree_ptr ptr;
1451 struct xfs_buf *bp;
1452 int error; /* error return value */
1453 int lev;
1454
1455 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1456 XFS_BTREE_TRACE_ARGI(cur, level);
1457
1458 ASSERT(level < cur->bc_nlevels);
1459
1460 /* Read-ahead to the right at this level. */
1461 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
1462
1463 /* Get a pointer to the btree block. */
1464 block = xfs_btree_get_block(cur, level, &bp);
1465
1466#ifdef DEBUG
1467 error = xfs_btree_check_block(cur, block, level, bp);
1468 if (error)
1469 goto error0;
1470#endif
1471
1472 /* We're done if we remain in the block after the increment. */
1473 if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
1474 goto out1;
1475
1476 /* Fail if we just went off the right edge of the tree. */
1477 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1478 if (xfs_btree_ptr_is_null(cur, &ptr))
1479 goto out0;
1480
1481 XFS_BTREE_STATS_INC(cur, increment);
1482
1483 /*
1484 * March up the tree incrementing pointers.
1485 * Stop when we don't go off the right edge of a block.
1486 */
1487 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1488 block = xfs_btree_get_block(cur, lev, &bp);
1489
1490#ifdef DEBUG
1491 error = xfs_btree_check_block(cur, block, lev, bp);
1492 if (error)
1493 goto error0;
1494#endif
1495
1496 if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
1497 break;
1498
1499 /* Read-ahead the right block for the next loop. */
1500 xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
1501 }
1502
1503 /*
1504 * If we went off the root then we are either seriously
1505 * confused or have the tree root in an inode.
1506 */
1507 if (lev == cur->bc_nlevels) {
1508 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1509 goto out0;
1510 ASSERT(0);
1511 error = EFSCORRUPTED;
1512 goto error0;
1513 }
1514 ASSERT(lev < cur->bc_nlevels);
1515
1516 /*
1517 * Now walk back down the tree, fixing up the cursor's buffer
1518 * pointers and key numbers.
1519 */
1520 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1521 union xfs_btree_ptr *ptrp;
1522
1523 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1524 error = xfs_btree_read_buf_block(cur, ptrp, --lev,
1525 0, &block, &bp);
1526 if (error)
1527 goto error0;
1528
1529 xfs_btree_setbuf(cur, lev, bp);
1530 cur->bc_ptrs[lev] = 1;
1531 }
1532out1:
1533 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1534 *stat = 1;
1535 return 0;
1536
1537out0:
1538 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1539 *stat = 0;
1540 return 0;
1541
1542error0:
1543 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1544 return error;
1545}
8df4da4a
CH		 1546
1547/*
1548 * Decrement cursor by one record at the level.
1549 * For nonzero levels the leaf-ward information is untouched.
1550 */
1551int /* error */
1552xfs_btree_decrement(
1553 struct xfs_btree_cur *cur,
1554 int level,
1555 int *stat) /* success/failure */
1556{
1557 struct xfs_btree_block *block;
1558 xfs_buf_t *bp;
1559 int error; /* error return value */
1560 int lev;
1561 union xfs_btree_ptr ptr;
1562
1563 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1564 XFS_BTREE_TRACE_ARGI(cur, level);
1565
1566 ASSERT(level < cur->bc_nlevels);
1567
1568 /* Read-ahead to the left at this level. */
1569 xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
1570
1571 /* We're done if we remain in the block after the decrement. */
1572 if (--cur->bc_ptrs[level] > 0)
1573 goto out1;
1574
1575 /* Get a pointer to the btree block. */
1576 block = xfs_btree_get_block(cur, level, &bp);
1577
1578#ifdef DEBUG
1579 error = xfs_btree_check_block(cur, block, level, bp);
1580 if (error)
1581 goto error0;
1582#endif
1583
1584 /* Fail if we just went off the left edge of the tree. */
1585 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
1586 if (xfs_btree_ptr_is_null(cur, &ptr))
1587 goto out0;
1588
1589 XFS_BTREE_STATS_INC(cur, decrement);
1590
1591 /*
1592 * March up the tree decrementing pointers.
1593 * Stop when we don't go off the left edge of a block.
1594 */
1595 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1596 if (--cur->bc_ptrs[lev] > 0)
1597 break;
1598 /* Read-ahead the left block for the next loop. */
1599 xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
1600 }
1601
1602 /*
1603 * If we went off the root then we are seriously confused.
1604 * or the root of the tree is in an inode.
1605 */
1606 if (lev == cur->bc_nlevels) {
1607 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1608 goto out0;
1609 ASSERT(0);
1610 error = EFSCORRUPTED;
1611 goto error0;
1612 }
1613 ASSERT(lev < cur->bc_nlevels);
1614
1615 /*
1616 * Now walk back down the tree, fixing up the cursor's buffer
1617 * pointers and key numbers.
1618 */
1619 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1620 union xfs_btree_ptr *ptrp;
1621
1622 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1623 error = xfs_btree_read_buf_block(cur, ptrp, --lev,
1624 0, &block, &bp);
1625 if (error)
1626 goto error0;
1627 xfs_btree_setbuf(cur, lev, bp);
1628 cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
1629 }
1630out1:
1631 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1632 *stat = 1;
1633 return 0;
1634
1635out0:
1636 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1637 *stat = 0;
1638 return 0;
1639
1640error0:
1641 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1642 return error;
1643}
1644
fe033cc8
CH		 1645STATIC int
1646xfs_btree_lookup_get_block(
1647 struct xfs_btree_cur *cur, /* btree cursor */
1648 int level, /* level in the btree */
1649 union xfs_btree_ptr *pp, /* ptr to btree block */
1650 struct xfs_btree_block **blkp) /* return btree block */
1651{
1652 struct xfs_buf *bp; /* buffer pointer for btree block */
1653 int error = 0;
1654
1655 /* special case the root block if in an inode */
1656 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1657 (level == cur->bc_nlevels - 1)) {
1658 *blkp = xfs_btree_get_iroot(cur);
1659 return 0;
1660 }
1661
1662 /*
1663 * If the old buffer at this level for the disk address we are
1664 * looking for re-use it.
1665 *
1666 * Otherwise throw it away and get a new one.
1667 */
1668 bp = cur->bc_bufs[level];
1669 if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
1670 *blkp = XFS_BUF_TO_BLOCK(bp);
1671 return 0;
1672 }
1673
1674 error = xfs_btree_read_buf_block(cur, pp, level, 0, blkp, &bp);
1675 if (error)
1676 return error;
1677
1678 xfs_btree_setbuf(cur, level, bp);
1679 return 0;
1680}
1681
1682/*
1683 * Get current search key. For level 0 we don't actually have a key
1684 * structure so we make one up from the record. For all other levels
1685 * we just return the right key.
1686 */
1687STATIC union xfs_btree_key *
1688xfs_lookup_get_search_key(
1689 struct xfs_btree_cur *cur,
1690 int level,
1691 int keyno,
1692 struct xfs_btree_block *block,
1693 union xfs_btree_key *kp)
1694{
1695 if (level == 0) {
1696 cur->bc_ops->init_key_from_rec(kp,
1697 xfs_btree_rec_addr(cur, keyno, block));
1698 return kp;
1699 }
1700
1701 return xfs_btree_key_addr(cur, keyno, block);
1702}
1703
1704/*
1705 * Lookup the record. The cursor is made to point to it, based on dir.
49d3da14 1706 * stat is set to 0 if can't find any such record, 1 for success.
fe033cc8
CH		 1707 */
1708int /* error */
1709xfs_btree_lookup(
1710 struct xfs_btree_cur *cur, /* btree cursor */
1711 xfs_lookup_t dir, /* <=, ==, or >= */
1712 int *stat) /* success/failure */
1713{
1714 struct xfs_btree_block *block; /* current btree block */
1715 __int64_t diff; /* difference for the current key */
1716 int error; /* error return value */
1717 int keyno; /* current key number */
1718 int level; /* level in the btree */
1719 union xfs_btree_ptr *pp; /* ptr to btree block */
1720 union xfs_btree_ptr ptr; /* ptr to btree block */
1721
1722 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1723 XFS_BTREE_TRACE_ARGI(cur, dir);
1724
1725 XFS_BTREE_STATS_INC(cur, lookup);
1726
1727 block = NULL;
1728 keyno = 0;
1729
1730 /* initialise start pointer from cursor */
1731 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
1732 pp = &ptr;
1733
1734 /*
1735 * Iterate over each level in the btree, starting at the root.
1736 * For each level above the leaves, find the key we need, based
1737 * on the lookup record, then follow the corresponding block
1738 * pointer down to the next level.
1739 */
1740 for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
1741 /* Get the block we need to do the lookup on. */
1742 error = xfs_btree_lookup_get_block(cur, level, pp, &block);
1743 if (error)
1744 goto error0;
1745
1746 if (diff == 0) {
1747 /*
1748 * If we already had a key match at a higher level, we
1749 * know we need to use the first entry in this block.
1750 */
1751 keyno = 1;
1752 } else {
1753 /* Otherwise search this block. Do a binary search. */
1754
1755 int high; /* high entry number */
1756 int low; /* low entry number */
1757
1758 /* Set low and high entry numbers, 1-based. */
1759 low = 1;
1760 high = xfs_btree_get_numrecs(block);
1761 if (!high) {
1762 /* Block is empty, must be an empty leaf. */
1763 ASSERT(level == 0 && cur->bc_nlevels == 1);
1764
1765 cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
1766 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1767 *stat = 0;
1768 return 0;
1769 }
1770
1771 /* Binary search the block. */
1772 while (low <= high) {
1773 union xfs_btree_key key;
1774 union xfs_btree_key *kp;
1775
1776 XFS_BTREE_STATS_INC(cur, compare);
1777
1778 /* keyno is average of low and high. */
1779 keyno = (low + high) >> 1;
1780
1781 /* Get current search key */
1782 kp = xfs_lookup_get_search_key(cur, level,
1783 keyno, block, &key);
1784
1785 /*
1786 * Compute difference to get next direction:
1787 * - less than, move right
1788 * - greater than, move left
1789 * - equal, we're done
1790 */
1791 diff = cur->bc_ops->key_diff(cur, kp);
1792 if (diff < 0)
1793 low = keyno + 1;
1794 else if (diff > 0)
1795 high = keyno - 1;
1796 else
1797 break;
1798 }
1799 }
1800
1801 /*
1802 * If there are more levels, set up for the next level
1803 * by getting the block number and filling in the cursor.
1804 */
1805 if (level > 0) {
1806 /*
1807 * If we moved left, need the previous key number,
1808 * unless there isn't one.
