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83#ifndef __KERNEL__
84#include "jfs_user.h"
85#else
86#include <linux/time.h>
87#include <linux/fs.h>
88#include <linux/jbd.h>
89#include <linux/errno.h>
90#include <linux/slab.h>
91#include <linux/list.h>
92#include <linux/init.h>
93#include <linux/bio.h>
94#endif
95#include <linux/log2.h>
96
97static struct kmem_cache *revoke_record_cache;
98static struct kmem_cache *revoke_table_cache;
99
100
101
102
103
104struct jbd_revoke_record_s
105{
106 struct list_head hash;
107 tid_t sequence;
108 unsigned int blocknr;
109};
110
111
112
113struct jbd_revoke_table_s
114{
115
116
117 int hash_size;
118 int hash_shift;
119 struct list_head *hash_table;
120};
121
122
123#ifdef __KERNEL__
124static void write_one_revoke_record(journal_t *, transaction_t *,
125 struct journal_head **, int *,
126 struct jbd_revoke_record_s *, int);
127static void flush_descriptor(journal_t *, struct journal_head *, int, int);
128#endif
129
130
131
132
133static inline int hash(journal_t *journal, unsigned int block)
134{
135 struct jbd_revoke_table_s *table = journal->j_revoke;
136 int hash_shift = table->hash_shift;
137
138 return ((block << (hash_shift - 6)) ^
139 (block >> 13) ^
140 (block << (hash_shift - 12))) & (table->hash_size - 1);
141}
142
143static int insert_revoke_hash(journal_t *journal, unsigned int blocknr,
144 tid_t seq)
145{
146 struct list_head *hash_list;
147 struct jbd_revoke_record_s *record;
148
149repeat:
150 record = kmem_cache_alloc(revoke_record_cache, GFP_NOFS);
151 if (!record)
152 goto oom;
153
154 record->sequence = seq;
155 record->blocknr = blocknr;
156 hash_list = &journal->j_revoke->hash_table[hash(journal, blocknr)];
157 spin_lock(&journal->j_revoke_lock);
158 list_add(&record->hash, hash_list);
159 spin_unlock(&journal->j_revoke_lock);
160 return 0;
161
162oom:
163 if (!journal_oom_retry)
164 return -ENOMEM;
165 jbd_debug(1, "ENOMEM in %s, retrying\n", __func__);
166 yield();
167 goto repeat;
168}
169
170
171
172static struct jbd_revoke_record_s *find_revoke_record(journal_t *journal,
173 unsigned int blocknr)
174{
175 struct list_head *hash_list;
176 struct jbd_revoke_record_s *record;
177
178 hash_list = &journal->j_revoke->hash_table[hash(journal, blocknr)];
179
180 spin_lock(&journal->j_revoke_lock);
181 record = (struct jbd_revoke_record_s *) hash_list->next;
182 while (&(record->hash) != hash_list) {
183 if (record->blocknr == blocknr) {
184 spin_unlock(&journal->j_revoke_lock);
185 return record;
186 }
187 record = (struct jbd_revoke_record_s *) record->hash.next;
188 }
189 spin_unlock(&journal->j_revoke_lock);
190 return NULL;
191}
192
193void journal_destroy_revoke_caches(void)
194{
195 if (revoke_record_cache) {
196 kmem_cache_destroy(revoke_record_cache);
197 revoke_record_cache = NULL;
198 }
199 if (revoke_table_cache) {
200 kmem_cache_destroy(revoke_table_cache);
201 revoke_table_cache = NULL;
202 }
203}
204
205int __init journal_init_revoke_caches(void)
206{
207 J_ASSERT(!revoke_record_cache);
208 J_ASSERT(!revoke_table_cache);
209
210 revoke_record_cache = kmem_cache_create("revoke_record",
211 sizeof(struct jbd_revoke_record_s),
212 0,
213 SLAB_HWCACHE_ALIGN|SLAB_TEMPORARY,
214 NULL);
215 if (!revoke_record_cache)
216 goto record_cache_failure;
217
218 revoke_table_cache = kmem_cache_create("revoke_table",
219 sizeof(struct jbd_revoke_table_s),
