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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" |
1da177e4 | 20 | #include "xfs_types.h" |
a844f451 | 21 | #include "xfs_bit.h" |
1da177e4 | 22 | #include "xfs_log.h" |
a844f451 | 23 | #include "xfs_inum.h" |
1da177e4 LT |
24 | #include "xfs_trans.h" |
25 | #include "xfs_sb.h" | |
26 | #include "xfs_ag.h" | |
1da177e4 LT |
27 | #include "xfs_dir2.h" |
28 | #include "xfs_dmapi.h" | |
29 | #include "xfs_mount.h" | |
1da177e4 | 30 | #include "xfs_bmap_btree.h" |
a844f451 | 31 | #include "xfs_alloc_btree.h" |
1da177e4 | 32 | #include "xfs_ialloc_btree.h" |
1da177e4 | 33 | #include "xfs_dir2_sf.h" |
a844f451 | 34 | #include "xfs_attr_sf.h" |
1da177e4 LT |
35 | #include "xfs_dinode.h" |
36 | #include "xfs_inode.h" | |
a844f451 | 37 | #include "xfs_btree.h" |
637aa50f | 38 | #include "xfs_btree_trace.h" |
a844f451 | 39 | #include "xfs_ialloc.h" |
1da177e4 LT |
40 | #include "xfs_error.h" |
41 | ||
42 | /* | |
43 | * Cursor allocation zone. | |
44 | */ | |
45 | kmem_zone_t *xfs_btree_cur_zone; | |
46 | ||
47 | /* | |
48 | * Btree magic numbers. | |
49 | */ | |
cdcf4333 | 50 | const __uint32_t xfs_magics[XFS_BTNUM_MAX] = { |
1da177e4 LT |
51 | XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC |
52 | }; | |
53 | ||
1da177e4 LT |
54 | /* |
55 | * External routines. | |
56 | */ | |
57 | ||
58 | #ifdef DEBUG | |
1da177e4 LT |
59 | /* |
60 | * Debug routine: check that keys are in the right order. | |
61 | */ | |
62 | void | |
63 | xfs_btree_check_key( | |
64 | xfs_btnum_t btnum, /* btree identifier */ | |
65 | void *ak1, /* pointer to left (lower) key */ | |
66 | void *ak2) /* pointer to right (higher) key */ | |
67 | { | |
68 | switch (btnum) { | |
69 | case XFS_BTNUM_BNO: { | |
70 | xfs_alloc_key_t *k1; | |
71 | xfs_alloc_key_t *k2; | |
72 | ||
73 | k1 = ak1; | |
74 | k2 = ak2; | |
16259e7d | 75 | ASSERT(be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock)); |
1da177e4 LT |
76 | break; |
77 | } | |
78 | case XFS_BTNUM_CNT: { | |
79 | xfs_alloc_key_t *k1; | |
80 | xfs_alloc_key_t *k2; | |
81 | ||
82 | k1 = ak1; | |
83 | k2 = ak2; | |
16259e7d CH |
84 | ASSERT(be32_to_cpu(k1->ar_blockcount) < be32_to_cpu(k2->ar_blockcount) || |
85 | (k1->ar_blockcount == k2->ar_blockcount && | |
86 | be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock))); | |
1da177e4 LT |
87 | break; |
88 | } | |
89 | case XFS_BTNUM_BMAP: { | |
90 | xfs_bmbt_key_t *k1; | |
91 | xfs_bmbt_key_t *k2; | |
92 | ||
93 | k1 = ak1; | |
94 | k2 = ak2; | |
8801bb99 | 95 | ASSERT(be64_to_cpu(k1->br_startoff) < be64_to_cpu(k2->br_startoff)); |
1da177e4 LT |
96 | break; |
97 | } | |
98 | case XFS_BTNUM_INO: { | |
99 | xfs_inobt_key_t *k1; | |
100 | xfs_inobt_key_t *k2; | |
101 | ||
102 | k1 = ak1; | |
103 | k2 = ak2; | |
61a25848 | 104 | ASSERT(be32_to_cpu(k1->ir_startino) < be32_to_cpu(k2->ir_startino)); |
1da177e4 LT |
105 | break; |
106 | } | |
107 | default: | |
108 | ASSERT(0); | |
109 | } | |
110 | } | |
1da177e4 | 111 | |
1da177e4 LT |
112 | /* |
113 | * Debug routine: check that records are in the right order. | |
114 | */ | |
115 | void | |
116 | xfs_btree_check_rec( | |
117 | xfs_btnum_t btnum, /* btree identifier */ | |
118 | void *ar1, /* pointer to left (lower) record */ | |
119 | void *ar2) /* pointer to right (higher) record */ | |
120 | { | |
121 | switch (btnum) { | |
122 | case XFS_BTNUM_BNO: { | |
123 | xfs_alloc_rec_t *r1; | |
124 | xfs_alloc_rec_t *r2; | |
125 | ||
126 | r1 = ar1; | |
127 | r2 = ar2; | |
16259e7d CH |
128 | ASSERT(be32_to_cpu(r1->ar_startblock) + |
129 | be32_to_cpu(r1->ar_blockcount) <= | |
130 | be32_to_cpu(r2->ar_startblock)); | |
1da177e4 LT |
131 | break; |
132 | } | |
133 | case XFS_BTNUM_CNT: { | |
134 | xfs_alloc_rec_t *r1; | |
135 | xfs_alloc_rec_t *r2; | |
136 | ||
137 | r1 = ar1; | |
138 | r2 = ar2; | |
16259e7d CH |
139 | ASSERT(be32_to_cpu(r1->ar_blockcount) < be32_to_cpu(r2->ar_blockcount) || |
140 | (r1->ar_blockcount == r2->ar_blockcount && | |
141 | be32_to_cpu(r1->ar_startblock) < be32_to_cpu(r2->ar_startblock))); | |
1da177e4 LT |
142 | break; |
143 | } | |
144 | case XFS_BTNUM_BMAP: { | |
145 | xfs_bmbt_rec_t *r1; | |
146 | xfs_bmbt_rec_t *r2; | |
147 | ||
148 | r1 = ar1; | |
149 | r2 = ar2; | |
150 | ASSERT(xfs_bmbt_disk_get_startoff(r1) + | |
151 | xfs_bmbt_disk_get_blockcount(r1) <= | |
152 | xfs_bmbt_disk_get_startoff(r2)); | |
153 | break; | |
154 | } | |
155 | case XFS_BTNUM_INO: { | |
156 | xfs_inobt_rec_t *r1; | |
157 | xfs_inobt_rec_t *r2; | |
158 | ||
159 | r1 = ar1; | |
160 | r2 = ar2; | |
61a25848 CH |
161 | ASSERT(be32_to_cpu(r1->ir_startino) + XFS_INODES_PER_CHUNK <= |
162 | be32_to_cpu(r2->ir_startino)); | |
1da177e4 LT |
163 | break; |
164 | } | |
165 | default: | |
166 | ASSERT(0); | |
167 | } | |
168 | } | |
169 | #endif /* DEBUG */ | |
170 | ||
a23f6ef8 CH |
171 | int /* error (0 or EFSCORRUPTED) */ |
172 | xfs_btree_check_lblock( | |
173 | struct xfs_btree_cur *cur, /* btree cursor */ | |
174 | struct xfs_btree_lblock *block, /* btree long form block pointer */ | |
