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1da177e4 LT |
1 | /* |
2 | * linux/fs/checkpoint.c | |
3 | * | |
4 | * Written by Stephen C. Tweedie <sct@redhat.com>, 1999 | |
5 | * | |
6 | * Copyright 1999 Red Hat Software --- 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 | * Checkpoint routines for the generic filesystem journaling code. | |
13 | * Part of the ext2fs journaling system. | |
14 | * | |
15 | * Checkpointing is the process of ensuring that a section of the log is | |
16 | * committed fully to disk, so that that portion of the log can be | |
17 | * reused. | |
18 | */ | |
19 | ||
20 | #include <linux/time.h> | |
21 | #include <linux/fs.h> | |
22 | #include <linux/jbd.h> | |
23 | #include <linux/errno.h> | |
24 | #include <linux/slab.h> | |
25 | ||
26 | /* | |
27 | * Unlink a buffer from a transaction. | |
28 | * | |
29 | * Called with j_list_lock held. | |
30 | */ | |
31 | ||
32 | static inline void __buffer_unlink(struct journal_head *jh) | |
33 | { | |
34 | transaction_t *transaction; | |
35 | ||
36 | transaction = jh->b_cp_transaction; | |
37 | jh->b_cp_transaction = NULL; | |
38 | ||
39 | jh->b_cpnext->b_cpprev = jh->b_cpprev; | |
40 | jh->b_cpprev->b_cpnext = jh->b_cpnext; | |
41 | if (transaction->t_checkpoint_list == jh) | |
42 | transaction->t_checkpoint_list = jh->b_cpnext; | |
43 | if (transaction->t_checkpoint_list == jh) | |
44 | transaction->t_checkpoint_list = NULL; | |
45 | } | |
46 | ||
47 | /* | |
48 | * Try to release a checkpointed buffer from its transaction. | |
49 | * Returns 1 if we released it. | |
50 | * Requires j_list_lock | |
51 | * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it | |
52 | */ | |
53 | static int __try_to_free_cp_buf(struct journal_head *jh) | |
54 | { | |
55 | int ret = 0; | |
56 | struct buffer_head *bh = jh2bh(jh); | |
57 | ||
58 | if (jh->b_jlist == BJ_None && !buffer_locked(bh) && !buffer_dirty(bh)) { | |
59 | JBUFFER_TRACE(jh, "remove from checkpoint list"); | |
60 | __journal_remove_checkpoint(jh); | |
61 | jbd_unlock_bh_state(bh); | |
62 | journal_remove_journal_head(bh); | |
63 | BUFFER_TRACE(bh, "release"); | |
64 | __brelse(bh); | |
65 | ret = 1; | |
66 | } else { | |
67 | jbd_unlock_bh_state(bh); | |
68 | } | |
69 | return ret; | |
70 | } | |
71 | ||
72 | /* | |
73 | * __log_wait_for_space: wait until there is space in the journal. | |
74 | * | |
75 | * Called under j-state_lock *only*. It will be unlocked if we have to wait | |
76 | * for a checkpoint to free up some space in the log. | |
77 | */ | |
78 | void __log_wait_for_space(journal_t *journal) | |
79 | { | |
80 | int nblocks; | |
81 | assert_spin_locked(&journal->j_state_lock); | |
82 | ||
83 | nblocks = jbd_space_needed(journal); | |
84 | while (__log_space_left(journal) < nblocks) { | |
85 | if (journal->j_flags & JFS_ABORT) | |
86 | return; | |
87 | spin_unlock(&journal->j_state_lock); | |
88 | down(&journal->j_checkpoint_sem); | |
89 | ||
90 | /* | |
91 | * Test again, another process may have checkpointed while we | |
92 | * were waiting for the checkpoint lock | |
93 | */ | |
94 | spin_lock(&journal->j_state_lock); | |
95 | nblocks = jbd_space_needed(journal); | |
96 | if (__log_space_left(journal) < nblocks) { | |
97 | spin_unlock(&journal->j_state_lock); | |
