Commit | Line | Data |
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470decc6 | 1 | /* |
f7f4bccb | 2 | * linux/fs/jbd2/journal.c |
470decc6 DK |
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> | |
f7f4bccb | 28 | #include <linux/jbd2.h> |
470decc6 DK |
29 | #include <linux/errno.h> |
30 | #include <linux/slab.h> | |
470decc6 DK |
31 | #include <linux/init.h> |
32 | #include <linux/mm.h> | |
7dfb7103 | 33 | #include <linux/freezer.h> |
470decc6 DK |
34 | #include <linux/pagemap.h> |
35 | #include <linux/kthread.h> | |
36 | #include <linux/poison.h> | |
37 | #include <linux/proc_fs.h> | |
0f49d5d0 | 38 | #include <linux/debugfs.h> |
8e85fb3f | 39 | #include <linux/seq_file.h> |
c225aa57 | 40 | #include <linux/math64.h> |
879c5e6b | 41 | #include <linux/hash.h> |
d2eecb03 TT |
42 | #include <linux/log2.h> |
43 | #include <linux/vmalloc.h> | |
47def826 | 44 | #include <linux/backing-dev.h> |
39e3ac25 | 45 | #include <linux/bitops.h> |
670be5a7 | 46 | #include <linux/ratelimit.h> |
879c5e6b TT |
47 | |
48 | #define CREATE_TRACE_POINTS | |
49 | #include <trace/events/jbd2.h> | |
470decc6 DK |
50 | |
51 | #include <asm/uaccess.h> | |
52 | #include <asm/page.h> | |
39e3ac25 | 53 | #include <asm/system.h> |
470decc6 | 54 | |
f7f4bccb MC |
55 | EXPORT_SYMBOL(jbd2_journal_extend); |
56 | EXPORT_SYMBOL(jbd2_journal_stop); | |
57 | EXPORT_SYMBOL(jbd2_journal_lock_updates); | |
58 | EXPORT_SYMBOL(jbd2_journal_unlock_updates); | |
59 | EXPORT_SYMBOL(jbd2_journal_get_write_access); | |
60 | EXPORT_SYMBOL(jbd2_journal_get_create_access); | |
61 | EXPORT_SYMBOL(jbd2_journal_get_undo_access); | |
e06c8227 | 62 | EXPORT_SYMBOL(jbd2_journal_set_triggers); |
f7f4bccb MC |
63 | EXPORT_SYMBOL(jbd2_journal_dirty_metadata); |
64 | EXPORT_SYMBOL(jbd2_journal_release_buffer); | |
65 | EXPORT_SYMBOL(jbd2_journal_forget); | |
470decc6 DK |
66 | #if 0 |
67 | EXPORT_SYMBOL(journal_sync_buffer); | |
68 | #endif | |
f7f4bccb MC |
69 | EXPORT_SYMBOL(jbd2_journal_flush); |
70 | EXPORT_SYMBOL(jbd2_journal_revoke); | |
71 | ||
72 | EXPORT_SYMBOL(jbd2_journal_init_dev); | |
73 | EXPORT_SYMBOL(jbd2_journal_init_inode); | |
f7f4bccb MC |
74 | EXPORT_SYMBOL(jbd2_journal_check_used_features); |
75 | EXPORT_SYMBOL(jbd2_journal_check_available_features); | |
76 | EXPORT_SYMBOL(jbd2_journal_set_features); | |
f7f4bccb MC |
77 | EXPORT_SYMBOL(jbd2_journal_load); |
78 | EXPORT_SYMBOL(jbd2_journal_destroy); | |
f7f4bccb MC |
79 | EXPORT_SYMBOL(jbd2_journal_abort); |
80 | EXPORT_SYMBOL(jbd2_journal_errno); | |
81 | EXPORT_SYMBOL(jbd2_journal_ack_err); | |
82 | EXPORT_SYMBOL(jbd2_journal_clear_err); | |
83 | EXPORT_SYMBOL(jbd2_log_wait_commit); | |
3b799d15 | 84 | EXPORT_SYMBOL(jbd2_log_start_commit); |
f7f4bccb MC |
85 | EXPORT_SYMBOL(jbd2_journal_start_commit); |
86 | EXPORT_SYMBOL(jbd2_journal_force_commit_nested); | |
87 | EXPORT_SYMBOL(jbd2_journal_wipe); | |
88 | EXPORT_SYMBOL(jbd2_journal_blocks_per_page); | |
89 | EXPORT_SYMBOL(jbd2_journal_invalidatepage); | |
90 | EXPORT_SYMBOL(jbd2_journal_try_to_free_buffers); | |
91 | EXPORT_SYMBOL(jbd2_journal_force_commit); | |
c851ed54 JK |
92 | EXPORT_SYMBOL(jbd2_journal_file_inode); |
93 | EXPORT_SYMBOL(jbd2_journal_init_jbd_inode); | |
94 | EXPORT_SYMBOL(jbd2_journal_release_jbd_inode); | |
95 | EXPORT_SYMBOL(jbd2_journal_begin_ordered_truncate); | |
8aefcd55 | 96 | EXPORT_SYMBOL(jbd2_inode_cache); |
470decc6 | 97 | |
470decc6 | 98 | static void __journal_abort_soft (journal_t *journal, int errno); |
d2eecb03 | 99 | static int jbd2_journal_create_slab(size_t slab_size); |
470decc6 DK |
100 | |
101 | /* | |
102 | * Helper function used to manage commit timeouts | |
103 | */ | |
104 | ||
105 | static void commit_timeout(unsigned long __data) | |
106 | { | |
107 | struct task_struct * p = (struct task_struct *) __data; | |
108 | ||
109 | wake_up_process(p); | |
110 | } | |
111 | ||
112 | /* | |
f7f4bccb | 113 | * kjournald2: The main thread function used to manage a logging device |
470decc6 DK |
114 | * journal. |
115 | * | |
116 | * This kernel thread is responsible for two things: | |
117 | * | |
118 | * 1) COMMIT: Every so often we need to commit the current state of the | |
119 | * filesystem to disk. The journal thread is responsible for writing | |
120 | * all of the metadata buffers to disk. | |
121 | * | |
122 | * 2) CHECKPOINT: We cannot reuse a used section of the log file until all | |
123 | * of the data in that part of the log has been rewritten elsewhere on | |
124 | * the disk. Flushing these old buffers to reclaim space in the log is | |
125 | * known as checkpointing, and this thread is responsible for that job. | |
126 | */ | |
127 | ||
f7f4bccb | 128 | static int kjournald2(void *arg) |
470decc6 DK |
129 | { |
130 | journal_t *journal = arg; | |
131 | transaction_t *transaction; | |
132 | ||
133 | /* | |
134 | * Set up an interval timer which can be used to trigger a commit wakeup | |
135 | * after the commit interval expires | |
136 | */ | |
137 | setup_timer(&journal->j_commit_timer, commit_timeout, | |
138 | (unsigned long)current); | |
139 | ||
140 | /* Record that the journal thread is running */ | |
141 | journal->j_task = current; | |
142 | wake_up(&journal->j_wait_done_commit); | |
143 | ||
470decc6 DK |
144 | /* |
145 | * And now, wait forever for commit wakeup events. | |
146 | */ | |
a931da6a | 147 | write_lock(&journal->j_state_lock); |
470decc6 DK |
148 | |
149 | loop: | |
f7f4bccb | 150 | if (journal->j_flags & JBD2_UNMOUNT) |
470decc6 DK |
151 | goto end_loop; |
152 | ||
153 | jbd_debug(1, "commit_sequence=%d, commit_request=%d\n", | |
154 | journal->j_commit_sequence, journal->j_commit_request); | |
155 | ||
156 | if (journal->j_commit_sequence != journal->j_commit_request) { | |
157 | jbd_debug(1, "OK, requests differ\n"); | |
a931da6a | 158 | write_unlock(&journal->j_state_lock); |
470decc6 | 159 | del_timer_sync(&journal->j_commit_timer); |
f7f4bccb | 160 | jbd2_journal_commit_transaction(journal); |
a931da6a | 161 | write_lock(&journal->j_state_lock); |
470decc6 DK |
162 | goto loop; |
163 | } | |
164 | ||
165 | wake_up(&journal->j_wait_done_commit); | |
166 | if (freezing(current)) { | |
167 | /* | |
168 | * The simpler the better. Flushing journal isn't a | |
169 | * good idea, because that depends on threads that may | |
170 | * be already stopped. | |
171 | */ | |
f7f4bccb | 172 | jbd_debug(1, "Now suspending kjournald2\n"); |
a931da6a | 173 | write_unlock(&journal->j_state_lock); |
a0acae0e | 174 | try_to_freeze(); |
a931da6a | 175 | write_lock(&journal->j_state_lock); |
470decc6 DK |
176 | } else { |
177 | /* | |
178 | * We assume on resume that commits are already there, | |
179 | * so we don't sleep | |
180 | */ | |
181 | DEFINE_WAIT(wait); | |
182 | int should_sleep = 1; | |
183 | ||
184 | prepare_to_wait(&journal->j_wait_commit, &wait, | |
185 | TASK_INTERRUPTIBLE); | |
186 | if (journal->j_commit_sequence != journal->j_commit_request) | |
187 | should_sleep = 0; | |
188 | transaction = journal->j_running_transaction; | |
189 | if (transaction && time_after_eq(jiffies, | |
190 | transaction->t_expires)) | |
191 | should_sleep = 0; | |
f7f4bccb | 192 | if (journal->j_flags & JBD2_UNMOUNT) |
470decc6 DK |
193 | should_sleep = 0; |
194 | if (should_sleep) { | |
a931da6a | 195 | write_unlock(&journal->j_state_lock); |
470decc6 | 196 | schedule(); |
a931da6a | 197 | write_lock(&journal->j_state_lock); |
470decc6 DK |
198 | } |
199 | finish_wait(&journal->j_wait_commit, &wait); | |
200 | } | |
201 | ||
f7f4bccb | 202 | jbd_debug(1, "kjournald2 wakes\n"); |
470decc6 DK |
203 | |
204 | /* | |
205 | * Were we woken up by a commit wakeup event? | |
206 | */ | |
207 | transaction = journal->j_running_transaction; | |
208 | if (transaction && time_after_eq(jiffies, transaction->t_expires)) { | |
209 | journal->j_commit_request = transaction->t_tid; | |
210 | jbd_debug(1, "woke because of timeout\n"); | |
211 | } | |
212 | goto loop; | |
213 | ||
214 | end_loop: | |
a931da6a | 215 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
216 | del_timer_sync(&journal->j_commit_timer); |
217 | journal->j_task = NULL; | |
218 | wake_up(&journal->j_wait_done_commit); | |
219 | jbd_debug(1, "Journal thread exiting.\n"); | |
220 | return 0; | |
221 | } | |
222 | ||
97f06784 | 223 | static int jbd2_journal_start_thread(journal_t *journal) |
470decc6 | 224 | { |
97f06784 PE |
225 | struct task_struct *t; |
226 | ||
90576c0b TT |
227 | t = kthread_run(kjournald2, journal, "jbd2/%s", |
228 | journal->j_devname); | |
97f06784 PE |
229 | if (IS_ERR(t)) |
230 | return PTR_ERR(t); | |
231 | ||
1076d17a | 232 | wait_event(journal->j_wait_done_commit, journal->j_task != NULL); |
97f06784 | 233 | return 0; |
470decc6 DK |
234 | } |
235 | ||
236 | static void journal_kill_thread(journal_t *journal) | |
237 | { | |
a931da6a | 238 | write_lock(&journal->j_state_lock); |
f7f4bccb | 239 | journal->j_flags |= JBD2_UNMOUNT; |
470decc6 DK |
240 | |
241 | while (journal->j_task) { | |
242 | wake_up(&journal->j_wait_commit); | |
a931da6a | 243 | write_unlock(&journal->j_state_lock); |
1076d17a | 244 | wait_event(journal->j_wait_done_commit, journal->j_task == NULL); |
a931da6a | 245 | write_lock(&journal->j_state_lock); |
470decc6 | 246 | } |
a931da6a | 247 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
248 | } |
249 | ||
250 | /* | |
f7f4bccb | 251 | * jbd2_journal_write_metadata_buffer: write a metadata buffer to the journal. |
470decc6 DK |
252 | * |
253 | * Writes a metadata buffer to a given disk block. The actual IO is not | |
254 | * performed but a new buffer_head is constructed which labels the data | |
255 | * to be written with the correct destination disk block. | |
256 | * | |
257 | * Any magic-number escaping which needs to be done will cause a | |
258 | * copy-out here. If the buffer happens to start with the | |
f7f4bccb | 259 | * JBD2_MAGIC_NUMBER, then we can't write it to the log directly: the |
470decc6 DK |
260 | * magic number is only written to the log for descripter blocks. In |
