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xfs: move buffer invalidation to xfs_btree_free_block
[deliverable/linux.git] / fs / xfs / libxfs / 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"
a4fbe6ab 21#include "xfs_format.h"
239880ef
DC		 22#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
a844f451 24#include "xfs_bit.h"
1da177e4 25#include "xfs_mount.h"
1da177e4 26#include "xfs_inode.h"
239880ef 27#include "xfs_trans.h"
38bb7423 28#include "xfs_inode_item.h"
ee1a47ab 29#include "xfs_buf_item.h"
a844f451 30#include "xfs_btree.h"
1da177e4 31#include "xfs_error.h"
0b1b213f 32#include "xfs_trace.h"
ee1a47ab 33#include "xfs_cksum.h"
cf11da9c 34#include "xfs_alloc.h"
a45086e2 35#include "xfs_log.h"
1da177e4
LT		 36
37/*
38 * Cursor allocation zone.
39 */
40kmem_zone_t *xfs_btree_cur_zone;
41
42/*
43 * Btree magic numbers.
44 */
ee1a47ab 45static const __uint32_t xfs_magics[2][XFS_BTNUM_MAX] = {
aafc3c24
BF		 46 { XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC,
47 XFS_FIBT_MAGIC },
ee1a47ab 48 { XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC,
aafc3c24 49 XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC, XFS_FIBT_CRC_MAGIC }
1da177e4 50};
ee1a47ab
CH		 51#define xfs_btree_magic(cur) \
52 xfs_magics[!!((cur)->bc_flags & XFS_BTREE_CRC_BLOCKS)][cur->bc_btnum]
1da177e4 53
1da177e4 54
7cc95a82 55STATIC int /* error (0 or EFSCORRUPTED) */
a23f6ef8
CH		 56xfs_btree_check_lblock(
57 struct xfs_btree_cur *cur, /* btree cursor */
7cc95a82 58 struct xfs_btree_block *block, /* btree long form block pointer */
a23f6ef8
CH		 59 int level, /* level of the btree block */
60 struct xfs_buf *bp) /* buffer for block, if any */
61{
ee1a47ab 62 int lblock_ok = 1; /* block passes checks */
a23f6ef8
CH		 63 struct xfs_mount *mp; /* file system mount point */
64
65 mp = cur->bc_mp;
ee1a47ab
CH		 66
67 if (xfs_sb_version_hascrc(&mp->m_sb)) {
68 lblock_ok = lblock_ok &&
ce748eaa
ES		 69 uuid_equal(&block->bb_u.l.bb_uuid,
70 &mp->m_sb.sb_meta_uuid) &&
ee1a47ab
CH		 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 &&
d5cf09ba 81 (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK) ||
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 &&
d5cf09ba 85 (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK) ||
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);
2451337d 95 return -EFSCORRUPTED;
a23f6ef8
CH		 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 &&
ce748eaa
ES		 120 uuid_equal(&block->bb_u.s.bb_uuid,
121 &mp->m_sb.sb_meta_uuid) &&
ee1a47ab
CH		 122 block->bb_u.s.bb_blkno == cpu_to_be64(
123 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
124 }
125
126 sblock_ok = sblock_ok &&
127 be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) &&
16259e7d
CH		 128 be16_to_cpu(block->bb_level) == level &&
129 be16_to_cpu(block->bb_numrecs) <=
ce5e42db 130 cur->bc_ops->get_maxrecs(cur, level) &&
69ef921b 131 (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) ||
7cc95a82
CH		 132 be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
133 block->bb_u.s.bb_leftsib &&
69ef921b 134 (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) ||
7cc95a82
CH		 135 be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
136 block->bb_u.s.bb_rightsib;
ee1a47ab
CH		 137
138 if (unlikely(XFS_TEST_ERROR(!sblock_ok, mp,
1da177e4
LT		 139 XFS_ERRTAG_BTREE_CHECK_SBLOCK,
140 XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
141 if (bp)
0b1b213f 142 trace_xfs_btree_corrupt(bp, _RET_IP_);
ee1a47ab 143 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
2451337d 144 return -EFSCORRUPTED;
1da177e4
LT		 145 }
146 return 0;
147}
148
149/*
a23f6ef8
CH		 150 * Debug routine: check that block header is ok.
151 */
152int
153xfs_btree_check_block(
154 struct xfs_btree_cur *cur, /* btree cursor */
155 struct xfs_btree_block *block, /* generic btree block pointer */
156 int level, /* level of the btree block */
157 struct xfs_buf *bp) /* buffer containing block, if any */
158{
7cc95a82
CH		 159 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
160 return xfs_btree_check_lblock(cur, block, level, bp);
161 else
162 return xfs_btree_check_sblock(cur, block, level, bp);
a23f6ef8
CH		 163}
164
165/*
166 * Check that (long) pointer is ok.
167 */
168int /* error (0 or EFSCORRUPTED) */
169xfs_btree_check_lptr(
170 struct xfs_btree_cur *cur, /* btree cursor */
d5cf09ba 171 xfs_fsblock_t bno, /* btree block disk address */
a23f6ef8
CH		 172 int level) /* btree block level */
173{
5fb5aeee 174 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp,
a23f6ef8 175 level > 0 &&
d5cf09ba 176 bno != NULLFSBLOCK &&
a23f6ef8
CH		 177 XFS_FSB_SANITY_CHECK(cur->bc_mp, bno));
178 return 0;
179}
180
24ee0e49 181#ifdef DEBUG
a23f6ef8
CH		 182/*
183 * Check that (short) pointer is ok.
1da177e4 184 */
3cc7524c 185STATIC int /* error (0 or EFSCORRUPTED) */
1da177e4 186xfs_btree_check_sptr(
a23f6ef8
CH		 187 struct xfs_btree_cur *cur, /* btree cursor */
188 xfs_agblock_t bno, /* btree block disk address */
189 int level) /* btree block level */
1da177e4 190{
a23f6ef8 191 xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks;
1da177e4 192
5fb5aeee 193 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp,
1da177e4 194 level > 0 &&
a23f6ef8
CH		 195 bno != NULLAGBLOCK &&
196 bno != 0 &&
197 bno < agblocks);
1da177e4
LT		 198 return 0;
199}
200
a23f6ef8
CH		 201/*
202 * Check that block ptr is ok.
203 */
3cc7524c 204STATIC int /* error (0 or EFSCORRUPTED) */
a23f6ef8
CH		 205xfs_btree_check_ptr(
206 struct xfs_btree_cur *cur, /* btree cursor */
207 union xfs_btree_ptr *ptr, /* btree block disk address */
208 int index, /* offset from ptr to check */
209 int level) /* btree block level */
210{
211 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
212 return xfs_btree_check_lptr(cur,
213 be64_to_cpu((&ptr->l)[index]), level);
214 } else {
215 return xfs_btree_check_sptr(cur,
216 be32_to_cpu((&ptr->s)[index]), level);
217 }
218}
24ee0e49 219#endif
a23f6ef8 220
ee1a47ab
CH		 221/*
222 * Calculate CRC on the whole btree block and stuff it into the
223 * long-form btree header.
224 *
225 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
fef4ded8 226 * it into the buffer so recovery knows what the last modification was that made
ee1a47ab
CH		 227 * it to disk.
228 */
229void
230xfs_btree_lblock_calc_crc(
231 struct xfs_buf *bp)
232{
233 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
234 struct xfs_buf_log_item *bip = bp->b_fspriv;
235
236 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
237 return;
238 if (bip)
239 block->bb_u.l.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
f1dbcd7e 240 xfs_buf_update_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF);
ee1a47ab
CH		 241}
242
243bool
244xfs_btree_lblock_verify_crc(
245 struct xfs_buf *bp)
246{
a45086e2
BF		 247 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
248 struct xfs_mount *mp = bp->b_target->bt_mount;
249
250 if (xfs_sb_version_hascrc(&mp->m_sb)) {
251 if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.l.bb_lsn)))
252 return false;
51582170 253 return xfs_buf_verify_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF);
a45086e2 254 }
51582170 255
ee1a47ab
CH		 256 return true;
257}
258
259/*
260 * Calculate CRC on the whole btree block and stuff it into the
261 * short-form btree header.
262 *
263 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
fef4ded8 264 * it into the buffer so recovery knows what the last modification was that made
ee1a47ab
CH		 265 * it to disk.
266 */
267void
268xfs_btree_sblock_calc_crc(
269 struct xfs_buf *bp)
270{
271 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
272 struct xfs_buf_log_item *bip = bp->b_fspriv;
273
274 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
275 return;
276 if (bip)
277 block->bb_u.s.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
f1dbcd7e 278 xfs_buf_update_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF);
ee1a47ab
CH		 279}
280
281bool
282xfs_btree_sblock_verify_crc(
283 struct xfs_buf *bp)
284{
a45086e2
BF		 285 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
286 struct xfs_mount *mp = bp->b_target->bt_mount;
287
288 if (xfs_sb_version_hascrc(&mp->m_sb)) {
289 if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.s.bb_lsn)))
290 return false;
51582170 291 return xfs_buf_verify_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF);
a45086e2 292 }
51582170 293
ee1a47ab
CH		 294 return true;
295}
296
c46ee8ad
CH		 297static int
298xfs_btree_free_block(
299 struct xfs_btree_cur *cur,
300 struct xfs_buf *bp)
301{
302 int error;
303
304 error = cur->bc_ops->free_block(cur, bp);
edfd9dd5
CH		 305 if (!error) {
306 xfs_trans_binval(cur->bc_tp, bp);
c46ee8ad 307 XFS_BTREE_STATS_INC(cur, free);
edfd9dd5 308 }
c46ee8ad
CH		 309 return error;
310}
311
1da177e4
LT		 312/*
313 * Delete the btree cursor.
314 */
315void
316xfs_btree_del_cursor(
317 xfs_btree_cur_t *cur, /* btree cursor */
318 int error) /* del because of error */
319{
320 int i; /* btree level */
321
322 /*
323 * Clear the buffer pointers, and release the buffers.
324 * If we're doing this in the face of an error, we
325 * need to make sure to inspect all of the entries
326 * in the bc_bufs array for buffers to be unlocked.
327 * This is because some of the btree code works from
328 * level n down to 0, and if we get an error along
329 * the way we won't have initialized all the entries
330 * down to 0.
331 */
332 for (i = 0; i < cur->bc_nlevels; i++) {
333 if (cur->bc_bufs[i])
c0e59e1a 334 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
1da177e4
LT		 335 else if (!error)
336 break;
337 }
338 /*
339 * Can't free a bmap cursor without having dealt with the
340 * allocated indirect blocks' accounting.
341 */
342 ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP ||
343 cur->bc_private.b.allocated == 0);
344 /*
345 * Free the cursor.
346 */
347 kmem_zone_free(xfs_btree_cur_zone, cur);
348}
349
350/*
351 * Duplicate the btree cursor.
352 * Allocate a new one, copy the record, re-get the buffers.
353 */
354int /* error */
355xfs_btree_dup_cursor(
356 xfs_btree_cur_t *cur, /* input cursor */
357 xfs_btree_cur_t **ncur) /* output cursor */
358{
359 xfs_buf_t *bp; /* btree block's buffer pointer */
360 int error; /* error return value */
361 int i; /* level number of btree block */
362 xfs_mount_t *mp; /* mount structure for filesystem */
363 xfs_btree_cur_t *new; /* new cursor value */
364 xfs_trans_t *tp; /* transaction pointer, can be NULL */
365
366 tp = cur->bc_tp;
367 mp = cur->bc_mp;
561f7d17 368
1da177e4
LT		 369 /*
370 * Allocate a new cursor like the old one.
371 */
561f7d17
CH		 372 new = cur->bc_ops->dup_cursor(cur);
373
1da177e4
LT		 374 /*
375 * Copy the record currently in the cursor.
376 */
377 new->bc_rec = cur->bc_rec;
561f7d17 378
1da177e4
LT		 379 /*
380 * For each level current, re-get the buffer and copy the ptr value.
381 */
382 for (i = 0; i < new->bc_nlevels; i++) {
383 new->bc_ptrs[i] = cur->bc_ptrs[i];
384 new->bc_ra[i] = cur->bc_ra[i];
c3f8fc73
DC		 385 bp = cur->bc_bufs[i];
386 if (bp) {
387 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
388 XFS_BUF_ADDR(bp), mp->m_bsize,
3d3e6f64 389 0, &bp,
1813dd64 390 cur->bc_ops->buf_ops);
c3f8fc73 391 if (error) {
1da177e4
LT		 392 xfs_btree_del_cursor(new, error);
393 *ncur = NULL;
394 return error;
395 }
ee1a47ab
CH		 396 }
397 new->bc_bufs[i] = bp;
1da177e4 398 }
1da177e4
LT		 399 *ncur = new;
400 return 0;
401}
402
65f1eaea
CH		 403/*
404 * XFS btree block layout and addressing:
405 *
406 * There are two types of blocks in the btree: leaf and non-leaf blocks.
407 *
408 * The leaf record start with a header then followed by records containing
409 * the values. A non-leaf block also starts with the same header, and
410 * then first contains lookup keys followed by an equal number of pointers
411 * to the btree blocks at the previous level.
412 *
413 * +--------+-------+-------+-------+-------+-------+-------+
414 * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
415 * +--------+-------+-------+-------+-------+-------+-------+
416 *
417 * +--------+-------+-------+-------+-------+-------+-------+
418 * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
419 * +--------+-------+-------+-------+-------+-------+-------+
420 *
421 * The header is called struct xfs_btree_block for reasons better left unknown
422 * and comes in different versions for short (32bit) and long (64bit) block
423 * pointers. The record and key structures are defined by the btree instances
424 * and opaque to the btree core. The block pointers are simple disk endian
425 * integers, available in a short (32bit) and long (64bit) variant.
426 *
427 * The helpers below calculate the offset of a given record, key or pointer
428 * into a btree block (xfs_btree_*_offset) or return a pointer to the given
429 * record, key or pointer (xfs_btree_*_addr). Note that all addressing
430 * inside the btree block is done using indices starting at one, not zero!
431 */
432
433/*
434 * Return size of the btree block header for this btree instance.
435 */
436static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
437{
ee1a47ab
CH		 438 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
439 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
440 return XFS_BTREE_LBLOCK_CRC_LEN;
441 return XFS_BTREE_LBLOCK_LEN;
442 }
443 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
444 return XFS_BTREE_SBLOCK_CRC_LEN;
445 return XFS_BTREE_SBLOCK_LEN;
65f1eaea
CH		 446}
447
448/*
449 * Return size of btree block pointers for this btree instance.
450 */
451static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
452{
453 return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
454 sizeof(__be64) : sizeof(__be32);
455}
456
457/*
458 * Calculate offset of the n-th record in a btree block.
459 */
460STATIC size_t
461xfs_btree_rec_offset(
462 struct xfs_btree_cur *cur,
463 int n)
464{
465 return xfs_btree_block_len(cur) +
466 (n - 1) * cur->bc_ops->rec_len;
467}
468
469/*
470 * Calculate offset of the n-th key in a btree block.
471 */
472STATIC size_t
473xfs_btree_key_offset(
474 struct xfs_btree_cur *cur,
475 int n)
476{
477 return xfs_btree_block_len(cur) +
478 (n - 1) * cur->bc_ops->key_len;
479}
480
481/*
482 * Calculate offset of the n-th block pointer in a btree block.
483 */
484STATIC size_t
485xfs_btree_ptr_offset(
486 struct xfs_btree_cur *cur,
487 int n,
488 int level)
489{
490 return xfs_btree_block_len(cur) +
491 cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
492 (n - 1) * xfs_btree_ptr_len(cur);
493}
494
495/*
496 * Return a pointer to the n-th record in the btree block.
497 */
498STATIC union xfs_btree_rec *
499xfs_btree_rec_addr(
500 struct xfs_btree_cur *cur,
501 int n,
502 struct xfs_btree_block *block)
503{
504 return (union xfs_btree_rec *)
505 ((char *)block + xfs_btree_rec_offset(cur, n));
506}
507
508/*
509 * Return a pointer to the n-th key in the btree block.
510 */
511STATIC union xfs_btree_key *
512xfs_btree_key_addr(
513 struct xfs_btree_cur *cur,
514 int n,
515 struct xfs_btree_block *block)
516{
517 return (union xfs_btree_key *)
518 ((char *)block + xfs_btree_key_offset(cur, n));
519}
520
521/*
522 * Return a pointer to the n-th block pointer in the btree block.
523 */
524STATIC union xfs_btree_ptr *
525xfs_btree_ptr_addr(
526 struct xfs_btree_cur *cur,
527 int n,
528 struct xfs_btree_block *block)
529{
530 int level = xfs_btree_get_level(block);
531
532 ASSERT(block->bb_level != 0);
533
534 return (union xfs_btree_ptr *)
535 ((char *)block + xfs_btree_ptr_offset(cur, n, level));
536}
537
8186e517 538/*
1cb93863 539 * Get the root block which is stored in the inode.
8186e517
CH		 540 *
541 * For now this btree implementation assumes the btree root is always
542 * stored in the if_broot field of an inode fork.
543 */
544STATIC struct xfs_btree_block *
545xfs_btree_get_iroot(
546 struct xfs_btree_cur *cur)
547{
548 struct xfs_ifork *ifp;
549
550 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
551 return (struct xfs_btree_block *)ifp->if_broot;
552}
553
1da177e4
LT		 554/*
555 * Retrieve the block pointer from the cursor at the given level.