1809 */
1810 if (diff > 0 && --keyno < 1)
1811 keyno = 1;
1812 pp = xfs_btree_ptr_addr(cur, keyno, block);
1813
1814#ifdef DEBUG
1815 error = xfs_btree_check_ptr(cur, pp, 0, level);
1816 if (error)
1817 goto error0;
1818#endif
1819 cur->bc_ptrs[level] = keyno;
1820 }
1821 }
1822
1823 /* Done with the search. See if we need to adjust the results. */
1824 if (dir != XFS_LOOKUP_LE && diff < 0) {
1825 keyno++;
1826 /*
1827 * If ge search and we went off the end of the block, but it's
1828 * not the last block, we're in the wrong block.
1829 */
1830 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1831 if (dir == XFS_LOOKUP_GE &&
1832 keyno > xfs_btree_get_numrecs(block) &&
1833 !xfs_btree_ptr_is_null(cur, &ptr)) {
1834 int i;
1835
1836 cur->bc_ptrs[0] = keyno;
1837 error = xfs_btree_increment(cur, 0, &i);
1838 if (error)
1839 goto error0;
1840 XFS_WANT_CORRUPTED_RETURN(i == 1);
1841 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1842 *stat = 1;
1843 return 0;
1844 }
1845 } else if (dir == XFS_LOOKUP_LE && diff > 0)
1846 keyno--;
1847 cur->bc_ptrs[0] = keyno;
1848
1849 /* Return if we succeeded or not. */
1850 if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
1851 *stat = 0;
1852 else if (dir != XFS_LOOKUP_EQ || diff == 0)
1853 *stat = 1;
1854 else
1855 *stat = 0;
1856 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1857 return 0;
1858
1859error0:
1860 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1861 return error;
1862}
38bb7423
CH		 1863
1864/*
1865 * Update keys at all levels from here to the root along the cursor's path.
1866 */
3cc7524c 1867STATIC int
38bb7423
CH		 1868xfs_btree_updkey(
1869 struct xfs_btree_cur *cur,
1870 union xfs_btree_key *keyp,
1871 int level)
1872{
1873 struct xfs_btree_block *block;
1874 struct xfs_buf *bp;
1875 union xfs_btree_key *kp;
1876 int ptr;
1877
1878 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1879 XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
1880
1881 ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1);
1882
1883 /*
1884 * Go up the tree from this level toward the root.
1885 * At each level, update the key value to the value input.
1886 * Stop when we reach a level where the cursor isn't pointing
1887 * at the first entry in the block.
1888 */
1889 for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
1890#ifdef DEBUG
1891 int error;
1892#endif
1893 block = xfs_btree_get_block(cur, level, &bp);
1894#ifdef DEBUG
1895 error = xfs_btree_check_block(cur, block, level, bp);
1896 if (error) {
1897 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1898 return error;
1899 }
1900#endif
1901 ptr = cur->bc_ptrs[level];
1902 kp = xfs_btree_key_addr(cur, ptr, block);
1903 xfs_btree_copy_keys(cur, kp, keyp, 1);
1904 xfs_btree_log_keys(cur, bp, ptr, ptr);
1905 }
1906
1907 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1908 return 0;
1909}
278d0ca1
CH		 1910
1911/*
1912 * Update the record referred to by cur to the value in the
1913 * given record. This either works (return 0) or gets an
1914 * EFSCORRUPTED error.
1915 */
1916int
1917xfs_btree_update(
1918 struct xfs_btree_cur *cur,
1919 union xfs_btree_rec *rec)
1920{
1921 struct xfs_btree_block *block;
1922 struct xfs_buf *bp;
1923 int error;
1924 int ptr;
1925 union xfs_btree_rec *rp;
1926
1927 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1928 XFS_BTREE_TRACE_ARGR(cur, rec);
1929
1930 /* Pick up the current block. */
1931 block = xfs_btree_get_block(cur, 0, &bp);
1932
1933#ifdef DEBUG
1934 error = xfs_btree_check_block(cur, block, 0, bp);
1935 if (error)
1936 goto error0;
1937#endif
1938 /* Get the address of the rec to be updated. */
1939 ptr = cur->bc_ptrs[0];
1940 rp = xfs_btree_rec_addr(cur, ptr, block);
1941
1942 /* Fill in the new contents and log them. */
1943 xfs_btree_copy_recs(cur, rp, rec, 1);
1944 xfs_btree_log_recs(cur, bp, ptr, ptr);
1945
1946 /*
1947 * If we are tracking the last record in the tree and
1948 * we are at the far right edge of the tree, update it.
1949 */
1950 if (xfs_btree_is_lastrec(cur, block, 0)) {
1951 cur->bc_ops->update_lastrec(cur, block, rec,
1952 ptr, LASTREC_UPDATE);
1953 }
1954
1955 /* Updating first rec in leaf. Pass new key value up to our parent. */
1956 if (ptr == 1) {
1957 union xfs_btree_key key;
1958
1959 cur->bc_ops->init_key_from_rec(&key, rec);
1960 error = xfs_btree_updkey(cur, &key, 1);
1961 if (error)
1962 goto error0;
1963 }
1964
1965 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1966 return 0;
1967
1968error0:
1969 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1970 return error;
1971}
1972
687b890a
CH		 1973/*
1974 * Move 1 record left from cur/level if possible.
1975 * Update cur to reflect the new path.
1976 */
3cc7524c 1977STATIC int /* error */
687b890a
CH		 1978xfs_btree_lshift(
1979 struct xfs_btree_cur *cur,
1980 int level,
1981 int *stat) /* success/failure */
1982{
1983 union xfs_btree_key key; /* btree key */
1984 struct xfs_buf *lbp; /* left buffer pointer */
1985 struct xfs_btree_block *left; /* left btree block */
1986 int lrecs; /* left record count */
1987 struct xfs_buf *rbp; /* right buffer pointer */
1988 struct xfs_btree_block *right; /* right btree block */
1989 int rrecs; /* right record count */
1990 union xfs_btree_ptr lptr; /* left btree pointer */
1991 union xfs_btree_key *rkp = NULL; /* right btree key */
1992 union xfs_btree_ptr *rpp = NULL; /* right address pointer */
1993 union xfs_btree_rec *rrp = NULL; /* right record pointer */
1994 int error; /* error return value */
1995
1996 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1997 XFS_BTREE_TRACE_ARGI(cur, level);
1998
1999 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2000 level == cur->bc_nlevels - 1)
2001 goto out0;
2002
2003 /* Set up variables for this block as "right". */
2004 right = xfs_btree_get_block(cur, level, &rbp);
2005
2006#ifdef DEBUG
2007 error = xfs_btree_check_block(cur, right, level, rbp);
2008 if (error)
2009 goto error0;
2010#endif
2011
2012 /* If we've got no left sibling then we can't shift an entry left. */
2013 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2014 if (xfs_btree_ptr_is_null(cur, &lptr))
2015 goto out0;
2016
2017 /*
2018 * If the cursor entry is the one that would be moved, don't
2019 * do it... it's too complicated.
2020 */
2021 if (cur->bc_ptrs[level] <= 1)
2022 goto out0;
2023
2024 /* Set up the left neighbor as "left". */
2025 error = xfs_btree_read_buf_block(cur, &lptr, level, 0, &left, &lbp);
2026 if (error)
2027 goto error0;
2028
2029 /* If it's full, it can't take another entry. */
2030 lrecs = xfs_btree_get_numrecs(left);
2031 if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
2032 goto out0;
2033
2034 rrecs = xfs_btree_get_numrecs(right);
2035
2036 /*
2037 * We add one entry to the left side and remove one for the right side.
9da096fd 2038 * Account for it here, the changes will be updated on disk and logged
687b890a
CH		 2039 * later.
2040 */
2041 lrecs++;
2042 rrecs--;
2043
2044 XFS_BTREE_STATS_INC(cur, lshift);
2045 XFS_BTREE_STATS_ADD(cur, moves, 1);
2046
2047 /*
2048 * If non-leaf, copy a key and a ptr to the left block.
2049 * Log the changes to the left block.
2050 */
2051 if (level > 0) {
2052 /* It's a non-leaf. Move keys and pointers. */
2053 union xfs_btree_key *lkp; /* left btree key */
2054 union xfs_btree_ptr *lpp; /* left address pointer */
2055
2056 lkp = xfs_btree_key_addr(cur, lrecs, left);
2057 rkp = xfs_btree_key_addr(cur, 1, right);
2058
2059 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2060 rpp = xfs_btree_ptr_addr(cur, 1, right);
2061#ifdef DEBUG
2062 error = xfs_btree_check_ptr(cur, rpp, 0, level);
2063 if (error)
2064 goto error0;
2065#endif
2066 xfs_btree_copy_keys(cur, lkp, rkp, 1);
2067 xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
2068
2069 xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
2070 xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
2071
4a26e66e
CH		 2072 ASSERT(cur->bc_ops->keys_inorder(cur,
2073 xfs_btree_key_addr(cur, lrecs - 1, left), lkp));
687b890a
CH		 2074 } else {
2075 /* It's a leaf. Move records. */
2076 union xfs_btree_rec *lrp; /* left record pointer */
2077
2078 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2079 rrp = xfs_btree_rec_addr(cur, 1, right);
2080
2081 xfs_btree_copy_recs(cur, lrp, rrp, 1);
2082 xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
2083
4a26e66e
CH		 2084 ASSERT(cur->bc_ops->recs_inorder(cur,
2085 xfs_btree_rec_addr(cur, lrecs - 1, left), lrp));
687b890a
CH		 2086 }
2087
2088 xfs_btree_set_numrecs(left, lrecs);
2089 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2090
2091 xfs_btree_set_numrecs(right, rrecs);
2092 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2093
2094 /*
2095 * Slide the contents of right down one entry.
2096 */
2097 XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
2098 if (level > 0) {
2099 /* It's a nonleaf. operate on keys and ptrs */
2100#ifdef DEBUG
2101 int i; /* loop index */
2102
2103 for (i = 0; i < rrecs; i++) {
2104 error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
2105 if (error)
2106 goto error0;
2107 }
2108#endif
2109 xfs_btree_shift_keys(cur,
2110 xfs_btree_key_addr(cur, 2, right),
2111 -1, rrecs);
2112 xfs_btree_shift_ptrs(cur,
2113 xfs_btree_ptr_addr(cur, 2, right),
2114 -1, rrecs);
2115
2116 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2117 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2118 } else {
2119 /* It's a leaf. operate on records */
2120 xfs_btree_shift_recs(cur,
2121 xfs_btree_rec_addr(cur, 2, right),
2122 -1, rrecs);
2123 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2124
2125 /*
2126 * If it's the first record in the block, we'll need a key
2127 * structure to pass up to the next level (updkey).