175 | int level, /* level of the btree block */ | |
176 | struct xfs_buf *bp) /* buffer for block, if any */ | |
177 | { | |
178 | int lblock_ok; /* block passes checks */ | |
179 | struct xfs_mount *mp; /* file system mount point */ | |
180 | ||
181 | mp = cur->bc_mp; | |
182 | lblock_ok = | |
183 | be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] && | |
184 | be16_to_cpu(block->bb_level) == level && | |
185 | be16_to_cpu(block->bb_numrecs) <= | |
ce5e42db | 186 | cur->bc_ops->get_maxrecs(cur, level) && |
a23f6ef8 CH |
187 | block->bb_leftsib && |
188 | (be64_to_cpu(block->bb_leftsib) == NULLDFSBNO || | |
189 | XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_leftsib))) && | |
190 | block->bb_rightsib && | |
191 | (be64_to_cpu(block->bb_rightsib) == NULLDFSBNO || | |
192 | XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_rightsib))); | |
193 | if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp, | |
194 | XFS_ERRTAG_BTREE_CHECK_LBLOCK, | |
195 | XFS_RANDOM_BTREE_CHECK_LBLOCK))) { | |
196 | if (bp) | |
197 | xfs_buftrace("LBTREE ERROR", bp); | |
198 | XFS_ERROR_REPORT("xfs_btree_check_lblock", XFS_ERRLEVEL_LOW, | |
199 | mp); | |
200 | return XFS_ERROR(EFSCORRUPTED); | |
201 | } | |
202 | return 0; | |
203 | } | |
204 | ||
1da177e4 LT |
205 | int /* error (0 or EFSCORRUPTED) */ |
206 | xfs_btree_check_sblock( | |
a23f6ef8 CH |
207 | struct xfs_btree_cur *cur, /* btree cursor */ |
208 | struct xfs_btree_sblock *block, /* btree short form block pointer */ | |
1da177e4 | 209 | int level, /* level of the btree block */ |
a23f6ef8 | 210 | struct xfs_buf *bp) /* buffer containing block */ |
1da177e4 | 211 | { |
a23f6ef8 CH |
212 | struct xfs_buf *agbp; /* buffer for ag. freespace struct */ |
213 | struct xfs_agf *agf; /* ag. freespace structure */ | |
1da177e4 LT |
214 | xfs_agblock_t agflen; /* native ag. freespace length */ |
215 | int sblock_ok; /* block passes checks */ | |
216 | ||
217 | agbp = cur->bc_private.a.agbp; | |
218 | agf = XFS_BUF_TO_AGF(agbp); | |
16259e7d | 219 | agflen = be32_to_cpu(agf->agf_length); |
1da177e4 | 220 | sblock_ok = |
16259e7d CH |
221 | be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] && |
222 | be16_to_cpu(block->bb_level) == level && | |
223 | be16_to_cpu(block->bb_numrecs) <= | |
ce5e42db | 224 | cur->bc_ops->get_maxrecs(cur, level) && |
16259e7d CH |
225 | (be32_to_cpu(block->bb_leftsib) == NULLAGBLOCK || |
226 | be32_to_cpu(block->bb_leftsib) < agflen) && | |
1da177e4 | 227 | block->bb_leftsib && |
16259e7d CH |
228 | (be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK || |
229 | be32_to_cpu(block->bb_rightsib) < agflen) && | |
1da177e4 LT |
230 | block->bb_rightsib; |
231 | if (unlikely(XFS_TEST_ERROR(!sblock_ok, cur->bc_mp, | |
232 | XFS_ERRTAG_BTREE_CHECK_SBLOCK, | |
233 | XFS_RANDOM_BTREE_CHECK_SBLOCK))) { | |
234 | if (bp) | |
235 | xfs_buftrace("SBTREE ERROR", bp); | |
236 | XFS_ERROR_REPORT("xfs_btree_check_sblock", XFS_ERRLEVEL_LOW, | |
237 | cur->bc_mp); | |
238 | return XFS_ERROR(EFSCORRUPTED); | |
239 | } | |
240 | return 0; | |
241 | } | |
242 | ||
243 | /* | |
a23f6ef8 CH |
244 | * Debug routine: check that block header is ok. |
245 | */ | |
246 | int | |
247 | xfs_btree_check_block( | |
248 | struct xfs_btree_cur *cur, /* btree cursor */ | |
249 | struct xfs_btree_block *block, /* generic btree block pointer */ | |
250 | int level, /* level of the btree block */ | |
251 | struct xfs_buf *bp) /* buffer containing block, if any */ | |
252 | { | |
253 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { | |
254 | return xfs_btree_check_lblock(cur, | |
255 | (struct xfs_btree_lblock *)block, level, bp); | |
256 | } else { | |
257 | return xfs_btree_check_sblock(cur, | |
258 | (struct xfs_btree_sblock *)block, level, bp); | |
259 | } | |
260 | } | |
261 | ||
262 | /* | |
263 | * Check that (long) pointer is ok. | |
264 | */ | |
265 | int /* error (0 or EFSCORRUPTED) */ | |
266 | xfs_btree_check_lptr( | |
267 | struct xfs_btree_cur *cur, /* btree cursor */ | |
268 | xfs_dfsbno_t bno, /* btree block disk address */ | |
269 | int level) /* btree block level */ | |
270 | { | |
271 | XFS_WANT_CORRUPTED_RETURN( | |
272 | level > 0 && | |
273 | bno != NULLDFSBNO && | |
274 | XFS_FSB_SANITY_CHECK(cur->bc_mp, bno)); | |
275 | return 0; | |
276 | } | |
277 | ||
278 | /* | |
279 | * Check that (short) pointer is ok. | |
1da177e4 LT |
280 | */ |
281 | int /* error (0 or EFSCORRUPTED) */ | |
282 | xfs_btree_check_sptr( | |
a23f6ef8 CH |
283 | struct xfs_btree_cur *cur, /* btree cursor */ |
284 | xfs_agblock_t bno, /* btree block disk address */ | |
285 | int level) /* btree block level */ | |
1da177e4 | 286 | { |
a23f6ef8 | 287 | xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks; |
1da177e4 | 288 | |
1da177e4 LT |
289 | XFS_WANT_CORRUPTED_RETURN( |
290 | level > 0 && | |
a23f6ef8 CH |
291 | bno != NULLAGBLOCK && |
292 | bno != 0 && | |
293 | bno < agblocks); | |
1da177e4 LT |
294 | return 0; |
295 | } | |
296 | ||
a23f6ef8 CH |
297 | /* |
298 | * Check that block ptr is ok. | |