8186e517 556 * This may be an inode btree root or from a buffer.
1da177e4 557 */
8186e517 558STATIC struct xfs_btree_block * /* generic btree block pointer */
1da177e4 559xfs_btree_get_block(
8186e517 560 struct xfs_btree_cur *cur, /* btree cursor */
1da177e4 561 int level, /* level in btree */
8186e517 562 struct xfs_buf **bpp) /* buffer containing the block */
1da177e4 563{
8186e517
CH		 564 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
565 (level == cur->bc_nlevels - 1)) {
566 *bpp = NULL;
567 return xfs_btree_get_iroot(cur);
1da177e4 568 }
8186e517
CH		 569
570 *bpp = cur->bc_bufs[level];
571 return XFS_BUF_TO_BLOCK(*bpp);
1da177e4
LT		 572}
573
574/*
575 * Get a buffer for the block, return it with no data read.
576 * Long-form addressing.
577 */
578xfs_buf_t * /* buffer for fsbno */
579xfs_btree_get_bufl(
580 xfs_mount_t *mp, /* file system mount point */
581 xfs_trans_t *tp, /* transaction pointer */
582 xfs_fsblock_t fsbno, /* file system block number */
583 uint lock) /* lock flags for get_buf */
584{
1da177e4
LT		 585 xfs_daddr_t d; /* real disk block address */
586
587 ASSERT(fsbno != NULLFSBLOCK);
588 d = XFS_FSB_TO_DADDR(mp, fsbno);
36de9556 589 return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
1da177e4
LT		 590}
591
592/*
593 * Get a buffer for the block, return it with no data read.
594 * Short-form addressing.
595 */
596xfs_buf_t * /* buffer for agno/agbno */
597xfs_btree_get_bufs(
598 xfs_mount_t *mp, /* file system mount point */
599 xfs_trans_t *tp, /* transaction pointer */
600 xfs_agnumber_t agno, /* allocation group number */
601 xfs_agblock_t agbno, /* allocation group block number */
602 uint lock) /* lock flags for get_buf */
603{
1da177e4
LT		 604 xfs_daddr_t d; /* real disk block address */
605
606 ASSERT(agno != NULLAGNUMBER);
607 ASSERT(agbno != NULLAGBLOCK);
608 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
36de9556 609 return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
1da177e4
LT		 610}
611
1da177e4
LT		 612/*
613 * Check for the cursor referring to the last block at the given level.
614 */
615int /* 1=is last block, 0=not last block */
616xfs_btree_islastblock(
617 xfs_btree_cur_t *cur, /* btree cursor */
618 int level) /* level to check */
619{
7cc95a82 620 struct xfs_btree_block *block; /* generic btree block pointer */
1da177e4
LT		 621 xfs_buf_t *bp; /* buffer containing block */
622
623 block = xfs_btree_get_block(cur, level, &bp);
624 xfs_btree_check_block(cur, block, level, bp);
e99ab90d 625 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
d5cf09ba 626 return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
1da177e4 627 else
69ef921b 628 return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
1da177e4
LT		 629}
630
cdcf4333
CH		 631/*
632 * Change the cursor to point to the first record at the given level.
633 * Other levels are unaffected.
634 */
3cc7524c 635STATIC int /* success=1, failure=0 */
cdcf4333
CH		 636xfs_btree_firstrec(
637 xfs_btree_cur_t *cur, /* btree cursor */
638 int level) /* level to change */
639{
7cc95a82 640 struct xfs_btree_block *block; /* generic btree block pointer */
cdcf4333
CH		 641 xfs_buf_t *bp; /* buffer containing block */
642
643 /*
644 * Get the block pointer for this level.
645 */
646 block = xfs_btree_get_block(cur, level, &bp);
647 xfs_btree_check_block(cur, block, level, bp);
648 /*
649 * It's empty, there is no such record.
650 */
f2277f06 651 if (!block->bb_numrecs)
cdcf4333
CH		 652 return 0;
653 /*
654 * Set the ptr value to 1, that's the first record/key.
655 */
656 cur->bc_ptrs[level] = 1;
657 return 1;
658}
659
1da177e4
LT		 660/*
661 * Change the cursor to point to the last record in the current block
662 * at the given level. Other levels are unaffected.
663 */
3cc7524c 664STATIC int /* success=1, failure=0 */
1da177e4
LT		 665xfs_btree_lastrec(
666 xfs_btree_cur_t *cur, /* btree cursor */
667 int level) /* level to change */
668{
7cc95a82 669 struct xfs_btree_block *block; /* generic btree block pointer */
1da177e4
LT		 670 xfs_buf_t *bp; /* buffer containing block */
671
672 /*
673 * Get the block pointer for this level.
674 */
675 block = xfs_btree_get_block(cur, level, &bp);
676 xfs_btree_check_block(cur, block, level, bp);
677 /*
678 * It's empty, there is no such record.
679 */
f2277f06 680 if (!block->bb_numrecs)
1da177e4
LT		 681 return 0;
682 /*
683 * Set the ptr value to numrecs, that's the last record/key.
684 */
f2277f06 685 cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
1da177e4
LT		 686 return 1;
687}
688
689/*
690 * Compute first and last byte offsets for the fields given.
691 * Interprets the offsets table, which contains struct field offsets.
692 */
693void
694xfs_btree_offsets(
695 __int64_t fields, /* bitmask of fields */
696 const short *offsets, /* table of field offsets */
697 int nbits, /* number of bits to inspect */
698 int *first, /* output: first byte offset */
699 int *last) /* output: last byte offset */
700{
701 int i; /* current bit number */
702 __int64_t imask; /* mask for current bit number */
703
704 ASSERT(fields != 0);
705 /*
706 * Find the lowest bit, so the first byte offset.
707 */
708 for (i = 0, imask = 1LL; ; i++, imask <<= 1) {
709 if (imask & fields) {
710 *first = offsets[i];
711 break;
712 }
713 }
714 /*
715 * Find the highest bit, so the last byte offset.
716 */
717 for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) {
718 if (imask & fields) {
719 *last = offsets[i + 1] - 1;
720 break;
721 }
722 }
723}
724
725/*
726 * Get a buffer for the block, return it read in.
727 * Long-form addressing.
728 */
3d3e6f64 729int
1da177e4 730xfs_btree_read_bufl(
3d3e6f64
DC		 731 struct xfs_mount *mp, /* file system mount point */
732 struct xfs_trans *tp, /* transaction pointer */
733 xfs_fsblock_t fsbno, /* file system block number */
734 uint lock, /* lock flags for read_buf */
735 struct xfs_buf **bpp, /* buffer for fsbno */
736 int refval, /* ref count value for buffer */
1813dd64 737 const struct xfs_buf_ops *ops)
1da177e4 738{
3d3e6f64 739 struct xfs_buf *bp; /* return value */
1da177e4 740 xfs_daddr_t d; /* real disk block address */
3d3e6f64 741 int error;
1da177e4
LT		 742
743 ASSERT(fsbno != NULLFSBLOCK);
744 d = XFS_FSB_TO_DADDR(mp, fsbno);
c3f8fc73 745 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
1813dd64 746 mp->m_bsize, lock, &bp, ops);
c3f8fc73 747 if (error)
1da177e4 748 return error;
821eb21d 749 if (bp)
38f23232 750 xfs_buf_set_ref(bp, refval);
1da177e4
LT		 751 *bpp = bp;
752 return 0;
753}
754
1da177e4
LT		 755/*
756 * Read-ahead the block, don't wait for it, don't return a buffer.
757 * Long-form addressing.
758 */
759/* ARGSUSED */
760void
761xfs_btree_reada_bufl(
3d3e6f64
DC		 762 struct xfs_mount *mp, /* file system mount point */
763 xfs_fsblock_t fsbno, /* file system block number */
764 xfs_extlen_t count, /* count of filesystem blocks */
1813dd64 765 const struct xfs_buf_ops *ops)
1da177e4
LT		 766{
767 xfs_daddr_t d;
768
769 ASSERT(fsbno != NULLFSBLOCK);
770 d = XFS_FSB_TO_DADDR(mp, fsbno);
1813dd64 771 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
1da177e4
LT		 772}
773
774/*
775 * Read-ahead the block, don't wait for it, don't return a buffer.
776 * Short-form addressing.
777 */
778/* ARGSUSED */
779void
780xfs_btree_reada_bufs(
3d3e6f64
DC		 781 struct xfs_mount *mp, /* file system mount point */
782 xfs_agnumber_t agno, /* allocation group number */
783 xfs_agblock_t agbno, /* allocation group block number */
784 xfs_extlen_t count, /* count of filesystem blocks */
1813dd64 785 const struct xfs_buf_ops *ops)
1da177e4
LT		 786{
787 xfs_daddr_t d;
788
789 ASSERT(agno != NULLAGNUMBER);
790 ASSERT(agbno != NULLAGBLOCK);
791 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
1813dd64 792 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
1da177e4
LT		 793}
794
b524bfee
CH		 795STATIC int
796xfs_btree_readahead_lblock(
797 struct xfs_btree_cur *cur,
798 int lr,
799 struct xfs_btree_block *block)
800{
801 int rval = 0;
d5cf09ba
CH		 802 xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
803 xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
b524bfee 804
d5cf09ba 805 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLFSBLOCK) {
3d3e6f64 806 xfs_btree_reada_bufl(cur->bc_mp, left, 1,
1813dd64 807 cur->bc_ops->buf_ops);
b524bfee
CH		 808 rval++;
809 }
810
d5cf09ba 811 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLFSBLOCK) {
3d3e6f64 812 xfs_btree_reada_bufl(cur->bc_mp, right, 1,
1813dd64 813 cur->bc_ops->buf_ops);
b524bfee
CH		 814 rval++;
815 }
816
817 return rval;
818}
819
820STATIC int
821xfs_btree_readahead_sblock(
822 struct xfs_btree_cur *cur,
823 int lr,
824 struct xfs_btree_block *block)
825{
826 int rval = 0;
827 xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib);
828 xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib);
829
830
831 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) {
832 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
1813dd64 833 left, 1, cur->bc_ops->buf_ops);
b524bfee
CH		 834 rval++;
835 }
836
837 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) {
838 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
1813dd64 839 right, 1, cur->bc_ops->buf_ops);
b524bfee
CH		 840 rval++;
841 }
842
843 return rval;
844}
845
1da177e4
LT		 846/*
847 * Read-ahead btree blocks, at the given level.
848 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
849 */
3cc7524c 850STATIC int
b524bfee
CH		 851xfs_btree_readahead(
852 struct xfs_btree_cur *cur, /* btree cursor */
1da177e4
LT		 853 int lev, /* level in btree */
854 int lr) /* left/right bits */
855{
b524bfee
CH		 856 struct xfs_btree_block *block;
857
858 /*
859 * No readahead needed if we are at the root level and the
860 * btree root is stored in the inode.
861 */
862 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
863 (lev == cur->bc_nlevels - 1))
864 return 0;
865
866 if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
867 return 0;
1da177e4 868
1da177e4 869 cur->bc_ra[lev] |= lr;
b524bfee
CH		 870 block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
871
872 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
873 return xfs_btree_readahead_lblock(cur, lr, block);
874 return xfs_btree_readahead_sblock(cur, lr, block);
1da177e4
LT		 875}
876
21b5c978
DC		 877STATIC xfs_daddr_t
878xfs_btree_ptr_to_daddr(
879 struct xfs_btree_cur *cur,
880 union xfs_btree_ptr *ptr)
881{
882 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
d5cf09ba 883 ASSERT(ptr->l != cpu_to_be64(NULLFSBLOCK));
21b5c978
DC		 884
885 return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
886 } else {
887 ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
888 ASSERT(ptr->s != cpu_to_be32(NULLAGBLOCK));
889
890 return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
891 be32_to_cpu(ptr->s));
892 }
893}
894
895/*
896 * Readahead @count btree blocks at the given @ptr location.
897 *
898 * We don't need to care about long or short form btrees here as we have a
899 * method of converting the ptr directly to a daddr available to us.
900 */
901STATIC void
902xfs_btree_readahead_ptr(
903 struct xfs_btree_cur *cur,
904 union xfs_btree_ptr *ptr,
905 xfs_extlen_t count)
906{
907 xfs_buf_readahead(cur->bc_mp->m_ddev_targp,
908 xfs_btree_ptr_to_daddr(cur, ptr),
909 cur->bc_mp->m_bsize * count, cur->bc_ops->buf_ops);
910}
911
1da177e4
LT		 912/*
913 * Set the buffer for level "lev" in the cursor to bp, releasing
914 * any previous buffer.
915 */
c0e59e1a 916STATIC void
1da177e4
LT		 917xfs_btree_setbuf(
918 xfs_btree_cur_t *cur, /* btree cursor */
919 int lev, /* level in btree */
920 xfs_buf_t *bp) /* new buffer to set */
921{
7cc95a82 922 struct xfs_btree_block *b; /* btree block */
1da177e4 923
c0e59e1a
CH		 924 if (cur->bc_bufs[lev])
925 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]);
1da177e4
LT		 926 cur->bc_bufs[lev] = bp;
927 cur->bc_ra[lev] = 0;
c0e59e1a 928
1da177e4 929 b = XFS_BUF_TO_BLOCK(bp);
e99ab90d 930 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
d5cf09ba 931 if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK))
1da177e4 932 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
d5cf09ba 933 if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK))
1da177e4
LT		 934 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
935 } else {
69ef921b 936 if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK))
1da177e4 937 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
69ef921b 938 if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK))
1da177e4
LT		 939 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
940 }
941}
637aa50f
CH		 942
943STATIC int
944xfs_btree_ptr_is_null(
945 struct xfs_btree_cur *cur,
946 union xfs_btree_ptr *ptr)
947{
948 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
d5cf09ba 949 return ptr->l == cpu_to_be64(NULLFSBLOCK);
637aa50f 950 else
69ef921b 951 return ptr->s == cpu_to_be32(NULLAGBLOCK);
637aa50f
CH		 952}
953
4b22a571
CH		 954STATIC void
955xfs_btree_set_ptr_null(
956 struct xfs_btree_cur *cur,
957 union xfs_btree_ptr *ptr)
958{
959 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
d5cf09ba 960 ptr->l = cpu_to_be64(NULLFSBLOCK);
4b22a571
CH		 961 else
962 ptr->s = cpu_to_be32(NULLAGBLOCK);
963}
964
637aa50f
CH		 965/*
966 * Get/set/init sibling pointers
967 */
968STATIC void
969xfs_btree_get_sibling(
970 struct xfs_btree_cur *cur,
971 struct xfs_btree_block *block,
972 union xfs_btree_ptr *ptr,
973 int lr)
974{
975 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
976
977 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
978 if (lr == XFS_BB_RIGHTSIB)
979 ptr->l = block->bb_u.l.bb_rightsib;
980 else
981 ptr->l = block->bb_u.l.bb_leftsib;
982 } else {
983 if (lr == XFS_BB_RIGHTSIB)
984 ptr->s = block->bb_u.s.bb_rightsib;
985 else
986 ptr->s = block->bb_u.s.bb_leftsib;
987 }
988}
989
f5eb8e7c
CH		 990STATIC void
991xfs_btree_set_sibling(
992 struct xfs_btree_cur *cur,
993 struct xfs_btree_block *block,
994 union xfs_btree_ptr *ptr,
995 int lr)
996{
997 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
998
999 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
1000 if (lr == XFS_BB_RIGHTSIB)
1001 block->bb_u.l.bb_rightsib = ptr->l;
1002 else
1003 block->bb_u.l.bb_leftsib = ptr->l;
1004 } else {
1005 if (lr == XFS_BB_RIGHTSIB)
1006 block->bb_u.s.bb_rightsib = ptr->s;
1007 else
1008 block->bb_u.s.bb_leftsib = ptr->s;
1009 }
1010}
1011
ee1a47ab
CH		 1012void
1013xfs_btree_init_block_int(
1014 struct xfs_mount *mp,
1015 struct xfs_btree_block *buf,
1016 xfs_daddr_t blkno,
1017 __u32 magic,
1018 __u16 level,
1019 __u16 numrecs,
1020 __u64 owner,
1021 unsigned int flags)
1022{
1023 buf->bb_magic = cpu_to_be32(magic);
1024 buf->bb_level = cpu_to_be16(level);
1025 buf->bb_numrecs = cpu_to_be16(numrecs);
1026
1027 if (flags & XFS_BTREE_LONG_PTRS) {
d5cf09ba
CH		 1028 buf->bb_u.l.bb_leftsib = cpu_to_be64(NULLFSBLOCK);
1029 buf->bb_u.l.bb_rightsib = cpu_to_be64(NULLFSBLOCK);
ee1a47ab
CH		 1030 if (flags & XFS_BTREE_CRC_BLOCKS) {
1031 buf->bb_u.l.bb_blkno = cpu_to_be64(blkno);
1032 buf->bb_u.l.bb_owner = cpu_to_be64(owner);
ce748eaa 1033 uuid_copy(&buf->bb_u.l.bb_uuid, &mp->m_sb.sb_meta_uuid);
ee1a47ab 1034 buf->bb_u.l.bb_pad = 0;
b58fa554 1035 buf->bb_u.l.bb_lsn = 0;
ee1a47ab
CH		 1036 }
1037 } else {
1038 /* owner is a 32 bit value on short blocks */
1039 __u32 __owner = (__u32)owner;
1040
1041 buf->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
1042 buf->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
1043 if (flags & XFS_BTREE_CRC_BLOCKS) {
1044 buf->bb_u.s.bb_blkno = cpu_to_be64(blkno);
1045 buf->bb_u.s.bb_owner = cpu_to_be32(__owner);
ce748eaa 1046 uuid_copy(&buf->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid);
b58fa554 1047 buf->bb_u.s.bb_lsn = 0;
ee1a47ab
CH		 1048 }
1049 }
1050}
1051
b64f3a39 1052void
f5eb8e7c 1053xfs_btree_init_block(
b64f3a39
DC		 1054 struct xfs_mount *mp,
1055 struct xfs_buf *bp,
1056 __u32 magic,
1057 __u16 level,
1058 __u16 numrecs,
ee1a47ab 1059 __u64 owner,
b64f3a39 1060 unsigned int flags)
f5eb8e7c 1061{
ee1a47ab
CH		 1062 xfs_btree_init_block_int(mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1063 magic, level, numrecs, owner, flags);
f5eb8e7c
CH		 1064}
1065
b64f3a39
DC		 1066STATIC void
1067xfs_btree_init_block_cur(
1068 struct xfs_btree_cur *cur,
ee1a47ab 1069 struct xfs_buf *bp,
b64f3a39 1070 int level,
ee1a47ab 1071 int numrecs)
b64f3a39 1072{
ee1a47ab
CH		 1073 __u64 owner;
1074
1075 /*
1076 * we can pull the owner from the cursor right now as the different
1077 * owners align directly with the pointer size of the btree. This may
1078 * change in future, but is safe for current users of the generic btree
1079 * code.