220 0, SLAB_TEMPORARY, NULL);
221 if (!revoke_table_cache)
222 goto table_cache_failure;
223
224 return 0;
225
226table_cache_failure:
227 journal_destroy_revoke_caches();
228record_cache_failure:
229 return -ENOMEM;
230}
231
232static struct jbd_revoke_table_s *journal_init_revoke_table(int hash_size)
233{
234 int shift = 0;
235 int tmp = hash_size;
236 struct jbd_revoke_table_s *table;
237
238 table = kmem_cache_alloc(revoke_table_cache, GFP_KERNEL);
239 if (!table)
240 goto out;
241
242 while((tmp >>= 1UL) != 0UL)
243 shift++;
244
245 table->hash_size = hash_size;
246 table->hash_shift = shift;
247 table->hash_table =
248 kmalloc(hash_size * sizeof(struct list_head), GFP_KERNEL);
249 if (!table->hash_table) {
250 kmem_cache_free(revoke_table_cache, table);
251 table = NULL;
252 goto out;
253 }
254
255 for (tmp = 0; tmp < hash_size; tmp++)
256 INIT_LIST_HEAD(&table->hash_table[tmp]);
257
258out:
259 return table;
260}
261
262static void journal_destroy_revoke_table(struct jbd_revoke_table_s *table)
263{
264 int i;
265 struct list_head *hash_list;
266
267 for (i = 0; i < table->hash_size; i++) {
268 hash_list = &table->hash_table[i];
269 J_ASSERT(list_empty(hash_list));
270 }
271
272 kfree(table->hash_table);
273 kmem_cache_free(revoke_table_cache, table);
274}
275
276
277int journal_init_revoke(journal_t *journal, int hash_size)
278{
279 J_ASSERT(journal->j_revoke_table[0] == NULL);
280 J_ASSERT(is_power_of_2(hash_size));
281
282 journal->j_revoke_table[0] = journal_init_revoke_table(hash_size);
283 if (!journal->j_revoke_table[0])
284 goto fail0;
285
286 journal->j_revoke_table[1] = journal_init_revoke_table(hash_size);
287 if (!journal->j_revoke_table[1])
288 goto fail1;
289
290 journal->j_revoke = journal->j_revoke_table[1];
291
292 spin_lock_init(&journal->j_revoke_lock);
293
294 return 0;
295
296fail1:
297 journal_destroy_revoke_table(journal->j_revoke_table[0]);
298fail0:
299 return -ENOMEM;
300}
301
302
303void journal_destroy_revoke(journal_t *journal)
304{
305 journal->j_revoke = NULL;
306 if (journal->j_revoke_table[0])
307 journal_destroy_revoke_table(journal->j_revoke_table[0]);
308 if (journal->j_revoke_table[1])
309 journal_destroy_revoke_table(journal->j_revoke_table[1]);
310}
311
312
313#ifdef __KERNEL__
314
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339int journal_revoke(handle_t *handle, unsigned int blocknr,
340 struct buffer_head *bh_in)
341{
342 struct buffer_head *bh = NULL;
343 journal_t *journal;
344 struct block_device *bdev;
345 int err;
346
347 might_sleep();
348 if (bh_in)
349 BUFFER_TRACE(bh_in, "enter");
350
351 journal = handle->h_transaction->t_journal;
352 if (!journal_set_features(journal, 0, 0, JFS_FEATURE_INCOMPAT_REVOKE)){
353 J_ASSERT (!"Cannot set revoke feature!");
354 return -EINVAL;
355 }
356
357 bdev = journal->j_fs_dev;
358 bh = bh_in;
359
360 if (!bh) {
361 bh = __find_get_block(bdev, blocknr, journal->j_blocksize);
362 if (bh)
363 BUFFER_TRACE(bh, "found on hash");
364 }
365#ifdef JBD_EXPENSIVE_CHECKING
366 else {
367 struct buffer_head *bh2;
368
369
370
371 bh2 = __find_get_block(bdev, blocknr, journal->j_blocksize);
372 if (bh2) {
373
374 if (bh2 != bh && buffer_revokevalid(bh2))
375
376
377
378
379
380
381 J_ASSERT_BH(bh2, buffer_revoked(bh2));
382 put_bh(bh2);
383 }
384 }
385#endif
386
387
388
389
390 if (bh) {
391 if (!J_EXPECT_BH(bh, !buffer_revoked(bh),
392 "inconsistent data on disk")) {