299 | */ | |
300 | int /* error (0 or EFSCORRUPTED) */ | |
301 | xfs_btree_check_ptr( | |
302 | struct xfs_btree_cur *cur, /* btree cursor */ | |
303 | union xfs_btree_ptr *ptr, /* btree block disk address */ | |
304 | int index, /* offset from ptr to check */ | |
305 | int level) /* btree block level */ | |
306 | { | |
307 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { | |
308 | return xfs_btree_check_lptr(cur, | |
309 | be64_to_cpu((&ptr->l)[index]), level); | |
310 | } else { | |
311 | return xfs_btree_check_sptr(cur, | |
312 | be32_to_cpu((&ptr->s)[index]), level); | |
313 | } | |
314 | } | |
315 | ||
1da177e4 LT |
316 | /* |
317 | * Delete the btree cursor. | |
318 | */ | |
319 | void | |
320 | xfs_btree_del_cursor( | |
321 | xfs_btree_cur_t *cur, /* btree cursor */ | |
322 | int error) /* del because of error */ | |
323 | { | |
324 | int i; /* btree level */ | |
325 | ||
326 | /* | |
327 | * Clear the buffer pointers, and release the buffers. | |
328 | * If we're doing this in the face of an error, we | |
329 | * need to make sure to inspect all of the entries | |
330 | * in the bc_bufs array for buffers to be unlocked. | |
331 | * This is because some of the btree code works from | |
332 | * level n down to 0, and if we get an error along | |
333 | * the way we won't have initialized all the entries | |
334 | * down to 0. | |
335 | */ | |
336 | for (i = 0; i < cur->bc_nlevels; i++) { | |
337 | if (cur->bc_bufs[i]) | |
338 | xfs_btree_setbuf(cur, i, NULL); | |
339 | else if (!error) | |
340 | break; | |
341 | } | |
342 | /* | |
343 | * Can't free a bmap cursor without having dealt with the | |
344 | * allocated indirect blocks' accounting. | |
345 | */ | |
346 | ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP || | |
347 | cur->bc_private.b.allocated == 0); | |
348 | /* | |
349 | * Free the cursor. | |
350 | */ | |
351 | kmem_zone_free(xfs_btree_cur_zone, cur); | |
352 | } | |
353 | ||
354 | /* | |
355 | * Duplicate the btree cursor. | |
356 | * Allocate a new one, copy the record, re-get the buffers. | |
357 | */ | |
358 | int /* error */ | |
359 | xfs_btree_dup_cursor( | |
360 | xfs_btree_cur_t *cur, /* input cursor */ | |
361 | xfs_btree_cur_t **ncur) /* output cursor */ | |
362 | { | |
363 | xfs_buf_t *bp; /* btree block's buffer pointer */ | |
364 | int error; /* error return value */ | |
365 | int i; /* level number of btree block */ | |
366 | xfs_mount_t *mp; /* mount structure for filesystem */ | |
367 | xfs_btree_cur_t *new; /* new cursor value */ | |
368 | xfs_trans_t *tp; /* transaction pointer, can be NULL */ | |
369 | ||
370 | tp = cur->bc_tp; | |
371 | mp = cur->bc_mp; | |
561f7d17 | 372 | |
1da177e4 LT |
373 | /* |
374 | * Allocate a new cursor like the old one. | |
375 | */ | |
561f7d17 CH |
376 | new = cur->bc_ops->dup_cursor(cur); |
377 | ||
1da177e4 LT |
378 | /* |
379 | * Copy the record currently in the cursor. | |
380 | */ | |
381 | new->bc_rec = cur->bc_rec; | |
561f7d17 | 382 | |
1da177e4 LT |
383 | /* |
384 | * For each level current, re-get the buffer and copy the ptr value. | |
385 | */ | |
386 | for (i = 0; i < new->bc_nlevels; i++) { | |
387 | new->bc_ptrs[i] = cur->bc_ptrs[i]; | |
388 | new->bc_ra[i] = cur->bc_ra[i]; | |
389 | if ((bp = cur->bc_bufs[i])) { | |
390 | if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, | |
391 | XFS_BUF_ADDR(bp), mp->m_bsize, 0, &bp))) { | |
392 | xfs_btree_del_cursor(new, error); | |
393 | *ncur = NULL; | |
394 | return error; | |
395 | } | |
396 | new->bc_bufs[i] = bp; | |
397 | ASSERT(bp); | |
398 | ASSERT(!XFS_BUF_GETERROR(bp)); | |
399 | } else | |
400 | new->bc_bufs[i] = NULL; | |
401 | } | |
1da177e4 LT |
402 | *ncur = new; |
403 | return 0; | |
404 | } | |
405 | ||
65f1eaea CH |
406 | /* |
407 | * XFS btree block layout and addressing: | |
408 | * | |
409 | * There are two types of blocks in the btree: leaf and non-leaf blocks. | |
410 | * | |
411 | * The leaf record start with a header then followed by records containing | |
412 | * the values. A non-leaf block also starts with the same header, and | |
413 | * then first contains lookup keys followed by an equal number of pointers | |
414 | * to the btree blocks at the previous level. | |
415 | * | |
416 | * +--------+-------+-------+-------+-------+-------+-------+ | |
417 | * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N | | |
418 | * +--------+-------+-------+-------+-------+-------+-------+ | |
419 | * | |
420 | * +--------+-------+-------+-------+-------+-------+-------+ | |
421 | * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N | | |
422 | * +--------+-------+-------+-------+-------+-------+-------+ | |
423 | * | |
424 | * The header is called struct xfs_btree_block for reasons better left unknown | |
425 | * and comes in different versions for short (32bit) and long (64bit) block | |
426 | * pointers. The record and key structures are defined by the btree instances | |
427 | * and opaque to the btree core. The block pointers are simple disk endian | |
428 | * integers, available in a short (32bit) and long (64bit) variant. | |