1080 */
1081 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1082 owner = cur->bc_private.b.ip->i_ino;
1083 else
1084 owner = cur->bc_private.a.agno;
1085
1086 xfs_btree_init_block_int(cur->bc_mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1087 xfs_btree_magic(cur), level, numrecs,
1088 owner, cur->bc_flags);
b64f3a39
DC		 1089}
1090
278d0ca1
CH		 1091/*
1092 * Return true if ptr is the last record in the btree and
ee1a47ab 1093 * we need to track updates to this record. The decision
278d0ca1
CH		 1094 * will be further refined in the update_lastrec method.
1095 */
1096STATIC int
1097xfs_btree_is_lastrec(
1098 struct xfs_btree_cur *cur,
1099 struct xfs_btree_block *block,
1100 int level)
1101{
1102 union xfs_btree_ptr ptr;
1103
1104 if (level > 0)
1105 return 0;
1106 if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
1107 return 0;
1108
1109 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1110 if (!xfs_btree_ptr_is_null(cur, &ptr))
1111 return 0;
1112 return 1;
1113}
1114
f5eb8e7c
CH		 1115STATIC void
1116xfs_btree_buf_to_ptr(
1117 struct xfs_btree_cur *cur,
1118 struct xfs_buf *bp,
1119 union xfs_btree_ptr *ptr)
1120{
1121 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1122 ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
1123 XFS_BUF_ADDR(bp)));
1124 else {
9d87c319 1125 ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp,
f5eb8e7c
CH		 1126 XFS_BUF_ADDR(bp)));
1127 }
1128}
1129
637aa50f
CH		 1130STATIC void
1131xfs_btree_set_refs(
1132 struct xfs_btree_cur *cur,
1133 struct xfs_buf *bp)
1134{
1135 switch (cur->bc_btnum) {
1136 case XFS_BTNUM_BNO:
1137 case XFS_BTNUM_CNT:
38f23232 1138 xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF);
637aa50f
CH		 1139 break;
1140 case XFS_BTNUM_INO:
aafc3c24 1141 case XFS_BTNUM_FINO:
38f23232 1142 xfs_buf_set_ref(bp, XFS_INO_BTREE_REF);
637aa50f
CH		 1143 break;
1144 case XFS_BTNUM_BMAP:
38f23232 1145 xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF);
637aa50f
CH		 1146 break;
1147 default:
1148 ASSERT(0);
1149 }
1150}
1151
f5eb8e7c
CH		 1152STATIC int
1153xfs_btree_get_buf_block(
1154 struct xfs_btree_cur *cur,
1155 union xfs_btree_ptr *ptr,
1156 int flags,
1157 struct xfs_btree_block **block,
1158 struct xfs_buf **bpp)
1159{
1160 struct xfs_mount *mp = cur->bc_mp;
1161 xfs_daddr_t d;
1162
1163 /* need to sort out how callers deal with failures first */
0cadda1c 1164 ASSERT(!(flags & XBF_TRYLOCK));
f5eb8e7c
CH		 1165
1166 d = xfs_btree_ptr_to_daddr(cur, ptr);
1167 *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
1168 mp->m_bsize, flags);
1169
2a30f36d 1170 if (!*bpp)
2451337d 1171 return -ENOMEM;
f5eb8e7c 1172
1813dd64 1173 (*bpp)->b_ops = cur->bc_ops->buf_ops;
f5eb8e7c
CH		 1174 *block = XFS_BUF_TO_BLOCK(*bpp);
1175 return 0;
1176}
1177
637aa50f
CH		 1178/*
1179 * Read in the buffer at the given ptr and return the buffer and
1180 * the block pointer within the buffer.
1181 */
1182STATIC int
1183xfs_btree_read_buf_block(
1184 struct xfs_btree_cur *cur,
1185 union xfs_btree_ptr *ptr,
637aa50f
CH		 1186 int flags,
1187 struct xfs_btree_block **block,
1188 struct xfs_buf **bpp)
1189{
1190 struct xfs_mount *mp = cur->bc_mp;
1191 xfs_daddr_t d;
1192 int error;
1193
1194 /* need to sort out how callers deal with failures first */
0cadda1c 1195 ASSERT(!(flags & XBF_TRYLOCK));
637aa50f
CH		 1196
1197 d = xfs_btree_ptr_to_daddr(cur, ptr);
1198 error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
3d3e6f64 1199 mp->m_bsize, flags, bpp,
1813dd64 1200 cur->bc_ops->buf_ops);
637aa50f
CH		 1201 if (error)
1202 return error;
1203
637aa50f
CH		 1204 xfs_btree_set_refs(cur, *bpp);
1205 *block = XFS_BUF_TO_BLOCK(*bpp);
3d3e6f64 1206 return 0;
637aa50f
CH		 1207}
1208
38bb7423
CH		 1209/*
1210 * Copy keys from one btree block to another.
1211 */
1212STATIC void
1213xfs_btree_copy_keys(
1214 struct xfs_btree_cur *cur,
1215 union xfs_btree_key *dst_key,
1216 union xfs_btree_key *src_key,
1217 int numkeys)
1218{
1219 ASSERT(numkeys >= 0);
1220 memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
1221}
1222
278d0ca1
CH		 1223/*
1224 * Copy records from one btree block to another.
1225 */
1226STATIC void
1227xfs_btree_copy_recs(
1228 struct xfs_btree_cur *cur,
1229 union xfs_btree_rec *dst_rec,
1230 union xfs_btree_rec *src_rec,
1231 int numrecs)
1232{
1233 ASSERT(numrecs >= 0);
1234 memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
1235}
1236
9eaead51
CH		 1237/*
1238 * Copy block pointers from one btree block to another.
1239 */
1240STATIC void
1241xfs_btree_copy_ptrs(
1242 struct xfs_btree_cur *cur,
1243 union xfs_btree_ptr *dst_ptr,
1244 union xfs_btree_ptr *src_ptr,
1245 int numptrs)
1246{
1247 ASSERT(numptrs >= 0);
1248 memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
1249}
1250
1251/*
1252 * Shift keys one index left/right inside a single btree block.
1253 */
1254STATIC void
1255xfs_btree_shift_keys(
1256 struct xfs_btree_cur *cur,
1257 union xfs_btree_key *key,
1258 int dir,
1259 int numkeys)
1260{
1261 char *dst_key;
1262
1263 ASSERT(numkeys >= 0);
1264 ASSERT(dir == 1 || dir == -1);
1265
1266 dst_key = (char *)key + (dir * cur->bc_ops->key_len);
1267 memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
1268}
1269
1270/*
1271 * Shift records one index left/right inside a single btree block.
1272 */
1273STATIC void
1274xfs_btree_shift_recs(
1275 struct xfs_btree_cur *cur,
1276 union xfs_btree_rec *rec,
1277 int dir,
1278 int numrecs)
1279{
1280 char *dst_rec;
1281
1282 ASSERT(numrecs >= 0);
1283 ASSERT(dir == 1 || dir == -1);
1284
1285 dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
1286 memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
1287}
1288
1289/*
1290 * Shift block pointers one index left/right inside a single btree block.
1291 */
1292STATIC void
1293xfs_btree_shift_ptrs(
1294 struct xfs_btree_cur *cur,
1295 union xfs_btree_ptr *ptr,
1296 int dir,
1297 int numptrs)
1298{
1299 char *dst_ptr;
1300
1301 ASSERT(numptrs >= 0);
1302 ASSERT(dir == 1 || dir == -1);
1303
1304 dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
1305 memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
1306}
1307
38bb7423
CH		 1308/*
1309 * Log key values from the btree block.
1310 */
1311STATIC void
1312xfs_btree_log_keys(
1313 struct xfs_btree_cur *cur,
1314 struct xfs_buf *bp,
1315 int first,
1316 int last)
1317{
1318 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1319 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1320
1321 if (bp) {
61fe135c 1322 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
38bb7423
CH		 1323 xfs_trans_log_buf(cur->bc_tp, bp,
1324 xfs_btree_key_offset(cur, first),
1325 xfs_btree_key_offset(cur, last + 1) - 1);
1326 } else {
1327 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1328 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1329 }
1330
1331 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1332}
1333
278d0ca1
CH		 1334/*
1335 * Log record values from the btree block.
1336 */
fd6bcc5b 1337void
278d0ca1
CH		 1338xfs_btree_log_recs(
1339 struct xfs_btree_cur *cur,
1340 struct xfs_buf *bp,
1341 int first,
1342 int last)
1343{
1344 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1345 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1346
61fe135c 1347 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
278d0ca1
CH		 1348 xfs_trans_log_buf(cur->bc_tp, bp,
1349 xfs_btree_rec_offset(cur, first),
1350 xfs_btree_rec_offset(cur, last + 1) - 1);
1351
1352 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1353}
1354
9eaead51
CH		 1355/*
1356 * Log block pointer fields from a btree block (nonleaf).
1357 */
1358STATIC void
1359xfs_btree_log_ptrs(
1360 struct xfs_btree_cur *cur, /* btree cursor */
1361 struct xfs_buf *bp, /* buffer containing btree block */
1362 int first, /* index of first pointer to log */
1363 int last) /* index of last pointer to log */
1364{
1365 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1366 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1367
1368 if (bp) {
1369 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
1370 int level = xfs_btree_get_level(block);
1371
61fe135c 1372 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
9eaead51
CH		 1373 xfs_trans_log_buf(cur->bc_tp, bp,
1374 xfs_btree_ptr_offset(cur, first, level),
1375 xfs_btree_ptr_offset(cur, last + 1, level) - 1);
1376 } else {
1377 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1378 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1379 }
1380
1381 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1382}
1383
1384/*
1385 * Log fields from a btree block header.
1386 */
fd6bcc5b 1387void
9eaead51
CH		 1388xfs_btree_log_block(
1389 struct xfs_btree_cur *cur, /* btree cursor */
1390 struct xfs_buf *bp, /* buffer containing btree block */
1391 int fields) /* mask of fields: XFS_BB_... */
1392{
1393 int first; /* first byte offset logged */
1394 int last; /* last byte offset logged */
1395 static const short soffsets[] = { /* table of offsets (short) */
7cc95a82
CH		 1396 offsetof(struct xfs_btree_block, bb_magic),
1397 offsetof(struct xfs_btree_block, bb_level),
1398 offsetof(struct xfs_btree_block, bb_numrecs),
1399 offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
1400 offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
ee1a47ab
CH		 1401 offsetof(struct xfs_btree_block, bb_u.s.bb_blkno),
1402 offsetof(struct xfs_btree_block, bb_u.s.bb_lsn),
1403 offsetof(struct xfs_btree_block, bb_u.s.bb_uuid),
1404 offsetof(struct xfs_btree_block, bb_u.s.bb_owner),
1405 offsetof(struct xfs_btree_block, bb_u.s.bb_crc),
1406 XFS_BTREE_SBLOCK_CRC_LEN
9eaead51
CH		 1407 };
1408 static const short loffsets[] = { /* table of offsets (long) */
7cc95a82
CH		 1409 offsetof(struct xfs_btree_block, bb_magic),
1410 offsetof(struct xfs_btree_block, bb_level),
1411 offsetof(struct xfs_btree_block, bb_numrecs),
1412 offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
1413 offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
ee1a47ab
CH		 1414 offsetof(struct xfs_btree_block, bb_u.l.bb_blkno),
1415 offsetof(struct xfs_btree_block, bb_u.l.bb_lsn),
1416 offsetof(struct xfs_btree_block, bb_u.l.bb_uuid),
1417 offsetof(struct xfs_btree_block, bb_u.l.bb_owner),
1418 offsetof(struct xfs_btree_block, bb_u.l.bb_crc),
1419 offsetof(struct xfs_btree_block, bb_u.l.bb_pad),
1420 XFS_BTREE_LBLOCK_CRC_LEN
9eaead51
CH		 1421 };
1422
1423 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1424 XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
1425
1426 if (bp) {
ee1a47ab
CH		 1427 int nbits;
1428
1429 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
1430 /*
1431 * We don't log the CRC when updating a btree
1432 * block but instead recreate it during log
1433 * recovery. As the log buffers have checksums
1434 * of their own this is safe and avoids logging a crc
1435 * update in a lot of places.
1436 */
1437 if (fields == XFS_BB_ALL_BITS)
1438 fields = XFS_BB_ALL_BITS_CRC;
1439 nbits = XFS_BB_NUM_BITS_CRC;
1440 } else {
1441 nbits = XFS_BB_NUM_BITS;
1442 }
9eaead51
CH		 1443 xfs_btree_offsets(fields,
1444 (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
1445 loffsets : soffsets,
ee1a47ab 1446 nbits, &first, &last);
61fe135c 1447 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
9eaead51
CH		 1448 xfs_trans_log_buf(cur->bc_tp, bp, first, last);
1449 } else {
1450 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1451 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1452 }
1453
1454 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1455}
1456
637aa50f
CH		 1457/*
1458 * Increment cursor by one record at the level.
1459 * For nonzero levels the leaf-ward information is untouched.
1460 */
1461int /* error */
1462xfs_btree_increment(
1463 struct xfs_btree_cur *cur,
1464 int level,
1465 int *stat) /* success/failure */
1466{
1467 struct xfs_btree_block *block;
1468 union xfs_btree_ptr ptr;
1469 struct xfs_buf *bp;
1470 int error; /* error return value */
1471 int lev;
1472
1473 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1474 XFS_BTREE_TRACE_ARGI(cur, level);
1475
1476 ASSERT(level < cur->bc_nlevels);
1477
1478 /* Read-ahead to the right at this level. */
1479 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
1480
1481 /* Get a pointer to the btree block. */
1482 block = xfs_btree_get_block(cur, level, &bp);
1483
1484#ifdef DEBUG
1485 error = xfs_btree_check_block(cur, block, level, bp);
1486 if (error)
1487 goto error0;
1488#endif
1489
1490 /* We're done if we remain in the block after the increment. */
1491 if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
1492 goto out1;
1493
1494 /* Fail if we just went off the right edge of the tree. */
1495 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1496 if (xfs_btree_ptr_is_null(cur, &ptr))
1497 goto out0;
1498
1499 XFS_BTREE_STATS_INC(cur, increment);
1500
1501 /*
1502 * March up the tree incrementing pointers.
1503 * Stop when we don't go off the right edge of a block.
1504 */
1505 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1506 block = xfs_btree_get_block(cur, lev, &bp);
1507
1508#ifdef DEBUG
1509 error = xfs_btree_check_block(cur, block, lev, bp);
1510 if (error)
1511 goto error0;
1512#endif
1513
1514 if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
1515 break;
1516
1517 /* Read-ahead the right block for the next loop. */
1518 xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
1519 }
1520
1521 /*
1522 * If we went off the root then we are either seriously
1523 * confused or have the tree root in an inode.
1524 */
1525 if (lev == cur->bc_nlevels) {
1526 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1527 goto out0;
1528 ASSERT(0);
2451337d 1529 error = -EFSCORRUPTED;
637aa50f
CH		 1530 goto error0;
1531 }
1532 ASSERT(lev < cur->bc_nlevels);
1533
1534 /*
1535 * Now walk back down the tree, fixing up the cursor's buffer
1536 * pointers and key numbers.
1537 */
1538 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1539 union xfs_btree_ptr *ptrp;
1540
1541 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
0d7409b1
ES		 1542 --lev;
1543 error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
637aa50f
CH		 1544 if (error)
1545 goto error0;
1546
1547 xfs_btree_setbuf(cur, lev, bp);
1548 cur->bc_ptrs[lev] = 1;
1549 }
1550out1:
1551 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1552 *stat = 1;
1553 return 0;
1554
1555out0:
1556 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1557 *stat = 0;
1558 return 0;
1559
1560error0:
1561 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1562 return error;
1563}
8df4da4a
CH		 1564
1565/*
1566 * Decrement cursor by one record at the level.
