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spi-topcliff-pch: Fix issue for transmitting over 4KByte
[zen-stable.git] / fs / reiserfs / bitmap.c
blob70de42f09f1d1cfcef2c78aaf7552b851cb00099
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 #include <linux/seq_file.h>
17
18 #define PREALLOCATION_SIZE 9
19
20 /* different reiserfs block allocator options */
21
22 #define SB_ALLOC_OPTS(s) (REISERFS_SB(s)->s_alloc_options.bits)
23
24 #define _ALLOC_concentrating_formatted_nodes 0
25 #define _ALLOC_displacing_large_files 1
26 #define _ALLOC_displacing_new_packing_localities 2
27 #define _ALLOC_old_hashed_relocation 3
28 #define _ALLOC_new_hashed_relocation 4
29 #define _ALLOC_skip_busy 5
30 #define _ALLOC_displace_based_on_dirid 6
31 #define _ALLOC_hashed_formatted_nodes 7
32 #define _ALLOC_old_way 8
33 #define _ALLOC_hundredth_slices 9
34 #define _ALLOC_dirid_groups 10
35 #define _ALLOC_oid_groups 11
36 #define _ALLOC_packing_groups 12
37
38 #define concentrating_formatted_nodes(s) test_bit(_ALLOC_concentrating_formatted_nodes, &SB_ALLOC_OPTS(s))
39 #define displacing_large_files(s) test_bit(_ALLOC_displacing_large_files, &SB_ALLOC_OPTS(s))
40 #define displacing_new_packing_localities(s) test_bit(_ALLOC_displacing_new_packing_localities, &SB_ALLOC_OPTS(s))
41
42 #define SET_OPTION(optname) \
43 do { \
44 reiserfs_info(s, "block allocator option \"%s\" is set", #optname); \
45 set_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s)); \
46 } while(0)
47 #define TEST_OPTION(optname, s) \
48 test_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s))
49
50 static inline void get_bit_address(struct super_block *s,
51 b_blocknr_t block,
52 unsigned int *bmap_nr,
53 unsigned int *offset)
54 {
55 /* It is in the bitmap block number equal to the block
56 * number divided by the number of bits in a block. */
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
62 int 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 /* Old format filesystem? Unlikely, but the bitmaps are all up front so
77 * we need to account for it. */
78 if (unlikely(test_bit(REISERFS_OLD_FORMAT,
79 &(REISERFS_SB(s)->s_properties)))) {
80 b_blocknr_t bmap1 = REISERFS_SB(s)->s_sbh->b_blocknr + 1;
81 if (block >= bmap1 &&
82 block <= bmap1 + bmap_count) {
83 reiserfs_error(s, "vs-4019", "bitmap block %lu(%u) "
84 "can't be freed or reused",
85 block, bmap_count);
86 return 0;
87 }
88 } else {
89 if (offset == 0) {
90 reiserfs_error(s, "vs-4020", "bitmap block %lu(%u) "
91 "can't be freed or reused",
92 block, bmap_count);
93 return 0;
94 }
95 }
96
97 if (bmap >= bmap_count) {
98 reiserfs_error(s, "vs-4030", "bitmap for requested block "
99 "is out of range: block=%lu, bitmap_nr=%u",
100 block, bmap);
101 return 0;
102 }
103
104 if (bit_value == 0 && block == SB_ROOT_BLOCK(s)) {
105 reiserfs_error(s, "vs-4050", "this is root block (%u), "
106 "it must be busy", SB_ROOT_BLOCK(s));
107 return 0;
108 }
109
110 return 1;
111 }
112
113 /* searches in journal structures for a given block number (bmap, off). If block
114 is found in reiserfs journal it suggests next free block candidate to test. */
115 static inline int is_block_in_journal(struct super_block *s, unsigned int bmap,
116 int off, int *next)
117 {
118 b_blocknr_t tmp;
119
120 if (reiserfs_in_journal(s, bmap, off, 1, &tmp)) {
121 if (tmp) { /* hint supplied */
122 *next = tmp;
123 PROC_INFO_INC(s, scan_bitmap.in_journal_hint);
124 } else {
125 (*next) = off + 1; /* inc offset to avoid looping. */
126 PROC_INFO_INC(s, scan_bitmap.in_journal_nohint);
127 }
128 PROC_INFO_INC(s, scan_bitmap.retry);
129 return 1;
130 }
131 return 0;
132 }
133
134 /* it searches for a window of zero bits with given minimum and maximum lengths in one bitmap
135 * block; */
136 static int scan_bitmap_block(struct reiserfs_transaction_handle *th,
137 unsigned int bmap_n, int *beg, int boundary,
138 int min, int max, int unfm)
139 {
140 struct super_block *s = th->t_super;
141 struct reiserfs_bitmap_info *bi = &SB_AP_BITMAP(s)[bmap_n];
142 struct buffer_head *bh;
143 int end, next;
144 int org = *beg;
145
146 BUG_ON(!th->t_trans_id);
147
148 RFALSE(bmap_n >= reiserfs_bmap_count(s), "Bitmap %u is out of "
149 "range (0..%u)", bmap_n, reiserfs_bmap_count(s) - 1);
150 PROC_INFO_INC(s, scan_bitmap.bmap);
151 /* this is unclear and lacks comments, explain how journal bitmaps
152 work here for the reader. Convey a sense of the design here. What
153 is a window? */
154 /* - I mean `a window of zero bits' as in description of this function - Zam. */
155
156 if (!bi) {
157 reiserfs_error(s, "jdm-4055", "NULL bitmap info pointer "
158 "for bitmap %d", bmap_n);
159 return 0;
160 }
161
162 bh = reiserfs_read_bitmap_block(s, bmap_n);
163 if (bh == NULL)
164 return 0;
165
166 while (1) {
167 cont:
168 if (bi->free_count < min) {
169 brelse(bh);
170 return 0; // No free blocks in this bitmap
171 }
172
173 /* search for a first zero bit -- beginning of a window */
174 *beg = reiserfs_find_next_zero_le_bit
175 ((unsigned long *)(bh->b_data), boundary, *beg);
176
177 if (*beg + min > boundary) { /* search for a zero bit fails or the rest of bitmap block
178 * cannot contain a zero window of minimum size */
179 brelse(bh);
180 return 0;
181 }
182
183 if (unfm && is_block_in_journal(s, bmap_n, *beg, beg))
184 continue;
185 /* first zero bit found; we check next bits */