2128 */
2129 cur->bc_ops->init_key_from_rec(&key,
2130 xfs_btree_rec_addr(cur, 1, right));
2131 rkp = &key;
2132 }
2133
2134 /* Update the parent key values of right. */
2135 error = xfs_btree_updkey(cur, rkp, level + 1);
2136 if (error)
2137 goto error0;
2138
2139 /* Slide the cursor value left one. */
2140 cur->bc_ptrs[level]--;
2141
2142 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2143 *stat = 1;
2144 return 0;
2145
2146out0:
2147 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2148 *stat = 0;
2149 return 0;
2150
2151error0:
2152 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2153 return error;
2154}
2155
9eaead51
CH		 2156/*
2157 * Move 1 record right from cur/level if possible.
2158 * Update cur to reflect the new path.
2159 */
3cc7524c 2160STATIC int /* error */
9eaead51
CH		 2161xfs_btree_rshift(
2162 struct xfs_btree_cur *cur,
2163 int level,
2164 int *stat) /* success/failure */
2165{
2166 union xfs_btree_key key; /* btree key */
2167 struct xfs_buf *lbp; /* left buffer pointer */
2168 struct xfs_btree_block *left; /* left btree block */
2169 struct xfs_buf *rbp; /* right buffer pointer */
2170 struct xfs_btree_block *right; /* right btree block */
2171 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2172 union xfs_btree_ptr rptr; /* right block pointer */
2173 union xfs_btree_key *rkp; /* right btree key */
2174 int rrecs; /* right record count */
2175 int lrecs; /* left record count */
2176 int error; /* error return value */
2177 int i; /* loop counter */
2178
2179 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2180 XFS_BTREE_TRACE_ARGI(cur, level);
2181
2182 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2183 (level == cur->bc_nlevels - 1))
2184 goto out0;
2185
2186 /* Set up variables for this block as "left". */
2187 left = xfs_btree_get_block(cur, level, &lbp);
2188
2189#ifdef DEBUG
2190 error = xfs_btree_check_block(cur, left, level, lbp);
2191 if (error)
2192 goto error0;
2193#endif
2194
2195 /* If we've got no right sibling then we can't shift an entry right. */
2196 xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2197 if (xfs_btree_ptr_is_null(cur, &rptr))
2198 goto out0;
2199
2200 /*
2201 * If the cursor entry is the one that would be moved, don't
2202 * do it... it's too complicated.
2203 */
2204 lrecs = xfs_btree_get_numrecs(left);
2205 if (cur->bc_ptrs[level] >= lrecs)
2206 goto out0;
2207
2208 /* Set up the right neighbor as "right". */
2209 error = xfs_btree_read_buf_block(cur, &rptr, level, 0, &right, &rbp);
2210 if (error)
2211 goto error0;
2212
2213 /* If it's full, it can't take another entry. */
2214 rrecs = xfs_btree_get_numrecs(right);
2215 if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
2216 goto out0;
2217
2218 XFS_BTREE_STATS_INC(cur, rshift);
2219 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2220
2221 /*
2222 * Make a hole at the start of the right neighbor block, then
2223 * copy the last left block entry to the hole.
2224 */
2225 if (level > 0) {
2226 /* It's a nonleaf. make a hole in the keys and ptrs */
2227 union xfs_btree_key *lkp;
2228 union xfs_btree_ptr *lpp;
2229 union xfs_btree_ptr *rpp;
2230
2231 lkp = xfs_btree_key_addr(cur, lrecs, left);
2232 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2233 rkp = xfs_btree_key_addr(cur, 1, right);
2234 rpp = xfs_btree_ptr_addr(cur, 1, right);
2235
2236#ifdef DEBUG
2237 for (i = rrecs - 1; i >= 0; i--) {
2238 error = xfs_btree_check_ptr(cur, rpp, i, level);
2239 if (error)
2240 goto error0;
2241 }
2242#endif
2243
2244 xfs_btree_shift_keys(cur, rkp, 1, rrecs);
2245 xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
2246
2247#ifdef DEBUG
2248 error = xfs_btree_check_ptr(cur, lpp, 0, level);
2249 if (error)
2250 goto error0;
2251#endif
2252
2253 /* Now put the new data in, and log it. */
2254 xfs_btree_copy_keys(cur, rkp, lkp, 1);
2255 xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
2256
2257 xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
2258 xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
2259
4a26e66e
CH		 2260 ASSERT(cur->bc_ops->keys_inorder(cur, rkp,
2261 xfs_btree_key_addr(cur, 2, right)));
9eaead51
CH		 2262 } else {
2263 /* It's a leaf. make a hole in the records */
2264 union xfs_btree_rec *lrp;
2265 union xfs_btree_rec *rrp;
2266
2267 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2268 rrp = xfs_btree_rec_addr(cur, 1, right);
2269
2270 xfs_btree_shift_recs(cur, rrp, 1, rrecs);
2271
2272 /* Now put the new data in, and log it. */
2273 xfs_btree_copy_recs(cur, rrp, lrp, 1);
2274 xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
2275
2276 cur->bc_ops->init_key_from_rec(&key, rrp);
2277 rkp = &key;
2278
4a26e66e
CH		 2279 ASSERT(cur->bc_ops->recs_inorder(cur, rrp,
2280 xfs_btree_rec_addr(cur, 2, right)));
9eaead51
CH		 2281 }
2282
2283 /*
2284 * Decrement and log left's numrecs, bump and log right's numrecs.
2285 */
2286 xfs_btree_set_numrecs(left, --lrecs);
2287 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2288
2289 xfs_btree_set_numrecs(right, ++rrecs);
2290 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2291
2292 /*
2293 * Using a temporary cursor, update the parent key values of the
2294 * block on the right.
2295 */
2296 error = xfs_btree_dup_cursor(cur, &tcur);
2297 if (error)
2298 goto error0;
2299 i = xfs_btree_lastrec(tcur, level);
2300 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
2301
2302 error = xfs_btree_increment(tcur, level, &i);
2303 if (error)
2304 goto error1;
2305
2306 error = xfs_btree_updkey(tcur, rkp, level + 1);
2307 if (error)
2308 goto error1;
2309
2310 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2311
2312 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2313 *stat = 1;
2314 return 0;
2315
2316out0:
2317 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2318 *stat = 0;
2319 return 0;
2320
2321error0:
2322 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2323 return error;
2324
2325error1:
2326 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2327 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2328 return error;
2329}
f5eb8e7c
CH		 2330
2331/*
2332 * Split cur/level block in half.
2333 * Return new block number and the key to its first
2334 * record (to be inserted into parent).
2335 */
3cc7524c 2336STATIC int /* error */
f5eb8e7c
CH		 2337xfs_btree_split(
2338 struct xfs_btree_cur *cur,
2339 int level,
2340 union xfs_btree_ptr *ptrp,
2341 union xfs_btree_key *key,
2342 struct xfs_btree_cur **curp,
2343 int *stat) /* success/failure */
2344{
2345 union xfs_btree_ptr lptr; /* left sibling block ptr */
2346 struct xfs_buf *lbp; /* left buffer pointer */
2347 struct xfs_btree_block *left; /* left btree block */
2348 union xfs_btree_ptr rptr; /* right sibling block ptr */
2349 struct xfs_buf *rbp; /* right buffer pointer */
2350 struct xfs_btree_block *right; /* right btree block */
2351 union xfs_btree_ptr rrptr; /* right-right sibling ptr */
2352 struct xfs_buf *rrbp; /* right-right buffer pointer */
2353 struct xfs_btree_block *rrblock; /* right-right btree block */
2354 int lrecs;
2355 int rrecs;
2356 int src_index;
2357 int error; /* error return value */
2358#ifdef DEBUG
2359 int i;
2360#endif
2361
2362 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2363 XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
2364
2365 XFS_BTREE_STATS_INC(cur, split);
2366
2367 /* Set up left block (current one). */
2368 left = xfs_btree_get_block(cur, level, &lbp);
2369
2370#ifdef DEBUG
2371 error = xfs_btree_check_block(cur, left, level, lbp);
2372 if (error)
2373 goto error0;
2374#endif
2375
2376 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2377
2378 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2379 error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, 1, stat);
2380 if (error)
2381 goto error0;
2382 if (*stat == 0)
2383 goto out0;
2384 XFS_BTREE_STATS_INC(cur, alloc);
2385
2386 /* Set up the new block as "right". */
2387 error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
2388 if (error)
2389 goto error0;
2390
2391 /* Fill in the btree header for the new right block. */
ee1a47ab 2392 xfs_btree_init_block_cur(cur, rbp, xfs_btree_get_level(left), 0);
f5eb8e7c
CH		 2393
2394 /*
2395 * Split the entries between the old and the new block evenly.
2396 * Make sure that if there's an odd number of entries now, that
2397 * each new block will have the same number of entries.
2398 */
2399 lrecs = xfs_btree_get_numrecs(left);
2400 rrecs = lrecs / 2;
2401 if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
2402 rrecs++;
2403 src_index = (lrecs - rrecs + 1);
2404
2405 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2406
2407 /*
2408 * Copy btree block entries from the left block over to the
2409 * new block, the right. Update the right block and log the
2410 * changes.
2411 */
2412 if (level > 0) {
2413 /* It's a non-leaf. Move keys and pointers. */
2414 union xfs_btree_key *lkp; /* left btree key */
2415 union xfs_btree_ptr *lpp; /* left address pointer */
2416 union xfs_btree_key *rkp; /* right btree key */
2417 union xfs_btree_ptr *rpp; /* right address pointer */
2418
2419 lkp = xfs_btree_key_addr(cur, src_index, left);
2420 lpp = xfs_btree_ptr_addr(cur, src_index, left);
2421 rkp = xfs_btree_key_addr(cur, 1, right);
2422 rpp = xfs_btree_ptr_addr(cur, 1, right);
2423
2424#ifdef DEBUG
2425 for (i = src_index; i < rrecs; i++) {
2426 error = xfs_btree_check_ptr(cur, lpp, i, level);
2427 if (error)
2428 goto error0;
2429 }
2430#endif
2431
2432 xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
2433 xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
2434
2435 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2436 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2437
2438 /* Grab the keys to the entries moved to the right block */
2439 xfs_btree_copy_keys(cur, key, rkp, 1);
2440 } else {
2441 /* It's a leaf. Move records. */
2442 union xfs_btree_rec *lrp; /* left record pointer */
2443 union xfs_btree_rec *rrp; /* right record pointer */
2444
2445 lrp = xfs_btree_rec_addr(cur, src_index, left);
2446 rrp = xfs_btree_rec_addr(cur, 1, right);
2447
2448 xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
2449 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2450
2451 cur->bc_ops->init_key_from_rec(key,
2452 xfs_btree_rec_addr(cur, 1, right));
2453 }
2454
2455
2456 /*
2457 * Find the left block number by looking in the buffer.
