Commit | Line | Data |
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1da177e4 | 1 | /* |
f30c2269 | 2 | * linux/fs/jbd/journal.c |
1da177e4 LT |
3 | * |
4 | * Written by Stephen C. Tweedie <sct@redhat.com>, 1998 | |
5 | * | |
6 | * Copyright 1998 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 | * Generic filesystem journal-writing code; part of the ext2fs | |
13 | * journaling system. | |
14 | * | |
15 | * This file manages journals: areas of disk reserved for logging | |
16 | * transactional updates. This includes the kernel journaling thread | |
17 | * which is responsible for scheduling updates to the log. | |
18 | * | |
19 | * We do not actually manage the physical storage of the journal in this | |
20 | * file: that is left to a per-journal policy function, which allows us | |
21 | * to store the journal within a filesystem-specified area for ext2 | |
22 | * journaling (ext2 can use a reserved inode for storing the log). | |
23 | */ | |
24 | ||
25 | #include <linux/module.h> | |
26 | #include <linux/time.h> | |
27 | #include <linux/fs.h> | |
28 | #include <linux/jbd.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/slab.h> | |
1da177e4 LT |
31 | #include <linux/init.h> |
32 | #include <linux/mm.h> | |
7dfb7103 | 33 | #include <linux/freezer.h> |
1da177e4 | 34 | #include <linux/pagemap.h> |
8d8c8511 | 35 | #include <linux/kthread.h> |
c9cf5528 | 36 | #include <linux/poison.h> |
8d8c8511 | 37 | #include <linux/proc_fs.h> |
c2a9159c | 38 | #include <linux/debugfs.h> |
f81e3d45 | 39 | #include <linux/ratelimit.h> |
8d8c8511 | 40 | |
99cb1a31 LC |
41 | #define CREATE_TRACE_POINTS |
42 | #include <trace/events/jbd.h> | |
43 | ||
1da177e4 LT |
44 | #include <asm/uaccess.h> |
45 | #include <asm/page.h> | |
1da177e4 LT |
46 | |
47 | EXPORT_SYMBOL(journal_start); | |
48 | EXPORT_SYMBOL(journal_restart); | |
49 | EXPORT_SYMBOL(journal_extend); | |
50 | EXPORT_SYMBOL(journal_stop); | |
51 | EXPORT_SYMBOL(journal_lock_updates); | |
52 | EXPORT_SYMBOL(journal_unlock_updates); | |
53 | EXPORT_SYMBOL(journal_get_write_access); | |
54 | EXPORT_SYMBOL(journal_get_create_access); | |
55 | EXPORT_SYMBOL(journal_get_undo_access); | |
56 | EXPORT_SYMBOL(journal_dirty_data); | |
57 | EXPORT_SYMBOL(journal_dirty_metadata); | |
58 | EXPORT_SYMBOL(journal_release_buffer); | |
59 | EXPORT_SYMBOL(journal_forget); | |
60 | #if 0 | |
61 | EXPORT_SYMBOL(journal_sync_buffer); | |
62 | #endif | |
63 | EXPORT_SYMBOL(journal_flush); | |
64 | EXPORT_SYMBOL(journal_revoke); | |
65 | ||
66 | EXPORT_SYMBOL(journal_init_dev); | |
67 | EXPORT_SYMBOL(journal_init_inode); | |
68 | EXPORT_SYMBOL(journal_update_format); | |
69 | EXPORT_SYMBOL(journal_check_used_features); | |
70 | EXPORT_SYMBOL(journal_check_available_features); | |
71 | EXPORT_SYMBOL(journal_set_features); | |
72 | EXPORT_SYMBOL(journal_create); | |
73 | EXPORT_SYMBOL(journal_load); | |
74 | EXPORT_SYMBOL(journal_destroy); | |
1da177e4 LT |
75 | EXPORT_SYMBOL(journal_abort); |
76 | EXPORT_SYMBOL(journal_errno); | |
77 | EXPORT_SYMBOL(journal_ack_err); | |
78 | EXPORT_SYMBOL(journal_clear_err); | |
79 | EXPORT_SYMBOL(log_wait_commit); | |
ff5e4b51 | 80 | EXPORT_SYMBOL(log_start_commit); |
1da177e4 LT |
81 | EXPORT_SYMBOL(journal_start_commit); |
82 | EXPORT_SYMBOL(journal_force_commit_nested); | |
83 | EXPORT_SYMBOL(journal_wipe); | |
84 | EXPORT_SYMBOL(journal_blocks_per_page); | |
85 | EXPORT_SYMBOL(journal_invalidatepage); | |
86 | EXPORT_SYMBOL(journal_try_to_free_buffers); | |
87 | EXPORT_SYMBOL(journal_force_commit); | |
88 | ||
89 | static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *); | |
022a4a7b | 90 | static void __journal_abort_soft (journal_t *journal, int errno); |
dff6825e | 91 | static const char *journal_dev_name(journal_t *journal, char *buffer); |
1da177e4 | 92 | |
e99a03c6 PG |
93 | #ifdef CONFIG_JBD_DEBUG |
94 | void __jbd_debug(int level, const char *file, const char *func, | |
95 | unsigned int line, const char *fmt, ...) | |
96 | { | |
97 | struct va_format vaf; | |
98 | va_list args; | |
99 | ||
100 | if (level > journal_enable_debug) | |
101 | return; | |
102 | va_start(args, fmt); | |
103 | vaf.fmt = fmt; | |
104 | vaf.va = &args; | |
105 | printk(KERN_DEBUG "%s: (%s, %u): %pV\n", file, func, line, &vaf); | |
106 | va_end(args); | |
107 | } | |
108 | EXPORT_SYMBOL(__jbd_debug); | |
109 | #endif | |
110 | ||
1da177e4 LT |
111 | /* |
112 | * Helper function used to manage commit timeouts | |
113 | */ | |
114 | ||
115 | static void commit_timeout(unsigned long __data) | |
116 | { | |
117 | struct task_struct * p = (struct task_struct *) __data; | |
118 | ||
119 | wake_up_process(p); | |
120 | } | |
121 | ||
1da177e4 LT |
122 | /* |
123 | * kjournald: The main thread function used to manage a logging device | |
124 | * journal. | |
125 | * | |
126 | * This kernel thread is responsible for two things: | |
127 | * | |
128 | * 1) COMMIT: Every so often we need to commit the current state of the | |
129 | * filesystem to disk. The journal thread is responsible for writing | |
130 | * all of the metadata buffers to disk. | |
131 | * | |
132 | * 2) CHECKPOINT: We cannot reuse a used section of the log file until all | |
133 | * of the data in that part of the log has been rewritten elsewhere on | |
134 | * the disk. Flushing these old buffers to reclaim space in the log is | |
135 | * known as checkpointing, and this thread is responsible for that job. | |
136 | */ | |
137 | ||
022a4a7b | 138 | static int kjournald(void *arg) |
1da177e4 | 139 | { |
e3df1898 | 140 | journal_t *journal = arg; |
1da177e4 | 141 | transaction_t *transaction; |
1da177e4 | 142 | |
e3df1898 AM |
143 | /* |
144 | * Set up an interval timer which can be used to trigger a commit wakeup | |
145 | * after the commit interval expires | |
146 | */ | |
147 | setup_timer(&journal->j_commit_timer, commit_timeout, | |
148 | (unsigned long)current); | |
1da177e4 | 149 | |
35c80422 NC |
150 | set_freezable(); |
151 | ||
1da177e4 LT |
152 | /* Record that the journal thread is running */ |
153 | journal->j_task = current; | |
154 | wake_up(&journal->j_wait_done_commit); | |
155 | ||
156 | printk(KERN_INFO "kjournald starting. Commit interval %ld seconds\n", | |
157 | journal->j_commit_interval / HZ); | |
158 | ||
159 | /* | |
160 | * And now, wait forever for commit wakeup events. | |
161 | */ | |
162 | spin_lock(&journal->j_state_lock); | |
163 | ||
164 | loop: | |
165 | if (journal->j_flags & JFS_UNMOUNT) | |
166 | goto end_loop; | |
167 | ||
168 | jbd_debug(1, "commit_sequence=%d, commit_request=%d\n", | |
169 | journal->j_commit_sequence, journal->j_commit_request); | |
170 | ||
171 | if (journal->j_commit_sequence != journal->j_commit_request) { | |
172 | jbd_debug(1, "OK, requests differ\n"); | |
173 | spin_unlock(&journal->j_state_lock); | |
e3df1898 | 174 | del_timer_sync(&journal->j_commit_timer); |
1da177e4 LT |
175 | journal_commit_transaction(journal); |
176 | spin_lock(&journal->j_state_lock); | |
177 | goto loop; | |
178 | } | |
179 | ||
180 | wake_up(&journal->j_wait_done_commit); | |
3e1d1d28 | 181 | if (freezing(current)) { |
1da177e4 LT |
182 | /* |
183 | * The simpler the better. Flushing journal isn't a | |
184 | * good idea, because that depends on threads that may | |
185 | * be already stopped. | |
186 | */ | |
187 | jbd_debug(1, "Now suspending kjournald\n"); | |
188 | spin_unlock(&journal->j_state_lock); | |
a0acae0e | 189 | try_to_freeze(); |
1da177e4 LT |
190 | spin_lock(&journal->j_state_lock); |
191 | } else { | |
192 | /* | |
193 | * We assume on resume that commits are already there, | |
194 | * so we don't sleep | |
195 | */ | |
196 | DEFINE_WAIT(wait); | |
197 | int should_sleep = 1; | |
198 | ||
199 | prepare_to_wait(&journal->j_wait_commit, &wait, | |
200 | TASK_INTERRUPTIBLE); | |
201 | if (journal->j_commit_sequence != journal->j_commit_request) | |
202 | should_sleep = 0; | |
203 | transaction = journal->j_running_transaction; | |
204 | if (transaction && time_after_eq(jiffies, | |
205 | transaction->t_expires)) | |
206 | should_sleep = 0; | |
cbf0d27a | 207 | if (journal->j_flags & JFS_UNMOUNT) |
e9ad5620 | 208 | should_sleep = 0; |
1da177e4 LT |
209 | if (should_sleep) { |
210 | spin_unlock(&journal->j_state_lock); | |
211 | schedule(); | |
212 | spin_lock(&journal->j_state_lock); | |
213 | } | |
214 | finish_wait(&journal->j_wait_commit, &wait); | |
215 | } | |
216 | ||
217 | jbd_debug(1, "kjournald wakes\n"); | |
218 | ||
219 | /* | |
220 | * Were we woken up by a commit wakeup event? | |
221 | */ | |
222 | transaction = journal->j_running_transaction; | |
223 | if (transaction && time_after_eq(jiffies, transaction->t_expires)) { | |
224 | journal->j_commit_request = transaction->t_tid; | |
225 | jbd_debug(1, "woke because of timeout\n"); | |
226 | } | |
227 | goto loop; | |
228 | ||
229 | end_loop: | |
230 | spin_unlock(&journal->j_state_lock); | |
e3df1898 | 231 | del_timer_sync(&journal->j_commit_timer); |
1da177e4 LT |
232 | journal->j_task = NULL; |
233 | wake_up(&journal->j_wait_done_commit); | |
234 | jbd_debug(1, "Journal thread exiting.\n"); | |
235 | return 0; | |
236 | } | |
237 | ||
97f06784 | 238 | static int journal_start_thread(journal_t *journal) |
1da177e4 | 239 | { |
97f06784 PE |
240 | struct task_struct *t; |
241 | ||
242 | t = kthread_run(kjournald, journal, "kjournald"); | |
243 | if (IS_ERR(t)) | |
244 | return PTR_ERR(t); | |
245 | ||
c80544dc | 246 | wait_event(journal->j_wait_done_commit, journal->j_task != NULL); |
97f06784 | 247 | return 0; |
1da177e4 LT |
248 | } |
249 | ||
250 | static void journal_kill_thread(journal_t *journal) | |
251 | { | |
252 | spin_lock(&journal->j_state_lock); | |
253 | journal->j_flags |= JFS_UNMOUNT; | |
254 | ||
255 | while (journal->j_task) { | |
256 | wake_up(&journal->j_wait_commit); | |
257 | spin_unlock(&journal->j_state_lock); | |
c80544dc SH |
258 | wait_event(journal->j_wait_done_commit, |
259 | journal->j_task == NULL); | |
1da177e4 LT |
260 | spin_lock(&journal->j_state_lock); |
261 | } | |
262 | spin_unlock(&journal->j_state_lock); | |
263 | } | |
264 | ||
265 | /* | |
266 | * journal_write_metadata_buffer: write a metadata buffer to the journal. | |
267 | * | |
268 | * Writes a metadata buffer to a given disk block. The actual IO is not | |
269 | * performed but a new buffer_head is constructed which labels the data | |
