revoke.c 20 KB

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  1. /*
  2. * linux/fs/revoke.c
  3. *
  4. * Written by Stephen C. Tweedie <sct@redhat.com>, 2000
  5. *
  6. * Copyright 2000 Red Hat corp --- All Rights Reserved
  7. *
  8. * This file is part of the Linux kernel and is made available under
  9. * the terms of the GNU General Public License, version 2, or at your
  10. * option, any later version, incorporated herein by reference.
  11. *
  12. * Journal revoke routines for the generic filesystem journaling code;
  13. * part of the ext2fs journaling system.
  14. *
  15. * Revoke is the mechanism used to prevent old log records for deleted
  16. * metadata from being replayed on top of newer data using the same
  17. * blocks. The revoke mechanism is used in two separate places:
  18. *
  19. * + Commit: during commit we write the entire list of the current
  20. * transaction's revoked blocks to the journal
  21. *
  22. * + Recovery: during recovery we record the transaction ID of all
  23. * revoked blocks. If there are multiple revoke records in the log
  24. * for a single block, only the last one counts, and if there is a log
  25. * entry for a block beyond the last revoke, then that log entry still
  26. * gets replayed.
  27. *
  28. * We can get interactions between revokes and new log data within a
  29. * single transaction:
  30. *
  31. * Block is revoked and then journaled:
  32. * The desired end result is the journaling of the new block, so we
  33. * cancel the revoke before the transaction commits.
  34. *
  35. * Block is journaled and then revoked:
  36. * The revoke must take precedence over the write of the block, so we
  37. * need either to cancel the journal entry or to write the revoke
  38. * later in the log than the log block. In this case, we choose the
  39. * latter: journaling a block cancels any revoke record for that block
  40. * in the current transaction, so any revoke for that block in the
  41. * transaction must have happened after the block was journaled and so
  42. * the revoke must take precedence.
  43. *
  44. * Block is revoked and then written as data:
  45. * The data write is allowed to succeed, but the revoke is _not_
  46. * cancelled. We still need to prevent old log records from
  47. * overwriting the new data. We don't even need to clear the revoke
  48. * bit here.
  49. *
  50. * Revoke information on buffers is a tri-state value:
  51. *
  52. * RevokeValid clear: no cached revoke status, need to look it up
  53. * RevokeValid set, Revoked clear:
  54. * buffer has not been revoked, and cancel_revoke
  55. * need do nothing.
  56. * RevokeValid set, Revoked set:
  57. * buffer has been revoked.
  58. */
  59. #ifndef __KERNEL__
  60. #include "jfs_user.h"
  61. #else
  62. #include <linux/time.h>
  63. #include <linux/fs.h>
  64. #include <linux/jbd.h>
  65. #include <linux/errno.h>
  66. #include <linux/slab.h>
  67. #include <linux/list.h>
  68. #include <linux/smp_lock.h>
  69. #include <linux/init.h>
  70. #endif
  71. static struct kmem_cache *revoke_record_cache;
  72. static struct kmem_cache *revoke_table_cache;
  73. /* Each revoke record represents one single revoked block. During
  74. journal replay, this involves recording the transaction ID of the
  75. last transaction to revoke this block. */
  76. struct jbd_revoke_record_s
  77. {
  78. struct list_head hash;
  79. tid_t sequence; /* Used for recovery only */
  80. unsigned long blocknr;
  81. };
  82. /* The revoke table is just a simple hash table of revoke records. */
  83. struct jbd_revoke_table_s
  84. {
  85. /* It is conceivable that we might want a larger hash table