186 for (end = *beg + 1;; end++) {
187 if (end >= *beg + max || end >= boundary
188 || reiserfs_test_le_bit(end, bh->b_data)) {
189 next = end;
190 break;
191 }
192 /* finding the other end of zero bit window requires looking into journal structures (in
193 * case of searching for free blocks for unformatted nodes) */
194 if (unfm && is_block_in_journal(s, bmap_n, end, &next))
195 break;
196 }
197
198 /* now (*beg) points to beginning of zero bits window,
199 * (end) points to one bit after the window end */
200 if (end - *beg >= min) { /* it seems we have found window of proper size */
201 int i;
202 reiserfs_prepare_for_journal(s, bh, 1);
203 /* try to set all blocks used checking are they still free */
204 for (i = *beg; i < end; i++) {
205 /* It seems that we should not check in journal again. */
206 if (reiserfs_test_and_set_le_bit
207 (i, bh->b_data)) {
208 /* bit was set by another process
209 * while we slept in prepare_for_journal() */
210 PROC_INFO_INC(s, scan_bitmap.stolen);
211 if (i >= *beg + min) { /* we can continue with smaller set of allocated blocks,
212 * if length of this set is more or equal to `min' */
213 end = i;
214 break;
215 }
216 /* otherwise we clear all bit were set ... */
217 while (--i >= *beg)
218 reiserfs_clear_le_bit
219 (i, bh->b_data);
220 reiserfs_restore_prepared_buffer(s, bh);
221 *beg = org;
222 /* ... and search again in current block from beginning */
223 goto cont;
224 }
225 }
226 bi->free_count -= (end - *beg);
227 journal_mark_dirty(th, s, bh);
228 brelse(bh);
229
230 /* free block count calculation */
231 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s),
232 1);
233 PUT_SB_FREE_BLOCKS(s, SB_FREE_BLOCKS(s) - (end - *beg));
234 journal_mark_dirty(th, s, SB_BUFFER_WITH_SB(s));
235
236 return end - (*beg);
237 } else {
238 *beg = next;
239 }
240 }
241 }
242
243 static int bmap_hash_id(struct super_block *s, u32 id)
244 {
245 char *hash_in = NULL;
246 unsigned long hash;
247 unsigned bm;
248
249 if (id <= 2) {
250 bm = 1;
251 } else {
252 hash_in = (char *)(&id);
253 hash = keyed_hash(hash_in, 4);
254 bm = hash % reiserfs_bmap_count(s);
255 if (!bm)
256 bm = 1;
257 }
258 /* this can only be true when SB_BMAP_NR = 1 */
259 if (bm >= reiserfs_bmap_count(s))
260 bm = 0;
261 return bm;
262 }
263
264 /*
265 * hashes the id and then returns > 0 if the block group for the
266 * corresponding hash is full
267 */
268 static inline int block_group_used(struct super_block *s, u32 id)
269 {
270 int bm = bmap_hash_id(s, id);
271 struct reiserfs_bitmap_info *info = &SB_AP_BITMAP(s)[bm];
272
273 /* If we don't have cached information on this bitmap block, we're
274 * going to have to load it later anyway. Loading it here allows us
275 * to make a better decision. This favors long-term performance gain
276 * with a better on-disk layout vs. a short term gain of skipping the
277 * read and potentially having a bad placement. */
278 if (info->free_count == UINT_MAX) {
279 struct buffer_head *bh = reiserfs_read_bitmap_block(s, bm);
280 brelse(bh);
281 }
282
283 if (info->free_count > ((s->s_blocksize << 3) * 60 / 100)) {
284 return 0;
285 }
286 return 1;
287 }
288
289 /*
290 * the packing is returned in disk byte order
291 */
292 __le32 reiserfs_choose_packing(struct inode * dir)
293 {
294 __le32 packing;
295 if (TEST_OPTION(packing_groups, dir->i_sb)) {
296 u32 parent_dir = le32_to_cpu(INODE_PKEY(dir)->k_dir_id);
297 /*
298 * some versions of reiserfsck expect packing locality 1 to be
299 * special
300 */
301 if (parent_dir == 1 || block_group_used(dir->i_sb, parent_dir))
302 packing = INODE_PKEY(dir)->k_objectid;
303 else
304 packing = INODE_PKEY(dir)->k_dir_id;
305 } else
306 packing = INODE_PKEY(dir)->k_objectid;
307 return packing;
308 }
309
310 /* Tries to find contiguous zero bit window (given size) in given region of
311 * bitmap and place new blocks there. Returns number of allocated blocks. */
312 static int scan_bitmap(struct reiserfs_transaction_handle *th,
313 b_blocknr_t * start, b_blocknr_t finish,
314 int min, int max, int unfm, sector_t file_block)
315 {
316 int nr_allocated = 0;
317 struct super_block *s = th->t_super;
318 /* find every bm and bmap and bmap_nr in this file, and change them all to bitmap_blocknr
319 * - Hans, it is not a block number - Zam. */
320
321 unsigned int bm, off;
322 unsigned int end_bm, end_off;
323 unsigned int off_max = s->s_blocksize << 3;
324
325 BUG_ON(!th->t_trans_id);
326
327 PROC_INFO_INC(s, scan_bitmap.call);
328 if (SB_FREE_BLOCKS(s) <= 0)
329 return 0; // No point in looking for more free blocks
330
331 get_bit_address(s, *start, &bm, &off);
332 get_bit_address(s, finish, &end_bm, &end_off);
333 if (bm > reiserfs_bmap_count(s))
334 return 0;
335 if (end_bm > reiserfs_bmap_count(s))
336 end_bm = reiserfs_bmap_count(s);
337
338 /* When the bitmap is more than 10% free, anyone can allocate.
339 * When it's less than 10% free, only files that already use the
340 * bitmap are allowed. Once we pass 80% full, this restriction
341 * is lifted.
342 *
343 * We do this so that files that grow later still have space close to
344 * their original allocation. This improves locality, and presumably
345 * performance as a result.
346 *
347 * This is only an allocation policy and does not make up for getting a
348 * bad hint. Decent hinting must be implemented for this to work well.
