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Merge branches 'ib-mfd-base-acpi-dma-4.3', 'ib-mfd-clocksource-rtc-watchdog-4.3'...
[deliverable/linux.git] / fs / nilfs2 / btree.c
1 /*
2 * btree.c - NILFS B-tree.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Koji Sato <koji@osrg.net>.
21 */
22
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/errno.h>
26 #include <linux/pagevec.h>
27 #include "nilfs.h"
28 #include "page.h"
29 #include "btnode.h"
30 #include "btree.h"
31 #include "alloc.h"
32 #include "dat.h"
33
34 static void __nilfs_btree_init(struct nilfs_bmap *bmap);
35
36 static struct nilfs_btree_path *nilfs_btree_alloc_path(void)
37 {
38 struct nilfs_btree_path *path;
39 int level = NILFS_BTREE_LEVEL_DATA;
40
41 path = kmem_cache_alloc(nilfs_btree_path_cache, GFP_NOFS);
42 if (path == NULL)
43 goto out;
44
45 for (; level < NILFS_BTREE_LEVEL_MAX; level++) {
46 path[level].bp_bh = NULL;
47 path[level].bp_sib_bh = NULL;
48 path[level].bp_index = 0;
49 path[level].bp_oldreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
50 path[level].bp_newreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
51 path[level].bp_op = NULL;
52 }
53
54 out:
55 return path;
56 }
57
58 static void nilfs_btree_free_path(struct nilfs_btree_path *path)
59 {
60 int level = NILFS_BTREE_LEVEL_DATA;
61
62 for (; level < NILFS_BTREE_LEVEL_MAX; level++)
63 brelse(path[level].bp_bh);
64
65 kmem_cache_free(nilfs_btree_path_cache, path);
66 }
67
68 /*
69 * B-tree node operations
70 */
71 static int nilfs_btree_get_new_block(const struct nilfs_bmap *btree,
72 __u64 ptr, struct buffer_head **bhp)
73 {
74 struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
75 struct buffer_head *bh;
76
77 bh = nilfs_btnode_create_block(btnc, ptr);
78 if (!bh)
79 return -ENOMEM;
80
81 set_buffer_nilfs_volatile(bh);
82 *bhp = bh;
83 return 0;
84 }
85
86 static int nilfs_btree_node_get_flags(const struct nilfs_btree_node *node)
87 {
88 return node->bn_flags;
89 }
90
91 static void
92 nilfs_btree_node_set_flags(struct nilfs_btree_node *node, int flags)
93 {
94 node->bn_flags = flags;
95 }
96
97 static int nilfs_btree_node_root(const struct nilfs_btree_node *node)
98 {
99 return nilfs_btree_node_get_flags(node) & NILFS_BTREE_NODE_ROOT;
100 }
101
102 static int nilfs_btree_node_get_level(const struct nilfs_btree_node *node)
103 {
104 return node->bn_level;
105 }
106
107 static void
108 nilfs_btree_node_set_level(struct nilfs_btree_node *node, int level)
109 {
110 node->bn_level = level;
111 }
112
113 static int nilfs_btree_node_get_nchildren(const struct nilfs_btree_node *node)
114 {
115 return le16_to_cpu(node->bn_nchildren);
116 }
117
118 static void
119 nilfs_btree_node_set_nchildren(struct nilfs_btree_node *node, int nchildren)
120 {
121 node->bn_nchildren = cpu_to_le16(nchildren);
122 }
123
124 static int nilfs_btree_node_size(const struct nilfs_bmap *btree)
125 {
126 return 1 << btree->b_inode->i_blkbits;
127 }
128
129 static int nilfs_btree_nchildren_per_block(const struct nilfs_bmap *btree)
130 {
131 return btree->b_nchildren_per_block;
132 }
133
134 static __le64 *
135 nilfs_btree_node_dkeys(const struct nilfs_btree_node *node)
136 {
137 return (__le64 *)((char *)(node + 1) +
138 (nilfs_btree_node_root(node) ?
139 0 : NILFS_BTREE_NODE_EXTRA_PAD_SIZE));
140 }
141
142 static __le64 *
143 nilfs_btree_node_dptrs(const struct nilfs_btree_node *node, int ncmax)
144 {
145 return (__le64 *)(nilfs_btree_node_dkeys(node) + ncmax);
146 }
147
148 static __u64
149 nilfs_btree_node_get_key(const struct nilfs_btree_node *node, int index)
150 {
151 return le64_to_cpu(*(nilfs_btree_node_dkeys(node) + index));
152 }
153
154 static void
155 nilfs_btree_node_set_key(struct nilfs_btree_node *node, int index, __u64 key)
156 {
157 *(nilfs_btree_node_dkeys(node) + index) = cpu_to_le64(key);
158 }
159
160 static __u64
161 nilfs_btree_node_get_ptr(const struct nilfs_btree_node *node, int index,
162 int ncmax)
163 {
164 return le64_to_cpu(*(nilfs_btree_node_dptrs(node, ncmax) + index));
165 }
166
167 static void
168 nilfs_btree_node_set_ptr(struct nilfs_btree_node *node, int index, __u64 ptr,
169 int ncmax)
170 {
171 *(nilfs_btree_node_dptrs(node, ncmax) + index) = cpu_to_le64(ptr);
172 }
173
174 static void nilfs_btree_node_init(struct nilfs_btree_node *node, int flags,
175 int level, int nchildren, int ncmax,
176 const __u64 *keys, const __u64 *ptrs)
177 {
178 __le64 *dkeys;
179 __le64 *dptrs;
180 int i;
181
182 nilfs_btree_node_set_flags(node, flags);
183 nilfs_btree_node_set_level(node, level);
184 nilfs_btree_node_set_nchildren(node, nchildren);
185
186 dkeys = nilfs_btree_node_dkeys(node);
187 dptrs = nilfs_btree_node_dptrs(node, ncmax);
188 for (i = 0; i < nchildren; i++) {
189 dkeys[i] = cpu_to_le64(keys[i]);
190 dptrs[i] = cpu_to_le64(ptrs[i]);
191 }
192 }
193
194 /* Assume the buffer heads corresponding to left and right are locked. */
195 static void nilfs_btree_node_move_left(struct nilfs_btree_node *left,
196 struct nilfs_btree_node *right,
197 int n, int lncmax, int rncmax)
198 {
199 __le64 *ldkeys, *rdkeys;
200 __le64 *ldptrs, *rdptrs;
201 int lnchildren, rnchildren;
202
203 ldkeys = nilfs_btree_node_dkeys(left);
204 ldptrs = nilfs_btree_node_dptrs(left, lncmax);
205 lnchildren = nilfs_btree_node_get_nchildren(left);
206
207 rdkeys = nilfs_btree_node_dkeys(right);
208 rdptrs = nilfs_btree_node_dptrs(right, rncmax);
209 rnchildren = nilfs_btree_node_get_nchildren(right);
210
211 memcpy(ldkeys + lnchildren, rdkeys, n * sizeof(*rdkeys));
212 memcpy(ldptrs + lnchildren, rdptrs, n * sizeof(*rdptrs));
213 memmove(rdkeys, rdkeys + n, (rnchildren - n) * sizeof(*rdkeys));
214 memmove(rdptrs, rdptrs + n, (rnchildren - n) * sizeof(*rdptrs));
215
216 lnchildren += n;
217 rnchildren -= n;
218 nilfs_btree_node_set_nchildren(left, lnchildren);
219 nilfs_btree_node_set_nchildren(right, rnchildren);
220 }
221
222 /* Assume that the buffer heads corresponding to left and right are locked. */
223 static void nilfs_btree_node_move_right(struct nilfs_btree_node *left,
224 struct nilfs_btree_node *right,
225 int n, int lncmax, int rncmax)
226 {
227 __le64 *ldkeys, *rdkeys;
228 __le64 *ldptrs, *rdptrs;
229 int lnchildren, rnchildren;
230
231 ldkeys = nilfs_btree_node_dkeys(left);
232 ldptrs = nilfs_btree_node_dptrs(left, lncmax);
233 lnchildren = nilfs_btree_node_get_nchildren(left);
234
235 rdkeys = nilfs_btree_node_dkeys(right);
236 rdptrs = nilfs_btree_node_dptrs(right, rncmax);
237 rnchildren = nilfs_btree_node_get_nchildren(right);
238
239 memmove(rdkeys + n, rdkeys, rnchildren * sizeof(*rdkeys));
240 memmove(rdptrs + n, rdptrs, rnchildren * sizeof(*rdptrs));
241 memcpy(rdkeys, ldkeys + lnchildren - n, n * sizeof(*rdkeys));
242 memcpy(rdptrs, ldptrs + lnchildren - n, n * sizeof(*rdptrs));
243
244 lnchildren -= n;
245 rnchildren += n;
246 nilfs_btree_node_set_nchildren(left, lnchildren);
247 nilfs_btree_node_set_nchildren(right, rnchildren);
248 }
249
250 /* Assume that the buffer head corresponding to node is locked. */
251 static void nilfs_btree_node_insert(struct nilfs_btree_node *node, int index,
252 __u64 key, __u64 ptr, int ncmax)
253 {
254 __le64 *dkeys;
255 __le64 *dptrs;
256 int nchildren;
257
258 dkeys = nilfs_btree_node_dkeys(node);
259 dptrs = nilfs_btree_node_dptrs(node, ncmax);
260 nchildren = nilfs_btree_node_get_nchildren(node);
261 if (index < nchildren) {
262 memmove(dkeys + index + 1, dkeys + index,
263 (nchildren - index) * sizeof(*dkeys));
264 memmove(dptrs + index + 1, dptrs + index,
265 (nchildren - index) * sizeof(*dptrs));
266 }
267 dkeys[index] = cpu_to_le64(key);
268 dptrs[index] = cpu_to_le64(ptr);
269 nchildren++;
270 nilfs_btree_node_set_nchildren(node, nchildren);
271 }
272
273 /* Assume that the buffer head corresponding to node is locked. */
274 static void nilfs_btree_node_delete(struct nilfs_btree_node *node, int index,
275 __u64 *keyp, __u64 *ptrp, int ncmax)
276 {
277 __u64 key;
278 __u64 ptr;
279 __le64 *dkeys;
280 __le64 *dptrs;
281 int nchildren;
282
283 dkeys = nilfs_btree_node_dkeys(node);
284 dptrs = nilfs_btree_node_dptrs(node, ncmax);
285 key = le64_to_cpu(dkeys[index]);
286 ptr = le64_to_cpu(dptrs[index]);
287 nchildren = nilfs_btree_node_get_nchildren(node);
288 if (keyp != NULL)
289 *keyp = key;
290 if (ptrp != NULL)
291 *ptrp = ptr;
292
293 if (index < nchildren - 1) {
294 memmove(dkeys + index, dkeys + index + 1,
295 (nchildren - index - 1) * sizeof(*dkeys));
296 memmove(dptrs + index, dptrs + index + 1,
297 (nchildren - index - 1) * sizeof(*dptrs));
298 }
299 nchildren--;
300 nilfs_btree_node_set_nchildren(node, nchildren);
301 }
302
303 static int nilfs_btree_node_lookup(const struct nilfs_btree_node *node,
304 __u64 key, int *indexp)
305 {
306 __u64 nkey;
307 int index, low, high, s;
308
309 /* binary search */
310 low = 0;
311 high = nilfs_btree_node_get_nchildren(node) - 1;
312 index = 0;
313 s = 0;
314 while (low <= high) {
315 index = (low + high) / 2;
316 nkey = nilfs_btree_node_get_key(node, index);
317 if (nkey == key) {
318 s = 0;
319 goto out;
320 } else if (nkey < key) {
321 low = index + 1;
322 s = -1;
323 } else {
324 high = index - 1;
325 s = 1;
326 }
327 }
328
329 /* adjust index */
330 if (nilfs_btree_node_get_level(node) > NILFS_BTREE_LEVEL_NODE_MIN) {
331 if (s > 0 && index > 0)
332 index--;
333 } else if (s < 0)
334 index++;
335
336 out:
337 *indexp = index;
338
339 return s == 0;
340 }
341
342 /**
343 * nilfs_btree_node_broken - verify consistency of btree node
344 * @node: btree node block to be examined
345 * @size: node size (in bytes)
346 * @blocknr: block number
347 *
348 * Return Value: If node is broken, 1 is returned. Otherwise, 0 is returned.
