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1/*
2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3 */
4/* Reiserfs block (de)allocator, bitmap-based. */
5
6#include <linux/time.h>
7#include <linux/reiserfs_fs.h>
8#include <linux/errno.h>
9#include <linux/buffer_head.h>
10#include <linux/kernel.h>
11#include <linux/pagemap.h>
12#include <linux/vmalloc.h>
13#include <linux/reiserfs_fs_sb.h>
14#include <linux/reiserfs_fs_i.h>
15#include <linux/quotaops.h>
16
17#define PREALLOCATION_SIZE 9
18
19/* different reiserfs block allocator options */
20
21#define SB_ALLOC_OPTS(s) (REISERFS_SB(s)->s_alloc_options.bits)
22
23#define _ALLOC_concentrating_formatted_nodes 0
24#define _ALLOC_displacing_large_files 1
25#define _ALLOC_displacing_new_packing_localities 2
26#define _ALLOC_old_hashed_relocation 3
27#define _ALLOC_new_hashed_relocation 4
28#define _ALLOC_skip_busy 5
29#define _ALLOC_displace_based_on_dirid 6
30#define _ALLOC_hashed_formatted_nodes 7
31#define _ALLOC_old_way 8
32#define _ALLOC_hundredth_slices 9
33#define _ALLOC_dirid_groups 10
34#define _ALLOC_oid_groups 11
35#define _ALLOC_packing_groups 12
36
37#define concentrating_formatted_nodes(s) test_bit(_ALLOC_concentrating_formatted_nodes, &SB_ALLOC_OPTS(s))
38#define displacing_large_files(s) test_bit(_ALLOC_displacing_large_files, &SB_ALLOC_OPTS(s))
39#define displacing_new_packing_localities(s) test_bit(_ALLOC_displacing_new_packing_localities, &SB_ALLOC_OPTS(s))
40
41#define SET_OPTION(optname) \
42 do { \
43 reiserfs_info(s, "block allocator option \"%s\" is set", #optname); \
44 set_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s)); \
45 } while(0)
46#define TEST_OPTION(optname, s) \
47 test_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s))
48
49static inline void get_bit_address(struct super_block *s,
50 b_blocknr_t block,
51 unsigned int *bmap_nr,
52 unsigned int *offset)
53{
54 /* It is in the bitmap block number equal to the block
55 * number divided by the number of bits in a block. */
56 *bmap_nr = block >> (s->s_blocksize_bits + 3);
57 /* Within that bitmap block it is located at bit offset *offset. */
58 *offset = block & ((s->s_blocksize << 3) - 1);
59}
60
61int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value)
62{
63 unsigned int bmap, offset;
64 unsigned int bmap_count = reiserfs_bmap_count(s);
65
66 if (block == 0 || block >= SB_BLOCK_COUNT(s)) {
67 reiserfs_error(s, "vs-4010",
68 "block number is out of range %lu (%u)",
69 block, SB_BLOCK_COUNT(s));
70 return 0;
71 }
72
73 get_bit_address(s, block, &bmap, &offset);
74
75 /* Old format filesystem? Unlikely, but the bitmaps are all up front so
76 * we need to account for it. */
77 if (unlikely(test_bit(REISERFS_OLD_FORMAT,
78 &(REISERFS_SB(s)->s_properties)))) {
79 b_blocknr_t bmap1 = REISERFS_SB(s)->s_sbh->b_blocknr + 1;
80 if (block >= bmap1 &&
81 block <= bmap1 + bmap_count) {
82 reiserfs_error(s, "vs-4019", "bitmap block %lu(%u) "
83 "can't be freed or reused",
84 block, bmap_count);
85 return 0;
86 }
87 } else {
88 if (offset == 0) {
89 reiserfs_error(s, "vs-4020", "bitmap block %lu(%u) "
90 "can't be freed or reused",
91 block, bmap_count);
92 return 0;
93 }
94 }
95
96 if (bmap >= bmap_count) {
97 reiserfs_error(s, "vs-4030", "bitmap for requested block "
98 "is out of range: block=%lu, bitmap_nr=%u",
99 block, bmap);
100 return 0;
101 }
102
103 if (bit_value == 0 && block == SB_ROOT_BLOCK(s)) {
104 reiserfs_error(s, "vs-4050", "this is root block (%u), "
105 "it must be busy", SB_ROOT_BLOCK(s));
106 return 0;
107 }
108
109 return 1;
110}
111
112/* searches in journal structures for a given block number (bmap, off). If block
113 is found in reiserfs journal it suggests next free block candidate to test. */
114static inline int is_block_in_journal(struct super_block *s, unsigned int bmap,
115 int off, int *next)
116{
117 b_blocknr_t tmp;
118
119 if (reiserfs_in_journal(s, bmap, off, 1, &tmp)) {
120 if (tmp) { /* hint supplied */
121 *next = tmp;
122 PROC_INFO_INC(s, scan_bitmap.in_journal_hint);
123 } else {
124 (*next) = off + 1; /* inc offset to avoid looping. */
125 PROC_INFO_INC(s, scan_bitmap.in_journal_nohint);
126 }
127 PROC_INFO_INC(s, scan_bitmap.retry);
128 return 1;
129 }
130 return 0;
131}
132
133/* it searches for a window of zero bits with given minimum and maximum lengths in one bitmap
134 * block; */
135static int scan_bitmap_block(struct reiserfs_transaction_handle *th,
136 unsigned int bmap_n, int *beg, int boundary,
137 int min, int max, int unfm)
138{
139 struct super_block *s = th->t_super;
140 struct reiserfs_bitmap_info *bi = &SB_AP_BITMAP(s)[bmap_n];
141 struct buffer_head *bh;
142 int end, next;
143 int org = *beg;
144
145 BUG_ON(!th->t_trans_id);
146
147 RFALSE(bmap_n >= reiserfs_bmap_count(s), "Bitmap %u is out of "
148 "range (0..%u)", bmap_n, reiserfs_bmap_count(s) - 1);
149 PROC_INFO_INC(s, scan_bitmap.bmap);
150/* this is unclear and lacks comments, explain how journal bitmaps
151 work here for the reader. Convey a sense of the design here. What
152 is a window? */
153/* - I mean `a window of zero bits' as in description of this function - Zam. */
154
155 if (!bi) {
156 reiserfs_error(s, "jdm-4055", "NULL bitmap info pointer "
157 "for bitmap %d", bmap_n);
158 return 0;
159 }
160
161 bh = reiserfs_read_bitmap_block(s, bmap_n);
162 if (bh == NULL)
163 return 0;
164
165 while (1) {
166 cont:
167 if (bi->free_count < min) {
168 brelse(bh);
169 return 0; // No free blocks in this bitmap
170 }
171
172 /* search for a first zero bit -- beginning of a window */
173 *beg = reiserfs_find_next_zero_le_bit
174 ((unsigned long *)(bh->b_data), boundary, *beg);
175
176 if (*beg + min > boundary) { /* search for a zero bit fails or the rest of bitmap block
177 * cannot contain a zero window of minimum size */
178 brelse(bh);
179 return 0;
180 }
181
182 if (unfm && is_block_in_journal(s, bmap_n, *beg, beg))
183 continue;
184 /* first zero bit found; we check next bits */
185 for (end = *beg + 1;; end++) {
186 if (end >= *beg + max || end >= boundary
187 || reiserfs_test_le_bit(end, bh->b_data)) {
188 next = end;
189 break;
190 }
191 /* finding the other end of zero bit window requires looking into journal structures (in
192 * case of searching for free blocks for unformatted nodes) */
193 if (unfm && is_block_in_journal(s, bmap_n, end, &next))
194 break;
195 }
196
197 /* now (*beg) points to beginning of zero bits window,
198 * (end) points to one bit after the window end */
199 if (end - *beg >= min) { /* it seems we have found window of proper size */
200 int i;
201 reiserfs_prepare_for_journal(s, bh, 1);
202 /* try to set all blocks used checking are they still free */
203 for (i = *beg; i < end; i++) {
204 /* It seems that we should not check in journal again. */
205 if (reiserfs_test_and_set_le_bit
206 (i, bh->b_data)) {
207 /* bit was set by another process
208 * while we slept in prepare_for_journal() */
209 PROC_INFO_INC(s, scan_bitmap.stolen);
210 if (i >= *beg + min) { /* we can continue with smaller set of allocated blocks,
211 * if length of this set is more or equal to `min' */
212 end = i;
213 break;
214 }
215 /* otherwise we clear all bit were set ... */
216 while (--i >= *beg)
217 reiserfs_clear_le_bit
218 (i, bh->b_data);
219 reiserfs_restore_prepared_buffer(s, bh);
220 *beg = org;
221 /* ... and search again in current block from beginning */
222 goto cont;
223 }
224 }
225 bi->free_count -= (end - *beg);
226 journal_mark_dirty(th, s, bh);
227 brelse(bh);
228
229 /* free block count calculation */
230 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s),
231 1);
232 PUT_SB_FREE_BLOCKS(s, SB_FREE_BLOCKS(s) - (end - *beg));
233 journal_mark_dirty(th, s, SB_BUFFER_WITH_SB(s));
234
235 return end - (*beg);
236 } else {
237 *beg = next;
238 }
239 }
240}
241
242static int bmap_hash_id(struct super_block *s, u32 id)
243{
244 char *hash_in = NULL;
245 unsigned long hash;
246 unsigned bm;
247
248 if (id <= 2) {
249 bm = 1;
250 } else {
251 hash_in = (char *)(&id);
252 hash = keyed_hash(hash_in, 4);
253 bm = hash % reiserfs_bmap_count(s);
254 if (!bm)
255 bm = 1;
256 }
257 /* this can only be true when SB_BMAP_NR = 1 */
258 if (bm >= reiserfs_bmap_count(s))
259 bm = 0;
260 return bm;
261}
262
263/*
264 * hashes the id and then returns > 0 if the block group for the
265 * corresponding hash is full
266 */
267static inline int block_group_used(struct super_block *s, u32 id)
268{
269 int bm = bmap_hash_id(s, id);
270 struct reiserfs_bitmap_info *info = &SB_AP_BITMAP(s)[bm];
271
272 /* If we don't have cached information on this bitmap block, we're
273 * going to have to load it later anyway. Loading it here allows us
274 * to make a better decision. This favors long-term performance gain
275 * with a better on-disk layout vs. a short term gain of skipping the
276 * read and potentially having a bad placement. */
277 if (info->free_count == UINT_MAX) {
278 struct buffer_head *bh = reiserfs_read_bitmap_block(s, bm);
279 brelse(bh);
280 }
281
282 if (info->free_count > ((s->s_blocksize << 3) * 60 / 100)) {
283 return 0;
284 }
285 return 1;
286}
287
288/*
289 * the packing is returned in disk byte order
290 */
291__le32 reiserfs_choose_packing(struct inode * dir)
292{
293 __le32 packing;
294 if (TEST_OPTION(packing_groups, dir->i_sb)) {
295 u32 parent_dir = le32_to_cpu(INODE_PKEY(dir)->k_dir_id);
296 /*
297 * some versions of reiserfsck expect packing locality 1 to be
298 * special
299 */
300 if (parent_dir == 1 || block_group_used(dir->i_sb, parent_dir))
301 packing = INODE_PKEY(dir)->k_objectid;
302 else
303 packing = INODE_PKEY(dir)->k_dir_id;
304 } else
305 packing = INODE_PKEY(dir)->k_objectid;
306 return packing;
307}
308
309/* Tries to find contiguous zero bit window (given size) in given region of
310 * bitmap and place new blocks there. Returns number of allocated blocks. */
311static int scan_bitmap(struct reiserfs_transaction_handle *th,
312 b_blocknr_t * start, b_blocknr_t finish,
313 int min, int max, int unfm, sector_t file_block)
314{
315 int nr_allocated = 0;
316 struct super_block *s = th->t_super;
317 /* find every bm and bmap and bmap_nr in this file, and change them all to bitmap_blocknr
318 * - Hans, it is not a block number - Zam. */
319
320 unsigned int bm, off;
321 unsigned int end_bm, end_off;
322 unsigned int off_max = s->s_blocksize << 3;
323
324 BUG_ON(!th->t_trans_id);
325
326 PROC_INFO_INC(s, scan_bitmap.call);
327 if (SB_FREE_BLOCKS(s) <= 0)
328 return 0; // No point in looking for more free blocks
329
330 get_bit_address(s, *start, &bm, &off);
331 get_bit_address(s, finish, &end_bm, &end_off);
332 if (bm > reiserfs_bmap_count(s))
333 return 0;
334 if (end_bm > reiserfs_bmap_count(s))
335 end_bm = reiserfs_bmap_count(s);
336
337 /* When the bitmap is more than 10% free, anyone can allocate.