349 */
350 if (TEST_OPTION(skip_busy, s)
351 && SB_FREE_BLOCKS(s) > SB_BLOCK_COUNT(s) / 20) {
352 for (; bm < end_bm; bm++, off = 0) {
353 if ((off && (!unfm || (file_block != 0)))
354 || SB_AP_BITMAP(s)[bm].free_count >
355 (s->s_blocksize << 3) / 10)
356 nr_allocated =
357 scan_bitmap_block(th, bm, &off, off_max,
358 min, max, unfm);
359 if (nr_allocated)
360 goto ret;
361 }
362 /* we know from above that start is a reasonable number */
363 get_bit_address(s, *start, &bm, &off);
364 }
365
366 for (; bm < end_bm; bm++, off = 0) {
367 nr_allocated =
368 scan_bitmap_block(th, bm, &off, off_max, min, max, unfm);
369 if (nr_allocated)
370 goto ret;
371 }
372
373 nr_allocated =
374 scan_bitmap_block(th, bm, &off, end_off + 1, min, max, unfm);
375
376 ret:
377 *start = bm * off_max + off;
378 return nr_allocated;
379
380 }
381
382 static void _reiserfs_free_block(struct reiserfs_transaction_handle *th,
383 struct inode *inode, b_blocknr_t block,
384 int for_unformatted)
385 {
386 struct super_block *s = th->t_super;
387 struct reiserfs_super_block *rs;
388 struct buffer_head *sbh, *bmbh;
389 struct reiserfs_bitmap_info *apbi;
390 unsigned int nr, offset;
391
392 BUG_ON(!th->t_trans_id);
393
394 PROC_INFO_INC(s, free_block);
395
396 rs = SB_DISK_SUPER_BLOCK(s);
397 sbh = SB_BUFFER_WITH_SB(s);
398 apbi = SB_AP_BITMAP(s);
399
400 get_bit_address(s, block, &nr, &offset);
401
402 if (nr >= reiserfs_bmap_count(s)) {
403 reiserfs_error(s, "vs-4075", "block %lu is out of range",
404 block);
405 return;
406 }
407
408 bmbh = reiserfs_read_bitmap_block(s, nr);
409 if (!bmbh)
410 return;
411
412 reiserfs_prepare_for_journal(s, bmbh, 1);
413
414 /* clear bit for the given block in bit map */
415 if (!reiserfs_test_and_clear_le_bit(offset, bmbh->b_data)) {
416 reiserfs_error(s, "vs-4080",
417 "block %lu: bit already cleared", block);
418 }
419 apbi[nr].free_count++;
420 journal_mark_dirty(th, s, bmbh);
421 brelse(bmbh);
422
423 reiserfs_prepare_for_journal(s, sbh, 1);
424 /* update super block */
425 set_sb_free_blocks(rs, sb_free_blocks(rs) + 1);
426
427 journal_mark_dirty(th, s, sbh);
428 if (for_unformatted)
429 dquot_free_block_nodirty(inode, 1);
430 }
431
432 void reiserfs_free_block(struct reiserfs_transaction_handle *th,
433 struct inode *inode, b_blocknr_t block,
434 int for_unformatted)
435 {
436 struct super_block *s = th->t_super;
437 BUG_ON(!th->t_trans_id);
438
439 RFALSE(!s, "vs-4061: trying to free block on nonexistent device");
440 if (!is_reusable(s, block, 1))
441 return;
442
443 if (block > sb_block_count(REISERFS_SB(s)->s_rs)) {
444 reiserfs_error(th->t_super, "bitmap-4072",
445 "Trying to free block outside file system "
446 "boundaries (%lu > %lu)",
447 block, sb_block_count(REISERFS_SB(s)->s_rs));
448 return;
449 }
450 /* mark it before we clear it, just in case */
451 journal_mark_freed(th, s, block);
452 _reiserfs_free_block(th, inode, block, for_unformatted);
453 }
454
455 /* preallocated blocks don't need to be run through journal_mark_freed */
456 static void reiserfs_free_prealloc_block(struct reiserfs_transaction_handle *th,
457 struct inode *inode, b_blocknr_t block)
458 {
459 BUG_ON(!th->t_trans_id);
460 RFALSE(!th->t_super,
461 "vs-4060: trying to free block on nonexistent device");
462 if (!is_reusable(th->t_super, block, 1))
463 return;
464 _reiserfs_free_block(th, inode, block, 1);
465 }
466
467 static void __discard_prealloc(struct reiserfs_transaction_handle *th,
468 struct reiserfs_inode_info *ei)
469 {
470 unsigned long save = ei->i_prealloc_block;
471 int dirty = 0;
472 struct inode *inode = &ei->vfs_inode;
473 BUG_ON(!th->t_trans_id);
474 #ifdef CONFIG_REISERFS_CHECK
475 if (ei->i_prealloc_count < 0)
476 reiserfs_error(th->t_super, "zam-4001",
477 "inode has negative prealloc blocks count.");
478 #endif
479 while (ei->i_prealloc_count > 0) {
480 reiserfs_free_prealloc_block(th, inode, ei->i_prealloc_block);
481 ei->i_prealloc_block++;
482 ei->i_prealloc_count--;
483 dirty = 1;
484 }
485 if (dirty)
486 reiserfs_update_sd(th, inode);
487 ei->i_prealloc_block = save;
488 list_del_init(&(ei->i_prealloc_list));
489 }
490
491 /* FIXME: It should be inline function */
492 void reiserfs_discard_prealloc(struct reiserfs_transaction_handle *th,
493 struct inode *inode)
494 {
495 struct reiserfs_inode_info *ei = REISERFS_I(inode);
496 BUG_ON(!th->t_trans_id);
497 if (ei->i_prealloc_count)
498 __discard_prealloc(th, ei);
499 }
500
501 void reiserfs_discard_all_prealloc(struct reiserfs_transaction_handle *th)
502 {
503 struct list_head *plist = &SB_JOURNAL(th->t_super)->j_prealloc_list;
504
505 BUG_ON(!th->t_trans_id);
506
507 while (!list_empty(plist)) {
508 struct reiserfs_inode_info *ei;
509 ei = list_entry(plist->next, struct reiserfs_inode_info,
510 i_prealloc_list);
511 #ifdef CONFIG_REISERFS_CHECK
512 if (!ei->i_prealloc_count) {
513 reiserfs_error(th->t_super, "zam-4001",
514 "inode is in prealloc list but has "
515 "no preallocated blocks.");
516 }
517 #endif
518 __discard_prealloc(th, ei);
519 }
520 }
521
522 void reiserfs_init_alloc_options(struct super_block *s)
523 {
524 set_bit(_ALLOC_skip_busy, &SB_ALLOC_OPTS(s));
525 set_bit(_ALLOC_dirid_groups, &SB_ALLOC_OPTS(s));
526 set_bit(_ALLOC_packing_groups, &SB_ALLOC_OPTS(s));
527 }
528
529 /* block allocator related options are parsed here */