98 | log_do_checkpoint(journal); | |
99 | spin_lock(&journal->j_state_lock); | |
100 | } | |
101 | up(&journal->j_checkpoint_sem); | |
102 | } | |
103 | } | |
104 | ||
105 | /* | |
106 | * We were unable to perform jbd_trylock_bh_state() inside j_list_lock. | |
107 | * The caller must restart a list walk. Wait for someone else to run | |
108 | * jbd_unlock_bh_state(). | |
109 | */ | |
110 | static void jbd_sync_bh(journal_t *journal, struct buffer_head *bh) | |
111 | { | |
112 | get_bh(bh); | |
113 | spin_unlock(&journal->j_list_lock); | |
114 | jbd_lock_bh_state(bh); | |
115 | jbd_unlock_bh_state(bh); | |
116 | put_bh(bh); | |
117 | } | |
118 | ||
119 | /* | |
120 | * Clean up a transaction's checkpoint list. | |
121 | * | |
122 | * We wait for any pending IO to complete and make sure any clean | |
123 | * buffers are removed from the transaction. | |
124 | * | |
125 | * Return 1 if we performed any actions which might have destroyed the | |
126 | * checkpoint. (journal_remove_checkpoint() deletes the transaction when | |
127 | * the last checkpoint buffer is cleansed) | |
128 | * | |
129 | * Called with j_list_lock held. | |
130 | */ | |
131 | static int __cleanup_transaction(journal_t *journal, transaction_t *transaction) | |
132 | { | |
133 | struct journal_head *jh, *next_jh, *last_jh; | |
134 | struct buffer_head *bh; | |
135 | int ret = 0; | |
136 | ||
137 | assert_spin_locked(&journal->j_list_lock); | |
138 | jh = transaction->t_checkpoint_list; | |
139 | if (!jh) | |
140 | return 0; | |
141 | ||
142 | last_jh = jh->b_cpprev; | |
143 | next_jh = jh; | |
144 | do { | |
145 | jh = next_jh; | |
146 | bh = jh2bh(jh); | |
147 | if (buffer_locked(bh)) { | |
148 | atomic_inc(&bh->b_count); | |
149 | spin_unlock(&journal->j_list_lock); | |
150 | wait_on_buffer(bh); | |
151 | /* the journal_head may have gone by now */ | |
152 | BUFFER_TRACE(bh, "brelse"); | |
153 | __brelse(bh); | |
154 | goto out_return_1; | |
155 | } | |
156 | ||
157 | /* | |
158 | * This is foul | |
159 | */ | |
160 | if (!jbd_trylock_bh_state(bh)) { | |
161 | jbd_sync_bh(journal, bh); | |
162 | goto out_return_1; | |
163 | } | |
164 | ||
165 | if (jh->b_transaction != NULL) { | |
166 | transaction_t *t = jh->b_transaction; | |
167 | tid_t tid = t->t_tid; | |
168 | ||
169 | spin_unlock(&journal->j_list_lock); | |
170 | jbd_unlock_bh_state(bh); | |
171 | log_start_commit(journal, tid); | |
172 | log_wait_commit(journal, tid); | |
173 | goto out_return_1; | |
174 | } | |
175 | ||
176 | /* | |
177 | * AKPM: I think the buffer_jbddirty test is redundant - it | |
178 | * shouldn't have NULL b_transaction? | |
179 | */ | |
180 | next_jh = jh->b_cpnext; | |
181 | if (!buffer_dirty(bh) && !buffer_jbddirty(bh)) { | |
182 | BUFFER_TRACE(bh, "remove from checkpoint"); | |
183 | __journal_remove_checkpoint(jh); | |
184 | jbd_unlock_bh_state(bh); | |
185 | journal_remove_journal_head(bh); | |
186 | __brelse(bh); | |
187 | ret = 1; | |
188 | } else { | |
189 | jbd_unlock_bh_state(bh); | |
190 | } | |
191 | jh = next_jh; | |
192 | } while (jh != last_jh); | |
193 | ||
194 | return ret; | |
195 | out_return_1: | |
196 | spin_lock(&journal->j_list_lock); | |
197 | return 1; | |
198 | } | |
199 | ||
200 | #define NR_BATCH 64 | |
201 | ||
202 | static void | |