429 | * | |
430 | * The helpers below calculate the offset of a given record, key or pointer | |
431 | * into a btree block (xfs_btree_*_offset) or return a pointer to the given | |
432 | * record, key or pointer (xfs_btree_*_addr). Note that all addressing | |
433 | * inside the btree block is done using indices starting at one, not zero! | |
434 | */ | |
435 | ||
436 | /* | |
437 | * Return size of the btree block header for this btree instance. | |
438 | */ | |
439 | static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur) | |
440 | { | |
441 | return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ? | |
442 | sizeof(struct xfs_btree_lblock) : | |
443 | sizeof(struct xfs_btree_sblock); | |
444 | } | |
445 | ||
446 | /* | |
447 | * Return size of btree block pointers for this btree instance. | |
448 | */ | |
449 | static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur) | |
450 | { | |
451 | return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ? | |
452 | sizeof(__be64) : sizeof(__be32); | |
453 | } | |
454 | ||
455 | /* | |
456 | * Calculate offset of the n-th record in a btree block. | |
457 | */ | |
458 | STATIC size_t | |
459 | xfs_btree_rec_offset( | |
460 | struct xfs_btree_cur *cur, | |
461 | int n) | |
462 | { | |
463 | return xfs_btree_block_len(cur) + | |
464 | (n - 1) * cur->bc_ops->rec_len; | |
465 | } | |
466 | ||
467 | /* | |
468 | * Calculate offset of the n-th key in a btree block. | |
469 | */ | |
470 | STATIC size_t | |
471 | xfs_btree_key_offset( | |
472 | struct xfs_btree_cur *cur, | |
473 | int n) | |
474 | { | |
475 | return xfs_btree_block_len(cur) + | |
476 | (n - 1) * cur->bc_ops->key_len; | |
477 | } | |
478 | ||
479 | /* | |
480 | * Calculate offset of the n-th block pointer in a btree block. | |
481 | */ | |
482 | STATIC size_t | |
483 | xfs_btree_ptr_offset( | |
484 | struct xfs_btree_cur *cur, | |
485 | int n, | |
486 | int level) | |
487 | { | |
488 | return xfs_btree_block_len(cur) + | |
489 | cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len + | |
490 | (n - 1) * xfs_btree_ptr_len(cur); | |
491 | } | |
492 | ||
493 | /* | |
494 | * Return a pointer to the n-th record in the btree block. | |
495 | */ | |
496 | STATIC union xfs_btree_rec * | |
497 | xfs_btree_rec_addr( | |
498 | struct xfs_btree_cur *cur, | |
499 | int n, | |
500 | struct xfs_btree_block *block) | |
501 | { | |
502 | return (union xfs_btree_rec *) | |
503 | ((char *)block + xfs_btree_rec_offset(cur, n)); | |
504 | } | |
505 | ||
506 | /* | |
507 | * Return a pointer to the n-th key in the btree block. | |
508 | */ | |
509 | STATIC union xfs_btree_key * | |
510 | xfs_btree_key_addr( | |
511 | struct xfs_btree_cur *cur, | |
512 | int n, | |
513 | struct xfs_btree_block *block) | |
514 | { | |
515 | return (union xfs_btree_key *) | |
516 | ((char *)block + xfs_btree_key_offset(cur, n)); | |
517 | } | |
518 | ||
519 | /* | |
520 | * Return a pointer to the n-th block pointer in the btree block. | |
521 | */ | |
522 | STATIC union xfs_btree_ptr * | |
523 | xfs_btree_ptr_addr( | |
524 | struct xfs_btree_cur *cur, | |
525 | int n, | |
526 | struct xfs_btree_block *block) | |
527 | { | |
528 | int level = xfs_btree_get_level(block); | |
529 | ||
530 | ASSERT(block->bb_level != 0); | |
531 | ||
532 | return (union xfs_btree_ptr *) | |
533 | ((char *)block + xfs_btree_ptr_offset(cur, n, level)); | |
534 | } | |
535 | ||
8186e517 CH |
536 | /* |
537 | * Get a the root block which is stored in the inode. | |
538 | * | |
539 | * For now this btree implementation assumes the btree root is always | |
540 | * stored in the if_broot field of an inode fork. | |
541 | */ | |
542 | STATIC struct xfs_btree_block * | |
543 | xfs_btree_get_iroot( | |
544 | struct xfs_btree_cur *cur) | |
545 | { | |
546 | struct xfs_ifork *ifp; | |
547 | ||
548 | ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork); | |
549 | return (struct xfs_btree_block *)ifp->if_broot; | |
550 | } | |
551 | ||
1da177e4 LT |
552 | /* |
553 | * Retrieve the block pointer from the cursor at the given level. | |
8186e517 | 554 | * This may be an inode btree root or from a buffer. |
1da177e4 | 555 | */ |
8186e517 | 556 | STATIC struct xfs_btree_block * /* generic btree block pointer */ |
1da177e4 | 557 | xfs_btree_get_block( |
8186e517 | 558 | struct xfs_btree_cur *cur, /* btree cursor */ |
1da177e4 | 559 | int level, /* level in btree */ |
8186e517 | 560 | struct xfs_buf **bpp) /* buffer containing the block */ |
1da177e4 | 561 | { |
8186e517 CH |
562 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
563 | (level == cur->bc_nlevels - 1)) { | |
564 | *bpp = NULL; | |
565 | return xfs_btree_get_iroot(cur); | |
1da177e4 | 566 | } |
8186e517 CH |
567 | |
568 | *bpp = cur->bc_bufs[level]; | |
569 | return XFS_BUF_TO_BLOCK(*bpp); | |
1da177e4 LT |
570 | } |
571 | ||
572 | /* | |
573 | * Get a buffer for the block, return it with no data read. | |
574 | * Long-form addressing. | |
575 | */ | |
576 | xfs_buf_t * /* buffer for fsbno */ | |