261 | * this case, we copy the data and replace the first word with 0, and we | |
262 | * return a result code which indicates that this buffer needs to be | |
263 | * marked as an escaped buffer in the corresponding log descriptor | |
264 | * block. The missing word can then be restored when the block is read | |
265 | * during recovery. | |
266 | * | |
267 | * If the source buffer has already been modified by a new transaction | |
268 | * since we took the last commit snapshot, we use the frozen copy of | |
269 | * that data for IO. If we end up using the existing buffer_head's data | |
270 | * for the write, then we *have* to lock the buffer to prevent anyone | |
271 | * else from using and possibly modifying it while the IO is in | |
272 | * progress. | |
273 | * | |
274 | * The function returns a pointer to the buffer_heads to be used for IO. | |
275 | * | |
276 | * We assume that the journal has already been locked in this function. | |
277 | * | |
278 | * Return value: | |
279 | * <0: Error | |
280 | * >=0: Finished OK | |
281 | * | |
282 | * On success: | |
283 | * Bit 0 set == escape performed on the data | |
284 | * Bit 1 set == buffer copy-out performed (kfree the data after IO) | |
285 | */ | |
286 | ||
f7f4bccb | 287 | int jbd2_journal_write_metadata_buffer(transaction_t *transaction, |
470decc6 DK |
288 | struct journal_head *jh_in, |
289 | struct journal_head **jh_out, | |
18eba7aa | 290 | unsigned long long blocknr) |
470decc6 DK |
291 | { |
292 | int need_copy_out = 0; | |
293 | int done_copy_out = 0; | |
294 | int do_escape = 0; | |
295 | char *mapped_data; | |
296 | struct buffer_head *new_bh; | |
297 | struct journal_head *new_jh; | |
298 | struct page *new_page; | |
299 | unsigned int new_offset; | |
300 | struct buffer_head *bh_in = jh2bh(jh_in); | |
96577c43 | 301 | journal_t *journal = transaction->t_journal; |
470decc6 DK |
302 | |
303 | /* | |
304 | * The buffer really shouldn't be locked: only the current committing | |
305 | * transaction is allowed to write it, so nobody else is allowed | |
306 | * to do any IO. | |
307 | * | |
308 | * akpm: except if we're journalling data, and write() output is | |
309 | * also part of a shared mapping, and another thread has | |
310 | * decided to launch a writepage() against this buffer. | |
311 | */ | |
312 | J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in)); | |
313 | ||
47def826 TT |
314 | retry_alloc: |
315 | new_bh = alloc_buffer_head(GFP_NOFS); | |
316 | if (!new_bh) { | |
317 | /* | |
318 | * Failure is not an option, but __GFP_NOFAIL is going | |
319 | * away; so we retry ourselves here. | |
320 | */ | |
321 | congestion_wait(BLK_RW_ASYNC, HZ/50); | |
322 | goto retry_alloc; | |
323 | } | |
324 | ||
96577c43 | 325 | /* keep subsequent assertions sane */ |
326 | new_bh->b_state = 0; | |
327 | init_buffer(new_bh, NULL, NULL); | |
328 | atomic_set(&new_bh->b_count, 1); | |
329 | new_jh = jbd2_journal_add_journal_head(new_bh); /* This sleeps */ | |
470decc6 DK |
330 | |
331 | /* | |
332 | * If a new transaction has already done a buffer copy-out, then | |
333 | * we use that version of the data for the commit. | |
334 | */ | |
335 | jbd_lock_bh_state(bh_in); | |
336 | repeat: | |
337 | if (jh_in->b_frozen_data) { | |
338 | done_copy_out = 1; | |
339 | new_page = virt_to_page(jh_in->b_frozen_data); | |
340 | new_offset = offset_in_page(jh_in->b_frozen_data); | |
341 | } else { | |
342 | new_page = jh2bh(jh_in)->b_page; | |
343 | new_offset = offset_in_page(jh2bh(jh_in)->b_data); | |
344 | } | |
345 | ||
346 | mapped_data = kmap_atomic(new_page, KM_USER0); | |
e06c8227 | 347 | /* |
13ceef09 JK |
348 | * Fire data frozen trigger if data already wasn't frozen. Do this |
349 | * before checking for escaping, as the trigger may modify the magic | |
350 | * offset. If a copy-out happens afterwards, it will have the correct | |
351 | * data in the buffer. | |
e06c8227 | 352 | */ |
13ceef09 JK |
353 | if (!done_copy_out) |
354 | jbd2_buffer_frozen_trigger(jh_in, mapped_data + new_offset, | |
355 | jh_in->b_triggers); | |
e06c8227 | 356 | |
470decc6 DK |
357 | /* |
358 | * Check for escaping | |
359 | */ | |
360 | if (*((__be32 *)(mapped_data + new_offset)) == | |
f7f4bccb | 361 | cpu_to_be32(JBD2_MAGIC_NUMBER)) { |
470decc6 DK |
362 | need_copy_out = 1; |
363 | do_escape = 1; | |
364 | } | |
365 | kunmap_atomic(mapped_data, KM_USER0); | |
366 | ||
367 | /* | |
368 | * Do we need to do a data copy? | |
369 | */ | |
370 | if (need_copy_out && !done_copy_out) { | |
371 | char *tmp; | |
372 | ||
373 | jbd_unlock_bh_state(bh_in); | |
af1e76d6 | 374 | tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS); |
e6ec116b TT |
375 | if (!tmp) { |
376 | jbd2_journal_put_journal_head(new_jh); | |
377 | return -ENOMEM; | |
378 | } | |
470decc6 DK |
379 | jbd_lock_bh_state(bh_in); |
380 | if (jh_in->b_frozen_data) { | |
af1e76d6 | 381 | jbd2_free(tmp, bh_in->b_size); |
470decc6 DK |
382 | goto repeat; |
383 | } | |
384 | ||
385 | jh_in->b_frozen_data = tmp; | |
386 | mapped_data = kmap_atomic(new_page, KM_USER0); | |
387 | memcpy(tmp, mapped_data + new_offset, jh2bh(jh_in)->b_size); | |
388 | kunmap_atomic(mapped_data, KM_USER0); | |
389 | ||
390 | new_page = virt_to_page(tmp); | |
391 | new_offset = offset_in_page(tmp); | |
392 | done_copy_out = 1; | |
e06c8227 JB |
393 | |
394 | /* | |
395 | * This isn't strictly necessary, as we're using frozen | |
396 | * data for the escaping, but it keeps consistency with | |
397 | * b_frozen_data usage. | |
398 | */ | |
399 | jh_in->b_frozen_triggers = jh_in->b_triggers; | |
470decc6 DK |
400 | } |
401 | ||
402 | /* | |
403 | * Did we need to do an escaping? Now we've done all the | |
404 | * copying, we can finally do so. | |
405 | */ | |
406 | if (do_escape) { | |
407 | mapped_data = kmap_atomic(new_page, KM_USER0); | |
408 | *((unsigned int *)(mapped_data + new_offset)) = 0; | |
409 | kunmap_atomic(mapped_data, KM_USER0); | |
410 | } | |
411 | ||
470decc6 DK |
412 | set_bh_page(new_bh, new_page, new_offset); |
413 | new_jh->b_transaction = NULL; | |
414 | new_bh->b_size = jh2bh(jh_in)->b_size; | |
415 | new_bh->b_bdev = transaction->t_journal->j_dev; | |
416 | new_bh->b_blocknr = blocknr; | |
417 | set_buffer_mapped(new_bh); | |
418 | set_buffer_dirty(new_bh); | |
419 | ||
420 | *jh_out = new_jh; | |
421 | ||
422 | /* | |
423 | * The to-be-written buffer needs to get moved to the io queue, | |
424 | * and the original buffer whose contents we are shadowing or | |
425 | * copying is moved to the transaction's shadow queue. | |
426 | */ | |
427 | JBUFFER_TRACE(jh_in, "file as BJ_Shadow"); | |
96577c43 | 428 | spin_lock(&journal->j_list_lock); |
429 | __jbd2_journal_file_buffer(jh_in, transaction, BJ_Shadow); | |
430 | spin_unlock(&journal->j_list_lock); | |
431 | jbd_unlock_bh_state(bh_in); | |
432 | ||
470decc6 | 433 | JBUFFER_TRACE(new_jh, "file as BJ_IO"); |
f7f4bccb | 434 | jbd2_journal_file_buffer(new_jh, transaction, BJ_IO); |
470decc6 DK |
435 | |
436 | return do_escape | (done_copy_out << 1); | |
437 | } | |
438 | ||
439 | /* | |
440 | * Allocation code for the journal file. Manage the space left in the | |
441 | * journal, so that we can begin checkpointing when appropriate. | |
442 | */ | |
443 | ||
444 | /* | |
f7f4bccb | 445 | * __jbd2_log_space_left: Return the number of free blocks left in the journal. |
470decc6 DK |
446 | * |
447 | * Called with the journal already locked. | |
448 | * | |
449 | * Called under j_state_lock | |
450 | */ | |
451 | ||
f7f4bccb | 452 | int __jbd2_log_space_left(journal_t *journal) |
470decc6 DK |
453 | { |
454 | int left = journal->j_free; | |
455 | ||
a931da6a | 456 | /* assert_spin_locked(&journal->j_state_lock); */ |
470decc6 DK |
457 | |
458 | /* | |
459 | * Be pessimistic here about the number of those free blocks which | |
460 | * might be required for log descriptor control blocks. | |
461 | */ | |
462 | ||
463 | #define MIN_LOG_RESERVED_BLOCKS 32 /* Allow for rounding errors */ | |
464 | ||
465 | left -= MIN_LOG_RESERVED_BLOCKS; | |
466 | ||
467 | if (left <= 0) | |
468 | return 0; | |
469 | left -= (left >> 3); | |
470 | return left; | |
471 | } | |
472 | ||
473 | /* | |
e4471831 TT |
474 | * Called with j_state_lock locked for writing. |
475 | * Returns true if a transaction commit was started. | |
470decc6 | 476 | */ |
f7f4bccb | 477 | int __jbd2_log_start_commit(journal_t *journal, tid_t target) |
470decc6 DK |
478 | { |
479 | /* | |
deeeaf13 TT |
480 | * The only transaction we can possibly wait upon is the |
481 | * currently running transaction (if it exists). Otherwise, | |
482 | * the target tid must be an old one. | |
470decc6 | 483 | */ |
deeeaf13 TT |
484 | if (journal->j_running_transaction && |
485 | journal->j_running_transaction->t_tid == target) { | |
470decc6 | 486 | /* |
bcf3d0bc | 487 | * We want a new commit: OK, mark the request and wakeup the |
470decc6 DK |
488 | * commit thread. We do _not_ do the commit ourselves. |
489 | */ | |
490 | ||
491 | journal->j_commit_request = target; | |
f2a44523 | 492 | jbd_debug(1, "JBD2: requesting commit %d/%d\n", |
470decc6 DK |
493 | journal->j_commit_request, |
494 | journal->j_commit_sequence); | |
495 | wake_up(&journal->j_wait_commit); | |
496 | return 1; | |
deeeaf13 TT |
497 | } else if (!tid_geq(journal->j_commit_request, target)) |
498 | /* This should never happen, but if it does, preserve | |
499 | the evidence before kjournald goes into a loop and | |
500 | increments j_commit_sequence beyond all recognition. */ | |
f2a44523 | 501 | WARN_ONCE(1, "JBD2: bad log_start_commit: %u %u %u %u\n", |
1be2add6 TT |
502 | journal->j_commit_request, |
503 | journal->j_commit_sequence, | |
504 | target, journal->j_running_transaction ? | |
505 | journal->j_running_transaction->t_tid : 0); | |
470decc6 DK |
506 | return 0; |
507 | } | |
508 | ||
f7f4bccb | 509 | int jbd2_log_start_commit(journal_t *journal, tid_t tid) |
470decc6 DK |
510 | { |
511 | int ret; | |
512 | ||