  86. * for recovery. Must be a power of two. */
  87. int hash_size;
  88. int hash_shift;
  89. struct list_head *hash_table;
  90. };
  91. #ifdef __KERNEL__
  92. static void write_one_revoke_record(journal_t *, transaction_t *,
  93. struct journal_head **, int *,
  94. struct jbd_revoke_record_s *);
  95. static void flush_descriptor(journal_t *, struct journal_head *, int);
  96. #endif
  97. /* Utility functions to maintain the revoke table */
  98. /* Borrowed from buffer.c: this is a tried and tested block hash function */
  99. static inline int hash(journal_t *journal, unsigned long block)
  100. {
  101. struct jbd_revoke_table_s *table = journal->j_revoke;
  102. int hash_shift = table->hash_shift;
  103. return ((block << (hash_shift - 6)) ^
  104. (block >> 13) ^
  105. (block << (hash_shift - 12))) & (table->hash_size - 1);
  106. }
  107. static int insert_revoke_hash(journal_t *journal, unsigned long blocknr,
  108. tid_t seq)
  109. {
  110. struct list_head *hash_list;
  111. struct jbd_revoke_record_s *record;
  112. repeat:
  113. record = kmem_cache_alloc(revoke_record_cache, GFP_NOFS);
  114. if (!record)
  115. goto oom;
  116. record->sequence = seq;
  117. record->blocknr = blocknr;
  118. hash_list = &journal->j_revoke->hash_table[hash(journal, blocknr)];
  119. spin_lock(&journal->j_revoke_lock);
  120. list_add(&record->hash, hash_list);
  121. spin_unlock(&journal->j_revoke_lock);
  122. return 0;
  123. oom:
  124. if (!journal_oom_retry)
  125. return -ENOMEM;
  126. jbd_debug(1, "ENOMEM in %s, retrying\n", __FUNCTION__);
  127. yield();
  128. goto repeat;
  129. }
  130. /* Find a revoke record in the journal's hash table. */
  131. static struct jbd_revoke_record_s *find_revoke_record(journal_t *journal,
  132. unsigned long blocknr)
  133. {
  134. struct list_head *hash_list;
  135. struct jbd_revoke_record_s *record;
  136. hash_list = &journal->j_revoke->hash_table[hash(journal, blocknr)];
  137. spin_lock(&journal->j_revoke_lock);
  138. record = (struct jbd_revoke_record_s *) hash_list->next;
  139. while (&(record->hash) != hash_list) {
  140. if (record->blocknr == blocknr) {
  141. spin_unlock(&journal->j_revoke_lock);
  142. return record;
  143. }
  144. record = (struct jbd_revoke_record_s *) record->hash.next;
  145. }
  146. spin_unlock(&journal->j_revoke_lock);
  147. return NULL;
  148. }
  149. int __init journal_init_revoke_caches(void)
  150. {
  151. revoke_record_cache = kmem_cache_create("revoke_record",
  152. sizeof(struct jbd_revoke_record_s),
  153. 0, SLAB_HWCACHE_ALIGN, NULL, NULL);
  154. if (revoke_record_cache == 0)
  155. return -ENOMEM;
  156. revoke_table_cache = kmem_cache_create("revoke_table",
  157. sizeof(struct jbd_revoke_table_s),
  158. 0, 0, NULL, NULL);
  159. if (revoke_table_cache == 0) {
  160. kmem_cache_destroy(revoke_record_cache);
  161. revoke_record_cache = NULL;
  162. return -ENOMEM;
  163. }
  164. return 0;
  165. }
  166. void journal_destroy_revoke_caches(void)
  167. {
  168. kmem_cache_destroy(revoke_record_cache);
  169. revoke_record_cache = NULL;
  170. kmem_cache_destroy(revoke_table_cache);
  171. revoke_table_cache = NULL;
  172. }
  173. /* Initialise the revoke table for a given journal to a given size. */
  174. int journal_init_revoke(journal_t *journal, int hash_size)
  175. {
  176. int shift, tmp;
  177. J_ASSERT (journal->j_revoke_table[0] == NULL);
  178. shift = 0;
  179. tmp = hash_size;
  180. while((tmp >>= 1UL) != 0UL)
  181. shift++;
  182. journal->j_revoke_table[0] = kmem_cache_alloc(revoke_table_cache, GFP_KERNEL);
  183. if (!journal->j_revoke_table[0])
  184. return -ENOMEM;
  185. journal->j_revoke = journal->j_revoke_table[0];