577 | xfs_btree_get_bufl( | |
578 | xfs_mount_t *mp, /* file system mount point */ | |
579 | xfs_trans_t *tp, /* transaction pointer */ | |
580 | xfs_fsblock_t fsbno, /* file system block number */ | |
581 | uint lock) /* lock flags for get_buf */ | |
582 | { | |
583 | xfs_buf_t *bp; /* buffer pointer (return value) */ | |
584 | xfs_daddr_t d; /* real disk block address */ | |
585 | ||
586 | ASSERT(fsbno != NULLFSBLOCK); | |
587 | d = XFS_FSB_TO_DADDR(mp, fsbno); | |
588 | bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock); | |
589 | ASSERT(bp); | |
590 | ASSERT(!XFS_BUF_GETERROR(bp)); | |
591 | return bp; | |
592 | } | |
593 | ||
594 | /* | |
595 | * Get a buffer for the block, return it with no data read. | |
596 | * Short-form addressing. | |
597 | */ | |
598 | xfs_buf_t * /* buffer for agno/agbno */ | |
599 | xfs_btree_get_bufs( | |
600 | xfs_mount_t *mp, /* file system mount point */ | |
601 | xfs_trans_t *tp, /* transaction pointer */ | |
602 | xfs_agnumber_t agno, /* allocation group number */ | |
603 | xfs_agblock_t agbno, /* allocation group block number */ | |
604 | uint lock) /* lock flags for get_buf */ | |
605 | { | |
606 | xfs_buf_t *bp; /* buffer pointer (return value) */ | |
607 | xfs_daddr_t d; /* real disk block address */ | |
608 | ||
609 | ASSERT(agno != NULLAGNUMBER); | |
610 | ASSERT(agbno != NULLAGBLOCK); | |
611 | d = XFS_AGB_TO_DADDR(mp, agno, agbno); | |
612 | bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock); | |
613 | ASSERT(bp); | |
614 | ASSERT(!XFS_BUF_GETERROR(bp)); | |
615 | return bp; | |
616 | } | |
617 | ||
1da177e4 LT |
618 | /* |
619 | * Check for the cursor referring to the last block at the given level. | |
620 | */ | |
621 | int /* 1=is last block, 0=not last block */ | |
622 | xfs_btree_islastblock( | |
623 | xfs_btree_cur_t *cur, /* btree cursor */ | |
624 | int level) /* level to check */ | |
625 | { | |
626 | xfs_btree_block_t *block; /* generic btree block pointer */ | |
627 | xfs_buf_t *bp; /* buffer containing block */ | |
628 | ||
629 | block = xfs_btree_get_block(cur, level, &bp); | |
630 | xfs_btree_check_block(cur, block, level, bp); | |
e99ab90d | 631 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
16259e7d | 632 | return be64_to_cpu(block->bb_u.l.bb_rightsib) == NULLDFSBNO; |
1da177e4 | 633 | else |
16259e7d | 634 | return be32_to_cpu(block->bb_u.s.bb_rightsib) == NULLAGBLOCK; |
1da177e4 LT |
635 | } |
636 | ||
cdcf4333 CH |
637 | /* |
638 | * Change the cursor to point to the first record at the given level. | |
639 | * Other levels are unaffected. | |
640 | */ | |
641 | int /* success=1, failure=0 */ | |
642 | xfs_btree_firstrec( | |
643 | xfs_btree_cur_t *cur, /* btree cursor */ | |
644 | int level) /* level to change */ | |
645 | { | |
646 | xfs_btree_block_t *block; /* generic btree block pointer */ | |
647 | xfs_buf_t *bp; /* buffer containing block */ | |
648 | ||
649 | /* | |
650 | * Get the block pointer for this level. | |
651 | */ | |
652 | block = xfs_btree_get_block(cur, level, &bp); | |
653 | xfs_btree_check_block(cur, block, level, bp); | |
654 | /* | |
655 | * It's empty, there is no such record. | |
656 | */ | |
f2277f06 | 657 | if (!block->bb_numrecs) |
cdcf4333 CH |
658 | return 0; |
659 | /* | |
660 | * Set the ptr value to 1, that's the first record/key. | |
661 | */ | |
662 | cur->bc_ptrs[level] = 1; | |
663 | return 1; | |
664 | } | |
665 | ||
1da177e4 LT |
666 | /* |
667 | * Change the cursor to point to the last record in the current block | |
668 | * at the given level. Other levels are unaffected. | |
669 | */ | |
670 | int /* success=1, failure=0 */ | |
671 | xfs_btree_lastrec( | |
672 | xfs_btree_cur_t *cur, /* btree cursor */ | |
673 | int level) /* level to change */ | |
674 | { | |
675 | xfs_btree_block_t *block; /* generic btree block pointer */ | |
676 | xfs_buf_t *bp; /* buffer containing block */ | |
677 | ||
678 | /* | |
679 | * Get the block pointer for this level. | |
680 | */ | |
681 | block = xfs_btree_get_block(cur, level, &bp); | |
682 | xfs_btree_check_block(cur, block, level, bp); | |
683 | /* | |
684 | * It's empty, there is no such record. | |
685 | */ | |
f2277f06 | 686 | if (!block->bb_numrecs) |
1da177e4 LT |
687 | return 0; |
688 | /* | |
689 | * Set the ptr value to numrecs, that's the last record/key. | |
690 | */ | |
f2277f06 | 691 | cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs); |
1da177e4 LT |
692 | return 1; |
693 | } | |
694 | ||
695 | /* | |
696 | * Compute first and last byte offsets for the fields given. | |
697 | * Interprets the offsets table, which contains struct field offsets. | |
698 | */ | |
699 | void | |
700 | xfs_btree_offsets( | |
701 | __int64_t fields, /* bitmask of fields */ | |
702 | const short *offsets, /* table of field offsets */ | |
703 | int nbits, /* number of bits to inspect */ | |
704 | int *first, /* output: first byte offset */ | |
705 | int *last) /* output: last byte offset */ | |
706 | { | |
707 | int i; /* current bit number */ | |
708 | __int64_t imask; /* mask for current bit number */ | |