270 | * to be written with the correct destination disk block. | |
271 | * | |
272 | * Any magic-number escaping which needs to be done will cause a | |
273 | * copy-out here. If the buffer happens to start with the | |
274 | * JFS_MAGIC_NUMBER, then we can't write it to the log directly: the | |
275 | * magic number is only written to the log for descripter blocks. In | |
276 | * this case, we copy the data and replace the first word with 0, and we | |
277 | * return a result code which indicates that this buffer needs to be | |
278 | * marked as an escaped buffer in the corresponding log descriptor | |
279 | * block. The missing word can then be restored when the block is read | |
280 | * during recovery. | |
281 | * | |
282 | * If the source buffer has already been modified by a new transaction | |
283 | * since we took the last commit snapshot, we use the frozen copy of | |
284 | * that data for IO. If we end up using the existing buffer_head's data | |
285 | * for the write, then we *have* to lock the buffer to prevent anyone | |
286 | * else from using and possibly modifying it while the IO is in | |
287 | * progress. | |
288 | * | |
289 | * The function returns a pointer to the buffer_heads to be used for IO. | |
290 | * | |
291 | * We assume that the journal has already been locked in this function. | |
292 | * | |
293 | * Return value: | |
294 | * <0: Error | |
295 | * >=0: Finished OK | |
296 | * | |
297 | * On success: | |
298 | * Bit 0 set == escape performed on the data | |
299 | * Bit 1 set == buffer copy-out performed (kfree the data after IO) | |
300 | */ | |
301 | ||
302 | int journal_write_metadata_buffer(transaction_t *transaction, | |
303 | struct journal_head *jh_in, | |
304 | struct journal_head **jh_out, | |
9c28cbcc | 305 | unsigned int blocknr) |
1da177e4 LT |
306 | { |
307 | int need_copy_out = 0; | |
308 | int done_copy_out = 0; | |
309 | int do_escape = 0; | |
310 | char *mapped_data; | |
311 | struct buffer_head *new_bh; | |
312 | struct journal_head *new_jh; | |
313 | struct page *new_page; | |
314 | unsigned int new_offset; | |
315 | struct buffer_head *bh_in = jh2bh(jh_in); | |
f1015c44 | 316 | journal_t *journal = transaction->t_journal; |
1da177e4 LT |
317 | |
318 | /* | |
319 | * The buffer really shouldn't be locked: only the current committing | |
320 | * transaction is allowed to write it, so nobody else is allowed | |
321 | * to do any IO. | |
322 | * | |
323 | * akpm: except if we're journalling data, and write() output is | |
324 | * also part of a shared mapping, and another thread has | |
325 | * decided to launch a writepage() against this buffer. | |
326 | */ | |
327 | J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in)); | |
328 | ||
329 | new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL); | |
f1015c44 | 330 | /* keep subsequent assertions sane */ |
f1015c44 | 331 | atomic_set(&new_bh->b_count, 1); |
332 | new_jh = journal_add_journal_head(new_bh); /* This sleeps */ | |
1da177e4 LT |
333 | |
334 | /* | |
335 | * If a new transaction has already done a buffer copy-out, then | |
336 | * we use that version of the data for the commit. | |
337 | */ | |
338 | jbd_lock_bh_state(bh_in); | |
339 | repeat: | |
340 | if (jh_in->b_frozen_data) { | |
341 | done_copy_out = 1; | |
342 | new_page = virt_to_page(jh_in->b_frozen_data); | |
343 | new_offset = offset_in_page(jh_in->b_frozen_data); | |
344 | } else { | |
345 | new_page = jh2bh(jh_in)->b_page; | |
346 | new_offset = offset_in_page(jh2bh(jh_in)->b_data); | |
347 | } | |
348 | ||
8fb53c46 | 349 | mapped_data = kmap_atomic(new_page); |
1da177e4 LT |
350 | /* |
351 | * Check for escaping | |
352 | */ | |
353 | if (*((__be32 *)(mapped_data + new_offset)) == | |
354 | cpu_to_be32(JFS_MAGIC_NUMBER)) { | |
355 | need_copy_out = 1; | |
356 | do_escape = 1; | |
357 | } | |
8fb53c46 | 358 | kunmap_atomic(mapped_data); |
1da177e4 LT |
359 | |
360 | /* | |
361 | * Do we need to do a data copy? | |
362 | */ | |
363 | if (need_copy_out && !done_copy_out) { | |
364 | char *tmp; | |
365 | ||
366 | jbd_unlock_bh_state(bh_in); | |
c089d490 | 367 | tmp = jbd_alloc(bh_in->b_size, GFP_NOFS); |
1da177e4 LT |
368 | jbd_lock_bh_state(bh_in); |
369 | if (jh_in->b_frozen_data) { | |
c089d490 | 370 | jbd_free(tmp, bh_in->b_size); |
1da177e4 LT |
371 | goto repeat; |
372 | } | |
373 | ||
374 | jh_in->b_frozen_data = tmp; | |
8fb53c46 | 375 | mapped_data = kmap_atomic(new_page); |
1da177e4 | 376 | memcpy(tmp, mapped_data + new_offset, jh2bh(jh_in)->b_size); |
8fb53c46 | 377 | kunmap_atomic(mapped_data); |
1da177e4 LT |
378 | |
379 | new_page = virt_to_page(tmp); | |
380 | new_offset = offset_in_page(tmp); | |
381 | done_copy_out = 1; | |
382 | } | |
383 | ||
384 | /* | |
385 | * Did we need to do an escaping? Now we've done all the | |
386 | * copying, we can finally do so. | |
387 | */ | |
388 | if (do_escape) { | |
8fb53c46 | 389 | mapped_data = kmap_atomic(new_page); |
1da177e4 | 390 | *((unsigned int *)(mapped_data + new_offset)) = 0; |
8fb53c46 | 391 | kunmap_atomic(mapped_data); |
1da177e4 LT |
392 | } |
393 | ||
1da177e4 LT |
394 | set_bh_page(new_bh, new_page, new_offset); |
395 | new_jh->b_transaction = NULL; | |
396 | new_bh->b_size = jh2bh(jh_in)->b_size; | |
397 | new_bh->b_bdev = transaction->t_journal->j_dev; | |
398 | new_bh->b_blocknr = blocknr; | |
399 | set_buffer_mapped(new_bh); | |
400 | set_buffer_dirty(new_bh); | |
401 | ||
402 | *jh_out = new_jh; | |
403 | ||
404 | /* | |
405 | * The to-be-written buffer needs to get moved to the io queue, | |
406 | * and the original buffer whose contents we are shadowing or | |
407 | * copying is moved to the transaction's shadow queue. | |
408 | */ | |
409 | JBUFFER_TRACE(jh_in, "file as BJ_Shadow"); | |
f1015c44 | 410 | spin_lock(&journal->j_list_lock); |
411 | __journal_file_buffer(jh_in, transaction, BJ_Shadow); | |
412 | spin_unlock(&journal->j_list_lock); | |
413 | jbd_unlock_bh_state(bh_in); | |
414 | ||
1da177e4 LT |
415 | JBUFFER_TRACE(new_jh, "file as BJ_IO"); |
416 | journal_file_buffer(new_jh, transaction, BJ_IO); | |
417 | ||
418 | return do_escape | (done_copy_out << 1); | |
419 | } | |
420 | ||
421 | /* | |
422 | * Allocation code for the journal file. Manage the space left in the | |
423 | * journal, so that we can begin checkpointing when appropriate. | |
424 | */ | |
425 | ||
426 | /* | |
427 | * __log_space_left: Return the number of free blocks left in the journal. | |
428 | * | |
429 | * Called with the journal already locked. | |
430 | * | |
431 | * Called under j_state_lock | |
432 | */ | |
433 | ||
434 | int __log_space_left(journal_t *journal) | |
435 | { | |
436 | int left = journal->j_free; | |
437 | ||
438 | assert_spin_locked(&journal->j_state_lock); | |
439 | ||
440 | /* | |
441 | * Be pessimistic here about the number of those free blocks which | |
442 | * might be required for log descriptor control blocks. | |
443 | */ | |
444 | ||
445 | #define MIN_LOG_RESERVED_BLOCKS 32 /* Allow for rounding errors */ | |
446 | ||
447 | left -= MIN_LOG_RESERVED_BLOCKS; | |
448 | ||
449 | if (left <= 0) | |
450 | return 0; | |
451 | left -= (left >> 3); | |
452 | return left; | |
453 | } | |
454 | ||
455 | /* | |
8fe4cd0d | 456 | * Called under j_state_lock. Returns true if a transaction commit was started. |
1da177e4 LT |
457 | */ |
458 | int __log_start_commit(journal_t *journal, tid_t target) | |
459 | { | |
460 | /* | |
d9b01934 TT |
461 | * The only transaction we can possibly wait upon is the |
462 | * currently running transaction (if it exists). Otherwise, | |
463 | * the target tid must be an old one. | |
1da177e4 | 464 | */ |
7e2fb2d7 ES |
465 | if (journal->j_commit_request != target && |
466 | journal->j_running_transaction && | |
d9b01934 | 467 | journal->j_running_transaction->t_tid == target) { |
1da177e4 | 468 | /* |
bcf3d0bc | 469 | * We want a new commit: OK, mark the request and wakeup the |
1da177e4 LT |
470 | * commit thread. We do _not_ do the commit ourselves. |
471 | */ | |
472 | ||
473 | journal->j_commit_request = target; | |
474 | jbd_debug(1, "JBD: requesting commit %d/%d\n", | |
475 | journal->j_commit_request, | |
476 | journal->j_commit_sequence); | |
477 | wake_up(&journal->j_wait_commit); | |
478 | return 1; | |
d9b01934 TT |
479 | } else if (!tid_geq(journal->j_commit_request, target)) |
480 | /* This should never happen, but if it does, preserve | |
481 | the evidence before kjournald goes into a loop and | |
482 | increments j_commit_sequence beyond all recognition. */ | |
483 | WARN_ONCE(1, "jbd: bad log_start_commit: %u %u %u %u\n", | |
484 | journal->j_commit_request, journal->j_commit_sequence, | |
485 | target, journal->j_running_transaction ? | |
486 | journal->j_running_transaction->t_tid : 0); | |
1da177e4 LT |
487 | return 0; |
488 | } | |
489 | ||
490 | int log_start_commit(journal_t *journal, tid_t tid) | |
491 | { | |
492 | int ret; | |
493 | ||
494 | spin_lock(&journal->j_state_lock); | |
495 | ret = __log_start_commit(journal, tid); | |
496 | spin_unlock(&journal->j_state_lock); | |
497 | return ret; | |
498 | } | |
499 | ||
500 | /* | |
501 | * Force and wait upon a commit if the calling process is not within | |
502 | * transaction. This is used for forcing out undo-protected data which contains | |
503 | * bitmaps, when the fs is running out of space. | |
504 | * | |
505 | * We can only force the running transaction if we don't have an active handle; | |
506 | * otherwise, we will deadlock. | |
507 | * | |
508 | * Returns true if a transaction was started. | |
509 | */ | |
510 | int journal_force_commit_nested(journal_t *journal) | |
511 | { | |
512 | transaction_t *transaction = NULL; | |
513 | tid_t tid; | |
514 | ||
515 | spin_lock(&journal->j_state_lock); | |
516 | if (journal->j_running_transaction && !current->journal_info) { | |
517 | transaction = journal->j_running_transaction; | |
518 | __log_start_commit(journal, transaction->t_tid); | |
519 | } else if (journal->j_committing_transaction) | |
520 | transaction = journal->j_committing_transaction; | |
521 | ||
522 | if (!transaction) { | |
523 | spin_unlock(&journal->j_state_lock); | |
524 | return 0; /* Nothing to retry */ | |
525 | } | |
526 | ||
527 | tid = transaction->t_tid; | |
528 | spin_unlock(&journal->j_state_lock); | |