203 | __flush_batch(journal_t *journal, struct buffer_head **bhs, int *batch_count) | |
204 | { | |
205 | int i; | |
206 | ||
207 | spin_unlock(&journal->j_list_lock); | |
208 | ll_rw_block(WRITE, *batch_count, bhs); | |
209 | spin_lock(&journal->j_list_lock); | |
210 | for (i = 0; i < *batch_count; i++) { | |
211 | struct buffer_head *bh = bhs[i]; | |
212 | clear_buffer_jwrite(bh); | |
213 | BUFFER_TRACE(bh, "brelse"); | |
214 | __brelse(bh); | |
215 | } | |
216 | *batch_count = 0; | |
217 | } | |
218 | ||
219 | /* | |
220 | * Try to flush one buffer from the checkpoint list to disk. | |
221 | * | |
222 | * Return 1 if something happened which requires us to abort the current | |
223 | * scan of the checkpoint list. | |
224 | * | |
225 | * Called with j_list_lock held. | |
226 | * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it | |
227 | */ | |
228 | static int __flush_buffer(journal_t *journal, struct journal_head *jh, | |
229 | struct buffer_head **bhs, int *batch_count, | |
230 | int *drop_count) | |
231 | { | |
232 | struct buffer_head *bh = jh2bh(jh); | |
233 | int ret = 0; | |
234 | ||
235 | if (buffer_dirty(bh) && !buffer_locked(bh) && jh->b_jlist == BJ_None) { | |
236 | J_ASSERT_JH(jh, jh->b_transaction == NULL); | |
237 | ||
238 | /* | |
239 | * Important: we are about to write the buffer, and | |
240 | * possibly block, while still holding the journal lock. | |
241 | * We cannot afford to let the transaction logic start | |
242 | * messing around with this buffer before we write it to | |
243 | * disk, as that would break recoverability. | |
244 | */ | |
245 | BUFFER_TRACE(bh, "queue"); | |
246 | get_bh(bh); | |
247 | J_ASSERT_BH(bh, !buffer_jwrite(bh)); | |
248 | set_buffer_jwrite(bh); | |
249 | bhs[*batch_count] = bh; | |
250 | jbd_unlock_bh_state(bh); | |
251 | (*batch_count)++; | |
252 | if (*batch_count == NR_BATCH) { | |
253 | __flush_batch(journal, bhs, batch_count); | |
254 | ret = 1; | |
255 | } | |
256 | } else { | |
257 | int last_buffer = 0; | |
258 | if (jh->b_cpnext == jh) { | |
259 | /* We may be about to drop the transaction. Tell the | |
260 | * caller that the lists have changed. | |
261 | */ | |
262 | last_buffer = 1; | |
263 | } | |
264 | if (__try_to_free_cp_buf(jh)) { | |
265 | (*drop_count)++; | |
266 | ret = last_buffer; | |
267 | } | |
268 | } | |
269 | return ret; | |
270 | } | |
271 | ||
272 | /* | |
273 | * Perform an actual checkpoint. We don't write out only enough to | |
274 | * satisfy the current blocked requests: rather we submit a reasonably | |
275 | * sized chunk of the outstanding data to disk at once for | |
276 | * efficiency. __log_wait_for_space() will retry if we didn't free enough. | |
277 | * | |
278 | * However, we _do_ take into account the amount requested so that once | |
279 | * the IO has been queued, we can return as soon as enough of it has | |
280 | * completed to disk. | |
281 | * | |
282 | * The journal should be locked before calling this function. | |
283 | */ | |
284 | int log_do_checkpoint(journal_t *journal) | |
285 | { | |
286 | int result; | |
287 | int batch_count = 0; | |
288 | struct buffer_head *bhs[NR_BATCH]; | |
289 | ||
290 | jbd_debug(1, "Start checkpoint\n"); | |
291 | ||
292 | /* | |
293 | * First thing: if there are any transactions in the log which | |