a931da6a | 513 | write_lock(&journal->j_state_lock); |
f7f4bccb | 514 | ret = __jbd2_log_start_commit(journal, tid); |
a931da6a | 515 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
516 | return ret; |
517 | } | |
518 | ||
519 | /* | |
520 | * Force and wait upon a commit if the calling process is not within | |
521 | * transaction. This is used for forcing out undo-protected data which contains | |
522 | * bitmaps, when the fs is running out of space. | |
523 | * | |
524 | * We can only force the running transaction if we don't have an active handle; | |
525 | * otherwise, we will deadlock. | |
526 | * | |
527 | * Returns true if a transaction was started. | |
528 | */ | |
f7f4bccb | 529 | int jbd2_journal_force_commit_nested(journal_t *journal) |
470decc6 DK |
530 | { |
531 | transaction_t *transaction = NULL; | |
532 | tid_t tid; | |
e4471831 | 533 | int need_to_start = 0; |
470decc6 | 534 | |
a931da6a | 535 | read_lock(&journal->j_state_lock); |
470decc6 DK |
536 | if (journal->j_running_transaction && !current->journal_info) { |
537 | transaction = journal->j_running_transaction; | |
e4471831 TT |
538 | if (!tid_geq(journal->j_commit_request, transaction->t_tid)) |
539 | need_to_start = 1; | |
470decc6 DK |
540 | } else if (journal->j_committing_transaction) |
541 | transaction = journal->j_committing_transaction; | |
542 | ||
543 | if (!transaction) { | |
a931da6a | 544 | read_unlock(&journal->j_state_lock); |
470decc6 DK |
545 | return 0; /* Nothing to retry */ |
546 | } | |
547 | ||
548 | tid = transaction->t_tid; | |
a931da6a | 549 | read_unlock(&journal->j_state_lock); |
e4471831 TT |
550 | if (need_to_start) |
551 | jbd2_log_start_commit(journal, tid); | |
f7f4bccb | 552 | jbd2_log_wait_commit(journal, tid); |
470decc6 DK |
553 | return 1; |
554 | } | |
555 | ||
556 | /* | |
557 | * Start a commit of the current running transaction (if any). Returns true | |
c88ccea3 JK |
558 | * if a transaction is going to be committed (or is currently already |
559 | * committing), and fills its tid in at *ptid | |
470decc6 | 560 | */ |
f7f4bccb | 561 | int jbd2_journal_start_commit(journal_t *journal, tid_t *ptid) |
470decc6 DK |
562 | { |
563 | int ret = 0; | |
564 | ||
a931da6a | 565 | write_lock(&journal->j_state_lock); |
470decc6 DK |
566 | if (journal->j_running_transaction) { |
567 | tid_t tid = journal->j_running_transaction->t_tid; | |
568 | ||
c88ccea3 JK |
569 | __jbd2_log_start_commit(journal, tid); |
570 | /* There's a running transaction and we've just made sure | |
571 | * it's commit has been scheduled. */ | |
572 | if (ptid) | |
470decc6 | 573 | *ptid = tid; |
c88ccea3 JK |
574 | ret = 1; |
575 | } else if (journal->j_committing_transaction) { | |
470decc6 DK |
576 | /* |
577 | * If ext3_write_super() recently started a commit, then we | |
578 | * have to wait for completion of that transaction | |
579 | */ | |
c88ccea3 JK |
580 | if (ptid) |
581 | *ptid = journal->j_committing_transaction->t_tid; | |
470decc6 DK |
582 | ret = 1; |
583 | } | |
a931da6a | 584 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
585 | return ret; |
586 | } | |
587 | ||
bbd2be36 JK |
588 | /* |
589 | * Return 1 if a given transaction has not yet sent barrier request | |
590 | * connected with a transaction commit. If 0 is returned, transaction | |
591 | * may or may not have sent the barrier. Used to avoid sending barrier | |
592 | * twice in common cases. | |
593 | */ | |
594 | int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid) | |
595 | { | |
596 | int ret = 0; | |
597 | transaction_t *commit_trans; | |
598 | ||
599 | if (!(journal->j_flags & JBD2_BARRIER)) | |
600 | return 0; | |
601 | read_lock(&journal->j_state_lock); | |
602 | /* Transaction already committed? */ | |
603 | if (tid_geq(journal->j_commit_sequence, tid)) | |
604 | goto out; | |
605 | commit_trans = journal->j_committing_transaction; | |
606 | if (!commit_trans || commit_trans->t_tid != tid) { | |
607 | ret = 1; | |
608 | goto out; | |
609 | } | |
610 | /* | |
611 | * Transaction is being committed and we already proceeded to | |
612 | * submitting a flush to fs partition? | |
613 | */ | |
614 | if (journal->j_fs_dev != journal->j_dev) { | |
615 | if (!commit_trans->t_need_data_flush || | |
616 | commit_trans->t_state >= T_COMMIT_DFLUSH) | |
617 | goto out; | |
618 | } else { | |
619 | if (commit_trans->t_state >= T_COMMIT_JFLUSH) | |
620 | goto out; | |
621 | } | |
622 | ret = 1; | |
623 | out: | |
624 | read_unlock(&journal->j_state_lock); | |
625 | return ret; | |
626 | } | |
627 | EXPORT_SYMBOL(jbd2_trans_will_send_data_barrier); | |
628 | ||
470decc6 DK |
629 | /* |
630 | * Wait for a specified commit to complete. | |
631 | * The caller may not hold the journal lock. | |
632 | */ | |
f7f4bccb | 633 | int jbd2_log_wait_commit(journal_t *journal, tid_t tid) |
470decc6 DK |
634 | { |
635 | int err = 0; | |
636 | ||
a931da6a | 637 | read_lock(&journal->j_state_lock); |
e23291b9 | 638 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
639 | if (!tid_geq(journal->j_commit_request, tid)) { |
640 | printk(KERN_EMERG | |
641 | "%s: error: j_commit_request=%d, tid=%d\n", | |
329d291f | 642 | __func__, journal->j_commit_request, tid); |
470decc6 | 643 | } |
470decc6 | 644 | #endif |
470decc6 | 645 | while (tid_gt(tid, journal->j_commit_sequence)) { |
f2a44523 | 646 | jbd_debug(1, "JBD2: want %d, j_commit_sequence=%d\n", |
470decc6 DK |
647 | tid, journal->j_commit_sequence); |
648 | wake_up(&journal->j_wait_commit); | |
a931da6a | 649 | read_unlock(&journal->j_state_lock); |
470decc6 DK |
650 | wait_event(journal->j_wait_done_commit, |
651 | !tid_gt(tid, journal->j_commit_sequence)); | |
a931da6a | 652 | read_lock(&journal->j_state_lock); |
470decc6 | 653 | } |
a931da6a | 654 | read_unlock(&journal->j_state_lock); |
470decc6 DK |
655 | |
656 | if (unlikely(is_journal_aborted(journal))) { | |
657 | printk(KERN_EMERG "journal commit I/O error\n"); | |
658 | err = -EIO; | |
659 | } | |
660 | return err; | |
661 | } | |
662 | ||
663 | /* | |
664 | * Log buffer allocation routines: | |
665 | */ | |
666 | ||
18eba7aa | 667 | int jbd2_journal_next_log_block(journal_t *journal, unsigned long long *retp) |
470decc6 DK |
668 | { |
669 | unsigned long blocknr; | |
670 | ||
a931da6a | 671 | write_lock(&journal->j_state_lock); |
470decc6 DK |
672 | J_ASSERT(journal->j_free > 1); |
673 | ||
674 | blocknr = journal->j_head; | |
675 | journal->j_head++; | |
676 | journal->j_free--; | |
677 | if (journal->j_head == journal->j_last) | |
678 | journal->j_head = journal->j_first; | |
a931da6a | 679 | write_unlock(&journal->j_state_lock); |
f7f4bccb | 680 | return jbd2_journal_bmap(journal, blocknr, retp); |
470decc6 DK |
681 | } |
682 | ||
683 | /* | |
684 | * Conversion of logical to physical block numbers for the journal | |
685 | * | |
686 | * On external journals the journal blocks are identity-mapped, so | |
687 | * this is a no-op. If needed, we can use j_blk_offset - everything is | |
688 | * ready. | |
689 | */ | |
f7f4bccb | 690 | int jbd2_journal_bmap(journal_t *journal, unsigned long blocknr, |
18eba7aa | 691 | unsigned long long *retp) |
470decc6 DK |
692 | { |
693 | int err = 0; | |
18eba7aa | 694 | unsigned long long ret; |
470decc6 DK |
695 | |
696 | if (journal->j_inode) { | |
697 | ret = bmap(journal->j_inode, blocknr); | |
698 | if (ret) | |
699 | *retp = ret; | |
700 | else { | |
470decc6 DK |
701 | printk(KERN_ALERT "%s: journal block not found " |
702 | "at offset %lu on %s\n", | |
05496769 | 703 | __func__, blocknr, journal->j_devname); |
470decc6 DK |
704 | err = -EIO; |
705 | __journal_abort_soft(journal, err); | |
706 | } | |
707 | } else { | |
708 | *retp = blocknr; /* +journal->j_blk_offset */ | |
709 | } | |
710 | return err; | |
711 | } | |
712 | ||
713 | /* | |
714 | * We play buffer_head aliasing tricks to write data/metadata blocks to | |
715 | * the journal without copying their contents, but for journal | |
716 | * descriptor blocks we do need to generate bona fide buffers. | |
717 | * | |
f7f4bccb | 718 | * After the caller of jbd2_journal_get_descriptor_buffer() has finished modifying |
470decc6 DK |
719 | * the buffer's contents they really should run flush_dcache_page(bh->b_page). |
720 | * But we don't bother doing that, so there will be coherency problems with | |
721 | * mmaps of blockdevs which hold live JBD-controlled filesystems. | |
722 | */ | |
f7f4bccb | 723 | struct journal_head *jbd2_journal_get_descriptor_buffer(journal_t *journal) |
470decc6 DK |
724 | { |
725 | struct buffer_head *bh; | |
18eba7aa | 726 | unsigned long long blocknr; |
470decc6 DK |
727 | int err; |
728 | ||
f7f4bccb | 729 | err = jbd2_journal_next_log_block(journal, &blocknr); |
470decc6 DK |
730 | |
731 | if (err) | |
732 | return NULL; | |
733 | ||
734 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
4b905671 JK |
735 | if (!bh) |
736 | return NULL; | |
470decc6 DK |
737 | lock_buffer(bh); |
738 | memset(bh->b_data, 0, journal->j_blocksize); | |
739 | set_buffer_uptodate(bh); | |
740 | unlock_buffer(bh); | |
741 | BUFFER_TRACE(bh, "return this buffer"); | |
f7f4bccb | 742 | return jbd2_journal_add_journal_head(bh); |
470decc6 DK |
743 | } |
744 | ||
79feb521 JK |
745 | /* |
746 | * Return tid of the oldest transaction in the journal and block in the journal | |
747 | * where the transaction starts. | |
748 | * | |
749 | * If the journal is now empty, return which will be the next transaction ID | |
750 | * we will write and where will that transaction start. | |
751 | * | |
752 | * The return value is 0 if journal tail cannot be pushed any further, 1 if | |
753 | * it can. | |
754 | */ | |
755 | int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, | |
756 | unsigned long *block) | |
757 | { | |
758 | transaction_t *transaction; | |
759 | int ret; | |
760 | ||
761 | read_lock(&journal->j_state_lock); | |
762 | spin_lock(&journal->j_list_lock); | |
763 | transaction = journal->j_checkpoint_transactions; | |
764 | if (transaction) { | |