709 | ||
710 | ASSERT(fields != 0); | |
711 | /* | |
712 | * Find the lowest bit, so the first byte offset. | |
713 | */ | |
714 | for (i = 0, imask = 1LL; ; i++, imask <<= 1) { | |
715 | if (imask & fields) { | |
716 | *first = offsets[i]; | |
717 | break; | |
718 | } | |
719 | } | |
720 | /* | |
721 | * Find the highest bit, so the last byte offset. | |
722 | */ | |
723 | for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) { | |
724 | if (imask & fields) { | |
725 | *last = offsets[i + 1] - 1; | |
726 | break; | |
727 | } | |
728 | } | |
729 | } | |
730 | ||
731 | /* | |
732 | * Get a buffer for the block, return it read in. | |
733 | * Long-form addressing. | |
734 | */ | |
735 | int /* error */ | |
736 | xfs_btree_read_bufl( | |
737 | xfs_mount_t *mp, /* file system mount point */ | |
738 | xfs_trans_t *tp, /* transaction pointer */ | |
739 | xfs_fsblock_t fsbno, /* file system block number */ | |
740 | uint lock, /* lock flags for read_buf */ | |
741 | xfs_buf_t **bpp, /* buffer for fsbno */ | |
742 | int refval) /* ref count value for buffer */ | |
743 | { | |
744 | xfs_buf_t *bp; /* return value */ | |
745 | xfs_daddr_t d; /* real disk block address */ | |
746 | int error; | |
747 | ||
748 | ASSERT(fsbno != NULLFSBLOCK); | |
749 | d = XFS_FSB_TO_DADDR(mp, fsbno); | |
750 | if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d, | |
751 | mp->m_bsize, lock, &bp))) { | |
752 | return error; | |
753 | } | |
754 | ASSERT(!bp || !XFS_BUF_GETERROR(bp)); | |
755 | if (bp != NULL) { | |
756 | XFS_BUF_SET_VTYPE_REF(bp, B_FS_MAP, refval); | |
757 | } | |
758 | *bpp = bp; | |
759 | return 0; | |
760 | } | |
761 | ||
762 | /* | |
763 | * Get a buffer for the block, return it read in. | |
764 | * Short-form addressing. | |
765 | */ | |
766 | int /* error */ | |
767 | xfs_btree_read_bufs( | |
768 | xfs_mount_t *mp, /* file system mount point */ | |
769 | xfs_trans_t *tp, /* transaction pointer */ | |
770 | xfs_agnumber_t agno, /* allocation group number */ | |
771 | xfs_agblock_t agbno, /* allocation group block number */ | |
772 | uint lock, /* lock flags for read_buf */ | |
773 | xfs_buf_t **bpp, /* buffer for agno/agbno */ | |
774 | int refval) /* ref count value for buffer */ | |
775 | { | |
776 | xfs_buf_t *bp; /* return value */ | |
777 | xfs_daddr_t d; /* real disk block address */ | |
778 | int error; | |
779 | ||
780 | ASSERT(agno != NULLAGNUMBER); | |
781 | ASSERT(agbno != NULLAGBLOCK); | |
782 | d = XFS_AGB_TO_DADDR(mp, agno, agbno); | |
783 | if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d, | |
784 | mp->m_bsize, lock, &bp))) { | |
785 | return error; | |
786 | } | |
787 | ASSERT(!bp || !XFS_BUF_GETERROR(bp)); | |
788 | if (bp != NULL) { | |
789 | switch (refval) { | |
790 | case XFS_ALLOC_BTREE_REF: | |
791 | XFS_BUF_SET_VTYPE_REF(bp, B_FS_MAP, refval); | |
792 | break; | |
793 | case XFS_INO_BTREE_REF: | |
794 | XFS_BUF_SET_VTYPE_REF(bp, B_FS_INOMAP, refval); | |
795 | break; | |
796 | } | |
797 | } | |
798 | *bpp = bp; | |
799 | return 0; | |
800 | } | |
801 | ||
802 | /* | |
803 | * Read-ahead the block, don't wait for it, don't return a buffer. | |
804 | * Long-form addressing. | |
805 | */ | |
806 | /* ARGSUSED */ | |
807 | void | |
808 | xfs_btree_reada_bufl( | |
809 | xfs_mount_t *mp, /* file system mount point */ | |
810 | xfs_fsblock_t fsbno, /* file system block number */ | |
811 | xfs_extlen_t count) /* count of filesystem blocks */ | |
812 | { | |
813 | xfs_daddr_t d; | |
814 | ||
815 | ASSERT(fsbno != NULLFSBLOCK); | |
816 | d = XFS_FSB_TO_DADDR(mp, fsbno); | |
817 | xfs_baread(mp->m_ddev_targp, d, mp->m_bsize * count); | |
818 | } | |
819 | ||
820 | /* | |
821 | * Read-ahead the block, don't wait for it, don't return a buffer. | |
822 | * Short-form addressing. | |
823 | */ | |
824 | /* ARGSUSED */ | |
825 | void | |
826 | xfs_btree_reada_bufs( | |
827 | xfs_mount_t *mp, /* file system mount point */ | |
828 | xfs_agnumber_t agno, /* allocation group number */ | |
829 | xfs_agblock_t agbno, /* allocation group block number */ | |
830 | xfs_extlen_t count) /* count of filesystem blocks */ | |
831 | { | |
832 | xfs_daddr_t d; | |
833 | ||
834 | ASSERT(agno != NULLAGNUMBER); | |
835 | ASSERT(agbno != NULLAGBLOCK); | |
836 | d = XFS_AGB_TO_DADDR(mp, agno, agbno); | |
837 | xfs_baread(mp->m_ddev_targp, d, mp->m_bsize * count); | |
838 | } | |
839 | ||
b524bfee CH |
840 | STATIC int |
841 | xfs_btree_readahead_lblock( | |
842 | struct xfs_btree_cur *cur, | |
843 | int lr, | |
844 | struct xfs_btree_block *block) | |
845 | { | |
846 | int rval = 0; | |
847 | xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib); | |
848 | xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib); | |
849 | ||
850 | if ((lr & XFS_BTCUR_LEFTRA) && left != NULLDFSBNO) { | |
851 | xfs_btree_reada_bufl(cur->bc_mp, left, 1); | |
852 | rval++; | |
853 | } | |
854 | ||
855 | if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLDFSBNO) { | |
856 | xfs_btree_reada_bufl(cur->bc_mp, right, 1); | |
857 | rval++; | |
858 | } | |
859 | ||
860 | return rval; | |