2458 * Adjust numrecs, sibling pointers.
2459 */
2460 xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
2461 xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
2462 xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2463 xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2464
2465 lrecs -= rrecs;
2466 xfs_btree_set_numrecs(left, lrecs);
2467 xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
2468
2469 xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
2470 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
2471
2472 /*
2473 * If there's a block to the new block's right, make that block
2474 * point back to right instead of to left.
2475 */
2476 if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
2477 error = xfs_btree_read_buf_block(cur, &rrptr, level,
2478 0, &rrblock, &rrbp);
2479 if (error)
2480 goto error0;
2481 xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
2482 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
2483 }
2484 /*
2485 * If the cursor is really in the right block, move it there.
2486 * If it's just pointing past the last entry in left, then we'll
2487 * insert there, so don't change anything in that case.
2488 */
2489 if (cur->bc_ptrs[level] > lrecs + 1) {
2490 xfs_btree_setbuf(cur, level, rbp);
2491 cur->bc_ptrs[level] -= lrecs;
2492 }
2493 /*
2494 * If there are more levels, we'll need another cursor which refers
2495 * the right block, no matter where this cursor was.
2496 */
2497 if (level + 1 < cur->bc_nlevels) {
2498 error = xfs_btree_dup_cursor(cur, curp);
2499 if (error)
2500 goto error0;
2501 (*curp)->bc_ptrs[level + 1]++;
2502 }
2503 *ptrp = rptr;
2504 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2505 *stat = 1;
2506 return 0;
2507out0:
2508 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2509 *stat = 0;
2510 return 0;
2511
2512error0:
2513 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2514 return error;
2515}
344207ce 2516
ea77b0a6
CH		 2517/*
2518 * Copy the old inode root contents into a real block and make the
2519 * broot point to it.
2520 */
2521int /* error */
2522xfs_btree_new_iroot(
2523 struct xfs_btree_cur *cur, /* btree cursor */
2524 int *logflags, /* logging flags for inode */
2525 int *stat) /* return status - 0 fail */
2526{
2527 struct xfs_buf *cbp; /* buffer for cblock */
2528 struct xfs_btree_block *block; /* btree block */
2529 struct xfs_btree_block *cblock; /* child btree block */
2530 union xfs_btree_key *ckp; /* child key pointer */
2531 union xfs_btree_ptr *cpp; /* child ptr pointer */
2532 union xfs_btree_key *kp; /* pointer to btree key */
2533 union xfs_btree_ptr *pp; /* pointer to block addr */
2534 union xfs_btree_ptr nptr; /* new block addr */
2535 int level; /* btree level */
2536 int error; /* error return code */
2537#ifdef DEBUG
2538 int i; /* loop counter */
2539#endif
2540
2541 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2542 XFS_BTREE_STATS_INC(cur, newroot);
2543
2544 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
2545
2546 level = cur->bc_nlevels - 1;
2547
2548 block = xfs_btree_get_iroot(cur);
2549 pp = xfs_btree_ptr_addr(cur, 1, block);
2550
2551 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2552 error = cur->bc_ops->alloc_block(cur, pp, &nptr, 1, stat);
2553 if (error)
2554 goto error0;
2555 if (*stat == 0) {
2556 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2557 return 0;
2558 }
2559 XFS_BTREE_STATS_INC(cur, alloc);
2560
2561 /* Copy the root into a real block. */
2562 error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp);
2563 if (error)
2564 goto error0;
2565
088c9f67
DC		 2566 /*
2567 * we can't just memcpy() the root in for CRC enabled btree blocks.
2568 * In that case have to also ensure the blkno remains correct
2569 */
ea77b0a6 2570 memcpy(cblock, block, xfs_btree_block_len(cur));
088c9f67
DC		 2571 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
2572 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
2573 cblock->bb_u.l.bb_blkno = cpu_to_be64(cbp->b_bn);
2574 else
2575 cblock->bb_u.s.bb_blkno = cpu_to_be64(cbp->b_bn);
2576 }
ea77b0a6
CH		 2577
2578 be16_add_cpu(&block->bb_level, 1);
2579 xfs_btree_set_numrecs(block, 1);
2580 cur->bc_nlevels++;
2581 cur->bc_ptrs[level + 1] = 1;
2582
2583 kp = xfs_btree_key_addr(cur, 1, block);
2584 ckp = xfs_btree_key_addr(cur, 1, cblock);
2585 xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock));
2586
2587 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
2588#ifdef DEBUG
2589 for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
2590 error = xfs_btree_check_ptr(cur, pp, i, level);
2591 if (error)
2592 goto error0;
2593 }
2594#endif
2595 xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock));
2596
2597#ifdef DEBUG
2598 error = xfs_btree_check_ptr(cur, &nptr, 0, level);
2599 if (error)
2600 goto error0;
2601#endif
2602 xfs_btree_copy_ptrs(cur, pp, &nptr, 1);
2603
2604 xfs_iroot_realloc(cur->bc_private.b.ip,
2605 1 - xfs_btree_get_numrecs(cblock),
2606 cur->bc_private.b.whichfork);
2607
2608 xfs_btree_setbuf(cur, level, cbp);
2609
2610 /*
2611 * Do all this logging at the end so that
2612 * the root is at the right level.
2613 */
2614 xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS);
2615 xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2616 xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2617
2618 *logflags |=
9d87c319 2619 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork);
ea77b0a6
CH		 2620 *stat = 1;
2621 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2622 return 0;
2623error0:
2624 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2625 return error;
2626}
2627
344207ce
CH		 2628/*
2629 * Allocate a new root block, fill it in.
2630 */
3cc7524c 2631STATIC int /* error */
344207ce
CH		 2632xfs_btree_new_root(
2633 struct xfs_btree_cur *cur, /* btree cursor */
2634 int *stat) /* success/failure */
2635{
2636 struct xfs_btree_block *block; /* one half of the old root block */
2637 struct xfs_buf *bp; /* buffer containing block */
2638 int error; /* error return value */
2639 struct xfs_buf *lbp; /* left buffer pointer */
2640 struct xfs_btree_block *left; /* left btree block */
2641 struct xfs_buf *nbp; /* new (root) buffer */
2642 struct xfs_btree_block *new; /* new (root) btree block */
2643 int nptr; /* new value for key index, 1 or 2 */
2644 struct xfs_buf *rbp; /* right buffer pointer */
2645 struct xfs_btree_block *right; /* right btree block */
2646 union xfs_btree_ptr rptr;
2647 union xfs_btree_ptr lptr;
2648
2649 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2650 XFS_BTREE_STATS_INC(cur, newroot);
2651
2652 /* initialise our start point from the cursor */
2653 cur->bc_ops->init_ptr_from_cur(cur, &rptr);
2654
2655 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2656 error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, 1, stat);
2657 if (error)
2658 goto error0;
2659 if (*stat == 0)
2660 goto out0;
2661 XFS_BTREE_STATS_INC(cur, alloc);
2662
2663 /* Set up the new block. */
2664 error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp);
2665 if (error)
2666 goto error0;
2667
2668 /* Set the root in the holding structure increasing the level by 1. */
2669 cur->bc_ops->set_root(cur, &lptr, 1);
2670
2671 /*
2672 * At the previous root level there are now two blocks: the old root,
2673 * and the new block generated when it was split. We don't know which
2674 * one the cursor is pointing at, so we set up variables "left" and
2675 * "right" for each case.
2676 */
2677 block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp);
2678
2679#ifdef DEBUG
2680 error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp);
2681 if (error)
2682 goto error0;
2683#endif
2684
2685 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
2686 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
2687 /* Our block is left, pick up the right block. */
2688 lbp = bp;
2689 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2690 left = block;
2691 error = xfs_btree_read_buf_block(cur, &rptr,
2692 cur->bc_nlevels - 1, 0, &right, &rbp);
2693 if (error)
2694 goto error0;
2695 bp = rbp;
2696 nptr = 1;
2697 } else {
2698 /* Our block is right, pick up the left block. */
2699 rbp = bp;
2700 xfs_btree_buf_to_ptr(cur, rbp, &rptr);
2701 right = block;
2702 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2703 error = xfs_btree_read_buf_block(cur, &lptr,
2704 cur->bc_nlevels - 1, 0, &left, &lbp);
2705 if (error)
2706 goto error0;
2707 bp = lbp;
2708 nptr = 2;
2709 }
2710 /* Fill in the new block's btree header and log it. */
ee1a47ab 2711 xfs_btree_init_block_cur(cur, nbp, cur->bc_nlevels, 2);
344207ce
CH		 2712 xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS);
2713 ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) &&
2714 !xfs_btree_ptr_is_null(cur, &rptr));
2715
2716 /* Fill in the key data in the new root. */
2717 if (xfs_btree_get_level(left) > 0) {
2718 xfs_btree_copy_keys(cur,
2719 xfs_btree_key_addr(cur, 1, new),
2720 xfs_btree_key_addr(cur, 1, left), 1);
2721 xfs_btree_copy_keys(cur,
2722 xfs_btree_key_addr(cur, 2, new),
2723 xfs_btree_key_addr(cur, 1, right), 1);
2724 } else {
2725 cur->bc_ops->init_key_from_rec(
2726 xfs_btree_key_addr(cur, 1, new),
2727 xfs_btree_rec_addr(cur, 1, left));
2728 cur->bc_ops->init_key_from_rec(
2729 xfs_btree_key_addr(cur, 2, new),
2730 xfs_btree_rec_addr(cur, 1, right));
2731 }
2732 xfs_btree_log_keys(cur, nbp, 1, 2);
2733
2734 /* Fill in the pointer data in the new root. */
2735 xfs_btree_copy_ptrs(cur,
2736 xfs_btree_ptr_addr(cur, 1, new), &lptr, 1);
2737 xfs_btree_copy_ptrs(cur,
2738 xfs_btree_ptr_addr(cur, 2, new), &rptr, 1);
2739 xfs_btree_log_ptrs(cur, nbp, 1, 2);
2740
2741 /* Fix up the cursor. */
2742 xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
2743 cur->bc_ptrs[cur->bc_nlevels] = nptr;
2744 cur->bc_nlevels++;
2745 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2746 *stat = 1;
2747 return 0;
2748error0:
2749 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2750 return error;
2751out0:
2752 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2753 *stat = 0;
2754 return 0;
2755}
4b22a571
CH		 2756
2757STATIC int
2758xfs_btree_make_block_unfull(
2759 struct xfs_btree_cur *cur, /* btree cursor */
2760 int level, /* btree level */
2761 int numrecs,/* # of recs in block */
2762 int *oindex,/* old tree index */
2763 int *index, /* new tree index */
2764 union xfs_btree_ptr *nptr, /* new btree ptr */
2765 struct xfs_btree_cur **ncur, /* new btree cursor */
2766 union xfs_btree_rec *nrec, /* new record */
2767 int *stat)
2768{
2769 union xfs_btree_key key; /* new btree key value */
2770 int error = 0;
2771
2772 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2773 level == cur->bc_nlevels - 1) {
2774 struct xfs_inode *ip = cur->bc_private.b.ip;
2775
2776 if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) {
2777 /* A root block that can be made bigger. */
4b22a571
CH		 2778 xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork);
2779 } else {
2780 /* A root block that needs replacing */
2781 int logflags = 0;
2782
2783 error = xfs_btree_new_iroot(cur, &logflags, stat);
2784 if (error || *stat == 0)
2785 return error;
2786
2787 xfs_trans_log_inode(cur->bc_tp, ip, logflags);
2788 }
2789
2790 return 0;
2791 }
2792
2793 /* First, try shifting an entry to the right neighbor. */
2794 error = xfs_btree_rshift(cur, level, stat);
2795 if (error || *stat)
2796 return error;
2797
2798 /* Next, try shifting an entry to the left neighbor. */
2799 error = xfs_btree_lshift(cur, level, stat);
2800 if (error)
2801 return error;
2802
2803 if (*stat) {
2804 *oindex = *index = cur->bc_ptrs[level];
2805 return 0;
2806 }
2807
2808 /*
2809 * Next, try splitting the current block in half.