  186. /* Check that the hash_size is a power of two */
  187. J_ASSERT ((hash_size & (hash_size-1)) == 0);
  188. journal->j_revoke->hash_size = hash_size;
  189. journal->j_revoke->hash_shift = shift;
  190. journal->j_revoke->hash_table =
  191. kmalloc(hash_size * sizeof(struct list_head), GFP_KERNEL);
  192. if (!journal->j_revoke->hash_table) {
  193. kmem_cache_free(revoke_table_cache, journal->j_revoke_table[0]);
  194. journal->j_revoke = NULL;
  195. return -ENOMEM;
  196. }
  197. for (tmp = 0; tmp < hash_size; tmp++)
  198. INIT_LIST_HEAD(&journal->j_revoke->hash_table[tmp]);
  199. journal->j_revoke_table[1] = kmem_cache_alloc(revoke_table_cache, GFP_KERNEL);
  200. if (!journal->j_revoke_table[1]) {
  201. kfree(journal->j_revoke_table[0]->hash_table);
  202. kmem_cache_free(revoke_table_cache, journal->j_revoke_table[0]);
  203. return -ENOMEM;
  204. }
  205. journal->j_revoke = journal->j_revoke_table[1];
  206. /* Check that the hash_size is a power of two */
  207. J_ASSERT ((hash_size & (hash_size-1)) == 0);
  208. journal->j_revoke->hash_size = hash_size;
  209. journal->j_revoke->hash_shift = shift;
  210. journal->j_revoke->hash_table =
  211. kmalloc(hash_size * sizeof(struct list_head), GFP_KERNEL);
  212. if (!journal->j_revoke->hash_table) {
  213. kfree(journal->j_revoke_table[0]->hash_table);
  214. kmem_cache_free(revoke_table_cache, journal->j_revoke_table[0]);
  215. kmem_cache_free(revoke_table_cache, journal->j_revoke_table[1]);
  216. journal->j_revoke = NULL;
  217. return -ENOMEM;
  218. }
  219. for (tmp = 0; tmp < hash_size; tmp++)
  220. INIT_LIST_HEAD(&journal->j_revoke->hash_table[tmp]);
  221. spin_lock_init(&journal->j_revoke_lock);
  222. return 0;
  223. }
  224. /* Destoy a journal's revoke table. The table must already be empty! */
  225. void journal_destroy_revoke(journal_t *journal)
  226. {
  227. struct jbd_revoke_table_s *table;
  228. struct list_head *hash_list;
  229. int i;
  230. table = journal->j_revoke_table[0];
  231. if (!table)
  232. return;
  233. for (i=0; i<table->hash_size; i++) {
  234. hash_list = &table->hash_table[i];
  235. J_ASSERT (list_empty(hash_list));
  236. }
  237. kfree(table->hash_table);
  238. kmem_cache_free(revoke_table_cache, table);
  239. journal->j_revoke = NULL;
  240. table = journal->j_revoke_table[1];
  241. if (!table)
  242. return;
  243. for (i=0; i<table->hash_size; i++) {
  244. hash_list = &table->hash_table[i];
  245. J_ASSERT (list_empty(hash_list));
  246. }
  247. kfree(table->hash_table);
  248. kmem_cache_free(revoke_table_cache, table);
  249. journal->j_revoke = NULL;
  250. }
  251. #ifdef __KERNEL__
  252. /*
  253. * journal_revoke: revoke a given buffer_head from the journal. This
  254. * prevents the block from being replayed during recovery if we take a
  255. * crash after this current transaction commits. Any subsequent
  256. * metadata writes of the buffer in this transaction cancel the
  257. * revoke.
  258. *
  259. * Note that this call may block --- it is up to the caller to make
  260. * sure that there are no further calls to journal_write_metadata
  261. * before the revoke is complete. In ext3, this implies calling the
  262. * revoke before clearing the block bitmap when we are deleting
  263. * metadata.
  264. *
  265. * Revoke performs a journal_forget on any buffer_head passed in as a
  266. * parameter, but does _not_ forget the buffer_head if the bh was only
  267. * found implicitly.
  268. *
  269. * bh_in may not be a journalled buffer - it may have come off
  270. * the hash tables without an attached journal_head.
  271. *
  272. * If bh_in is non-zero, journal_revoke() will decrement its b_count
  273. * by one.