294 | * don't need checkpointing, just eliminate them from the | |
295 | * journal straight away. | |
296 | */ | |
297 | result = cleanup_journal_tail(journal); | |
298 | jbd_debug(1, "cleanup_journal_tail returned %d\n", result); | |
299 | if (result <= 0) | |
300 | return result; | |
301 | ||
302 | /* | |
303 | * OK, we need to start writing disk blocks. Try to free up a | |
304 | * quarter of the log in a single checkpoint if we can. | |
305 | */ | |
306 | /* | |
307 | * AKPM: check this code. I had a feeling a while back that it | |
308 | * degenerates into a busy loop at unmount time. | |
309 | */ | |
310 | spin_lock(&journal->j_list_lock); | |
311 | while (journal->j_checkpoint_transactions) { | |
312 | transaction_t *transaction; | |
313 | struct journal_head *jh, *last_jh, *next_jh; | |
314 | int drop_count = 0; | |
315 | int cleanup_ret, retry = 0; | |
316 | tid_t this_tid; | |
317 | ||
318 | transaction = journal->j_checkpoint_transactions; | |
319 | this_tid = transaction->t_tid; | |
320 | jh = transaction->t_checkpoint_list; | |
321 | last_jh = jh->b_cpprev; | |
322 | next_jh = jh; | |
323 | do { | |
324 | struct buffer_head *bh; | |
325 | ||
326 | jh = next_jh; | |
327 | next_jh = jh->b_cpnext; | |
328 | bh = jh2bh(jh); | |
329 | if (!jbd_trylock_bh_state(bh)) { | |
330 | jbd_sync_bh(journal, bh); | |
331 | spin_lock(&journal->j_list_lock); | |
332 | retry = 1; | |
333 | break; | |
334 | } | |
335 | retry = __flush_buffer(journal, jh, bhs, &batch_count, &drop_count); | |
336 | if (cond_resched_lock(&journal->j_list_lock)) { | |
337 | retry = 1; | |
338 | break; | |
339 | } | |
340 | } while (jh != last_jh && !retry); | |
341 | ||
342 | if (batch_count) | |
343 | __flush_batch(journal, bhs, &batch_count); | |
344 | ||
345 | /* | |
346 | * If someone cleaned up this transaction while we slept, we're | |
347 | * done | |
348 | */ | |
349 | if (journal->j_checkpoint_transactions != transaction) | |
350 | break; | |
351 | if (retry) | |
352 | continue; | |
353 | /* | |
354 | * Maybe it's a new transaction, but it fell at the same | |
355 | * address | |
356 | */ | |
357 | if (transaction->t_tid != this_tid) | |
358 | continue; | |
359 | /* | |
360 | * We have walked the whole transaction list without | |
361 | * finding anything to write to disk. We had better be | |
362 | * able to make some progress or we are in trouble. | |
363 | */ | |
364 | cleanup_ret = __cleanup_transaction(journal, transaction); | |
365 | J_ASSERT(drop_count != 0 || cleanup_ret != 0); | |
366 | if (journal->j_checkpoint_transactions != transaction) | |
367 | break; | |
368 | } | |
369 | spin_unlock(&journal->j_list_lock); | |
370 | result = cleanup_journal_tail(journal); | |
371 | if (result < 0) | |
372 | return result; | |
373 | ||
374 | return 0; | |
375 | } | |
376 | ||
377 | /* | |
378 | * Check the list of checkpoint transactions for the journal to see if | |
379 | * we have already got rid of any since the last update of the log tail | |
380 | * in the journal superblock. If so, we can instantly roll the | |
381 | * superblock forward to remove those transactions from the log. | |
382 | * | |
383 | * Return <0 on error, 0 on success, 1 if there was nothing to clean up. | |
384 | * | |