349 */
350 static int nilfs_btree_node_broken(const struct nilfs_btree_node *node,
351 size_t size, sector_t blocknr)
352 {
353 int level, flags, nchildren;
354 int ret = 0;
355
356 level = nilfs_btree_node_get_level(node);
357 flags = nilfs_btree_node_get_flags(node);
358 nchildren = nilfs_btree_node_get_nchildren(node);
359
360 if (unlikely(level < NILFS_BTREE_LEVEL_NODE_MIN ||
361 level >= NILFS_BTREE_LEVEL_MAX ||
362 (flags & NILFS_BTREE_NODE_ROOT) ||
363 nchildren < 0 ||
364 nchildren > NILFS_BTREE_NODE_NCHILDREN_MAX(size))) {
365 printk(KERN_CRIT "NILFS: bad btree node (blocknr=%llu): "
366 "level = %d, flags = 0x%x, nchildren = %d\n",
367 (unsigned long long)blocknr, level, flags, nchildren);
368 ret = 1;
369 }
370 return ret;
371 }
372
373 /**
374 * nilfs_btree_root_broken - verify consistency of btree root node
375 * @node: btree root node to be examined
376 * @ino: inode number
377 *
378 * Return Value: If node is broken, 1 is returned. Otherwise, 0 is returned.
379 */
380 static int nilfs_btree_root_broken(const struct nilfs_btree_node *node,
381 unsigned long ino)
382 {
383 int level, flags, nchildren;
384 int ret = 0;
385
386 level = nilfs_btree_node_get_level(node);
387 flags = nilfs_btree_node_get_flags(node);
388 nchildren = nilfs_btree_node_get_nchildren(node);
389
390 if (unlikely(level < NILFS_BTREE_LEVEL_NODE_MIN ||
391 level >= NILFS_BTREE_LEVEL_MAX ||
392 nchildren < 0 ||
393 nchildren > NILFS_BTREE_ROOT_NCHILDREN_MAX)) {
394 pr_crit("NILFS: bad btree root (inode number=%lu): level = %d, flags = 0x%x, nchildren = %d\n",
395 ino, level, flags, nchildren);
396 ret = 1;
397 }
398 return ret;
399 }
400
401 int nilfs_btree_broken_node_block(struct buffer_head *bh)
402 {
403 int ret;
404
405 if (buffer_nilfs_checked(bh))
406 return 0;
407
408 ret = nilfs_btree_node_broken((struct nilfs_btree_node *)bh->b_data,
409 bh->b_size, bh->b_blocknr);
410 if (likely(!ret))
411 set_buffer_nilfs_checked(bh);
412 return ret;
413 }
414
415 static struct nilfs_btree_node *
416 nilfs_btree_get_root(const struct nilfs_bmap *btree)
417 {
418 return (struct nilfs_btree_node *)btree->b_u.u_data;
419 }
420
421 static struct nilfs_btree_node *
422 nilfs_btree_get_nonroot_node(const struct nilfs_btree_path *path, int level)
423 {
424 return (struct nilfs_btree_node *)path[level].bp_bh->b_data;
425 }
426
427 static struct nilfs_btree_node *
428 nilfs_btree_get_sib_node(const struct nilfs_btree_path *path, int level)
429 {
430 return (struct nilfs_btree_node *)path[level].bp_sib_bh->b_data;
431 }
432
433 static int nilfs_btree_height(const struct nilfs_bmap *btree)
434 {
435 return nilfs_btree_node_get_level(nilfs_btree_get_root(btree)) + 1;
436 }
437
438 static struct nilfs_btree_node *
439 nilfs_btree_get_node(const struct nilfs_bmap *btree,
440 const struct nilfs_btree_path *path,
441 int level, int *ncmaxp)
442 {
443 struct nilfs_btree_node *node;
444
445 if (level == nilfs_btree_height(btree) - 1) {
446 node = nilfs_btree_get_root(btree);
447 *ncmaxp = NILFS_BTREE_ROOT_NCHILDREN_MAX;
448 } else {
449 node = nilfs_btree_get_nonroot_node(path, level);
450 *ncmaxp = nilfs_btree_nchildren_per_block(btree);
451 }
452 return node;
453 }
454
455 static int
456 nilfs_btree_bad_node(struct nilfs_btree_node *node, int level)
457 {
458 if (unlikely(nilfs_btree_node_get_level(node) != level)) {
459 dump_stack();
460 printk(KERN_CRIT "NILFS: btree level mismatch: %d != %d\n",
461 nilfs_btree_node_get_level(node), level);
462 return 1;
463 }
464 return 0;
465 }
466
467 struct nilfs_btree_readahead_info {
468 struct nilfs_btree_node *node; /* parent node */
469 int max_ra_blocks; /* max nof blocks to read ahead */
470 int index; /* current index on the parent node */
471 int ncmax; /* nof children in the parent node */
472 };
473
474 static int __nilfs_btree_get_block(const struct nilfs_bmap *btree, __u64 ptr,
475 struct buffer_head **bhp,
476 const struct nilfs_btree_readahead_info *ra)
477 {
478 struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
479 struct buffer_head *bh, *ra_bh;
480 sector_t submit_ptr = 0;
481 int ret;
482
483 ret = nilfs_btnode_submit_block(btnc, ptr, 0, READ, &bh, &submit_ptr);
484 if (ret) {
485 if (ret != -EEXIST)
486 return ret;
487 goto out_check;
488 }
489
490 if (ra) {
491 int i, n;
492 __u64 ptr2;
493
494 /* read ahead sibling nodes */
495 for (n = ra->max_ra_blocks, i = ra->index + 1;
496 n > 0 && i < ra->ncmax; n--, i++) {
497 ptr2 = nilfs_btree_node_get_ptr(ra->node, i, ra->ncmax);
498
499 ret = nilfs_btnode_submit_block(btnc, ptr2, 0, READA,
500 &ra_bh, &submit_ptr);
501 if (likely(!ret || ret == -EEXIST))
502 brelse(ra_bh);
503 else if (ret != -EBUSY)
504 break;
505 if (!buffer_locked(bh))
506 goto out_no_wait;
507 }
508 }
509
510 wait_on_buffer(bh);
511
512 out_no_wait:
513 if (!buffer_uptodate(bh)) {
514 brelse(bh);
515 return -EIO;
516 }
517
518 out_check:
519 if (nilfs_btree_broken_node_block(bh)) {
520 clear_buffer_uptodate(bh);
521 brelse(bh);
522 return -EINVAL;
523 }
524
525 *bhp = bh;
526 return 0;
527 }
528
529 static int nilfs_btree_get_block(const struct nilfs_bmap *btree, __u64 ptr,
530 struct buffer_head **bhp)
531 {
532 return __nilfs_btree_get_block(btree, ptr, bhp, NULL);
533 }
534
535 static int nilfs_btree_do_lookup(const struct nilfs_bmap *btree,
536 struct nilfs_btree_path *path,
537 __u64 key, __u64 *ptrp, int minlevel,
538 int readahead)
539 {
540 struct nilfs_btree_node *node;
541 struct nilfs_btree_readahead_info p, *ra;
542 __u64 ptr;
543 int level, index, found, ncmax, ret;
544
545 node = nilfs_btree_get_root(btree);
546 level = nilfs_btree_node_get_level(node);
547 if (level < minlevel || nilfs_btree_node_get_nchildren(node) <= 0)
548 return -ENOENT;
549
550 found = nilfs_btree_node_lookup(node, key, &index);
551 ptr = nilfs_btree_node_get_ptr(node, index,
552 NILFS_BTREE_ROOT_NCHILDREN_MAX);
553 path[level].bp_bh = NULL;
554 path[level].bp_index = index;
555
556 ncmax = nilfs_btree_nchildren_per_block(btree);
557
558 while (--level >= minlevel) {
559 ra = NULL;
560 if (level == NILFS_BTREE_LEVEL_NODE_MIN && readahead) {
561 p.node = nilfs_btree_get_node(btree, path, level + 1,
562 &p.ncmax);
563 p.index = index;
564 p.max_ra_blocks = 7;
565 ra = &p;
566 }
567 ret = __nilfs_btree_get_block(btree, ptr, &path[level].bp_bh,
568 ra);
569 if (ret < 0)
570 return ret;
571
572 node = nilfs_btree_get_nonroot_node(path, level);
573 if (nilfs_btree_bad_node(node, level))
574 return -EINVAL;
575 if (!found)
576 found = nilfs_btree_node_lookup(node, key, &index);
577 else
578 index = 0;
579 if (index < ncmax) {
580 ptr = nilfs_btree_node_get_ptr(node, index, ncmax);
581 } else {
582 WARN_ON(found || level != NILFS_BTREE_LEVEL_NODE_MIN);
583 /* insert */
584 ptr = NILFS_BMAP_INVALID_PTR;
585 }
586 path[level].bp_index = index;
587 }
588 if (!found)
589 return -ENOENT;
590
591 if (ptrp != NULL)
592 *ptrp = ptr;
593
594 return 0;
595 }
596
597 static int nilfs_btree_do_lookup_last(const struct nilfs_bmap *btree,
598 struct nilfs_btree_path *path,
599 __u64 *keyp, __u64 *ptrp)
600 {
601 struct nilfs_btree_node *node;
602 __u64 ptr;
603 int index, level, ncmax, ret;
604
605 node = nilfs_btree_get_root(btree);
606 index = nilfs_btree_node_get_nchildren(node) - 1;
607 if (index < 0)
608 return -ENOENT;
609 level = nilfs_btree_node_get_level(node);
610 ptr = nilfs_btree_node_get_ptr(node, index,
611 NILFS_BTREE_ROOT_NCHILDREN_MAX);
612 path[level].bp_bh = NULL;
613 path[level].bp_index = index;
614 ncmax = nilfs_btree_nchildren_per_block(btree);
615
616 for (level--; level > 0; level--) {
617 ret = nilfs_btree_get_block(btree, ptr, &path[level].bp_bh);
618 if (ret < 0)
619 return ret;
620 node = nilfs_btree_get_nonroot_node(path, level);
621 if (nilfs_btree_bad_node(node, level))
622 return -EINVAL;
623 index = nilfs_btree_node_get_nchildren(node) - 1;
624 ptr = nilfs_btree_node_get_ptr(node, index, ncmax);
625 path[level].bp_index = index;
626 }
627
628 if (keyp != NULL)
629 *keyp = nilfs_btree_node_get_key(node, index);
630 if (ptrp != NULL)
631 *ptrp = ptr;
632
633 return 0;
634 }
635
636 /**
637 * nilfs_btree_get_next_key - get next valid key from btree path array
638 * @btree: bmap struct of btree
639 * @path: array of nilfs_btree_path struct
640 * @minlevel: start level
641 * @nextkey: place to store the next valid key
642 *
643 * Return Value: If a next key was found, 0 is returned. Otherwise,
644 * -ENOENT is returned.