  274. */
  275. int journal_revoke(handle_t *handle, unsigned long blocknr,
  276. struct buffer_head *bh_in)
  277. {
  278. struct buffer_head *bh = NULL;
  279. journal_t *journal;
  280. struct block_device *bdev;
  281. int err;
  282. might_sleep();
  283. if (bh_in)
  284. BUFFER_TRACE(bh_in, "enter");
  285. journal = handle->h_transaction->t_journal;
  286. if (!journal_set_features(journal, 0, 0, JFS_FEATURE_INCOMPAT_REVOKE)){
  287. J_ASSERT (!"Cannot set revoke feature!");
  288. return -EINVAL;
  289. }
  290. bdev = journal->j_fs_dev;
  291. bh = bh_in;
  292. if (!bh) {
  293. bh = __find_get_block(bdev, blocknr, journal->j_blocksize);
  294. if (bh)
  295. BUFFER_TRACE(bh, "found on hash");
  296. }
  297. #ifdef JBD_EXPENSIVE_CHECKING
  298. else {
  299. struct buffer_head *bh2;
  300. /* If there is a different buffer_head lying around in
  301. * memory anywhere... */
  302. bh2 = __find_get_block(bdev, blocknr, journal->j_blocksize);
  303. if (bh2) {
  304. /* ... and it has RevokeValid status... */
  305. if (bh2 != bh && buffer_revokevalid(bh2))
  306. /* ...then it better be revoked too,
  307. * since it's illegal to create a revoke
  308. * record against a buffer_head which is
  309. * not marked revoked --- that would
  310. * risk missing a subsequent revoke
  311. * cancel. */
  312. J_ASSERT_BH(bh2, buffer_revoked(bh2));
  313. put_bh(bh2);
  314. }
  315. }
  316. #endif
  317. /* We really ought not ever to revoke twice in a row without
  318. first having the revoke cancelled: it's illegal to free a
  319. block twice without allocating it in between! */
  320. if (bh) {
  321. if (!J_EXPECT_BH(bh, !buffer_revoked(bh),
  322. "inconsistent data on disk")) {
  323. if (!bh_in)
  324. brelse(bh);
  325. return -EIO;
  326. }
  327. set_buffer_revoked(bh);
  328. set_buffer_revokevalid(bh);
  329. if (bh_in) {
  330. BUFFER_TRACE(bh_in, "call journal_forget");
  331. journal_forget(handle, bh_in);
  332. } else {
  333. BUFFER_TRACE(bh, "call brelse");
  334. __brelse(bh);
  335. }
  336. }
  337. jbd_debug(2, "insert revoke for block %lu, bh_in=%p\n", blocknr, bh_in);
  338. err = insert_revoke_hash(journal, blocknr,
  339. handle->h_transaction->t_tid);
  340. BUFFER_TRACE(bh_in, "exit");
  341. return err;
  342. }
  343. /*
  344. * Cancel an outstanding revoke. For use only internally by the
  345. * journaling code (called from journal_get_write_access).
  346. *
  347. * We trust buffer_revoked() on the buffer if the buffer is already
  348. * being journaled: if there is no revoke pending on the buffer, then we
  349. * don't do anything here.
  350. *
  351. * This would break if it were possible for a buffer to be revoked and
  352. * discarded, and then reallocated within the same transaction. In such
  353. * a case we would have lost the revoked bit, but when we arrived here
  354. * the second time we would still have a pending revoke to cancel. So,
  355. * do not trust the Revoked bit on buffers unless RevokeValid is also
  356. * set.
  357. *
  358. * The caller must have the journal locked.
  359. */
  360. int journal_cancel_revoke(handle_t *handle, struct journal_head *jh)
  361. {
  362. struct jbd_revoke_record_s *record;
  363. journal_t *journal = handle->h_transaction->t_journal;
  364. int need_cancel;
  365. int did_revoke = 0; /* akpm: debug */
  366. struct buffer_head *bh = jh2bh(jh);
  367. jbd_debug(4, "journal_head %p, cancelling revoke\n", jh);
  368. /* Is the existing Revoke bit valid? If so, we trust it, and
  369. * only perform the full cancel if the revoke bit is set. If
  370. * not, we can't trust the revoke bit, and we need to do the
  371. * full search for a revoke record. */
  372. if (test_set_buffer_revokevalid(bh)) {
  373. need_cancel = test_clear_buffer_revoked(bh);
  374. } else {
  375. need_cancel = 1;
  376. clear_buffer_revoked(bh);
  377. }
  378. if (need_cancel) {
  379. record = find_revoke_record(journal, bh->b_blocknr);
  380. if (record) {
  381. jbd_debug(4, "cancelled existing revoke on "
  382. "blocknr %llu\n", (unsigned long long)bh->b_blocknr);
  383. spin_lock(&journal->j_revoke_lock);
  384. list_del(&record->hash);
  385. spin_unlock(&journal->j_revoke_lock);
  386. kmem_cache_free(revoke_record_cache, record);
  387. did_revoke = 1;
  388. }
  389. }
  390. #ifdef JBD_EXPENSIVE_CHECKING
  391. /* There better not be one left behind by now! */
  392. record = find_revoke_record(journal, bh->b_blocknr);
  393. J_ASSERT_JH(jh, record == NULL);
  394. #endif