385 | * Called with the journal lock held. | |
386 | * | |
387 | * This is the only part of the journaling code which really needs to be | |
388 | * aware of transaction aborts. Checkpointing involves writing to the | |
389 | * main filesystem area rather than to the journal, so it can proceed | |
390 | * even in abort state, but we must not update the journal superblock if | |
391 | * we have an abort error outstanding. | |
392 | */ | |
393 | ||
394 | int cleanup_journal_tail(journal_t *journal) | |
395 | { | |
396 | transaction_t * transaction; | |
397 | tid_t first_tid; | |
398 | unsigned long blocknr, freed; | |
399 | ||
400 | /* OK, work out the oldest transaction remaining in the log, and | |
401 | * the log block it starts at. | |
402 | * | |
403 | * If the log is now empty, we need to work out which is the | |
404 | * next transaction ID we will write, and where it will | |
405 | * start. */ | |
406 | ||
407 | spin_lock(&journal->j_state_lock); | |
408 | spin_lock(&journal->j_list_lock); | |
409 | transaction = journal->j_checkpoint_transactions; | |
410 | if (transaction) { | |
411 | first_tid = transaction->t_tid; | |
412 | blocknr = transaction->t_log_start; | |
413 | } else if ((transaction = journal->j_committing_transaction) != NULL) { | |
414 | first_tid = transaction->t_tid; | |
415 | blocknr = transaction->t_log_start; | |
416 | } else if ((transaction = journal->j_running_transaction) != NULL) { | |
417 | first_tid = transaction->t_tid; | |
418 | blocknr = journal->j_head; | |
419 | } else { | |
420 | first_tid = journal->j_transaction_sequence; | |
421 | blocknr = journal->j_head; | |
422 | } | |
423 | spin_unlock(&journal->j_list_lock); | |
424 | J_ASSERT(blocknr != 0); | |
425 | ||
426 | /* If the oldest pinned transaction is at the tail of the log | |
427 | already then there's not much we can do right now. */ | |
428 | if (journal->j_tail_sequence == first_tid) { | |
429 | spin_unlock(&journal->j_state_lock); | |
430 | return 1; | |
431 | } | |
432 | ||
433 | /* OK, update the superblock to recover the freed space. | |
434 | * Physical blocks come first: have we wrapped beyond the end of | |
435 | * the log? */ | |
436 | freed = blocknr - journal->j_tail; | |
437 | if (blocknr < journal->j_tail) | |
438 | freed = freed + journal->j_last - journal->j_first; | |
439 | ||
440 | jbd_debug(1, | |
441 | "Cleaning journal tail from %d to %d (offset %lu), " | |
442 | "freeing %lu\n", | |
443 | journal->j_tail_sequence, first_tid, blocknr, freed); | |
444 | ||
445 | journal->j_free += freed; | |
446 | journal->j_tail_sequence = first_tid; | |
447 | journal->j_tail = blocknr; | |
448 | spin_unlock(&journal->j_state_lock); | |
449 | if (!(journal->j_flags & JFS_ABORT)) | |
450 | journal_update_superblock(journal, 1); | |
451 | return 0; | |
452 | } | |
453 | ||
454 | ||
455 | /* Checkpoint list management */ | |
456 | ||
457 | /* | |
458 | * journal_clean_checkpoint_list | |
459 | * | |
460 | * Find all the written-back checkpoint buffers in the journal and release them. | |
461 | * | |
462 | * Called with the journal locked. | |
463 | * Called with j_list_lock held. | |
464 | * Returns number of bufers reaped (for debug) | |
465 | */ | |
466 | ||
467 | int __journal_clean_checkpoint_list(journal_t *journal) | |