645 */
646 static int nilfs_btree_get_next_key(const struct nilfs_bmap *btree,
647 const struct nilfs_btree_path *path,
648 int minlevel, __u64 *nextkey)
649 {
650 struct nilfs_btree_node *node;
651 int maxlevel = nilfs_btree_height(btree) - 1;
652 int index, next_adj, level;
653
654 /* Next index is already set to bp_index for leaf nodes. */
655 next_adj = 0;
656 for (level = minlevel; level <= maxlevel; level++) {
657 if (level == maxlevel)
658 node = nilfs_btree_get_root(btree);
659 else
660 node = nilfs_btree_get_nonroot_node(path, level);
661
662 index = path[level].bp_index + next_adj;
663 if (index < nilfs_btree_node_get_nchildren(node)) {
664 /* Next key is in this node */
665 *nextkey = nilfs_btree_node_get_key(node, index);
666 return 0;
667 }
668 /* For non-leaf nodes, next index is stored at bp_index + 1. */
669 next_adj = 1;
670 }
671 return -ENOENT;
672 }
673
674 static int nilfs_btree_lookup(const struct nilfs_bmap *btree,
675 __u64 key, int level, __u64 *ptrp)
676 {
677 struct nilfs_btree_path *path;
678 int ret;
679
680 path = nilfs_btree_alloc_path();
681 if (path == NULL)
682 return -ENOMEM;
683
684 ret = nilfs_btree_do_lookup(btree, path, key, ptrp, level, 0);
685
686 nilfs_btree_free_path(path);
687
688 return ret;
689 }
690
691 static int nilfs_btree_lookup_contig(const struct nilfs_bmap *btree,
692 __u64 key, __u64 *ptrp, unsigned maxblocks)
693 {
694 struct nilfs_btree_path *path;
695 struct nilfs_btree_node *node;
696 struct inode *dat = NULL;
697 __u64 ptr, ptr2;
698 sector_t blocknr;
699 int level = NILFS_BTREE_LEVEL_NODE_MIN;
700 int ret, cnt, index, maxlevel, ncmax;
701 struct nilfs_btree_readahead_info p;
702
703 path = nilfs_btree_alloc_path();
704 if (path == NULL)
705 return -ENOMEM;
706
707 ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level, 1);
708 if (ret < 0)
709 goto out;
710
711 if (NILFS_BMAP_USE_VBN(btree)) {
712 dat = nilfs_bmap_get_dat(btree);
713 ret = nilfs_dat_translate(dat, ptr, &blocknr);
714 if (ret < 0)
715 goto out;
716 ptr = blocknr;
717 }
718 cnt = 1;
719 if (cnt == maxblocks)
720 goto end;
721
722 maxlevel = nilfs_btree_height(btree) - 1;
723 node = nilfs_btree_get_node(btree, path, level, &ncmax);
724 index = path[level].bp_index + 1;
725 for (;;) {
726 while (index < nilfs_btree_node_get_nchildren(node)) {
727 if (nilfs_btree_node_get_key(node, index) !=
728 key + cnt)
729 goto end;
730 ptr2 = nilfs_btree_node_get_ptr(node, index, ncmax);
731 if (dat) {
732 ret = nilfs_dat_translate(dat, ptr2, &blocknr);
733 if (ret < 0)
734 goto out;
735 ptr2 = blocknr;
736 }
737 if (ptr2 != ptr + cnt || ++cnt == maxblocks)
738 goto end;
739 index++;
740 continue;
741 }
742 if (level == maxlevel)
743 break;
744
745 /* look-up right sibling node */
746 p.node = nilfs_btree_get_node(btree, path, level + 1, &p.ncmax);
747 p.index = path[level + 1].bp_index + 1;
748 p.max_ra_blocks = 7;
749 if (p.index >= nilfs_btree_node_get_nchildren(p.node) ||
750 nilfs_btree_node_get_key(p.node, p.index) != key + cnt)
751 break;
752 ptr2 = nilfs_btree_node_get_ptr(p.node, p.index, p.ncmax);
753 path[level + 1].bp_index = p.index;
754
755 brelse(path[level].bp_bh);
756 path[level].bp_bh = NULL;
757
758 ret = __nilfs_btree_get_block(btree, ptr2, &path[level].bp_bh,
759 &p);
760 if (ret < 0)
761 goto out;
762 node = nilfs_btree_get_nonroot_node(path, level);
763 ncmax = nilfs_btree_nchildren_per_block(btree);
764 index = 0;
765 path[level].bp_index = index;
766 }
767 end:
768 *ptrp = ptr;
769 ret = cnt;
770 out:
771 nilfs_btree_free_path(path);
772 return ret;
773 }
774
775 static void nilfs_btree_promote_key(struct nilfs_bmap *btree,
776 struct nilfs_btree_path *path,
777 int level, __u64 key)
778 {
779 if (level < nilfs_btree_height(btree) - 1) {
780 do {
781 nilfs_btree_node_set_key(
782 nilfs_btree_get_nonroot_node(path, level),
783 path[level].bp_index, key);
784 if (!buffer_dirty(path[level].bp_bh))
785 mark_buffer_dirty(path[level].bp_bh);
786 } while ((path[level].bp_index == 0) &&
787 (++level < nilfs_btree_height(btree) - 1));
788 }
789
790 /* root */
791 if (level == nilfs_btree_height(btree) - 1) {
792 nilfs_btree_node_set_key(nilfs_btree_get_root(btree),
793 path[level].bp_index, key);
794 }
795 }
796
797 static void nilfs_btree_do_insert(struct nilfs_bmap *btree,
798 struct nilfs_btree_path *path,
799 int level, __u64 *keyp, __u64 *ptrp)
800 {
801 struct nilfs_btree_node *node;
802 int ncblk;
803
804 if (level < nilfs_btree_height(btree) - 1) {
805 node = nilfs_btree_get_nonroot_node(path, level);
806 ncblk = nilfs_btree_nchildren_per_block(btree);
807 nilfs_btree_node_insert(node, path[level].bp_index,
808 *keyp, *ptrp, ncblk);
809 if (!buffer_dirty(path[level].bp_bh))
810 mark_buffer_dirty(path[level].bp_bh);
811
812 if (path[level].bp_index == 0)
813 nilfs_btree_promote_key(btree, path, level + 1,
814 nilfs_btree_node_get_key(node,
815 0));
816 } else {
817 node = nilfs_btree_get_root(btree);
818 nilfs_btree_node_insert(node, path[level].bp_index,
819 *keyp, *ptrp,
820 NILFS_BTREE_ROOT_NCHILDREN_MAX);
821 }
822 }
823
824 static void nilfs_btree_carry_left(struct nilfs_bmap *btree,
825 struct nilfs_btree_path *path,
826 int level, __u64 *keyp, __u64 *ptrp)
827 {
828 struct nilfs_btree_node *node, *left;
829 int nchildren, lnchildren, n, move, ncblk;
830
831 node = nilfs_btree_get_nonroot_node(path, level);
832 left = nilfs_btree_get_sib_node(path, level);
833 nchildren = nilfs_btree_node_get_nchildren(node);
834 lnchildren = nilfs_btree_node_get_nchildren(left);
835 ncblk = nilfs_btree_nchildren_per_block(btree);
836 move = 0;
837
838 n = (nchildren + lnchildren + 1) / 2 - lnchildren;
839 if (n > path[level].bp_index) {
840 /* move insert point */
841 n--;
842 move = 1;
843 }
844
845 nilfs_btree_node_move_left(left, node, n, ncblk, ncblk);
846
847 if (!buffer_dirty(path[level].bp_bh))
848 mark_buffer_dirty(path[level].bp_bh);
849 if (!buffer_dirty(path[level].bp_sib_bh))
850 mark_buffer_dirty(path[level].bp_sib_bh);
851
852 nilfs_btree_promote_key(btree, path, level + 1,
853 nilfs_btree_node_get_key(node, 0));
854
855 if (move) {
856 brelse(path[level].bp_bh);
857 path[level].bp_bh = path[level].bp_sib_bh;
858 path[level].bp_sib_bh = NULL;
859 path[level].bp_index += lnchildren;
860 path[level + 1].bp_index--;
861 } else {
862 brelse(path[level].bp_sib_bh);
863 path[level].bp_sib_bh = NULL;
864 path[level].bp_index -= n;
865 }
866
867 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
868 }
869
870 static void nilfs_btree_carry_right(struct nilfs_bmap *btree,
871 struct nilfs_btree_path *path,
872 int level, __u64 *keyp, __u64 *ptrp)
873 {
874 struct nilfs_btree_node *node, *right;
875 int nchildren, rnchildren, n, move, ncblk;
876
877 node = nilfs_btree_get_nonroot_node(path, level);
878 right = nilfs_btree_get_sib_node(path, level);
879 nchildren = nilfs_btree_node_get_nchildren(node);
880 rnchildren = nilfs_btree_node_get_nchildren(right);
881 ncblk = nilfs_btree_nchildren_per_block(btree);
882 move = 0;
883
884 n = (nchildren + rnchildren + 1) / 2 - rnchildren;
885 if (n > nchildren - path[level].bp_index) {
886 /* move insert point */
887 n--;
888 move = 1;
889 }
890
891 nilfs_btree_node_move_right(node, right, n, ncblk, ncblk);
892
893 if (!buffer_dirty(path[level].bp_bh))
894 mark_buffer_dirty(path[level].bp_bh);
895 if (!buffer_dirty(path[level].bp_sib_bh))
896 mark_buffer_dirty(path[level].bp_sib_bh);
897
898 path[level + 1].bp_index++;
899 nilfs_btree_promote_key(btree, path, level + 1,
900 nilfs_btree_node_get_key(right, 0));
901 path[level + 1].bp_index--;
902
903 if (move) {
904 brelse(path[level].bp_bh);
905 path[level].bp_bh = path[level].bp_sib_bh;
906 path[level].bp_sib_bh = NULL;
907 path[level].bp_index -= nilfs_btree_node_get_nchildren(node);
908 path[level + 1].bp_index++;
909 } else {
910 brelse(path[level].bp_sib_bh);
911 path[level].bp_sib_bh = NULL;
912 }
913
914 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
915 }
916
917 static void nilfs_btree_split(struct nilfs_bmap *btree,
918 struct nilfs_btree_path *path,
919 int level, __u64 *keyp, __u64 *ptrp)
920 {
921 struct nilfs_btree_node *node, *right;
922 __u64 newkey;
923 __u64 newptr;
924 int nchildren, n, move, ncblk;
925
926 node = nilfs_btree_get_nonroot_node(path, level);
927 right = nilfs_btree_get_sib_node(path, level);
928 nchildren = nilfs_btree_node_get_nchildren(node);
929 ncblk = nilfs_btree_nchildren_per_block(btree);
930 move = 0;
931
932 n = (nchildren + 1) / 2;
933 if (n > nchildren - path[level].bp_index) {
934 n--;
935 move = 1;
936 }
937
938 nilfs_btree_node_move_right(node, right, n, ncblk, ncblk);
939
940 if (!buffer_dirty(path[level].bp_bh))
941 mark_buffer_dirty(path[level].bp_bh);
942 if (!buffer_dirty(path[level].bp_sib_bh))