393 if (!bh_in)
394 brelse(bh);
395 return -EIO;
396 }
397 set_buffer_revoked(bh);
398 set_buffer_revokevalid(bh);
399 if (bh_in) {
400 BUFFER_TRACE(bh_in, "call journal_forget");
401 journal_forget(handle, bh_in);
402 } else {
403 BUFFER_TRACE(bh, "call brelse");
404 __brelse(bh);
405 }
406 }
407
408 jbd_debug(2, "insert revoke for block %u, bh_in=%p\n", blocknr, bh_in);
409 err = insert_revoke_hash(journal, blocknr,
410 handle->h_transaction->t_tid);
411 BUFFER_TRACE(bh_in, "exit");
412 return err;
413}
414
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430int journal_cancel_revoke(handle_t *handle, struct journal_head *jh)
431{
432 struct jbd_revoke_record_s *record;
433 journal_t *journal = handle->h_transaction->t_journal;
434 int need_cancel;
435 int did_revoke = 0;
436 struct buffer_head *bh = jh2bh(jh);
437
438 jbd_debug(4, "journal_head %p, cancelling revoke\n", jh);
439
440
441
442
443
444 if (test_set_buffer_revokevalid(bh)) {
445 need_cancel = test_clear_buffer_revoked(bh);
446 } else {
447 need_cancel = 1;
448 clear_buffer_revoked(bh);
449 }
450
451 if (need_cancel) {
452 record = find_revoke_record(journal, bh->b_blocknr);
453 if (record) {
454 jbd_debug(4, "cancelled existing revoke on "
455 "blocknr %llu\n", (unsigned long long)bh->b_blocknr);
456 spin_lock(&journal->j_revoke_lock);
457 list_del(&record->hash);
458 spin_unlock(&journal->j_revoke_lock);
459 kmem_cache_free(revoke_record_cache, record);
460 did_revoke = 1;
461 }
462 }
463
464#ifdef JBD_EXPENSIVE_CHECKING
465
466 record = find_revoke_record(journal, bh->b_blocknr);
467 J_ASSERT_JH(jh, record == NULL);
468#endif
469
470
471
472
473
474 if (need_cancel) {
475 struct buffer_head *bh2;
476 bh2 = __find_get_block(bh->b_bdev, bh->b_blocknr, bh->b_size);
477 if (bh2) {
478 if (bh2 != bh)
479 clear_buffer_revoked(bh2);
480 __brelse(bh2);
481 }
482 }
483 return did_revoke;
484}
485
486
487
488
489
490
491void journal_clear_buffer_revoked_flags(journal_t *journal)
492{
493 struct jbd_revoke_table_s *revoke = journal->j_revoke;
494 int i = 0;
495
496 for (i = 0; i < revoke->hash_size; i++) {
497 struct list_head *hash_list;
498 struct list_head *list_entry;
499 hash_list = &revoke->hash_table[i];
500
501 list_for_each(list_entry, hash_list) {
502 struct jbd_revoke_record_s *record;
503 struct buffer_head *bh;
504 record = (struct jbd_revoke_record_s *)list_entry;
505 bh = __find_get_block(journal->j_fs_dev,
506 record->blocknr,
507 journal->j_blocksize);
508 if (bh) {
509 clear_buffer_revoked(bh);
510 __brelse(bh);
511 }
512 }
513 }
514}
515
516
517
518
519
520void journal_switch_revoke_table(journal_t *journal)
521{
522 int i;
523
524 if (journal->j_revoke == journal->j_revoke_table[0])
525 journal->j_revoke = journal->j_revoke_table[1];
526 else
527 journal->j_revoke = journal->j_revoke_table[0];
528
529 for (i = 0; i < journal->j_revoke->hash_size; i++)
530 INIT_LIST_HEAD(&journal->j_revoke->hash_table[i]);
531}
532
533
534
535
536
537void journal_write_revoke_records(journal_t *journal,
538 transaction_t *transaction, int write_op)
539{
540 struct journal_head *descriptor;
541 struct jbd_revoke_record_s *record;
542 struct jbd_revoke_table_s *revoke;
543 struct list_head *hash_list;
544 int i, offset, count;
545
546 descriptor = NULL;
547 offset = 0;
548 count = 0;
549
550
551 revoke = journal->j_revoke == journal->j_revoke_table[0] ?