468 | { | |
469 | transaction_t *transaction, *last_transaction, *next_transaction; | |
470 | int ret = 0; | |
471 | ||
472 | transaction = journal->j_checkpoint_transactions; | |
473 | if (transaction == 0) | |
474 | goto out; | |
475 | ||
476 | last_transaction = transaction->t_cpprev; | |
477 | next_transaction = transaction; | |
478 | do { | |
479 | struct journal_head *jh; | |
480 | ||
481 | transaction = next_transaction; | |
482 | next_transaction = transaction->t_cpnext; | |
483 | jh = transaction->t_checkpoint_list; | |
484 | if (jh) { | |
485 | struct journal_head *last_jh = jh->b_cpprev; | |
486 | struct journal_head *next_jh = jh; | |
487 | ||
488 | do { | |
489 | jh = next_jh; | |
490 | next_jh = jh->b_cpnext; | |
491 | /* Use trylock because of the ranknig */ | |
492 | if (jbd_trylock_bh_state(jh2bh(jh))) | |
493 | ret += __try_to_free_cp_buf(jh); | |
494 | /* | |
495 | * This function only frees up some memory | |
496 | * if possible so we dont have an obligation | |
497 | * to finish processing. Bail out if preemption | |
498 | * requested: | |
499 | */ | |
500 | if (need_resched()) | |
501 | goto out; | |
502 | } while (jh != last_jh); | |
503 | } | |
504 | } while (transaction != last_transaction); | |
505 | out: | |
506 | return ret; | |
507 | } | |
508 | ||
509 | /* | |
510 | * journal_remove_checkpoint: called after a buffer has been committed | |
511 | * to disk (either by being write-back flushed to disk, or being | |
512 | * committed to the log). | |
513 | * | |
514 | * We cannot safely clean a transaction out of the log until all of the | |
515 | * buffer updates committed in that transaction have safely been stored | |
516 | * elsewhere on disk. To achieve this, all of the buffers in a | |
517 | * transaction need to be maintained on the transaction's checkpoint | |
518 | * list until they have been rewritten, at which point this function is | |
519 | * called to remove the buffer from the existing transaction's | |
520 | * checkpoint list. | |
521 | * | |
522 | * This function is called with the journal locked. | |
523 | * This function is called with j_list_lock held. | |
524 | */ | |
525 | ||
526 | void __journal_remove_checkpoint(struct journal_head *jh) | |
527 | { | |
528 | transaction_t *transaction; | |
529 | journal_t *journal; | |
530 | ||
531 | JBUFFER_TRACE(jh, "entry"); | |
532 | ||
533 | if ((transaction = jh->b_cp_transaction) == NULL) { | |
534 | JBUFFER_TRACE(jh, "not on transaction"); | |
535 | goto out; | |
536 | } | |
537 | journal = transaction->t_journal; | |
538 | ||
539 | __buffer_unlink(jh); | |
540 | ||
541 | if (transaction->t_checkpoint_list != NULL) | |
542 | goto out; | |
543 | JBUFFER_TRACE(jh, "transaction has no more buffers"); | |
544 | ||
545 | /* | |
546 | * There is one special case to worry about: if we have just pulled the | |
547 | * buffer off a committing transaction's forget list, then even if the | |
548 | * checkpoint list is empty, the transaction obviously cannot be | |
549 | * dropped! | |
550 | * | |
551 | * The locking here around j_committing_transaction is a bit sleazy. | |
552 | * See the comment at the end of journal_commit_transaction(). | |
553 | */ | |
554 | if (transaction == journal->j_committing_transaction) { | |