861 | } | |
862 | ||
863 | STATIC int | |
864 | xfs_btree_readahead_sblock( | |
865 | struct xfs_btree_cur *cur, | |
866 | int lr, | |
867 | struct xfs_btree_block *block) | |
868 | { | |
869 | int rval = 0; | |
870 | xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib); | |
871 | xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib); | |
872 | ||
873 | ||
874 | if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) { | |
875 | xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno, | |
876 | left, 1); | |
877 | rval++; | |
878 | } | |
879 | ||
880 | if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) { | |
881 | xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno, | |
882 | right, 1); | |
883 | rval++; | |
884 | } | |
885 | ||
886 | return rval; | |
887 | } | |
888 | ||
1da177e4 LT |
889 | /* |
890 | * Read-ahead btree blocks, at the given level. | |
891 | * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA. | |
892 | */ | |
893 | int | |
b524bfee CH |
894 | xfs_btree_readahead( |
895 | struct xfs_btree_cur *cur, /* btree cursor */ | |
1da177e4 LT |
896 | int lev, /* level in btree */ |
897 | int lr) /* left/right bits */ | |
898 | { | |
b524bfee CH |
899 | struct xfs_btree_block *block; |
900 | ||
901 | /* | |
902 | * No readahead needed if we are at the root level and the | |
903 | * btree root is stored in the inode. | |
904 | */ | |
905 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && | |
906 | (lev == cur->bc_nlevels - 1)) | |
907 | return 0; | |
908 | ||
909 | if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev]) | |
910 | return 0; | |
1da177e4 | 911 | |
1da177e4 | 912 | cur->bc_ra[lev] |= lr; |
b524bfee CH |
913 | block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]); |
914 | ||
915 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) | |
916 | return xfs_btree_readahead_lblock(cur, lr, block); | |
917 | return xfs_btree_readahead_sblock(cur, lr, block); | |
1da177e4 LT |
918 | } |
919 | ||
920 | /* | |
921 | * Set the buffer for level "lev" in the cursor to bp, releasing | |
922 | * any previous buffer. | |
923 | */ | |
924 | void | |
925 | xfs_btree_setbuf( | |
926 | xfs_btree_cur_t *cur, /* btree cursor */ | |
927 | int lev, /* level in btree */ | |
928 | xfs_buf_t *bp) /* new buffer to set */ | |
929 | { | |
930 | xfs_btree_block_t *b; /* btree block */ | |
931 | xfs_buf_t *obp; /* old buffer pointer */ | |
932 | ||
933 | obp = cur->bc_bufs[lev]; | |
934 | if (obp) | |
935 | xfs_trans_brelse(cur->bc_tp, obp); | |
936 | cur->bc_bufs[lev] = bp; | |
937 | cur->bc_ra[lev] = 0; | |
938 | if (!bp) | |
939 | return; | |
940 | b = XFS_BUF_TO_BLOCK(bp); | |
e99ab90d | 941 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
16259e7d | 942 | if (be64_to_cpu(b->bb_u.l.bb_leftsib) == NULLDFSBNO) |
1da177e4 | 943 | cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA; |
16259e7d | 944 | if (be64_to_cpu(b->bb_u.l.bb_rightsib) == NULLDFSBNO) |
1da177e4 LT |
945 | cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA; |
946 | } else { | |
16259e7d | 947 | if (be32_to_cpu(b->bb_u.s.bb_leftsib) == NULLAGBLOCK) |
1da177e4 | 948 | cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA; |
16259e7d | 949 | if (be32_to_cpu(b->bb_u.s.bb_rightsib) == NULLAGBLOCK) |
1da177e4 LT |
950 | cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA; |
951 | } | |
952 | } | |
637aa50f CH |
953 | |
954 | STATIC int | |
955 | xfs_btree_ptr_is_null( | |
956 | struct xfs_btree_cur *cur, | |
957 | union xfs_btree_ptr *ptr) | |
958 | { | |
959 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) | |
960 | return be64_to_cpu(ptr->l) == NULLFSBLOCK; | |
961 | else | |
962 | return be32_to_cpu(ptr->s) == NULLAGBLOCK; | |
963 | } | |
964 | ||
965 | /* | |
966 | * Get/set/init sibling pointers | |
967 | */ | |
968 | STATIC void | |
969 | xfs_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 | ||
990 | STATIC xfs_daddr_t | |
991 | xfs_btree_ptr_to_daddr( | |
992 | struct xfs_btree_cur *cur, | |
993 | union xfs_btree_ptr *ptr) | |
994 | { | |
995 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { | |
996 | ASSERT(be64_to_cpu(ptr->l) != NULLFSBLOCK); | |
997 | ||
998 | return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l)); | |
999 | } else { | |
1000 | ASSERT(cur->bc_private.a.agno != NULLAGNUMBER); | |
1001 | ASSERT(be32_to_cpu(ptr->s) != NULLAGBLOCK); | |
1002 | ||
1003 | return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno, | |
1004 | be32_to_cpu(ptr->s)); | |
1005 | } | |
1006 | } | |
1007 | ||
1008 | STATIC void | |
1009 | xfs_btree_set_refs( | |
1010 | struct xfs_btree_cur *cur, | |
1011 | struct xfs_buf *bp) | |
1012 | { | |
1013 | switch (cur->bc_btnum) { | |
1014 | case XFS_BTNUM_BNO: | |
1015 | case XFS_BTNUM_CNT: | |
1016 | XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_ALLOC_BTREE_REF); | |
1017 | break; | |
1018 | case XFS_BTNUM_INO: | |
1019 | XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_INOMAP, XFS_INO_BTREE_REF); | |
1020 | break; | |
1021 | case XFS_BTNUM_BMAP: | |