2810 *
2811 * If this works we have to re-set our variables because we
2812 * could be in a different block now.
2813 */
2814 error = xfs_btree_split(cur, level, nptr, &key, ncur, stat);
2815 if (error || *stat == 0)
2816 return error;
2817
2818
2819 *index = cur->bc_ptrs[level];
2820 cur->bc_ops->init_rec_from_key(&key, nrec);
2821 return 0;
2822}
2823
2824/*
2825 * Insert one record/level. Return information to the caller
2826 * allowing the next level up to proceed if necessary.
2827 */
2828STATIC int
2829xfs_btree_insrec(
2830 struct xfs_btree_cur *cur, /* btree cursor */
2831 int level, /* level to insert record at */
2832 union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
2833 union xfs_btree_rec *recp, /* i/o: record data inserted */
2834 struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
2835 int *stat) /* success/failure */
2836{
2837 struct xfs_btree_block *block; /* btree block */
2838 struct xfs_buf *bp; /* buffer for block */
2839 union xfs_btree_key key; /* btree key */
2840 union xfs_btree_ptr nptr; /* new block ptr */
2841 struct xfs_btree_cur *ncur; /* new btree cursor */
2842 union xfs_btree_rec nrec; /* new record count */
2843 int optr; /* old key/record index */
2844 int ptr; /* key/record index */
2845 int numrecs;/* number of records */
2846 int error; /* error return value */
2847#ifdef DEBUG
2848 int i;
2849#endif
2850
2851 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2852 XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp);
2853
2854 ncur = NULL;
2855
2856 /*
2857 * If we have an external root pointer, and we've made it to the
2858 * root level, allocate a new root block and we're done.
2859 */
2860 if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2861 (level >= cur->bc_nlevels)) {
2862 error = xfs_btree_new_root(cur, stat);
2863 xfs_btree_set_ptr_null(cur, ptrp);
2864
2865 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2866 return error;
2867 }
2868
2869 /* If we're off the left edge, return failure. */
2870 ptr = cur->bc_ptrs[level];
2871 if (ptr == 0) {
2872 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2873 *stat = 0;
2874 return 0;
2875 }
2876
2877 /* Make a key out of the record data to be inserted, and save it. */
2878 cur->bc_ops->init_key_from_rec(&key, recp);
2879
2880 optr = ptr;
2881
2882 XFS_BTREE_STATS_INC(cur, insrec);
2883
2884 /* Get pointers to the btree buffer and block. */
2885 block = xfs_btree_get_block(cur, level, &bp);
2886 numrecs = xfs_btree_get_numrecs(block);
2887
2888#ifdef DEBUG
2889 error = xfs_btree_check_block(cur, block, level, bp);
2890 if (error)
2891 goto error0;
2892
2893 /* Check that the new entry is being inserted in the right place. */
2894 if (ptr <= numrecs) {
2895 if (level == 0) {
4a26e66e
CH		 2896 ASSERT(cur->bc_ops->recs_inorder(cur, recp,
2897 xfs_btree_rec_addr(cur, ptr, block)));
4b22a571 2898 } else {
4a26e66e
CH		 2899 ASSERT(cur->bc_ops->keys_inorder(cur, &key,
2900 xfs_btree_key_addr(cur, ptr, block)));
4b22a571
CH		 2901 }
2902 }
2903#endif
2904
2905 /*
2906 * If the block is full, we can't insert the new entry until we
2907 * make the block un-full.
2908 */
2909 xfs_btree_set_ptr_null(cur, &nptr);
2910 if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
2911 error = xfs_btree_make_block_unfull(cur, level, numrecs,
2912 &optr, &ptr, &nptr, &ncur, &nrec, stat);
2913 if (error || *stat == 0)
2914 goto error0;
2915 }
2916
2917 /*
2918 * The current block may have changed if the block was
2919 * previously full and we have just made space in it.
2920 */
2921 block = xfs_btree_get_block(cur, level, &bp);
2922 numrecs = xfs_btree_get_numrecs(block);
2923
2924#ifdef DEBUG
2925 error = xfs_btree_check_block(cur, block, level, bp);
2926 if (error)
2927 return error;
2928#endif
2929
2930 /*
2931 * At this point we know there's room for our new entry in the block
2932 * we're pointing at.
2933 */
2934 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1);
2935
2936 if (level > 0) {
2937 /* It's a nonleaf. make a hole in the keys and ptrs */
2938 union xfs_btree_key *kp;
2939 union xfs_btree_ptr *pp;
2940
2941 kp = xfs_btree_key_addr(cur, ptr, block);
2942 pp = xfs_btree_ptr_addr(cur, ptr, block);
2943
2944#ifdef DEBUG
2945 for (i = numrecs - ptr; i >= 0; i--) {
2946 error = xfs_btree_check_ptr(cur, pp, i, level);
2947 if (error)
2948 return error;
2949 }
2950#endif
2951
2952 xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1);
2953 xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1);
2954
2955#ifdef DEBUG
2956 error = xfs_btree_check_ptr(cur, ptrp, 0, level);
2957 if (error)
2958 goto error0;
2959#endif
2960
2961 /* Now put the new data in, bump numrecs and log it. */
2962 xfs_btree_copy_keys(cur, kp, &key, 1);
2963 xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
2964 numrecs++;
2965 xfs_btree_set_numrecs(block, numrecs);
2966 xfs_btree_log_ptrs(cur, bp, ptr, numrecs);
2967 xfs_btree_log_keys(cur, bp, ptr, numrecs);
2968#ifdef DEBUG
2969 if (ptr < numrecs) {
4a26e66e
CH		 2970 ASSERT(cur->bc_ops->keys_inorder(cur, kp,
2971 xfs_btree_key_addr(cur, ptr + 1, block)));
4b22a571
CH		 2972 }
2973#endif
2974 } else {
2975 /* It's a leaf. make a hole in the records */
2976 union xfs_btree_rec *rp;
2977
2978 rp = xfs_btree_rec_addr(cur, ptr, block);
2979
2980 xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);
2981
2982 /* Now put the new data in, bump numrecs and log it. */
2983 xfs_btree_copy_recs(cur, rp, recp, 1);
2984 xfs_btree_set_numrecs(block, ++numrecs);
2985 xfs_btree_log_recs(cur, bp, ptr, numrecs);
2986#ifdef DEBUG
2987 if (ptr < numrecs) {
4a26e66e
CH		 2988 ASSERT(cur->bc_ops->recs_inorder(cur, rp,
2989 xfs_btree_rec_addr(cur, ptr + 1, block)));
4b22a571
CH		 2990 }
2991#endif
2992 }
2993
2994 /* Log the new number of records in the btree header. */
2995 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
2996
2997 /* If we inserted at the start of a block, update the parents' keys. */
2998 if (optr == 1) {
2999 error = xfs_btree_updkey(cur, &key, level + 1);
3000 if (error)
3001 goto error0;
3002 }
3003
3004 /*
3005 * If we are tracking the last record in the tree and
3006 * we are at the far right edge of the tree, update it.
3007 */
3008 if (xfs_btree_is_lastrec(cur, block, level)) {
3009 cur->bc_ops->update_lastrec(cur, block, recp,
3010 ptr, LASTREC_INSREC);
3011 }
3012
3013 /*
3014 * Return the new block number, if any.
3015 * If there is one, give back a record value and a cursor too.
3016 */
3017 *ptrp = nptr;
3018 if (!xfs_btree_ptr_is_null(cur, &nptr)) {
3019 *recp = nrec;
3020 *curp = ncur;
3021 }
3022
3023 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3024 *stat = 1;
3025 return 0;
3026
3027error0:
3028 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3029 return error;
3030}
3031
3032/*
3033 * Insert the record at the point referenced by cur.
3034 *
3035 * A multi-level split of the tree on insert will invalidate the original
3036 * cursor. All callers of this function should assume that the cursor is
3037 * no longer valid and revalidate it.
3038 */
3039int
3040xfs_btree_insert(
3041 struct xfs_btree_cur *cur,
3042 int *stat)
3043{
3044 int error; /* error return value */
3045 int i; /* result value, 0 for failure */
3046 int level; /* current level number in btree */
3047 union xfs_btree_ptr nptr; /* new block number (split result) */
3048 struct xfs_btree_cur *ncur; /* new cursor (split result) */
3049 struct xfs_btree_cur *pcur; /* previous level's cursor */
3050 union xfs_btree_rec rec; /* record to insert */
3051
3052 level = 0;
3053 ncur = NULL;
3054 pcur = cur;
3055
3056 xfs_btree_set_ptr_null(cur, &nptr);
3057 cur->bc_ops->init_rec_from_cur(cur, &rec);
3058
3059 /*
3060 * Loop going up the tree, starting at the leaf level.