338 * When it's less than 10% free, only files that already use the
339 * bitmap are allowed. Once we pass 80% full, this restriction
340 * is lifted.
341 *
342 * We do this so that files that grow later still have space close to
343 * their original allocation. This improves locality, and presumably
344 * performance as a result.
345 *
346 * This is only an allocation policy and does not make up for getting a
347 * bad hint. Decent hinting must be implemented for this to work well.
348 */
349 if (TEST_OPTION(skip_busy, s)
350 && SB_FREE_BLOCKS(s) > SB_BLOCK_COUNT(s) / 20) {
351 for (; bm < end_bm; bm++, off = 0) {
352 if ((off && (!unfm || (file_block != 0)))
353 || SB_AP_BITMAP(s)[bm].free_count >
354 (s->s_blocksize << 3) / 10)
355 nr_allocated =
356 scan_bitmap_block(th, bm, &off, off_max,
357 min, max, unfm);
358 if (nr_allocated)
359 goto ret;
360 }
361 /* we know from above that start is a reasonable number */
362 get_bit_address(s, *start, &bm, &off);
363 }
364
365 for (; bm < end_bm; bm++, off = 0) {
366 nr_allocated =
367 scan_bitmap_block(th, bm, &off, off_max, min, max, unfm);
368 if (nr_allocated)
369 goto ret;
370 }
371
372 nr_allocated =
373 scan_bitmap_block(th, bm, &off, end_off + 1, min, max, unfm);
374
375 ret:
376 *start = bm * off_max + off;
377 return nr_allocated;
378
379}
380
381static void _reiserfs_free_block(struct reiserfs_transaction_handle *th,
382 struct inode *inode, b_blocknr_t block,
383 int for_unformatted)
384{
385 struct super_block *s = th->t_super;
386 struct reiserfs_super_block *rs;
387 struct buffer_head *sbh, *bmbh;
388 struct reiserfs_bitmap_info *apbi;
389 unsigned int nr, offset;
390
391 BUG_ON(!th->t_trans_id);
392
393 PROC_INFO_INC(s, free_block);
394
395 rs = SB_DISK_SUPER_BLOCK(s);
396 sbh = SB_BUFFER_WITH_SB(s);
397 apbi = SB_AP_BITMAP(s);
398
399 get_bit_address(s, block, &nr, &offset);
400
401 if (nr >= reiserfs_bmap_count(s)) {
402 reiserfs_error(s, "vs-4075", "block %lu is out of range",
403 block);
404 return;
405 }
406
407 bmbh = reiserfs_read_bitmap_block(s, nr);
408 if (!bmbh)
409 return;
410
411 reiserfs_prepare_for_journal(s, bmbh, 1);
412
413 /* clear bit for the given block in bit map */
414 if (!reiserfs_test_and_clear_le_bit(offset, bmbh->b_data)) {
415 reiserfs_error(s, "vs-4080",
416 "block %lu: bit already cleared", block);
417 }
418 apbi[nr].free_count++;
419 journal_mark_dirty(th, s, bmbh);
420 brelse(bmbh);
421
422 reiserfs_prepare_for_journal(s, sbh, 1);
423 /* update super block */
424 set_sb_free_blocks(rs, sb_free_blocks(rs) + 1);
425
426 journal_mark_dirty(th, s, sbh);
427 if (for_unformatted)
428 dquot_free_block_nodirty(inode, 1);
429}
430
431void reiserfs_free_block(struct reiserfs_transaction_handle *th,
432 struct inode *inode, b_blocknr_t block,
433 int for_unformatted)
434{
435 struct super_block *s = th->t_super;
436 BUG_ON(!th->t_trans_id);
437
438 RFALSE(!s, "vs-4061: trying to free block on nonexistent device");
439 if (!is_reusable(s, block, 1))
440 return;
441
442 if (block > sb_block_count(REISERFS_SB(s)->s_rs)) {
443 reiserfs_error(th->t_super, "bitmap-4072",
444 "Trying to free block outside file system "
445 "boundaries (%lu > %lu)",
446 block, sb_block_count(REISERFS_SB(s)->s_rs));
447 return;
448 }
449 /* mark it before we clear it, just in case */
450 journal_mark_freed(th, s, block);
451 _reiserfs_free_block(th, inode, block, for_unformatted);
452}
453
454/* preallocated blocks don't need to be run through journal_mark_freed */
455static void reiserfs_free_prealloc_block(struct reiserfs_transaction_handle *th,
456 struct inode *inode, b_blocknr_t block)
457{
458 BUG_ON(!th->t_trans_id);
459 RFALSE(!th->t_super,
460 "vs-4060: trying to free block on nonexistent device");
461 if (!is_reusable(th->t_super, block, 1))
462 return;
463 _reiserfs_free_block(th, inode, block, 1);
464}
465
466static void __discard_prealloc(struct reiserfs_transaction_handle *th,
467 struct reiserfs_inode_info *ei)
468{
469 unsigned long save = ei->i_prealloc_block;
470 int dirty = 0;
471 struct inode *inode = &ei->vfs_inode;
472 BUG_ON(!th->t_trans_id);
473#ifdef CONFIG_REISERFS_CHECK
474 if (ei->i_prealloc_count < 0)
475 reiserfs_error(th->t_super, "zam-4001",
476 "inode has negative prealloc blocks count.");
477#endif
478 while (ei->i_prealloc_count > 0) {
479 reiserfs_free_prealloc_block(th, inode, ei->i_prealloc_block);
480 ei->i_prealloc_block++;
481 ei->i_prealloc_count--;
482 dirty = 1;
483 }
484 if (dirty)
485 reiserfs_update_sd(th, inode);
486 ei->i_prealloc_block = save;
487 list_del_init(&(ei->i_prealloc_list));
488}
489
490/* FIXME: It should be inline function */
491void reiserfs_discard_prealloc(struct reiserfs_transaction_handle *th,
492 struct inode *inode)
493{
494 struct reiserfs_inode_info *ei = REISERFS_I(inode);
495 BUG_ON(!th->t_trans_id);
496 if (ei->i_prealloc_count)
497 __discard_prealloc(th, ei);
498}
499
500void reiserfs_discard_all_prealloc(struct reiserfs_transaction_handle *th)
501{
502 struct list_head *plist = &SB_JOURNAL(th->t_super)->j_prealloc_list;
503
504 BUG_ON(!th->t_trans_id);
505
506 while (!list_empty(plist)) {
507 struct reiserfs_inode_info *ei;
508 ei = list_entry(plist->next, struct reiserfs_inode_info,
509 i_prealloc_list);
510#ifdef CONFIG_REISERFS_CHECK
511 if (!ei->i_prealloc_count) {
512 reiserfs_error(th->t_super, "zam-4001",
513 "inode is in prealloc list but has "
514 "no preallocated blocks.");
515 }
516#endif
517 __discard_prealloc(th, ei);
518 }
519}
520
521void reiserfs_init_alloc_options(struct super_block *s)
522{
523 set_bit(_ALLOC_skip_busy, &SB_ALLOC_OPTS(s));
524 set_bit(_ALLOC_dirid_groups, &SB_ALLOC_OPTS(s));
525 set_bit(_ALLOC_packing_groups, &SB_ALLOC_OPTS(s));
526}
527
528/* block allocator related options are parsed here */
529int reiserfs_parse_alloc_options(struct super_block *s, char *options)
530{
531 char *this_char, *value;
532
533 REISERFS_SB(s)->s_alloc_options.bits = 0; /* clear default settings */
534
535 while ((this_char = strsep(&options, ":")) != NULL) {
536 if ((value = strchr(this_char, '=')) != NULL)
537 *value++ = 0;
538
539 if (!strcmp(this_char, "concentrating_formatted_nodes")) {
540 int temp;
541 SET_OPTION(concentrating_formatted_nodes);
542 temp = (value
543 && *value) ? simple_strtoul(value, &value,
544 0) : 10;
545 if (temp <= 0 || temp > 100) {
546 REISERFS_SB(s)->s_alloc_options.border = 10;
547 } else {
548 REISERFS_SB(s)->s_alloc_options.border =
549 100 / temp;
550 }
551 continue;
552 }
553 if (!strcmp(this_char, "displacing_large_files")) {
554 SET_OPTION(displacing_large_files);
555 REISERFS_SB(s)->s_alloc_options.large_file_size =
556 (value
557 && *value) ? simple_strtoul(value, &value, 0) : 16;
558 continue;
559 }
560 if (!strcmp(this_char, "displacing_new_packing_localities")) {
561 SET_OPTION(displacing_new_packing_localities);
562 continue;
563 };
564
565 if (!strcmp(this_char, "old_hashed_relocation")) {
566 SET_OPTION(old_hashed_relocation);
567 continue;
568 }
569
570 if (!strcmp(this_char, "new_hashed_relocation")) {
571 SET_OPTION(new_hashed_relocation);
572 continue;
573 }
574
575 if (!strcmp(this_char, "dirid_groups")) {
576 SET_OPTION(dirid_groups);
577 continue;
578 }
579 if (!strcmp(this_char, "oid_groups")) {
580 SET_OPTION(oid_groups);
581 continue;
582 }
583 if (!strcmp(this_char, "packing_groups")) {
584 SET_OPTION(packing_groups);
585 continue;
586 }
587 if (!strcmp(this_char, "hashed_formatted_nodes")) {
588 SET_OPTION(hashed_formatted_nodes);
589 continue;
590 }
591
592 if (!strcmp(this_char, "skip_busy")) {
593 SET_OPTION(skip_busy);
594 continue;
595 }
596
597 if (!strcmp(this_char, "hundredth_slices")) {
598 SET_OPTION(hundredth_slices);
599 continue;
600 }
601
602 if (!strcmp(this_char, "old_way")) {
603 SET_OPTION(old_way);
604 continue;
605 }
606
607 if (!strcmp(this_char, "displace_based_on_dirid")) {
608 SET_OPTION(displace_based_on_dirid);
609 continue;
610 }
611
612 if (!strcmp(this_char, "preallocmin")) {
613 REISERFS_SB(s)->s_alloc_options.preallocmin =
614 (value
615 && *value) ? simple_strtoul(value, &value, 0) : 4;
616 continue;
617 }
618
619 if (!strcmp(this_char, "preallocsize")) {
620 REISERFS_SB(s)->s_alloc_options.preallocsize =
621 (value
622 && *value) ? simple_strtoul(value, &value,
623 0) :
624 PREALLOCATION_SIZE;
625 continue;
626 }
627
628 reiserfs_warning(s, "zam-4001", "unknown option - %s",
629 this_char);
630 return 1;
631 }
632
633 reiserfs_info(s, "allocator options = [%08x]\n", SB_ALLOC_OPTS(s));
634 return 0;
635}
636
637static inline void new_hashed_relocation(reiserfs_blocknr_hint_t * hint)
638{
639 char *hash_in;
640 if (hint->formatted_node) {
641 hash_in = (char *)&hint->key.k_dir_id;
642 } else {
643 if (!hint->inode) {
644 //hint->search_start = hint->beg;
645 hash_in = (char *)&hint->key.k_dir_id;
646 } else
647 if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
648 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
649 else
650 hash_in =
651 (char *)(&INODE_PKEY(hint->inode)->k_objectid);
652 }
653
654 hint->search_start =
655 hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
656}
657
658/*
659 * Relocation based on dirid, hashing them into a given bitmap block
660 * files. Formatted nodes are unaffected, a separate policy covers them
661 */
662static void dirid_groups(reiserfs_blocknr_hint_t * hint)
663{
664 unsigned long hash;
665 __u32 dirid = 0;
666 int bm = 0;
667 struct super_block *sb = hint->th->t_super;
668 if (hint->inode)