1567 * For nonzero levels the leaf-ward information is untouched.
1568 */
1569int /* error */
1570xfs_btree_decrement(
1571 struct xfs_btree_cur *cur,
1572 int level,
1573 int *stat) /* success/failure */
1574{
1575 struct xfs_btree_block *block;
1576 xfs_buf_t *bp;
1577 int error; /* error return value */
1578 int lev;
1579 union xfs_btree_ptr ptr;
1580
1581 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1582 XFS_BTREE_TRACE_ARGI(cur, level);
1583
1584 ASSERT(level < cur->bc_nlevels);
1585
1586 /* Read-ahead to the left at this level. */
1587 xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
1588
1589 /* We're done if we remain in the block after the decrement. */
1590 if (--cur->bc_ptrs[level] > 0)
1591 goto out1;
1592
1593 /* Get a pointer to the btree block. */
1594 block = xfs_btree_get_block(cur, level, &bp);
1595
1596#ifdef DEBUG
1597 error = xfs_btree_check_block(cur, block, level, bp);
1598 if (error)
1599 goto error0;
1600#endif
1601
1602 /* Fail if we just went off the left edge of the tree. */
1603 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
1604 if (xfs_btree_ptr_is_null(cur, &ptr))
1605 goto out0;
1606
1607 XFS_BTREE_STATS_INC(cur, decrement);
1608
1609 /*
1610 * March up the tree decrementing pointers.
1611 * Stop when we don't go off the left edge of a block.
1612 */
1613 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1614 if (--cur->bc_ptrs[lev] > 0)
1615 break;
1616 /* Read-ahead the left block for the next loop. */
1617 xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
1618 }
1619
1620 /*
1621 * If we went off the root then we are seriously confused.
1622 * or the root of the tree is in an inode.
1623 */
1624 if (lev == cur->bc_nlevels) {
1625 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1626 goto out0;
1627 ASSERT(0);
2451337d 1628 error = -EFSCORRUPTED;
8df4da4a
CH		 1629 goto error0;
1630 }
1631 ASSERT(lev < cur->bc_nlevels);
1632
1633 /*
1634 * Now walk back down the tree, fixing up the cursor's buffer
1635 * pointers and key numbers.
1636 */
1637 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1638 union xfs_btree_ptr *ptrp;
1639
1640 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
0d7409b1
ES		 1641 --lev;
1642 error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
8df4da4a
CH		 1643 if (error)
1644 goto error0;
1645 xfs_btree_setbuf(cur, lev, bp);
1646 cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
1647 }
1648out1:
1649 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1650 *stat = 1;
1651 return 0;
1652
1653out0:
1654 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1655 *stat = 0;
1656 return 0;
1657
1658error0:
1659 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1660 return error;
1661}
1662
fe033cc8
CH		 1663STATIC int
1664xfs_btree_lookup_get_block(
1665 struct xfs_btree_cur *cur, /* btree cursor */
1666 int level, /* level in the btree */
1667 union xfs_btree_ptr *pp, /* ptr to btree block */
1668 struct xfs_btree_block **blkp) /* return btree block */
1669{
1670 struct xfs_buf *bp; /* buffer pointer for btree block */
1671 int error = 0;
1672
1673 /* special case the root block if in an inode */
1674 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1675 (level == cur->bc_nlevels - 1)) {
1676 *blkp = xfs_btree_get_iroot(cur);
1677 return 0;
1678 }
1679
1680 /*
1681 * If the old buffer at this level for the disk address we are
1682 * looking for re-use it.
1683 *
1684 * Otherwise throw it away and get a new one.
1685 */
1686 bp = cur->bc_bufs[level];
1687 if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
1688 *blkp = XFS_BUF_TO_BLOCK(bp);
1689 return 0;
1690 }
1691
0d7409b1 1692 error = xfs_btree_read_buf_block(cur, pp, 0, blkp, &bp);
fe033cc8
CH		 1693 if (error)
1694 return error;
1695
1696 xfs_btree_setbuf(cur, level, bp);
1697 return 0;
1698}
1699
1700/*
1701 * Get current search key. For level 0 we don't actually have a key
1702 * structure so we make one up from the record. For all other levels
1703 * we just return the right key.
1704 */
1705STATIC union xfs_btree_key *
1706xfs_lookup_get_search_key(
1707 struct xfs_btree_cur *cur,
1708 int level,
1709 int keyno,
1710 struct xfs_btree_block *block,
1711 union xfs_btree_key *kp)
1712{
1713 if (level == 0) {
1714 cur->bc_ops->init_key_from_rec(kp,
1715 xfs_btree_rec_addr(cur, keyno, block));
1716 return kp;
1717 }
1718
1719 return xfs_btree_key_addr(cur, keyno, block);
1720}
1721
1722/*
1723 * Lookup the record. The cursor is made to point to it, based on dir.
49d3da14 1724 * stat is set to 0 if can't find any such record, 1 for success.
fe033cc8
CH		 1725 */
1726int /* error */
1727xfs_btree_lookup(
1728 struct xfs_btree_cur *cur, /* btree cursor */
1729 xfs_lookup_t dir, /* <=, ==, or >= */
1730 int *stat) /* success/failure */
1731{
1732 struct xfs_btree_block *block; /* current btree block */
1733 __int64_t diff; /* difference for the current key */
1734 int error; /* error return value */
1735 int keyno; /* current key number */
1736 int level; /* level in the btree */
1737 union xfs_btree_ptr *pp; /* ptr to btree block */
1738 union xfs_btree_ptr ptr; /* ptr to btree block */
1739
1740 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1741 XFS_BTREE_TRACE_ARGI(cur, dir);
1742
1743 XFS_BTREE_STATS_INC(cur, lookup);
1744
1745 block = NULL;
1746 keyno = 0;
1747
1748 /* initialise start pointer from cursor */
1749 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
1750 pp = &ptr;
1751
1752 /*
1753 * Iterate over each level in the btree, starting at the root.
1754 * For each level above the leaves, find the key we need, based
1755 * on the lookup record, then follow the corresponding block
1756 * pointer down to the next level.
1757 */
1758 for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
1759 /* Get the block we need to do the lookup on. */
1760 error = xfs_btree_lookup_get_block(cur, level, pp, &block);
1761 if (error)
1762 goto error0;
1763
1764 if (diff == 0) {
1765 /*
1766 * If we already had a key match at a higher level, we
1767 * know we need to use the first entry in this block.
1768 */
1769 keyno = 1;
1770 } else {
1771 /* Otherwise search this block. Do a binary search. */
1772
1773 int high; /* high entry number */
1774 int low; /* low entry number */
1775
1776 /* Set low and high entry numbers, 1-based. */
1777 low = 1;
1778 high = xfs_btree_get_numrecs(block);
1779 if (!high) {
1780 /* Block is empty, must be an empty leaf. */
1781 ASSERT(level == 0 && cur->bc_nlevels == 1);
1782
1783 cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
1784 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1785 *stat = 0;
1786 return 0;
1787 }
1788
1789 /* Binary search the block. */
1790 while (low <= high) {
1791 union xfs_btree_key key;
1792 union xfs_btree_key *kp;
1793
1794 XFS_BTREE_STATS_INC(cur, compare);
1795
1796 /* keyno is average of low and high. */
1797 keyno = (low + high) >> 1;
1798
1799 /* Get current search key */
1800 kp = xfs_lookup_get_search_key(cur, level,
1801 keyno, block, &key);
1802
1803 /*
1804 * Compute difference to get next direction:
1805 * - less than, move right
1806 * - greater than, move left
1807 * - equal, we're done
1808 */
1809 diff = cur->bc_ops->key_diff(cur, kp);
1810 if (diff < 0)
1811 low = keyno + 1;
1812 else if (diff > 0)
1813 high = keyno - 1;
1814 else
1815 break;
1816 }
1817 }
1818
1819 /*
1820 * If there are more levels, set up for the next level
1821 * by getting the block number and filling in the cursor.
1822 */
1823 if (level > 0) {
1824 /*
1825 * If we moved left, need the previous key number,
1826 * unless there isn't one.
1827 */
1828 if (diff > 0 && --keyno < 1)
1829 keyno = 1;
1830 pp = xfs_btree_ptr_addr(cur, keyno, block);
1831
1832#ifdef DEBUG
1833 error = xfs_btree_check_ptr(cur, pp, 0, level);
1834 if (error)
1835 goto error0;
1836#endif
1837 cur->bc_ptrs[level] = keyno;
1838 }
1839 }
1840
1841 /* Done with the search. See if we need to adjust the results. */
1842 if (dir != XFS_LOOKUP_LE && diff < 0) {
1843 keyno++;
1844 /*
1845 * If ge search and we went off the end of the block, but it's
1846 * not the last block, we're in the wrong block.
1847 */
1848 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1849 if (dir == XFS_LOOKUP_GE &&
1850 keyno > xfs_btree_get_numrecs(block) &&
1851 !xfs_btree_ptr_is_null(cur, &ptr)) {
1852 int i;
1853
1854 cur->bc_ptrs[0] = keyno;
1855 error = xfs_btree_increment(cur, 0, &i);
1856 if (error)
1857 goto error0;
5fb5aeee 1858 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
fe033cc8
CH		 1859 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1860 *stat = 1;
1861 return 0;
1862 }
1863 } else if (dir == XFS_LOOKUP_LE && diff > 0)
1864 keyno--;
1865 cur->bc_ptrs[0] = keyno;
1866
1867 /* Return if we succeeded or not. */
1868 if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
1869 *stat = 0;
1870 else if (dir != XFS_LOOKUP_EQ || diff == 0)
1871 *stat = 1;
1872 else
1873 *stat = 0;
1874 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1875 return 0;
1876
1877error0:
1878 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1879 return error;
1880}
38bb7423
CH		 1881
1882/*
1883 * Update keys at all levels from here to the root along the cursor's path.
1884 */
3cc7524c 1885STATIC int
38bb7423
CH		 1886xfs_btree_updkey(
1887 struct xfs_btree_cur *cur,
1888 union xfs_btree_key *keyp,
1889 int level)
1890{
1891 struct xfs_btree_block *block;
1892 struct xfs_buf *bp;
1893 union xfs_btree_key *kp;
1894 int ptr;
1895
1896 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1897 XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
1898
1899 ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1);
1900
1901 /*
1902 * Go up the tree from this level toward the root.
1903 * At each level, update the key value to the value input.
1904 * Stop when we reach a level where the cursor isn't pointing
1905 * at the first entry in the block.
1906 */
1907 for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
1908#ifdef DEBUG
1909 int error;
1910#endif
1911 block = xfs_btree_get_block(cur, level, &bp);
1912#ifdef DEBUG
1913 error = xfs_btree_check_block(cur, block, level, bp);
1914 if (error) {
1915 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1916 return error;
1917 }
1918#endif
1919 ptr = cur->bc_ptrs[level];
1920 kp = xfs_btree_key_addr(cur, ptr, block);
1921 xfs_btree_copy_keys(cur, kp, keyp, 1);
1922 xfs_btree_log_keys(cur, bp, ptr, ptr);
1923 }
1924
1925 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1926 return 0;
1927}
278d0ca1
CH		 1928
1929/*
1930 * Update the record referred to by cur to the value in the
1931 * given record. This either works (return 0) or gets an
1932 * EFSCORRUPTED error.
1933 */
1934int
1935xfs_btree_update(
1936 struct xfs_btree_cur *cur,
1937 union xfs_btree_rec *rec)
1938{
1939 struct xfs_btree_block *block;
1940 struct xfs_buf *bp;
1941 int error;
1942 int ptr;
1943 union xfs_btree_rec *rp;
1944
1945 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1946 XFS_BTREE_TRACE_ARGR(cur, rec);
1947
1948 /* Pick up the current block. */
1949 block = xfs_btree_get_block(cur, 0, &bp);
1950
1951#ifdef DEBUG
1952 error = xfs_btree_check_block(cur, block, 0, bp);
1953 if (error)
1954 goto error0;
1955#endif
1956 /* Get the address of the rec to be updated. */
1957 ptr = cur->bc_ptrs[0];
1958 rp = xfs_btree_rec_addr(cur, ptr, block);
1959
1960 /* Fill in the new contents and log them. */
1961 xfs_btree_copy_recs(cur, rp, rec, 1);
1962 xfs_btree_log_recs(cur, bp, ptr, ptr);
1963
1964 /*
1965 * If we are tracking the last record in the tree and
1966 * we are at the far right edge of the tree, update it.
1967 */
1968 if (xfs_btree_is_lastrec(cur, block, 0)) {
1969 cur->bc_ops->update_lastrec(cur, block, rec,
1970 ptr, LASTREC_UPDATE);
1971 }
1972
1973 /* Updating first rec in leaf. Pass new key value up to our parent. */
1974 if (ptr == 1) {
1975 union xfs_btree_key key;
1976
1977 cur->bc_ops->init_key_from_rec(&key, rec);
1978 error = xfs_btree_updkey(cur, &key, 1);
1979 if (error)
1980 goto error0;
1981 }
1982
1983 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1984 return 0;
1985
1986error0:
1987 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1988 return error;
1989}
1990
687b890a
CH		 1991/*
1992 * Move 1 record left from cur/level if possible.
1993 * Update cur to reflect the new path.
1994 */
3cc7524c 1995STATIC int /* error */
687b890a
CH		 1996xfs_btree_lshift(
1997 struct xfs_btree_cur *cur,
1998 int level,
1999 int *stat) /* success/failure */
2000{
2001 union xfs_btree_key key; /* btree key */
2002 struct xfs_buf *lbp; /* left buffer pointer */
2003 struct xfs_btree_block *left; /* left btree block */
2004 int lrecs; /* left record count */
2005 struct xfs_buf *rbp; /* right buffer pointer */
2006 struct xfs_btree_block *right; /* right btree block */
2007 int rrecs; /* right record count */
2008 union xfs_btree_ptr lptr; /* left btree pointer */
2009 union xfs_btree_key *rkp = NULL; /* right btree key */
2010 union xfs_btree_ptr *rpp = NULL; /* right address pointer */
2011 union xfs_btree_rec *rrp = NULL; /* right record pointer */
2012 int error; /* error return value */
2013
2014 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2015 XFS_BTREE_TRACE_ARGI(cur, level);
2016
2017 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2018 level == cur->bc_nlevels - 1)
2019 goto out0;
2020
2021 /* Set up variables for this block as "right". */
2022 right = xfs_btree_get_block(cur, level, &rbp);
2023
2024#ifdef DEBUG
2025 error = xfs_btree_check_block(cur, right, level, rbp);
2026 if (error)
2027 goto error0;
2028#endif
2029
2030 /* If we've got no left sibling then we can't shift an entry left. */
2031 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2032 if (xfs_btree_ptr_is_null(cur, &lptr))
2033 goto out0;
2034
2035 /*
2036 * If the cursor entry is the one that would be moved, don't
2037 * do it... it's too complicated.
2038 */
2039 if (cur->bc_ptrs[level] <= 1)
2040 goto out0;
2041
2042 /* Set up the left neighbor as "left". */
0d7409b1 2043 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
687b890a
CH		 2044 if (error)
2045 goto error0;
2046
2047 /* If it's full, it can't take another entry. */
2048 lrecs = xfs_btree_get_numrecs(left);
2049 if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
2050 goto out0;
2051
2052 rrecs = xfs_btree_get_numrecs(right);
2053
2054 /*
2055 * We add one entry to the left side and remove one for the right side.
9da096fd 2056 * Account for it here, the changes will be updated on disk and logged
687b890a
CH		 2057 * later.
2058 */
2059 lrecs++;
2060 rrecs--;
2061
2062 XFS_BTREE_STATS_INC(cur, lshift);
2063 XFS_BTREE_STATS_ADD(cur, moves, 1);
2064
2065 /*
2066 * If non-leaf, copy a key and a ptr to the left block.
2067 * Log the changes to the left block.
2068 */
2069 if (level > 0) {
2070 /* It's a non-leaf. Move keys and pointers. */
2071 union xfs_btree_key *lkp; /* left btree key */
2072 union xfs_btree_ptr *lpp; /* left address pointer */
2073
2074 lkp = xfs_btree_key_addr(cur, lrecs, left);
2075 rkp = xfs_btree_key_addr(cur, 1, right);
2076
2077 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2078 rpp = xfs_btree_ptr_addr(cur, 1, right);
2079#ifdef DEBUG
2080 error = xfs_btree_check_ptr(cur, rpp, 0, level);
2081 if (error)
2082 goto error0;
2083#endif
2084 xfs_btree_copy_keys(cur, lkp, rkp, 1);
2085 xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
2086
2087 xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
2088 xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
2089
4a26e66e
CH		 2090 ASSERT(cur->bc_ops->keys_inorder(cur,
2091 xfs_btree_key_addr(cur, lrecs - 1, left), lkp));
687b890a
CH		 2092 } else {
2093 /* It's a leaf. Move records. */
2094 union xfs_btree_rec *lrp; /* left record pointer */
2095
2096 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2097 rrp = xfs_btree_rec_addr(cur, 1, right);
2098
2099 xfs_btree_copy_recs(cur, lrp, rrp, 1);
2100 xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
2101
4a26e66e
CH		 2102 ASSERT(cur->bc_ops->recs_inorder(cur,
2103 xfs_btree_rec_addr(cur, lrecs - 1, left), lrp));
687b890a
CH		 2104 }
2105
2106 xfs_btree_set_numrecs(left, lrecs);
2107 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2108
2109 xfs_btree_set_numrecs(right, rrecs);
2110 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2111
2112 /*
2113 * Slide the contents of right down one entry.