1022 | XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_BMAP_BTREE_REF); | |
1023 | break; | |
1024 | default: | |
1025 | ASSERT(0); | |
1026 | } | |
1027 | } | |
1028 | ||
1029 | /* | |
1030 | * Read in the buffer at the given ptr and return the buffer and | |
1031 | * the block pointer within the buffer. | |
1032 | */ | |
1033 | STATIC int | |
1034 | xfs_btree_read_buf_block( | |
1035 | struct xfs_btree_cur *cur, | |
1036 | union xfs_btree_ptr *ptr, | |
1037 | int level, | |
1038 | int flags, | |
1039 | struct xfs_btree_block **block, | |
1040 | struct xfs_buf **bpp) | |
1041 | { | |
1042 | struct xfs_mount *mp = cur->bc_mp; | |
1043 | xfs_daddr_t d; | |
1044 | int error; | |
1045 | ||
1046 | /* need to sort out how callers deal with failures first */ | |
1047 | ASSERT(!(flags & XFS_BUF_TRYLOCK)); | |
1048 | ||
1049 | d = xfs_btree_ptr_to_daddr(cur, ptr); | |
1050 | error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d, | |
1051 | mp->m_bsize, flags, bpp); | |
1052 | if (error) | |
1053 | return error; | |
1054 | ||
1055 | ASSERT(*bpp != NULL); | |
1056 | ASSERT(!XFS_BUF_GETERROR(*bpp)); | |
1057 | ||
1058 | xfs_btree_set_refs(cur, *bpp); | |
1059 | *block = XFS_BUF_TO_BLOCK(*bpp); | |
1060 | ||
1061 | error = xfs_btree_check_block(cur, *block, level, *bpp); | |
1062 | if (error) | |
1063 | xfs_trans_brelse(cur->bc_tp, *bpp); | |
1064 | return error; | |
1065 | } | |
1066 | ||
1067 | /* | |
1068 | * Increment cursor by one record at the level. | |
1069 | * For nonzero levels the leaf-ward information is untouched. | |
1070 | */ | |
1071 | int /* error */ | |
1072 | xfs_btree_increment( | |
1073 | struct xfs_btree_cur *cur, | |
1074 | int level, | |
1075 | int *stat) /* success/failure */ | |
1076 | { | |
1077 | struct xfs_btree_block *block; | |
1078 | union xfs_btree_ptr ptr; | |
1079 | struct xfs_buf *bp; | |
1080 | int error; /* error return value */ | |
1081 | int lev; | |
1082 | ||
1083 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); | |
1084 | XFS_BTREE_TRACE_ARGI(cur, level); | |
1085 | ||
1086 | ASSERT(level < cur->bc_nlevels); | |
1087 | ||
1088 | /* Read-ahead to the right at this level. */ | |
1089 | xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA); | |
1090 | ||
1091 | /* Get a pointer to the btree block. */ | |
1092 | block = xfs_btree_get_block(cur, level, &bp); | |
1093 | ||
1094 | #ifdef DEBUG | |
1095 | error = xfs_btree_check_block(cur, block, level, bp); | |
1096 | if (error) | |
1097 | goto error0; | |
1098 | #endif | |
1099 | ||
1100 | /* We're done if we remain in the block after the increment. */ | |
1101 | if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block)) | |
1102 | goto out1; | |
1103 | ||
1104 | /* Fail if we just went off the right edge of the tree. */ | |
1105 | xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); | |
1106 | if (xfs_btree_ptr_is_null(cur, &ptr)) | |
1107 | goto out0; | |
1108 | ||
1109 | XFS_BTREE_STATS_INC(cur, increment); | |
1110 | ||
1111 | /* | |
1112 | * March up the tree incrementing pointers. | |
1113 | * Stop when we don't go off the right edge of a block. | |
1114 | */ | |
1115 | for (lev = level + 1; lev < cur->bc_nlevels; lev++) { | |
1116 | block = xfs_btree_get_block(cur, lev, &bp); | |
1117 | ||
1118 | #ifdef DEBUG | |
1119 | error = xfs_btree_check_block(cur, block, lev, bp); | |
1120 | if (error) | |
1121 | goto error0; | |
1122 | #endif | |
1123 | ||
1124 | if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block)) | |
1125 | break; | |
1126 | ||
1127 | /* Read-ahead the right block for the next loop. */ | |
1128 | xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA); | |
1129 | } | |
1130 | ||
1131 | /* | |
1132 | * If we went off the root then we are either seriously | |
1133 | * confused or have the tree root in an inode. | |
1134 | */ | |
1135 | if (lev == cur->bc_nlevels) { | |
1136 | if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) | |
1137 | goto out0; | |
1138 | ASSERT(0); | |
1139 | error = EFSCORRUPTED; | |
1140 | goto error0; | |
1141 | } | |
1142 | ASSERT(lev < cur->bc_nlevels); | |
1143 | ||
1144 | /* | |
1145 | * Now walk back down the tree, fixing up the cursor's buffer | |
1146 | * pointers and key numbers. | |
1147 | */ | |
1148 | for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) { | |
1149 | union xfs_btree_ptr *ptrp; | |
1150 | ||
1151 | ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block); | |
1152 | error = xfs_btree_read_buf_block(cur, ptrp, --lev, | |
1153 | 0, &block, &bp); | |
1154 | if (error) | |
1155 | goto error0; | |
1156 | ||
1157 | xfs_btree_setbuf(cur, lev, bp); | |
1158 | cur->bc_ptrs[lev] = 1; | |
1159 | } | |
1160 | out1: | |
1161 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); | |
1162 | *stat = 1; | |
1163 | return 0; | |
1164 | ||
1165 | out0: | |
1166 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); | |
1167 | *stat = 0; | |
1168 | return 0; | |
1169 | ||
1170 | error0: | |
1171 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); | |
1172 | return error; | |
1173 | } |