3061 * Stop when we don't get a split block, that must mean that
3062 * the insert is finished with this level.
3063 */
3064 do {
3065 /*
3066 * Insert nrec/nptr into this level of the tree.
3067 * Note if we fail, nptr will be null.
3068 */
3069 error = xfs_btree_insrec(pcur, level, &nptr, &rec, &ncur, &i);
3070 if (error) {
3071 if (pcur != cur)
3072 xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
3073 goto error0;
3074 }
3075
3076 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3077 level++;
3078
3079 /*
3080 * See if the cursor we just used is trash.
3081 * Can't trash the caller's cursor, but otherwise we should
3082 * if ncur is a new cursor or we're about to be done.
3083 */
3084 if (pcur != cur &&
3085 (ncur || xfs_btree_ptr_is_null(cur, &nptr))) {
3086 /* Save the state from the cursor before we trash it */
3087 if (cur->bc_ops->update_cursor)
3088 cur->bc_ops->update_cursor(pcur, cur);
3089 cur->bc_nlevels = pcur->bc_nlevels;
3090 xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
3091 }
3092 /* If we got a new cursor, switch to it. */
3093 if (ncur) {
3094 pcur = ncur;
3095 ncur = NULL;
3096 }
3097 } while (!xfs_btree_ptr_is_null(cur, &nptr));
3098
3099 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3100 *stat = i;
3101 return 0;
3102error0:
3103 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3104 return error;
3105}
d4b3a4b7
CH		 3106
3107/*
3108 * Try to merge a non-leaf block back into the inode root.
3109 *
3110 * Note: the killroot names comes from the fact that we're effectively
3111 * killing the old root block. But because we can't just delete the
3112 * inode we have to copy the single block it was pointing to into the
3113 * inode.
3114 */
d96f8f89 3115STATIC int
d4b3a4b7
CH		 3116xfs_btree_kill_iroot(
3117 struct xfs_btree_cur *cur)
3118{
3119 int whichfork = cur->bc_private.b.whichfork;
3120 struct xfs_inode *ip = cur->bc_private.b.ip;
3121 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
3122 struct xfs_btree_block *block;
3123 struct xfs_btree_block *cblock;
3124 union xfs_btree_key *kp;
3125 union xfs_btree_key *ckp;
3126 union xfs_btree_ptr *pp;
3127 union xfs_btree_ptr *cpp;
3128 struct xfs_buf *cbp;
3129 int level;
3130 int index;
3131 int numrecs;
3132#ifdef DEBUG
3133 union xfs_btree_ptr ptr;
3134 int i;
3135#endif
3136
3137 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3138
3139 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
3140 ASSERT(cur->bc_nlevels > 1);
3141
3142 /*
3143 * Don't deal with the root block needs to be a leaf case.
3144 * We're just going to turn the thing back into extents anyway.
3145 */
3146 level = cur->bc_nlevels - 1;
3147 if (level == 1)
3148 goto out0;
3149
3150 /*
3151 * Give up if the root has multiple children.
3152 */
3153 block = xfs_btree_get_iroot(cur);
3154 if (xfs_btree_get_numrecs(block) != 1)
3155 goto out0;
3156
3157 cblock = xfs_btree_get_block(cur, level - 1, &cbp);
3158 numrecs = xfs_btree_get_numrecs(cblock);
3159
3160 /*
3161 * Only do this if the next level will fit.
3162 * Then the data must be copied up to the inode,
3163 * instead of freeing the root you free the next level.
3164 */
3165 if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level))
3166 goto out0;
3167
3168 XFS_BTREE_STATS_INC(cur, killroot);
3169
3170#ifdef DEBUG
3171 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
3172 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3173 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
3174 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3175#endif
3176
3177 index = numrecs - cur->bc_ops->get_maxrecs(cur, level);
3178 if (index) {
3179 xfs_iroot_realloc(cur->bc_private.b.ip, index,
3180 cur->bc_private.b.whichfork);
7cc95a82 3181 block = ifp->if_broot;
d4b3a4b7
CH		 3182 }
3183
3184 be16_add_cpu(&block->bb_numrecs, index);
3185 ASSERT(block->bb_numrecs == cblock->bb_numrecs);
3186
3187 kp = xfs_btree_key_addr(cur, 1, block);
3188 ckp = xfs_btree_key_addr(cur, 1, cblock);
3189 xfs_btree_copy_keys(cur, kp, ckp, numrecs);
3190
3191 pp = xfs_btree_ptr_addr(cur, 1, block);
3192 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
3193#ifdef DEBUG
3194 for (i = 0; i < numrecs; i++) {
3195 int error;
3196
3197 error = xfs_btree_check_ptr(cur, cpp, i, level - 1);
3198 if (error) {
3199 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3200 return error;
3201 }
3202 }
3203#endif
3204 xfs_btree_copy_ptrs(cur, pp, cpp, numrecs);
3205
3206 cur->bc_ops->free_block(cur, cbp);
3207 XFS_BTREE_STATS_INC(cur, free);
3208
3209 cur->bc_bufs[level - 1] = NULL;
3210 be16_add_cpu(&block->bb_level, -1);
3211 xfs_trans_log_inode(cur->bc_tp, ip,
9d87c319 3212 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork));
d4b3a4b7
CH		 3213 cur->bc_nlevels--;
3214out0:
3215 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3216 return 0;
3217}
91cca5df 3218
c0e59e1a
CH		 3219/*
3220 * Kill the current root node, and replace it with it's only child node.
3221 */
3222STATIC int
3223xfs_btree_kill_root(
3224 struct xfs_btree_cur *cur,
3225 struct xfs_buf *bp,
3226 int level,
3227 union xfs_btree_ptr *newroot)
3228{
3229 int error;
3230
3231 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3232 XFS_BTREE_STATS_INC(cur, killroot);
3233
3234 /*
3235 * Update the root pointer, decreasing the level by 1 and then
3236 * free the old root.
3237 */
3238 cur->bc_ops->set_root(cur, newroot, -1);
3239
3240 error = cur->bc_ops->free_block(cur, bp);
3241 if (error) {
3242 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3243 return error;
3244 }
3245
3246 XFS_BTREE_STATS_INC(cur, free);
3247
3248 cur->bc_bufs[level] = NULL;
3249 cur->bc_ra[level] = 0;
3250 cur->bc_nlevels--;
3251
3252 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3253 return 0;
3254}
3255
91cca5df
CH		 3256STATIC int
3257xfs_btree_dec_cursor(
3258 struct xfs_btree_cur *cur,
3259 int level,
3260 int *stat)
3261{
3262 int error;
3263 int i;
3264
3265 if (level > 0) {
3266 error = xfs_btree_decrement(cur, level, &i);
3267 if (error)
3268 return error;
3269 }
3270
3271 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3272 *stat = 1;
3273 return 0;
3274}
3275
3276/*
3277 * Single level of the btree record deletion routine.
3278 * Delete record pointed to by cur/level.
3279 * Remove the record from its block then rebalance the tree.
3280 * Return 0 for error, 1 for done, 2 to go on to the next level.
3281 */
3282STATIC int /* error */
3283xfs_btree_delrec(
3284 struct xfs_btree_cur *cur, /* btree cursor */
3285 int level, /* level removing record from */
3286 int *stat) /* fail/done/go-on */
3287{
3288 struct xfs_btree_block *block; /* btree block */
3289 union xfs_btree_ptr cptr; /* current block ptr */
3290 struct xfs_buf *bp; /* buffer for block */
3291 int error; /* error return value */
3292 int i; /* loop counter */
3293 union xfs_btree_key key; /* storage for keyp */
3294 union xfs_btree_key *keyp = &key; /* passed to the next level */
3295 union xfs_btree_ptr lptr; /* left sibling block ptr */
3296 struct xfs_buf *lbp; /* left buffer pointer */
3297 struct xfs_btree_block *left; /* left btree block */
3298 int lrecs = 0; /* left record count */
3299 int ptr; /* key/record index */
3300 union xfs_btree_ptr rptr; /* right sibling block ptr */
3301 struct xfs_buf *rbp; /* right buffer pointer */
3302 struct xfs_btree_block *right; /* right btree block */
3303 struct xfs_btree_block *rrblock; /* right-right btree block */
3304 struct xfs_buf *rrbp; /* right-right buffer pointer */
3305 int rrecs = 0; /* right record count */
3306 struct xfs_btree_cur *tcur; /* temporary btree cursor */
3307 int numrecs; /* temporary numrec count */
3308
3309 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3310 XFS_BTREE_TRACE_ARGI(cur, level);
3311
3312 tcur = NULL;
3313
3314 /* Get the index of the entry being deleted, check for nothing there. */
3315 ptr = cur->bc_ptrs[level];
3316 if (ptr == 0) {
3317 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3318 *stat = 0;
3319 return 0;
3320 }
3321
3322 /* Get the buffer & block containing the record or key/ptr. */
3323 block = xfs_btree_get_block(cur, level, &bp);
3324 numrecs = xfs_btree_get_numrecs(block);
3325
3326#ifdef DEBUG
3327 error = xfs_btree_check_block(cur, block, level, bp);
3328 if (error)
3329 goto error0;
3330#endif
3331
3332 /* Fail if we're off the end of the block. */
3333 if (ptr > numrecs) {
3334 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3335 *stat = 0;
3336 return 0;
3337 }
3338
3339 XFS_BTREE_STATS_INC(cur, delrec);
3340 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr);
3341
3342 /* Excise the entries being deleted. */
3343 if (level > 0) {
3344 /* It's a nonleaf. operate on keys and ptrs */
3345 union xfs_btree_key *lkp;
3346 union xfs_btree_ptr *lpp;
3347
3348 lkp = xfs_btree_key_addr(cur, ptr + 1, block);
3349 lpp = xfs_btree_ptr_addr(cur, ptr + 1, block);
3350
3351#ifdef DEBUG
3352 for (i = 0; i < numrecs - ptr; i++) {
3353 error = xfs_btree_check_ptr(cur, lpp, i, level);
3354 if (error)
3355 goto error0;
3356 }
3357#endif
3358
3359 if (ptr < numrecs) {
3360 xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr);
3361 xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr);
3362 xfs_btree_log_keys(cur, bp, ptr, numrecs - 1);
3363 xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1);
3364 }
3365
3366 /*
3367 * If it's the first record in the block, we'll need to pass a
3368 * key up to the next level (updkey).