552 journal->j_revoke_table[1] : journal->j_revoke_table[0];
553
554 for (i = 0; i < revoke->hash_size; i++) {
555 hash_list = &revoke->hash_table[i];
556
557 while (!list_empty(hash_list)) {
558 record = (struct jbd_revoke_record_s *)
559 hash_list->next;
560 write_one_revoke_record(journal, transaction,
561 &descriptor, &offset,
562 record, write_op);
563 count++;
564 list_del(&record->hash);
565 kmem_cache_free(revoke_record_cache, record);
566 }
567 }
568 if (descriptor)
569 flush_descriptor(journal, descriptor, offset, write_op);
570 jbd_debug(1, "Wrote %d revoke records\n", count);
571}
572
573
574
575
576
577
578static void write_one_revoke_record(journal_t *journal,
579 transaction_t *transaction,
580 struct journal_head **descriptorp,
581 int *offsetp,
582 struct jbd_revoke_record_s *record,
583 int write_op)
584{
585 struct journal_head *descriptor;
586 int offset;
587 journal_header_t *header;
588
589
590
591
592
593 if (is_journal_aborted(journal))
594 return;
595
596 descriptor = *descriptorp;
597 offset = *offsetp;
598
599
600 if (descriptor) {
601 if (offset == journal->j_blocksize) {
602 flush_descriptor(journal, descriptor, offset, write_op);
603 descriptor = NULL;
604 }
605 }
606
607 if (!descriptor) {
608 descriptor = journal_get_descriptor_buffer(journal);
609 if (!descriptor)
610 return;
611 header = (journal_header_t *) &jh2bh(descriptor)->b_data[0];
612 header->h_magic = cpu_to_be32(JFS_MAGIC_NUMBER);
613 header->h_blocktype = cpu_to_be32(JFS_REVOKE_BLOCK);
614 header->h_sequence = cpu_to_be32(transaction->t_tid);
615
616
617 JBUFFER_TRACE(descriptor, "file as BJ_LogCtl");
618 journal_file_buffer(descriptor, transaction, BJ_LogCtl);
619
620 offset = sizeof(journal_revoke_header_t);
621 *descriptorp = descriptor;
622 }
623
624 * ((__be32 *)(&jh2bh(descriptor)->b_data[offset])) =
625 cpu_to_be32(record->blocknr);
626 offset += 4;
627 *offsetp = offset;
628}
629
630
631
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635
636
637static void flush_descriptor(journal_t *journal,
638 struct journal_head *descriptor,
639 int offset, int write_op)
640{
641 journal_revoke_header_t *header;
642 struct buffer_head *bh = jh2bh(descriptor);
643
644 if (is_journal_aborted(journal)) {
645 put_bh(bh);
646 return;
647 }
648
649 header = (journal_revoke_header_t *) jh2bh(descriptor)->b_data;
650 header->r_count = cpu_to_be32(offset);
651 set_buffer_jwrite(bh);
652 BUFFER_TRACE(bh, "write");
653 set_buffer_dirty(bh);
654 write_dirty_buffer(bh, write_op);
655}
656#endif
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680int journal_set_revoke(journal_t *journal,
681 unsigned int blocknr,
682 tid_t sequence)
683{
684 struct jbd_revoke_record_s *record;
685
686 record = find_revoke_record(journal, blocknr);
687 if (record) {
688
689
690 if (tid_gt(sequence, record->sequence))
691 record->sequence = sequence;
692 return 0;
693 }
694 return insert_revoke_hash(journal, blocknr, sequence);
695}
696
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703
704int journal_test_revoke(journal_t *journal,
705 unsigned int blocknr,
706 tid_t sequence)
707{
708 struct jbd_revoke_record_s *record;
709
710 record = find_revoke_record(journal, blocknr);
711 if (!record)
712 return 0;
713 if (tid_gt(sequence, record->sequence))
714 return 0;
715 return 1;
716}
717
718
719
720
721
722
723void journal_clear_revoke(journal_t *journal)
724{
725 int i;
726 struct list_head *hash_list;
727 struct jbd_revoke_record_s *record;
728 struct jbd_revoke_table_s *revoke;
729
730 revoke = journal->j_revoke;
731
732 for (i = 0; i < revoke->hash_size; i++) {
733 hash_list = &revoke->hash_table[i];
734 while (!list_empty(hash_list)) {
735 record = (struct jbd_revoke_record_s*) hash_list->next;
736 list_del(&record->hash);
737 kmem_cache_free(revoke_record_cache, record);
738 }
739 }
740}
741