943 mark_buffer_dirty(path[level].bp_sib_bh);
944
945 newkey = nilfs_btree_node_get_key(right, 0);
946 newptr = path[level].bp_newreq.bpr_ptr;
947
948 if (move) {
949 path[level].bp_index -= nilfs_btree_node_get_nchildren(node);
950 nilfs_btree_node_insert(right, path[level].bp_index,
951 *keyp, *ptrp, ncblk);
952
953 *keyp = nilfs_btree_node_get_key(right, 0);
954 *ptrp = path[level].bp_newreq.bpr_ptr;
955
956 brelse(path[level].bp_bh);
957 path[level].bp_bh = path[level].bp_sib_bh;
958 path[level].bp_sib_bh = NULL;
959 } else {
960 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
961
962 *keyp = nilfs_btree_node_get_key(right, 0);
963 *ptrp = path[level].bp_newreq.bpr_ptr;
964
965 brelse(path[level].bp_sib_bh);
966 path[level].bp_sib_bh = NULL;
967 }
968
969 path[level + 1].bp_index++;
970 }
971
972 static void nilfs_btree_grow(struct nilfs_bmap *btree,
973 struct nilfs_btree_path *path,
974 int level, __u64 *keyp, __u64 *ptrp)
975 {
976 struct nilfs_btree_node *root, *child;
977 int n, ncblk;
978
979 root = nilfs_btree_get_root(btree);
980 child = nilfs_btree_get_sib_node(path, level);
981 ncblk = nilfs_btree_nchildren_per_block(btree);
982
983 n = nilfs_btree_node_get_nchildren(root);
984
985 nilfs_btree_node_move_right(root, child, n,
986 NILFS_BTREE_ROOT_NCHILDREN_MAX, ncblk);
987 nilfs_btree_node_set_level(root, level + 1);
988
989 if (!buffer_dirty(path[level].bp_sib_bh))
990 mark_buffer_dirty(path[level].bp_sib_bh);
991
992 path[level].bp_bh = path[level].bp_sib_bh;
993 path[level].bp_sib_bh = NULL;
994
995 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
996
997 *keyp = nilfs_btree_node_get_key(child, 0);
998 *ptrp = path[level].bp_newreq.bpr_ptr;
999 }
1000
1001 static __u64 nilfs_btree_find_near(const struct nilfs_bmap *btree,
1002 const struct nilfs_btree_path *path)
1003 {
1004 struct nilfs_btree_node *node;
1005 int level, ncmax;
1006
1007 if (path == NULL)
1008 return NILFS_BMAP_INVALID_PTR;
1009
1010 /* left sibling */
1011 level = NILFS_BTREE_LEVEL_NODE_MIN;
1012 if (path[level].bp_index > 0) {
1013 node = nilfs_btree_get_node(btree, path, level, &ncmax);
1014 return nilfs_btree_node_get_ptr(node,
1015 path[level].bp_index - 1,
1016 ncmax);
1017 }
1018
1019 /* parent */
1020 level = NILFS_BTREE_LEVEL_NODE_MIN + 1;
1021 if (level <= nilfs_btree_height(btree) - 1) {
1022 node = nilfs_btree_get_node(btree, path, level, &ncmax);
1023 return nilfs_btree_node_get_ptr(node, path[level].bp_index,
1024 ncmax);
1025 }
1026
1027 return NILFS_BMAP_INVALID_PTR;
1028 }
1029
1030 static __u64 nilfs_btree_find_target_v(const struct nilfs_bmap *btree,
1031 const struct nilfs_btree_path *path,
1032 __u64 key)
1033 {
1034 __u64 ptr;
1035
1036 ptr = nilfs_bmap_find_target_seq(btree, key);
1037 if (ptr != NILFS_BMAP_INVALID_PTR)
1038 /* sequential access */
1039 return ptr;
1040 else {
1041 ptr = nilfs_btree_find_near(btree, path);
1042 if (ptr != NILFS_BMAP_INVALID_PTR)
1043 /* near */
1044 return ptr;
1045 }
1046 /* block group */
1047 return nilfs_bmap_find_target_in_group(btree);
1048 }
1049
1050 static int nilfs_btree_prepare_insert(struct nilfs_bmap *btree,
1051 struct nilfs_btree_path *path,
1052 int *levelp, __u64 key, __u64 ptr,
1053 struct nilfs_bmap_stats *stats)
1054 {
1055 struct buffer_head *bh;
1056 struct nilfs_btree_node *node, *parent, *sib;
1057 __u64 sibptr;
1058 int pindex, level, ncmax, ncblk, ret;
1059 struct inode *dat = NULL;
1060
1061 stats->bs_nblocks = 0;
1062 level = NILFS_BTREE_LEVEL_DATA;
1063
1064 /* allocate a new ptr for data block */
1065 if (NILFS_BMAP_USE_VBN(btree)) {
1066 path[level].bp_newreq.bpr_ptr =
1067 nilfs_btree_find_target_v(btree, path, key);
1068 dat = nilfs_bmap_get_dat(btree);
1069 }
1070
1071 ret = nilfs_bmap_prepare_alloc_ptr(btree, &path[level].bp_newreq, dat);
1072 if (ret < 0)
1073 goto err_out_data;
1074
1075 ncblk = nilfs_btree_nchildren_per_block(btree);
1076
1077 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
1078 level < nilfs_btree_height(btree) - 1;
1079 level++) {
1080 node = nilfs_btree_get_nonroot_node(path, level);
1081 if (nilfs_btree_node_get_nchildren(node) < ncblk) {
1082 path[level].bp_op = nilfs_btree_do_insert;
1083 stats->bs_nblocks++;
1084 goto out;
1085 }
1086
1087 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1088 pindex = path[level + 1].bp_index;
1089
1090 /* left sibling */
1091 if (pindex > 0) {
1092 sibptr = nilfs_btree_node_get_ptr(parent, pindex - 1,
1093 ncmax);
1094 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1095 if (ret < 0)
1096 goto err_out_child_node;
1097 sib = (struct nilfs_btree_node *)bh->b_data;
1098 if (nilfs_btree_node_get_nchildren(sib) < ncblk) {
1099 path[level].bp_sib_bh = bh;
1100 path[level].bp_op = nilfs_btree_carry_left;
1101 stats->bs_nblocks++;
1102 goto out;
1103 } else {
1104 brelse(bh);
1105 }
1106 }
1107
1108 /* right sibling */
1109 if (pindex < nilfs_btree_node_get_nchildren(parent) - 1) {
1110 sibptr = nilfs_btree_node_get_ptr(parent, pindex + 1,
1111 ncmax);
1112 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1113 if (ret < 0)
1114 goto err_out_child_node;
1115 sib = (struct nilfs_btree_node *)bh->b_data;
1116 if (nilfs_btree_node_get_nchildren(sib) < ncblk) {
1117 path[level].bp_sib_bh = bh;
1118 path[level].bp_op = nilfs_btree_carry_right;
1119 stats->bs_nblocks++;
1120 goto out;
1121 } else {
1122 brelse(bh);
1123 }
1124 }
1125
1126 /* split */
1127 path[level].bp_newreq.bpr_ptr =
1128 path[level - 1].bp_newreq.bpr_ptr + 1;
1129 ret = nilfs_bmap_prepare_alloc_ptr(btree,
1130 &path[level].bp_newreq, dat);
1131 if (ret < 0)
1132 goto err_out_child_node;
1133 ret = nilfs_btree_get_new_block(btree,
1134 path[level].bp_newreq.bpr_ptr,
1135 &bh);
1136 if (ret < 0)
1137 goto err_out_curr_node;
1138
1139 stats->bs_nblocks++;
1140
1141 sib = (struct nilfs_btree_node *)bh->b_data;
1142 nilfs_btree_node_init(sib, 0, level, 0, ncblk, NULL, NULL);
1143 path[level].bp_sib_bh = bh;
1144 path[level].bp_op = nilfs_btree_split;
1145 }
1146
1147 /* root */
1148 node = nilfs_btree_get_root(btree);
1149 if (nilfs_btree_node_get_nchildren(node) <
1150 NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1151 path[level].bp_op = nilfs_btree_do_insert;
1152 stats->bs_nblocks++;
1153 goto out;
1154 }
1155
1156 /* grow */
1157 path[level].bp_newreq.bpr_ptr = path[level - 1].bp_newreq.bpr_ptr + 1;
1158 ret = nilfs_bmap_prepare_alloc_ptr(btree, &path[level].bp_newreq, dat);
1159 if (ret < 0)
1160 goto err_out_child_node;
1161 ret = nilfs_btree_get_new_block(btree, path[level].bp_newreq.bpr_ptr,
1162 &bh);
1163 if (ret < 0)
1164 goto err_out_curr_node;
1165
1166 nilfs_btree_node_init((struct nilfs_btree_node *)bh->b_data,
1167 0, level, 0, ncblk, NULL, NULL);
1168 path[level].bp_sib_bh = bh;
1169 path[level].bp_op = nilfs_btree_grow;
1170
1171 level++;
1172 path[level].bp_op = nilfs_btree_do_insert;
1173
1174 /* a newly-created node block and a data block are added */
1175 stats->bs_nblocks += 2;
1176
1177 /* success */
1178 out:
1179 *levelp = level;
1180 return ret;
1181
1182 /* error */
1183 err_out_curr_node:
1184 nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
1185 err_out_child_node:
1186 for (level--; level > NILFS_BTREE_LEVEL_DATA; level--) {
1187 nilfs_btnode_delete(path[level].bp_sib_bh);
1188 nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
1189
1190 }
1191
1192 nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
1193 err_out_data:
1194 *levelp = level;
1195 stats->bs_nblocks = 0;
1196 return ret;
1197 }
1198
1199 static void nilfs_btree_commit_insert(struct nilfs_bmap *btree,
1200 struct nilfs_btree_path *path,
1201 int maxlevel, __u64 key, __u64 ptr)
1202 {
1203 struct inode *dat = NULL;
1204 int level;
1205
1206 set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
1207 ptr = path[NILFS_BTREE_LEVEL_DATA].bp_newreq.bpr_ptr;
1208 if (NILFS_BMAP_USE_VBN(btree)) {
1209 nilfs_bmap_set_target_v(btree, key, ptr);
1210 dat = nilfs_bmap_get_dat(btree);
1211 }
1212
1213 for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
1214 nilfs_bmap_commit_alloc_ptr(btree,
1215 &path[level - 1].bp_newreq, dat);
1216 path[level].bp_op(btree, path, level, &key, &ptr);
1217 }
1218
1219 if (!nilfs_bmap_dirty(btree))
1220 nilfs_bmap_set_dirty(btree);
1221 }
1222
1223 static int nilfs_btree_insert(struct nilfs_bmap *btree, __u64 key, __u64 ptr)
1224 {
1225 struct nilfs_btree_path *path;
1226 struct nilfs_bmap_stats stats;
1227 int level, ret;
1228
1229 path = nilfs_btree_alloc_path();
1230 if (path == NULL)
1231 return -ENOMEM;
1232
1233 ret = nilfs_btree_do_lookup(btree, path, key, NULL,
1234 NILFS_BTREE_LEVEL_NODE_MIN, 0);
1235 if (ret != -ENOENT) {
1236 if (ret == 0)
1237 ret = -EEXIST;
1238 goto out;
1239 }
1240