530 int reiserfs_parse_alloc_options(struct super_block *s, char *options)
531 {
532 char *this_char, *value;
533
534 REISERFS_SB(s)->s_alloc_options.bits = 0; /* clear default settings */
535
536 while ((this_char = strsep(&options, ":")) != NULL) {
537 if ((value = strchr(this_char, '=')) != NULL)
538 *value++ = 0;
539
540 if (!strcmp(this_char, "concentrating_formatted_nodes")) {
541 int temp;
542 SET_OPTION(concentrating_formatted_nodes);
543 temp = (value
544 && *value) ? simple_strtoul(value, &value,
545 0) : 10;
546 if (temp <= 0 || temp > 100) {
547 REISERFS_SB(s)->s_alloc_options.border = 10;
548 } else {
549 REISERFS_SB(s)->s_alloc_options.border =
550 100 / temp;
551 }
552 continue;
553 }
554 if (!strcmp(this_char, "displacing_large_files")) {
555 SET_OPTION(displacing_large_files);
556 REISERFS_SB(s)->s_alloc_options.large_file_size =
557 (value
558 && *value) ? simple_strtoul(value, &value, 0) : 16;
559 continue;
560 }
561 if (!strcmp(this_char, "displacing_new_packing_localities")) {
562 SET_OPTION(displacing_new_packing_localities);
563 continue;
564 };
565
566 if (!strcmp(this_char, "old_hashed_relocation")) {
567 SET_OPTION(old_hashed_relocation);
568 continue;
569 }
570
571 if (!strcmp(this_char, "new_hashed_relocation")) {
572 SET_OPTION(new_hashed_relocation);
573 continue;
574 }
575
576 if (!strcmp(this_char, "dirid_groups")) {
577 SET_OPTION(dirid_groups);
578 continue;
579 }
580 if (!strcmp(this_char, "oid_groups")) {
581 SET_OPTION(oid_groups);
582 continue;
583 }
584 if (!strcmp(this_char, "packing_groups")) {
585 SET_OPTION(packing_groups);
586 continue;
587 }
588 if (!strcmp(this_char, "hashed_formatted_nodes")) {
589 SET_OPTION(hashed_formatted_nodes);
590 continue;
591 }
592
593 if (!strcmp(this_char, "skip_busy")) {
594 SET_OPTION(skip_busy);
595 continue;
596 }
597
598 if (!strcmp(this_char, "hundredth_slices")) {
599 SET_OPTION(hundredth_slices);
600 continue;
601 }
602
603 if (!strcmp(this_char, "old_way")) {
604 SET_OPTION(old_way);
605 continue;
606 }
607
608 if (!strcmp(this_char, "displace_based_on_dirid")) {
609 SET_OPTION(displace_based_on_dirid);
610 continue;
611 }
612
613 if (!strcmp(this_char, "preallocmin")) {
614 REISERFS_SB(s)->s_alloc_options.preallocmin =
615 (value
616 && *value) ? simple_strtoul(value, &value, 0) : 4;
617 continue;
618 }
619
620 if (!strcmp(this_char, "preallocsize")) {
621 REISERFS_SB(s)->s_alloc_options.preallocsize =
622 (value
623 && *value) ? simple_strtoul(value, &value,
624 0) :
625 PREALLOCATION_SIZE;
626 continue;
627 }
628
629 reiserfs_warning(s, "zam-4001", "unknown option - %s",
630 this_char);
631 return 1;
632 }
633
634 reiserfs_info(s, "allocator options = [%08x]\n", SB_ALLOC_OPTS(s));
635 return 0;
636 }
637
638 static void print_sep(struct seq_file *seq, int *first)
639 {
640 if (!*first)
641 seq_puts(seq, ":");
642 else
643 *first = 0;
644 }
645
646 void show_alloc_options(struct seq_file *seq, struct super_block *s)
647 {
648 int first = 1;
649
650 if (SB_ALLOC_OPTS(s) == ((1 << _ALLOC_skip_busy) |
651 (1 << _ALLOC_dirid_groups) | (1 << _ALLOC_packing_groups)))
652 return;
653
654 seq_puts(seq, ",alloc=");
655
656 if (TEST_OPTION(concentrating_formatted_nodes, s)) {
657 print_sep(seq, &first);
658 if (REISERFS_SB(s)->s_alloc_options.border != 10) {
659 seq_printf(seq, "concentrating_formatted_nodes=%d",
660 100 / REISERFS_SB(s)->s_alloc_options.border);
661 } else
662 seq_puts(seq, "concentrating_formatted_nodes");
663 }
664 if (TEST_OPTION(displacing_large_files, s)) {
665 print_sep(seq, &first);
666 if (REISERFS_SB(s)->s_alloc_options.large_file_size != 16) {
667 seq_printf(seq, "displacing_large_files=%lu",
668 REISERFS_SB(s)->s_alloc_options.large_file_size);
669 } else
670 seq_puts(seq, "displacing_large_files");
671 }
672 if (TEST_OPTION(displacing_new_packing_localities, s)) {
673 print_sep(seq, &first);
674 seq_puts(seq, "displacing_new_packing_localities");
675 }
676 if (TEST_OPTION(old_hashed_relocation, s)) {
677 print_sep(seq, &first);
678 seq_puts(seq, "old_hashed_relocation");
679 }
680 if (TEST_OPTION(new_hashed_relocation, s)) {
681 print_sep(seq, &first);
682 seq_puts(seq, "new_hashed_relocation");
683 }
684 if (TEST_OPTION(dirid_groups, s)) {
685 print_sep(seq, &first);
686 seq_puts(seq, "dirid_groups");
687 }
688 if (TEST_OPTION(oid_groups, s)) {
689 print_sep(seq, &first);
690 seq_puts(seq, "oid_groups");
691 }
692 if (TEST_OPTION(packing_groups, s)) {
693 print_sep(seq, &first);
694 seq_puts(seq, "packing_groups");
695 }
696 if (TEST_OPTION(hashed_formatted_nodes, s)) {
697 print_sep(seq, &first);
698 seq_puts(seq, "hashed_formatted_nodes");
699 }
700 if (TEST_OPTION(skip_busy, s)) {
701 print_sep(seq, &first);
702 seq_puts(seq, "skip_busy");
703 }
704 if (TEST_OPTION(hundredth_slices, s)) {
705 print_sep(seq, &first);
706 seq_puts(seq, "hundredth_slices");
707 }
708 if (TEST_OPTION(old_way, s)) {
709 print_sep(seq, &first);
710 seq_puts(seq, "old_way");
711 }
712 if (TEST_OPTION(displace_based_on_dirid, s)) {
713 print_sep(seq, &first);
714 seq_puts(seq, "displace_based_on_dirid");
715 }
716 if (REISERFS_SB(s)->s_alloc_options.preallocmin != 0) {
717 print_sep(seq, &first);
718 seq_printf(seq, "preallocmin=%d",
719 REISERFS_SB(s)->s_alloc_options.preallocmin);
720 }
721 if (REISERFS_SB(s)->s_alloc_options.preallocsize != 17) {