529 | log_wait_commit(journal, tid); | |
530 | return 1; | |
531 | } | |
532 | ||
533 | /* | |
534 | * Start a commit of the current running transaction (if any). Returns true | |
8fe4cd0d JK |
535 | * if a transaction is going to be committed (or is currently already |
536 | * committing), and fills its tid in at *ptid | |
1da177e4 LT |
537 | */ |
538 | int journal_start_commit(journal_t *journal, tid_t *ptid) | |
539 | { | |
540 | int ret = 0; | |
541 | ||
542 | spin_lock(&journal->j_state_lock); | |
543 | if (journal->j_running_transaction) { | |
544 | tid_t tid = journal->j_running_transaction->t_tid; | |
545 | ||
8fe4cd0d JK |
546 | __log_start_commit(journal, tid); |
547 | /* There's a running transaction and we've just made sure | |
548 | * it's commit has been scheduled. */ | |
549 | if (ptid) | |
1da177e4 | 550 | *ptid = tid; |
8fe4cd0d JK |
551 | ret = 1; |
552 | } else if (journal->j_committing_transaction) { | |
1da177e4 | 553 | /* |
12810ad7 AB |
554 | * If commit has been started, then we have to wait for |
555 | * completion of that transaction. | |
1da177e4 | 556 | */ |
8fe4cd0d JK |
557 | if (ptid) |
558 | *ptid = journal->j_committing_transaction->t_tid; | |
1da177e4 LT |
559 | ret = 1; |
560 | } | |
561 | spin_unlock(&journal->j_state_lock); | |
562 | return ret; | |
563 | } | |
564 | ||
565 | /* | |
566 | * Wait for a specified commit to complete. | |
567 | * The caller may not hold the journal lock. | |
568 | */ | |
569 | int log_wait_commit(journal_t *journal, tid_t tid) | |
570 | { | |
571 | int err = 0; | |
572 | ||
573 | #ifdef CONFIG_JBD_DEBUG | |
574 | spin_lock(&journal->j_state_lock); | |
575 | if (!tid_geq(journal->j_commit_request, tid)) { | |
576 | printk(KERN_EMERG | |
577 | "%s: error: j_commit_request=%d, tid=%d\n", | |
08fc99bf | 578 | __func__, journal->j_commit_request, tid); |
1da177e4 LT |
579 | } |
580 | spin_unlock(&journal->j_state_lock); | |
581 | #endif | |
582 | spin_lock(&journal->j_state_lock); | |
e678a4f0 JK |
583 | /* |
584 | * Not running or committing trans? Must be already committed. This | |
585 | * saves us from waiting for a *long* time when tid overflows. | |
586 | */ | |
587 | if (!((journal->j_running_transaction && | |
588 | journal->j_running_transaction->t_tid == tid) || | |
589 | (journal->j_committing_transaction && | |
590 | journal->j_committing_transaction->t_tid == tid))) | |
591 | goto out_unlock; | |
592 | ||
2db938be JK |
593 | if (!tid_geq(journal->j_commit_waited, tid)) |
594 | journal->j_commit_waited = tid; | |
1da177e4 LT |
595 | while (tid_gt(tid, journal->j_commit_sequence)) { |
596 | jbd_debug(1, "JBD: want %d, j_commit_sequence=%d\n", | |
597 | tid, journal->j_commit_sequence); | |
598 | wake_up(&journal->j_wait_commit); | |
599 | spin_unlock(&journal->j_state_lock); | |
600 | wait_event(journal->j_wait_done_commit, | |
601 | !tid_gt(tid, journal->j_commit_sequence)); | |
602 | spin_lock(&journal->j_state_lock); | |
603 | } | |
e678a4f0 | 604 | out_unlock: |
1da177e4 LT |
605 | spin_unlock(&journal->j_state_lock); |
606 | ||
607 | if (unlikely(is_journal_aborted(journal))) { | |
608 | printk(KERN_EMERG "journal commit I/O error\n"); | |
609 | err = -EIO; | |
610 | } | |
611 | return err; | |
612 | } | |
613 | ||
03f4d804 JK |
614 | /* |
615 | * Return 1 if a given transaction has not yet sent barrier request | |
616 | * connected with a transaction commit. If 0 is returned, transaction | |
617 | * may or may not have sent the barrier. Used to avoid sending barrier | |
618 | * twice in common cases. | |
619 | */ | |
620 | int journal_trans_will_send_data_barrier(journal_t *journal, tid_t tid) | |
621 | { | |
622 | int ret = 0; | |
623 | transaction_t *commit_trans; | |
624 | ||
625 | if (!(journal->j_flags & JFS_BARRIER)) | |
626 | return 0; | |
627 | spin_lock(&journal->j_state_lock); | |
628 | /* Transaction already committed? */ | |
629 | if (tid_geq(journal->j_commit_sequence, tid)) | |
630 | goto out; | |
631 | /* | |
632 | * Transaction is being committed and we already proceeded to | |
633 | * writing commit record? | |
634 | */ | |
635 | commit_trans = journal->j_committing_transaction; | |
636 | if (commit_trans && commit_trans->t_tid == tid && | |
637 | commit_trans->t_state >= T_COMMIT_RECORD) | |
638 | goto out; | |
639 | ret = 1; | |
640 | out: | |
641 | spin_unlock(&journal->j_state_lock); | |
642 | return ret; | |
643 | } | |
52779708 | 644 | EXPORT_SYMBOL(journal_trans_will_send_data_barrier); |
03f4d804 | 645 | |
1da177e4 LT |
646 | /* |
647 | * Log buffer allocation routines: | |
648 | */ | |
649 | ||
9c28cbcc | 650 | int journal_next_log_block(journal_t *journal, unsigned int *retp) |
1da177e4 | 651 | { |
9c28cbcc | 652 | unsigned int blocknr; |
1da177e4 LT |
653 | |
654 | spin_lock(&journal->j_state_lock); | |
655 | J_ASSERT(journal->j_free > 1); | |
656 | ||
657 | blocknr = journal->j_head; | |
658 | journal->j_head++; | |
659 | journal->j_free--; | |
660 | if (journal->j_head == journal->j_last) | |
661 | journal->j_head = journal->j_first; | |
662 | spin_unlock(&journal->j_state_lock); | |
663 | return journal_bmap(journal, blocknr, retp); | |
664 | } | |
665 | ||
666 | /* | |
667 | * Conversion of logical to physical block numbers for the journal | |
668 | * | |
669 | * On external journals the journal blocks are identity-mapped, so | |
670 | * this is a no-op. If needed, we can use j_blk_offset - everything is | |
671 | * ready. | |
672 | */ | |
9c28cbcc JK |
673 | int journal_bmap(journal_t *journal, unsigned int blocknr, |
674 | unsigned int *retp) | |
1da177e4 LT |
675 | { |
676 | int err = 0; | |
9c28cbcc | 677 | unsigned int ret; |
1da177e4 LT |
678 | |
679 | if (journal->j_inode) { | |
680 | ret = bmap(journal->j_inode, blocknr); | |
681 | if (ret) | |
682 | *retp = ret; | |
683 | else { | |
684 | char b[BDEVNAME_SIZE]; | |
685 | ||
686 | printk(KERN_ALERT "%s: journal block not found " | |
9c28cbcc | 687 | "at offset %u on %s\n", |
08fc99bf | 688 | __func__, |
1da177e4 LT |
689 | blocknr, |
690 | bdevname(journal->j_dev, b)); | |
691 | err = -EIO; | |
692 | __journal_abort_soft(journal, err); | |
693 | } | |
694 | } else { | |
695 | *retp = blocknr; /* +journal->j_blk_offset */ | |
696 | } | |
697 | return err; | |
698 | } | |
699 | ||
700 | /* | |
701 | * We play buffer_head aliasing tricks to write data/metadata blocks to | |
702 | * the journal without copying their contents, but for journal | |
703 | * descriptor blocks we do need to generate bona fide buffers. | |
704 | * | |
705 | * After the caller of journal_get_descriptor_buffer() has finished modifying | |
706 | * the buffer's contents they really should run flush_dcache_page(bh->b_page). | |
707 | * But we don't bother doing that, so there will be coherency problems with | |
708 | * mmaps of blockdevs which hold live JBD-controlled filesystems. | |
709 | */ | |
710 | struct journal_head *journal_get_descriptor_buffer(journal_t *journal) | |
711 | { | |
712 | struct buffer_head *bh; | |
9c28cbcc | 713 | unsigned int blocknr; |
1da177e4 LT |
714 | int err; |
715 | ||
716 | err = journal_next_log_block(journal, &blocknr); | |
717 | ||
718 | if (err) | |
719 | return NULL; | |
720 | ||
721 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
ecca9af0 JK |
722 | if (!bh) |
723 | return NULL; | |
1da177e4 LT |
724 | lock_buffer(bh); |
725 | memset(bh->b_data, 0, journal->j_blocksize); | |
726 | set_buffer_uptodate(bh); | |
727 | unlock_buffer(bh); | |
728 | BUFFER_TRACE(bh, "return this buffer"); | |
729 | return journal_add_journal_head(bh); | |
730 | } | |
731 | ||
732 | /* | |
733 | * Management for journal control blocks: functions to create and | |
734 | * destroy journal_t structures, and to initialise and read existing | |
735 | * journal blocks from disk. */ | |
736 | ||
737 | /* First: create and setup a journal_t object in memory. We initialise | |
738 | * very few fields yet: that has to wait until we have created the | |
739 | * journal structures from from scratch, or loaded them from disk. */ | |
740 | ||
741 | static journal_t * journal_init_common (void) | |
742 | { | |
743 | journal_t *journal; | |
744 | int err; | |
745 | ||
8c3478a5 | 746 | journal = kzalloc(sizeof(*journal), GFP_KERNEL); |
1da177e4 LT |
747 | if (!journal) |
748 | goto fail; | |
1da177e4 LT |
749 | |
750 | init_waitqueue_head(&journal->j_wait_transaction_locked); | |
751 | init_waitqueue_head(&journal->j_wait_logspace); | |
752 | init_waitqueue_head(&journal->j_wait_done_commit); | |
753 | init_waitqueue_head(&journal->j_wait_checkpoint); | |
754 | init_waitqueue_head(&journal->j_wait_commit); | |
755 | init_waitqueue_head(&journal->j_wait_updates); | |
2c68ee75 | 756 | mutex_init(&journal->j_checkpoint_mutex); |
1da177e4 LT |
757 | spin_lock_init(&journal->j_revoke_lock); |
758 | spin_lock_init(&journal->j_list_lock); | |
759 | spin_lock_init(&journal->j_state_lock); | |
760 | ||
761 | journal->j_commit_interval = (HZ * JBD_DEFAULT_MAX_COMMIT_AGE); | |
762 | ||
763 | /* The journal is marked for error until we succeed with recovery! */ | |
764 | journal->j_flags = JFS_ABORT; | |
765 | ||
766 | /* Set up a default-sized revoke table for the new mount. */ | |
767 | err = journal_init_revoke(journal, JOURNAL_REVOKE_DEFAULT_HASH); | |
768 | if (err) { | |
769 | kfree(journal); | |
770 | goto fail; | |
771 | } | |
772 | return journal; | |
773 | fail: | |
774 | return NULL; | |
775 | } | |
776 | ||
777 | /* journal_init_dev and journal_init_inode: | |
778 | * | |
779 | * Create a journal structure assigned some fixed set of disk blocks to | |
780 | * the journal. We don't actually touch those disk blocks yet, but we | |
781 | * need to set up all of the mapping information to tell the journaling | |
782 | * system where the journal blocks are. | |
783 | * | |
784 | */ | |
785 | ||
786 | /** | |
0cf01f66 | 787 | * journal_t * journal_init_dev() - creates and initialises a journal structure |
1da177e4 LT |
788 | * @bdev: Block device on which to create the journal |
789 | * @fs_dev: Device which hold journalled filesystem for this journal. | |
790 | * @start: Block nr Start of journal. | |
37ed3222 | 791 | * @len: Length of the journal in blocks. |
1da177e4 | 792 | * @blocksize: blocksize of journalling device |
0cf01f66 RD |
793 | * |
794 | * Returns: a newly created journal_t * | |