555 | JBUFFER_TRACE(jh, "belongs to committing transaction"); | |
556 | goto out; | |
557 | } | |
558 | ||
559 | /* OK, that was the last buffer for the transaction: we can now | |
560 | safely remove this transaction from the log */ | |
561 | ||
562 | __journal_drop_transaction(journal, transaction); | |
563 | ||
564 | /* Just in case anybody was waiting for more transactions to be | |
565 | checkpointed... */ | |
566 | wake_up(&journal->j_wait_logspace); | |
567 | out: | |
568 | JBUFFER_TRACE(jh, "exit"); | |
569 | } | |
570 | ||
571 | /* | |
572 | * journal_insert_checkpoint: put a committed buffer onto a checkpoint | |
573 | * list so that we know when it is safe to clean the transaction out of | |
574 | * the log. | |
575 | * | |
576 | * Called with the journal locked. | |
577 | * Called with j_list_lock held. | |
578 | */ | |
579 | void __journal_insert_checkpoint(struct journal_head *jh, | |
580 | transaction_t *transaction) | |
581 | { | |
582 | JBUFFER_TRACE(jh, "entry"); | |
583 | J_ASSERT_JH(jh, buffer_dirty(jh2bh(jh)) || buffer_jbddirty(jh2bh(jh))); | |
584 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); | |
585 | ||
586 | jh->b_cp_transaction = transaction; | |
587 | ||
588 | if (!transaction->t_checkpoint_list) { | |
589 | jh->b_cpnext = jh->b_cpprev = jh; | |
590 | } else { | |
591 | jh->b_cpnext = transaction->t_checkpoint_list; | |
592 | jh->b_cpprev = transaction->t_checkpoint_list->b_cpprev; | |
593 | jh->b_cpprev->b_cpnext = jh; | |
594 | jh->b_cpnext->b_cpprev = jh; | |
595 | } | |
596 | transaction->t_checkpoint_list = jh; | |
597 | } | |
598 | ||
599 | /* | |
600 | * We've finished with this transaction structure: adios... | |
601 | * | |
602 | * The transaction must have no links except for the checkpoint by this | |
603 | * point. | |
604 | * | |
605 | * Called with the journal locked. | |
606 | * Called with j_list_lock held. | |
607 | */ | |
608 | ||
609 | void __journal_drop_transaction(journal_t *journal, transaction_t *transaction) | |
610 | { | |
611 | assert_spin_locked(&journal->j_list_lock); | |
612 | if (transaction->t_cpnext) { | |
613 | transaction->t_cpnext->t_cpprev = transaction->t_cpprev; | |
614 | transaction->t_cpprev->t_cpnext = transaction->t_cpnext; | |
615 | if (journal->j_checkpoint_transactions == transaction) | |
616 | journal->j_checkpoint_transactions = | |
617 | transaction->t_cpnext; | |
618 | if (journal->j_checkpoint_transactions == transaction) | |
619 | journal->j_checkpoint_transactions = NULL; | |
620 | } | |
621 | ||
622 | J_ASSERT(transaction->t_state == T_FINISHED); | |
623 | J_ASSERT(transaction->t_buffers == NULL); | |
624 | J_ASSERT(transaction->t_sync_datalist == NULL); | |
625 | J_ASSERT(transaction->t_forget == NULL); | |
626 | J_ASSERT(transaction->t_iobuf_list == NULL); | |
627 | J_ASSERT(transaction->t_shadow_list == NULL); | |
628 | J_ASSERT(transaction->t_log_list == NULL); | |
629 | J_ASSERT(transaction->t_checkpoint_list == NULL); | |
630 | J_ASSERT(transaction->t_updates == 0); | |
631 | J_ASSERT(journal->j_committing_transaction != transaction); | |
632 | J_ASSERT(journal->j_running_transaction != transaction); | |
633 | ||
634 | jbd_debug(1, "Dropping transaction %d, all done\n", transaction->t_tid); | |
635 | kfree(transaction); | |
636 | } |