  395. /* Finally, have we just cleared revoke on an unhashed
  396. * buffer_head? If so, we'd better make sure we clear the
  397. * revoked status on any hashed alias too, otherwise the revoke
  398. * state machine will get very upset later on. */
  399. if (need_cancel) {
  400. struct buffer_head *bh2;
  401. bh2 = __find_get_block(bh->b_bdev, bh->b_blocknr, bh->b_size);
  402. if (bh2) {
  403. if (bh2 != bh)
  404. clear_buffer_revoked(bh2);
  405. __brelse(bh2);
  406. }
  407. }
  408. return did_revoke;
  409. }
  410. /* journal_switch_revoke table select j_revoke for next transaction
  411. * we do not want to suspend any processing until all revokes are
  412. * written -bzzz
  413. */
  414. void journal_switch_revoke_table(journal_t *journal)
  415. {
  416. int i;
  417. if (journal->j_revoke == journal->j_revoke_table[0])
  418. journal->j_revoke = journal->j_revoke_table[1];
  419. else
  420. journal->j_revoke = journal->j_revoke_table[0];
  421. for (i = 0; i < journal->j_revoke->hash_size; i++)
  422. INIT_LIST_HEAD(&journal->j_revoke->hash_table[i]);
  423. }
  424. /*
  425. * Write revoke records to the journal for all entries in the current
  426. * revoke hash, deleting the entries as we go.
  427. *
  428. * Called with the journal lock held.
  429. */
  430. void journal_write_revoke_records(journal_t *journal,
  431. transaction_t *transaction)
  432. {
  433. struct journal_head *descriptor;
  434. struct jbd_revoke_record_s *record;
  435. struct jbd_revoke_table_s *revoke;
  436. struct list_head *hash_list;
  437. int i, offset, count;
  438. descriptor = NULL;
  439. offset = 0;
  440. count = 0;
  441. /* select revoke table for committing transaction */
  442. revoke = journal->j_revoke == journal->j_revoke_table[0] ?
  443. journal->j_revoke_table[1] : journal->j_revoke_table[0];
  444. for (i = 0; i < revoke->hash_size; i++) {
  445. hash_list = &revoke->hash_table[i];
  446. while (!list_empty(hash_list)) {
  447. record = (struct jbd_revoke_record_s *)
  448. hash_list->next;
  449. write_one_revoke_record(journal, transaction,
  450. &descriptor, &offset,
  451. record);
  452. count++;
  453. list_del(&record->hash);
  454. kmem_cache_free(revoke_record_cache, record);
  455. }
  456. }
  457. if (descriptor)
  458. flush_descriptor(journal, descriptor, offset);
  459. jbd_debug(1, "Wrote %d revoke records\n", count);
  460. }
  461. /*
  462. * Write out one revoke record. We need to create a new descriptor
  463. * block if the old one is full or if we have not already created one.
  464. */
  465. static void write_one_revoke_record(journal_t *journal,
  466. transaction_t *transaction,
  467. struct journal_head **descriptorp,
  468. int *offsetp,
  469. struct jbd_revoke_record_s *record)
  470. {
  471. struct journal_head *descriptor;
  472. int offset;
  473. journal_header_t *header;
  474. /* If we are already aborting, this all becomes a noop. We
  475. still need to go round the loop in
  476. journal_write_revoke_records in order to free all of the
  477. revoke records: only the IO to the journal is omitted. */
  478. if (is_journal_aborted(journal))
  479. return;
  480. descriptor = *descriptorp;
  481. offset = *offsetp;
  482. /* Make sure we have a descriptor with space left for the record */
  483. if (descriptor) {
  484. if (offset == journal->j_blocksize) {
  485. flush_descriptor(journal, descriptor, offset);
  486. descriptor = NULL;
  487. }
  488. }
  489. if (!descriptor) {
  490. descriptor = journal_get_descriptor_buffer(journal);
  491. if (!descriptor)
  492. return;
  493. header = (journal_header_t *) &jh2bh(descriptor)->b_data[0];
  494. header->h_magic = cpu_to_be32(JFS_MAGIC_NUMBER);
  495. header->h_blocktype = cpu_to_be32(JFS_REVOKE_BLOCK);
  496. header->h_sequence = cpu_to_be32(transaction->t_tid);
  497. /* Record it so that we can wait for IO completion later */
  498. JBUFFER_TRACE(descriptor, "file as BJ_LogCtl");
  499. journal_file_buffer(descriptor, transaction, BJ_LogCtl);
  500. offset = sizeof(journal_revoke_header_t);
  501. *descriptorp = descriptor;
  502. }
  503. * ((__be32 *)(&jh2bh(descriptor)->b_data[offset])) =
  504. cpu_to_be32(record->blocknr);
  505. offset += 4;
  506. *offsetp = offset;
  507. }
  508. /*
  509. * Flush a revoke descriptor out to the journal. If we are aborting,
  510. * this is a noop; otherwise we are generating a buffer which needs to
  511. * be waited for during commit, so it has to go onto the appropriate
  512. * journal buffer list.