ae6ddcc5 | 795 | * |
1da177e4 LT |
796 | * journal_init_dev creates a journal which maps a fixed contiguous |
797 | * range of blocks on an arbitrary block device. | |
ae6ddcc5 | 798 | * |
1da177e4 LT |
799 | */ |
800 | journal_t * journal_init_dev(struct block_device *bdev, | |
801 | struct block_device *fs_dev, | |
802 | int start, int len, int blocksize) | |
803 | { | |
804 | journal_t *journal = journal_init_common(); | |
805 | struct buffer_head *bh; | |
806 | int n; | |
807 | ||
808 | if (!journal) | |
809 | return NULL; | |
810 | ||
1da177e4 | 811 | /* journal descriptor can store up to n blocks -bzzz */ |
d1807793 | 812 | journal->j_blocksize = blocksize; |
1da177e4 LT |
813 | n = journal->j_blocksize / sizeof(journal_block_tag_t); |
814 | journal->j_wbufsize = n; | |
815 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
816 | if (!journal->j_wbuf) { | |
25985edc | 817 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
08fc99bf | 818 | __func__); |
ecca9af0 | 819 | goto out_err; |
1da177e4 | 820 | } |
d1807793 ZM |
821 | journal->j_dev = bdev; |
822 | journal->j_fs_dev = fs_dev; | |
823 | journal->j_blk_offset = start; | |
824 | journal->j_maxlen = len; | |
825 | ||
826 | bh = __getblk(journal->j_dev, start, journal->j_blocksize); | |
ecca9af0 JK |
827 | if (!bh) { |
828 | printk(KERN_ERR | |
829 | "%s: Cannot get buffer for journal superblock\n", | |
830 | __func__); | |
831 | goto out_err; | |
832 | } | |
d1807793 ZM |
833 | journal->j_sb_buffer = bh; |
834 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
ecca9af0 | 835 | |
1da177e4 | 836 | return journal; |
ecca9af0 | 837 | out_err: |
7b02bec0 | 838 | kfree(journal->j_wbuf); |
ecca9af0 JK |
839 | kfree(journal); |
840 | return NULL; | |
1da177e4 | 841 | } |
ae6ddcc5 MC |
842 | |
843 | /** | |
1da177e4 LT |
844 | * journal_t * journal_init_inode () - creates a journal which maps to a inode. |
845 | * @inode: An inode to create the journal in | |
ae6ddcc5 | 846 | * |
1da177e4 LT |
847 | * journal_init_inode creates a journal which maps an on-disk inode as |
848 | * the journal. The inode must exist already, must support bmap() and | |
849 | * must have all data blocks preallocated. | |
850 | */ | |
851 | journal_t * journal_init_inode (struct inode *inode) | |
852 | { | |
853 | struct buffer_head *bh; | |
854 | journal_t *journal = journal_init_common(); | |
855 | int err; | |
856 | int n; | |
9c28cbcc | 857 | unsigned int blocknr; |
1da177e4 LT |
858 | |
859 | if (!journal) | |
860 | return NULL; | |
861 | ||
862 | journal->j_dev = journal->j_fs_dev = inode->i_sb->s_bdev; | |
863 | journal->j_inode = inode; | |
864 | jbd_debug(1, | |
865 | "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n", | |
ae6ddcc5 | 866 | journal, inode->i_sb->s_id, inode->i_ino, |
1da177e4 LT |
867 | (long long) inode->i_size, |
868 | inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize); | |
869 | ||
870 | journal->j_maxlen = inode->i_size >> inode->i_sb->s_blocksize_bits; | |
871 | journal->j_blocksize = inode->i_sb->s_blocksize; | |
872 | ||
873 | /* journal descriptor can store up to n blocks -bzzz */ | |
874 | n = journal->j_blocksize / sizeof(journal_block_tag_t); | |
875 | journal->j_wbufsize = n; | |
876 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
877 | if (!journal->j_wbuf) { | |
25985edc | 878 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
08fc99bf | 879 | __func__); |
ecca9af0 | 880 | goto out_err; |
1da177e4 LT |
881 | } |
882 | ||
883 | err = journal_bmap(journal, 0, &blocknr); | |
884 | /* If that failed, give up */ | |
885 | if (err) { | |
3c26bdb4 | 886 | printk(KERN_ERR "%s: Cannot locate journal superblock\n", |
08fc99bf | 887 | __func__); |
ecca9af0 | 888 | goto out_err; |
1da177e4 LT |
889 | } |
890 | ||
891 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
ecca9af0 JK |
892 | if (!bh) { |
893 | printk(KERN_ERR | |
894 | "%s: Cannot get buffer for journal superblock\n", | |
895 | __func__); | |
896 | goto out_err; | |
897 | } | |
1da177e4 LT |
898 | journal->j_sb_buffer = bh; |
899 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
900 | ||
901 | return journal; | |
ecca9af0 | 902 | out_err: |
7b02bec0 | 903 | kfree(journal->j_wbuf); |
ecca9af0 JK |
904 | kfree(journal); |
905 | return NULL; | |
1da177e4 LT |
906 | } |
907 | ||
ae6ddcc5 | 908 | /* |
1da177e4 LT |
909 | * If the journal init or create aborts, we need to mark the journal |
910 | * superblock as being NULL to prevent the journal destroy from writing | |
ae6ddcc5 | 911 | * back a bogus superblock. |
1da177e4 LT |
912 | */ |
913 | static void journal_fail_superblock (journal_t *journal) | |
914 | { | |
915 | struct buffer_head *bh = journal->j_sb_buffer; | |
916 | brelse(bh); | |
917 | journal->j_sb_buffer = NULL; | |
918 | } | |
919 | ||
920 | /* | |
921 | * Given a journal_t structure, initialise the various fields for | |
922 | * startup of a new journaling session. We use this both when creating | |
923 | * a journal, and after recovering an old journal to reset it for | |
924 | * subsequent use. | |
925 | */ | |
926 | ||
927 | static int journal_reset(journal_t *journal) | |
928 | { | |
929 | journal_superblock_t *sb = journal->j_superblock; | |
9c28cbcc | 930 | unsigned int first, last; |
1da177e4 LT |
931 | |
932 | first = be32_to_cpu(sb->s_first); | |
933 | last = be32_to_cpu(sb->s_maxlen); | |
7447a668 | 934 | if (first + JFS_MIN_JOURNAL_BLOCKS > last + 1) { |
9c28cbcc | 935 | printk(KERN_ERR "JBD: Journal too short (blocks %u-%u).\n", |
7447a668 JK |
936 | first, last); |
937 | journal_fail_superblock(journal); | |
938 | return -EINVAL; | |
939 | } | |
1da177e4 LT |
940 | |
941 | journal->j_first = first; | |
942 | journal->j_last = last; | |
943 | ||
944 | journal->j_head = first; | |
945 | journal->j_tail = first; | |
946 | journal->j_free = last - first; | |
947 | ||
948 | journal->j_tail_sequence = journal->j_transaction_sequence; | |
949 | journal->j_commit_sequence = journal->j_transaction_sequence - 1; | |
950 | journal->j_commit_request = journal->j_commit_sequence; | |
951 | ||
952 | journal->j_max_transaction_buffers = journal->j_maxlen / 4; | |
953 | ||
9754e39c JK |
954 | /* |
955 | * As a special case, if the on-disk copy is already marked as needing | |
956 | * no recovery (s_start == 0), then we can safely defer the superblock | |
957 | * update until the next commit by setting JFS_FLUSHED. This avoids | |
958 | * attempting a write to a potential-readonly device. | |
959 | */ | |
960 | if (sb->s_start == 0) { | |
961 | jbd_debug(1,"JBD: Skipping superblock update on recovered sb " | |
962 | "(start %u, seq %d, errno %d)\n", | |
963 | journal->j_tail, journal->j_tail_sequence, | |
964 | journal->j_errno); | |
965 | journal->j_flags |= JFS_FLUSHED; | |
966 | } else { | |
1ce8486d JK |
967 | /* Lock here to make assertions happy... */ |
968 | mutex_lock(&journal->j_checkpoint_mutex); | |
fd2cbd4d JK |
969 | /* |
970 | * Update log tail information. We use WRITE_FUA since new | |
971 | * transaction will start reusing journal space and so we | |
972 | * must make sure information about current log tail is on | |
973 | * disk before that. | |
974 | */ | |
975 | journal_update_sb_log_tail(journal, | |
976 | journal->j_tail_sequence, | |
977 | journal->j_tail, | |
978 | WRITE_FUA); | |
1ce8486d | 979 | mutex_unlock(&journal->j_checkpoint_mutex); |
9754e39c | 980 | } |
97f06784 | 981 | return journal_start_thread(journal); |
1da177e4 LT |
982 | } |
983 | ||
ae6ddcc5 | 984 | /** |
1da177e4 LT |
985 | * int journal_create() - Initialise the new journal file |
986 | * @journal: Journal to create. This structure must have been initialised | |
ae6ddcc5 | 987 | * |
1da177e4 LT |
988 | * Given a journal_t structure which tells us which disk blocks we can |
989 | * use, create a new journal superblock and initialise all of the | |
ae6ddcc5 | 990 | * journal fields from scratch. |
1da177e4 LT |
991 | **/ |
992 | int journal_create(journal_t *journal) | |
993 | { | |
9c28cbcc | 994 | unsigned int blocknr; |
1da177e4 LT |
995 | struct buffer_head *bh; |
996 | journal_superblock_t *sb; | |
997 | int i, err; | |
998 | ||
999 | if (journal->j_maxlen < JFS_MIN_JOURNAL_BLOCKS) { | |
1000 | printk (KERN_ERR "Journal length (%d blocks) too short.\n", | |
1001 | journal->j_maxlen); | |
1002 | journal_fail_superblock(journal); | |
1003 | return -EINVAL; | |
1004 | } | |
1005 | ||
1006 | if (journal->j_inode == NULL) { | |
1007 | /* | |
1008 | * We don't know what block to start at! | |
1009 | */ | |
1010 | printk(KERN_EMERG | |
1011 | "%s: creation of journal on external device!\n", | |
08fc99bf | 1012 | __func__); |
1da177e4 LT |
1013 | BUG(); |
1014 | } | |
1015 | ||
1016 | /* Zero out the entire journal on disk. We cannot afford to | |
1017 | have any blocks on disk beginning with JFS_MAGIC_NUMBER. */ | |
1018 | jbd_debug(1, "JBD: Zeroing out journal blocks...\n"); | |
1019 | for (i = 0; i < journal->j_maxlen; i++) { | |
1020 | err = journal_bmap(journal, i, &blocknr); | |
1021 | if (err) | |
1022 | return err; | |
1023 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
2a0e3388 NK |
1024 | if (unlikely(!bh)) |
1025 | return -ENOMEM; | |
1da177e4 LT |
1026 | lock_buffer(bh); |
1027 | memset (bh->b_data, 0, journal->j_blocksize); | |
1028 | BUFFER_TRACE(bh, "marking dirty"); | |
1029 | mark_buffer_dirty(bh); | |
1030 | BUFFER_TRACE(bh, "marking uptodate"); | |
1031 | set_buffer_uptodate(bh); | |
1032 | unlock_buffer(bh); | |
1033 | __brelse(bh); | |
1034 | } | |
1035 | ||
1036 | sync_blockdev(journal->j_dev); | |
1037 | jbd_debug(1, "JBD: journal cleared.\n"); | |
1038 | ||
1039 | /* OK, fill in the initial static fields in the new superblock */ | |
1040 | sb = journal->j_superblock; | |
1041 | ||
1042 | sb->s_header.h_magic = cpu_to_be32(JFS_MAGIC_NUMBER); | |
1043 | sb->s_header.h_blocktype = cpu_to_be32(JFS_SUPERBLOCK_V2); | |
1044 | ||
1045 | sb->s_blocksize = cpu_to_be32(journal->j_blocksize); | |
1046 | sb->s_maxlen = cpu_to_be32(journal->j_maxlen); | |
1047 | sb->s_first = cpu_to_be32(1); | |
1048 | ||
1049 | journal->j_transaction_sequence = 1; | |
1050 | ||
1051 | journal->j_flags &= ~JFS_ABORT; | |
1052 | journal->j_format_version = 2; | |
1053 | ||
1054 | return journal_reset(journal); | |
1055 | } | |
1056 | ||