2114 */
2115 XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
2116 if (level > 0) {
2117 /* It's a nonleaf. operate on keys and ptrs */
2118#ifdef DEBUG
2119 int i; /* loop index */
2120
2121 for (i = 0; i < rrecs; i++) {
2122 error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
2123 if (error)
2124 goto error0;
2125 }
2126#endif
2127 xfs_btree_shift_keys(cur,
2128 xfs_btree_key_addr(cur, 2, right),
2129 -1, rrecs);
2130 xfs_btree_shift_ptrs(cur,
2131 xfs_btree_ptr_addr(cur, 2, right),
2132 -1, rrecs);
2133
2134 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2135 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2136 } else {
2137 /* It's a leaf. operate on records */
2138 xfs_btree_shift_recs(cur,
2139 xfs_btree_rec_addr(cur, 2, right),
2140 -1, rrecs);
2141 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2142
2143 /*
2144 * If it's the first record in the block, we'll need a key
2145 * structure to pass up to the next level (updkey).
2146 */
2147 cur->bc_ops->init_key_from_rec(&key,
2148 xfs_btree_rec_addr(cur, 1, right));
2149 rkp = &key;
2150 }
2151
2152 /* Update the parent key values of right. */
2153 error = xfs_btree_updkey(cur, rkp, level + 1);
2154 if (error)
2155 goto error0;
2156
2157 /* Slide the cursor value left one. */
2158 cur->bc_ptrs[level]--;
2159
2160 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2161 *stat = 1;
2162 return 0;
2163
2164out0:
2165 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2166 *stat = 0;
2167 return 0;
2168
2169error0:
2170 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2171 return error;
2172}
2173
9eaead51
CH		 2174/*
2175 * Move 1 record right from cur/level if possible.
2176 * Update cur to reflect the new path.
2177 */
3cc7524c 2178STATIC int /* error */
9eaead51
CH		 2179xfs_btree_rshift(
2180 struct xfs_btree_cur *cur,
2181 int level,
2182 int *stat) /* success/failure */
2183{
2184 union xfs_btree_key key; /* btree key */
2185 struct xfs_buf *lbp; /* left buffer pointer */
2186 struct xfs_btree_block *left; /* left btree block */
2187 struct xfs_buf *rbp; /* right buffer pointer */
2188 struct xfs_btree_block *right; /* right btree block */
2189 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2190 union xfs_btree_ptr rptr; /* right block pointer */
2191 union xfs_btree_key *rkp; /* right btree key */
2192 int rrecs; /* right record count */
2193 int lrecs; /* left record count */
2194 int error; /* error return value */
2195 int i; /* loop counter */
2196
2197 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2198 XFS_BTREE_TRACE_ARGI(cur, level);
2199
2200 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2201 (level == cur->bc_nlevels - 1))
2202 goto out0;
2203
2204 /* Set up variables for this block as "left". */
2205 left = xfs_btree_get_block(cur, level, &lbp);
2206
2207#ifdef DEBUG
2208 error = xfs_btree_check_block(cur, left, level, lbp);
2209 if (error)
2210 goto error0;
2211#endif
2212
2213 /* If we've got no right sibling then we can't shift an entry right. */
2214 xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2215 if (xfs_btree_ptr_is_null(cur, &rptr))
2216 goto out0;
2217
2218 /*
2219 * If the cursor entry is the one that would be moved, don't
2220 * do it... it's too complicated.
2221 */
2222 lrecs = xfs_btree_get_numrecs(left);
2223 if (cur->bc_ptrs[level] >= lrecs)
2224 goto out0;
2225
2226 /* Set up the right neighbor as "right". */
0d7409b1 2227 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
9eaead51
CH		 2228 if (error)
2229 goto error0;
2230
2231 /* If it's full, it can't take another entry. */
2232 rrecs = xfs_btree_get_numrecs(right);
2233 if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
2234 goto out0;
2235
2236 XFS_BTREE_STATS_INC(cur, rshift);
2237 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2238
2239 /*
2240 * Make a hole at the start of the right neighbor block, then
2241 * copy the last left block entry to the hole.
2242 */
2243 if (level > 0) {
2244 /* It's a nonleaf. make a hole in the keys and ptrs */
2245 union xfs_btree_key *lkp;
2246 union xfs_btree_ptr *lpp;
2247 union xfs_btree_ptr *rpp;
2248
2249 lkp = xfs_btree_key_addr(cur, lrecs, left);
2250 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2251 rkp = xfs_btree_key_addr(cur, 1, right);
2252 rpp = xfs_btree_ptr_addr(cur, 1, right);
2253
2254#ifdef DEBUG
2255 for (i = rrecs - 1; i >= 0; i--) {
2256 error = xfs_btree_check_ptr(cur, rpp, i, level);
2257 if (error)
2258 goto error0;
2259 }
2260#endif
2261
2262 xfs_btree_shift_keys(cur, rkp, 1, rrecs);
2263 xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
2264
2265#ifdef DEBUG
2266 error = xfs_btree_check_ptr(cur, lpp, 0, level);
2267 if (error)
2268 goto error0;
2269#endif
2270
2271 /* Now put the new data in, and log it. */
2272 xfs_btree_copy_keys(cur, rkp, lkp, 1);
2273 xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
2274
2275 xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
2276 xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
2277
4a26e66e
CH		 2278 ASSERT(cur->bc_ops->keys_inorder(cur, rkp,
2279 xfs_btree_key_addr(cur, 2, right)));
9eaead51
CH		 2280 } else {
2281 /* It's a leaf. make a hole in the records */
2282 union xfs_btree_rec *lrp;
2283 union xfs_btree_rec *rrp;
2284
2285 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2286 rrp = xfs_btree_rec_addr(cur, 1, right);
2287
2288 xfs_btree_shift_recs(cur, rrp, 1, rrecs);
2289
2290 /* Now put the new data in, and log it. */
2291 xfs_btree_copy_recs(cur, rrp, lrp, 1);
2292 xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
2293
2294 cur->bc_ops->init_key_from_rec(&key, rrp);
2295 rkp = &key;
2296
4a26e66e
CH		 2297 ASSERT(cur->bc_ops->recs_inorder(cur, rrp,
2298 xfs_btree_rec_addr(cur, 2, right)));
9eaead51
CH		 2299 }
2300
2301 /*
2302 * Decrement and log left's numrecs, bump and log right's numrecs.
2303 */
2304 xfs_btree_set_numrecs(left, --lrecs);
2305 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2306
2307 xfs_btree_set_numrecs(right, ++rrecs);
2308 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2309
2310 /*
2311 * Using a temporary cursor, update the parent key values of the
2312 * block on the right.
2313 */
2314 error = xfs_btree_dup_cursor(cur, &tcur);
2315 if (error)
2316 goto error0;
2317 i = xfs_btree_lastrec(tcur, level);
c29aad41 2318 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
9eaead51
CH		 2319
2320 error = xfs_btree_increment(tcur, level, &i);
2321 if (error)
2322 goto error1;
2323
2324 error = xfs_btree_updkey(tcur, rkp, level + 1);
2325 if (error)
2326 goto error1;
2327
2328 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2329
2330 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2331 *stat = 1;
2332 return 0;
2333
2334out0:
2335 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2336 *stat = 0;
2337 return 0;
2338
2339error0:
2340 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2341 return error;
2342
2343error1:
2344 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2345 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2346 return error;
2347}
f5eb8e7c
CH		 2348
2349/*
2350 * Split cur/level block in half.
2351 * Return new block number and the key to its first
2352 * record (to be inserted into parent).
2353 */
3cc7524c 2354STATIC int /* error */
cf11da9c 2355__xfs_btree_split(
f5eb8e7c
CH		 2356 struct xfs_btree_cur *cur,
2357 int level,
2358 union xfs_btree_ptr *ptrp,
2359 union xfs_btree_key *key,
2360 struct xfs_btree_cur **curp,
2361 int *stat) /* success/failure */
2362{
2363 union xfs_btree_ptr lptr; /* left sibling block ptr */
2364 struct xfs_buf *lbp; /* left buffer pointer */
2365 struct xfs_btree_block *left; /* left btree block */
2366 union xfs_btree_ptr rptr; /* right sibling block ptr */
2367 struct xfs_buf *rbp; /* right buffer pointer */
2368 struct xfs_btree_block *right; /* right btree block */
2369 union xfs_btree_ptr rrptr; /* right-right sibling ptr */
2370 struct xfs_buf *rrbp; /* right-right buffer pointer */
2371 struct xfs_btree_block *rrblock; /* right-right btree block */
2372 int lrecs;
2373 int rrecs;
2374 int src_index;
2375 int error; /* error return value */
2376#ifdef DEBUG
2377 int i;
2378#endif
2379
2380 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2381 XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
2382
2383 XFS_BTREE_STATS_INC(cur, split);
2384
2385 /* Set up left block (current one). */
2386 left = xfs_btree_get_block(cur, level, &lbp);
2387
2388#ifdef DEBUG
2389 error = xfs_btree_check_block(cur, left, level, lbp);
2390 if (error)
2391 goto error0;
2392#endif
2393
2394 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2395
2396 /* Allocate the new block. If we can't do it, we're toast. Give up. */
6f8950cd 2397 error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, stat);
f5eb8e7c
CH		 2398 if (error)
2399 goto error0;
2400 if (*stat == 0)
2401 goto out0;
2402 XFS_BTREE_STATS_INC(cur, alloc);
2403
2404 /* Set up the new block as "right". */
2405 error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
2406 if (error)
2407 goto error0;
2408
2409 /* Fill in the btree header for the new right block. */
ee1a47ab 2410 xfs_btree_init_block_cur(cur, rbp, xfs_btree_get_level(left), 0);
f5eb8e7c
CH		 2411
2412 /*
2413 * Split the entries between the old and the new block evenly.
2414 * Make sure that if there's an odd number of entries now, that
2415 * each new block will have the same number of entries.
2416 */
2417 lrecs = xfs_btree_get_numrecs(left);
2418 rrecs = lrecs / 2;
2419 if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
2420 rrecs++;
2421 src_index = (lrecs - rrecs + 1);
2422
2423 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2424
2425 /*
2426 * Copy btree block entries from the left block over to the
2427 * new block, the right. Update the right block and log the
2428 * changes.
2429 */
2430 if (level > 0) {
2431 /* It's a non-leaf. Move keys and pointers. */
2432 union xfs_btree_key *lkp; /* left btree key */
2433 union xfs_btree_ptr *lpp; /* left address pointer */
2434 union xfs_btree_key *rkp; /* right btree key */
2435 union xfs_btree_ptr *rpp; /* right address pointer */
2436
2437 lkp = xfs_btree_key_addr(cur, src_index, left);
2438 lpp = xfs_btree_ptr_addr(cur, src_index, left);
2439 rkp = xfs_btree_key_addr(cur, 1, right);
2440 rpp = xfs_btree_ptr_addr(cur, 1, right);
2441
2442#ifdef DEBUG
2443 for (i = src_index; i < rrecs; i++) {
2444 error = xfs_btree_check_ptr(cur, lpp, i, level);
2445 if (error)
2446 goto error0;
2447 }
2448#endif
2449
2450 xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
2451 xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
2452
2453 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2454 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2455
2456 /* Grab the keys to the entries moved to the right block */
2457 xfs_btree_copy_keys(cur, key, rkp, 1);
2458 } else {
2459 /* It's a leaf. Move records. */
2460 union xfs_btree_rec *lrp; /* left record pointer */
2461 union xfs_btree_rec *rrp; /* right record pointer */
2462
2463 lrp = xfs_btree_rec_addr(cur, src_index, left);
2464 rrp = xfs_btree_rec_addr(cur, 1, right);
2465
2466 xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
2467 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2468
2469 cur->bc_ops->init_key_from_rec(key,
2470 xfs_btree_rec_addr(cur, 1, right));
2471 }
2472
2473
2474 /*
2475 * Find the left block number by looking in the buffer.
2476 * Adjust numrecs, sibling pointers.
2477 */
2478 xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
2479 xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
2480 xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2481 xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2482
2483 lrecs -= rrecs;
2484 xfs_btree_set_numrecs(left, lrecs);
2485 xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
2486
2487 xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
2488 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
2489
2490 /*
2491 * If there's a block to the new block's right, make that block
2492 * point back to right instead of to left.
2493 */
2494 if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
0d7409b1 2495 error = xfs_btree_read_buf_block(cur, &rrptr,
f5eb8e7c
CH		 2496 0, &rrblock, &rrbp);
2497 if (error)
2498 goto error0;
2499 xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
2500 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
2501 }
2502 /*
2503 * If the cursor is really in the right block, move it there.
2504 * If it's just pointing past the last entry in left, then we'll
2505 * insert there, so don't change anything in that case.
2506 */
2507 if (cur->bc_ptrs[level] > lrecs + 1) {
2508 xfs_btree_setbuf(cur, level, rbp);
2509 cur->bc_ptrs[level] -= lrecs;
2510 }
2511 /*
2512 * If there are more levels, we'll need another cursor which refers
2513 * the right block, no matter where this cursor was.
2514 */
2515 if (level + 1 < cur->bc_nlevels) {
2516 error = xfs_btree_dup_cursor(cur, curp);
2517 if (error)
2518 goto error0;
2519 (*curp)->bc_ptrs[level + 1]++;
2520 }
2521 *ptrp = rptr;
2522 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2523 *stat = 1;
2524 return 0;
2525out0:
2526 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2527 *stat = 0;
2528 return 0;
2529
2530error0:
2531 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2532 return error;
2533}
344207ce 2534
cf11da9c
DC		 2535struct xfs_btree_split_args {
2536 struct xfs_btree_cur *cur;
2537 int level;
2538 union xfs_btree_ptr *ptrp;
2539 union xfs_btree_key *key;
2540 struct xfs_btree_cur **curp;
2541 int *stat; /* success/failure */
2542 int result;
2543 bool kswapd; /* allocation in kswapd context */
2544 struct completion *done;
2545 struct work_struct work;
2546};
2547
2548/*
2549 * Stack switching interfaces for allocation
2550 */
2551static void
2552xfs_btree_split_worker(
2553 struct work_struct *work)
2554{
2555 struct xfs_btree_split_args *args = container_of(work,
2556 struct xfs_btree_split_args, work);
2557 unsigned long pflags;
2558 unsigned long new_pflags = PF_FSTRANS;
2559
2560 /*
2561 * we are in a transaction context here, but may also be doing work
2562 * in kswapd context, and hence we may need to inherit that state
2563 * temporarily to ensure that we don't block waiting for memory reclaim
2564 * in any way.
2565 */
2566 if (args->kswapd)
2567 new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD;
2568
2569 current_set_flags_nested(&pflags, new_pflags);
2570
2571 args->result = __xfs_btree_split(args->cur, args->level, args->ptrp,
2572 args->key, args->curp, args->stat);
2573 complete(args->done);
2574
2575 current_restore_flags_nested(&pflags, new_pflags);
2576}
2577
2578/*
2579 * BMBT split requests often come in with little stack to work on. Push
2580 * them off to a worker thread so there is lots of stack to use. For the other
2581 * btree types, just call directly to avoid the context switch overhead here.
2582 */
2583STATIC int /* error */
2584xfs_btree_split(
2585 struct xfs_btree_cur *cur,
2586 int level,
2587 union xfs_btree_ptr *ptrp,
2588 union xfs_btree_key *key,
2589 struct xfs_btree_cur **curp,
2590 int *stat) /* success/failure */
2591{
2592 struct xfs_btree_split_args args;
2593 DECLARE_COMPLETION_ONSTACK(done);
2594
2595 if (cur->bc_btnum != XFS_BTNUM_BMAP)
2596 return __xfs_btree_split(cur, level, ptrp, key, curp, stat);
2597
2598 args.cur = cur;
2599 args.level = level;
2600 args.ptrp = ptrp;
2601 args.key = key;
2602 args.curp = curp;
2603 args.stat = stat;
2604 args.done = &done;
2605 args.kswapd = current_is_kswapd();
2606 INIT_WORK_ONSTACK(&args.work, xfs_btree_split_worker);
2607 queue_work(xfs_alloc_wq, &args.work);
2608 wait_for_completion(&done);
2609 destroy_work_on_stack(&args.work);
2610 return args.result;
2611}
2612
2613
ea77b0a6
CH		 2614/*
2615 * Copy the old inode root contents into a real block and make the
2616 * broot point to it.