765 | *tid = transaction->t_tid; | |
766 | *block = transaction->t_log_start; | |
767 | } else if ((transaction = journal->j_committing_transaction) != NULL) { | |
768 | *tid = transaction->t_tid; | |
769 | *block = transaction->t_log_start; | |
770 | } else if ((transaction = journal->j_running_transaction) != NULL) { | |
771 | *tid = transaction->t_tid; | |
772 | *block = journal->j_head; | |
773 | } else { | |
774 | *tid = journal->j_transaction_sequence; | |
775 | *block = journal->j_head; | |
776 | } | |
777 | ret = tid_gt(*tid, journal->j_tail_sequence); | |
778 | spin_unlock(&journal->j_list_lock); | |
779 | read_unlock(&journal->j_state_lock); | |
780 | ||
781 | return ret; | |
782 | } | |
783 | ||
784 | /* | |
785 | * Update information in journal structure and in on disk journal superblock | |
786 | * about log tail. This function does not check whether information passed in | |
787 | * really pushes log tail further. It's responsibility of the caller to make | |
788 | * sure provided log tail information is valid (e.g. by holding | |
789 | * j_checkpoint_mutex all the time between computing log tail and calling this | |
790 | * function as is the case with jbd2_cleanup_journal_tail()). | |
791 | * | |
792 | * Requires j_checkpoint_mutex | |
793 | */ | |
794 | void __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block) | |
795 | { | |
796 | unsigned long freed; | |
797 | ||
798 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); | |
799 | ||
800 | /* | |
801 | * We cannot afford for write to remain in drive's caches since as | |
802 | * soon as we update j_tail, next transaction can start reusing journal | |
803 | * space and if we lose sb update during power failure we'd replay | |
804 | * old transaction with possibly newly overwritten data. | |
805 | */ | |
806 | jbd2_journal_update_sb_log_tail(journal, tid, block, WRITE_FUA); | |
807 | write_lock(&journal->j_state_lock); | |
808 | freed = block - journal->j_tail; | |
809 | if (block < journal->j_tail) | |
810 | freed += journal->j_last - journal->j_first; | |
811 | ||
812 | trace_jbd2_update_log_tail(journal, tid, block, freed); | |
813 | jbd_debug(1, | |
814 | "Cleaning journal tail from %d to %d (offset %lu), " | |
815 | "freeing %lu\n", | |
816 | journal->j_tail_sequence, tid, block, freed); | |
817 | ||
818 | journal->j_free += freed; | |
819 | journal->j_tail_sequence = tid; | |
820 | journal->j_tail = block; | |
821 | write_unlock(&journal->j_state_lock); | |
822 | } | |
823 | ||
8e85fb3f JL |
824 | struct jbd2_stats_proc_session { |
825 | journal_t *journal; | |
826 | struct transaction_stats_s *stats; | |
827 | int start; | |
828 | int max; | |
829 | }; | |
830 | ||
8e85fb3f JL |
831 | static void *jbd2_seq_info_start(struct seq_file *seq, loff_t *pos) |
832 | { | |
833 | return *pos ? NULL : SEQ_START_TOKEN; | |
834 | } | |
835 | ||
836 | static void *jbd2_seq_info_next(struct seq_file *seq, void *v, loff_t *pos) | |
837 | { | |
838 | return NULL; | |
839 | } | |
840 | ||
841 | static int jbd2_seq_info_show(struct seq_file *seq, void *v) | |
842 | { | |
843 | struct jbd2_stats_proc_session *s = seq->private; | |
844 | ||
845 | if (v != SEQ_START_TOKEN) | |
846 | return 0; | |
bf699327 | 847 | seq_printf(seq, "%lu transaction, each up to %u blocks\n", |
8e85fb3f JL |
848 | s->stats->ts_tid, |
849 | s->journal->j_max_transaction_buffers); | |
850 | if (s->stats->ts_tid == 0) | |
851 | return 0; | |
852 | seq_printf(seq, "average: \n %ums waiting for transaction\n", | |
bf699327 | 853 | jiffies_to_msecs(s->stats->run.rs_wait / s->stats->ts_tid)); |
8e85fb3f | 854 | seq_printf(seq, " %ums running transaction\n", |
bf699327 | 855 | jiffies_to_msecs(s->stats->run.rs_running / s->stats->ts_tid)); |
8e85fb3f | 856 | seq_printf(seq, " %ums transaction was being locked\n", |
bf699327 | 857 | jiffies_to_msecs(s->stats->run.rs_locked / s->stats->ts_tid)); |
8e85fb3f | 858 | seq_printf(seq, " %ums flushing data (in ordered mode)\n", |
bf699327 | 859 | jiffies_to_msecs(s->stats->run.rs_flushing / s->stats->ts_tid)); |
8e85fb3f | 860 | seq_printf(seq, " %ums logging transaction\n", |
bf699327 | 861 | jiffies_to_msecs(s->stats->run.rs_logging / s->stats->ts_tid)); |
c225aa57 SHT |
862 | seq_printf(seq, " %lluus average transaction commit time\n", |
863 | div_u64(s->journal->j_average_commit_time, 1000)); | |
8e85fb3f | 864 | seq_printf(seq, " %lu handles per transaction\n", |
bf699327 | 865 | s->stats->run.rs_handle_count / s->stats->ts_tid); |
8e85fb3f | 866 | seq_printf(seq, " %lu blocks per transaction\n", |
bf699327 | 867 | s->stats->run.rs_blocks / s->stats->ts_tid); |
8e85fb3f | 868 | seq_printf(seq, " %lu logged blocks per transaction\n", |
bf699327 | 869 | s->stats->run.rs_blocks_logged / s->stats->ts_tid); |
8e85fb3f JL |
870 | return 0; |
871 | } | |
872 | ||
873 | static void jbd2_seq_info_stop(struct seq_file *seq, void *v) | |
874 | { | |
875 | } | |
876 | ||
88e9d34c | 877 | static const struct seq_operations jbd2_seq_info_ops = { |
8e85fb3f JL |
878 | .start = jbd2_seq_info_start, |
879 | .next = jbd2_seq_info_next, | |
880 | .stop = jbd2_seq_info_stop, | |
881 | .show = jbd2_seq_info_show, | |
882 | }; | |
883 | ||
884 | static int jbd2_seq_info_open(struct inode *inode, struct file *file) | |
885 | { | |
886 | journal_t *journal = PDE(inode)->data; | |
887 | struct jbd2_stats_proc_session *s; | |
888 | int rc, size; | |
889 | ||
890 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
891 | if (s == NULL) | |
892 | return -ENOMEM; | |
893 | size = sizeof(struct transaction_stats_s); | |
894 | s->stats = kmalloc(size, GFP_KERNEL); | |
895 | if (s->stats == NULL) { | |
896 | kfree(s); | |
897 | return -ENOMEM; | |
898 | } | |
899 | spin_lock(&journal->j_history_lock); | |
900 | memcpy(s->stats, &journal->j_stats, size); | |
901 | s->journal = journal; | |
902 | spin_unlock(&journal->j_history_lock); | |
903 | ||
904 | rc = seq_open(file, &jbd2_seq_info_ops); | |
905 | if (rc == 0) { | |
906 | struct seq_file *m = file->private_data; | |
907 | m->private = s; | |
908 | } else { | |
909 | kfree(s->stats); | |
910 | kfree(s); | |
911 | } | |
912 | return rc; | |
913 | ||
914 | } | |
915 | ||
916 | static int jbd2_seq_info_release(struct inode *inode, struct file *file) | |
917 | { | |
918 | struct seq_file *seq = file->private_data; | |
919 | struct jbd2_stats_proc_session *s = seq->private; | |
920 | kfree(s->stats); | |
921 | kfree(s); | |
922 | return seq_release(inode, file); | |
923 | } | |
924 | ||
828c0950 | 925 | static const struct file_operations jbd2_seq_info_fops = { |
8e85fb3f JL |
926 | .owner = THIS_MODULE, |
927 | .open = jbd2_seq_info_open, | |
928 | .read = seq_read, | |
929 | .llseek = seq_lseek, | |
930 | .release = jbd2_seq_info_release, | |
931 | }; | |
932 | ||
933 | static struct proc_dir_entry *proc_jbd2_stats; | |
934 | ||
935 | static void jbd2_stats_proc_init(journal_t *journal) | |
936 | { | |
05496769 | 937 | journal->j_proc_entry = proc_mkdir(journal->j_devname, proc_jbd2_stats); |
8e85fb3f | 938 | if (journal->j_proc_entry) { |
79da3664 DL |
939 | proc_create_data("info", S_IRUGO, journal->j_proc_entry, |
940 | &jbd2_seq_info_fops, journal); | |
8e85fb3f JL |
941 | } |
942 | } | |
943 | ||
944 | static void jbd2_stats_proc_exit(journal_t *journal) | |
945 | { | |
8e85fb3f | 946 | remove_proc_entry("info", journal->j_proc_entry); |
05496769 | 947 | remove_proc_entry(journal->j_devname, proc_jbd2_stats); |
8e85fb3f JL |
948 | } |
949 | ||
470decc6 DK |
950 | /* |
951 | * Management for journal control blocks: functions to create and | |
952 | * destroy journal_t structures, and to initialise and read existing | |
953 | * journal blocks from disk. */ | |
954 | ||
955 | /* First: create and setup a journal_t object in memory. We initialise | |
956 | * very few fields yet: that has to wait until we have created the | |
957 | * journal structures from from scratch, or loaded them from disk. */ | |
958 | ||
959 | static journal_t * journal_init_common (void) | |
960 | { | |
961 | journal_t *journal; | |
962 | int err; | |
963 | ||
3ebfdf88 | 964 | journal = kzalloc(sizeof(*journal), GFP_KERNEL); |
470decc6 | 965 | if (!journal) |
b7271b0a | 966 | return NULL; |
470decc6 DK |
967 | |
968 | init_waitqueue_head(&journal->j_wait_transaction_locked); | |
969 | init_waitqueue_head(&journal->j_wait_logspace); | |
970 | init_waitqueue_head(&journal->j_wait_done_commit); | |
971 | init_waitqueue_head(&journal->j_wait_checkpoint); | |
972 | init_waitqueue_head(&journal->j_wait_commit); | |
973 | init_waitqueue_head(&journal->j_wait_updates); | |
974 | mutex_init(&journal->j_barrier); | |
975 | mutex_init(&journal->j_checkpoint_mutex); | |
976 | spin_lock_init(&journal->j_revoke_lock); | |
977 | spin_lock_init(&journal->j_list_lock); | |
a931da6a | 978 | rwlock_init(&journal->j_state_lock); |
470decc6 | 979 | |
cd02ff0b | 980 | journal->j_commit_interval = (HZ * JBD2_DEFAULT_MAX_COMMIT_AGE); |
30773840 TT |
981 | journal->j_min_batch_time = 0; |
982 | journal->j_max_batch_time = 15000; /* 15ms */ | |
470decc6 DK |
983 | |
984 | /* The journal is marked for error until we succeed with recovery! */ | |
f7f4bccb | 985 | journal->j_flags = JBD2_ABORT; |
470decc6 DK |
986 | |
987 | /* Set up a default-sized revoke table for the new mount. */ | |
f7f4bccb | 988 | err = jbd2_journal_init_revoke(journal, JOURNAL_REVOKE_DEFAULT_HASH); |
470decc6 DK |
989 | if (err) { |
990 | kfree(journal); | |
b7271b0a | 991 | return NULL; |
470decc6 | 992 | } |
8e85fb3f | 993 | |
bf699327 | 994 | spin_lock_init(&journal->j_history_lock); |
8e85fb3f | 995 | |
470decc6 | 996 | return journal; |
470decc6 DK |
997 | } |
998 | ||
f7f4bccb | 999 | /* jbd2_journal_init_dev and jbd2_journal_init_inode: |
470decc6 DK |
1000 | * |
1001 | * Create a journal structure assigned some fixed set of disk blocks to | |
1002 | * the journal. We don't actually touch those disk blocks yet, but we | |
1003 | * need to set up all of the mapping information to tell the journaling | |