fd2cbd4d | 1057 | static void journal_write_superblock(journal_t *journal, int write_op) |
1da177e4 | 1058 | { |
1da177e4 | 1059 | struct buffer_head *bh = journal->j_sb_buffer; |
fd2cbd4d | 1060 | int ret; |
1da177e4 | 1061 | |
fd2cbd4d JK |
1062 | trace_journal_write_superblock(journal, write_op); |
1063 | if (!(journal->j_flags & JFS_BARRIER)) | |
1064 | write_op &= ~(REQ_FUA | REQ_FLUSH); | |
1065 | lock_buffer(bh); | |
dff6825e DW |
1066 | if (buffer_write_io_error(bh)) { |
1067 | char b[BDEVNAME_SIZE]; | |
1068 | /* | |
1069 | * Oh, dear. A previous attempt to write the journal | |
1070 | * superblock failed. This could happen because the | |
1071 | * USB device was yanked out. Or it could happen to | |
1072 | * be a transient write error and maybe the block will | |
1073 | * be remapped. Nothing we can do but to retry the | |
1074 | * write and hope for the best. | |
1075 | */ | |
1076 | printk(KERN_ERR "JBD: previous I/O error detected " | |
1077 | "for journal superblock update for %s.\n", | |
1078 | journal_dev_name(journal, b)); | |
1079 | clear_buffer_write_io_error(bh); | |
1080 | set_buffer_uptodate(bh); | |
1081 | } | |
1082 | ||
fd2cbd4d JK |
1083 | get_bh(bh); |
1084 | bh->b_end_io = end_buffer_write_sync; | |
1085 | ret = submit_bh(write_op, bh); | |
1086 | wait_on_buffer(bh); | |
9754e39c | 1087 | if (buffer_write_io_error(bh)) { |
9754e39c JK |
1088 | clear_buffer_write_io_error(bh); |
1089 | set_buffer_uptodate(bh); | |
fd2cbd4d JK |
1090 | ret = -EIO; |
1091 | } | |
1092 | if (ret) { | |
1093 | char b[BDEVNAME_SIZE]; | |
1094 | printk(KERN_ERR "JBD: Error %d detected " | |
1095 | "when updating journal superblock for %s.\n", | |
1096 | ret, journal_dev_name(journal, b)); | |
9754e39c JK |
1097 | } |
1098 | } | |
1099 | ||
1100 | /** | |
1101 | * journal_update_sb_log_tail() - Update log tail in journal sb on disk. | |
1102 | * @journal: The journal to update. | |
fd2cbd4d JK |
1103 | * @tail_tid: TID of the new transaction at the tail of the log |
1104 | * @tail_block: The first block of the transaction at the tail of the log | |
1105 | * @write_op: With which operation should we write the journal sb | |
9754e39c JK |
1106 | * |
1107 | * Update a journal's superblock information about log tail and write it to | |
1108 | * disk, waiting for the IO to complete. | |
1109 | */ | |
fd2cbd4d JK |
1110 | void journal_update_sb_log_tail(journal_t *journal, tid_t tail_tid, |
1111 | unsigned int tail_block, int write_op) | |
9754e39c JK |
1112 | { |
1113 | journal_superblock_t *sb = journal->j_superblock; | |
1114 | ||
1ce8486d | 1115 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); |
fd2cbd4d JK |
1116 | jbd_debug(1,"JBD: updating superblock (start %u, seq %u)\n", |
1117 | tail_block, tail_tid); | |
1da177e4 | 1118 | |
fd2cbd4d JK |
1119 | sb->s_sequence = cpu_to_be32(tail_tid); |
1120 | sb->s_start = cpu_to_be32(tail_block); | |
1da177e4 | 1121 | |
fd2cbd4d | 1122 | journal_write_superblock(journal, write_op); |
1da177e4 | 1123 | |
9754e39c JK |
1124 | /* Log is no longer empty */ |
1125 | spin_lock(&journal->j_state_lock); | |
1126 | WARN_ON(!sb->s_sequence); | |
1127 | journal->j_flags &= ~JFS_FLUSHED; | |
1128 | spin_unlock(&journal->j_state_lock); | |
1129 | } | |
1130 | ||
1131 | /** | |
1132 | * mark_journal_empty() - Mark on disk journal as empty. | |
1133 | * @journal: The journal to update. | |
1134 | * | |
1135 | * Update a journal's dynamic superblock fields to show that journal is empty. | |
1136 | * Write updated superblock to disk waiting for IO to complete. | |
1137 | */ | |
1138 | static void mark_journal_empty(journal_t *journal) | |
1139 | { | |
1140 | journal_superblock_t *sb = journal->j_superblock; | |
1da177e4 | 1141 | |
1ce8486d | 1142 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); |
1da177e4 | 1143 | spin_lock(&journal->j_state_lock); |
2e84f264 JK |
1144 | /* Is it already empty? */ |
1145 | if (sb->s_start == 0) { | |
1146 | spin_unlock(&journal->j_state_lock); | |
1147 | return; | |
1148 | } | |
9754e39c JK |
1149 | jbd_debug(1, "JBD: Marking journal as empty (seq %d)\n", |
1150 | journal->j_tail_sequence); | |
1151 | ||
1152 | sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); | |
1153 | sb->s_start = cpu_to_be32(0); | |
1154 | spin_unlock(&journal->j_state_lock); | |
1155 | ||
fd2cbd4d | 1156 | journal_write_superblock(journal, WRITE_FUA); |
9754e39c JK |
1157 | |
1158 | spin_lock(&journal->j_state_lock); | |
1159 | /* Log is empty */ | |
1160 | journal->j_flags |= JFS_FLUSHED; | |
1da177e4 LT |
1161 | spin_unlock(&journal->j_state_lock); |
1162 | } | |
1163 | ||
9754e39c JK |
1164 | /** |
1165 | * journal_update_sb_errno() - Update error in the journal. | |
1166 | * @journal: The journal to update. | |
1167 | * | |
1168 | * Update a journal's errno. Write updated superblock to disk waiting for IO | |
1169 | * to complete. | |
1170 | */ | |
1171 | static void journal_update_sb_errno(journal_t *journal) | |
1172 | { | |
1173 | journal_superblock_t *sb = journal->j_superblock; | |
1174 | ||
1175 | spin_lock(&journal->j_state_lock); | |
1176 | jbd_debug(1, "JBD: updating superblock error (errno %d)\n", | |
1177 | journal->j_errno); | |
1178 | sb->s_errno = cpu_to_be32(journal->j_errno); | |
1179 | spin_unlock(&journal->j_state_lock); | |
1180 | ||
fd2cbd4d | 1181 | journal_write_superblock(journal, WRITE_SYNC); |
9754e39c JK |
1182 | } |
1183 | ||
1da177e4 LT |
1184 | /* |
1185 | * Read the superblock for a given journal, performing initial | |
1186 | * validation of the format. | |
1187 | */ | |
1188 | ||
1189 | static int journal_get_superblock(journal_t *journal) | |
1190 | { | |
1191 | struct buffer_head *bh; | |
1192 | journal_superblock_t *sb; | |
1193 | int err = -EIO; | |
1194 | ||
1195 | bh = journal->j_sb_buffer; | |
1196 | ||
1197 | J_ASSERT(bh != NULL); | |
1198 | if (!buffer_uptodate(bh)) { | |
1199 | ll_rw_block(READ, 1, &bh); | |
1200 | wait_on_buffer(bh); | |
1201 | if (!buffer_uptodate(bh)) { | |
1202 | printk (KERN_ERR | |
1203 | "JBD: IO error reading journal superblock\n"); | |
1204 | goto out; | |
1205 | } | |
1206 | } | |
1207 | ||
1208 | sb = journal->j_superblock; | |
1209 | ||
1210 | err = -EINVAL; | |
1211 | ||
1212 | if (sb->s_header.h_magic != cpu_to_be32(JFS_MAGIC_NUMBER) || | |
1213 | sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) { | |
1214 | printk(KERN_WARNING "JBD: no valid journal superblock found\n"); | |
1215 | goto out; | |
1216 | } | |
1217 | ||
1218 | switch(be32_to_cpu(sb->s_header.h_blocktype)) { | |
1219 | case JFS_SUPERBLOCK_V1: | |
1220 | journal->j_format_version = 1; | |
1221 | break; | |
1222 | case JFS_SUPERBLOCK_V2: | |
1223 | journal->j_format_version = 2; | |
1224 | break; | |
1225 | default: | |
1226 | printk(KERN_WARNING "JBD: unrecognised superblock format ID\n"); | |
1227 | goto out; | |
1228 | } | |
1229 | ||
1230 | if (be32_to_cpu(sb->s_maxlen) < journal->j_maxlen) | |
1231 | journal->j_maxlen = be32_to_cpu(sb->s_maxlen); | |
1232 | else if (be32_to_cpu(sb->s_maxlen) > journal->j_maxlen) { | |
1233 | printk (KERN_WARNING "JBD: journal file too short\n"); | |
1234 | goto out; | |
1235 | } | |
1236 | ||
8762202d EG |
1237 | if (be32_to_cpu(sb->s_first) == 0 || |
1238 | be32_to_cpu(sb->s_first) >= journal->j_maxlen) { | |
1239 | printk(KERN_WARNING | |
1240 | "JBD: Invalid start block of journal: %u\n", | |
1241 | be32_to_cpu(sb->s_first)); | |
1242 | goto out; | |
1243 | } | |
1244 | ||
1da177e4 LT |
1245 | return 0; |
1246 | ||
1247 | out: | |
1248 | journal_fail_superblock(journal); | |
1249 | return err; | |
1250 | } | |
1251 | ||
1252 | /* | |
1253 | * Load the on-disk journal superblock and read the key fields into the | |
1254 | * journal_t. | |
1255 | */ | |
1256 | ||
1257 | static int load_superblock(journal_t *journal) | |
1258 | { | |
1259 | int err; | |
1260 | journal_superblock_t *sb; | |
1261 | ||
1262 | err = journal_get_superblock(journal); | |
1263 | if (err) | |
1264 | return err; | |
1265 | ||
1266 | sb = journal->j_superblock; | |
1267 | ||
1268 | journal->j_tail_sequence = be32_to_cpu(sb->s_sequence); | |
1269 | journal->j_tail = be32_to_cpu(sb->s_start); | |
1270 | journal->j_first = be32_to_cpu(sb->s_first); | |
1271 | journal->j_last = be32_to_cpu(sb->s_maxlen); | |
1272 | journal->j_errno = be32_to_cpu(sb->s_errno); | |
1273 | ||
1274 | return 0; | |
1275 | } | |
1276 | ||
1277 | ||
1278 | /** | |
1279 | * int journal_load() - Read journal from disk. | |
1280 | * @journal: Journal to act on. | |
ae6ddcc5 | 1281 | * |
1da177e4 LT |
1282 | * Given a journal_t structure which tells us which disk blocks contain |
1283 | * a journal, read the journal from disk to initialise the in-memory | |
1284 | * structures. | |
1285 | */ | |
1286 | int journal_load(journal_t *journal) | |
1287 | { | |
1288 | int err; | |
ea817398 | 1289 | journal_superblock_t *sb; |
1da177e4 LT |
1290 | |
1291 | err = load_superblock(journal); | |
1292 | if (err) | |
1293 | return err; | |
1294 | ||
ea817398 | 1295 | sb = journal->j_superblock; |
1da177e4 LT |
1296 | /* If this is a V2 superblock, then we have to check the |
1297 | * features flags on it. */ | |
1298 | ||
1299 | if (journal->j_format_version >= 2) { | |
1da177e4 LT |
1300 | if ((sb->s_feature_ro_compat & |
1301 | ~cpu_to_be32(JFS_KNOWN_ROCOMPAT_FEATURES)) || | |
1302 | (sb->s_feature_incompat & | |
1303 | ~cpu_to_be32(JFS_KNOWN_INCOMPAT_FEATURES))) { | |
1304 | printk (KERN_WARNING | |
1305 | "JBD: Unrecognised features on journal\n"); | |
1306 | return -EINVAL; | |
1307 | } | |
1308 | } | |
1309 | ||
1310 | /* Let the recovery code check whether it needs to recover any | |
1311 | * data from the journal. */ | |
1312 | if (journal_recover(journal)) | |
1313 | goto recovery_error; | |
1314 | ||
1315 | /* OK, we've finished with the dynamic journal bits: | |
1316 | * reinitialise the dynamic contents of the superblock in memory | |
1317 | * and reset them on disk. */ | |
1318 | if (journal_reset(journal)) | |
1319 | goto recovery_error; | |
1320 | ||
1321 | journal->j_flags &= ~JFS_ABORT; | |
1322 | journal->j_flags |= JFS_LOADED; | |
1323 | return 0; | |
1324 | ||
1325 | recovery_error: | |
1326 | printk (KERN_WARNING "JBD: recovery failed\n"); | |
1327 | return -EIO; | |
1328 | } | |
1329 | ||
1330 | /** | |
1331 | * void journal_destroy() - Release a journal_t structure. | |