2617 */
2618int /* error */
2619xfs_btree_new_iroot(
2620 struct xfs_btree_cur *cur, /* btree cursor */
2621 int *logflags, /* logging flags for inode */
2622 int *stat) /* return status - 0 fail */
2623{
2624 struct xfs_buf *cbp; /* buffer for cblock */
2625 struct xfs_btree_block *block; /* btree block */
2626 struct xfs_btree_block *cblock; /* child btree block */
2627 union xfs_btree_key *ckp; /* child key pointer */
2628 union xfs_btree_ptr *cpp; /* child ptr pointer */
2629 union xfs_btree_key *kp; /* pointer to btree key */
2630 union xfs_btree_ptr *pp; /* pointer to block addr */
2631 union xfs_btree_ptr nptr; /* new block addr */
2632 int level; /* btree level */
2633 int error; /* error return code */
2634#ifdef DEBUG
2635 int i; /* loop counter */
2636#endif
2637
2638 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2639 XFS_BTREE_STATS_INC(cur, newroot);
2640
2641 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
2642
2643 level = cur->bc_nlevels - 1;
2644
2645 block = xfs_btree_get_iroot(cur);
2646 pp = xfs_btree_ptr_addr(cur, 1, block);
2647
2648 /* Allocate the new block. If we can't do it, we're toast. Give up. */
6f8950cd 2649 error = cur->bc_ops->alloc_block(cur, pp, &nptr, stat);
ea77b0a6
CH		 2650 if (error)
2651 goto error0;
2652 if (*stat == 0) {
2653 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2654 return 0;
2655 }
2656 XFS_BTREE_STATS_INC(cur, alloc);
2657
2658 /* Copy the root into a real block. */
2659 error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp);
2660 if (error)
2661 goto error0;
2662
088c9f67
DC		 2663 /*
2664 * we can't just memcpy() the root in for CRC enabled btree blocks.
2665 * In that case have to also ensure the blkno remains correct
2666 */
ea77b0a6 2667 memcpy(cblock, block, xfs_btree_block_len(cur));
088c9f67
DC		 2668 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
2669 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
2670 cblock->bb_u.l.bb_blkno = cpu_to_be64(cbp->b_bn);
2671 else
2672 cblock->bb_u.s.bb_blkno = cpu_to_be64(cbp->b_bn);
2673 }
ea77b0a6
CH		 2674
2675 be16_add_cpu(&block->bb_level, 1);
2676 xfs_btree_set_numrecs(block, 1);
2677 cur->bc_nlevels++;
2678 cur->bc_ptrs[level + 1] = 1;
2679
2680 kp = xfs_btree_key_addr(cur, 1, block);
2681 ckp = xfs_btree_key_addr(cur, 1, cblock);
2682 xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock));
2683
2684 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
2685#ifdef DEBUG
2686 for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
2687 error = xfs_btree_check_ptr(cur, pp, i, level);
2688 if (error)
2689 goto error0;
2690 }
2691#endif
2692 xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock));
2693
2694#ifdef DEBUG
2695 error = xfs_btree_check_ptr(cur, &nptr, 0, level);
2696 if (error)
2697 goto error0;
2698#endif
2699 xfs_btree_copy_ptrs(cur, pp, &nptr, 1);
2700
2701 xfs_iroot_realloc(cur->bc_private.b.ip,
2702 1 - xfs_btree_get_numrecs(cblock),
2703 cur->bc_private.b.whichfork);
2704
2705 xfs_btree_setbuf(cur, level, cbp);
2706
2707 /*
2708 * Do all this logging at the end so that
2709 * the root is at the right level.
2710 */
2711 xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS);
2712 xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2713 xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2714
2715 *logflags |=
9d87c319 2716 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork);
ea77b0a6
CH		 2717 *stat = 1;
2718 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2719 return 0;
2720error0:
2721 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2722 return error;
2723}
2724
344207ce
CH		 2725/*
2726 * Allocate a new root block, fill it in.
2727 */
3cc7524c 2728STATIC int /* error */
344207ce
CH		 2729xfs_btree_new_root(
2730 struct xfs_btree_cur *cur, /* btree cursor */
2731 int *stat) /* success/failure */
2732{
2733 struct xfs_btree_block *block; /* one half of the old root block */
2734 struct xfs_buf *bp; /* buffer containing block */
2735 int error; /* error return value */
2736 struct xfs_buf *lbp; /* left buffer pointer */
2737 struct xfs_btree_block *left; /* left btree block */
2738 struct xfs_buf *nbp; /* new (root) buffer */
2739 struct xfs_btree_block *new; /* new (root) btree block */
2740 int nptr; /* new value for key index, 1 or 2 */
2741 struct xfs_buf *rbp; /* right buffer pointer */
2742 struct xfs_btree_block *right; /* right btree block */
2743 union xfs_btree_ptr rptr;
2744 union xfs_btree_ptr lptr;
2745
2746 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2747 XFS_BTREE_STATS_INC(cur, newroot);
2748
2749 /* initialise our start point from the cursor */
2750 cur->bc_ops->init_ptr_from_cur(cur, &rptr);
2751
2752 /* Allocate the new block. If we can't do it, we're toast. Give up. */
6f8950cd 2753 error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, stat);
344207ce
CH		 2754 if (error)
2755 goto error0;
2756 if (*stat == 0)
2757 goto out0;
2758 XFS_BTREE_STATS_INC(cur, alloc);
2759
2760 /* Set up the new block. */
2761 error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp);
2762 if (error)
2763 goto error0;
2764
2765 /* Set the root in the holding structure increasing the level by 1. */
2766 cur->bc_ops->set_root(cur, &lptr, 1);
2767
2768 /*
2769 * At the previous root level there are now two blocks: the old root,
2770 * and the new block generated when it was split. We don't know which
2771 * one the cursor is pointing at, so we set up variables "left" and
2772 * "right" for each case.
2773 */
2774 block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp);
2775
2776#ifdef DEBUG
2777 error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp);
2778 if (error)
2779 goto error0;
2780#endif
2781
2782 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
2783 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
2784 /* Our block is left, pick up the right block. */
2785 lbp = bp;
2786 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2787 left = block;
0d7409b1 2788 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
344207ce
CH		 2789 if (error)
2790 goto error0;
2791 bp = rbp;
2792 nptr = 1;
2793 } else {
2794 /* Our block is right, pick up the left block. */
2795 rbp = bp;
2796 xfs_btree_buf_to_ptr(cur, rbp, &rptr);
2797 right = block;
2798 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
0d7409b1 2799 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
344207ce
CH		 2800 if (error)
2801 goto error0;
2802 bp = lbp;
2803 nptr = 2;
2804 }
2805 /* Fill in the new block's btree header and log it. */
ee1a47ab 2806 xfs_btree_init_block_cur(cur, nbp, cur->bc_nlevels, 2);
344207ce
CH		 2807 xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS);
2808 ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) &&
2809 !xfs_btree_ptr_is_null(cur, &rptr));
2810
2811 /* Fill in the key data in the new root. */
2812 if (xfs_btree_get_level(left) > 0) {
2813 xfs_btree_copy_keys(cur,
2814 xfs_btree_key_addr(cur, 1, new),
2815 xfs_btree_key_addr(cur, 1, left), 1);
2816 xfs_btree_copy_keys(cur,
2817 xfs_btree_key_addr(cur, 2, new),
2818 xfs_btree_key_addr(cur, 1, right), 1);
2819 } else {
2820 cur->bc_ops->init_key_from_rec(
2821 xfs_btree_key_addr(cur, 1, new),
2822 xfs_btree_rec_addr(cur, 1, left));
2823 cur->bc_ops->init_key_from_rec(
2824 xfs_btree_key_addr(cur, 2, new),
2825 xfs_btree_rec_addr(cur, 1, right));
2826 }
2827 xfs_btree_log_keys(cur, nbp, 1, 2);
2828
2829 /* Fill in the pointer data in the new root. */
2830 xfs_btree_copy_ptrs(cur,
2831 xfs_btree_ptr_addr(cur, 1, new), &lptr, 1);
2832 xfs_btree_copy_ptrs(cur,
2833 xfs_btree_ptr_addr(cur, 2, new), &rptr, 1);
2834 xfs_btree_log_ptrs(cur, nbp, 1, 2);
2835
2836 /* Fix up the cursor. */
2837 xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
2838 cur->bc_ptrs[cur->bc_nlevels] = nptr;
2839 cur->bc_nlevels++;
2840 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2841 *stat = 1;
2842 return 0;
2843error0:
2844 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2845 return error;
2846out0:
2847 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2848 *stat = 0;
2849 return 0;
2850}
4b22a571
CH		 2851
2852STATIC int
2853xfs_btree_make_block_unfull(
2854 struct xfs_btree_cur *cur, /* btree cursor */
2855 int level, /* btree level */
2856 int numrecs,/* # of recs in block */
2857 int *oindex,/* old tree index */
2858 int *index, /* new tree index */
2859 union xfs_btree_ptr *nptr, /* new btree ptr */
2860 struct xfs_btree_cur **ncur, /* new btree cursor */
2861 union xfs_btree_rec *nrec, /* new record */
2862 int *stat)
2863{
2864 union xfs_btree_key key; /* new btree key value */
2865 int error = 0;
2866
2867 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2868 level == cur->bc_nlevels - 1) {
2869 struct xfs_inode *ip = cur->bc_private.b.ip;
2870
2871 if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) {
2872 /* A root block that can be made bigger. */
4b22a571
CH		 2873 xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork);
2874 } else {
2875 /* A root block that needs replacing */
2876 int logflags = 0;
2877
2878 error = xfs_btree_new_iroot(cur, &logflags, stat);
2879 if (error || *stat == 0)
2880 return error;
2881
2882 xfs_trans_log_inode(cur->bc_tp, ip, logflags);
2883 }
2884
2885 return 0;
2886 }
2887
2888 /* First, try shifting an entry to the right neighbor. */
2889 error = xfs_btree_rshift(cur, level, stat);
2890 if (error || *stat)
2891 return error;
2892
2893 /* Next, try shifting an entry to the left neighbor. */
2894 error = xfs_btree_lshift(cur, level, stat);
2895 if (error)
2896 return error;
2897
2898 if (*stat) {
2899 *oindex = *index = cur->bc_ptrs[level];
2900 return 0;
2901 }
2902
2903 /*
2904 * Next, try splitting the current block in half.
2905 *
2906 * If this works we have to re-set our variables because we
2907 * could be in a different block now.
2908 */
2909 error = xfs_btree_split(cur, level, nptr, &key, ncur, stat);
2910 if (error || *stat == 0)
2911 return error;
2912
2913
2914 *index = cur->bc_ptrs[level];
2915 cur->bc_ops->init_rec_from_key(&key, nrec);
2916 return 0;
2917}
2918
2919/*
2920 * Insert one record/level. Return information to the caller
2921 * allowing the next level up to proceed if necessary.
2922 */
2923STATIC int
2924xfs_btree_insrec(
2925 struct xfs_btree_cur *cur, /* btree cursor */
2926 int level, /* level to insert record at */
2927 union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
2928 union xfs_btree_rec *recp, /* i/o: record data inserted */
2929 struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
2930 int *stat) /* success/failure */
2931{
2932 struct xfs_btree_block *block; /* btree block */
2933 struct xfs_buf *bp; /* buffer for block */
2934 union xfs_btree_key key; /* btree key */
2935 union xfs_btree_ptr nptr; /* new block ptr */
2936 struct xfs_btree_cur *ncur; /* new btree cursor */
2937 union xfs_btree_rec nrec; /* new record count */
2938 int optr; /* old key/record index */
2939 int ptr; /* key/record index */
2940 int numrecs;/* number of records */
2941 int error; /* error return value */
2942#ifdef DEBUG
2943 int i;
2944#endif
2945
2946 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2947 XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp);
2948
2949 ncur = NULL;
2950
2951 /*
2952 * If we have an external root pointer, and we've made it to the
2953 * root level, allocate a new root block and we're done.
2954 */
2955 if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2956 (level >= cur->bc_nlevels)) {
2957 error = xfs_btree_new_root(cur, stat);
2958 xfs_btree_set_ptr_null(cur, ptrp);
2959
2960 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2961 return error;
2962 }
2963
2964 /* If we're off the left edge, return failure. */
2965 ptr = cur->bc_ptrs[level];
2966 if (ptr == 0) {
2967 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2968 *stat = 0;
2969 return 0;
2970 }
2971
2972 /* Make a key out of the record data to be inserted, and save it. */
2973 cur->bc_ops->init_key_from_rec(&key, recp);
2974
2975 optr = ptr;
2976
2977 XFS_BTREE_STATS_INC(cur, insrec);
2978
2979 /* Get pointers to the btree buffer and block. */
2980 block = xfs_btree_get_block(cur, level, &bp);
2981 numrecs = xfs_btree_get_numrecs(block);
2982
2983#ifdef DEBUG
2984 error = xfs_btree_check_block(cur, block, level, bp);
2985 if (error)
2986 goto error0;
2987
2988 /* Check that the new entry is being inserted in the right place. */
2989 if (ptr <= numrecs) {
2990 if (level == 0) {
4a26e66e
CH		 2991 ASSERT(cur->bc_ops->recs_inorder(cur, recp,
2992 xfs_btree_rec_addr(cur, ptr, block)));
4b22a571 2993 } else {
4a26e66e
CH		 2994 ASSERT(cur->bc_ops->keys_inorder(cur, &key,
2995 xfs_btree_key_addr(cur, ptr, block)));
4b22a571
CH		 2996 }
2997 }
2998#endif
2999
3000 /*
3001 * If the block is full, we can't insert the new entry until we
3002 * make the block un-full.
3003 */
3004 xfs_btree_set_ptr_null(cur, &nptr);
3005 if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
3006 error = xfs_btree_make_block_unfull(cur, level, numrecs,
3007 &optr, &ptr, &nptr, &ncur, &nrec, stat);
3008 if (error || *stat == 0)
3009 goto error0;
3010 }
3011
3012 /*
3013 * The current block may have changed if the block was
3014 * previously full and we have just made space in it.
3015 */
3016 block = xfs_btree_get_block(cur, level, &bp);
3017 numrecs = xfs_btree_get_numrecs(block);
3018
3019#ifdef DEBUG
3020 error = xfs_btree_check_block(cur, block, level, bp);
3021 if (error)
3022 return error;
3023#endif
3024
3025 /*
3026 * At this point we know there's room for our new entry in the block
3027 * we're pointing at.
3028 */
3029 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1);
3030
3031 if (level > 0) {
3032 /* It's a nonleaf. make a hole in the keys and ptrs */
3033 union xfs_btree_key *kp;
3034 union xfs_btree_ptr *pp;
3035
3036 kp = xfs_btree_key_addr(cur, ptr, block);
3037 pp = xfs_btree_ptr_addr(cur, ptr, block);
3038
3039#ifdef DEBUG
3040 for (i = numrecs - ptr; i >= 0; i--) {
3041 error = xfs_btree_check_ptr(cur, pp, i, level);
3042 if (error)
3043 return error;
3044 }
3045#endif
3046
3047 xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1);
3048 xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1);
3049
3050#ifdef DEBUG
3051 error = xfs_btree_check_ptr(cur, ptrp, 0, level);
3052 if (error)
3053 goto error0;
3054#endif
3055
3056 /* Now put the new data in, bump numrecs and log it. */
3057 xfs_btree_copy_keys(cur, kp, &key, 1);
3058 xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
3059 numrecs++;
3060 xfs_btree_set_numrecs(block, numrecs);
3061 xfs_btree_log_ptrs(cur, bp, ptr, numrecs);
3062 xfs_btree_log_keys(cur, bp, ptr, numrecs);
3063#ifdef DEBUG
3064 if (ptr < numrecs) {
4a26e66e
CH		 3065 ASSERT(cur->bc_ops->keys_inorder(cur, kp,
3066 xfs_btree_key_addr(cur, ptr + 1, block)));
4b22a571
CH		 3067 }
3068#endif
3069 } else {
3070 /* It's a leaf. make a hole in the records */
3071 union xfs_btree_rec *rp;
3072
3073 rp = xfs_btree_rec_addr(cur, ptr, block);
3074
3075 xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);
3076
3077 /* Now put the new data in, bump numrecs and log it. */
3078 xfs_btree_copy_recs(cur, rp, recp, 1);
3079 xfs_btree_set_numrecs(block, ++numrecs);
3080 xfs_btree_log_recs(cur, bp, ptr, numrecs);
3081#ifdef DEBUG
3082 if (ptr < numrecs) {
4a26e66e
CH		 3083 ASSERT(cur->bc_ops->recs_inorder(cur, rp,
3084 xfs_btree_rec_addr(cur, ptr + 1, block)));
4b22a571
CH		 3085 }
3086#endif
3087 }
3088
3089 /* Log the new number of records in the btree header. */
3090 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3091
3092 /* If we inserted at the start of a block, update the parents' keys. */
3093 if (optr == 1) {
3094 error = xfs_btree_updkey(cur, &key, level + 1);
3095 if (error)
3096 goto error0;
3097 }
3098
3099 /*
3100 * If we are tracking the last record in the tree and
3101 * we are at the far right edge of the tree, update it.
3102 */
3103 if (xfs_btree_is_lastrec(cur, block, level)) {
3104 cur->bc_ops->update_lastrec(cur, block, recp,
3105 ptr, LASTREC_INSREC);
3106 }
3107
3108 /*
3109 * Return the new block number, if any.
3110 * If there is one, give back a record value and a cursor too.
3111 */
3112 *ptrp = nptr;
3113 if (!xfs_btree_ptr_is_null(cur, &nptr)) {
3114 *recp = nrec;
3115 *curp = ncur;
3116 }
3117
3118 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3119 *stat = 1;
3120 return 0;
3121
3122error0:
3123 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3124 return error;
3125}
3126
3127/*
3128 * Insert the record at the point referenced by cur.