1004 | * system where the journal blocks are. | |
1005 | * | |
1006 | */ | |
1007 | ||
1008 | /** | |
5648ba5b | 1009 | * journal_t * jbd2_journal_init_dev() - creates and initialises a journal structure |
470decc6 DK |
1010 | * @bdev: Block device on which to create the journal |
1011 | * @fs_dev: Device which hold journalled filesystem for this journal. | |
1012 | * @start: Block nr Start of journal. | |
1013 | * @len: Length of the journal in blocks. | |
1014 | * @blocksize: blocksize of journalling device | |
5648ba5b RD |
1015 | * |
1016 | * Returns: a newly created journal_t * | |
470decc6 | 1017 | * |
f7f4bccb | 1018 | * jbd2_journal_init_dev creates a journal which maps a fixed contiguous |
470decc6 DK |
1019 | * range of blocks on an arbitrary block device. |
1020 | * | |
1021 | */ | |
f7f4bccb | 1022 | journal_t * jbd2_journal_init_dev(struct block_device *bdev, |
470decc6 | 1023 | struct block_device *fs_dev, |
18eba7aa | 1024 | unsigned long long start, int len, int blocksize) |
470decc6 DK |
1025 | { |
1026 | journal_t *journal = journal_init_common(); | |
1027 | struct buffer_head *bh; | |
05496769 | 1028 | char *p; |
470decc6 DK |
1029 | int n; |
1030 | ||
1031 | if (!journal) | |
1032 | return NULL; | |
1033 | ||
1034 | /* journal descriptor can store up to n blocks -bzzz */ | |
1035 | journal->j_blocksize = blocksize; | |
0587aa3d | 1036 | journal->j_dev = bdev; |
1037 | journal->j_fs_dev = fs_dev; | |
1038 | journal->j_blk_offset = start; | |
1039 | journal->j_maxlen = len; | |
1040 | bdevname(journal->j_dev, journal->j_devname); | |
1041 | p = journal->j_devname; | |
1042 | while ((p = strchr(p, '/'))) | |
1043 | *p = '!'; | |
4b905671 | 1044 | jbd2_stats_proc_init(journal); |
470decc6 DK |
1045 | n = journal->j_blocksize / sizeof(journal_block_tag_t); |
1046 | journal->j_wbufsize = n; | |
1047 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
1048 | if (!journal->j_wbuf) { | |
25985edc | 1049 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
329d291f | 1050 | __func__); |
4b905671 | 1051 | goto out_err; |
470decc6 | 1052 | } |
470decc6 DK |
1053 | |
1054 | bh = __getblk(journal->j_dev, start, journal->j_blocksize); | |
4b905671 JK |
1055 | if (!bh) { |
1056 | printk(KERN_ERR | |
1057 | "%s: Cannot get buffer for journal superblock\n", | |
1058 | __func__); | |
1059 | goto out_err; | |
1060 | } | |
470decc6 DK |
1061 | journal->j_sb_buffer = bh; |
1062 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
4b905671 | 1063 | |
470decc6 | 1064 | return journal; |
4b905671 | 1065 | out_err: |
7b02bec0 | 1066 | kfree(journal->j_wbuf); |
4b905671 JK |
1067 | jbd2_stats_proc_exit(journal); |
1068 | kfree(journal); | |
1069 | return NULL; | |
470decc6 DK |
1070 | } |
1071 | ||
1072 | /** | |
f7f4bccb | 1073 | * journal_t * jbd2_journal_init_inode () - creates a journal which maps to a inode. |
470decc6 DK |
1074 | * @inode: An inode to create the journal in |
1075 | * | |
f7f4bccb | 1076 | * jbd2_journal_init_inode creates a journal which maps an on-disk inode as |
470decc6 DK |
1077 | * the journal. The inode must exist already, must support bmap() and |
1078 | * must have all data blocks preallocated. | |
1079 | */ | |
f7f4bccb | 1080 | journal_t * jbd2_journal_init_inode (struct inode *inode) |
470decc6 DK |
1081 | { |
1082 | struct buffer_head *bh; | |
1083 | journal_t *journal = journal_init_common(); | |
05496769 | 1084 | char *p; |
470decc6 DK |
1085 | int err; |
1086 | int n; | |
18eba7aa | 1087 | unsigned long long blocknr; |
470decc6 DK |
1088 | |
1089 | if (!journal) | |
1090 | return NULL; | |
1091 | ||
1092 | journal->j_dev = journal->j_fs_dev = inode->i_sb->s_bdev; | |
1093 | journal->j_inode = inode; | |
05496769 TT |
1094 | bdevname(journal->j_dev, journal->j_devname); |
1095 | p = journal->j_devname; | |
1096 | while ((p = strchr(p, '/'))) | |
1097 | *p = '!'; | |
1098 | p = journal->j_devname + strlen(journal->j_devname); | |
90576c0b | 1099 | sprintf(p, "-%lu", journal->j_inode->i_ino); |
470decc6 DK |
1100 | jbd_debug(1, |
1101 | "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n", | |
1102 | journal, inode->i_sb->s_id, inode->i_ino, | |
1103 | (long long) inode->i_size, | |
1104 | inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize); | |
1105 | ||
1106 | journal->j_maxlen = inode->i_size >> inode->i_sb->s_blocksize_bits; | |
1107 | journal->j_blocksize = inode->i_sb->s_blocksize; | |
8e85fb3f | 1108 | jbd2_stats_proc_init(journal); |
470decc6 DK |
1109 | |
1110 | /* journal descriptor can store up to n blocks -bzzz */ | |
1111 | n = journal->j_blocksize / sizeof(journal_block_tag_t); | |
1112 | journal->j_wbufsize = n; | |
1113 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
1114 | if (!journal->j_wbuf) { | |
25985edc | 1115 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
329d291f | 1116 | __func__); |
4b905671 | 1117 | goto out_err; |
470decc6 DK |
1118 | } |
1119 | ||
f7f4bccb | 1120 | err = jbd2_journal_bmap(journal, 0, &blocknr); |
470decc6 DK |
1121 | /* If that failed, give up */ |
1122 | if (err) { | |
3c26bdb4 | 1123 | printk(KERN_ERR "%s: Cannot locate journal superblock\n", |
329d291f | 1124 | __func__); |
4b905671 | 1125 | goto out_err; |
470decc6 DK |
1126 | } |
1127 | ||
1128 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
4b905671 JK |
1129 | if (!bh) { |
1130 | printk(KERN_ERR | |
1131 | "%s: Cannot get buffer for journal superblock\n", | |
1132 | __func__); | |
1133 | goto out_err; | |
1134 | } | |
470decc6 DK |
1135 | journal->j_sb_buffer = bh; |
1136 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
1137 | ||
1138 | return journal; | |
4b905671 | 1139 | out_err: |
7b02bec0 | 1140 | kfree(journal->j_wbuf); |
4b905671 JK |
1141 | jbd2_stats_proc_exit(journal); |
1142 | kfree(journal); | |
1143 | return NULL; | |
470decc6 DK |
1144 | } |
1145 | ||
1146 | /* | |
1147 | * If the journal init or create aborts, we need to mark the journal | |
1148 | * superblock as being NULL to prevent the journal destroy from writing | |
1149 | * back a bogus superblock. | |
1150 | */ | |
1151 | static void journal_fail_superblock (journal_t *journal) | |
1152 | { | |
1153 | struct buffer_head *bh = journal->j_sb_buffer; | |
1154 | brelse(bh); | |
1155 | journal->j_sb_buffer = NULL; | |
1156 | } | |
1157 | ||
1158 | /* | |
1159 | * Given a journal_t structure, initialise the various fields for | |
1160 | * startup of a new journaling session. We use this both when creating | |
1161 | * a journal, and after recovering an old journal to reset it for | |
1162 | * subsequent use. | |
1163 | */ | |
1164 | ||
1165 | static int journal_reset(journal_t *journal) | |
1166 | { | |
1167 | journal_superblock_t *sb = journal->j_superblock; | |
18eba7aa | 1168 | unsigned long long first, last; |
470decc6 DK |
1169 | |
1170 | first = be32_to_cpu(sb->s_first); | |
1171 | last = be32_to_cpu(sb->s_maxlen); | |
f6f50e28 | 1172 | if (first + JBD2_MIN_JOURNAL_BLOCKS > last + 1) { |
f2a44523 | 1173 | printk(KERN_ERR "JBD2: Journal too short (blocks %llu-%llu).\n", |
f6f50e28 JK |
1174 | first, last); |
1175 | journal_fail_superblock(journal); | |
1176 | return -EINVAL; | |
1177 | } | |
470decc6 DK |
1178 | |
1179 | journal->j_first = first; | |
1180 | journal->j_last = last; | |
1181 | ||
1182 | journal->j_head = first; | |
1183 | journal->j_tail = first; | |
1184 | journal->j_free = last - first; | |
1185 | ||
1186 | journal->j_tail_sequence = journal->j_transaction_sequence; | |
1187 | journal->j_commit_sequence = journal->j_transaction_sequence - 1; | |
1188 | journal->j_commit_request = journal->j_commit_sequence; | |
1189 | ||
1190 | journal->j_max_transaction_buffers = journal->j_maxlen / 4; | |
1191 | ||
470decc6 DK |
1192 | /* |
1193 | * As a special case, if the on-disk copy is already marked as needing | |
24bcc89c JK |
1194 | * no recovery (s_start == 0), then we can safely defer the superblock |
1195 | * update until the next commit by setting JBD2_FLUSHED. This avoids | |
470decc6 DK |
1196 | * attempting a write to a potential-readonly device. |
1197 | */ | |
24bcc89c | 1198 | if (sb->s_start == 0) { |
f2a44523 | 1199 | jbd_debug(1, "JBD2: Skipping superblock update on recovered sb " |
470decc6 DK |
1200 | "(start %ld, seq %d, errno %d)\n", |
1201 | journal->j_tail, journal->j_tail_sequence, | |
1202 | journal->j_errno); | |
24bcc89c JK |
1203 | journal->j_flags |= JBD2_FLUSHED; |
1204 | } else { | |
a78bb11d JK |
1205 | /* Lock here to make assertions happy... */ |
1206 | mutex_lock(&journal->j_checkpoint_mutex); | |
79feb521 JK |
1207 | /* |
1208 | * Update log tail information. We use WRITE_FUA since new | |
1209 | * transaction will start reusing journal space and so we | |
1210 | * must make sure information about current log tail is on | |
1211 | * disk before that. | |
1212 | */ | |
1213 | jbd2_journal_update_sb_log_tail(journal, | |
1214 | journal->j_tail_sequence, | |
1215 | journal->j_tail, | |
1216 | WRITE_FUA); | |
a78bb11d | 1217 | mutex_unlock(&journal->j_checkpoint_mutex); |
470decc6 | 1218 | } |
24bcc89c JK |
1219 | return jbd2_journal_start_thread(journal); |
1220 | } | |
1221 | ||
79feb521 | 1222 | static void jbd2_write_superblock(journal_t *journal, int write_op) |
24bcc89c JK |
1223 | { |
1224 | struct buffer_head *bh = journal->j_sb_buffer; | |
79feb521 | 1225 | int ret; |
470decc6 | 1226 | |
79feb521 JK |
1227 | trace_jbd2_write_superblock(journal, write_op); |
1228 | if (!(journal->j_flags & JBD2_BARRIER)) | |
1229 | write_op &= ~(REQ_FUA | REQ_FLUSH); | |
1230 | lock_buffer(bh); | |
914258bf TT |
1231 | if (buffer_write_io_error(bh)) { |
1232 | /* | |
1233 | * Oh, dear. A previous attempt to write the journal | |
1234 | * superblock failed. This could happen because the | |
1235 | * USB device was yanked out. Or it could happen to | |
1236 | * be a transient write error and maybe the block will | |
1237 | * be remapped. Nothing we can do but to retry the | |
1238 | * write and hope for the best. | |
1239 | */ | |