1332 | * @journal: Journal to act on. | |
1333 | * | |
1334 | * Release a journal_t structure once it is no longer in use by the | |
1335 | * journaled object. | |
4afe9785 | 1336 | * Return <0 if we couldn't clean up the journal. |
1da177e4 | 1337 | */ |
4afe9785 | 1338 | int journal_destroy(journal_t *journal) |
1da177e4 | 1339 | { |
4afe9785 HK |
1340 | int err = 0; |
1341 | ||
03f4d804 | 1342 | |
1da177e4 LT |
1343 | /* Wait for the commit thread to wake up and die. */ |
1344 | journal_kill_thread(journal); | |
1345 | ||
1346 | /* Force a final log commit */ | |
1347 | if (journal->j_running_transaction) | |
1348 | journal_commit_transaction(journal); | |
1349 | ||
1350 | /* Force any old transactions to disk */ | |
1351 | ||
1ce8486d JK |
1352 | /* We cannot race with anybody but must keep assertions happy */ |
1353 | mutex_lock(&journal->j_checkpoint_mutex); | |
1da177e4 LT |
1354 | /* Totally anal locking here... */ |
1355 | spin_lock(&journal->j_list_lock); | |
1356 | while (journal->j_checkpoint_transactions != NULL) { | |
1357 | spin_unlock(&journal->j_list_lock); | |
1358 | log_do_checkpoint(journal); | |
1359 | spin_lock(&journal->j_list_lock); | |
1360 | } | |
1361 | ||
1362 | J_ASSERT(journal->j_running_transaction == NULL); | |
1363 | J_ASSERT(journal->j_committing_transaction == NULL); | |
1364 | J_ASSERT(journal->j_checkpoint_transactions == NULL); | |
1365 | spin_unlock(&journal->j_list_lock); | |
1366 | ||
1da177e4 | 1367 | if (journal->j_sb_buffer) { |
4afe9785 | 1368 | if (!is_journal_aborted(journal)) { |
4afe9785 HK |
1369 | journal->j_tail_sequence = |
1370 | ++journal->j_transaction_sequence; | |
9754e39c JK |
1371 | mark_journal_empty(journal); |
1372 | } else | |
4afe9785 | 1373 | err = -EIO; |
1da177e4 LT |
1374 | brelse(journal->j_sb_buffer); |
1375 | } | |
1ce8486d | 1376 | mutex_unlock(&journal->j_checkpoint_mutex); |
1da177e4 LT |
1377 | |
1378 | if (journal->j_inode) | |
1379 | iput(journal->j_inode); | |
1380 | if (journal->j_revoke) | |
1381 | journal_destroy_revoke(journal); | |
1382 | kfree(journal->j_wbuf); | |
1383 | kfree(journal); | |
4afe9785 HK |
1384 | |
1385 | return err; | |
1da177e4 LT |
1386 | } |
1387 | ||
1388 | ||
1389 | /** | |
1390 | *int journal_check_used_features () - Check if features specified are used. | |
1391 | * @journal: Journal to check. | |
1392 | * @compat: bitmask of compatible features | |
1393 | * @ro: bitmask of features that force read-only mount | |
1394 | * @incompat: bitmask of incompatible features | |
ae6ddcc5 | 1395 | * |
1da177e4 | 1396 | * Check whether the journal uses all of a given set of |
ae6ddcc5 | 1397 | * features. Return true (non-zero) if it does. |
1da177e4 LT |
1398 | **/ |
1399 | ||
1400 | int journal_check_used_features (journal_t *journal, unsigned long compat, | |
1401 | unsigned long ro, unsigned long incompat) | |
1402 | { | |
1403 | journal_superblock_t *sb; | |
1404 | ||
1405 | if (!compat && !ro && !incompat) | |
1406 | return 1; | |
1407 | if (journal->j_format_version == 1) | |
1408 | return 0; | |
1409 | ||
1410 | sb = journal->j_superblock; | |
1411 | ||
1412 | if (((be32_to_cpu(sb->s_feature_compat) & compat) == compat) && | |
1413 | ((be32_to_cpu(sb->s_feature_ro_compat) & ro) == ro) && | |
1414 | ((be32_to_cpu(sb->s_feature_incompat) & incompat) == incompat)) | |
1415 | return 1; | |
1416 | ||
1417 | return 0; | |
1418 | } | |
1419 | ||
1420 | /** | |
1421 | * int journal_check_available_features() - Check feature set in journalling layer | |
1422 | * @journal: Journal to check. | |
1423 | * @compat: bitmask of compatible features | |
1424 | * @ro: bitmask of features that force read-only mount | |
1425 | * @incompat: bitmask of incompatible features | |
ae6ddcc5 | 1426 | * |
1da177e4 LT |
1427 | * Check whether the journaling code supports the use of |
1428 | * all of a given set of features on this journal. Return true | |
1429 | * (non-zero) if it can. */ | |
1430 | ||
1431 | int journal_check_available_features (journal_t *journal, unsigned long compat, | |
1432 | unsigned long ro, unsigned long incompat) | |
1433 | { | |
1da177e4 LT |
1434 | if (!compat && !ro && !incompat) |
1435 | return 1; | |
1436 | ||
1da177e4 LT |
1437 | /* We can support any known requested features iff the |
1438 | * superblock is in version 2. Otherwise we fail to support any | |
1439 | * extended sb features. */ | |
1440 | ||
1441 | if (journal->j_format_version != 2) | |
1442 | return 0; | |
1443 | ||
1444 | if ((compat & JFS_KNOWN_COMPAT_FEATURES) == compat && | |
1445 | (ro & JFS_KNOWN_ROCOMPAT_FEATURES) == ro && | |
1446 | (incompat & JFS_KNOWN_INCOMPAT_FEATURES) == incompat) | |
1447 | return 1; | |
1448 | ||
1449 | return 0; | |
1450 | } | |
1451 | ||
1452 | /** | |
1453 | * int journal_set_features () - Mark a given journal feature in the superblock | |
1454 | * @journal: Journal to act on. | |
1455 | * @compat: bitmask of compatible features | |
1456 | * @ro: bitmask of features that force read-only mount | |
1457 | * @incompat: bitmask of incompatible features | |
1458 | * | |
1459 | * Mark a given journal feature as present on the | |
ae6ddcc5 | 1460 | * superblock. Returns true if the requested features could be set. |
1da177e4 LT |
1461 | * |
1462 | */ | |
1463 | ||
1464 | int journal_set_features (journal_t *journal, unsigned long compat, | |
1465 | unsigned long ro, unsigned long incompat) | |
1466 | { | |
1467 | journal_superblock_t *sb; | |
1468 | ||
1469 | if (journal_check_used_features(journal, compat, ro, incompat)) | |
1470 | return 1; | |
1471 | ||
1472 | if (!journal_check_available_features(journal, compat, ro, incompat)) | |
1473 | return 0; | |
1474 | ||
1475 | jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n", | |
1476 | compat, ro, incompat); | |
1477 | ||
1478 | sb = journal->j_superblock; | |
1479 | ||
1480 | sb->s_feature_compat |= cpu_to_be32(compat); | |
1481 | sb->s_feature_ro_compat |= cpu_to_be32(ro); | |
1482 | sb->s_feature_incompat |= cpu_to_be32(incompat); | |
1483 | ||
1484 | return 1; | |
1485 | } | |
1486 | ||
1487 | ||
1488 | /** | |
1489 | * int journal_update_format () - Update on-disk journal structure. | |
1490 | * @journal: Journal to act on. | |
1491 | * | |
1492 | * Given an initialised but unloaded journal struct, poke about in the | |
1493 | * on-disk structure to update it to the most recent supported version. | |
1494 | */ | |
1495 | int journal_update_format (journal_t *journal) | |
1496 | { | |
1497 | journal_superblock_t *sb; | |
1498 | int err; | |
1499 | ||
1500 | err = journal_get_superblock(journal); | |
1501 | if (err) | |
1502 | return err; | |
1503 | ||
1504 | sb = journal->j_superblock; | |
1505 | ||
1506 | switch (be32_to_cpu(sb->s_header.h_blocktype)) { | |
1507 | case JFS_SUPERBLOCK_V2: | |
1508 | return 0; | |
1509 | case JFS_SUPERBLOCK_V1: | |
1510 | return journal_convert_superblock_v1(journal, sb); | |
1511 | default: | |
1512 | break; | |
1513 | } | |
1514 | return -EINVAL; | |
1515 | } | |
1516 | ||
1517 | static int journal_convert_superblock_v1(journal_t *journal, | |
1518 | journal_superblock_t *sb) | |
1519 | { | |
1520 | int offset, blocksize; | |
1521 | struct buffer_head *bh; | |
1522 | ||
1523 | printk(KERN_WARNING | |
1524 | "JBD: Converting superblock from version 1 to 2.\n"); | |
1525 | ||
1526 | /* Pre-initialise new fields to zero */ | |
1527 | offset = ((char *) &(sb->s_feature_compat)) - ((char *) sb); | |
1528 | blocksize = be32_to_cpu(sb->s_blocksize); | |
1529 | memset(&sb->s_feature_compat, 0, blocksize-offset); | |
1530 | ||
1531 | sb->s_nr_users = cpu_to_be32(1); | |
1532 | sb->s_header.h_blocktype = cpu_to_be32(JFS_SUPERBLOCK_V2); | |
1533 | journal->j_format_version = 2; | |
1534 | ||
1535 | bh = journal->j_sb_buffer; | |
1536 | BUFFER_TRACE(bh, "marking dirty"); | |
1537 | mark_buffer_dirty(bh); | |
1538 | sync_dirty_buffer(bh); | |
1539 | return 0; | |
1540 | } | |
1541 | ||
1542 | ||
1543 | /** | |
1544 | * int journal_flush () - Flush journal | |
1545 | * @journal: Journal to act on. | |
ae6ddcc5 | 1546 | * |
1da177e4 LT |
1547 | * Flush all data for a given journal to disk and empty the journal. |
1548 | * Filesystems can use this when remounting readonly to ensure that | |
1549 | * recovery does not need to happen on remount. | |
1550 | */ | |
1551 | ||
1552 | int journal_flush(journal_t *journal) | |
1553 | { | |
1554 | int err = 0; | |
1555 | transaction_t *transaction = NULL; | |
1da177e4 LT |
1556 | |
1557 | spin_lock(&journal->j_state_lock); | |
1558 | ||
1559 | /* Force everything buffered to the log... */ | |
1560 | if (journal->j_running_transaction) { | |
1561 | transaction = journal->j_running_transaction; | |
1562 | __log_start_commit(journal, transaction->t_tid); | |
1563 | } else if (journal->j_committing_transaction) | |
1564 | transaction = journal->j_committing_transaction; | |
1565 | ||
1566 | /* Wait for the log commit to complete... */ | |
1567 | if (transaction) { | |
1568 | tid_t tid = transaction->t_tid; | |
1569 | ||
1570 | spin_unlock(&journal->j_state_lock); | |
1571 | log_wait_commit(journal, tid); | |
1572 | } else { | |
1573 | spin_unlock(&journal->j_state_lock); | |
1574 | } | |
1575 | ||
1576 | /* ...and flush everything in the log out to disk. */ | |
1577 | spin_lock(&journal->j_list_lock); | |
1578 | while (!err && journal->j_checkpoint_transactions != NULL) { | |
1579 | spin_unlock(&journal->j_list_lock); | |
4afe9785 | 1580 | mutex_lock(&journal->j_checkpoint_mutex); |
1da177e4 | 1581 | err = log_do_checkpoint(journal); |
4afe9785 | 1582 | mutex_unlock(&journal->j_checkpoint_mutex); |
1da177e4 LT |
1583 | spin_lock(&journal->j_list_lock); |
1584 | } | |
1585 | spin_unlock(&journal->j_list_lock); | |
4afe9785 HK |
1586 | |
1587 | if (is_journal_aborted(journal)) | |
1588 | return -EIO; | |
1589 | ||
1ce8486d | 1590 | mutex_lock(&journal->j_checkpoint_mutex); |
1da177e4 LT |
1591 | cleanup_journal_tail(journal); |
1592 | ||
1593 | /* Finally, mark the journal as really needing no recovery. | |
1594 | * This sets s_start==0 in the underlying superblock, which is | |
1595 | * the magic code for a fully-recovered superblock. Any future | |
1596 | * commits of data to the journal will restore the current | |
1597 | * s_start value. */ | |
9754e39c | 1598 | mark_journal_empty(journal); |
1ce8486d | 1599 | mutex_unlock(&journal->j_checkpoint_mutex); |