722 print_sep(seq, &first);
723 seq_printf(seq, "preallocsize=%d",
724 REISERFS_SB(s)->s_alloc_options.preallocsize);
725 }
726 }
727
728 static inline void new_hashed_relocation(reiserfs_blocknr_hint_t * hint)
729 {
730 char *hash_in;
731 if (hint->formatted_node) {
732 hash_in = (char *)&hint->key.k_dir_id;
733 } else {
734 if (!hint->inode) {
735 //hint->search_start = hint->beg;
736 hash_in = (char *)&hint->key.k_dir_id;
737 } else
738 if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
739 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
740 else
741 hash_in =
742 (char *)(&INODE_PKEY(hint->inode)->k_objectid);
743 }
744
745 hint->search_start =
746 hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
747 }
748
749 /*
750 * Relocation based on dirid, hashing them into a given bitmap block
751 * files. Formatted nodes are unaffected, a separate policy covers them
752 */
753 static void dirid_groups(reiserfs_blocknr_hint_t * hint)
754 {
755 unsigned long hash;
756 __u32 dirid = 0;
757 int bm = 0;
758 struct super_block *sb = hint->th->t_super;
759 if (hint->inode)
760 dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
761 else if (hint->formatted_node)
762 dirid = hint->key.k_dir_id;
763
764 if (dirid) {
765 bm = bmap_hash_id(sb, dirid);
766 hash = bm * (sb->s_blocksize << 3);
767 /* give a portion of the block group to metadata */
768 if (hint->inode)
769 hash += sb->s_blocksize / 2;
770 hint->search_start = hash;
771 }
772 }
773
774 /*
775 * Relocation based on oid, hashing them into a given bitmap block
776 * files. Formatted nodes are unaffected, a separate policy covers them
777 */
778 static void oid_groups(reiserfs_blocknr_hint_t * hint)
779 {
780 if (hint->inode) {
781 unsigned long hash;
782 __u32 oid;
783 __u32 dirid;
784 int bm;
785
786 dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
787
788 /* keep the root dir and it's first set of subdirs close to
789 * the start of the disk
790 */
791 if (dirid <= 2)
792 hash = (hint->inode->i_sb->s_blocksize << 3);
793 else {
794 oid = le32_to_cpu(INODE_PKEY(hint->inode)->k_objectid);
795 bm = bmap_hash_id(hint->inode->i_sb, oid);
796 hash = bm * (hint->inode->i_sb->s_blocksize << 3);
797 }
798 hint->search_start = hash;
799 }
800 }
801
802 /* returns 1 if it finds an indirect item and gets valid hint info
803 * from it, otherwise 0
804 */
805 static int get_left_neighbor(reiserfs_blocknr_hint_t * hint)
806 {
807 struct treepath *path;
808 struct buffer_head *bh;
809 struct item_head *ih;
810 int pos_in_item;
811 __le32 *item;
812 int ret = 0;
813
814 if (!hint->path) /* reiserfs code can call this function w/o pointer to path
815 * structure supplied; then we rely on supplied search_start */
816 return 0;
817
818 path = hint->path;
819 bh = get_last_bh(path);
820 RFALSE(!bh, "green-4002: Illegal path specified to get_left_neighbor");
821 ih = get_ih(path);
822 pos_in_item = path->pos_in_item;
823 item = get_item(path);
824
825 hint->search_start = bh->b_blocknr;
826
827 if (!hint->formatted_node && is_indirect_le_ih(ih)) {
828 /* for indirect item: go to left and look for the first non-hole entry
829 in the indirect item */
830 if (pos_in_item == I_UNFM_NUM(ih))
831 pos_in_item--;
832 // pos_in_item = I_UNFM_NUM (ih) - 1;
833 while (pos_in_item >= 0) {
834 int t = get_block_num(item, pos_in_item);
835 if (t) {
836 hint->search_start = t;
837 ret = 1;
838 break;
839 }
840 pos_in_item--;
841 }
842 }
843
844 /* does result value fit into specified region? */
845 return ret;
846 }
847
848 /* should be, if formatted node, then try to put on first part of the device
849 specified as number of percent with mount option device, else try to put
850 on last of device. This is not to say it is good code to do so,
851 but the effect should be measured. */
852 static inline void set_border_in_hint(struct super_block *s,
853 reiserfs_blocknr_hint_t * hint)
854 {
855 b_blocknr_t border =
856 SB_BLOCK_COUNT(s) / REISERFS_SB(s)->s_alloc_options.border;
857
858 if (hint->formatted_node)
859 hint->end = border - 1;
860 else
861 hint->beg = border;
862 }
863
864 static inline void displace_large_file(reiserfs_blocknr_hint_t * hint)
865 {
866 if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
867 hint->search_start =
868 hint->beg +
869 keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_dir_id),
870 4) % (hint->end - hint->beg);
871 else
872 hint->search_start =
873 hint->beg +
874 keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_objectid),
875 4) % (hint->end - hint->beg);
876 }
877
878 static inline void hash_formatted_node(reiserfs_blocknr_hint_t * hint)
879 {
880 char *hash_in;
881
882 if (!hint->inode)
883 hash_in = (char *)&hint->key.k_dir_id;
884 else if (TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
885 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
886 else
887 hash_in = (char *)(&INODE_PKEY(hint->inode)->k_objectid);
888
889 hint->search_start =
890 hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
891 }
892
893 static inline int
894 this_blocknr_allocation_would_make_it_a_large_file(reiserfs_blocknr_hint_t *
895 hint)
896 {
897 return hint->block ==
898 REISERFS_SB(hint->th->t_super)->s_alloc_options.large_file_size;
899 }
900
901 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