1241 ret = nilfs_btree_prepare_insert(btree, path, &level, key, ptr, &stats);
1242 if (ret < 0)
1243 goto out;
1244 nilfs_btree_commit_insert(btree, path, level, key, ptr);
1245 nilfs_inode_add_blocks(btree->b_inode, stats.bs_nblocks);
1246
1247 out:
1248 nilfs_btree_free_path(path);
1249 return ret;
1250 }
1251
1252 static void nilfs_btree_do_delete(struct nilfs_bmap *btree,
1253 struct nilfs_btree_path *path,
1254 int level, __u64 *keyp, __u64 *ptrp)
1255 {
1256 struct nilfs_btree_node *node;
1257 int ncblk;
1258
1259 if (level < nilfs_btree_height(btree) - 1) {
1260 node = nilfs_btree_get_nonroot_node(path, level);
1261 ncblk = nilfs_btree_nchildren_per_block(btree);
1262 nilfs_btree_node_delete(node, path[level].bp_index,
1263 keyp, ptrp, ncblk);
1264 if (!buffer_dirty(path[level].bp_bh))
1265 mark_buffer_dirty(path[level].bp_bh);
1266 if (path[level].bp_index == 0)
1267 nilfs_btree_promote_key(btree, path, level + 1,
1268 nilfs_btree_node_get_key(node, 0));
1269 } else {
1270 node = nilfs_btree_get_root(btree);
1271 nilfs_btree_node_delete(node, path[level].bp_index,
1272 keyp, ptrp,
1273 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1274 }
1275 }
1276
1277 static void nilfs_btree_borrow_left(struct nilfs_bmap *btree,
1278 struct nilfs_btree_path *path,
1279 int level, __u64 *keyp, __u64 *ptrp)
1280 {
1281 struct nilfs_btree_node *node, *left;
1282 int nchildren, lnchildren, n, ncblk;
1283
1284 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1285
1286 node = nilfs_btree_get_nonroot_node(path, level);
1287 left = nilfs_btree_get_sib_node(path, level);
1288 nchildren = nilfs_btree_node_get_nchildren(node);
1289 lnchildren = nilfs_btree_node_get_nchildren(left);
1290 ncblk = nilfs_btree_nchildren_per_block(btree);
1291
1292 n = (nchildren + lnchildren) / 2 - nchildren;
1293
1294 nilfs_btree_node_move_right(left, node, n, ncblk, ncblk);
1295
1296 if (!buffer_dirty(path[level].bp_bh))
1297 mark_buffer_dirty(path[level].bp_bh);
1298 if (!buffer_dirty(path[level].bp_sib_bh))
1299 mark_buffer_dirty(path[level].bp_sib_bh);
1300
1301 nilfs_btree_promote_key(btree, path, level + 1,
1302 nilfs_btree_node_get_key(node, 0));
1303
1304 brelse(path[level].bp_sib_bh);
1305 path[level].bp_sib_bh = NULL;
1306 path[level].bp_index += n;
1307 }
1308
1309 static void nilfs_btree_borrow_right(struct nilfs_bmap *btree,
1310 struct nilfs_btree_path *path,
1311 int level, __u64 *keyp, __u64 *ptrp)
1312 {
1313 struct nilfs_btree_node *node, *right;
1314 int nchildren, rnchildren, n, ncblk;
1315
1316 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1317
1318 node = nilfs_btree_get_nonroot_node(path, level);
1319 right = nilfs_btree_get_sib_node(path, level);
1320 nchildren = nilfs_btree_node_get_nchildren(node);
1321 rnchildren = nilfs_btree_node_get_nchildren(right);
1322 ncblk = nilfs_btree_nchildren_per_block(btree);
1323
1324 n = (nchildren + rnchildren) / 2 - nchildren;
1325
1326 nilfs_btree_node_move_left(node, right, n, ncblk, ncblk);
1327
1328 if (!buffer_dirty(path[level].bp_bh))
1329 mark_buffer_dirty(path[level].bp_bh);
1330 if (!buffer_dirty(path[level].bp_sib_bh))
1331 mark_buffer_dirty(path[level].bp_sib_bh);
1332
1333 path[level + 1].bp_index++;
1334 nilfs_btree_promote_key(btree, path, level + 1,
1335 nilfs_btree_node_get_key(right, 0));
1336 path[level + 1].bp_index--;
1337
1338 brelse(path[level].bp_sib_bh);
1339 path[level].bp_sib_bh = NULL;
1340 }
1341
1342 static void nilfs_btree_concat_left(struct nilfs_bmap *btree,
1343 struct nilfs_btree_path *path,
1344 int level, __u64 *keyp, __u64 *ptrp)
1345 {
1346 struct nilfs_btree_node *node, *left;
1347 int n, ncblk;
1348
1349 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1350
1351 node = nilfs_btree_get_nonroot_node(path, level);
1352 left = nilfs_btree_get_sib_node(path, level);
1353 ncblk = nilfs_btree_nchildren_per_block(btree);
1354
1355 n = nilfs_btree_node_get_nchildren(node);
1356
1357 nilfs_btree_node_move_left(left, node, n, ncblk, ncblk);
1358
1359 if (!buffer_dirty(path[level].bp_sib_bh))
1360 mark_buffer_dirty(path[level].bp_sib_bh);
1361
1362 nilfs_btnode_delete(path[level].bp_bh);
1363 path[level].bp_bh = path[level].bp_sib_bh;
1364 path[level].bp_sib_bh = NULL;
1365 path[level].bp_index += nilfs_btree_node_get_nchildren(left);
1366 }
1367
1368 static void nilfs_btree_concat_right(struct nilfs_bmap *btree,
1369 struct nilfs_btree_path *path,
1370 int level, __u64 *keyp, __u64 *ptrp)
1371 {
1372 struct nilfs_btree_node *node, *right;
1373 int n, ncblk;
1374
1375 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1376
1377 node = nilfs_btree_get_nonroot_node(path, level);
1378 right = nilfs_btree_get_sib_node(path, level);
1379 ncblk = nilfs_btree_nchildren_per_block(btree);
1380
1381 n = nilfs_btree_node_get_nchildren(right);
1382
1383 nilfs_btree_node_move_left(node, right, n, ncblk, ncblk);
1384
1385 if (!buffer_dirty(path[level].bp_bh))
1386 mark_buffer_dirty(path[level].bp_bh);
1387
1388 nilfs_btnode_delete(path[level].bp_sib_bh);
1389 path[level].bp_sib_bh = NULL;
1390 path[level + 1].bp_index++;
1391 }
1392
1393 static void nilfs_btree_shrink(struct nilfs_bmap *btree,
1394 struct nilfs_btree_path *path,
1395 int level, __u64 *keyp, __u64 *ptrp)
1396 {
1397 struct nilfs_btree_node *root, *child;
1398 int n, ncblk;
1399
1400 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1401
1402 root = nilfs_btree_get_root(btree);
1403 child = nilfs_btree_get_nonroot_node(path, level);
1404 ncblk = nilfs_btree_nchildren_per_block(btree);
1405
1406 nilfs_btree_node_delete(root, 0, NULL, NULL,
1407 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1408 nilfs_btree_node_set_level(root, level);
1409 n = nilfs_btree_node_get_nchildren(child);
1410 nilfs_btree_node_move_left(root, child, n,
1411 NILFS_BTREE_ROOT_NCHILDREN_MAX, ncblk);
1412
1413 nilfs_btnode_delete(path[level].bp_bh);
1414 path[level].bp_bh = NULL;
1415 }
1416
1417 static void nilfs_btree_nop(struct nilfs_bmap *btree,
1418 struct nilfs_btree_path *path,
1419 int level, __u64 *keyp, __u64 *ptrp)
1420 {
1421 }
1422
1423 static int nilfs_btree_prepare_delete(struct nilfs_bmap *btree,
1424 struct nilfs_btree_path *path,
1425 int *levelp,
1426 struct nilfs_bmap_stats *stats,
1427 struct inode *dat)
1428 {
1429 struct buffer_head *bh;
1430 struct nilfs_btree_node *node, *parent, *sib;
1431 __u64 sibptr;
1432 int pindex, dindex, level, ncmin, ncmax, ncblk, ret;
1433
1434 ret = 0;
1435 stats->bs_nblocks = 0;
1436 ncmin = NILFS_BTREE_NODE_NCHILDREN_MIN(nilfs_btree_node_size(btree));
1437 ncblk = nilfs_btree_nchildren_per_block(btree);
1438
1439 for (level = NILFS_BTREE_LEVEL_NODE_MIN, dindex = path[level].bp_index;
1440 level < nilfs_btree_height(btree) - 1;
1441 level++) {
1442 node = nilfs_btree_get_nonroot_node(path, level);
1443 path[level].bp_oldreq.bpr_ptr =
1444 nilfs_btree_node_get_ptr(node, dindex, ncblk);
1445 ret = nilfs_bmap_prepare_end_ptr(btree,
1446 &path[level].bp_oldreq, dat);
1447 if (ret < 0)
1448 goto err_out_child_node;
1449
1450 if (nilfs_btree_node_get_nchildren(node) > ncmin) {
1451 path[level].bp_op = nilfs_btree_do_delete;
1452 stats->bs_nblocks++;
1453 goto out;
1454 }
1455
1456 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1457 pindex = path[level + 1].bp_index;
1458 dindex = pindex;
1459
1460 if (pindex > 0) {
1461 /* left sibling */
1462 sibptr = nilfs_btree_node_get_ptr(parent, pindex - 1,
1463 ncmax);
1464 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1465 if (ret < 0)
1466 goto err_out_curr_node;
1467 sib = (struct nilfs_btree_node *)bh->b_data;
1468 if (nilfs_btree_node_get_nchildren(sib) > ncmin) {
1469 path[level].bp_sib_bh = bh;
1470 path[level].bp_op = nilfs_btree_borrow_left;
1471 stats->bs_nblocks++;
1472 goto out;
1473 } else {
1474 path[level].bp_sib_bh = bh;
1475 path[level].bp_op = nilfs_btree_concat_left;
1476 stats->bs_nblocks++;
1477 /* continue; */
1478 }
1479 } else if (pindex <
1480 nilfs_btree_node_get_nchildren(parent) - 1) {
1481 /* right sibling */
1482 sibptr = nilfs_btree_node_get_ptr(parent, pindex + 1,
1483 ncmax);
1484 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1485 if (ret < 0)
1486 goto err_out_curr_node;
1487 sib = (struct nilfs_btree_node *)bh->b_data;
1488 if (nilfs_btree_node_get_nchildren(sib) > ncmin) {
1489 path[level].bp_sib_bh = bh;
1490 path[level].bp_op = nilfs_btree_borrow_right;
1491 stats->bs_nblocks++;
1492 goto out;
1493 } else {
1494 path[level].bp_sib_bh = bh;
1495 path[level].bp_op = nilfs_btree_concat_right;
1496 stats->bs_nblocks++;
1497 /*
1498 * When merging right sibling node
1499 * into the current node, pointer to
1500 * the right sibling node must be
1501 * terminated instead. The adjustment
1502 * below is required for that.