669 dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
670 else if (hint->formatted_node)
671 dirid = hint->key.k_dir_id;
672
673 if (dirid) {
674 bm = bmap_hash_id(sb, dirid);
675 hash = bm * (sb->s_blocksize << 3);
676 /* give a portion of the block group to metadata */
677 if (hint->inode)
678 hash += sb->s_blocksize / 2;
679 hint->search_start = hash;
680 }
681}
682
683/*
684 * Relocation based on oid, hashing them into a given bitmap block
685 * files. Formatted nodes are unaffected, a separate policy covers them
686 */
687static void oid_groups(reiserfs_blocknr_hint_t * hint)
688{
689 if (hint->inode) {
690 unsigned long hash;
691 __u32 oid;
692 __u32 dirid;
693 int bm;
694
695 dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
696
697 /* keep the root dir and it's first set of subdirs close to
698 * the start of the disk
699 */
700 if (dirid <= 2)
701 hash = (hint->inode->i_sb->s_blocksize << 3);
702 else {
703 oid = le32_to_cpu(INODE_PKEY(hint->inode)->k_objectid);
704 bm = bmap_hash_id(hint->inode->i_sb, oid);
705 hash = bm * (hint->inode->i_sb->s_blocksize << 3);
706 }
707 hint->search_start = hash;
708 }
709}
710
711/* returns 1 if it finds an indirect item and gets valid hint info
712 * from it, otherwise 0
713 */
714static int get_left_neighbor(reiserfs_blocknr_hint_t * hint)
715{
716 struct treepath *path;
717 struct buffer_head *bh;
718 struct item_head *ih;
719 int pos_in_item;
720 __le32 *item;
721 int ret = 0;
722
723 if (!hint->path) /* reiserfs code can call this function w/o pointer to path
724 * structure supplied; then we rely on supplied search_start */
725 return 0;
726
727 path = hint->path;
728 bh = get_last_bh(path);
729 RFALSE(!bh, "green-4002: Illegal path specified to get_left_neighbor");
730 ih = get_ih(path);
731 pos_in_item = path->pos_in_item;
732 item = get_item(path);
733
734 hint->search_start = bh->b_blocknr;
735
736 if (!hint->formatted_node && is_indirect_le_ih(ih)) {
737 /* for indirect item: go to left and look for the first non-hole entry
738 in the indirect item */
739 if (pos_in_item == I_UNFM_NUM(ih))
740 pos_in_item--;
741// pos_in_item = I_UNFM_NUM (ih) - 1;
742 while (pos_in_item >= 0) {
743 int t = get_block_num(item, pos_in_item);
744 if (t) {
745 hint->search_start = t;
746 ret = 1;
747 break;
748 }
749 pos_in_item--;
750 }
751 }
752
753 /* does result value fit into specified region? */
754 return ret;
755}
756
757/* should be, if formatted node, then try to put on first part of the device
758 specified as number of percent with mount option device, else try to put
759 on last of device. This is not to say it is good code to do so,
760 but the effect should be measured. */
761static inline void set_border_in_hint(struct super_block *s,
762 reiserfs_blocknr_hint_t * hint)
763{
764 b_blocknr_t border =
765 SB_BLOCK_COUNT(s) / REISERFS_SB(s)->s_alloc_options.border;
766
767 if (hint->formatted_node)
768 hint->end = border - 1;
769 else
770 hint->beg = border;
771}
772
773static inline void displace_large_file(reiserfs_blocknr_hint_t * hint)
774{
775 if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
776 hint->search_start =
777 hint->beg +
778 keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_dir_id),
779 4) % (hint->end - hint->beg);
780 else
781 hint->search_start =
782 hint->beg +
783 keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_objectid),
784 4) % (hint->end - hint->beg);
785}
786
787static inline void hash_formatted_node(reiserfs_blocknr_hint_t * hint)
788{
789 char *hash_in;
790
791 if (!hint->inode)
792 hash_in = (char *)&hint->key.k_dir_id;
793 else if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
794 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
795 else
796 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_objectid);
797
798 hint->search_start =
799 hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
800}
801
802static inline int
803this_blocknr_allocation_would_make_it_a_large_file(reiserfs_blocknr_hint_t *
804 hint)
805{
806 return hint->block ==
807 REISERFS_SB(hint->th->t_super)->s_alloc_options.large_file_size;
808}
809
810#ifdef DISPLACE_NEW_PACKING_LOCALITIES
811static inline void displace_new_packing_locality(reiserfs_blocknr_hint_t * hint)
812{
813 struct in_core_key *key = &hint->key;
814
815 hint->th->displace_new_blocks = 0;
816 hint->search_start =
817 hint->beg + keyed_hash((char *)(&key->k_objectid),
818 4) % (hint->end - hint->beg);
819}
820#endif
821
822static inline int old_hashed_relocation(reiserfs_blocknr_hint_t * hint)
823{
824 b_blocknr_t border;
825 u32 hash_in;
826
827 if (hint->formatted_node || hint->inode == NULL) {
828 return 0;
829 }
830
831 hash_in = le32_to_cpu((INODE_PKEY(hint->inode))->k_dir_id);
832 border =
833 hint->beg + (u32) keyed_hash(((char *)(&hash_in)),
834 4) % (hint->end - hint->beg - 1);
835 if (border > hint->search_start)
836 hint->search_start = border;
837
838 return 1;
839}
840
841static inline int old_way(reiserfs_blocknr_hint_t * hint)
842{
843 b_blocknr_t border;
844
845 if (hint->formatted_node || hint->inode == NULL) {
846 return 0;
847 }
848
849 border =
850 hint->beg +
851 le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id) % (hint->end -
852 hint->beg);
853 if (border > hint->search_start)
854 hint->search_start = border;
855
856 return 1;
857}
858
859static inline void hundredth_slices(reiserfs_blocknr_hint_t * hint)
860{
861 struct in_core_key *key = &hint->key;
862 b_blocknr_t slice_start;
863
864 slice_start =
865 (keyed_hash((char *)(&key->k_dir_id), 4) % 100) * (hint->end / 100);
866 if (slice_start > hint->search_start
867 || slice_start + (hint->end / 100) <= hint->search_start) {
868 hint->search_start = slice_start;
869 }
870}
871
872static void determine_search_start(reiserfs_blocknr_hint_t * hint,
873 int amount_needed)
874{
875 struct super_block *s = hint->th->t_super;
876 int unfm_hint;
877
878 hint->beg = 0;
879 hint->end = SB_BLOCK_COUNT(s) - 1;
880
881 /* This is former border algorithm. Now with tunable border offset */
882 if (concentrating_formatted_nodes(s))
883 set_border_in_hint(s, hint);
884
885#ifdef DISPLACE_NEW_PACKING_LOCALITIES
886 /* whenever we create a new directory, we displace it. At first we will
887 hash for location, later we might look for a moderately empty place for
888 it */
889 if (displacing_new_packing_localities(s)
890 && hint->th->displace_new_blocks) {
891 displace_new_packing_locality(hint);
892
893 /* we do not continue determine_search_start,
894 * if new packing locality is being displaced */
895 return;
896 }
897#endif
898
899 /* all persons should feel encouraged to add more special cases here and
900 * test them */
901
902 if (displacing_large_files(s) && !hint->formatted_node
903 && this_blocknr_allocation_would_make_it_a_large_file(hint)) {
904 displace_large_file(hint);
905 return;
906 }
907
908 /* if none of our special cases is relevant, use the left neighbor in the
909 tree order of the new node we are allocating for */
910 if (hint->formatted_node && TEST_OPTION(hashed_formatted_nodes, s)) {
911 hash_formatted_node(hint);
912 return;
913 }
914
915 unfm_hint = get_left_neighbor(hint);
916
917 /* Mimic old block allocator behaviour, that is if VFS allowed for preallocation,
918 new blocks are displaced based on directory ID. Also, if suggested search_start
919 is less than last preallocated block, we start searching from it, assuming that
920 HDD dataflow is faster in forward direction */
921 if (TEST_OPTION(old_way, s)) {
922 if (!hint->formatted_node) {
923 if (!reiserfs_hashed_relocation(s))
924 old_way(hint);
925 else if (!reiserfs_no_unhashed_relocation(s))
926 old_hashed_relocation(hint);
927
928 if (hint->inode
929 && hint->search_start <
930 REISERFS_I(hint->inode)->i_prealloc_block)
931 hint->search_start =
932 REISERFS_I(hint->inode)->i_prealloc_block;
933 }
934 return;
935 }
936
937 /* This is an approach proposed by Hans */
938 if (TEST_OPTION(hundredth_slices, s)
939 && !(displacing_large_files(s) && !hint->formatted_node)) {
940 hundredth_slices(hint);
941 return;
942 }
943
944 /* old_hashed_relocation only works on unformatted */
945 if (!unfm_hint && !hint->formatted_node &&
946 TEST_OPTION(old_hashed_relocation, s)) {
947 old_hashed_relocation(hint);
948 }
949 /* new_hashed_relocation works with both formatted/unformatted nodes */
950 if ((!unfm_hint || hint->formatted_node) &&
951 TEST_OPTION(new_hashed_relocation, s)) {
952 new_hashed_relocation(hint);
953 }
954 /* dirid grouping works only on unformatted nodes */
955 if (!unfm_hint && !hint->formatted_node && TEST_OPTION(dirid_groups, s)) {
956 dirid_groups(hint);
957 }
958#ifdef DISPLACE_NEW_PACKING_LOCALITIES
959 if (hint->formatted_node && TEST_OPTION(dirid_groups, s)) {
960 dirid_groups(hint);
961 }
962#endif
963
964 /* oid grouping works only on unformatted nodes */
965 if (!unfm_hint && !hint->formatted_node && TEST_OPTION(oid_groups, s)) {
966 oid_groups(hint);
967 }
968 return;
969}
970
971static int determine_prealloc_size(reiserfs_blocknr_hint_t * hint)
972{
973 /* make minimum size a mount option and benchmark both ways */
974 /* we preallocate blocks only for regular files, specific size */
975 /* benchmark preallocating always and see what happens */
976
977 hint->prealloc_size = 0;
978
979 if (!hint->formatted_node && hint->preallocate) {
980 if (S_ISREG(hint->inode->i_mode)
981 && hint->inode->i_size >=
982 REISERFS_SB(hint->th->t_super)->s_alloc_options.
983 preallocmin * hint->inode->i_sb->s_blocksize)