3129 *
3130 * A multi-level split of the tree on insert will invalidate the original
3131 * cursor. All callers of this function should assume that the cursor is
3132 * no longer valid and revalidate it.
3133 */
3134int
3135xfs_btree_insert(
3136 struct xfs_btree_cur *cur,
3137 int *stat)
3138{
3139 int error; /* error return value */
3140 int i; /* result value, 0 for failure */
3141 int level; /* current level number in btree */
3142 union xfs_btree_ptr nptr; /* new block number (split result) */
3143 struct xfs_btree_cur *ncur; /* new cursor (split result) */
3144 struct xfs_btree_cur *pcur; /* previous level's cursor */
3145 union xfs_btree_rec rec; /* record to insert */
3146
3147 level = 0;
3148 ncur = NULL;
3149 pcur = cur;
3150
3151 xfs_btree_set_ptr_null(cur, &nptr);
3152 cur->bc_ops->init_rec_from_cur(cur, &rec);
3153
3154 /*
3155 * Loop going up the tree, starting at the leaf level.
3156 * Stop when we don't get a split block, that must mean that
3157 * the insert is finished with this level.
3158 */
3159 do {
3160 /*
3161 * Insert nrec/nptr into this level of the tree.
3162 * Note if we fail, nptr will be null.
3163 */
3164 error = xfs_btree_insrec(pcur, level, &nptr, &rec, &ncur, &i);
3165 if (error) {
3166 if (pcur != cur)
3167 xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
3168 goto error0;
3169 }
3170
c29aad41 3171 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
4b22a571
CH		 3172 level++;
3173
3174 /*
3175 * See if the cursor we just used is trash.
3176 * Can't trash the caller's cursor, but otherwise we should
3177 * if ncur is a new cursor or we're about to be done.
3178 */
3179 if (pcur != cur &&
3180 (ncur || xfs_btree_ptr_is_null(cur, &nptr))) {
3181 /* Save the state from the cursor before we trash it */
3182 if (cur->bc_ops->update_cursor)
3183 cur->bc_ops->update_cursor(pcur, cur);
3184 cur->bc_nlevels = pcur->bc_nlevels;
3185 xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
3186 }
3187 /* If we got a new cursor, switch to it. */
3188 if (ncur) {
3189 pcur = ncur;
3190 ncur = NULL;
3191 }
3192 } while (!xfs_btree_ptr_is_null(cur, &nptr));
3193
3194 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3195 *stat = i;
3196 return 0;
3197error0:
3198 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3199 return error;
3200}
d4b3a4b7
CH		 3201
3202/*
3203 * Try to merge a non-leaf block back into the inode root.
3204 *
3205 * Note: the killroot names comes from the fact that we're effectively
3206 * killing the old root block. But because we can't just delete the
3207 * inode we have to copy the single block it was pointing to into the
3208 * inode.
3209 */
d96f8f89 3210STATIC int
d4b3a4b7
CH		 3211xfs_btree_kill_iroot(
3212 struct xfs_btree_cur *cur)
3213{
3214 int whichfork = cur->bc_private.b.whichfork;
3215 struct xfs_inode *ip = cur->bc_private.b.ip;
3216 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
3217 struct xfs_btree_block *block;
3218 struct xfs_btree_block *cblock;
3219 union xfs_btree_key *kp;
3220 union xfs_btree_key *ckp;
3221 union xfs_btree_ptr *pp;
3222 union xfs_btree_ptr *cpp;
3223 struct xfs_buf *cbp;
3224 int level;
3225 int index;
3226 int numrecs;
196328ec 3227 int error;
d4b3a4b7
CH		 3228#ifdef DEBUG
3229 union xfs_btree_ptr ptr;
3230 int i;
3231#endif
3232
3233 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3234
3235 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
3236 ASSERT(cur->bc_nlevels > 1);
3237
3238 /*
3239 * Don't deal with the root block needs to be a leaf case.
3240 * We're just going to turn the thing back into extents anyway.
3241 */
3242 level = cur->bc_nlevels - 1;
3243 if (level == 1)
3244 goto out0;
3245
3246 /*
3247 * Give up if the root has multiple children.
3248 */
3249 block = xfs_btree_get_iroot(cur);
3250 if (xfs_btree_get_numrecs(block) != 1)
3251 goto out0;
3252
3253 cblock = xfs_btree_get_block(cur, level - 1, &cbp);
3254 numrecs = xfs_btree_get_numrecs(cblock);
3255
3256 /*
3257 * Only do this if the next level will fit.
3258 * Then the data must be copied up to the inode,
3259 * instead of freeing the root you free the next level.
3260 */
3261 if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level))
3262 goto out0;
3263
3264 XFS_BTREE_STATS_INC(cur, killroot);
3265
3266#ifdef DEBUG
3267 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
3268 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3269 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
3270 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3271#endif
3272
3273 index = numrecs - cur->bc_ops->get_maxrecs(cur, level);
3274 if (index) {
3275 xfs_iroot_realloc(cur->bc_private.b.ip, index,
3276 cur->bc_private.b.whichfork);
7cc95a82 3277 block = ifp->if_broot;
d4b3a4b7
CH		 3278 }
3279
3280 be16_add_cpu(&block->bb_numrecs, index);
3281 ASSERT(block->bb_numrecs == cblock->bb_numrecs);
3282
3283 kp = xfs_btree_key_addr(cur, 1, block);
3284 ckp = xfs_btree_key_addr(cur, 1, cblock);
3285 xfs_btree_copy_keys(cur, kp, ckp, numrecs);
3286
3287 pp = xfs_btree_ptr_addr(cur, 1, block);
3288 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
3289#ifdef DEBUG
3290 for (i = 0; i < numrecs; i++) {
d4b3a4b7
CH		 3291 error = xfs_btree_check_ptr(cur, cpp, i, level - 1);
3292 if (error) {
3293 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3294 return error;
3295 }
3296 }
3297#endif
3298 xfs_btree_copy_ptrs(cur, pp, cpp, numrecs);
3299
c46ee8ad 3300 error = xfs_btree_free_block(cur, cbp);
196328ec
CH		 3301 if (error) {
3302 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3303 return error;
3304 }
d4b3a4b7
CH		 3305
3306 cur->bc_bufs[level - 1] = NULL;
3307 be16_add_cpu(&block->bb_level, -1);
3308 xfs_trans_log_inode(cur->bc_tp, ip,
9d87c319 3309 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork));
d4b3a4b7
CH		 3310 cur->bc_nlevels--;
3311out0:
3312 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3313 return 0;
3314}
91cca5df 3315
c0e59e1a
CH		 3316/*
3317 * Kill the current root node, and replace it with it's only child node.
3318 */
3319STATIC int
3320xfs_btree_kill_root(
3321 struct xfs_btree_cur *cur,
3322 struct xfs_buf *bp,
3323 int level,
3324 union xfs_btree_ptr *newroot)
3325{
3326 int error;
3327
3328 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3329 XFS_BTREE_STATS_INC(cur, killroot);
3330
3331 /*
3332 * Update the root pointer, decreasing the level by 1 and then
3333 * free the old root.
3334 */
3335 cur->bc_ops->set_root(cur, newroot, -1);
3336
c46ee8ad 3337 error = xfs_btree_free_block(cur, bp);
c0e59e1a
CH		 3338 if (error) {
3339 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3340 return error;
3341 }
3342
c0e59e1a
CH		 3343 cur->bc_bufs[level] = NULL;
3344 cur->bc_ra[level] = 0;
3345 cur->bc_nlevels--;
3346
3347 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3348 return 0;
3349}
3350
91cca5df
CH		 3351STATIC int
3352xfs_btree_dec_cursor(
3353 struct xfs_btree_cur *cur,
3354 int level,
3355 int *stat)
3356{
3357 int error;
3358 int i;
3359
3360 if (level > 0) {
3361 error = xfs_btree_decrement(cur, level, &i);
3362 if (error)
3363 return error;
3364 }
3365
3366 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3367 *stat = 1;
3368 return 0;
3369}
3370
3371/*
3372 * Single level of the btree record deletion routine.
3373 * Delete record pointed to by cur/level.
3374 * Remove the record from its block then rebalance the tree.
3375 * Return 0 for error, 1 for done, 2 to go on to the next level.
3376 */
3377STATIC int /* error */
3378xfs_btree_delrec(
3379 struct xfs_btree_cur *cur, /* btree cursor */
3380 int level, /* level removing record from */
3381 int *stat) /* fail/done/go-on */
3382{
3383 struct xfs_btree_block *block; /* btree block */
3384 union xfs_btree_ptr cptr; /* current block ptr */
3385 struct xfs_buf *bp; /* buffer for block */
3386 int error; /* error return value */
3387 int i; /* loop counter */
3388 union xfs_btree_key key; /* storage for keyp */
3389 union xfs_btree_key *keyp = &key; /* passed to the next level */
3390 union xfs_btree_ptr lptr; /* left sibling block ptr */
3391 struct xfs_buf *lbp; /* left buffer pointer */
3392 struct xfs_btree_block *left; /* left btree block */
3393 int lrecs = 0; /* left record count */
3394 int ptr; /* key/record index */
3395 union xfs_btree_ptr rptr; /* right sibling block ptr */
3396 struct xfs_buf *rbp; /* right buffer pointer */
3397 struct xfs_btree_block *right; /* right btree block */
3398 struct xfs_btree_block *rrblock; /* right-right btree block */
3399 struct xfs_buf *rrbp; /* right-right buffer pointer */
3400 int rrecs = 0; /* right record count */
3401 struct xfs_btree_cur *tcur; /* temporary btree cursor */
3402 int numrecs; /* temporary numrec count */
3403
3404 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3405 XFS_BTREE_TRACE_ARGI(cur, level);
3406
3407 tcur = NULL;
3408
3409 /* Get the index of the entry being deleted, check for nothing there. */
3410 ptr = cur->bc_ptrs[level];
3411 if (ptr == 0) {
3412 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3413 *stat = 0;
3414 return 0;
3415 }
3416
3417 /* Get the buffer & block containing the record or key/ptr. */
3418 block = xfs_btree_get_block(cur, level, &bp);
3419 numrecs = xfs_btree_get_numrecs(block);
3420
3421#ifdef DEBUG
3422 error = xfs_btree_check_block(cur, block, level, bp);
3423 if (error)
3424 goto error0;
3425#endif
3426
3427 /* Fail if we're off the end of the block. */
3428 if (ptr > numrecs) {
3429 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3430 *stat = 0;
3431 return 0;
3432 }
3433
3434 XFS_BTREE_STATS_INC(cur, delrec);
3435 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr);
3436
3437 /* Excise the entries being deleted. */
3438 if (level > 0) {
3439 /* It's a nonleaf. operate on keys and ptrs */
3440 union xfs_btree_key *lkp;
3441 union xfs_btree_ptr *lpp;
3442
3443 lkp = xfs_btree_key_addr(cur, ptr + 1, block);
3444 lpp = xfs_btree_ptr_addr(cur, ptr + 1, block);
3445
3446#ifdef DEBUG
3447 for (i = 0; i < numrecs - ptr; i++) {
3448 error = xfs_btree_check_ptr(cur, lpp, i, level);
3449 if (error)
3450 goto error0;
3451 }
3452#endif
3453
3454 if (ptr < numrecs) {
3455 xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr);
3456 xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr);
3457 xfs_btree_log_keys(cur, bp, ptr, numrecs - 1);
3458 xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1);
3459 }
3460
3461 /*
3462 * If it's the first record in the block, we'll need to pass a
3463 * key up to the next level (updkey).
3464 */
3465 if (ptr == 1)
3466 keyp = xfs_btree_key_addr(cur, 1, block);
3467 } else {
3468 /* It's a leaf. operate on records */
3469 if (ptr < numrecs) {
3470 xfs_btree_shift_recs(cur,
3471 xfs_btree_rec_addr(cur, ptr + 1, block),
3472 -1, numrecs - ptr);
3473 xfs_btree_log_recs(cur, bp, ptr, numrecs - 1);
3474 }
3475
3476 /*
3477 * If it's the first record in the block, we'll need a key
3478 * structure to pass up to the next level (updkey).
3479 */
3480 if (ptr == 1) {
3481 cur->bc_ops->init_key_from_rec(&key,
3482 xfs_btree_rec_addr(cur, 1, block));
3483 keyp = &key;
3484 }
3485 }
3486
3487 /*
3488 * Decrement and log the number of entries in the block.
3489 */
3490 xfs_btree_set_numrecs(block, --numrecs);
3491 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3492
3493 /*
3494 * If we are tracking the last record in the tree and
3495 * we are at the far right edge of the tree, update it.
3496 */
3497 if (xfs_btree_is_lastrec(cur, block, level)) {
3498 cur->bc_ops->update_lastrec(cur, block, NULL,
3499 ptr, LASTREC_DELREC);
3500 }
3501
3502 /*
3503 * We're at the root level. First, shrink the root block in-memory.
3504 * Try to get rid of the next level down. If we can't then there's
3505 * nothing left to do.
3506 */
3507 if (level == cur->bc_nlevels - 1) {
3508 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3509 xfs_iroot_realloc(cur->bc_private.b.ip, -1,
3510 cur->bc_private.b.whichfork);
3511
3512 error = xfs_btree_kill_iroot(cur);
3513 if (error)
3514 goto error0;
3515
3516 error = xfs_btree_dec_cursor(cur, level, stat);
3517 if (error)
3518 goto error0;
3519 *stat = 1;
3520 return 0;
3521 }
3522
3523 /*
3524 * If this is the root level, and there's only one entry left,
3525 * and it's NOT the leaf level, then we can get rid of this
3526 * level.
3527 */
3528 if (numrecs == 1 && level > 0) {
3529 union xfs_btree_ptr *pp;
3530 /*
3531 * pp is still set to the first pointer in the block.
3532 * Make it the new root of the btree.
3533 */
3534 pp = xfs_btree_ptr_addr(cur, 1, block);
c0e59e1a 3535 error = xfs_btree_kill_root(cur, bp, level, pp);
91cca5df
CH		 3536 if (error)
3537 goto error0;
3538 } else if (level > 0) {
3539 error = xfs_btree_dec_cursor(cur, level, stat);
3540 if (error)
3541 goto error0;
3542 }
3543 *stat = 1;
3544 return 0;
3545 }
3546
3547 /*
3548 * If we deleted the leftmost entry in the block, update the
3549 * key values above us in the tree.
3550 */
3551 if (ptr == 1) {
3552 error = xfs_btree_updkey(cur, keyp, level + 1);
3553 if (error)
3554 goto error0;
3555 }
3556
3557 /*
3558 * If the number of records remaining in the block is at least
3559 * the minimum, we're done.
3560 */
3561 if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) {
3562 error = xfs_btree_dec_cursor(cur, level, stat);
3563 if (error)
3564 goto error0;
3565 return 0;
3566 }
3567
3568 /*
3569 * Otherwise, we have to move some records around to keep the
3570 * tree balanced. Look at the left and right sibling blocks to
3571 * see if we can re-balance by moving only one record.
3572 */
3573 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3574 xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB);
3575
3576 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3577 /*
3578 * One child of root, need to get a chance to copy its contents
3579 * into the root and delete it. Can't go up to next level,
3580 * there's nothing to delete there.
3581 */
3582 if (xfs_btree_ptr_is_null(cur, &rptr) &&
3583 xfs_btree_ptr_is_null(cur, &lptr) &&
3584 level == cur->bc_nlevels - 2) {
3585 error = xfs_btree_kill_iroot(cur);
3586 if (!error)
3587 error = xfs_btree_dec_cursor(cur, level, stat);
3588 if (error)
3589 goto error0;
3590 return 0;
3591 }
3592 }
3593
3594 ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) ||
3595 !xfs_btree_ptr_is_null(cur, &lptr));
3596
3597 /*
3598 * Duplicate the cursor so our btree manipulations here won't
3599 * disrupt the next level up.
3600 */
3601 error = xfs_btree_dup_cursor(cur, &tcur);
3602 if (error)
3603 goto error0;
3604
3605 /*
3606 * If there's a right sibling, see if it's ok to shift an entry
3607 * out of it.
3608 */
3609 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3610 /*
3611 * Move the temp cursor to the last entry in the next block.
3612 * Actually any entry but the first would suffice.
3613 */
3614 i = xfs_btree_lastrec(tcur, level);
c29aad41 3615 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
91cca5df
CH		 3616
3617 error = xfs_btree_increment(tcur, level, &i);
3618 if (error)
3619 goto error0;
c29aad41 3620 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
91cca5df
CH		 3621
3622 i = xfs_btree_lastrec(tcur, level);
c29aad41 3623 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
91cca5df
CH		 3624
3625 /* Grab a pointer to the block. */
3626 right = xfs_btree_get_block(tcur, level, &rbp);
3627#ifdef DEBUG
3628 error = xfs_btree_check_block(tcur, right, level, rbp);
3629 if (error)
3630 goto error0;
3631#endif
3632 /* Grab the current block number, for future use. */
3633 xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB);
3634
3635 /*
3636 * If right block is full enough so that removing one entry
3637 * won't make it too empty, and left-shifting an entry out
3638 * of right to us works, we're done.