1da177e4 | 1600 | spin_lock(&journal->j_state_lock); |
1da177e4 LT |
1601 | J_ASSERT(!journal->j_running_transaction); |
1602 | J_ASSERT(!journal->j_committing_transaction); | |
1603 | J_ASSERT(!journal->j_checkpoint_transactions); | |
1604 | J_ASSERT(journal->j_head == journal->j_tail); | |
1605 | J_ASSERT(journal->j_tail_sequence == journal->j_transaction_sequence); | |
1606 | spin_unlock(&journal->j_state_lock); | |
4afe9785 | 1607 | return 0; |
1da177e4 LT |
1608 | } |
1609 | ||
1610 | /** | |
1611 | * int journal_wipe() - Wipe journal contents | |
1612 | * @journal: Journal to act on. | |
1613 | * @write: flag (see below) | |
ae6ddcc5 | 1614 | * |
1da177e4 LT |
1615 | * Wipe out all of the contents of a journal, safely. This will produce |
1616 | * a warning if the journal contains any valid recovery information. | |
1617 | * Must be called between journal_init_*() and journal_load(). | |
1618 | * | |
1619 | * If 'write' is non-zero, then we wipe out the journal on disk; otherwise | |
1620 | * we merely suppress recovery. | |
1621 | */ | |
1622 | ||
1623 | int journal_wipe(journal_t *journal, int write) | |
1624 | { | |
1da177e4 LT |
1625 | int err = 0; |
1626 | ||
1627 | J_ASSERT (!(journal->j_flags & JFS_LOADED)); | |
1628 | ||
1629 | err = load_superblock(journal); | |
1630 | if (err) | |
1631 | return err; | |
1632 | ||
1da177e4 LT |
1633 | if (!journal->j_tail) |
1634 | goto no_recovery; | |
1635 | ||
1636 | printk (KERN_WARNING "JBD: %s recovery information on journal\n", | |
1637 | write ? "Clearing" : "Ignoring"); | |
1638 | ||
1639 | err = journal_skip_recovery(journal); | |
1ce8486d JK |
1640 | if (write) { |
1641 | /* Lock to make assertions happy... */ | |
1642 | mutex_lock(&journal->j_checkpoint_mutex); | |
9754e39c | 1643 | mark_journal_empty(journal); |
1ce8486d JK |
1644 | mutex_unlock(&journal->j_checkpoint_mutex); |
1645 | } | |
1da177e4 LT |
1646 | |
1647 | no_recovery: | |
1648 | return err; | |
1649 | } | |
1650 | ||
1651 | /* | |
1652 | * journal_dev_name: format a character string to describe on what | |
1653 | * device this journal is present. | |
1654 | */ | |
1655 | ||
022a4a7b | 1656 | static const char *journal_dev_name(journal_t *journal, char *buffer) |
1da177e4 LT |
1657 | { |
1658 | struct block_device *bdev; | |
1659 | ||
1660 | if (journal->j_inode) | |
1661 | bdev = journal->j_inode->i_sb->s_bdev; | |
1662 | else | |
1663 | bdev = journal->j_dev; | |
1664 | ||
1665 | return bdevname(bdev, buffer); | |
1666 | } | |
1667 | ||
1668 | /* | |
1669 | * Journal abort has very specific semantics, which we describe | |
ae6ddcc5 | 1670 | * for journal abort. |
1da177e4 LT |
1671 | * |
1672 | * Two internal function, which provide abort to te jbd layer | |
1673 | * itself are here. | |
1674 | */ | |
1675 | ||
1676 | /* | |
1677 | * Quick version for internal journal use (doesn't lock the journal). | |
1678 | * Aborts hard --- we mark the abort as occurred, but do _nothing_ else, | |
1679 | * and don't attempt to make any other journal updates. | |
1680 | */ | |
53308383 | 1681 | static void __journal_abort_hard(journal_t *journal) |
1da177e4 LT |
1682 | { |
1683 | transaction_t *transaction; | |
1684 | char b[BDEVNAME_SIZE]; | |
1685 | ||
1686 | if (journal->j_flags & JFS_ABORT) | |
1687 | return; | |
1688 | ||
1689 | printk(KERN_ERR "Aborting journal on device %s.\n", | |
1690 | journal_dev_name(journal, b)); | |
1691 | ||
1692 | spin_lock(&journal->j_state_lock); | |
1693 | journal->j_flags |= JFS_ABORT; | |
1694 | transaction = journal->j_running_transaction; | |
1695 | if (transaction) | |
1696 | __log_start_commit(journal, transaction->t_tid); | |
1697 | spin_unlock(&journal->j_state_lock); | |
1698 | } | |
1699 | ||
1700 | /* Soft abort: record the abort error status in the journal superblock, | |
1701 | * but don't do any other IO. */ | |
022a4a7b | 1702 | static void __journal_abort_soft (journal_t *journal, int errno) |
1da177e4 LT |
1703 | { |
1704 | if (journal->j_flags & JFS_ABORT) | |
1705 | return; | |
1706 | ||
1707 | if (!journal->j_errno) | |
1708 | journal->j_errno = errno; | |
1709 | ||
1710 | __journal_abort_hard(journal); | |
1711 | ||
1712 | if (errno) | |
9754e39c | 1713 | journal_update_sb_errno(journal); |
1da177e4 LT |
1714 | } |
1715 | ||
1716 | /** | |
1717 | * void journal_abort () - Shutdown the journal immediately. | |
1718 | * @journal: the journal to shutdown. | |
1719 | * @errno: an error number to record in the journal indicating | |
1720 | * the reason for the shutdown. | |
1721 | * | |
1722 | * Perform a complete, immediate shutdown of the ENTIRE | |
1723 | * journal (not of a single transaction). This operation cannot be | |
1724 | * undone without closing and reopening the journal. | |
ae6ddcc5 | 1725 | * |
1da177e4 LT |
1726 | * The journal_abort function is intended to support higher level error |
1727 | * recovery mechanisms such as the ext2/ext3 remount-readonly error | |
1728 | * mode. | |
1729 | * | |
1730 | * Journal abort has very specific semantics. Any existing dirty, | |
1731 | * unjournaled buffers in the main filesystem will still be written to | |
1732 | * disk by bdflush, but the journaling mechanism will be suspended | |
1733 | * immediately and no further transaction commits will be honoured. | |
1734 | * | |
1735 | * Any dirty, journaled buffers will be written back to disk without | |
1736 | * hitting the journal. Atomicity cannot be guaranteed on an aborted | |
1737 | * filesystem, but we _do_ attempt to leave as much data as possible | |
1738 | * behind for fsck to use for cleanup. | |
1739 | * | |
1740 | * Any attempt to get a new transaction handle on a journal which is in | |
1741 | * ABORT state will just result in an -EROFS error return. A | |
1742 | * journal_stop on an existing handle will return -EIO if we have | |
1743 | * entered abort state during the update. | |
1744 | * | |
1745 | * Recursive transactions are not disturbed by journal abort until the | |
1746 | * final journal_stop, which will receive the -EIO error. | |
1747 | * | |
1748 | * Finally, the journal_abort call allows the caller to supply an errno | |
1749 | * which will be recorded (if possible) in the journal superblock. This | |
1750 | * allows a client to record failure conditions in the middle of a | |
1751 | * transaction without having to complete the transaction to record the | |
1752 | * failure to disk. ext3_error, for example, now uses this | |
1753 | * functionality. | |
1754 | * | |
1755 | * Errors which originate from within the journaling layer will NOT | |
1756 | * supply an errno; a null errno implies that absolutely no further | |
1757 | * writes are done to the journal (unless there are any already in | |
1758 | * progress). | |
ae6ddcc5 | 1759 | * |
1da177e4 LT |
1760 | */ |
1761 | ||
1762 | void journal_abort(journal_t *journal, int errno) | |
1763 | { | |
1764 | __journal_abort_soft(journal, errno); | |
1765 | } | |
1766 | ||
ae6ddcc5 | 1767 | /** |
1da177e4 LT |
1768 | * int journal_errno () - returns the journal's error state. |
1769 | * @journal: journal to examine. | |
1770 | * | |
1771 | * This is the errno numbet set with journal_abort(), the last | |
1772 | * time the journal was mounted - if the journal was stopped | |
1773 | * without calling abort this will be 0. | |
1774 | * | |
1775 | * If the journal has been aborted on this mount time -EROFS will | |
1776 | * be returned. | |
1777 | */ | |
1778 | int journal_errno(journal_t *journal) | |
1779 | { | |
1780 | int err; | |
1781 | ||
1782 | spin_lock(&journal->j_state_lock); | |
1783 | if (journal->j_flags & JFS_ABORT) | |
1784 | err = -EROFS; | |
1785 | else | |
1786 | err = journal->j_errno; | |
1787 | spin_unlock(&journal->j_state_lock); | |
1788 | return err; | |
1789 | } | |
1790 | ||
ae6ddcc5 | 1791 | /** |
1da177e4 LT |
1792 | * int journal_clear_err () - clears the journal's error state |
1793 | * @journal: journal to act on. | |
1794 | * | |
1795 | * An error must be cleared or Acked to take a FS out of readonly | |
1796 | * mode. | |
1797 | */ | |
1798 | int journal_clear_err(journal_t *journal) | |
1799 | { | |
1800 | int err = 0; | |
1801 | ||
1802 | spin_lock(&journal->j_state_lock); | |
1803 | if (journal->j_flags & JFS_ABORT) | |
1804 | err = -EROFS; | |
1805 | else | |
1806 | journal->j_errno = 0; | |
1807 | spin_unlock(&journal->j_state_lock); | |
1808 | return err; | |
1809 | } | |
1810 | ||
ae6ddcc5 | 1811 | /** |
1da177e4 LT |
1812 | * void journal_ack_err() - Ack journal err. |
1813 | * @journal: journal to act on. | |
1814 | * | |
1815 | * An error must be cleared or Acked to take a FS out of readonly | |
1816 | * mode. | |
1817 | */ | |
1818 | void journal_ack_err(journal_t *journal) | |
1819 | { | |
1820 | spin_lock(&journal->j_state_lock); | |
1821 | if (journal->j_errno) | |
1822 | journal->j_flags |= JFS_ACK_ERR; | |
1823 | spin_unlock(&journal->j_state_lock); | |
1824 | } | |
1825 | ||
1826 | int journal_blocks_per_page(struct inode *inode) | |
1827 | { | |
1828 | return 1 << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
1829 | } | |
1830 | ||
1da177e4 LT |
1831 | /* |
1832 | * Journal_head storage management | |
1833 | */ | |
e18b890b | 1834 | static struct kmem_cache *journal_head_cache; |
1da177e4 LT |
1835 | #ifdef CONFIG_JBD_DEBUG |
1836 | static atomic_t nr_journal_heads = ATOMIC_INIT(0); | |
1837 | #endif | |
1838 | ||
1839 | static int journal_init_journal_head_cache(void) | |
1840 | { | |
1841 | int retval; | |
1842 | ||
1076d17a | 1843 | J_ASSERT(journal_head_cache == NULL); |
1da177e4 LT |
1844 | journal_head_cache = kmem_cache_create("journal_head", |
1845 | sizeof(struct journal_head), | |
1846 | 0, /* offset */ | |
e12ba74d | 1847 | SLAB_TEMPORARY, /* flags */ |
20c2df83 | 1848 | NULL); /* ctor */ |
1da177e4 | 1849 | retval = 0; |
1076d17a | 1850 | if (!journal_head_cache) { |
1da177e4 LT |
1851 | retval = -ENOMEM; |
1852 | printk(KERN_EMERG "JBD: no memory for journal_head cache\n"); | |
1853 | } | |
1854 | return retval; | |
1855 | } | |
1856 | ||
1857 | static void journal_destroy_journal_head_cache(void) | |
1858 | { | |
3850f7a5 DG |
1859 | if (journal_head_cache) { |
1860 | kmem_cache_destroy(journal_head_cache); | |
1861 | journal_head_cache = NULL; | |
1862 | } | |
1da177e4 LT |
1863 | } |
1864 | ||