984 hint->prealloc_size =
985 REISERFS_SB(hint->th->t_super)->s_alloc_options.
986 preallocsize - 1;
987 }
988 return CARRY_ON;
989}
990
991/* XXX I know it could be merged with upper-level function;
992 but may be result function would be too complex. */
993static inline int allocate_without_wrapping_disk(reiserfs_blocknr_hint_t * hint,
994 b_blocknr_t * new_blocknrs,
995 b_blocknr_t start,
996 b_blocknr_t finish, int min,
997 int amount_needed,
998 int prealloc_size)
999{
1000 int rest = amount_needed;
1001 int nr_allocated;
1002
1003 while (rest > 0 && start <= finish) {
1004 nr_allocated = scan_bitmap(hint->th, &start, finish, min,
1005 rest + prealloc_size,
1006 !hint->formatted_node, hint->block);
1007
1008 if (nr_allocated == 0) /* no new blocks allocated, return */
1009 break;
1010
1011 /* fill free_blocknrs array first */
1012 while (rest > 0 && nr_allocated > 0) {
1013 *new_blocknrs++ = start++;
1014 rest--;
1015 nr_allocated--;
1016 }
1017
1018 /* do we have something to fill prealloc. array also ? */
1019 if (nr_allocated > 0) {
1020 /* it means prealloc_size was greater that 0 and we do preallocation */
1021 list_add(&REISERFS_I(hint->inode)->i_prealloc_list,
1022 &SB_JOURNAL(hint->th->t_super)->
1023 j_prealloc_list);
1024 REISERFS_I(hint->inode)->i_prealloc_block = start;
1025 REISERFS_I(hint->inode)->i_prealloc_count =
1026 nr_allocated;
1027 break;
1028 }
1029 }
1030
1031 return (amount_needed - rest);
1032}
1033
1034static inline int blocknrs_and_prealloc_arrays_from_search_start
1035 (reiserfs_blocknr_hint_t * hint, b_blocknr_t * new_blocknrs,
1036 int amount_needed) {
1037 struct super_block *s = hint->th->t_super;
1038 b_blocknr_t start = hint->search_start;
1039 b_blocknr_t finish = SB_BLOCK_COUNT(s) - 1;
1040 int passno = 0;
1041 int nr_allocated = 0;
1042
1043 determine_prealloc_size(hint);
1044 if (!hint->formatted_node) {
1045 int quota_ret;
1046#ifdef REISERQUOTA_DEBUG
1047 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1048 "reiserquota: allocating %d blocks id=%u",
1049 amount_needed, hint->inode->i_uid);
1050#endif
1051 quota_ret =
1052 dquot_alloc_block_nodirty(hint->inode, amount_needed);
1053 if (quota_ret) /* Quota exceeded? */
1054 return QUOTA_EXCEEDED;
1055 if (hint->preallocate && hint->prealloc_size) {
1056#ifdef REISERQUOTA_DEBUG
1057 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1058 "reiserquota: allocating (prealloc) %d blocks id=%u",
1059 hint->prealloc_size, hint->inode->i_uid);
1060#endif
1061 quota_ret = dquot_prealloc_block_nodirty(hint->inode,
1062 hint->prealloc_size);
1063 if (quota_ret)
1064 hint->preallocate = hint->prealloc_size = 0;
1065 }
1066 /* for unformatted nodes, force large allocations */
1067 }
1068
1069 do {
1070 switch (passno++) {
1071 case 0: /* Search from hint->search_start to end of disk */
1072 start = hint->search_start;
1073 finish = SB_BLOCK_COUNT(s) - 1;
1074 break;
1075 case 1: /* Search from hint->beg to hint->search_start */
1076 start = hint->beg;
1077 finish = hint->search_start;
1078 break;
1079 case 2: /* Last chance: Search from 0 to hint->beg */
1080 start = 0;
1081 finish = hint->beg;
1082 break;
1083 default: /* We've tried searching everywhere, not enough space */
1084 /* Free the blocks */
1085 if (!hint->formatted_node) {
1086#ifdef REISERQUOTA_DEBUG
1087 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1088 "reiserquota: freeing (nospace) %d blocks id=%u",
1089 amount_needed +
1090 hint->prealloc_size -
1091 nr_allocated,
1092 hint->inode->i_uid);
1093#endif
1094 /* Free not allocated blocks */
1095 dquot_free_block_nodirty(hint->inode,
1096 amount_needed + hint->prealloc_size -
1097 nr_allocated);
1098 }
1099 while (nr_allocated--)
1100 reiserfs_free_block(hint->th, hint->inode,
1101 new_blocknrs[nr_allocated],
1102 !hint->formatted_node);
1103
1104 return NO_DISK_SPACE;
1105 }
1106 } while ((nr_allocated += allocate_without_wrapping_disk(hint,
1107 new_blocknrs +
1108 nr_allocated,
1109 start, finish,
1110 1,
1111 amount_needed -
1112 nr_allocated,
1113 hint->
1114 prealloc_size))
1115 < amount_needed);
1116 if (!hint->formatted_node &&
1117 amount_needed + hint->prealloc_size >
1118 nr_allocated + REISERFS_I(hint->inode)->i_prealloc_count) {
1119 /* Some of preallocation blocks were not allocated */
1120#ifdef REISERQUOTA_DEBUG
1121 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1122 "reiserquota: freeing (failed prealloc) %d blocks id=%u",
1123 amount_needed + hint->prealloc_size -
1124 nr_allocated -
1125 REISERFS_I(hint->inode)->i_prealloc_count,
1126 hint->inode->i_uid);
1127#endif
1128 dquot_free_block_nodirty(hint->inode, amount_needed +
1129 hint->prealloc_size - nr_allocated -
1130 REISERFS_I(hint->inode)->
1131 i_prealloc_count);
1132 }
1133
1134 return CARRY_ON;
1135}
1136
1137/* grab new blocknrs from preallocated list */
1138/* return amount still needed after using them */
1139static int use_preallocated_list_if_available(reiserfs_blocknr_hint_t * hint,
1140 b_blocknr_t * new_blocknrs,
1141 int amount_needed)
1142{
1143 struct inode *inode = hint->inode;
1144
1145 if (REISERFS_I(inode)->i_prealloc_count > 0) {
1146 while (amount_needed) {
1147
1148 *new_blocknrs++ = REISERFS_I(inode)->i_prealloc_block++;
1149 REISERFS_I(inode)->i_prealloc_count--;
1150
1151 amount_needed--;
1152
1153 if (REISERFS_I(inode)->i_prealloc_count <= 0) {
1154 list_del(&REISERFS_I(inode)->i_prealloc_list);
1155 break;
1156 }
1157 }
1158 }
1159 /* return amount still needed after using preallocated blocks */
1160 return amount_needed;
1161}
1162
1163int reiserfs_allocate_blocknrs(reiserfs_blocknr_hint_t * hint, b_blocknr_t * new_blocknrs, int amount_needed, int reserved_by_us /* Amount of blocks we have
1164 already reserved */ )
1165{
1166 int initial_amount_needed = amount_needed;
1167 int ret;
1168 struct super_block *s = hint->th->t_super;
1169
1170 /* Check if there is enough space, taking into account reserved space */
1171 if (SB_FREE_BLOCKS(s) - REISERFS_SB(s)->reserved_blocks <
1172 amount_needed - reserved_by_us)
1173 return NO_DISK_SPACE;
1174 /* should this be if !hint->inode && hint->preallocate? */
1175 /* do you mean hint->formatted_node can be removed ? - Zam */
1176 /* hint->formatted_node cannot be removed because we try to access
1177 inode information here, and there is often no inode assotiated with
1178 metadata allocations - green */
1179
1180 if (!hint->formatted_node && hint->preallocate) {
1181 amount_needed = use_preallocated_list_if_available
1182 (hint, new_blocknrs, amount_needed);
1183 if (amount_needed == 0) /* all blocknrs we need we got from
1184 prealloc. list */
1185 return CARRY_ON;
1186 new_blocknrs += (initial_amount_needed - amount_needed);
1187 }
1188
1189 /* find search start and save it in hint structure */
1190 determine_search_start(hint, amount_needed);
1191 if (hint->search_start >= SB_BLOCK_COUNT(s))
1192 hint->search_start = SB_BLOCK_COUNT(s) - 1;
1193
1194 /* allocation itself; fill new_blocknrs and preallocation arrays */
1195 ret = blocknrs_and_prealloc_arrays_from_search_start
1196 (hint, new_blocknrs, amount_needed);
1197
1198 /* we used prealloc. list to fill (partially) new_blocknrs array. If final allocation fails we
1199 * need to return blocks back to prealloc. list or just free them. -- Zam (I chose second
1200 * variant) */
1201
1202 if (ret != CARRY_ON) {
1203 while (amount_needed++ < initial_amount_needed) {
1204 reiserfs_free_block(hint->th, hint->inode,
1205 *(--new_blocknrs), 1);
1206 }
1207 }
1208 return ret;
1209}
1210
1211void reiserfs_cache_bitmap_metadata(struct super_block *sb,
1212 struct buffer_head *bh,
1213 struct reiserfs_bitmap_info *info)
1214{
1215 unsigned long *cur = (unsigned long *)(bh->b_data + bh->b_size);
1216
1217 /* The first bit must ALWAYS be 1 */
1218 if (!reiserfs_test_le_bit(0, (unsigned long *)bh->b_data))
1219 reiserfs_error(sb, "reiserfs-2025", "bitmap block %lu is "
1220 "corrupted: first bit must be 1", bh->b_blocknr);
1221
1222 info->free_count = 0;
1223
1224 while (--cur >= (unsigned long *)bh->b_data) {
1225 /* 0 and ~0 are special, we can optimize for them */
1226 if (*cur == 0)
1227 info->free_count += BITS_PER_LONG;
1228 else if (*cur != ~0L) /* A mix, investigate */
1229 info->free_count += BITS_PER_LONG - hweight_long(*cur);
1230 }
1231}
1232
1233struct buffer_head *reiserfs_read_bitmap_block(struct super_block *sb,
1234 unsigned int bitmap)
1235{
1236 b_blocknr_t block = (sb->s_blocksize << 3) * bitmap;
1237 struct reiserfs_bitmap_info *info = SB_AP_BITMAP(sb) + bitmap;
1238 struct buffer_head *bh;
1239
1240 /* Way old format filesystems had the bitmaps packed up front.
1241 * I doubt there are any of these left, but just in case... */
1242 if (unlikely(test_bit(REISERFS_OLD_FORMAT,
1243 &(REISERFS_SB(sb)->s_properties))))
1244 block = REISERFS_SB(sb)->s_sbh->b_blocknr + 1 + bitmap;
1245 else if (bitmap == 0)
1246 block = (REISERFS_DISK_OFFSET_IN_BYTES >> sb->s_blocksize_bits) + 1;
1247
1248 reiserfs_write_unlock(sb);
1249 bh = sb_bread(sb, block);
1250 reiserfs_write_lock(sb);
1251 if (bh == NULL)
1252 reiserfs_warning(sb, "sh-2029: %s: bitmap block (#%u) "
1253 "reading failed", __func__, block);
1254 else {
1255 if (buffer_locked(bh)) {
1256 PROC_INFO_INC(sb, scan_bitmap.wait);
1257 reiserfs_write_unlock(sb);
1258 __wait_on_buffer(bh);
1259 reiserfs_write_lock(sb);
1260 }
1261 BUG_ON(!buffer_uptodate(bh));
1262 BUG_ON(atomic_read(&bh->b_count) == 0);
1263
1264 if (info->free_count == UINT_MAX)
1265 reiserfs_cache_bitmap_metadata(sb, bh, info);
1266 }
1267
1268 return bh;
1269}
1270
1271int reiserfs_init_bitmap_cache(struct super_block *sb)
1272{
1273 struct reiserfs_bitmap_info *bitmap;
1274 unsigned int bmap_nr = reiserfs_bmap_count(sb);
1275
1276 /* Avoid lock recursion in fault case */
1277 reiserfs_write_unlock(sb);
1278 bitmap = vmalloc(sizeof(*bitmap) * bmap_nr);
1279 reiserfs_write_lock(sb);
1280 if (bitmap == NULL)
1281 return -ENOMEM;
1282
1283 memset(bitmap, 0xff, sizeof(*bitmap) * bmap_nr);
1284
1285 SB_AP_BITMAP(sb) = bitmap;
1286
1287 return 0;
1288}
1289
1290void reiserfs_free_bitmap_cache(struct super_block *sb)
1291{
1292 if (SB_AP_BITMAP(sb)) {
1293 vfree(SB_AP_BITMAP(sb));
1294 SB_AP_BITMAP(sb) = NULL;
1295 }
1296}
1/*
2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3 */
4/* Reiserfs block (de)allocator, bitmap-based. */
5
6#include <linux/time.h>
7#include "reiserfs.h"
8#include <linux/errno.h>
9#include <linux/buffer_head.h>
10#include <linux/kernel.h>
11#include <linux/pagemap.h>
12#include <linux/vmalloc.h>
13#include <linux/quotaops.h>
14#include <linux/seq_file.h>
15
16#define PREALLOCATION_SIZE 9
17
18/* different reiserfs block allocator options */
19
20#define SB_ALLOC_OPTS(s) (REISERFS_SB(s)->s_alloc_options.bits)
21
22#define _ALLOC_concentrating_formatted_nodes 0
23#define _ALLOC_displacing_large_files 1
24#define _ALLOC_displacing_new_packing_localities 2
25#define _ALLOC_old_hashed_relocation 3
26#define _ALLOC_new_hashed_relocation 4
27#define _ALLOC_skip_busy 5
28#define _ALLOC_displace_based_on_dirid 6
29#define _ALLOC_hashed_formatted_nodes 7
30#define _ALLOC_old_way 8
31#define _ALLOC_hundredth_slices 9
32#define _ALLOC_dirid_groups 10
33#define _ALLOC_oid_groups 11
34#define _ALLOC_packing_groups 12
35
36#define concentrating_formatted_nodes(s) test_bit(_ALLOC_concentrating_formatted_nodes, &SB_ALLOC_OPTS(s))
37#define displacing_large_files(s) test_bit(_ALLOC_displacing_large_files, &SB_ALLOC_OPTS(s))
38#define displacing_new_packing_localities(s) test_bit(_ALLOC_displacing_new_packing_localities, &SB_ALLOC_OPTS(s))
39
40#define SET_OPTION(optname) \
41 do { \
42 reiserfs_info(s, "block allocator option \"%s\" is set", #optname); \
43 set_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s)); \
44 } while(0)
45#define TEST_OPTION(optname, s) \
46 test_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s))
47
48static inline void get_bit_address(struct super_block *s,
49 b_blocknr_t block,
50 unsigned int *bmap_nr,
51 unsigned int *offset)
52{
53 /*
54 * It is in the bitmap block number equal to the block
55 * number divided by the number of bits in a block.