3639 */
3640 if (xfs_btree_get_numrecs(right) - 1 >=
3641 cur->bc_ops->get_minrecs(tcur, level)) {
3642 error = xfs_btree_lshift(tcur, level, &i);
3643 if (error)
3644 goto error0;
3645 if (i) {
3646 ASSERT(xfs_btree_get_numrecs(block) >=
3647 cur->bc_ops->get_minrecs(tcur, level));
3648
3649 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3650 tcur = NULL;
3651
3652 error = xfs_btree_dec_cursor(cur, level, stat);
3653 if (error)
3654 goto error0;
3655 return 0;
3656 }
3657 }
3658
3659 /*
3660 * Otherwise, grab the number of records in right for
3661 * future reference, and fix up the temp cursor to point
3662 * to our block again (last record).
3663 */
3664 rrecs = xfs_btree_get_numrecs(right);
3665 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3666 i = xfs_btree_firstrec(tcur, level);
c29aad41 3667 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
91cca5df
CH		 3668
3669 error = xfs_btree_decrement(tcur, level, &i);
3670 if (error)
3671 goto error0;
c29aad41 3672 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
91cca5df
CH		 3673 }
3674 }
3675
3676 /*
3677 * If there's a left sibling, see if it's ok to shift an entry
3678 * out of it.
3679 */
3680 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3681 /*
3682 * Move the temp cursor to the first entry in the
3683 * previous block.
3684 */
3685 i = xfs_btree_firstrec(tcur, level);
c29aad41 3686 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
91cca5df
CH		 3687
3688 error = xfs_btree_decrement(tcur, level, &i);
3689 if (error)
3690 goto error0;
3691 i = xfs_btree_firstrec(tcur, level);
c29aad41 3692 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
91cca5df
CH		 3693
3694 /* Grab a pointer to the block. */
3695 left = xfs_btree_get_block(tcur, level, &lbp);
3696#ifdef DEBUG
3697 error = xfs_btree_check_block(cur, left, level, lbp);
3698 if (error)
3699 goto error0;
3700#endif
3701 /* Grab the current block number, for future use. */
3702 xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB);
3703
3704 /*
3705 * If left block is full enough so that removing one entry
3706 * won't make it too empty, and right-shifting an entry out
3707 * of left to us works, we're done.
3708 */
3709 if (xfs_btree_get_numrecs(left) - 1 >=
3710 cur->bc_ops->get_minrecs(tcur, level)) {
3711 error = xfs_btree_rshift(tcur, level, &i);
3712 if (error)
3713 goto error0;
3714 if (i) {
3715 ASSERT(xfs_btree_get_numrecs(block) >=
3716 cur->bc_ops->get_minrecs(tcur, level));
3717 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3718 tcur = NULL;
3719 if (level == 0)
3720 cur->bc_ptrs[0]++;
3721 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3722 *stat = 1;
3723 return 0;
3724 }
3725 }
3726
3727 /*
3728 * Otherwise, grab the number of records in right for
3729 * future reference.
3730 */
3731 lrecs = xfs_btree_get_numrecs(left);
3732 }
3733
3734 /* Delete the temp cursor, we're done with it. */
3735 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3736 tcur = NULL;
3737
3738 /* If here, we need to do a join to keep the tree balanced. */
3739 ASSERT(!xfs_btree_ptr_is_null(cur, &cptr));
3740
3741 if (!xfs_btree_ptr_is_null(cur, &lptr) &&
3742 lrecs + xfs_btree_get_numrecs(block) <=
3743 cur->bc_ops->get_maxrecs(cur, level)) {
3744 /*
3745 * Set "right" to be the starting block,
3746 * "left" to be the left neighbor.
3747 */
3748 rptr = cptr;
3749 right = block;
3750 rbp = bp;
0d7409b1 3751 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
91cca5df
CH		 3752 if (error)
3753 goto error0;
3754
3755 /*
3756 * If that won't work, see if we can join with the right neighbor block.
3757 */
3758 } else if (!xfs_btree_ptr_is_null(cur, &rptr) &&
3759 rrecs + xfs_btree_get_numrecs(block) <=
3760 cur->bc_ops->get_maxrecs(cur, level)) {
3761 /*
3762 * Set "left" to be the starting block,
3763 * "right" to be the right neighbor.
3764 */
3765 lptr = cptr;
3766 left = block;
3767 lbp = bp;
0d7409b1 3768 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
91cca5df
CH		 3769 if (error)
3770 goto error0;
3771
3772 /*
3773 * Otherwise, we can't fix the imbalance.
3774 * Just return. This is probably a logic error, but it's not fatal.
3775 */
3776 } else {
3777 error = xfs_btree_dec_cursor(cur, level, stat);
3778 if (error)
3779 goto error0;
3780 return 0;
3781 }
3782
3783 rrecs = xfs_btree_get_numrecs(right);
3784 lrecs = xfs_btree_get_numrecs(left);
3785
3786 /*
3787 * We're now going to join "left" and "right" by moving all the stuff
3788 * in "right" to "left" and deleting "right".
3789 */
3790 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
3791 if (level > 0) {
3792 /* It's a non-leaf. Move keys and pointers. */
3793 union xfs_btree_key *lkp; /* left btree key */
3794 union xfs_btree_ptr *lpp; /* left address pointer */
3795 union xfs_btree_key *rkp; /* right btree key */
3796 union xfs_btree_ptr *rpp; /* right address pointer */
3797
3798 lkp = xfs_btree_key_addr(cur, lrecs + 1, left);
3799 lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left);
3800 rkp = xfs_btree_key_addr(cur, 1, right);
3801 rpp = xfs_btree_ptr_addr(cur, 1, right);
3802#ifdef DEBUG
3803 for (i = 1; i < rrecs; i++) {
3804 error = xfs_btree_check_ptr(cur, rpp, i, level);
3805 if (error)
3806 goto error0;
3807 }
3808#endif
3809 xfs_btree_copy_keys(cur, lkp, rkp, rrecs);
3810 xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs);
3811
3812 xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
3813 xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
3814 } else {
3815 /* It's a leaf. Move records. */
3816 union xfs_btree_rec *lrp; /* left record pointer */
3817 union xfs_btree_rec *rrp; /* right record pointer */
3818
3819 lrp = xfs_btree_rec_addr(cur, lrecs + 1, left);
3820 rrp = xfs_btree_rec_addr(cur, 1, right);
3821
3822 xfs_btree_copy_recs(cur, lrp, rrp, rrecs);
3823 xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
3824 }
3825
3826 XFS_BTREE_STATS_INC(cur, join);
3827
3828 /*
9da096fd 3829 * Fix up the number of records and right block pointer in the
91cca5df
CH		 3830 * surviving block, and log it.
3831 */
3832 xfs_btree_set_numrecs(left, lrecs + rrecs);
3833 xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB),
3834 xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3835 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
3836
3837 /* If there is a right sibling, point it to the remaining block. */
3838 xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3839 if (!xfs_btree_ptr_is_null(cur, &cptr)) {
0d7409b1 3840 error = xfs_btree_read_buf_block(cur, &cptr, 0, &rrblock, &rrbp);
91cca5df
CH		 3841 if (error)
3842 goto error0;
3843 xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB);
3844 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
3845 }
3846
3847 /* Free the deleted block. */
c46ee8ad 3848 error = xfs_btree_free_block(cur, rbp);
91cca5df
CH		 3849 if (error)
3850 goto error0;
91cca5df
CH		 3851
3852 /*
3853 * If we joined with the left neighbor, set the buffer in the
3854 * cursor to the left block, and fix up the index.
3855 */
3856 if (bp != lbp) {
3857 cur->bc_bufs[level] = lbp;
3858 cur->bc_ptrs[level] += lrecs;
3859 cur->bc_ra[level] = 0;
3860 }
3861 /*
3862 * If we joined with the right neighbor and there's a level above
3863 * us, increment the cursor at that level.
3864 */
3865 else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) ||
3866 (level + 1 < cur->bc_nlevels)) {
3867 error = xfs_btree_increment(cur, level + 1, &i);
3868 if (error)
3869 goto error0;
3870 }
3871
3872 /*
3873 * Readjust the ptr at this level if it's not a leaf, since it's
3874 * still pointing at the deletion point, which makes the cursor
3875 * inconsistent. If this makes the ptr 0, the caller fixes it up.
3876 * We can't use decrement because it would change the next level up.
3877 */
3878 if (level > 0)
3879 cur->bc_ptrs[level]--;
3880
3881 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3882 /* Return value means the next level up has something to do. */
3883 *stat = 2;
3884 return 0;
3885
3886error0:
3887 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3888 if (tcur)
3889 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
3890 return error;
3891}
3892
3893/*
3894 * Delete the record pointed to by cur.
3895 * The cursor refers to the place where the record was (could be inserted)
3896 * when the operation returns.
3897 */
3898int /* error */
3899xfs_btree_delete(
3900 struct xfs_btree_cur *cur,
3901 int *stat) /* success/failure */
3902{
3903 int error; /* error return value */
3904 int level;
3905 int i;
3906
3907 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3908
3909 /*
3910 * Go up the tree, starting at leaf level.
3911 *
3912 * If 2 is returned then a join was done; go to the next level.
3913 * Otherwise we are done.
3914 */
3915 for (level = 0, i = 2; i == 2; level++) {
3916 error = xfs_btree_delrec(cur, level, &i);
3917 if (error)
3918 goto error0;
3919 }
3920
3921 if (i == 0) {
3922 for (level = 1; level < cur->bc_nlevels; level++) {
3923 if (cur->bc_ptrs[level] == 0) {
3924 error = xfs_btree_decrement(cur, level, &i);
3925 if (error)
3926 goto error0;
3927 break;
3928 }
3929 }
3930 }
3931
3932 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3933 *stat = i;
3934 return 0;
3935error0:
3936 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3937 return error;
3938}
8cc938fe
CH		 3939
3940/*
3941 * Get the data from the pointed-to record.
3942 */
3943int /* error */
3944xfs_btree_get_rec(
3945 struct xfs_btree_cur *cur, /* btree cursor */
3946 union xfs_btree_rec **recp, /* output: btree record */
3947 int *stat) /* output: success/failure */
3948{
3949 struct xfs_btree_block *block; /* btree block */
3950 struct xfs_buf *bp; /* buffer pointer */
3951 int ptr; /* record number */
3952#ifdef DEBUG
3953 int error; /* error return value */
3954#endif
3955
3956 ptr = cur->bc_ptrs[0];
3957 block = xfs_btree_get_block(cur, 0, &bp);
3958
3959#ifdef DEBUG
3960 error = xfs_btree_check_block(cur, block, 0, bp);
3961 if (error)
3962 return error;
3963#endif
3964
3965 /*
3966 * Off the right end or left end, return failure.
3967 */
3968 if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
3969 *stat = 0;
3970 return 0;
3971 }
3972
3973 /*
3974 * Point to the record and extract its data.
3975 */
3976 *recp = xfs_btree_rec_addr(cur, ptr, block);
3977 *stat = 1;
3978 return 0;
3979}
21b5c978
DC		 3980
3981/*
3982 * Change the owner of a btree.
3983 *
3984 * The mechanism we use here is ordered buffer logging. Because we don't know
3985 * how many buffers were are going to need to modify, we don't really want to
3986 * have to make transaction reservations for the worst case of every buffer in a
3987 * full size btree as that may be more space that we can fit in the log....
3988 *
3989 * We do the btree walk in the most optimal manner possible - we have sibling
3990 * pointers so we can just walk all the blocks on each level from left to right
3991 * in a single pass, and then move to the next level and do the same. We can
3992 * also do readahead on the sibling pointers to get IO moving more quickly,
3993 * though for slow disks this is unlikely to make much difference to performance
3994 * as the amount of CPU work we have to do before moving to the next block is
3995 * relatively small.
3996 *
3997 * For each btree block that we load, modify the owner appropriately, set the
3998 * buffer as an ordered buffer and log it appropriately. We need to ensure that
3999 * we mark the region we change dirty so that if the buffer is relogged in
4000 * a subsequent transaction the changes we make here as an ordered buffer are
638f4416
DC		 4001 * correctly relogged in that transaction. If we are in recovery context, then
4002 * just queue the modified buffer as delayed write buffer so the transaction
4003 * recovery completion writes the changes to disk.
21b5c978
DC		 4004 */
4005static int
4006xfs_btree_block_change_owner(
4007 struct xfs_btree_cur *cur,
4008 int level,
638f4416
DC		 4009 __uint64_t new_owner,
4010 struct list_head *buffer_list)
21b5c978
DC		 4011{
4012 struct xfs_btree_block *block;
4013 struct xfs_buf *bp;
4014 union xfs_btree_ptr rptr;
4015
4016 /* do right sibling readahead */
4017 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
4018
4019 /* modify the owner */
4020 block = xfs_btree_get_block(cur, level, &bp);
4021 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
4022 block->bb_u.l.bb_owner = cpu_to_be64(new_owner);
4023 else
4024 block->bb_u.s.bb_owner = cpu_to_be32(new_owner);
4025
4026 /*
638f4416
DC		 4027 * If the block is a root block hosted in an inode, we might not have a
4028 * buffer pointer here and we shouldn't attempt to log the change as the
4029 * information is already held in the inode and discarded when the root
4030 * block is formatted into the on-disk inode fork. We still change it,
4031 * though, so everything is consistent in memory.
21b5c978
DC		 4032 */
4033 if (bp) {
638f4416
DC		 4034 if (cur->bc_tp) {
4035 xfs_trans_ordered_buf(cur->bc_tp, bp);
4036 xfs_btree_log_block(cur, bp, XFS_BB_OWNER);
4037 } else {
4038 xfs_buf_delwri_queue(bp, buffer_list);
4039 }
21b5c978
DC		 4040 } else {
4041 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
4042 ASSERT(level == cur->bc_nlevels - 1);
4043 }
4044
4045 /* now read rh sibling block for next iteration */
4046 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
4047 if (xfs_btree_ptr_is_null(cur, &rptr))
2451337d 4048 return -ENOENT;
21b5c978
DC		 4049
4050 return xfs_btree_lookup_get_block(cur, level, &rptr, &block);
4051}
4052
4053int
4054xfs_btree_change_owner(
4055 struct xfs_btree_cur *cur,
638f4416
DC		 4056 __uint64_t new_owner,
4057 struct list_head *buffer_list)
21b5c978
DC		 4058{
4059 union xfs_btree_ptr lptr;
4060 int level;
4061 struct xfs_btree_block *block = NULL;
4062 int error = 0;
4063
4064 cur->bc_ops->init_ptr_from_cur(cur, &lptr);
4065
4066 /* for each level */
4067 for (level = cur->bc_nlevels - 1; level >= 0; level--) {
4068 /* grab the left hand block */
4069 error = xfs_btree_lookup_get_block(cur, level, &lptr, &block);
4070 if (error)
4071 return error;
4072
4073 /* readahead the left most block for the next level down */
4074 if (level > 0) {
4075 union xfs_btree_ptr *ptr;
4076
4077 ptr = xfs_btree_ptr_addr(cur, 1, block);
4078 xfs_btree_readahead_ptr(cur, ptr, 1);
4079
4080 /* save for the next iteration of the loop */
4081 lptr = *ptr;
4082 }
4083
4084 /* for each buffer in the level */
4085 do {
4086 error = xfs_btree_block_change_owner(cur, level,
638f4416
DC		 4087 new_owner,
4088 buffer_list);
21b5c978
DC		 4089 } while (!error);
4090
2451337d 4091 if (error != -ENOENT)
21b5c978
DC		 4092 return error;
4093 }
4094
4095 return 0;
4096}
c5ab131b
DW		 4097
4098/**
4099 * xfs_btree_sblock_v5hdr_verify() -- verify the v5 fields of a short-format
4100 * btree block
4101 *
4102 * @bp: buffer containing the btree block
4103 * @max_recs: pointer to the m_*_mxr max records field in the xfs mount
4104 * @pag_max_level: pointer to the per-ag max level field
4105 */
4106bool
4107xfs_btree_sblock_v5hdr_verify(
4108 struct xfs_buf *bp)
4109{
4110 struct xfs_mount *mp = bp->b_target->bt_mount;
4111 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
4112 struct xfs_perag *pag = bp->b_pag;
4113
4114 if (!xfs_sb_version_hascrc(&mp->m_sb))
4115 return false;
4116 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid))
4117 return false;
4118 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
4119 return false;
4120 if (pag && be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
4121 return false;
4122 return true;
4123}
4124
4125/**
4126 * xfs_btree_sblock_verify() -- verify a short-format btree block
4127 *
4128 * @bp: buffer containing the btree block
4129 * @max_recs: maximum records allowed in this btree node
4130 */
4131bool
4132xfs_btree_sblock_verify(
4133 struct xfs_buf *bp,
4134 unsigned int max_recs)
4135{
4136 struct xfs_mount *mp = bp->b_target->bt_mount;
4137 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
4138
4139 /* numrecs verification */
4140 if (be16_to_cpu(block->bb_numrecs) > max_recs)
4141 return false;
4142
4143 /* sibling pointer verification */
4144 if (!block->bb_u.s.bb_leftsib ||
4145 (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
4146 block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
4147 return false;
4148 if (!block->bb_u.s.bb_rightsib ||
4149 (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
4150 block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
4151 return false;
4152
4153 return true;
4154}
Linux kernel - Deliverables
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