1240 | printk(KERN_ERR "JBD2: previous I/O error detected " | |
1241 | "for journal superblock update for %s.\n", | |
1242 | journal->j_devname); | |
1243 | clear_buffer_write_io_error(bh); | |
1244 | set_buffer_uptodate(bh); | |
1245 | } | |
79feb521 JK |
1246 | get_bh(bh); |
1247 | bh->b_end_io = end_buffer_write_sync; | |
1248 | ret = submit_bh(write_op, bh); | |
1249 | wait_on_buffer(bh); | |
24bcc89c | 1250 | if (buffer_write_io_error(bh)) { |
24bcc89c JK |
1251 | clear_buffer_write_io_error(bh); |
1252 | set_buffer_uptodate(bh); | |
79feb521 JK |
1253 | ret = -EIO; |
1254 | } | |
1255 | if (ret) { | |
1256 | printk(KERN_ERR "JBD2: Error %d detected when updating " | |
1257 | "journal superblock for %s.\n", ret, | |
1258 | journal->j_devname); | |
24bcc89c JK |
1259 | } |
1260 | } | |
1261 | ||
1262 | /** | |
1263 | * jbd2_journal_update_sb_log_tail() - Update log tail in journal sb on disk. | |
1264 | * @journal: The journal to update. | |
79feb521 JK |
1265 | * @tail_tid: TID of the new transaction at the tail of the log |
1266 | * @tail_block: The first block of the transaction at the tail of the log | |
1267 | * @write_op: With which operation should we write the journal sb | |
24bcc89c JK |
1268 | * |
1269 | * Update a journal's superblock information about log tail and write it to | |
1270 | * disk, waiting for the IO to complete. | |
1271 | */ | |
79feb521 JK |
1272 | void jbd2_journal_update_sb_log_tail(journal_t *journal, tid_t tail_tid, |
1273 | unsigned long tail_block, int write_op) | |
24bcc89c JK |
1274 | { |
1275 | journal_superblock_t *sb = journal->j_superblock; | |
1276 | ||
a78bb11d | 1277 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); |
79feb521 JK |
1278 | jbd_debug(1, "JBD2: updating superblock (start %lu, seq %u)\n", |
1279 | tail_block, tail_tid); | |
470decc6 | 1280 | |
79feb521 JK |
1281 | sb->s_sequence = cpu_to_be32(tail_tid); |
1282 | sb->s_start = cpu_to_be32(tail_block); | |
470decc6 | 1283 | |
79feb521 | 1284 | jbd2_write_superblock(journal, write_op); |
470decc6 | 1285 | |
24bcc89c JK |
1286 | /* Log is no longer empty */ |
1287 | write_lock(&journal->j_state_lock); | |
1288 | WARN_ON(!sb->s_sequence); | |
1289 | journal->j_flags &= ~JBD2_FLUSHED; | |
1290 | write_unlock(&journal->j_state_lock); | |
1291 | } | |
2201c590 | 1292 | |
24bcc89c JK |
1293 | /** |
1294 | * jbd2_mark_journal_empty() - Mark on disk journal as empty. | |
1295 | * @journal: The journal to update. | |
1296 | * | |
1297 | * Update a journal's dynamic superblock fields to show that journal is empty. | |
1298 | * Write updated superblock to disk waiting for IO to complete. | |
1299 | */ | |
1300 | static void jbd2_mark_journal_empty(journal_t *journal) | |
1301 | { | |
1302 | journal_superblock_t *sb = journal->j_superblock; | |
1303 | ||
a78bb11d | 1304 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); |
24bcc89c JK |
1305 | read_lock(&journal->j_state_lock); |
1306 | jbd_debug(1, "JBD2: Marking journal as empty (seq %d)\n", | |
1307 | journal->j_tail_sequence); | |
470decc6 | 1308 | |
24bcc89c JK |
1309 | sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); |
1310 | sb->s_start = cpu_to_be32(0); | |
1311 | read_unlock(&journal->j_state_lock); | |
1312 | ||
79feb521 | 1313 | jbd2_write_superblock(journal, WRITE_FUA); |
24bcc89c JK |
1314 | |
1315 | /* Log is no longer empty */ | |
a931da6a | 1316 | write_lock(&journal->j_state_lock); |
24bcc89c | 1317 | journal->j_flags |= JBD2_FLUSHED; |
a931da6a | 1318 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1319 | } |
1320 | ||
24bcc89c JK |
1321 | |
1322 | /** | |
1323 | * jbd2_journal_update_sb_errno() - Update error in the journal. | |
1324 | * @journal: The journal to update. | |
1325 | * | |
1326 | * Update a journal's errno. Write updated superblock to disk waiting for IO | |
1327 | * to complete. | |
1328 | */ | |
1329 | static void jbd2_journal_update_sb_errno(journal_t *journal) | |
1330 | { | |
1331 | journal_superblock_t *sb = journal->j_superblock; | |
1332 | ||
1333 | read_lock(&journal->j_state_lock); | |
1334 | jbd_debug(1, "JBD2: updating superblock error (errno %d)\n", | |
1335 | journal->j_errno); | |
1336 | sb->s_errno = cpu_to_be32(journal->j_errno); | |
1337 | read_unlock(&journal->j_state_lock); | |
1338 | ||
79feb521 | 1339 | jbd2_write_superblock(journal, WRITE_SYNC); |
24bcc89c JK |
1340 | } |
1341 | ||
470decc6 DK |
1342 | /* |
1343 | * Read the superblock for a given journal, performing initial | |
1344 | * validation of the format. | |
1345 | */ | |
470decc6 DK |
1346 | static int journal_get_superblock(journal_t *journal) |
1347 | { | |
1348 | struct buffer_head *bh; | |
1349 | journal_superblock_t *sb; | |
1350 | int err = -EIO; | |
1351 | ||
1352 | bh = journal->j_sb_buffer; | |
1353 | ||
1354 | J_ASSERT(bh != NULL); | |
1355 | if (!buffer_uptodate(bh)) { | |
1356 | ll_rw_block(READ, 1, &bh); | |
1357 | wait_on_buffer(bh); | |
1358 | if (!buffer_uptodate(bh)) { | |
f2a44523 EG |
1359 | printk(KERN_ERR |
1360 | "JBD2: IO error reading journal superblock\n"); | |
470decc6 DK |
1361 | goto out; |
1362 | } | |
1363 | } | |
1364 | ||
1365 | sb = journal->j_superblock; | |
1366 | ||
1367 | err = -EINVAL; | |
1368 | ||
f7f4bccb | 1369 | if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) || |
470decc6 | 1370 | sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) { |
f2a44523 | 1371 | printk(KERN_WARNING "JBD2: no valid journal superblock found\n"); |
470decc6 DK |
1372 | goto out; |
1373 | } | |
1374 | ||
1375 | switch(be32_to_cpu(sb->s_header.h_blocktype)) { | |
f7f4bccb | 1376 | case JBD2_SUPERBLOCK_V1: |
470decc6 DK |
1377 | journal->j_format_version = 1; |
1378 | break; | |
f7f4bccb | 1379 | case JBD2_SUPERBLOCK_V2: |
470decc6 DK |
1380 | journal->j_format_version = 2; |
1381 | break; | |
1382 | default: | |
f2a44523 | 1383 | printk(KERN_WARNING "JBD2: unrecognised superblock format ID\n"); |
470decc6 DK |
1384 | goto out; |
1385 | } | |
1386 | ||
1387 | if (be32_to_cpu(sb->s_maxlen) < journal->j_maxlen) | |
1388 | journal->j_maxlen = be32_to_cpu(sb->s_maxlen); | |
1389 | else if (be32_to_cpu(sb->s_maxlen) > journal->j_maxlen) { | |
f2a44523 | 1390 | printk(KERN_WARNING "JBD2: journal file too short\n"); |
470decc6 DK |
1391 | goto out; |
1392 | } | |
1393 | ||
8762202d EG |
1394 | if (be32_to_cpu(sb->s_first) == 0 || |
1395 | be32_to_cpu(sb->s_first) >= journal->j_maxlen) { | |
1396 | printk(KERN_WARNING | |
1397 | "JBD2: Invalid start block of journal: %u\n", | |
1398 | be32_to_cpu(sb->s_first)); | |
1399 | goto out; | |
1400 | } | |
1401 | ||
470decc6 DK |
1402 | return 0; |
1403 | ||
1404 | out: | |
1405 | journal_fail_superblock(journal); | |
1406 | return err; | |
1407 | } | |
1408 | ||
1409 | /* | |
1410 | * Load the on-disk journal superblock and read the key fields into the | |
1411 | * journal_t. | |
1412 | */ | |
1413 | ||
1414 | static int load_superblock(journal_t *journal) | |
1415 | { | |
1416 | int err; | |
1417 | journal_superblock_t *sb; | |
1418 | ||
1419 | err = journal_get_superblock(journal); | |
1420 | if (err) | |
1421 | return err; | |
1422 | ||
1423 | sb = journal->j_superblock; | |
1424 | ||
1425 | journal->j_tail_sequence = be32_to_cpu(sb->s_sequence); | |
1426 | journal->j_tail = be32_to_cpu(sb->s_start); | |
1427 | journal->j_first = be32_to_cpu(sb->s_first); | |
1428 | journal->j_last = be32_to_cpu(sb->s_maxlen); | |
1429 | journal->j_errno = be32_to_cpu(sb->s_errno); | |
1430 | ||
1431 | return 0; | |
1432 | } | |
1433 | ||
1434 | ||
1435 | /** | |
f7f4bccb | 1436 | * int jbd2_journal_load() - Read journal from disk. |
470decc6 DK |
1437 | * @journal: Journal to act on. |
1438 | * | |
1439 | * Given a journal_t structure which tells us which disk blocks contain | |
1440 | * a journal, read the journal from disk to initialise the in-memory | |
1441 | * structures. | |
1442 | */ | |
f7f4bccb | 1443 | int jbd2_journal_load(journal_t *journal) |
470decc6 DK |
1444 | { |
1445 | int err; | |
1446 | journal_superblock_t *sb; | |
1447 | ||
1448 | err = load_superblock(journal); | |
1449 | if (err) | |
1450 | return err; | |
1451 | ||
1452 | sb = journal->j_superblock; | |
1453 | /* If this is a V2 superblock, then we have to check the | |
1454 | * features flags on it. */ | |
1455 | ||
1456 | if (journal->j_format_version >= 2) { | |
1457 | if ((sb->s_feature_ro_compat & | |
f7f4bccb | 1458 | ~cpu_to_be32(JBD2_KNOWN_ROCOMPAT_FEATURES)) || |
470decc6 | 1459 | (sb->s_feature_incompat & |
f7f4bccb | 1460 | ~cpu_to_be32(JBD2_KNOWN_INCOMPAT_FEATURES))) { |
f2a44523 EG |
1461 | printk(KERN_WARNING |
1462 | "JBD2: Unrecognised features on journal\n"); | |
470decc6 DK |
1463 | return -EINVAL; |
1464 | } | |
1465 | } | |
1466 | ||
d2eecb03 TT |
1467 | /* |
1468 | * Create a slab for this blocksize | |
1469 | */ | |
1470 | err = jbd2_journal_create_slab(be32_to_cpu(sb->s_blocksize)); | |
1471 | if (err) | |
1472 | return err; | |
1473 | ||
470decc6 DK |
1474 | /* Let the recovery code check whether it needs to recover any |
1475 | * data from the journal. */ | |
f7f4bccb | 1476 | if (jbd2_journal_recover(journal)) |
470decc6 DK |
1477 | goto recovery_error; |
1478 | ||
e6a47428 TT |
1479 | if (journal->j_failed_commit) { |
1480 | printk(KERN_ERR "JBD2: journal transaction %u on %s " | |
1481 | "is corrupt.\n", journal->j_failed_commit, | |
1482 | journal->j_devname); | |
1483 | return -EIO; | |
1484 | } | |
1485 | ||
470decc6 DK |
1486 | /* OK, we've finished with the dynamic journal bits: |
1487 | * reinitialise the dynamic contents of the superblock in memory | |
1488 | * and reset them on disk. */ | |
1489 | if (journal_reset(journal)) | |
1490 | goto recovery_error; | |
1491 | ||
f7f4bccb MC |
1492 | journal->j_flags &= ~JBD2_ABORT; |
1493 | journal->j_flags |= JBD2_LOADED; | |
470decc6 DK |
1494 | return 0; |
1495 | ||
1496 | recovery_error: | |
f2a44523 | 1497 | printk(KERN_WARNING "JBD2: recovery failed\n"); |
470decc6 DK |
1498 | return -EIO; |
1499 | } | |
1500 | ||