56 */
57 *bmap_nr = block >> (s->s_blocksize_bits + 3);
58 /* Within that bitmap block it is located at bit offset *offset. */
59 *offset = block & ((s->s_blocksize << 3) - 1);
60}
61
62int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value)
63{
64 unsigned int bmap, offset;
65 unsigned int bmap_count = reiserfs_bmap_count(s);
66
67 if (block == 0 || block >= SB_BLOCK_COUNT(s)) {
68 reiserfs_error(s, "vs-4010",
69 "block number is out of range %lu (%u)",
70 block, SB_BLOCK_COUNT(s));
71 return 0;
72 }
73
74 get_bit_address(s, block, &bmap, &offset);
75
76 /*
77 * Old format filesystem? Unlikely, but the bitmaps are all
78 * up front so we need to account for it.
79 */
80 if (unlikely(test_bit(REISERFS_OLD_FORMAT,
81 &REISERFS_SB(s)->s_properties))) {
82 b_blocknr_t bmap1 = REISERFS_SB(s)->s_sbh->b_blocknr + 1;
83 if (block >= bmap1 &&
84 block <= bmap1 + bmap_count) {
85 reiserfs_error(s, "vs-4019", "bitmap block %lu(%u) "
86 "can't be freed or reused",
87 block, bmap_count);
88 return 0;
89 }
90 } else {
91 if (offset == 0) {
92 reiserfs_error(s, "vs-4020", "bitmap block %lu(%u) "
93 "can't be freed or reused",
94 block, bmap_count);
95 return 0;
96 }
97 }
98
99 if (bmap >= bmap_count) {
100 reiserfs_error(s, "vs-4030", "bitmap for requested block "
101 "is out of range: block=%lu, bitmap_nr=%u",
102 block, bmap);
103 return 0;
104 }
105
106 if (bit_value == 0 && block == SB_ROOT_BLOCK(s)) {
107 reiserfs_error(s, "vs-4050", "this is root block (%u), "
108 "it must be busy", SB_ROOT_BLOCK(s));
109 return 0;
110 }
111
112 return 1;
113}
114
115/*
116 * Searches in journal structures for a given block number (bmap, off).
117 * If block is found in reiserfs journal it suggests next free block
118 * candidate to test.
119 */
120static inline int is_block_in_journal(struct super_block *s, unsigned int bmap,
121 int off, int *next)
122{
123 b_blocknr_t tmp;
124
125 if (reiserfs_in_journal(s, bmap, off, 1, &tmp)) {
126 if (tmp) { /* hint supplied */
127 *next = tmp;
128 PROC_INFO_INC(s, scan_bitmap.in_journal_hint);
129 } else {
130 (*next) = off + 1; /* inc offset to avoid looping. */
131 PROC_INFO_INC(s, scan_bitmap.in_journal_nohint);
132 }
133 PROC_INFO_INC(s, scan_bitmap.retry);
134 return 1;
135 }
136 return 0;
137}
138
139/*
140 * Searches for a window of zero bits with given minimum and maximum
141 * lengths in one bitmap block
142 */
143static int scan_bitmap_block(struct reiserfs_transaction_handle *th,
144 unsigned int bmap_n, int *beg, int boundary,
145 int min, int max, int unfm)
146{
147 struct super_block *s = th->t_super;
148 struct reiserfs_bitmap_info *bi = &SB_AP_BITMAP(s)[bmap_n];
149 struct buffer_head *bh;
150 int end, next;
151 int org = *beg;
152
153 BUG_ON(!th->t_trans_id);
154 RFALSE(bmap_n >= reiserfs_bmap_count(s), "Bitmap %u is out of "
155 "range (0..%u)", bmap_n, reiserfs_bmap_count(s) - 1);
156 PROC_INFO_INC(s, scan_bitmap.bmap);
157
158 if (!bi) {
159 reiserfs_error(s, "jdm-4055", "NULL bitmap info pointer "
160 "for bitmap %d", bmap_n);
161 return 0;
162 }
163
164 bh = reiserfs_read_bitmap_block(s, bmap_n);
165 if (bh == NULL)
166 return 0;
167
168 while (1) {
169cont:
170 if (bi->free_count < min) {
171 brelse(bh);
172 return 0; /* No free blocks in this bitmap */
173 }
174
175 /* search for a first zero bit -- beginning of a window */
176 *beg = reiserfs_find_next_zero_le_bit
177 ((unsigned long *)(bh->b_data), boundary, *beg);
178
179 /*
180 * search for a zero bit fails or the rest of bitmap block
181 * cannot contain a zero window of minimum size
182 */
183 if (*beg + min > boundary) {
184 brelse(bh);
185 return 0;
186 }
187
188 if (unfm && is_block_in_journal(s, bmap_n, *beg, beg))
189 continue;
190 /* first zero bit found; we check next bits */
191 for (end = *beg + 1;; end++) {
192 if (end >= *beg + max || end >= boundary
193 || reiserfs_test_le_bit(end, bh->b_data)) {
194 next = end;
195 break;
196 }
197
198 /*
199 * finding the other end of zero bit window requires
200 * looking into journal structures (in case of
201 * searching for free blocks for unformatted nodes)
202 */
203 if (unfm && is_block_in_journal(s, bmap_n, end, &next))
204 break;
205 }
206
207 /*
208 * now (*beg) points to beginning of zero bits window,
209 * (end) points to one bit after the window end
210 */
211
212 /* found window of proper size */
213 if (end - *beg >= min) {
214 int i;
215 reiserfs_prepare_for_journal(s, bh, 1);
216 /*
217 * try to set all blocks used checking are
218 * they still free
219 */
220 for (i = *beg; i < end; i++) {
221 /* Don't check in journal again. */
222 if (reiserfs_test_and_set_le_bit
223 (i, bh->b_data)) {
224 /*
225 * bit was set by another process while
226 * we slept in prepare_for_journal()
227 */
228 PROC_INFO_INC(s, scan_bitmap.stolen);
229
230 /*
231 * we can continue with smaller set
232 * of allocated blocks, if length of
233 * this set is more or equal to `min'
234 */
235 if (i >= *beg + min) {
236 end = i;
237 break;
238 }
239
240 /*
241 * otherwise we clear all bit
242 * were set ...
243 */
244 while (--i >= *beg)
245 reiserfs_clear_le_bit
246 (i, bh->b_data);
247 reiserfs_restore_prepared_buffer(s, bh);
248 *beg = org;
249
250 /*
251 * Search again in current block
252 * from beginning
253 */
254 goto cont;
255 }
256 }
257 bi->free_count -= (end - *beg);
258 journal_mark_dirty(th, bh);
259 brelse(bh);
260
261 /* free block count calculation */
262 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s),
263 1);
264 PUT_SB_FREE_BLOCKS(s, SB_FREE_BLOCKS(s) - (end - *beg));
265 journal_mark_dirty(th, SB_BUFFER_WITH_SB(s));
266
267 return end - (*beg);
268 } else {
269 *beg = next;
270 }
271 }
272}
273
274static int bmap_hash_id(struct super_block *s, u32 id)
275{
276 char *hash_in = NULL;
277 unsigned long hash;
278 unsigned bm;
279
280 if (id <= 2) {
281 bm = 1;
282 } else {
283 hash_in = (char *)(&id);
284 hash = keyed_hash(hash_in, 4);
285 bm = hash % reiserfs_bmap_count(s);
286 if (!bm)
287 bm = 1;
288 }
289 /* this can only be true when SB_BMAP_NR = 1 */
290 if (bm >= reiserfs_bmap_count(s))
291 bm = 0;
292 return bm;
293}
294
295/*
296 * hashes the id and then returns > 0 if the block group for the
297 * corresponding hash is full
298 */
299static inline int block_group_used(struct super_block *s, u32 id)
300{
301 int bm = bmap_hash_id(s, id);
302 struct reiserfs_bitmap_info *info = &SB_AP_BITMAP(s)[bm];
303
304 /*
305 * If we don't have cached information on this bitmap block, we're
306 * going to have to load it later anyway. Loading it here allows us
307 * to make a better decision. This favors long-term performance gain
308 * with a better on-disk layout vs. a short term gain of skipping the
309 * read and potentially having a bad placement.
310 */
311 if (info->free_count == UINT_MAX) {
312 struct buffer_head *bh = reiserfs_read_bitmap_block(s, bm);
313 brelse(bh);
314 }
315
316 if (info->free_count > ((s->s_blocksize << 3) * 60 / 100)) {
317 return 0;
318 }
319 return 1;
320}
321
322/*
323 * the packing is returned in disk byte order
324 */
325__le32 reiserfs_choose_packing(struct inode * dir)
326{
327 __le32 packing;
328 if (TEST_OPTION(packing_groups, dir->i_sb)) {
329 u32 parent_dir = le32_to_cpu(INODE_PKEY(dir)->k_dir_id);
330 /*
331 * some versions of reiserfsck expect packing locality 1 to be
332 * special
333 */
334 if (parent_dir == 1 || block_group_used(dir->i_sb, parent_dir))
335 packing = INODE_PKEY(dir)->k_objectid;
336 else
337 packing = INODE_PKEY(dir)->k_dir_id;
338 } else
339 packing = INODE_PKEY(dir)->k_objectid;
340 return packing;
341}
342
343/*
344 * Tries to find contiguous zero bit window (given size) in given region of
345 * bitmap and place new blocks there. Returns number of allocated blocks.
346 */
347static int scan_bitmap(struct reiserfs_transaction_handle *th,
348 b_blocknr_t * start, b_blocknr_t finish,
349 int min, int max, int unfm, sector_t file_block)
350{
351 int nr_allocated = 0;
352 struct super_block *s = th->t_super;
353 unsigned int bm, off;
354 unsigned int end_bm, end_off;
355 unsigned int off_max = s->s_blocksize << 3;
356
357 BUG_ON(!th->t_trans_id);
358 PROC_INFO_INC(s, scan_bitmap.call);
359
360 /* No point in looking for more free blocks */
361 if (SB_FREE_BLOCKS(s) <= 0)
362 return 0;
363
364 get_bit_address(s, *start, &bm, &off);
365 get_bit_address(s, finish, &end_bm, &end_off);
366 if (bm > reiserfs_bmap_count(s))
367 return 0;
368 if (end_bm > reiserfs_bmap_count(s))
369 end_bm = reiserfs_bmap_count(s);
370
371 /*
372 * When the bitmap is more than 10% free, anyone can allocate.
373 * When it's less than 10% free, only files that already use the
374 * bitmap are allowed. Once we pass 80% full, this restriction
375 * is lifted.
376 *
377 * We do this so that files that grow later still have space close to
378 * their original allocation. This improves locality, and presumably
379 * performance as a result.
380 *
381 * This is only an allocation policy and does not make up for getting a
382 * bad hint. Decent hinting must be implemented for this to work well.