1865 | /* | |
1866 | * journal_head splicing and dicing | |
1867 | */ | |
1868 | static struct journal_head *journal_alloc_journal_head(void) | |
1869 | { | |
1870 | struct journal_head *ret; | |
1da177e4 LT |
1871 | |
1872 | #ifdef CONFIG_JBD_DEBUG | |
1873 | atomic_inc(&nr_journal_heads); | |
1874 | #endif | |
8bb9da94 | 1875 | ret = kmem_cache_zalloc(journal_head_cache, GFP_NOFS); |
c80544dc | 1876 | if (ret == NULL) { |
1da177e4 | 1877 | jbd_debug(1, "out of memory for journal_head\n"); |
f81e3d45 NK |
1878 | printk_ratelimited(KERN_NOTICE "ENOMEM in %s, retrying.\n", |
1879 | __func__); | |
1880 | ||
c80544dc | 1881 | while (ret == NULL) { |
1da177e4 | 1882 | yield(); |
8bb9da94 | 1883 | ret = kmem_cache_zalloc(journal_head_cache, GFP_NOFS); |
1da177e4 LT |
1884 | } |
1885 | } | |
1886 | return ret; | |
1887 | } | |
1888 | ||
1889 | static void journal_free_journal_head(struct journal_head *jh) | |
1890 | { | |
1891 | #ifdef CONFIG_JBD_DEBUG | |
1892 | atomic_dec(&nr_journal_heads); | |
c9cf5528 | 1893 | memset(jh, JBD_POISON_FREE, sizeof(*jh)); |
1da177e4 LT |
1894 | #endif |
1895 | kmem_cache_free(journal_head_cache, jh); | |
1896 | } | |
1897 | ||
1898 | /* | |
1899 | * A journal_head is attached to a buffer_head whenever JBD has an | |
1900 | * interest in the buffer. | |
1901 | * | |
1902 | * Whenever a buffer has an attached journal_head, its ->b_state:BH_JBD bit | |
1903 | * is set. This bit is tested in core kernel code where we need to take | |
1904 | * JBD-specific actions. Testing the zeroness of ->b_private is not reliable | |
1905 | * there. | |
1906 | * | |
1907 | * When a buffer has its BH_JBD bit set, its ->b_count is elevated by one. | |
1908 | * | |
1909 | * When a buffer has its BH_JBD bit set it is immune from being released by | |
1910 | * core kernel code, mainly via ->b_count. | |
1911 | * | |
bb189247 JK |
1912 | * A journal_head is detached from its buffer_head when the journal_head's |
1913 | * b_jcount reaches zero. Running transaction (b_transaction) and checkpoint | |
1914 | * transaction (b_cp_transaction) hold their references to b_jcount. | |
1da177e4 LT |
1915 | * |
1916 | * Various places in the kernel want to attach a journal_head to a buffer_head | |
1917 | * _before_ attaching the journal_head to a transaction. To protect the | |
1918 | * journal_head in this situation, journal_add_journal_head elevates the | |
1919 | * journal_head's b_jcount refcount by one. The caller must call | |
1920 | * journal_put_journal_head() to undo this. | |
1921 | * | |
1922 | * So the typical usage would be: | |
1923 | * | |
1924 | * (Attach a journal_head if needed. Increments b_jcount) | |
1925 | * struct journal_head *jh = journal_add_journal_head(bh); | |
1926 | * ... | |
bb189247 JK |
1927 | * (Get another reference for transaction) |
1928 | * journal_grab_journal_head(bh); | |
1929 | * jh->b_transaction = xxx; | |
1930 | * (Put original reference) | |
1931 | * journal_put_journal_head(jh); | |
1da177e4 LT |
1932 | */ |
1933 | ||
1934 | /* | |
1935 | * Give a buffer_head a journal_head. | |
1936 | * | |
1da177e4 LT |
1937 | * May sleep. |
1938 | */ | |
1939 | struct journal_head *journal_add_journal_head(struct buffer_head *bh) | |
1940 | { | |
1941 | struct journal_head *jh; | |
1942 | struct journal_head *new_jh = NULL; | |
1943 | ||
1944 | repeat: | |
8bb9da94 | 1945 | if (!buffer_jbd(bh)) |
1da177e4 | 1946 | new_jh = journal_alloc_journal_head(); |
1da177e4 LT |
1947 | |
1948 | jbd_lock_bh_journal_head(bh); | |
1949 | if (buffer_jbd(bh)) { | |
1950 | jh = bh2jh(bh); | |
1951 | } else { | |
1952 | J_ASSERT_BH(bh, | |
1953 | (atomic_read(&bh->b_count) > 0) || | |
1954 | (bh->b_page && bh->b_page->mapping)); | |
1955 | ||
1956 | if (!new_jh) { | |
1957 | jbd_unlock_bh_journal_head(bh); | |
1958 | goto repeat; | |
1959 | } | |
1960 | ||
1961 | jh = new_jh; | |
1962 | new_jh = NULL; /* We consumed it */ | |
1963 | set_buffer_jbd(bh); | |
1964 | bh->b_private = jh; | |
1965 | jh->b_bh = bh; | |
1966 | get_bh(bh); | |
1967 | BUFFER_TRACE(bh, "added journal_head"); | |
1968 | } | |
1969 | jh->b_jcount++; | |
1970 | jbd_unlock_bh_journal_head(bh); | |
1971 | if (new_jh) | |
1972 | journal_free_journal_head(new_jh); | |
1973 | return bh->b_private; | |
1974 | } | |
1975 | ||
1976 | /* | |
1977 | * Grab a ref against this buffer_head's journal_head. If it ended up not | |
1978 | * having a journal_head, return NULL | |
1979 | */ | |
1980 | struct journal_head *journal_grab_journal_head(struct buffer_head *bh) | |
1981 | { | |
1982 | struct journal_head *jh = NULL; | |
1983 | ||
1984 | jbd_lock_bh_journal_head(bh); | |
1985 | if (buffer_jbd(bh)) { | |
1986 | jh = bh2jh(bh); | |
1987 | jh->b_jcount++; | |
1988 | } | |
1989 | jbd_unlock_bh_journal_head(bh); | |
1990 | return jh; | |
1991 | } | |
1992 | ||
1993 | static void __journal_remove_journal_head(struct buffer_head *bh) | |
1994 | { | |
1995 | struct journal_head *jh = bh2jh(bh); | |
1996 | ||
1997 | J_ASSERT_JH(jh, jh->b_jcount >= 0); | |
bb189247 JK |
1998 | J_ASSERT_JH(jh, jh->b_transaction == NULL); |
1999 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); | |
2000 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); | |
2001 | J_ASSERT_JH(jh, jh->b_jlist == BJ_None); | |
2002 | J_ASSERT_BH(bh, buffer_jbd(bh)); | |
2003 | J_ASSERT_BH(bh, jh2bh(jh) == bh); | |
2004 | BUFFER_TRACE(bh, "remove journal_head"); | |
2005 | if (jh->b_frozen_data) { | |
2006 | printk(KERN_WARNING "%s: freeing b_frozen_data\n", __func__); | |
2007 | jbd_free(jh->b_frozen_data, bh->b_size); | |
1da177e4 | 2008 | } |
bb189247 JK |
2009 | if (jh->b_committed_data) { |
2010 | printk(KERN_WARNING "%s: freeing b_committed_data\n", __func__); | |
2011 | jbd_free(jh->b_committed_data, bh->b_size); | |
2012 | } | |
2013 | bh->b_private = NULL; | |
2014 | jh->b_bh = NULL; /* debug, really */ | |
2015 | clear_buffer_jbd(bh); | |
2016 | journal_free_journal_head(jh); | |
1da177e4 LT |
2017 | } |
2018 | ||
2019 | /* | |
bb189247 | 2020 | * Drop a reference on the passed journal_head. If it fell to zero then |
1da177e4 LT |
2021 | * release the journal_head from the buffer_head. |
2022 | */ | |
2023 | void journal_put_journal_head(struct journal_head *jh) | |
2024 | { | |
2025 | struct buffer_head *bh = jh2bh(jh); | |
2026 | ||
2027 | jbd_lock_bh_journal_head(bh); | |
2028 | J_ASSERT_JH(jh, jh->b_jcount > 0); | |
2029 | --jh->b_jcount; | |
bb189247 | 2030 | if (!jh->b_jcount) { |
1da177e4 | 2031 | __journal_remove_journal_head(bh); |
bb189247 | 2032 | jbd_unlock_bh_journal_head(bh); |
1da177e4 | 2033 | __brelse(bh); |
bb189247 JK |
2034 | } else |
2035 | jbd_unlock_bh_journal_head(bh); | |
1da177e4 LT |
2036 | } |
2037 | ||
2038 | /* | |
c2a9159c | 2039 | * debugfs tunables |
1da177e4 | 2040 | */ |
c2a9159c | 2041 | #ifdef CONFIG_JBD_DEBUG |
1da177e4 | 2042 | |
c2a9159c JS |
2043 | u8 journal_enable_debug __read_mostly; |
2044 | EXPORT_SYMBOL(journal_enable_debug); | |
1da177e4 | 2045 | |
c2a9159c JS |
2046 | static struct dentry *jbd_debugfs_dir; |
2047 | static struct dentry *jbd_debug; | |
1da177e4 | 2048 | |
c2a9159c | 2049 | static void __init jbd_create_debugfs_entry(void) |
1da177e4 | 2050 | { |
c2a9159c JS |
2051 | jbd_debugfs_dir = debugfs_create_dir("jbd", NULL); |
2052 | if (jbd_debugfs_dir) | |
765f8361 | 2053 | jbd_debug = debugfs_create_u8("jbd-debug", S_IRUGO | S_IWUSR, |
c2a9159c JS |
2054 | jbd_debugfs_dir, |
2055 | &journal_enable_debug); | |
1da177e4 LT |
2056 | } |
2057 | ||
c2a9159c | 2058 | static void __exit jbd_remove_debugfs_entry(void) |
1da177e4 | 2059 | { |
c2a9159c JS |
2060 | debugfs_remove(jbd_debug); |
2061 | debugfs_remove(jbd_debugfs_dir); | |
1da177e4 LT |
2062 | } |
2063 | ||
c2a9159c | 2064 | #else |
1da177e4 | 2065 | |
c2a9159c | 2066 | static inline void jbd_create_debugfs_entry(void) |
1da177e4 | 2067 | { |
1da177e4 LT |
2068 | } |
2069 | ||
c2a9159c | 2070 | static inline void jbd_remove_debugfs_entry(void) |
1da177e4 | 2071 | { |
1da177e4 LT |
2072 | } |
2073 | ||
1da177e4 LT |
2074 | #endif |
2075 | ||
e18b890b | 2076 | struct kmem_cache *jbd_handle_cache; |
1da177e4 LT |
2077 | |
2078 | static int __init journal_init_handle_cache(void) | |
2079 | { | |
2080 | jbd_handle_cache = kmem_cache_create("journal_handle", | |
2081 | sizeof(handle_t), | |
2082 | 0, /* offset */ | |
e12ba74d | 2083 | SLAB_TEMPORARY, /* flags */ |
20c2df83 | 2084 | NULL); /* ctor */ |
1da177e4 LT |
2085 | if (jbd_handle_cache == NULL) { |
2086 | printk(KERN_EMERG "JBD: failed to create handle cache\n"); | |
2087 | return -ENOMEM; | |
2088 | } | |
2089 | return 0; | |
2090 | } | |
2091 | ||
2092 | static void journal_destroy_handle_cache(void) | |
2093 | { | |
2094 | if (jbd_handle_cache) | |
2095 | kmem_cache_destroy(jbd_handle_cache); | |
2096 | } | |
2097 | ||
2098 | /* | |
2099 | * Module startup and shutdown | |
2100 | */ | |
2101 | ||
2102 | static int __init journal_init_caches(void) | |
2103 | { | |
2104 | int ret; | |
2105 | ||
2106 | ret = journal_init_revoke_caches(); | |
2107 | if (ret == 0) | |
2108 | ret = journal_init_journal_head_cache(); | |
2109 | if (ret == 0) | |
2110 | ret = journal_init_handle_cache(); | |
2111 | return ret; | |
2112 | } | |
2113 | ||
2114 | static void journal_destroy_caches(void) | |
2115 | { | |
2116 | journal_destroy_revoke_caches(); | |
2117 | journal_destroy_journal_head_cache(); | |
2118 | journal_destroy_handle_cache(); | |
2119 | } | |
2120 | ||
2121 | static int __init journal_init(void) | |
2122 | { | |
2123 | int ret; | |
2124 | ||
2aed3484 | 2125 | BUILD_BUG_ON(sizeof(struct journal_superblock_s) != 1024); |
022a4a7b | 2126 | |
1da177e4 LT |
2127 | ret = journal_init_caches(); |
2128 | if (ret != 0) | |
2129 | journal_destroy_caches(); | |
c2a9159c | 2130 | jbd_create_debugfs_entry(); |
1da177e4 LT |
2131 | return ret; |
2132 | } | |
2133 | ||
2134 | static void __exit journal_exit(void) | |
2135 | { | |
2136 | #ifdef CONFIG_JBD_DEBUG | |
2137 | int n = atomic_read(&nr_journal_heads); | |
2138 | if (n) | |
2139 | printk(KERN_EMERG "JBD: leaked %d journal_heads!\n", n); | |
2140 | #endif | |
c2a9159c | 2141 | jbd_remove_debugfs_entry(); |
1da177e4 LT |
2142 | journal_destroy_caches(); |
2143 | } | |
2144 | ||
2145 | MODULE_LICENSE("GPL"); | |
2146 | module_init(journal_init); | |
2147 | module_exit(journal_exit); | |
2148 |