1503 */
1504 dindex = pindex + 1;
1505 /* continue; */
1506 }
1507 } else {
1508 /* no siblings */
1509 /* the only child of the root node */
1510 WARN_ON(level != nilfs_btree_height(btree) - 2);
1511 if (nilfs_btree_node_get_nchildren(node) - 1 <=
1512 NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1513 path[level].bp_op = nilfs_btree_shrink;
1514 stats->bs_nblocks += 2;
1515 level++;
1516 path[level].bp_op = nilfs_btree_nop;
1517 goto shrink_root_child;
1518 } else {
1519 path[level].bp_op = nilfs_btree_do_delete;
1520 stats->bs_nblocks++;
1521 goto out;
1522 }
1523 }
1524 }
1525
1526 /* child of the root node is deleted */
1527 path[level].bp_op = nilfs_btree_do_delete;
1528 stats->bs_nblocks++;
1529
1530 shrink_root_child:
1531 node = nilfs_btree_get_root(btree);
1532 path[level].bp_oldreq.bpr_ptr =
1533 nilfs_btree_node_get_ptr(node, dindex,
1534 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1535
1536 ret = nilfs_bmap_prepare_end_ptr(btree, &path[level].bp_oldreq, dat);
1537 if (ret < 0)
1538 goto err_out_child_node;
1539
1540 /* success */
1541 out:
1542 *levelp = level;
1543 return ret;
1544
1545 /* error */
1546 err_out_curr_node:
1547 nilfs_bmap_abort_end_ptr(btree, &path[level].bp_oldreq, dat);
1548 err_out_child_node:
1549 for (level--; level >= NILFS_BTREE_LEVEL_NODE_MIN; level--) {
1550 brelse(path[level].bp_sib_bh);
1551 nilfs_bmap_abort_end_ptr(btree, &path[level].bp_oldreq, dat);
1552 }
1553 *levelp = level;
1554 stats->bs_nblocks = 0;
1555 return ret;
1556 }
1557
1558 static void nilfs_btree_commit_delete(struct nilfs_bmap *btree,
1559 struct nilfs_btree_path *path,
1560 int maxlevel, struct inode *dat)
1561 {
1562 int level;
1563
1564 for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
1565 nilfs_bmap_commit_end_ptr(btree, &path[level].bp_oldreq, dat);
1566 path[level].bp_op(btree, path, level, NULL, NULL);
1567 }
1568
1569 if (!nilfs_bmap_dirty(btree))
1570 nilfs_bmap_set_dirty(btree);
1571 }
1572
1573 static int nilfs_btree_delete(struct nilfs_bmap *btree, __u64 key)
1574
1575 {
1576 struct nilfs_btree_path *path;
1577 struct nilfs_bmap_stats stats;
1578 struct inode *dat;
1579 int level, ret;
1580
1581 path = nilfs_btree_alloc_path();
1582 if (path == NULL)
1583 return -ENOMEM;
1584
1585 ret = nilfs_btree_do_lookup(btree, path, key, NULL,
1586 NILFS_BTREE_LEVEL_NODE_MIN, 0);
1587 if (ret < 0)
1588 goto out;
1589
1590
1591 dat = NILFS_BMAP_USE_VBN(btree) ? nilfs_bmap_get_dat(btree) : NULL;
1592
1593 ret = nilfs_btree_prepare_delete(btree, path, &level, &stats, dat);
1594 if (ret < 0)
1595 goto out;
1596 nilfs_btree_commit_delete(btree, path, level, dat);
1597 nilfs_inode_sub_blocks(btree->b_inode, stats.bs_nblocks);
1598
1599 out:
1600 nilfs_btree_free_path(path);
1601 return ret;
1602 }
1603
1604 static int nilfs_btree_seek_key(const struct nilfs_bmap *btree, __u64 start,
1605 __u64 *keyp)
1606 {
1607 struct nilfs_btree_path *path;
1608 const int minlevel = NILFS_BTREE_LEVEL_NODE_MIN;
1609 int ret;
1610
1611 path = nilfs_btree_alloc_path();
1612 if (!path)
1613 return -ENOMEM;
1614
1615 ret = nilfs_btree_do_lookup(btree, path, start, NULL, minlevel, 0);
1616 if (!ret)
1617 *keyp = start;
1618 else if (ret == -ENOENT)
1619 ret = nilfs_btree_get_next_key(btree, path, minlevel, keyp);
1620
1621 nilfs_btree_free_path(path);
1622 return ret;
1623 }
1624
1625 static int nilfs_btree_last_key(const struct nilfs_bmap *btree, __u64 *keyp)
1626 {
1627 struct nilfs_btree_path *path;
1628 int ret;
1629
1630 path = nilfs_btree_alloc_path();
1631 if (path == NULL)
1632 return -ENOMEM;
1633
1634 ret = nilfs_btree_do_lookup_last(btree, path, keyp, NULL);
1635
1636 nilfs_btree_free_path(path);
1637
1638 return ret;
1639 }
1640
1641 static int nilfs_btree_check_delete(struct nilfs_bmap *btree, __u64 key)
1642 {
1643 struct buffer_head *bh;
1644 struct nilfs_btree_node *root, *node;
1645 __u64 maxkey, nextmaxkey;
1646 __u64 ptr;
1647 int nchildren, ret;
1648
1649 root = nilfs_btree_get_root(btree);
1650 switch (nilfs_btree_height(btree)) {
1651 case 2:
1652 bh = NULL;
1653 node = root;
1654 break;
1655 case 3:
1656 nchildren = nilfs_btree_node_get_nchildren(root);
1657 if (nchildren > 1)
1658 return 0;
1659 ptr = nilfs_btree_node_get_ptr(root, nchildren - 1,
1660 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1661 ret = nilfs_btree_get_block(btree, ptr, &bh);
1662 if (ret < 0)
1663 return ret;
1664 node = (struct nilfs_btree_node *)bh->b_data;
1665 break;
1666 default:
1667 return 0;
1668 }
1669
1670 nchildren = nilfs_btree_node_get_nchildren(node);
1671 maxkey = nilfs_btree_node_get_key(node, nchildren - 1);
1672 nextmaxkey = (nchildren > 1) ?
1673 nilfs_btree_node_get_key(node, nchildren - 2) : 0;
1674 if (bh != NULL)
1675 brelse(bh);
1676
1677 return (maxkey == key) && (nextmaxkey < NILFS_BMAP_LARGE_LOW);
1678 }
1679
1680 static int nilfs_btree_gather_data(struct nilfs_bmap *btree,
1681 __u64 *keys, __u64 *ptrs, int nitems)
1682 {
1683 struct buffer_head *bh;
1684 struct nilfs_btree_node *node, *root;
1685 __le64 *dkeys;
1686 __le64 *dptrs;
1687 __u64 ptr;
1688 int nchildren, ncmax, i, ret;
1689
1690 root = nilfs_btree_get_root(btree);
1691 switch (nilfs_btree_height(btree)) {
1692 case 2:
1693 bh = NULL;
1694 node = root;
1695 ncmax = NILFS_BTREE_ROOT_NCHILDREN_MAX;
1696 break;
1697 case 3:
1698 nchildren = nilfs_btree_node_get_nchildren(root);
1699 WARN_ON(nchildren > 1);
1700 ptr = nilfs_btree_node_get_ptr(root, nchildren - 1,
1701 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1702 ret = nilfs_btree_get_block(btree, ptr, &bh);
1703 if (ret < 0)
1704 return ret;
1705 node = (struct nilfs_btree_node *)bh->b_data;
1706 ncmax = nilfs_btree_nchildren_per_block(btree);
1707 break;
1708 default:
1709 node = NULL;
1710 return -EINVAL;
1711 }
1712
1713 nchildren = nilfs_btree_node_get_nchildren(node);
1714 if (nchildren < nitems)
1715 nitems = nchildren;
1716 dkeys = nilfs_btree_node_dkeys(node);
1717 dptrs = nilfs_btree_node_dptrs(node, ncmax);
1718 for (i = 0; i < nitems; i++) {
1719 keys[i] = le64_to_cpu(dkeys[i]);
1720 ptrs[i] = le64_to_cpu(dptrs[i]);
1721 }
1722
1723 if (bh != NULL)
1724 brelse(bh);
1725
1726 return nitems;
1727 }
1728
1729 static int
1730 nilfs_btree_prepare_convert_and_insert(struct nilfs_bmap *btree, __u64 key,
1731 union nilfs_bmap_ptr_req *dreq,
1732 union nilfs_bmap_ptr_req *nreq,
1733 struct buffer_head **bhp,
1734 struct nilfs_bmap_stats *stats)
1735 {
1736 struct buffer_head *bh;
1737 struct inode *dat = NULL;
1738 int ret;
1739
1740 stats->bs_nblocks = 0;
1741
1742 /* for data */
1743 /* cannot find near ptr */
1744 if (NILFS_BMAP_USE_VBN(btree)) {
1745 dreq->bpr_ptr = nilfs_btree_find_target_v(btree, NULL, key);
1746 dat = nilfs_bmap_get_dat(btree);
1747 }
1748
1749 ret = nilfs_bmap_prepare_alloc_ptr(btree, dreq, dat);
1750 if (ret < 0)
1751 return ret;
1752
1753 *bhp = NULL;
1754 stats->bs_nblocks++;
1755 if (nreq != NULL) {
1756 nreq->bpr_ptr = dreq->bpr_ptr + 1;
1757 ret = nilfs_bmap_prepare_alloc_ptr(btree, nreq, dat);
1758 if (ret < 0)
1759 goto err_out_dreq;
1760
1761 ret = nilfs_btree_get_new_block(btree, nreq->bpr_ptr, &bh);
1762 if (ret < 0)
1763 goto err_out_nreq;
1764
1765 *bhp = bh;
1766 stats->bs_nblocks++;
1767 }
1768
1769 /* success */
1770 return 0;
1771
1772 /* error */
1773 err_out_nreq:
1774 nilfs_bmap_abort_alloc_ptr(btree, nreq, dat);
1775 err_out_dreq:
1776 nilfs_bmap_abort_alloc_ptr(btree, dreq, dat);
1777 stats->bs_nblocks = 0;
1778 return ret;
1779
1780 }
1781
1782 static void
1783 nilfs_btree_commit_convert_and_insert(struct nilfs_bmap *btree,
1784 __u64 key, __u64 ptr,
1785 const __u64 *keys, const __u64 *ptrs,
1786 int n,
1787 union nilfs_bmap_ptr_req *dreq,
1788 union nilfs_bmap_ptr_req *nreq,
1789 struct buffer_head *bh)
1790 {
1791 struct nilfs_btree_node *node;
1792 struct inode *dat;
1793 __u64 tmpptr;
1794 int ncblk;
1795
1796 /* free resources */
1797 if (btree->b_ops->bop_clear != NULL)
1798 btree->b_ops->bop_clear(btree);
1799
1800 /* ptr must be a pointer to a buffer head. */
1801 set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
1802
1803 /* convert and insert */
1804 dat = NILFS_BMAP_USE_VBN(btree) ? nilfs_bmap_get_dat(btree) : NULL;
1805 __nilfs_btree_init(btree);
1806 if (nreq != NULL) {
1807 nilfs_bmap_commit_alloc_ptr(btree, dreq, dat);