383 */
384 if (TEST_OPTION(skip_busy, s)
385 && SB_FREE_BLOCKS(s) > SB_BLOCK_COUNT(s) / 20) {
386 for (; bm < end_bm; bm++, off = 0) {
387 if ((off && (!unfm || (file_block != 0)))
388 || SB_AP_BITMAP(s)[bm].free_count >
389 (s->s_blocksize << 3) / 10)
390 nr_allocated =
391 scan_bitmap_block(th, bm, &off, off_max,
392 min, max, unfm);
393 if (nr_allocated)
394 goto ret;
395 }
396 /* we know from above that start is a reasonable number */
397 get_bit_address(s, *start, &bm, &off);
398 }
399
400 for (; bm < end_bm; bm++, off = 0) {
401 nr_allocated =
402 scan_bitmap_block(th, bm, &off, off_max, min, max, unfm);
403 if (nr_allocated)
404 goto ret;
405 }
406
407 nr_allocated =
408 scan_bitmap_block(th, bm, &off, end_off + 1, min, max, unfm);
409
410ret:
411 *start = bm * off_max + off;
412 return nr_allocated;
413
414}
415
416static void _reiserfs_free_block(struct reiserfs_transaction_handle *th,
417 struct inode *inode, b_blocknr_t block,
418 int for_unformatted)
419{
420 struct super_block *s = th->t_super;
421 struct reiserfs_super_block *rs;
422 struct buffer_head *sbh, *bmbh;
423 struct reiserfs_bitmap_info *apbi;
424 unsigned int nr, offset;
425
426 BUG_ON(!th->t_trans_id);
427 PROC_INFO_INC(s, free_block);
428 rs = SB_DISK_SUPER_BLOCK(s);
429 sbh = SB_BUFFER_WITH_SB(s);
430 apbi = SB_AP_BITMAP(s);
431
432 get_bit_address(s, block, &nr, &offset);
433
434 if (nr >= reiserfs_bmap_count(s)) {
435 reiserfs_error(s, "vs-4075", "block %lu is out of range",
436 block);
437 return;
438 }
439
440 bmbh = reiserfs_read_bitmap_block(s, nr);
441 if (!bmbh)
442 return;
443
444 reiserfs_prepare_for_journal(s, bmbh, 1);
445
446 /* clear bit for the given block in bit map */
447 if (!reiserfs_test_and_clear_le_bit(offset, bmbh->b_data)) {
448 reiserfs_error(s, "vs-4080",
449 "block %lu: bit already cleared", block);
450 }
451 apbi[nr].free_count++;
452 journal_mark_dirty(th, bmbh);
453 brelse(bmbh);
454
455 reiserfs_prepare_for_journal(s, sbh, 1);
456 /* update super block */
457 set_sb_free_blocks(rs, sb_free_blocks(rs) + 1);
458
459 journal_mark_dirty(th, sbh);
460 if (for_unformatted) {
461 int depth = reiserfs_write_unlock_nested(s);
462 dquot_free_block_nodirty(inode, 1);
463 reiserfs_write_lock_nested(s, depth);
464 }
465}
466
467void reiserfs_free_block(struct reiserfs_transaction_handle *th,
468 struct inode *inode, b_blocknr_t block,
469 int for_unformatted)
470{
471 struct super_block *s = th->t_super;
472
473 BUG_ON(!th->t_trans_id);
474 RFALSE(!s, "vs-4061: trying to free block on nonexistent device");
475 if (!is_reusable(s, block, 1))
476 return;
477
478 if (block > sb_block_count(REISERFS_SB(s)->s_rs)) {
479 reiserfs_error(th->t_super, "bitmap-4072",
480 "Trying to free block outside file system "
481 "boundaries (%lu > %lu)",
482 block, sb_block_count(REISERFS_SB(s)->s_rs));
483 return;
484 }
485 /* mark it before we clear it, just in case */
486 journal_mark_freed(th, s, block);
487 _reiserfs_free_block(th, inode, block, for_unformatted);
488}
489
490/* preallocated blocks don't need to be run through journal_mark_freed */
491static void reiserfs_free_prealloc_block(struct reiserfs_transaction_handle *th,
492 struct inode *inode, b_blocknr_t block)
493{
494 BUG_ON(!th->t_trans_id);
495 RFALSE(!th->t_super,
496 "vs-4060: trying to free block on nonexistent device");
497 if (!is_reusable(th->t_super, block, 1))
498 return;
499 _reiserfs_free_block(th, inode, block, 1);
500}
501
502static void __discard_prealloc(struct reiserfs_transaction_handle *th,
503 struct reiserfs_inode_info *ei)
504{
505 unsigned long save = ei->i_prealloc_block;
506 int dirty = 0;
507 struct inode *inode = &ei->vfs_inode;
508
509 BUG_ON(!th->t_trans_id);
510#ifdef CONFIG_REISERFS_CHECK
511 if (ei->i_prealloc_count < 0)
512 reiserfs_error(th->t_super, "zam-4001",
513 "inode has negative prealloc blocks count.");
514#endif
515 while (ei->i_prealloc_count > 0) {
516 b_blocknr_t block_to_free;
517
518 /*
519 * reiserfs_free_prealloc_block can drop the write lock,
520 * which could allow another caller to free the same block.
521 * We can protect against it by modifying the prealloc
522 * state before calling it.
523 */
524 block_to_free = ei->i_prealloc_block++;
525 ei->i_prealloc_count--;
526 reiserfs_free_prealloc_block(th, inode, block_to_free);
527 dirty = 1;
528 }
529 if (dirty)
530 reiserfs_update_sd(th, inode);
531 ei->i_prealloc_block = save;
532 list_del_init(&ei->i_prealloc_list);
533}
534
535/* FIXME: It should be inline function */
536void reiserfs_discard_prealloc(struct reiserfs_transaction_handle *th,
537 struct inode *inode)
538{
539 struct reiserfs_inode_info *ei = REISERFS_I(inode);
540
541 BUG_ON(!th->t_trans_id);
542 if (ei->i_prealloc_count)
543 __discard_prealloc(th, ei);
544}
545
546void reiserfs_discard_all_prealloc(struct reiserfs_transaction_handle *th)
547{
548 struct list_head *plist = &SB_JOURNAL(th->t_super)->j_prealloc_list;
549
550 BUG_ON(!th->t_trans_id);
551 while (!list_empty(plist)) {
552 struct reiserfs_inode_info *ei;
553 ei = list_entry(plist->next, struct reiserfs_inode_info,
554 i_prealloc_list);
555#ifdef CONFIG_REISERFS_CHECK
556 if (!ei->i_prealloc_count) {
557 reiserfs_error(th->t_super, "zam-4001",
558 "inode is in prealloc list but has "
559 "no preallocated blocks.");
560 }
561#endif
562 __discard_prealloc(th, ei);
563 }
564}
565
566void reiserfs_init_alloc_options(struct super_block *s)
567{
568 set_bit(_ALLOC_skip_busy, &SB_ALLOC_OPTS(s));
569 set_bit(_ALLOC_dirid_groups, &SB_ALLOC_OPTS(s));
570 set_bit(_ALLOC_packing_groups, &SB_ALLOC_OPTS(s));
571}
572
573/* block allocator related options are parsed here */
574int reiserfs_parse_alloc_options(struct super_block *s, char *options)
575{
576 char *this_char, *value;
577
578 /* clear default settings */
579 REISERFS_SB(s)->s_alloc_options.bits = 0;
580
581 while ((this_char = strsep(&options, ":")) != NULL) {
582 if ((value = strchr(this_char, '=')) != NULL)
583 *value++ = 0;
584
585 if (!strcmp(this_char, "concentrating_formatted_nodes")) {
586 int temp;
587 SET_OPTION(concentrating_formatted_nodes);
588 temp = (value
589 && *value) ? simple_strtoul(value, &value,
590 0) : 10;
591 if (temp <= 0 || temp > 100) {
592 REISERFS_SB(s)->s_alloc_options.border = 10;
593 } else {
594 REISERFS_SB(s)->s_alloc_options.border =
595 100 / temp;
596 }
597 continue;
598 }
599 if (!strcmp(this_char, "displacing_large_files")) {
600 SET_OPTION(displacing_large_files);
601 REISERFS_SB(s)->s_alloc_options.large_file_size =
602 (value
603 && *value) ? simple_strtoul(value, &value, 0) : 16;
604 continue;
605 }
606 if (!strcmp(this_char, "displacing_new_packing_localities")) {
607 SET_OPTION(displacing_new_packing_localities);
608 continue;
609 }
610
611 if (!strcmp(this_char, "old_hashed_relocation")) {
612 SET_OPTION(old_hashed_relocation);
613 continue;
614 }
615
616 if (!strcmp(this_char, "new_hashed_relocation")) {
617 SET_OPTION(new_hashed_relocation);
618 continue;
619 }
620
621 if (!strcmp(this_char, "dirid_groups")) {
622 SET_OPTION(dirid_groups);
623 continue;
624 }
625 if (!strcmp(this_char, "oid_groups")) {
626 SET_OPTION(oid_groups);
627 continue;
628 }
629 if (!strcmp(this_char, "packing_groups")) {
630 SET_OPTION(packing_groups);
631 continue;
632 }
633 if (!strcmp(this_char, "hashed_formatted_nodes")) {
634 SET_OPTION(hashed_formatted_nodes);
635 continue;
636 }
637
638 if (!strcmp(this_char, "skip_busy")) {
639 SET_OPTION(skip_busy);
640 continue;
641 }
642
643 if (!strcmp(this_char, "hundredth_slices")) {
644 SET_OPTION(hundredth_slices);
645 continue;
646 }
647
648 if (!strcmp(this_char, "old_way")) {
649 SET_OPTION(old_way);
650 continue;
651 }
652
653 if (!strcmp(this_char, "displace_based_on_dirid")) {
654 SET_OPTION(displace_based_on_dirid);
655 continue;
656 }
657
658 if (!strcmp(this_char, "preallocmin")) {
659 REISERFS_SB(s)->s_alloc_options.preallocmin =
660 (value
661 && *value) ? simple_strtoul(value, &value, 0) : 4;
662 continue;
663 }
664
665 if (!strcmp(this_char, "preallocsize")) {
666 REISERFS_SB(s)->s_alloc_options.preallocsize =
667 (value
668 && *value) ? simple_strtoul(value, &value,
669 0) :
670 PREALLOCATION_SIZE;
671 continue;
672 }
673
674 reiserfs_warning(s, "zam-4001", "unknown option - %s",
675 this_char);
676 return 1;
677 }
678
679 reiserfs_info(s, "allocator options = [%08x]\n", SB_ALLOC_OPTS(s));
680 return 0;
681}
682
683static void print_sep(struct seq_file *seq, int *first)
684{
685 if (!*first)
686 seq_puts(seq, ":");
687 else
688 *first = 0;
689}
690
691void show_alloc_options(struct seq_file *seq, struct super_block *s)
692{
693 int first = 1;
694
695 if (SB_ALLOC_OPTS(s) == ((1 << _ALLOC_skip_busy) |
696 (1 << _ALLOC_dirid_groups) | (1 << _ALLOC_packing_groups)))
697 return;
698
699 seq_puts(seq, ",alloc=");
700
701 if (TEST_OPTION(concentrating_formatted_nodes, s)) {
702 print_sep(seq, &first);
703 if (REISERFS_SB(s)->s_alloc_options.border != 10) {
704 seq_printf(seq, "concentrating_formatted_nodes=%d",
705 100 / REISERFS_SB(s)->s_alloc_options.border);
706 } else
707 seq_puts(seq, "concentrating_formatted_nodes");
708 }
709 if (TEST_OPTION(displacing_large_files, s)) {
710 print_sep(seq, &first);
711 if (REISERFS_SB(s)->s_alloc_options.large_file_size != 16) {
712 seq_printf(seq, "displacing_large_files=%lu",
713 REISERFS_SB(s)->s_alloc_options.large_file_size);
714 } else
715 seq_puts(seq, "displacing_large_files");
716 }
717 if (TEST_OPTION(displacing_new_packing_localities, s)) {
718 print_sep(seq, &first);
719 seq_puts(seq, "displacing_new_packing_localities");
720 }
721 if (TEST_OPTION(old_hashed_relocation, s)) {
722 print_sep(seq, &first);
723 seq_puts(seq, "old_hashed_relocation");
724 }
725 if (TEST_OPTION(new_hashed_relocation, s)) {
726 print_sep(seq, &first);
727 seq_puts(seq, "new_hashed_relocation");
728 }
729 if (TEST_OPTION(dirid_groups, s)) {
730 print_sep(seq, &first);
731 seq_puts(seq, "dirid_groups");
732 }
733 if (TEST_OPTION(oid_groups, s)) {
734 print_sep(seq, &first);
735 seq_puts(seq, "oid_groups");
736 }
737 if (TEST_OPTION(packing_groups, s)) {
738 print_sep(seq, &first);
739 seq_puts(seq, "packing_groups");
740 }
741 if (TEST_OPTION(hashed_formatted_nodes, s)) {
742 print_sep(seq, &first);
743 seq_puts(seq, "hashed_formatted_nodes");
744 }
745 if (TEST_OPTION(skip_busy, s)) {
746 print_sep(seq, &first);
747 seq_puts(seq, "skip_busy");
748 }
749 if (TEST_OPTION(hundredth_slices, s)) {
750 print_sep(seq, &first);
751 seq_puts(seq, "hundredth_slices");
752 }
753 if (TEST_OPTION(old_way, s)) {
754 print_sep(seq, &first);
755 seq_puts(seq, "old_way");
756 }
757 if (TEST_OPTION(displace_based_on_dirid, s)) {
758 print_sep(seq, &first);
759 seq_puts(seq, "displace_based_on_dirid");
760 }
761 if (REISERFS_SB(s)->s_alloc_options.preallocmin != 0) {
762 print_sep(seq, &first);
763 seq_printf(seq, "preallocmin=%d",
764 REISERFS_SB(s)->s_alloc_options.preallocmin);
765 }