902 static inline void displace_new_packing_locality(reiserfs_blocknr_hint_t * hint)
903 {
904 struct in_core_key *key = &hint->key;
905
906 hint->th->displace_new_blocks = 0;
907 hint->search_start =
908 hint->beg + keyed_hash((char *)(&key->k_objectid),
909 4) % (hint->end - hint->beg);
910 }
911 #endif
912
913 static inline int old_hashed_relocation(reiserfs_blocknr_hint_t * hint)
914 {
915 b_blocknr_t border;
916 u32 hash_in;
917
918 if (hint->formatted_node || hint->inode == NULL) {
919 return 0;
920 }
921
922 hash_in = le32_to_cpu((INODE_PKEY(hint->inode))->k_dir_id);
923 border =
924 hint->beg + (u32) keyed_hash(((char *)(&hash_in)),
925 4) % (hint->end - hint->beg - 1);
926 if (border > hint->search_start)
927 hint->search_start = border;
928
929 return 1;
930 }
931
932 static inline int old_way(reiserfs_blocknr_hint_t * hint)
933 {
934 b_blocknr_t border;
935
936 if (hint->formatted_node || hint->inode == NULL) {
937 return 0;
938 }
939
940 border =
941 hint->beg +
942 le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id) % (hint->end -
943 hint->beg);
944 if (border > hint->search_start)
945 hint->search_start = border;
946
947 return 1;
948 }
949
950 static inline void hundredth_slices(reiserfs_blocknr_hint_t * hint)
951 {
952 struct in_core_key *key = &hint->key;
953 b_blocknr_t slice_start;
954
955 slice_start =
956 (keyed_hash((char *)(&key->k_dir_id), 4) % 100) * (hint->end / 100);
957 if (slice_start > hint->search_start
958 || slice_start + (hint->end / 100) <= hint->search_start) {
959 hint->search_start = slice_start;
960 }
961 }
962
963 static void determine_search_start(reiserfs_blocknr_hint_t * hint,
964 int amount_needed)
965 {
966 struct super_block *s = hint->th->t_super;
967 int unfm_hint;
968
969 hint->beg = 0;
970 hint->end = SB_BLOCK_COUNT(s) - 1;
971
972 /* This is former border algorithm. Now with tunable border offset */
973 if (concentrating_formatted_nodes(s))
974 set_border_in_hint(s, hint);
975
976 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
977 /* whenever we create a new directory, we displace it. At first we will
978 hash for location, later we might look for a moderately empty place for
979 it */
980 if (displacing_new_packing_localities(s)
981 && hint->th->displace_new_blocks) {
982 displace_new_packing_locality(hint);
983
984 /* we do not continue determine_search_start,
985 * if new packing locality is being displaced */
986 return;
987 }
988 #endif
989
990 /* all persons should feel encouraged to add more special cases here and
991 * test them */
992
993 if (displacing_large_files(s) && !hint->formatted_node
994 && this_blocknr_allocation_would_make_it_a_large_file(hint)) {
995 displace_large_file(hint);
996 return;
997 }
998
999 /* if none of our special cases is relevant, use the left neighbor in the
1000 tree order of the new node we are allocating for */
1001 if (hint->formatted_node && TEST_OPTION(hashed_formatted_nodes, s)) {
1002 hash_formatted_node(hint);
1003 return;
1004 }
1005
1006 unfm_hint = get_left_neighbor(hint);
1007
1008 /* Mimic old block allocator behaviour, that is if VFS allowed for preallocation,
1009 new blocks are displaced based on directory ID. Also, if suggested search_start
1010 is less than last preallocated block, we start searching from it, assuming that
1011 HDD dataflow is faster in forward direction */
1012 if (TEST_OPTION(old_way, s)) {
1013 if (!hint->formatted_node) {
1014 if (!reiserfs_hashed_relocation(s))
1015 old_way(hint);
1016 else if (!reiserfs_no_unhashed_relocation(s))
1017 old_hashed_relocation(hint);
1018
1019 if (hint->inode
1020 && hint->search_start <
1021 REISERFS_I(hint->inode)->i_prealloc_block)
1022 hint->search_start =
1023 REISERFS_I(hint->inode)->i_prealloc_block;
1024 }
1025 return;
1026 }
1027
1028 /* This is an approach proposed by Hans */
1029 if (TEST_OPTION(hundredth_slices, s)
1030 && !(displacing_large_files(s) && !hint->formatted_node)) {
1031 hundredth_slices(hint);
1032 return;
1033 }
1034
1035 /* old_hashed_relocation only works on unformatted */
1036 if (!unfm_hint && !hint->formatted_node &&
1037 TEST_OPTION(old_hashed_relocation, s)) {
1038 old_hashed_relocation(hint);
1039 }
1040 /* new_hashed_relocation works with both formatted/unformatted nodes */
1041 if ((!unfm_hint || hint->formatted_node) &&
1042 TEST_OPTION(new_hashed_relocation, s)) {
1043 new_hashed_relocation(hint);
1044 }
1045 /* dirid grouping works only on unformatted nodes */
1046 if (!unfm_hint && !hint->formatted_node && TEST_OPTION(dirid_groups, s)) {
1047 dirid_groups(hint);
1048 }
1049 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
1050 if (hint->formatted_node && TEST_OPTION(dirid_groups, s)) {
1051 dirid_groups(hint);
1052 }
1053 #endif
1054
1055 /* oid grouping works only on unformatted nodes */
1056 if (!unfm_hint && !hint->formatted_node && TEST_OPTION(oid_groups, s)) {
1057 oid_groups(hint);
1058 }
1059 return;
1060 }
1061
1062 static int determine_prealloc_size(reiserfs_blocknr_hint_t * hint)
1063 {
1064 /* make minimum size a mount option and benchmark both ways */
1065 /* we preallocate blocks only for regular files, specific size */
1066 /* benchmark preallocating always and see what happens */
1067
1068 hint->prealloc_size = 0;
1069
1070 if (!hint->formatted_node && hint->preallocate) {
1071 if (S_ISREG(hint->inode->i_mode)