1501 | /** | |
f7f4bccb | 1502 | * void jbd2_journal_destroy() - Release a journal_t structure. |
470decc6 DK |
1503 | * @journal: Journal to act on. |
1504 | * | |
1505 | * Release a journal_t structure once it is no longer in use by the | |
1506 | * journaled object. | |
44519faf | 1507 | * Return <0 if we couldn't clean up the journal. |
470decc6 | 1508 | */ |
44519faf | 1509 | int jbd2_journal_destroy(journal_t *journal) |
470decc6 | 1510 | { |
44519faf HK |
1511 | int err = 0; |
1512 | ||
470decc6 DK |
1513 | /* Wait for the commit thread to wake up and die. */ |
1514 | journal_kill_thread(journal); | |
1515 | ||
1516 | /* Force a final log commit */ | |
1517 | if (journal->j_running_transaction) | |
f7f4bccb | 1518 | jbd2_journal_commit_transaction(journal); |
470decc6 DK |
1519 | |
1520 | /* Force any old transactions to disk */ | |
1521 | ||
1522 | /* Totally anal locking here... */ | |
1523 | spin_lock(&journal->j_list_lock); | |
1524 | while (journal->j_checkpoint_transactions != NULL) { | |
1525 | spin_unlock(&journal->j_list_lock); | |
1a0d3786 | 1526 | mutex_lock(&journal->j_checkpoint_mutex); |
f7f4bccb | 1527 | jbd2_log_do_checkpoint(journal); |
1a0d3786 | 1528 | mutex_unlock(&journal->j_checkpoint_mutex); |
470decc6 DK |
1529 | spin_lock(&journal->j_list_lock); |
1530 | } | |
1531 | ||
1532 | J_ASSERT(journal->j_running_transaction == NULL); | |
1533 | J_ASSERT(journal->j_committing_transaction == NULL); | |
1534 | J_ASSERT(journal->j_checkpoint_transactions == NULL); | |
1535 | spin_unlock(&journal->j_list_lock); | |
1536 | ||
470decc6 | 1537 | if (journal->j_sb_buffer) { |
a78bb11d JK |
1538 | if (!is_journal_aborted(journal)) { |
1539 | mutex_lock(&journal->j_checkpoint_mutex); | |
24bcc89c | 1540 | jbd2_mark_journal_empty(journal); |
a78bb11d JK |
1541 | mutex_unlock(&journal->j_checkpoint_mutex); |
1542 | } else | |
44519faf | 1543 | err = -EIO; |
470decc6 DK |
1544 | brelse(journal->j_sb_buffer); |
1545 | } | |
1546 | ||
8e85fb3f JL |
1547 | if (journal->j_proc_entry) |
1548 | jbd2_stats_proc_exit(journal); | |
470decc6 DK |
1549 | if (journal->j_inode) |
1550 | iput(journal->j_inode); | |
1551 | if (journal->j_revoke) | |
f7f4bccb | 1552 | jbd2_journal_destroy_revoke(journal); |
470decc6 DK |
1553 | kfree(journal->j_wbuf); |
1554 | kfree(journal); | |
44519faf HK |
1555 | |
1556 | return err; | |
470decc6 DK |
1557 | } |
1558 | ||
1559 | ||
1560 | /** | |
f7f4bccb | 1561 | *int jbd2_journal_check_used_features () - Check if features specified are used. |
470decc6 DK |
1562 | * @journal: Journal to check. |
1563 | * @compat: bitmask of compatible features | |
1564 | * @ro: bitmask of features that force read-only mount | |
1565 | * @incompat: bitmask of incompatible features | |
1566 | * | |
1567 | * Check whether the journal uses all of a given set of | |
1568 | * features. Return true (non-zero) if it does. | |
1569 | **/ | |
1570 | ||
f7f4bccb | 1571 | int jbd2_journal_check_used_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1572 | unsigned long ro, unsigned long incompat) |
1573 | { | |
1574 | journal_superblock_t *sb; | |
1575 | ||
1576 | if (!compat && !ro && !incompat) | |
1577 | return 1; | |
1113e1b5 PL |
1578 | /* Load journal superblock if it is not loaded yet. */ |
1579 | if (journal->j_format_version == 0 && | |
1580 | journal_get_superblock(journal) != 0) | |
1581 | return 0; | |
470decc6 DK |
1582 | if (journal->j_format_version == 1) |
1583 | return 0; | |
1584 | ||
1585 | sb = journal->j_superblock; | |
1586 | ||
1587 | if (((be32_to_cpu(sb->s_feature_compat) & compat) == compat) && | |
1588 | ((be32_to_cpu(sb->s_feature_ro_compat) & ro) == ro) && | |
1589 | ((be32_to_cpu(sb->s_feature_incompat) & incompat) == incompat)) | |
1590 | return 1; | |
1591 | ||
1592 | return 0; | |
1593 | } | |
1594 | ||
1595 | /** | |
f7f4bccb | 1596 | * int jbd2_journal_check_available_features() - Check feature set in journalling layer |
470decc6 DK |
1597 | * @journal: Journal to check. |
1598 | * @compat: bitmask of compatible features | |
1599 | * @ro: bitmask of features that force read-only mount | |
1600 | * @incompat: bitmask of incompatible features | |
1601 | * | |
1602 | * Check whether the journaling code supports the use of | |
1603 | * all of a given set of features on this journal. Return true | |
1604 | * (non-zero) if it can. */ | |
1605 | ||
f7f4bccb | 1606 | int jbd2_journal_check_available_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1607 | unsigned long ro, unsigned long incompat) |
1608 | { | |
470decc6 DK |
1609 | if (!compat && !ro && !incompat) |
1610 | return 1; | |
1611 | ||
470decc6 DK |
1612 | /* We can support any known requested features iff the |
1613 | * superblock is in version 2. Otherwise we fail to support any | |
1614 | * extended sb features. */ | |
1615 | ||
1616 | if (journal->j_format_version != 2) | |
1617 | return 0; | |
1618 | ||
f7f4bccb MC |
1619 | if ((compat & JBD2_KNOWN_COMPAT_FEATURES) == compat && |
1620 | (ro & JBD2_KNOWN_ROCOMPAT_FEATURES) == ro && | |
1621 | (incompat & JBD2_KNOWN_INCOMPAT_FEATURES) == incompat) | |
470decc6 DK |
1622 | return 1; |
1623 | ||
1624 | return 0; | |
1625 | } | |
1626 | ||
1627 | /** | |
f7f4bccb | 1628 | * int jbd2_journal_set_features () - Mark a given journal feature in the superblock |
470decc6 DK |
1629 | * @journal: Journal to act on. |
1630 | * @compat: bitmask of compatible features | |
1631 | * @ro: bitmask of features that force read-only mount | |
1632 | * @incompat: bitmask of incompatible features | |
1633 | * | |
1634 | * Mark a given journal feature as present on the | |
1635 | * superblock. Returns true if the requested features could be set. | |
1636 | * | |
1637 | */ | |
1638 | ||
f7f4bccb | 1639 | int jbd2_journal_set_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1640 | unsigned long ro, unsigned long incompat) |
1641 | { | |
1642 | journal_superblock_t *sb; | |
1643 | ||
f7f4bccb | 1644 | if (jbd2_journal_check_used_features(journal, compat, ro, incompat)) |
470decc6 DK |
1645 | return 1; |
1646 | ||
f7f4bccb | 1647 | if (!jbd2_journal_check_available_features(journal, compat, ro, incompat)) |
470decc6 DK |
1648 | return 0; |
1649 | ||
1650 | jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n", | |
1651 | compat, ro, incompat); | |
1652 | ||
1653 | sb = journal->j_superblock; | |
1654 | ||
1655 | sb->s_feature_compat |= cpu_to_be32(compat); | |
1656 | sb->s_feature_ro_compat |= cpu_to_be32(ro); | |
1657 | sb->s_feature_incompat |= cpu_to_be32(incompat); | |
1658 | ||
1659 | return 1; | |
1660 | } | |
1661 | ||
818d276c GS |
1662 | /* |
1663 | * jbd2_journal_clear_features () - Clear a given journal feature in the | |
1664 | * superblock | |
1665 | * @journal: Journal to act on. | |
1666 | * @compat: bitmask of compatible features | |
1667 | * @ro: bitmask of features that force read-only mount | |
1668 | * @incompat: bitmask of incompatible features | |
1669 | * | |
1670 | * Clear a given journal feature as present on the | |
1671 | * superblock. | |
1672 | */ | |
1673 | void jbd2_journal_clear_features(journal_t *journal, unsigned long compat, | |
1674 | unsigned long ro, unsigned long incompat) | |
1675 | { | |
1676 | journal_superblock_t *sb; | |
1677 | ||
1678 | jbd_debug(1, "Clear features 0x%lx/0x%lx/0x%lx\n", | |
1679 | compat, ro, incompat); | |
1680 | ||
1681 | sb = journal->j_superblock; | |
1682 | ||
1683 | sb->s_feature_compat &= ~cpu_to_be32(compat); | |
1684 | sb->s_feature_ro_compat &= ~cpu_to_be32(ro); | |
1685 | sb->s_feature_incompat &= ~cpu_to_be32(incompat); | |
1686 | } | |
1687 | EXPORT_SYMBOL(jbd2_journal_clear_features); | |
470decc6 | 1688 | |
470decc6 | 1689 | /** |
f7f4bccb | 1690 | * int jbd2_journal_flush () - Flush journal |
470decc6 DK |
1691 | * @journal: Journal to act on. |
1692 | * | |
1693 | * Flush all data for a given journal to disk and empty the journal. | |
1694 | * Filesystems can use this when remounting readonly to ensure that | |
1695 | * recovery does not need to happen on remount. | |
1696 | */ | |
1697 | ||
f7f4bccb | 1698 | int jbd2_journal_flush(journal_t *journal) |
470decc6 DK |
1699 | { |
1700 | int err = 0; | |
1701 | transaction_t *transaction = NULL; | |
470decc6 | 1702 | |
a931da6a | 1703 | write_lock(&journal->j_state_lock); |
470decc6 DK |
1704 | |
1705 | /* Force everything buffered to the log... */ | |
1706 | if (journal->j_running_transaction) { | |
1707 | transaction = journal->j_running_transaction; | |
f7f4bccb | 1708 | __jbd2_log_start_commit(journal, transaction->t_tid); |
470decc6 DK |
1709 | } else if (journal->j_committing_transaction) |
1710 | transaction = journal->j_committing_transaction; | |
1711 | ||
1712 | /* Wait for the log commit to complete... */ | |
1713 | if (transaction) { | |
1714 | tid_t tid = transaction->t_tid; | |
1715 | ||
a931da6a | 1716 | write_unlock(&journal->j_state_lock); |
f7f4bccb | 1717 | jbd2_log_wait_commit(journal, tid); |
470decc6 | 1718 | } else { |
a931da6a | 1719 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1720 | } |
1721 | ||
1722 | /* ...and flush everything in the log out to disk. */ | |
1723 | spin_lock(&journal->j_list_lock); | |
1724 | while (!err && journal->j_checkpoint_transactions != NULL) { | |
1725 | spin_unlock(&journal->j_list_lock); | |
44519faf | 1726 | mutex_lock(&journal->j_checkpoint_mutex); |
f7f4bccb | 1727 | err = jbd2_log_do_checkpoint(journal); |
44519faf | 1728 | mutex_unlock(&journal->j_checkpoint_mutex); |
470decc6 DK |
1729 | spin_lock(&journal->j_list_lock); |
1730 | } | |
1731 | spin_unlock(&journal->j_list_lock); | |
44519faf HK |
1732 | |
1733 | if (is_journal_aborted(journal)) | |
1734 | return -EIO; | |
1735 | ||
a78bb11d | 1736 | mutex_lock(&journal->j_checkpoint_mutex); |
f7f4bccb | 1737 | jbd2_cleanup_journal_tail(journal); |
470decc6 DK |
1738 | |
1739 | /* Finally, mark the journal as really needing no recovery. | |
1740 | * This sets s_start==0 in the underlying superblock, which is | |