766 if (REISERFS_SB(s)->s_alloc_options.preallocsize != 17) {
767 print_sep(seq, &first);
768 seq_printf(seq, "preallocsize=%d",
769 REISERFS_SB(s)->s_alloc_options.preallocsize);
770 }
771}
772
773static inline void new_hashed_relocation(reiserfs_blocknr_hint_t * hint)
774{
775 char *hash_in;
776
777 if (hint->formatted_node) {
778 hash_in = (char *)&hint->key.k_dir_id;
779 } else {
780 if (!hint->inode) {
781 /*hint->search_start = hint->beg;*/
782 hash_in = (char *)&hint->key.k_dir_id;
783 } else
784 if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
785 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
786 else
787 hash_in =
788 (char *)(&INODE_PKEY(hint->inode)->k_objectid);
789 }
790
791 hint->search_start =
792 hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
793}
794
795/*
796 * Relocation based on dirid, hashing them into a given bitmap block
797 * files. Formatted nodes are unaffected, a separate policy covers them
798 */
799static void dirid_groups(reiserfs_blocknr_hint_t * hint)
800{
801 unsigned long hash;
802 __u32 dirid = 0;
803 int bm = 0;
804 struct super_block *sb = hint->th->t_super;
805
806 if (hint->inode)
807 dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
808 else if (hint->formatted_node)
809 dirid = hint->key.k_dir_id;
810
811 if (dirid) {
812 bm = bmap_hash_id(sb, dirid);
813 hash = bm * (sb->s_blocksize << 3);
814 /* give a portion of the block group to metadata */
815 if (hint->inode)
816 hash += sb->s_blocksize / 2;
817 hint->search_start = hash;
818 }
819}
820
821/*
822 * Relocation based on oid, hashing them into a given bitmap block
823 * files. Formatted nodes are unaffected, a separate policy covers them
824 */
825static void oid_groups(reiserfs_blocknr_hint_t * hint)
826{
827 if (hint->inode) {
828 unsigned long hash;
829 __u32 oid;
830 __u32 dirid;
831 int bm;
832
833 dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
834
835 /*
836 * keep the root dir and it's first set of subdirs close to
837 * the start of the disk
838 */
839 if (dirid <= 2)
840 hash = (hint->inode->i_sb->s_blocksize << 3);
841 else {
842 oid = le32_to_cpu(INODE_PKEY(hint->inode)->k_objectid);
843 bm = bmap_hash_id(hint->inode->i_sb, oid);
844 hash = bm * (hint->inode->i_sb->s_blocksize << 3);
845 }
846 hint->search_start = hash;
847 }
848}
849
850/*
851 * returns 1 if it finds an indirect item and gets valid hint info
852 * from it, otherwise 0
853 */
854static int get_left_neighbor(reiserfs_blocknr_hint_t * hint)
855{
856 struct treepath *path;
857 struct buffer_head *bh;
858 struct item_head *ih;
859 int pos_in_item;
860 __le32 *item;
861 int ret = 0;
862
863 /*
864 * reiserfs code can call this function w/o pointer to path
865 * structure supplied; then we rely on supplied search_start
866 */
867 if (!hint->path)
868 return 0;
869
870 path = hint->path;
871 bh = get_last_bh(path);
872 RFALSE(!bh, "green-4002: Illegal path specified to get_left_neighbor");
873 ih = tp_item_head(path);
874 pos_in_item = path->pos_in_item;
875 item = tp_item_body(path);
876
877 hint->search_start = bh->b_blocknr;
878
879 /*
880 * for indirect item: go to left and look for the first non-hole entry
881 * in the indirect item
882 */
883 if (!hint->formatted_node && is_indirect_le_ih(ih)) {
884 if (pos_in_item == I_UNFM_NUM(ih))
885 pos_in_item--;
886 while (pos_in_item >= 0) {
887 int t = get_block_num(item, pos_in_item);
888 if (t) {
889 hint->search_start = t;
890 ret = 1;
891 break;
892 }
893 pos_in_item--;
894 }
895 }
896
897 /* does result value fit into specified region? */
898 return ret;
899}
900
901/*
902 * should be, if formatted node, then try to put on first part of the device
903 * specified as number of percent with mount option device, else try to put
904 * on last of device. This is not to say it is good code to do so,
905 * but the effect should be measured.
906 */
907static inline void set_border_in_hint(struct super_block *s,
908 reiserfs_blocknr_hint_t * hint)
909{
910 b_blocknr_t border =
911 SB_BLOCK_COUNT(s) / REISERFS_SB(s)->s_alloc_options.border;
912
913 if (hint->formatted_node)
914 hint->end = border - 1;
915 else
916 hint->beg = border;
917}
918
919static inline void displace_large_file(reiserfs_blocknr_hint_t * hint)
920{
921 if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
922 hint->search_start =
923 hint->beg +
924 keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_dir_id),
925 4) % (hint->end - hint->beg);
926 else
927 hint->search_start =
928 hint->beg +
929 keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_objectid),
930 4) % (hint->end - hint->beg);
931}
932
933static inline void hash_formatted_node(reiserfs_blocknr_hint_t * hint)
934{
935 char *hash_in;
936
937 if (!hint->inode)
938 hash_in = (char *)&hint->key.k_dir_id;
939 else if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
940 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
941 else
942 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_objectid);
943
944 hint->search_start =
945 hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
946}
947
948static inline int
949this_blocknr_allocation_would_make_it_a_large_file(reiserfs_blocknr_hint_t *
950 hint)
951{
952 return hint->block ==
953 REISERFS_SB(hint->th->t_super)->s_alloc_options.large_file_size;
954}
955
956#ifdef DISPLACE_NEW_PACKING_LOCALITIES
957static inline void displace_new_packing_locality(reiserfs_blocknr_hint_t * hint)
958{
959 struct in_core_key *key = &hint->key;
960
961 hint->th->displace_new_blocks = 0;
962 hint->search_start =
963 hint->beg + keyed_hash((char *)(&key->k_objectid),
964 4) % (hint->end - hint->beg);
965}
966#endif
967
968static inline int old_hashed_relocation(reiserfs_blocknr_hint_t * hint)
969{
970 b_blocknr_t border;
971 u32 hash_in;
972
973 if (hint->formatted_node || hint->inode == NULL) {
974 return 0;
975 }
976
977 hash_in = le32_to_cpu((INODE_PKEY(hint->inode))->k_dir_id);
978 border =
979 hint->beg + (u32) keyed_hash(((char *)(&hash_in)),
980 4) % (hint->end - hint->beg - 1);
981 if (border > hint->search_start)
982 hint->search_start = border;
983
984 return 1;
985}
986
987static inline int old_way(reiserfs_blocknr_hint_t * hint)
988{
989 b_blocknr_t border;
990
991 if (hint->formatted_node || hint->inode == NULL) {
992 return 0;
993 }
994
995 border =
996 hint->beg +
997 le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id) % (hint->end -
998 hint->beg);
999 if (border > hint->search_start)
1000 hint->search_start = border;
1001
1002 return 1;
1003}
1004
1005static inline void hundredth_slices(reiserfs_blocknr_hint_t * hint)
1006{
1007 struct in_core_key *key = &hint->key;
1008 b_blocknr_t slice_start;
1009
1010 slice_start =
1011 (keyed_hash((char *)(&key->k_dir_id), 4) % 100) * (hint->end / 100);
1012 if (slice_start > hint->search_start
1013 || slice_start + (hint->end / 100) <= hint->search_start) {
1014 hint->search_start = slice_start;
1015 }
1016}
1017
1018static void determine_search_start(reiserfs_blocknr_hint_t * hint,
1019 int amount_needed)
1020{
1021 struct super_block *s = hint->th->t_super;
1022 int unfm_hint;
1023
1024 hint->beg = 0;
1025 hint->end = SB_BLOCK_COUNT(s) - 1;
1026
1027 /* This is former border algorithm. Now with tunable border offset */
1028 if (concentrating_formatted_nodes(s))
1029 set_border_in_hint(s, hint);
1030
1031#ifdef DISPLACE_NEW_PACKING_LOCALITIES
1032 /*
1033 * whenever we create a new directory, we displace it. At first
1034 * we will hash for location, later we might look for a moderately
1035 * empty place for it
1036 */
1037 if (displacing_new_packing_localities(s)
1038 && hint->th->displace_new_blocks) {
1039 displace_new_packing_locality(hint);
1040
1041 /*
1042 * we do not continue determine_search_start,
1043 * if new packing locality is being displaced
1044 */
1045 return;
1046 }
1047#endif
1048
1049 /*
1050 * all persons should feel encouraged to add more special cases
1051 * here and test them
1052 */
1053
1054 if (displacing_large_files(s) && !hint->formatted_node
1055 && this_blocknr_allocation_would_make_it_a_large_file(hint)) {
1056 displace_large_file(hint);
1057 return;
1058 }
1059
1060 /*
1061 * if none of our special cases is relevant, use the left
1062 * neighbor in the tree order of the new node we are allocating for
1063 */
1064 if (hint->formatted_node && TEST_OPTION(hashed_formatted_nodes, s)) {
1065 hash_formatted_node(hint);
1066 return;
1067 }
1068
1069 unfm_hint = get_left_neighbor(hint);
1070
1071 /*
1072 * Mimic old block allocator behaviour, that is if VFS allowed for
1073 * preallocation, new blocks are displaced based on directory ID.
1074 * Also, if suggested search_start is less than last preallocated
1075 * block, we start searching from it, assuming that HDD dataflow
1076 * is faster in forward direction
1077 */
1078 if (TEST_OPTION(old_way, s)) {
1079 if (!hint->formatted_node) {
1080 if (!reiserfs_hashed_relocation(s))
1081 old_way(hint);
1082 else if (!reiserfs_no_unhashed_relocation(s))
1083 old_hashed_relocation(hint);
1084
1085 if (hint->inode
1086 && hint->search_start <
1087 REISERFS_I(hint->inode)->i_prealloc_block)
1088 hint->search_start =
1089 REISERFS_I(hint->inode)->i_prealloc_block;
1090 }
1091 return;
1092 }
1093
1094 /* This is an approach proposed by Hans */
1095 if (TEST_OPTION(hundredth_slices, s)
1096 && !(displacing_large_files(s) && !hint->formatted_node)) {
1097 hundredth_slices(hint);
1098 return;
1099 }
1100
1101 /* old_hashed_relocation only works on unformatted */
1102 if (!unfm_hint && !hint->formatted_node &&
1103 TEST_OPTION(old_hashed_relocation, s)) {
1104 old_hashed_relocation(hint);
1105 }
1106
1107 /* new_hashed_relocation works with both formatted/unformatted nodes */
1108 if ((!unfm_hint || hint->formatted_node) &&
1109 TEST_OPTION(new_hashed_relocation, s)) {
1110 new_hashed_relocation(hint);
1111 }
1112
1113 /* dirid grouping works only on unformatted nodes */
1114 if (!unfm_hint && !hint->formatted_node && TEST_OPTION(dirid_groups, s)) {
1115 dirid_groups(hint);
1116 }
1117#ifdef DISPLACE_NEW_PACKING_LOCALITIES
1118 if (hint->formatted_node && TEST_OPTION(dirid_groups, s)) {
1119 dirid_groups(hint);
1120 }
1121#endif
1122
1123 /* oid grouping works only on unformatted nodes */
1124 if (!unfm_hint && !hint->formatted_node && TEST_OPTION(oid_groups, s)) {
1125 oid_groups(hint);
1126 }
1127 return;
1128}
1129
1130static int determine_prealloc_size(reiserfs_blocknr_hint_t * hint)
1131{
1132 /* make minimum size a mount option and benchmark both ways */
1133 /* we preallocate blocks only for regular files, specific size */
1134 /* benchmark preallocating always and see what happens */
1135
1136 hint->prealloc_size = 0;
1137
1138 if (!hint->formatted_node && hint->preallocate) {
1139 if (S_ISREG(hint->inode->i_mode) && !IS_PRIVATE(hint->inode)
1140 && hint->inode->i_size >=
1141 REISERFS_SB(hint->th->t_super)->s_alloc_options.
1142 preallocmin * hint->inode->i_sb->s_blocksize)