1072 && hint->inode->i_size >=
1073 REISERFS_SB(hint->th->t_super)->s_alloc_options.
1074 preallocmin * hint->inode->i_sb->s_blocksize)
1075 hint->prealloc_size =
1076 REISERFS_SB(hint->th->t_super)->s_alloc_options.
1077 preallocsize - 1;
1078 }
1079 return CARRY_ON;
1080 }
1081
1082 /* XXX I know it could be merged with upper-level function;
1083 but may be result function would be too complex. */
1084 static inline int allocate_without_wrapping_disk(reiserfs_blocknr_hint_t * hint,
1085 b_blocknr_t * new_blocknrs,
1086 b_blocknr_t start,
1087 b_blocknr_t finish, int min,
1088 int amount_needed,
1089 int prealloc_size)
1090 {
1091 int rest = amount_needed;
1092 int nr_allocated;
1093
1094 while (rest > 0 && start <= finish) {
1095 nr_allocated = scan_bitmap(hint->th, &start, finish, min,
1096 rest + prealloc_size,
1097 !hint->formatted_node, hint->block);
1098
1099 if (nr_allocated == 0) /* no new blocks allocated, return */
1100 break;
1101
1102 /* fill free_blocknrs array first */
1103 while (rest > 0 && nr_allocated > 0) {
1104 *new_blocknrs++ = start++;
1105 rest--;
1106 nr_allocated--;
1107 }
1108
1109 /* do we have something to fill prealloc. array also ? */
1110 if (nr_allocated > 0) {
1111 /* it means prealloc_size was greater that 0 and we do preallocation */
1112 list_add(&REISERFS_I(hint->inode)->i_prealloc_list,
1113 &SB_JOURNAL(hint->th->t_super)->
1114 j_prealloc_list);
1115 REISERFS_I(hint->inode)->i_prealloc_block = start;
1116 REISERFS_I(hint->inode)->i_prealloc_count =
1117 nr_allocated;
1118 break;
1119 }
1120 }
1121
1122 return (amount_needed - rest);
1123 }
1124
1125 static inline int blocknrs_and_prealloc_arrays_from_search_start
1126 (reiserfs_blocknr_hint_t * hint, b_blocknr_t * new_blocknrs,
1127 int amount_needed) {
1128 struct super_block *s = hint->th->t_super;
1129 b_blocknr_t start = hint->search_start;
1130 b_blocknr_t finish = SB_BLOCK_COUNT(s) - 1;
1131 int passno = 0;
1132 int nr_allocated = 0;
1133
1134 determine_prealloc_size(hint);
1135 if (!hint->formatted_node) {
1136 int quota_ret;
1137 #ifdef REISERQUOTA_DEBUG
1138 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1139 "reiserquota: allocating %d blocks id=%u",
1140 amount_needed, hint->inode->i_uid);
1141 #endif
1142 quota_ret =
1143 dquot_alloc_block_nodirty(hint->inode, amount_needed);
1144 if (quota_ret) /* Quota exceeded? */
1145 return QUOTA_EXCEEDED;
1146 if (hint->preallocate && hint->prealloc_size) {
1147 #ifdef REISERQUOTA_DEBUG
1148 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1149 "reiserquota: allocating (prealloc) %d blocks id=%u",
1150 hint->prealloc_size, hint->inode->i_uid);
1151 #endif
1152 quota_ret = dquot_prealloc_block_nodirty(hint->inode,
1153 hint->prealloc_size);
1154 if (quota_ret)
1155 hint->preallocate = hint->prealloc_size = 0;
1156 }
1157 /* for unformatted nodes, force large allocations */
1158 }
1159
1160 do {
1161 switch (passno++) {
1162 case 0: /* Search from hint->search_start to end of disk */
1163 start = hint->search_start;
1164 finish = SB_BLOCK_COUNT(s) - 1;
1165 break;
1166 case 1: /* Search from hint->beg to hint->search_start */
1167 start = hint->beg;
1168 finish = hint->search_start;
1169 break;
1170 case 2: /* Last chance: Search from 0 to hint->beg */
1171 start = 0;
1172 finish = hint->beg;
1173 break;
1174 default: /* We've tried searching everywhere, not enough space */
1175 /* Free the blocks */
1176 if (!hint->formatted_node) {
1177 #ifdef REISERQUOTA_DEBUG
1178 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1179 "reiserquota: freeing (nospace) %d blocks id=%u",
1180 amount_needed +
1181 hint->prealloc_size -
1182 nr_allocated,
1183 hint->inode->i_uid);
1184 #endif
1185 /* Free not allocated blocks */
1186 dquot_free_block_nodirty(hint->inode,
1187 amount_needed + hint->prealloc_size -
1188 nr_allocated);
1189 }
1190 while (nr_allocated--)
1191 reiserfs_free_block(hint->th, hint->inode,
1192 new_blocknrs[nr_allocated],
1193 !hint->formatted_node);
1194
1195 return NO_DISK_SPACE;
1196 }
1197 } while ((nr_allocated += allocate_without_wrapping_disk(hint,
1198 new_blocknrs +
1199 nr_allocated,
1200 start, finish,
1201 1,
1202 amount_needed -
1203 nr_allocated,
1204 hint->
1205 prealloc_size))
1206 < amount_needed);
1207 if (!hint->formatted_node &&
1208 amount_needed + hint->prealloc_size >
1209 nr_allocated + REISERFS_I(hint->inode)->i_prealloc_count) {
1210 /* Some of preallocation blocks were not allocated */
1211 #ifdef REISERQUOTA_DEBUG
1212 reiserfs_debug(s, REISERFS_DEBUG_CODE,
1213 "reiserquota: freeing (failed prealloc) %d blocks id=%u",
1214 amount_needed + hint->prealloc_size -
1215 nr_allocated -
1216 REISERFS_I(hint->inode)->i_prealloc_count,
1217 hint->inode->i_uid);
1218 #endif
1219 dquot_free_block_nodirty(hint->inode, amount_needed +
1220 hint->prealloc_size - nr_allocated -
1221 REISERFS_I(hint->inode)->
1222 i_prealloc_count);
1223 }
1224
1225 return CARRY_ON;
1226 }
1227
1228 /* grab new blocknrs from preallocated list */
1229 /* return amount still needed after using them */
1230 static int use_preallocated_list_if_available(reiserfs_blocknr_hint_t * hint,