1808 nilfs_bmap_commit_alloc_ptr(btree, nreq, dat);
1809
1810 /* create child node at level 1 */
1811 node = (struct nilfs_btree_node *)bh->b_data;
1812 ncblk = nilfs_btree_nchildren_per_block(btree);
1813 nilfs_btree_node_init(node, 0, 1, n, ncblk, keys, ptrs);
1814 nilfs_btree_node_insert(node, n, key, dreq->bpr_ptr, ncblk);
1815 if (!buffer_dirty(bh))
1816 mark_buffer_dirty(bh);
1817 if (!nilfs_bmap_dirty(btree))
1818 nilfs_bmap_set_dirty(btree);
1819
1820 brelse(bh);
1821
1822 /* create root node at level 2 */
1823 node = nilfs_btree_get_root(btree);
1824 tmpptr = nreq->bpr_ptr;
1825 nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 2, 1,
1826 NILFS_BTREE_ROOT_NCHILDREN_MAX,
1827 &keys[0], &tmpptr);
1828 } else {
1829 nilfs_bmap_commit_alloc_ptr(btree, dreq, dat);
1830
1831 /* create root node at level 1 */
1832 node = nilfs_btree_get_root(btree);
1833 nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 1, n,
1834 NILFS_BTREE_ROOT_NCHILDREN_MAX,
1835 keys, ptrs);
1836 nilfs_btree_node_insert(node, n, key, dreq->bpr_ptr,
1837 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1838 if (!nilfs_bmap_dirty(btree))
1839 nilfs_bmap_set_dirty(btree);
1840 }
1841
1842 if (NILFS_BMAP_USE_VBN(btree))
1843 nilfs_bmap_set_target_v(btree, key, dreq->bpr_ptr);
1844 }
1845
1846 /**
1847 * nilfs_btree_convert_and_insert -
1848 * @bmap:
1849 * @key:
1850 * @ptr:
1851 * @keys:
1852 * @ptrs:
1853 * @n:
1854 */
1855 int nilfs_btree_convert_and_insert(struct nilfs_bmap *btree,
1856 __u64 key, __u64 ptr,
1857 const __u64 *keys, const __u64 *ptrs, int n)
1858 {
1859 struct buffer_head *bh;
1860 union nilfs_bmap_ptr_req dreq, nreq, *di, *ni;
1861 struct nilfs_bmap_stats stats;
1862 int ret;
1863
1864 if (n + 1 <= NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1865 di = &dreq;
1866 ni = NULL;
1867 } else if ((n + 1) <= NILFS_BTREE_NODE_NCHILDREN_MAX(
1868 1 << btree->b_inode->i_blkbits)) {
1869 di = &dreq;
1870 ni = &nreq;
1871 } else {
1872 di = NULL;
1873 ni = NULL;
1874 BUG();
1875 }
1876
1877 ret = nilfs_btree_prepare_convert_and_insert(btree, key, di, ni, &bh,
1878 &stats);
1879 if (ret < 0)
1880 return ret;
1881 nilfs_btree_commit_convert_and_insert(btree, key, ptr, keys, ptrs, n,
1882 di, ni, bh);
1883 nilfs_inode_add_blocks(btree->b_inode, stats.bs_nblocks);
1884 return 0;
1885 }
1886
1887 static int nilfs_btree_propagate_p(struct nilfs_bmap *btree,
1888 struct nilfs_btree_path *path,
1889 int level,
1890 struct buffer_head *bh)
1891 {
1892 while ((++level < nilfs_btree_height(btree) - 1) &&
1893 !buffer_dirty(path[level].bp_bh))
1894 mark_buffer_dirty(path[level].bp_bh);
1895
1896 return 0;
1897 }
1898
1899 static int nilfs_btree_prepare_update_v(struct nilfs_bmap *btree,
1900 struct nilfs_btree_path *path,
1901 int level, struct inode *dat)
1902 {
1903 struct nilfs_btree_node *parent;
1904 int ncmax, ret;
1905
1906 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1907 path[level].bp_oldreq.bpr_ptr =
1908 nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
1909 ncmax);
1910 path[level].bp_newreq.bpr_ptr = path[level].bp_oldreq.bpr_ptr + 1;
1911 ret = nilfs_dat_prepare_update(dat, &path[level].bp_oldreq.bpr_req,
1912 &path[level].bp_newreq.bpr_req);
1913 if (ret < 0)
1914 return ret;
1915
1916 if (buffer_nilfs_node(path[level].bp_bh)) {
1917 path[level].bp_ctxt.oldkey = path[level].bp_oldreq.bpr_ptr;
1918 path[level].bp_ctxt.newkey = path[level].bp_newreq.bpr_ptr;
1919 path[level].bp_ctxt.bh = path[level].bp_bh;
1920 ret = nilfs_btnode_prepare_change_key(
1921 &NILFS_BMAP_I(btree)->i_btnode_cache,
1922 &path[level].bp_ctxt);
1923 if (ret < 0) {
1924 nilfs_dat_abort_update(dat,
1925 &path[level].bp_oldreq.bpr_req,
1926 &path[level].bp_newreq.bpr_req);
1927 return ret;
1928 }
1929 }
1930
1931 return 0;
1932 }
1933
1934 static void nilfs_btree_commit_update_v(struct nilfs_bmap *btree,
1935 struct nilfs_btree_path *path,
1936 int level, struct inode *dat)
1937 {
1938 struct nilfs_btree_node *parent;
1939 int ncmax;
1940
1941 nilfs_dat_commit_update(dat, &path[level].bp_oldreq.bpr_req,
1942 &path[level].bp_newreq.bpr_req,
1943 btree->b_ptr_type == NILFS_BMAP_PTR_VS);
1944
1945 if (buffer_nilfs_node(path[level].bp_bh)) {
1946 nilfs_btnode_commit_change_key(
1947 &NILFS_BMAP_I(btree)->i_btnode_cache,
1948 &path[level].bp_ctxt);
1949 path[level].bp_bh = path[level].bp_ctxt.bh;
1950 }
1951 set_buffer_nilfs_volatile(path[level].bp_bh);
1952
1953 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1954 nilfs_btree_node_set_ptr(parent, path[level + 1].bp_index,
1955 path[level].bp_newreq.bpr_ptr, ncmax);
1956 }
1957
1958 static void nilfs_btree_abort_update_v(struct nilfs_bmap *btree,
1959 struct nilfs_btree_path *path,
1960 int level, struct inode *dat)
1961 {
1962 nilfs_dat_abort_update(dat, &path[level].bp_oldreq.bpr_req,
1963 &path[level].bp_newreq.bpr_req);
1964 if (buffer_nilfs_node(path[level].bp_bh))
1965 nilfs_btnode_abort_change_key(
1966 &NILFS_BMAP_I(btree)->i_btnode_cache,
1967 &path[level].bp_ctxt);
1968 }
1969
1970 static int nilfs_btree_prepare_propagate_v(struct nilfs_bmap *btree,
1971 struct nilfs_btree_path *path,
1972 int minlevel, int *maxlevelp,
1973 struct inode *dat)
1974 {
1975 int level, ret;
1976
1977 level = minlevel;
1978 if (!buffer_nilfs_volatile(path[level].bp_bh)) {
1979 ret = nilfs_btree_prepare_update_v(btree, path, level, dat);
1980 if (ret < 0)
1981 return ret;
1982 }
1983 while ((++level < nilfs_btree_height(btree) - 1) &&
1984 !buffer_dirty(path[level].bp_bh)) {
1985
1986 WARN_ON(buffer_nilfs_volatile(path[level].bp_bh));
1987 ret = nilfs_btree_prepare_update_v(btree, path, level, dat);
1988 if (ret < 0)
1989 goto out;
1990 }
1991
1992 /* success */
1993 *maxlevelp = level - 1;
1994 return 0;
1995
1996 /* error */
1997 out:
1998 while (--level > minlevel)
1999 nilfs_btree_abort_update_v(btree, path, level, dat);
2000 if (!buffer_nilfs_volatile(path[level].bp_bh))
2001 nilfs_btree_abort_update_v(btree, path, level, dat);
2002 return ret;
2003 }
2004
2005 static void nilfs_btree_commit_propagate_v(struct nilfs_bmap *btree,
2006 struct nilfs_btree_path *path,
2007 int minlevel, int maxlevel,
2008 struct buffer_head *bh,
2009 struct inode *dat)
2010 {
2011 int level;
2012
2013 if (!buffer_nilfs_volatile(path[minlevel].bp_bh))
2014 nilfs_btree_commit_update_v(btree, path, minlevel, dat);
2015
2016 for (level = minlevel + 1; level <= maxlevel; level++)
2017 nilfs_btree_commit_update_v(btree, path, level, dat);
2018 }
2019
2020 static int nilfs_btree_propagate_v(struct nilfs_bmap *btree,
2021 struct nilfs_btree_path *path,
2022 int level, struct buffer_head *bh)
2023 {
2024 int maxlevel = 0, ret;
2025 struct nilfs_btree_node *parent;
2026 struct inode *dat = nilfs_bmap_get_dat(btree);
2027 __u64 ptr;
2028 int ncmax;
2029
2030 get_bh(bh);
2031 path[level].bp_bh = bh;
2032 ret = nilfs_btree_prepare_propagate_v(btree, path, level, &maxlevel,
2033 dat);
2034 if (ret < 0)
2035 goto out;
2036
2037 if (buffer_nilfs_volatile(path[level].bp_bh)) {
2038 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
2039 ptr = nilfs_btree_node_get_ptr(parent,
2040 path[level + 1].bp_index,
2041 ncmax);
2042 ret = nilfs_dat_mark_dirty(dat, ptr);
2043 if (ret < 0)
2044 goto out;
2045 }
2046
2047 nilfs_btree_commit_propagate_v(btree, path, level, maxlevel, bh, dat);
2048
2049 out:
2050 brelse(path[level].bp_bh);
2051 path[level].bp_bh = NULL;
2052 return ret;
2053 }
2054
2055 static int nilfs_btree_propagate(struct nilfs_bmap *btree,
2056 struct buffer_head *bh)
2057 {
2058 struct nilfs_btree_path *path;
2059 struct nilfs_btree_node *node;
2060 __u64 key;
2061 int level, ret;
2062
2063 WARN_ON(!buffer_dirty(bh));
2064
2065 path = nilfs_btree_alloc_path();
2066 if (path == NULL)
2067 return -ENOMEM;
2068
2069 if (buffer_nilfs_node(bh)) {
2070 node = (struct nilfs_btree_node *)bh->b_data;
2071 key = nilfs_btree_node_get_key(node, 0);
2072 level = nilfs_btree_node_get_level(node);
2073 } else {
2074 key = nilfs_bmap_data_get_key(btree, bh);
2075 level = NILFS_BTREE_LEVEL_DATA;
2076 }
2077
2078 ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1, 0);
2079 if (ret < 0) {
2080 if (unlikely(ret == -ENOENT))
2081 printk(KERN_CRIT "%s: key = %llu, level == %d\n",
2082 __func__, (unsigned long long)key, level);
2083 goto out;
2084 }
2085
2086 ret = NILFS_BMAP_USE_VBN(btree) ?