  513. */
  514. static void flush_descriptor(journal_t *journal,
  515. struct journal_head *descriptor,
  516. int offset)
  517. {
  518. journal_revoke_header_t *header;
  519. struct buffer_head *bh = jh2bh(descriptor);
  520. if (is_journal_aborted(journal)) {
  521. put_bh(bh);
  522. return;
  523. }
  524. header = (journal_revoke_header_t *) jh2bh(descriptor)->b_data;
  525. header->r_count = cpu_to_be32(offset);
  526. set_buffer_jwrite(bh);
  527. BUFFER_TRACE(bh, "write");
  528. set_buffer_dirty(bh);
  529. ll_rw_block(SWRITE, 1, &bh);
  530. }
  531. #endif
  532. /*
  533. * Revoke support for recovery.
  534. *
  535. * Recovery needs to be able to:
  536. *
  537. * record all revoke records, including the tid of the latest instance
  538. * of each revoke in the journal
  539. *
  540. * check whether a given block in a given transaction should be replayed
  541. * (ie. has not been revoked by a revoke record in that or a subsequent
  542. * transaction)
  543. *
  544. * empty the revoke table after recovery.
  545. */
  546. /*
  547. * First, setting revoke records. We create a new revoke record for
  548. * every block ever revoked in the log as we scan it for recovery, and
  549. * we update the existing records if we find multiple revokes for a
  550. * single block.
  551. */
  552. int journal_set_revoke(journal_t *journal,
  553. unsigned long blocknr,
  554. tid_t sequence)
  555. {
  556. struct jbd_revoke_record_s *record;
  557. record = find_revoke_record(journal, blocknr);
  558. if (record) {
  559. /* If we have multiple occurrences, only record the
  560. * latest sequence number in the hashed record */
  561. if (tid_gt(sequence, record->sequence))
  562. record->sequence = sequence;
  563. return 0;
  564. }
  565. return insert_revoke_hash(journal, blocknr, sequence);
  566. }
  567. /*
  568. * Test revoke records. For a given block referenced in the log, has
  569. * that block been revoked? A revoke record with a given transaction
  570. * sequence number revokes all blocks in that transaction and earlier
  571. * ones, but later transactions still need replayed.
  572. */
  573. int journal_test_revoke(journal_t *journal,
  574. unsigned long blocknr,
  575. tid_t sequence)
  576. {
  577. struct jbd_revoke_record_s *record;
  578. record = find_revoke_record(journal, blocknr);
  579. if (!record)
  580. return 0;
  581. if (tid_gt(sequence, record->sequence))
  582. return 0;
  583. return 1;
  584. }
  585. /*
  586. * Finally, once recovery is over, we need to clear the revoke table so
  587. * that it can be reused by the running filesystem.
  588. */
  589. void journal_clear_revoke(journal_t *journal)
  590. {
  591. int i;
  592. struct list_head *hash_list;
  593. struct jbd_revoke_record_s *record;
  594. struct jbd_revoke_table_s *revoke;
  595. revoke = journal->j_revoke;
  596. for (i = 0; i < revoke->hash_size; i++) {
  597. hash_list = &revoke->hash_table[i];
  598. while (!list_empty(hash_list)) {
  599. record = (struct jbd_revoke_record_s*) hash_list->next;
  600. list_del(&record->hash);
  601. kmem_cache_free(revoke_record_cache, record);
  602. }
  603. }
  604. }