1231 b_blocknr_t * new_blocknrs,
1232 int amount_needed)
1233 {
1234 struct inode *inode = hint->inode;
1235
1236 if (REISERFS_I(inode)->i_prealloc_count > 0) {
1237 while (amount_needed) {
1238
1239 *new_blocknrs++ = REISERFS_I(inode)->i_prealloc_block++;
1240 REISERFS_I(inode)->i_prealloc_count--;
1241
1242 amount_needed--;
1243
1244 if (REISERFS_I(inode)->i_prealloc_count <= 0) {
1245 list_del(&REISERFS_I(inode)->i_prealloc_list);
1246 break;
1247 }
1248 }
1249 }
1250 /* return amount still needed after using preallocated blocks */
1251 return amount_needed;
1252 }
1253
1254 int 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
1255 already reserved */ )
1256 {
1257 int initial_amount_needed = amount_needed;
1258 int ret;
1259 struct super_block *s = hint->th->t_super;
1260
1261 /* Check if there is enough space, taking into account reserved space */
1262 if (SB_FREE_BLOCKS(s) - REISERFS_SB(s)->reserved_blocks <
1263 amount_needed - reserved_by_us)
1264 return NO_DISK_SPACE;
1265 /* should this be if !hint->inode && hint->preallocate? */
1266 /* do you mean hint->formatted_node can be removed ? - Zam */
1267 /* hint->formatted_node cannot be removed because we try to access
1268 inode information here, and there is often no inode assotiated with
1269 metadata allocations - green */
1270
1271 if (!hint->formatted_node && hint->preallocate) {
1272 amount_needed = use_preallocated_list_if_available
1273 (hint, new_blocknrs, amount_needed);
1274 if (amount_needed == 0) /* all blocknrs we need we got from
1275 prealloc. list */
1276 return CARRY_ON;
1277 new_blocknrs += (initial_amount_needed - amount_needed);
1278 }
1279
1280 /* find search start and save it in hint structure */
1281 determine_search_start(hint, amount_needed);
1282 if (hint->search_start >= SB_BLOCK_COUNT(s))
1283 hint->search_start = SB_BLOCK_COUNT(s) - 1;
1284
1285 /* allocation itself; fill new_blocknrs and preallocation arrays */
1286 ret = blocknrs_and_prealloc_arrays_from_search_start
1287 (hint, new_blocknrs, amount_needed);
1288
1289 /* we used prealloc. list to fill (partially) new_blocknrs array. If final allocation fails we
1290 * need to return blocks back to prealloc. list or just free them. -- Zam (I chose second
1291 * variant) */
1292
1293 if (ret != CARRY_ON) {
1294 while (amount_needed++ < initial_amount_needed) {
1295 reiserfs_free_block(hint->th, hint->inode,
1296 *(--new_blocknrs), 1);
1297 }
1298 }
1299 return ret;
1300 }
1301
1302 void reiserfs_cache_bitmap_metadata(struct super_block *sb,
1303 struct buffer_head *bh,
1304 struct reiserfs_bitmap_info *info)
1305 {
1306 unsigned long *cur = (unsigned long *)(bh->b_data + bh->b_size);
1307
1308 /* The first bit must ALWAYS be 1 */
1309 if (!reiserfs_test_le_bit(0, (unsigned long *)bh->b_data))
1310 reiserfs_error(sb, "reiserfs-2025", "bitmap block %lu is "
1311 "corrupted: first bit must be 1", bh->b_blocknr);
1312
1313 info->free_count = 0;
1314
1315 while (--cur >= (unsigned long *)bh->b_data) {
1316 /* 0 and ~0 are special, we can optimize for them */
1317 if (*cur == 0)
1318 info->free_count += BITS_PER_LONG;
1319 else if (*cur != ~0L) /* A mix, investigate */
1320 info->free_count += BITS_PER_LONG - hweight_long(*cur);
1321 }
1322 }
1323
1324 struct buffer_head *reiserfs_read_bitmap_block(struct super_block *sb,
1325 unsigned int bitmap)
1326 {
1327 b_blocknr_t block = (sb->s_blocksize << 3) * bitmap;
1328 struct reiserfs_bitmap_info *info = SB_AP_BITMAP(sb) + bitmap;
1329 struct buffer_head *bh;
1330
1331 /* Way old format filesystems had the bitmaps packed up front.
1332 * I doubt there are any of these left, but just in case... */
1333 if (unlikely(test_bit(REISERFS_OLD_FORMAT,
1334 &(REISERFS_SB(sb)->s_properties))))
1335 block = REISERFS_SB(sb)->s_sbh->b_blocknr + 1 + bitmap;
1336 else if (bitmap == 0)
1337 block = (REISERFS_DISK_OFFSET_IN_BYTES >> sb->s_blocksize_bits) + 1;
1338
1339 reiserfs_write_unlock(sb);
1340 bh = sb_bread(sb, block);
1341 reiserfs_write_lock(sb);
1342 if (bh == NULL)
1343 reiserfs_warning(sb, "sh-2029: %s: bitmap block (#%u) "
1344 "reading failed", __func__, block);
1345 else {
1346 if (buffer_locked(bh)) {
1347 PROC_INFO_INC(sb, scan_bitmap.wait);
1348 reiserfs_write_unlock(sb);
1349 __wait_on_buffer(bh);
1350 reiserfs_write_lock(sb);
1351 }
1352 BUG_ON(!buffer_uptodate(bh));
1353 BUG_ON(atomic_read(&bh->b_count) == 0);
1354
1355 if (info->free_count == UINT_MAX)
1356 reiserfs_cache_bitmap_metadata(sb, bh, info);
1357 }
1358
1359 return bh;
1360 }
1361
1362 int reiserfs_init_bitmap_cache(struct super_block *sb)
1363 {
1364 struct reiserfs_bitmap_info *bitmap;
1365 unsigned int bmap_nr = reiserfs_bmap_count(sb);
1366
1367 bitmap = vmalloc(sizeof(*bitmap) * bmap_nr);
1368 if (bitmap == NULL)
1369 return -ENOMEM;
1370
1371 memset(bitmap, 0xff, sizeof(*bitmap) * bmap_nr);
1372
1373 SB_AP_BITMAP(sb) = bitmap;
1374
1375 return 0;
1376 }
1377
1378 void reiserfs_free_bitmap_cache(struct super_block *sb)
1379 {
1380 if (SB_AP_BITMAP(sb)) {
1381 vfree(SB_AP_BITMAP(sb));
1382 SB_AP_BITMAP(sb) = NULL;
1383 }
1384 }