2087 nilfs_btree_propagate_v(btree, path, level, bh) :
2088 nilfs_btree_propagate_p(btree, path, level, bh);
2089
2090 out:
2091 nilfs_btree_free_path(path);
2092
2093 return ret;
2094 }
2095
2096 static int nilfs_btree_propagate_gc(struct nilfs_bmap *btree,
2097 struct buffer_head *bh)
2098 {
2099 return nilfs_dat_mark_dirty(nilfs_bmap_get_dat(btree), bh->b_blocknr);
2100 }
2101
2102 static void nilfs_btree_add_dirty_buffer(struct nilfs_bmap *btree,
2103 struct list_head *lists,
2104 struct buffer_head *bh)
2105 {
2106 struct list_head *head;
2107 struct buffer_head *cbh;
2108 struct nilfs_btree_node *node, *cnode;
2109 __u64 key, ckey;
2110 int level;
2111
2112 get_bh(bh);
2113 node = (struct nilfs_btree_node *)bh->b_data;
2114 key = nilfs_btree_node_get_key(node, 0);
2115 level = nilfs_btree_node_get_level(node);
2116 if (level < NILFS_BTREE_LEVEL_NODE_MIN ||
2117 level >= NILFS_BTREE_LEVEL_MAX) {
2118 dump_stack();
2119 printk(KERN_WARNING
2120 "%s: invalid btree level: %d (key=%llu, ino=%lu, "
2121 "blocknr=%llu)\n",
2122 __func__, level, (unsigned long long)key,
2123 NILFS_BMAP_I(btree)->vfs_inode.i_ino,
2124 (unsigned long long)bh->b_blocknr);
2125 return;
2126 }
2127
2128 list_for_each(head, &lists[level]) {
2129 cbh = list_entry(head, struct buffer_head, b_assoc_buffers);
2130 cnode = (struct nilfs_btree_node *)cbh->b_data;
2131 ckey = nilfs_btree_node_get_key(cnode, 0);
2132 if (key < ckey)
2133 break;
2134 }
2135 list_add_tail(&bh->b_assoc_buffers, head);
2136 }
2137
2138 static void nilfs_btree_lookup_dirty_buffers(struct nilfs_bmap *btree,
2139 struct list_head *listp)
2140 {
2141 struct address_space *btcache = &NILFS_BMAP_I(btree)->i_btnode_cache;
2142 struct list_head lists[NILFS_BTREE_LEVEL_MAX];
2143 struct pagevec pvec;
2144 struct buffer_head *bh, *head;
2145 pgoff_t index = 0;
2146 int level, i;
2147
2148 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
2149 level < NILFS_BTREE_LEVEL_MAX;
2150 level++)
2151 INIT_LIST_HEAD(&lists[level]);
2152
2153 pagevec_init(&pvec, 0);
2154
2155 while (pagevec_lookup_tag(&pvec, btcache, &index, PAGECACHE_TAG_DIRTY,
2156 PAGEVEC_SIZE)) {
2157 for (i = 0; i < pagevec_count(&pvec); i++) {
2158 bh = head = page_buffers(pvec.pages[i]);
2159 do {
2160 if (buffer_dirty(bh))
2161 nilfs_btree_add_dirty_buffer(btree,
2162 lists, bh);
2163 } while ((bh = bh->b_this_page) != head);
2164 }
2165 pagevec_release(&pvec);
2166 cond_resched();
2167 }
2168
2169 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
2170 level < NILFS_BTREE_LEVEL_MAX;
2171 level++)
2172 list_splice_tail(&lists[level], listp);
2173 }
2174
2175 static int nilfs_btree_assign_p(struct nilfs_bmap *btree,
2176 struct nilfs_btree_path *path,
2177 int level,
2178 struct buffer_head **bh,
2179 sector_t blocknr,
2180 union nilfs_binfo *binfo)
2181 {
2182 struct nilfs_btree_node *parent;
2183 __u64 key;
2184 __u64 ptr;
2185 int ncmax, ret;
2186
2187 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
2188 ptr = nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
2189 ncmax);
2190 if (buffer_nilfs_node(*bh)) {
2191 path[level].bp_ctxt.oldkey = ptr;
2192 path[level].bp_ctxt.newkey = blocknr;
2193 path[level].bp_ctxt.bh = *bh;
2194 ret = nilfs_btnode_prepare_change_key(
2195 &NILFS_BMAP_I(btree)->i_btnode_cache,
2196 &path[level].bp_ctxt);
2197 if (ret < 0)
2198 return ret;
2199 nilfs_btnode_commit_change_key(
2200 &NILFS_BMAP_I(btree)->i_btnode_cache,
2201 &path[level].bp_ctxt);
2202 *bh = path[level].bp_ctxt.bh;
2203 }
2204
2205 nilfs_btree_node_set_ptr(parent, path[level + 1].bp_index, blocknr,
2206 ncmax);
2207
2208 key = nilfs_btree_node_get_key(parent, path[level + 1].bp_index);
2209 /* on-disk format */
2210 binfo->bi_dat.bi_blkoff = cpu_to_le64(key);
2211 binfo->bi_dat.bi_level = level;
2212
2213 return 0;
2214 }
2215
2216 static int nilfs_btree_assign_v(struct nilfs_bmap *btree,
2217 struct nilfs_btree_path *path,
2218 int level,
2219 struct buffer_head **bh,
2220 sector_t blocknr,
2221 union nilfs_binfo *binfo)
2222 {
2223 struct nilfs_btree_node *parent;
2224 struct inode *dat = nilfs_bmap_get_dat(btree);
2225 __u64 key;
2226 __u64 ptr;
2227 union nilfs_bmap_ptr_req req;
2228 int ncmax, ret;
2229
2230 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
2231 ptr = nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
2232 ncmax);
2233 req.bpr_ptr = ptr;
2234 ret = nilfs_dat_prepare_start(dat, &req.bpr_req);
2235 if (ret < 0)
2236 return ret;
2237 nilfs_dat_commit_start(dat, &req.bpr_req, blocknr);
2238
2239 key = nilfs_btree_node_get_key(parent, path[level + 1].bp_index);
2240 /* on-disk format */
2241 binfo->bi_v.bi_vblocknr = cpu_to_le64(ptr);
2242 binfo->bi_v.bi_blkoff = cpu_to_le64(key);
2243
2244 return 0;
2245 }
2246
2247 static int nilfs_btree_assign(struct nilfs_bmap *btree,
2248 struct buffer_head **bh,
2249 sector_t blocknr,
2250 union nilfs_binfo *binfo)
2251 {
2252 struct nilfs_btree_path *path;
2253 struct nilfs_btree_node *node;
2254 __u64 key;
2255 int level, ret;
2256
2257 path = nilfs_btree_alloc_path();
2258 if (path == NULL)
2259 return -ENOMEM;
2260
2261 if (buffer_nilfs_node(*bh)) {
2262 node = (struct nilfs_btree_node *)(*bh)->b_data;
2263 key = nilfs_btree_node_get_key(node, 0);
2264 level = nilfs_btree_node_get_level(node);
2265 } else {
2266 key = nilfs_bmap_data_get_key(btree, *bh);
2267 level = NILFS_BTREE_LEVEL_DATA;
2268 }
2269
2270 ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1, 0);
2271 if (ret < 0) {
2272 WARN_ON(ret == -ENOENT);
2273 goto out;
2274 }
2275
2276 ret = NILFS_BMAP_USE_VBN(btree) ?
2277 nilfs_btree_assign_v(btree, path, level, bh, blocknr, binfo) :
2278 nilfs_btree_assign_p(btree, path, level, bh, blocknr, binfo);
2279
2280 out:
2281 nilfs_btree_free_path(path);
2282
2283 return ret;
2284 }
2285
2286 static int nilfs_btree_assign_gc(struct nilfs_bmap *btree,
2287 struct buffer_head **bh,
2288 sector_t blocknr,
2289 union nilfs_binfo *binfo)
2290 {
2291 struct nilfs_btree_node *node;
2292 __u64 key;
2293 int ret;
2294
2295 ret = nilfs_dat_move(nilfs_bmap_get_dat(btree), (*bh)->b_blocknr,
2296 blocknr);
2297 if (ret < 0)
2298 return ret;
2299
2300 if (buffer_nilfs_node(*bh)) {
2301 node = (struct nilfs_btree_node *)(*bh)->b_data;
2302 key = nilfs_btree_node_get_key(node, 0);
2303 } else
2304 key = nilfs_bmap_data_get_key(btree, *bh);
2305
2306 /* on-disk format */
2307 binfo->bi_v.bi_vblocknr = cpu_to_le64((*bh)->b_blocknr);
2308 binfo->bi_v.bi_blkoff = cpu_to_le64(key);
2309
2310 return 0;
2311 }
2312
2313 static int nilfs_btree_mark(struct nilfs_bmap *btree, __u64 key, int level)
2314 {
2315 struct buffer_head *bh;
2316 struct nilfs_btree_path *path;
2317 __u64 ptr;
2318 int ret;
2319
2320 path = nilfs_btree_alloc_path();
2321 if (path == NULL)
2322 return -ENOMEM;
2323
2324 ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level + 1, 0);
2325 if (ret < 0) {
2326 WARN_ON(ret == -ENOENT);
2327 goto out;
2328 }
2329 ret = nilfs_btree_get_block(btree, ptr, &bh);
2330 if (ret < 0) {
2331 WARN_ON(ret == -ENOENT);
2332 goto out;
2333 }
2334
2335 if (!buffer_dirty(bh))
2336 mark_buffer_dirty(bh);
2337 brelse(bh);
2338 if (!nilfs_bmap_dirty(btree))
2339 nilfs_bmap_set_dirty(btree);
2340
2341 out:
2342 nilfs_btree_free_path(path);
2343 return ret;
2344 }
2345
2346 static const struct nilfs_bmap_operations nilfs_btree_ops = {
2347 .bop_lookup = nilfs_btree_lookup,
2348 .bop_lookup_contig = nilfs_btree_lookup_contig,
2349 .bop_insert = nilfs_btree_insert,
2350 .bop_delete = nilfs_btree_delete,
2351 .bop_clear = NULL,
2352
2353 .bop_propagate = nilfs_btree_propagate,
2354
2355 .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
2356
2357 .bop_assign = nilfs_btree_assign,
2358 .bop_mark = nilfs_btree_mark,
2359
2360 .bop_seek_key = nilfs_btree_seek_key,
2361 .bop_last_key = nilfs_btree_last_key,
2362
2363 .bop_check_insert = NULL,
2364 .bop_check_delete = nilfs_btree_check_delete,
2365 .bop_gather_data = nilfs_btree_gather_data,
2366 };
2367
2368 static const struct nilfs_bmap_operations nilfs_btree_ops_gc = {
2369 .bop_lookup = NULL,
2370 .bop_lookup_contig = NULL,
2371 .bop_insert = NULL,
2372 .bop_delete = NULL,
2373 .bop_clear = NULL,
2374
2375 .bop_propagate = nilfs_btree_propagate_gc,
2376
2377 .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
2378
2379 .bop_assign = nilfs_btree_assign_gc,
2380 .bop_mark = NULL,
2381
2382 .bop_seek_key = NULL,
2383 .bop_last_key = NULL,
2384
2385 .bop_check_insert = NULL,
2386 .bop_check_delete = NULL,
2387 .bop_gather_data = NULL,
2388 };
2389
2390 static void __nilfs_btree_init(struct nilfs_bmap *bmap)
2391 {
2392 bmap->b_ops = &nilfs_btree_ops;
2393 bmap->b_nchildren_per_block =
2394 NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(bmap));
2395 }
2396
2397 int nilfs_btree_init(struct nilfs_bmap *bmap)
2398 {
2399 int ret = 0;
2400
2401 __nilfs_btree_init(bmap);
2402
2403 if (nilfs_btree_root_broken(nilfs_btree_get_root(bmap),
2404 bmap->b_inode->i_ino))
2405 ret = -EIO;
2406 return ret;
2407 }
2408
2409 void nilfs_btree_init_gc(struct nilfs_bmap *bmap)
2410 {
2411 bmap->b_ops = &nilfs_btree_ops_gc;
2412 bmap->b_nchildren_per_block =
2413 NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(bmap));
2414 }
Linux kernel - Deliverables
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