3369 */
3370 if (ptr == 1)
3371 keyp = xfs_btree_key_addr(cur, 1, block);
3372 } else {
3373 /* It's a leaf. operate on records */
3374 if (ptr < numrecs) {
3375 xfs_btree_shift_recs(cur,
3376 xfs_btree_rec_addr(cur, ptr + 1, block),
3377 -1, numrecs - ptr);
3378 xfs_btree_log_recs(cur, bp, ptr, numrecs - 1);
3379 }
3380
3381 /*
3382 * If it's the first record in the block, we'll need a key
3383 * structure to pass up to the next level (updkey).
3384 */
3385 if (ptr == 1) {
3386 cur->bc_ops->init_key_from_rec(&key,
3387 xfs_btree_rec_addr(cur, 1, block));
3388 keyp = &key;
3389 }
3390 }
3391
3392 /*
3393 * Decrement and log the number of entries in the block.
3394 */
3395 xfs_btree_set_numrecs(block, --numrecs);
3396 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3397
3398 /*
3399 * If we are tracking the last record in the tree and
3400 * we are at the far right edge of the tree, update it.
3401 */
3402 if (xfs_btree_is_lastrec(cur, block, level)) {
3403 cur->bc_ops->update_lastrec(cur, block, NULL,
3404 ptr, LASTREC_DELREC);
3405 }
3406
3407 /*
3408 * We're at the root level. First, shrink the root block in-memory.
3409 * Try to get rid of the next level down. If we can't then there's
3410 * nothing left to do.
3411 */
3412 if (level == cur->bc_nlevels - 1) {
3413 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3414 xfs_iroot_realloc(cur->bc_private.b.ip, -1,
3415 cur->bc_private.b.whichfork);
3416
3417 error = xfs_btree_kill_iroot(cur);
3418 if (error)
3419 goto error0;
3420
3421 error = xfs_btree_dec_cursor(cur, level, stat);
3422 if (error)
3423 goto error0;
3424 *stat = 1;
3425 return 0;
3426 }
3427
3428 /*
3429 * If this is the root level, and there's only one entry left,
3430 * and it's NOT the leaf level, then we can get rid of this
3431 * level.
3432 */
3433 if (numrecs == 1 && level > 0) {
3434 union xfs_btree_ptr *pp;
3435 /*
3436 * pp is still set to the first pointer in the block.
3437 * Make it the new root of the btree.
3438 */
3439 pp = xfs_btree_ptr_addr(cur, 1, block);
c0e59e1a 3440 error = xfs_btree_kill_root(cur, bp, level, pp);
91cca5df
CH		 3441 if (error)
3442 goto error0;
3443 } else if (level > 0) {
3444 error = xfs_btree_dec_cursor(cur, level, stat);
3445 if (error)
3446 goto error0;
3447 }
3448 *stat = 1;
3449 return 0;
3450 }
3451
3452 /*
3453 * If we deleted the leftmost entry in the block, update the
3454 * key values above us in the tree.
3455 */
3456 if (ptr == 1) {
3457 error = xfs_btree_updkey(cur, keyp, level + 1);
3458 if (error)
3459 goto error0;
3460 }
3461
3462 /*
3463 * If the number of records remaining in the block is at least
3464 * the minimum, we're done.
3465 */
3466 if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) {
3467 error = xfs_btree_dec_cursor(cur, level, stat);
3468 if (error)
3469 goto error0;
3470 return 0;
3471 }
3472
3473 /*
3474 * Otherwise, we have to move some records around to keep the
3475 * tree balanced. Look at the left and right sibling blocks to
3476 * see if we can re-balance by moving only one record.
3477 */
3478 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3479 xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB);
3480
3481 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3482 /*
3483 * One child of root, need to get a chance to copy its contents
3484 * into the root and delete it. Can't go up to next level,
3485 * there's nothing to delete there.
3486 */
3487 if (xfs_btree_ptr_is_null(cur, &rptr) &&
3488 xfs_btree_ptr_is_null(cur, &lptr) &&
3489 level == cur->bc_nlevels - 2) {
3490 error = xfs_btree_kill_iroot(cur);
3491 if (!error)
3492 error = xfs_btree_dec_cursor(cur, level, stat);
3493 if (error)
3494 goto error0;
3495 return 0;
3496 }
3497 }
3498
3499 ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) ||
3500 !xfs_btree_ptr_is_null(cur, &lptr));
3501
3502 /*
3503 * Duplicate the cursor so our btree manipulations here won't
3504 * disrupt the next level up.
3505 */
3506 error = xfs_btree_dup_cursor(cur, &tcur);
3507 if (error)
3508 goto error0;
3509
3510 /*
3511 * If there's a right sibling, see if it's ok to shift an entry
3512 * out of it.
3513 */
3514 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3515 /*
3516 * Move the temp cursor to the last entry in the next block.
3517 * Actually any entry but the first would suffice.
3518 */
3519 i = xfs_btree_lastrec(tcur, level);
3520 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3521
3522 error = xfs_btree_increment(tcur, level, &i);
3523 if (error)
3524 goto error0;
3525 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3526
3527 i = xfs_btree_lastrec(tcur, level);
3528 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3529
3530 /* Grab a pointer to the block. */
3531 right = xfs_btree_get_block(tcur, level, &rbp);
3532#ifdef DEBUG
3533 error = xfs_btree_check_block(tcur, right, level, rbp);
3534 if (error)
3535 goto error0;
3536#endif
3537 /* Grab the current block number, for future use. */
3538 xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB);
3539
3540 /*
3541 * If right block is full enough so that removing one entry
3542 * won't make it too empty, and left-shifting an entry out
3543 * of right to us works, we're done.
3544 */
3545 if (xfs_btree_get_numrecs(right) - 1 >=
3546 cur->bc_ops->get_minrecs(tcur, level)) {
3547 error = xfs_btree_lshift(tcur, level, &i);
3548 if (error)
3549 goto error0;
3550 if (i) {
3551 ASSERT(xfs_btree_get_numrecs(block) >=
3552 cur->bc_ops->get_minrecs(tcur, level));
3553
3554 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3555 tcur = NULL;
3556
3557 error = xfs_btree_dec_cursor(cur, level, stat);
3558 if (error)
3559 goto error0;
3560 return 0;
3561 }
3562 }
3563
3564 /*
3565 * Otherwise, grab the number of records in right for
3566 * future reference, and fix up the temp cursor to point
3567 * to our block again (last record).
3568 */
3569 rrecs = xfs_btree_get_numrecs(right);
3570 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3571 i = xfs_btree_firstrec(tcur, level);
3572 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3573
3574 error = xfs_btree_decrement(tcur, level, &i);
3575 if (error)
3576 goto error0;
3577 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3578 }
3579 }
3580
3581 /*
3582 * If there's a left sibling, see if it's ok to shift an entry
3583 * out of it.
3584 */
3585 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3586 /*
3587 * Move the temp cursor to the first entry in the
3588 * previous block.
3589 */
3590 i = xfs_btree_firstrec(tcur, level);
3591 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3592
3593 error = xfs_btree_decrement(tcur, level, &i);
3594 if (error)
3595 goto error0;
3596 i = xfs_btree_firstrec(tcur, level);
3597 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3598
3599 /* Grab a pointer to the block. */
3600 left = xfs_btree_get_block(tcur, level, &lbp);
3601#ifdef DEBUG
3602 error = xfs_btree_check_block(cur, left, level, lbp);
3603 if (error)
3604 goto error0;
3605#endif
3606 /* Grab the current block number, for future use. */
3607 xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB);
3608
3609 /*
3610 * If left block is full enough so that removing one entry
3611 * won't make it too empty, and right-shifting an entry out
3612 * of left to us works, we're done.
3613 */
3614 if (xfs_btree_get_numrecs(left) - 1 >=
3615 cur->bc_ops->get_minrecs(tcur, level)) {
3616 error = xfs_btree_rshift(tcur, level, &i);
3617 if (error)
3618 goto error0;
3619 if (i) {
3620 ASSERT(xfs_btree_get_numrecs(block) >=
3621 cur->bc_ops->get_minrecs(tcur, level));
3622 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3623 tcur = NULL;
3624 if (level == 0)
3625 cur->bc_ptrs[0]++;
3626 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3627 *stat = 1;
3628 return 0;
3629 }
3630 }
3631
3632 /*
3633 * Otherwise, grab the number of records in right for
3634 * future reference.
3635 */
3636 lrecs = xfs_btree_get_numrecs(left);
3637 }
3638
3639 /* Delete the temp cursor, we're done with it. */
3640 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3641 tcur = NULL;
3642
3643 /* If here, we need to do a join to keep the tree balanced. */
3644 ASSERT(!xfs_btree_ptr_is_null(cur, &cptr));
3645
3646 if (!xfs_btree_ptr_is_null(cur, &lptr) &&
3647 lrecs + xfs_btree_get_numrecs(block) <=
3648 cur->bc_ops->get_maxrecs(cur, level)) {
3649 /*
3650 * Set "right" to be the starting block,
3651 * "left" to be the left neighbor.
3652 */
3653 rptr = cptr;
3654 right = block;
3655 rbp = bp;
3656 error = xfs_btree_read_buf_block(cur, &lptr, level,
3657 0, &left, &lbp);
3658 if (error)
3659 goto error0;
3660
3661 /*
3662 * If that won't work, see if we can join with the right neighbor block.
3663 */
3664 } else if (!xfs_btree_ptr_is_null(cur, &rptr) &&
3665 rrecs + xfs_btree_get_numrecs(block) <=
3666 cur->bc_ops->get_maxrecs(cur, level)) {
3667 /*
3668 * Set "left" to be the starting block,
3669 * "right" to be the right neighbor.
3670 */
3671 lptr = cptr;
3672 left = block;
3673 lbp = bp;
3674 error = xfs_btree_read_buf_block(cur, &rptr, level,
3675 0, &right, &rbp);
3676 if (error)
3677 goto error0;
3678
3679 /*
3680 * Otherwise, we can't fix the imbalance.
3681 * Just return. This is probably a logic error, but it's not fatal.
3682 */
3683 } else {
3684 error = xfs_btree_dec_cursor(cur, level, stat);
3685 if (error)
3686 goto error0;
3687 return 0;
3688 }
3689
3690 rrecs = xfs_btree_get_numrecs(right);
3691 lrecs = xfs_btree_get_numrecs(left);
3692
3693 /*
3694 * We're now going to join "left" and "right" by moving all the stuff
3695 * in "right" to "left" and deleting "right".