1143 hint->prealloc_size =
1144 REISERFS_SB(hint->th->t_super)->s_alloc_options.
1145 preallocsize - 1;
1146 }
1147 return CARRY_ON;
1148}
1149
1150static inline int allocate_without_wrapping_disk(reiserfs_blocknr_hint_t * hint,
1151 b_blocknr_t * new_blocknrs,
1152 b_blocknr_t start,
1153 b_blocknr_t finish, int min,
1154 int amount_needed,
1155 int prealloc_size)
1156{
1157 int rest = amount_needed;
1158 int nr_allocated;
1159
1160 while (rest > 0 && start <= finish) {
1161 nr_allocated = scan_bitmap(hint->th, &start, finish, min,
1162 rest + prealloc_size,
1163 !hint->formatted_node, hint->block);
1164
1165 if (nr_allocated == 0) /* no new blocks allocated, return */
1166 break;
1167
1168 /* fill free_blocknrs array first */
1169 while (rest > 0 && nr_allocated > 0) {
1170 *new_blocknrs++ = start++;
1171 rest--;
1172 nr_allocated--;
1173 }
1174
1175 /* do we have something to fill prealloc. array also ? */
1176 if (nr_allocated > 0) {
1177 /*
1178 * it means prealloc_size was greater that 0 and
1179 * we do preallocation
1180 */
1181 list_add(&REISERFS_I(hint->inode)->i_prealloc_list,
1182 &SB_JOURNAL(hint->th->t_super)->
1183 j_prealloc_list);
1184 REISERFS_I(hint->inode)->i_prealloc_block = start;
1185 REISERFS_I(hint->inode)->i_prealloc_count =
1186 nr_allocated;
1187 break;
1188 }
1189 }
1190
1191 return (amount_needed - rest);
1192}
1193
1194static inline int blocknrs_and_prealloc_arrays_from_search_start
1195 (reiserfs_blocknr_hint_t * hint, b_blocknr_t * new_blocknrs,
1196 int amount_needed) {
1197 struct super_block *s = hint->th->t_super;
1198 b_blocknr_t start = hint->search_start;
1199 b_blocknr_t finish = SB_BLOCK_COUNT(s) - 1;
1200 int passno = 0;
1201 int nr_allocated = 0;
1202 int depth;
1203
1204 determine_prealloc_size(hint);
1205 if (!hint->formatted_node) {
1206 int quota_ret;
1207#ifdef REISERQUOTA_DEBUG
1208 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1209 "reiserquota: allocating %d blocks id=%u",
1210 amount_needed, hint->inode->i_uid);
1211#endif
1212 depth = reiserfs_write_unlock_nested(s);
1213 quota_ret =
1214 dquot_alloc_block_nodirty(hint->inode, amount_needed);
1215 if (quota_ret) { /* Quota exceeded? */
1216 reiserfs_write_lock_nested(s, depth);
1217 return QUOTA_EXCEEDED;
1218 }
1219 if (hint->preallocate && hint->prealloc_size) {
1220#ifdef REISERQUOTA_DEBUG
1221 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1222 "reiserquota: allocating (prealloc) %d blocks id=%u",
1223 hint->prealloc_size, hint->inode->i_uid);
1224#endif
1225 quota_ret = dquot_prealloc_block_nodirty(hint->inode,
1226 hint->prealloc_size);
1227 if (quota_ret)
1228 hint->preallocate = hint->prealloc_size = 0;
1229 }
1230 /* for unformatted nodes, force large allocations */
1231 reiserfs_write_lock_nested(s, depth);
1232 }
1233
1234 do {
1235 switch (passno++) {
1236 case 0: /* Search from hint->search_start to end of disk */
1237 start = hint->search_start;
1238 finish = SB_BLOCK_COUNT(s) - 1;
1239 break;
1240 case 1: /* Search from hint->beg to hint->search_start */
1241 start = hint->beg;
1242 finish = hint->search_start;
1243 break;
1244 case 2: /* Last chance: Search from 0 to hint->beg */
1245 start = 0;
1246 finish = hint->beg;
1247 break;
1248 default:
1249 /* We've tried searching everywhere, not enough space */
1250 /* Free the blocks */
1251 if (!hint->formatted_node) {
1252#ifdef REISERQUOTA_DEBUG
1253 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1254 "reiserquota: freeing (nospace) %d blocks id=%u",
1255 amount_needed +
1256 hint->prealloc_size -
1257 nr_allocated,
1258 hint->inode->i_uid);
1259#endif
1260 /* Free not allocated blocks */
1261 depth = reiserfs_write_unlock_nested(s);
1262 dquot_free_block_nodirty(hint->inode,
1263 amount_needed + hint->prealloc_size -
1264 nr_allocated);
1265 reiserfs_write_lock_nested(s, depth);
1266 }
1267 while (nr_allocated--)
1268 reiserfs_free_block(hint->th, hint->inode,
1269 new_blocknrs[nr_allocated],
1270 !hint->formatted_node);
1271
1272 return NO_DISK_SPACE;
1273 }
1274 } while ((nr_allocated += allocate_without_wrapping_disk(hint,
1275 new_blocknrs +
1276 nr_allocated,
1277 start, finish,
1278 1,
1279 amount_needed -
1280 nr_allocated,
1281 hint->
1282 prealloc_size))
1283 < amount_needed);
1284 if (!hint->formatted_node &&
1285 amount_needed + hint->prealloc_size >
1286 nr_allocated + REISERFS_I(hint->inode)->i_prealloc_count) {
1287 /* Some of preallocation blocks were not allocated */
1288#ifdef REISERQUOTA_DEBUG
1289 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1290 "reiserquota: freeing (failed prealloc) %d blocks id=%u",
1291 amount_needed + hint->prealloc_size -
1292 nr_allocated -
1293 REISERFS_I(hint->inode)->i_prealloc_count,
1294 hint->inode->i_uid);
1295#endif
1296
1297 depth = reiserfs_write_unlock_nested(s);
1298 dquot_free_block_nodirty(hint->inode, amount_needed +
1299 hint->prealloc_size - nr_allocated -
1300 REISERFS_I(hint->inode)->
1301 i_prealloc_count);
1302 reiserfs_write_lock_nested(s, depth);
1303 }
1304
1305 return CARRY_ON;
1306}
1307
1308/* grab new blocknrs from preallocated list */
1309/* return amount still needed after using them */
1310static int use_preallocated_list_if_available(reiserfs_blocknr_hint_t * hint,
1311 b_blocknr_t * new_blocknrs,
1312 int amount_needed)
1313{
1314 struct inode *inode = hint->inode;
1315
1316 if (REISERFS_I(inode)->i_prealloc_count > 0) {
1317 while (amount_needed) {
1318
1319 *new_blocknrs++ = REISERFS_I(inode)->i_prealloc_block++;
1320 REISERFS_I(inode)->i_prealloc_count--;
1321
1322 amount_needed--;
1323
1324 if (REISERFS_I(inode)->i_prealloc_count <= 0) {
1325 list_del(&REISERFS_I(inode)->i_prealloc_list);
1326 break;
1327 }
1328 }
1329 }
1330 /* return amount still needed after using preallocated blocks */
1331 return amount_needed;
1332}
1333
1334int reiserfs_allocate_blocknrs(reiserfs_blocknr_hint_t *hint,
1335 b_blocknr_t *new_blocknrs,
1336 int amount_needed,
1337 /* Amount of blocks we have already reserved */
1338 int reserved_by_us)
1339{
1340 int initial_amount_needed = amount_needed;
1341 int ret;
1342 struct super_block *s = hint->th->t_super;
1343
1344 /* Check if there is enough space, taking into account reserved space */
1345 if (SB_FREE_BLOCKS(s) - REISERFS_SB(s)->reserved_blocks <
1346 amount_needed - reserved_by_us)
1347 return NO_DISK_SPACE;
1348 /* should this be if !hint->inode && hint->preallocate? */
1349 /* do you mean hint->formatted_node can be removed ? - Zam */
1350 /*
1351 * hint->formatted_node cannot be removed because we try to access
1352 * inode information here, and there is often no inode associated with
1353 * metadata allocations - green
1354 */
1355
1356 if (!hint->formatted_node && hint->preallocate) {
1357 amount_needed = use_preallocated_list_if_available
1358 (hint, new_blocknrs, amount_needed);
1359
1360 /*
1361 * We have all the block numbers we need from the
1362 * prealloc list
1363 */
1364 if (amount_needed == 0)
1365 return CARRY_ON;
1366 new_blocknrs += (initial_amount_needed - amount_needed);
1367 }
1368
1369 /* find search start and save it in hint structure */
1370 determine_search_start(hint, amount_needed);
1371 if (hint->search_start >= SB_BLOCK_COUNT(s))
1372 hint->search_start = SB_BLOCK_COUNT(s) - 1;
1373
1374 /* allocation itself; fill new_blocknrs and preallocation arrays */
1375 ret = blocknrs_and_prealloc_arrays_from_search_start
1376 (hint, new_blocknrs, amount_needed);
1377
1378 /*
1379 * We used prealloc. list to fill (partially) new_blocknrs array.
1380 * If final allocation fails we need to return blocks back to
1381 * prealloc. list or just free them. -- Zam (I chose second
1382 * variant)
1383 */
1384 if (ret != CARRY_ON) {
1385 while (amount_needed++ < initial_amount_needed) {
1386 reiserfs_free_block(hint->th, hint->inode,
1387 *(--new_blocknrs), 1);
1388 }
1389 }
1390 return ret;
1391}
1392
1393void reiserfs_cache_bitmap_metadata(struct super_block *sb,
1394 struct buffer_head *bh,
1395 struct reiserfs_bitmap_info *info)
1396{
1397 unsigned long *cur = (unsigned long *)(bh->b_data + bh->b_size);
1398
1399 /* The first bit must ALWAYS be 1 */
1400 if (!reiserfs_test_le_bit(0, (unsigned long *)bh->b_data))
1401 reiserfs_error(sb, "reiserfs-2025", "bitmap block %lu is "
1402 "corrupted: first bit must be 1", bh->b_blocknr);
1403
1404 info->free_count = 0;
1405
1406 while (--cur >= (unsigned long *)bh->b_data) {
1407 /* 0 and ~0 are special, we can optimize for them */
1408 if (*cur == 0)
1409 info->free_count += BITS_PER_LONG;
1410 else if (*cur != ~0L) /* A mix, investigate */
1411 info->free_count += BITS_PER_LONG - hweight_long(*cur);
1412 }
1413}
1414
1415struct buffer_head *reiserfs_read_bitmap_block(struct super_block *sb,
1416 unsigned int bitmap)
1417{
1418 b_blocknr_t block = (sb->s_blocksize << 3) * bitmap;
1419 struct reiserfs_bitmap_info *info = SB_AP_BITMAP(sb) + bitmap;
1420 struct buffer_head *bh;
1421
1422 /*
1423 * Way old format filesystems had the bitmaps packed up front.
1424 * I doubt there are any of these left, but just in case...
1425 */
1426 if (unlikely(test_bit(REISERFS_OLD_FORMAT,
1427 &REISERFS_SB(sb)->s_properties)))
1428 block = REISERFS_SB(sb)->s_sbh->b_blocknr + 1 + bitmap;
1429 else if (bitmap == 0)
1430 block = (REISERFS_DISK_OFFSET_IN_BYTES >> sb->s_blocksize_bits) + 1;
1431
1432 bh = sb_bread(sb, block);
1433 if (bh == NULL)
1434 reiserfs_warning(sb, "sh-2029: %s: bitmap block (#%u) "
1435 "reading failed", __func__, block);
1436 else {
1437 if (buffer_locked(bh)) {
1438 int depth;
1439 PROC_INFO_INC(sb, scan_bitmap.wait);
1440 depth = reiserfs_write_unlock_nested(sb);
1441 __wait_on_buffer(bh);
1442 reiserfs_write_lock_nested(sb, depth);
1443 }
1444 BUG_ON(!buffer_uptodate(bh));
1445 BUG_ON(atomic_read(&bh->b_count) == 0);
1446
1447 if (info->free_count == UINT_MAX)
1448 reiserfs_cache_bitmap_metadata(sb, bh, info);
1449 }
1450
1451 return bh;
1452}
1453
1454int reiserfs_init_bitmap_cache(struct super_block *sb)
1455{
1456 struct reiserfs_bitmap_info *bitmap;
1457 unsigned int bmap_nr = reiserfs_bmap_count(sb);
1458
1459 bitmap = vmalloc(array_size(bmap_nr, sizeof(*bitmap)));
1460 if (bitmap == NULL)
1461 return -ENOMEM;
1462
1463 memset(bitmap, 0xff, sizeof(*bitmap) * bmap_nr);
1464
1465 SB_AP_BITMAP(sb) = bitmap;
1466
1467 return 0;
1468}
1469
1470void reiserfs_free_bitmap_cache(struct super_block *sb)
1471{
1472 if (SB_AP_BITMAP(sb)) {
1473 vfree(SB_AP_BITMAP(sb));
1474 SB_AP_BITMAP(sb) = NULL;
1475 }
1476}