3696 */
3697 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
3698 if (level > 0) {
3699 /* It's a non-leaf. Move keys and pointers. */
3700 union xfs_btree_key *lkp; /* left btree key */
3701 union xfs_btree_ptr *lpp; /* left address pointer */
3702 union xfs_btree_key *rkp; /* right btree key */
3703 union xfs_btree_ptr *rpp; /* right address pointer */
3704
3705 lkp = xfs_btree_key_addr(cur, lrecs + 1, left);
3706 lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left);
3707 rkp = xfs_btree_key_addr(cur, 1, right);
3708 rpp = xfs_btree_ptr_addr(cur, 1, right);
3709#ifdef DEBUG
3710 for (i = 1; i < rrecs; i++) {
3711 error = xfs_btree_check_ptr(cur, rpp, i, level);
3712 if (error)
3713 goto error0;
3714 }
3715#endif
3716 xfs_btree_copy_keys(cur, lkp, rkp, rrecs);
3717 xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs);
3718
3719 xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
3720 xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
3721 } else {
3722 /* It's a leaf. Move records. */
3723 union xfs_btree_rec *lrp; /* left record pointer */
3724 union xfs_btree_rec *rrp; /* right record pointer */
3725
3726 lrp = xfs_btree_rec_addr(cur, lrecs + 1, left);
3727 rrp = xfs_btree_rec_addr(cur, 1, right);
3728
3729 xfs_btree_copy_recs(cur, lrp, rrp, rrecs);
3730 xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
3731 }
3732
3733 XFS_BTREE_STATS_INC(cur, join);
3734
3735 /*
9da096fd 3736 * Fix up the number of records and right block pointer in the
91cca5df
CH		 3737 * surviving block, and log it.
3738 */
3739 xfs_btree_set_numrecs(left, lrecs + rrecs);
3740 xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB),
3741 xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3742 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
3743
3744 /* If there is a right sibling, point it to the remaining block. */
3745 xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3746 if (!xfs_btree_ptr_is_null(cur, &cptr)) {
3747 error = xfs_btree_read_buf_block(cur, &cptr, level,
3748 0, &rrblock, &rrbp);
3749 if (error)
3750 goto error0;
3751 xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB);
3752 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
3753 }
3754
3755 /* Free the deleted block. */
3756 error = cur->bc_ops->free_block(cur, rbp);
3757 if (error)
3758 goto error0;
3759 XFS_BTREE_STATS_INC(cur, free);
3760
3761 /*
3762 * If we joined with the left neighbor, set the buffer in the
3763 * cursor to the left block, and fix up the index.
3764 */
3765 if (bp != lbp) {
3766 cur->bc_bufs[level] = lbp;
3767 cur->bc_ptrs[level] += lrecs;
3768 cur->bc_ra[level] = 0;
3769 }
3770 /*
3771 * If we joined with the right neighbor and there's a level above
3772 * us, increment the cursor at that level.
3773 */
3774 else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) ||
3775 (level + 1 < cur->bc_nlevels)) {
3776 error = xfs_btree_increment(cur, level + 1, &i);
3777 if (error)
3778 goto error0;
3779 }
3780
3781 /*
3782 * Readjust the ptr at this level if it's not a leaf, since it's
3783 * still pointing at the deletion point, which makes the cursor
3784 * inconsistent. If this makes the ptr 0, the caller fixes it up.
3785 * We can't use decrement because it would change the next level up.
3786 */
3787 if (level > 0)
3788 cur->bc_ptrs[level]--;
3789
3790 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3791 /* Return value means the next level up has something to do. */
3792 *stat = 2;
3793 return 0;
3794
3795error0:
3796 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3797 if (tcur)
3798 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
3799 return error;
3800}
3801
3802/*
3803 * Delete the record pointed to by cur.
3804 * The cursor refers to the place where the record was (could be inserted)
3805 * when the operation returns.
3806 */
3807int /* error */
3808xfs_btree_delete(
3809 struct xfs_btree_cur *cur,
3810 int *stat) /* success/failure */
3811{
3812 int error; /* error return value */
3813 int level;
3814 int i;
3815
3816 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3817
3818 /*
3819 * Go up the tree, starting at leaf level.
3820 *
3821 * If 2 is returned then a join was done; go to the next level.
3822 * Otherwise we are done.
3823 */
3824 for (level = 0, i = 2; i == 2; level++) {
3825 error = xfs_btree_delrec(cur, level, &i);
3826 if (error)
3827 goto error0;
3828 }
3829
3830 if (i == 0) {
3831 for (level = 1; level < cur->bc_nlevels; level++) {
3832 if (cur->bc_ptrs[level] == 0) {
3833 error = xfs_btree_decrement(cur, level, &i);
3834 if (error)
3835 goto error0;
3836 break;
3837 }
3838 }
3839 }
3840
3841 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3842 *stat = i;
3843 return 0;
3844error0:
3845 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3846 return error;
3847}
8cc938fe
CH		 3848
3849/*
3850 * Get the data from the pointed-to record.
3851 */
3852int /* error */
3853xfs_btree_get_rec(
3854 struct xfs_btree_cur *cur, /* btree cursor */
3855 union xfs_btree_rec **recp, /* output: btree record */
3856 int *stat) /* output: success/failure */
3857{
3858 struct xfs_btree_block *block; /* btree block */
3859 struct xfs_buf *bp; /* buffer pointer */
3860 int ptr; /* record number */
3861#ifdef DEBUG
3862 int error; /* error return value */
3863#endif
3864
3865 ptr = cur->bc_ptrs[0];
3866 block = xfs_btree_get_block(cur, 0, &bp);
3867
3868#ifdef DEBUG
3869 error = xfs_btree_check_block(cur, block, 0, bp);
3870 if (error)
3871 return error;
3872#endif
3873
3874 /*
3875 * Off the right end or left end, return failure.
3876 */
3877 if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
3878 *stat = 0;
3879 return 0;
3880 }
3881
3882 /*
3883 * Point to the record and extract its data.
3884 */
3885 *recp = xfs_btree_rec_addr(cur, ptr, block);
3886 *stat = 1;
3887 return 0;
3888}
21b5c978
DC		 3889
3890/*
3891 * Change the owner of a btree.
3892 *
3893 * The mechanism we use here is ordered buffer logging. Because we don't know
3894 * how many buffers were are going to need to modify, we don't really want to
3895 * have to make transaction reservations for the worst case of every buffer in a
3896 * full size btree as that may be more space that we can fit in the log....
3897 *
3898 * We do the btree walk in the most optimal manner possible - we have sibling
3899 * pointers so we can just walk all the blocks on each level from left to right
3900 * in a single pass, and then move to the next level and do the same. We can
3901 * also do readahead on the sibling pointers to get IO moving more quickly,
3902 * though for slow disks this is unlikely to make much difference to performance
3903 * as the amount of CPU work we have to do before moving to the next block is
3904 * relatively small.
3905 *
3906 * For each btree block that we load, modify the owner appropriately, set the
3907 * buffer as an ordered buffer and log it appropriately. We need to ensure that
3908 * we mark the region we change dirty so that if the buffer is relogged in
3909 * a subsequent transaction the changes we make here as an ordered buffer are
638f4416
DC		 3910 * correctly relogged in that transaction. If we are in recovery context, then
3911 * just queue the modified buffer as delayed write buffer so the transaction
3912 * recovery completion writes the changes to disk.
21b5c978
DC		 3913 */
3914static int
3915xfs_btree_block_change_owner(
3916 struct xfs_btree_cur *cur,
3917 int level,
638f4416
DC		 3918 __uint64_t new_owner,
3919 struct list_head *buffer_list)
21b5c978
DC		 3920{
3921 struct xfs_btree_block *block;
3922 struct xfs_buf *bp;
3923 union xfs_btree_ptr rptr;
3924
3925 /* do right sibling readahead */
3926 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
3927
3928 /* modify the owner */
3929 block = xfs_btree_get_block(cur, level, &bp);
3930 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
3931 block->bb_u.l.bb_owner = cpu_to_be64(new_owner);
3932 else
3933 block->bb_u.s.bb_owner = cpu_to_be32(new_owner);
3934
3935 /*
638f4416
DC		 3936 * If the block is a root block hosted in an inode, we might not have a
3937 * buffer pointer here and we shouldn't attempt to log the change as the
3938 * information is already held in the inode and discarded when the root
3939 * block is formatted into the on-disk inode fork. We still change it,
3940 * though, so everything is consistent in memory.
21b5c978
DC		 3941 */
3942 if (bp) {
638f4416
DC		 3943 if (cur->bc_tp) {
3944 xfs_trans_ordered_buf(cur->bc_tp, bp);
3945 xfs_btree_log_block(cur, bp, XFS_BB_OWNER);
3946 } else {
3947 xfs_buf_delwri_queue(bp, buffer_list);
3948 }
21b5c978
DC		 3949 } else {
3950 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
3951 ASSERT(level == cur->bc_nlevels - 1);
3952 }
3953
3954 /* now read rh sibling block for next iteration */
3955 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3956 if (xfs_btree_ptr_is_null(cur, &rptr))
3957 return ENOENT;
3958
3959 return xfs_btree_lookup_get_block(cur, level, &rptr, &block);
3960}
3961
3962int
3963xfs_btree_change_owner(
3964 struct xfs_btree_cur *cur,
638f4416
DC		 3965 __uint64_t new_owner,
3966 struct list_head *buffer_list)
21b5c978
DC		 3967{
3968 union xfs_btree_ptr lptr;
3969 int level;
3970 struct xfs_btree_block *block = NULL;
3971 int error = 0;
3972
3973 cur->bc_ops->init_ptr_from_cur(cur, &lptr);
3974
3975 /* for each level */
3976 for (level = cur->bc_nlevels - 1; level >= 0; level--) {
3977 /* grab the left hand block */
3978 error = xfs_btree_lookup_get_block(cur, level, &lptr, &block);
3979 if (error)
3980 return error;
3981
3982 /* readahead the left most block for the next level down */
3983 if (level > 0) {
3984 union xfs_btree_ptr *ptr;
3985
3986 ptr = xfs_btree_ptr_addr(cur, 1, block);
3987 xfs_btree_readahead_ptr(cur, ptr, 1);
3988
3989 /* save for the next iteration of the loop */
3990 lptr = *ptr;
3991 }
3992
3993 /* for each buffer in the level */
3994 do {
3995 error = xfs_btree_block_change_owner(cur, level,
638f4416
DC		 3996 new_owner,
3997 buffer_list);
21b5c978
DC		 3998 } while (!error);
3999
4000 if (error != ENOENT)
4001 return error;
4002 }
4003
4004 return 0;
4005}
Linux kernel - Deliverables
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