1741 | * the magic code for a fully-recovered superblock. Any future | |
1742 | * commits of data to the journal will restore the current | |
1743 | * s_start value. */ | |
24bcc89c | 1744 | jbd2_mark_journal_empty(journal); |
a78bb11d | 1745 | mutex_unlock(&journal->j_checkpoint_mutex); |
a931da6a | 1746 | write_lock(&journal->j_state_lock); |
470decc6 DK |
1747 | J_ASSERT(!journal->j_running_transaction); |
1748 | J_ASSERT(!journal->j_committing_transaction); | |
1749 | J_ASSERT(!journal->j_checkpoint_transactions); | |
1750 | J_ASSERT(journal->j_head == journal->j_tail); | |
1751 | J_ASSERT(journal->j_tail_sequence == journal->j_transaction_sequence); | |
a931da6a | 1752 | write_unlock(&journal->j_state_lock); |
44519faf | 1753 | return 0; |
470decc6 DK |
1754 | } |
1755 | ||
1756 | /** | |
f7f4bccb | 1757 | * int jbd2_journal_wipe() - Wipe journal contents |
470decc6 DK |
1758 | * @journal: Journal to act on. |
1759 | * @write: flag (see below) | |
1760 | * | |
1761 | * Wipe out all of the contents of a journal, safely. This will produce | |
1762 | * a warning if the journal contains any valid recovery information. | |
f7f4bccb | 1763 | * Must be called between journal_init_*() and jbd2_journal_load(). |
470decc6 DK |
1764 | * |
1765 | * If 'write' is non-zero, then we wipe out the journal on disk; otherwise | |
1766 | * we merely suppress recovery. | |
1767 | */ | |
1768 | ||
f7f4bccb | 1769 | int jbd2_journal_wipe(journal_t *journal, int write) |
470decc6 | 1770 | { |
470decc6 DK |
1771 | int err = 0; |
1772 | ||
f7f4bccb | 1773 | J_ASSERT (!(journal->j_flags & JBD2_LOADED)); |
470decc6 DK |
1774 | |
1775 | err = load_superblock(journal); | |
1776 | if (err) | |
1777 | return err; | |
1778 | ||
470decc6 DK |
1779 | if (!journal->j_tail) |
1780 | goto no_recovery; | |
1781 | ||
f2a44523 | 1782 | printk(KERN_WARNING "JBD2: %s recovery information on journal\n", |
470decc6 DK |
1783 | write ? "Clearing" : "Ignoring"); |
1784 | ||
f7f4bccb | 1785 | err = jbd2_journal_skip_recovery(journal); |
a78bb11d JK |
1786 | if (write) { |
1787 | /* Lock to make assertions happy... */ | |
1788 | mutex_lock(&journal->j_checkpoint_mutex); | |
24bcc89c | 1789 | jbd2_mark_journal_empty(journal); |
a78bb11d JK |
1790 | mutex_unlock(&journal->j_checkpoint_mutex); |
1791 | } | |
470decc6 DK |
1792 | |
1793 | no_recovery: | |
1794 | return err; | |
1795 | } | |
1796 | ||
470decc6 DK |
1797 | /* |
1798 | * Journal abort has very specific semantics, which we describe | |
1799 | * for journal abort. | |
1800 | * | |
bfcd3555 | 1801 | * Two internal functions, which provide abort to the jbd layer |
470decc6 DK |
1802 | * itself are here. |
1803 | */ | |
1804 | ||
1805 | /* | |
1806 | * Quick version for internal journal use (doesn't lock the journal). | |
1807 | * Aborts hard --- we mark the abort as occurred, but do _nothing_ else, | |
1808 | * and don't attempt to make any other journal updates. | |
1809 | */ | |
f7f4bccb | 1810 | void __jbd2_journal_abort_hard(journal_t *journal) |
470decc6 DK |
1811 | { |
1812 | transaction_t *transaction; | |
470decc6 | 1813 | |
f7f4bccb | 1814 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1815 | return; |
1816 | ||
1817 | printk(KERN_ERR "Aborting journal on device %s.\n", | |
05496769 | 1818 | journal->j_devname); |
470decc6 | 1819 | |
a931da6a | 1820 | write_lock(&journal->j_state_lock); |
f7f4bccb | 1821 | journal->j_flags |= JBD2_ABORT; |
470decc6 DK |
1822 | transaction = journal->j_running_transaction; |
1823 | if (transaction) | |
f7f4bccb | 1824 | __jbd2_log_start_commit(journal, transaction->t_tid); |
a931da6a | 1825 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1826 | } |
1827 | ||
1828 | /* Soft abort: record the abort error status in the journal superblock, | |
1829 | * but don't do any other IO. */ | |
1830 | static void __journal_abort_soft (journal_t *journal, int errno) | |
1831 | { | |
f7f4bccb | 1832 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1833 | return; |
1834 | ||
1835 | if (!journal->j_errno) | |
1836 | journal->j_errno = errno; | |
1837 | ||
f7f4bccb | 1838 | __jbd2_journal_abort_hard(journal); |
470decc6 DK |
1839 | |
1840 | if (errno) | |
24bcc89c | 1841 | jbd2_journal_update_sb_errno(journal); |
470decc6 DK |
1842 | } |
1843 | ||
1844 | /** | |
f7f4bccb | 1845 | * void jbd2_journal_abort () - Shutdown the journal immediately. |
470decc6 DK |
1846 | * @journal: the journal to shutdown. |
1847 | * @errno: an error number to record in the journal indicating | |
1848 | * the reason for the shutdown. | |
1849 | * | |
1850 | * Perform a complete, immediate shutdown of the ENTIRE | |
1851 | * journal (not of a single transaction). This operation cannot be | |
1852 | * undone without closing and reopening the journal. | |
1853 | * | |
f7f4bccb | 1854 | * The jbd2_journal_abort function is intended to support higher level error |
470decc6 DK |
1855 | * recovery mechanisms such as the ext2/ext3 remount-readonly error |
1856 | * mode. | |
1857 | * | |
1858 | * Journal abort has very specific semantics. Any existing dirty, | |
1859 | * unjournaled buffers in the main filesystem will still be written to | |
1860 | * disk by bdflush, but the journaling mechanism will be suspended | |
1861 | * immediately and no further transaction commits will be honoured. | |
1862 | * | |
1863 | * Any dirty, journaled buffers will be written back to disk without | |
1864 | * hitting the journal. Atomicity cannot be guaranteed on an aborted | |
1865 | * filesystem, but we _do_ attempt to leave as much data as possible | |
1866 | * behind for fsck to use for cleanup. | |
1867 | * | |
1868 | * Any attempt to get a new transaction handle on a journal which is in | |
1869 | * ABORT state will just result in an -EROFS error return. A | |
f7f4bccb | 1870 | * jbd2_journal_stop on an existing handle will return -EIO if we have |
470decc6 DK |
1871 | * entered abort state during the update. |
1872 | * | |
1873 | * Recursive transactions are not disturbed by journal abort until the | |
f7f4bccb | 1874 | * final jbd2_journal_stop, which will receive the -EIO error. |
470decc6 | 1875 | * |
f7f4bccb | 1876 | * Finally, the jbd2_journal_abort call allows the caller to supply an errno |
470decc6 DK |
1877 | * which will be recorded (if possible) in the journal superblock. This |
1878 | * allows a client to record failure conditions in the middle of a | |
1879 | * transaction without having to complete the transaction to record the | |
1880 | * failure to disk. ext3_error, for example, now uses this | |
1881 | * functionality. | |
1882 | * | |
1883 | * Errors which originate from within the journaling layer will NOT | |
1884 | * supply an errno; a null errno implies that absolutely no further | |
1885 | * writes are done to the journal (unless there are any already in | |
1886 | * progress). | |
1887 | * | |
1888 | */ | |
1889 | ||
f7f4bccb | 1890 | void jbd2_journal_abort(journal_t *journal, int errno) |
470decc6 DK |
1891 | { |
1892 | __journal_abort_soft(journal, errno); | |
1893 | } | |
1894 | ||
1895 | /** | |
f7f4bccb | 1896 | * int jbd2_journal_errno () - returns the journal's error state. |
470decc6 DK |
1897 | * @journal: journal to examine. |
1898 | * | |
bfcd3555 | 1899 | * This is the errno number set with jbd2_journal_abort(), the last |
470decc6 DK |
1900 | * time the journal was mounted - if the journal was stopped |
1901 | * without calling abort this will be 0. | |
1902 | * | |
1903 | * If the journal has been aborted on this mount time -EROFS will | |
1904 | * be returned. | |
1905 | */ | |
f7f4bccb | 1906 | int jbd2_journal_errno(journal_t *journal) |
470decc6 DK |
1907 | { |
1908 | int err; | |
1909 | ||
a931da6a | 1910 | read_lock(&journal->j_state_lock); |
f7f4bccb | 1911 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1912 | err = -EROFS; |
1913 | else | |
1914 | err = journal->j_errno; | |
a931da6a | 1915 | read_unlock(&journal->j_state_lock); |
470decc6 DK |
1916 | return err; |
1917 | } | |
1918 | ||
1919 | /** | |
f7f4bccb | 1920 | * int jbd2_journal_clear_err () - clears the journal's error state |
470decc6 DK |
1921 | * @journal: journal to act on. |
1922 | * | |
bfcd3555 | 1923 | * An error must be cleared or acked to take a FS out of readonly |
470decc6 DK |
1924 | * mode. |
1925 | */ | |
f7f4bccb | 1926 | int jbd2_journal_clear_err(journal_t *journal) |
470decc6 DK |
1927 | { |
1928 | int err = 0; | |
1929 | ||
a931da6a | 1930 | write_lock(&journal->j_state_lock); |
f7f4bccb | 1931 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1932 | err = -EROFS; |
1933 | else | |
1934 | journal->j_errno = 0; | |
a931da6a | 1935 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1936 | return err; |
1937 | } | |
1938 | ||
1939 | /** | |
f7f4bccb | 1940 | * void jbd2_journal_ack_err() - Ack journal err. |
470decc6 DK |
1941 | * @journal: journal to act on. |
1942 | * | |
bfcd3555 | 1943 | * An error must be cleared or acked to take a FS out of readonly |
470decc6 DK |
1944 | * mode. |
1945 | */ | |
f7f4bccb | 1946 | void jbd2_journal_ack_err(journal_t *journal) |
470decc6 | 1947 | { |
a931da6a | 1948 | write_lock(&journal->j_state_lock); |
470decc6 | 1949 | if (journal->j_errno) |
f7f4bccb | 1950 | journal->j_flags |= JBD2_ACK_ERR; |
a931da6a | 1951 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1952 | } |
1953 | ||
f7f4bccb | 1954 | int jbd2_journal_blocks_per_page(struct inode *inode) |
470decc6 DK |
1955 | { |
1956 | return 1 << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
1957 | } | |
1958 | ||
b517bea1 ZB |
1959 | /* |
1960 | * helper functions to deal with 32 or 64bit block numbers. | |
1961 | */ | |
1962 | size_t journal_tag_bytes(journal_t *journal) | |
1963 | { | |
1964 | if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT)) | |
cd02ff0b | 1965 | return JBD2_TAG_SIZE64; |
b517bea1 | 1966 | else |
cd02ff0b | 1967 | return JBD2_TAG_SIZE32; |
b517bea1 ZB |
1968 | } |
1969 | ||
d2eecb03 TT |
1970 | /* |
1971 | * JBD memory management | |
1972 | * | |
1973 | * These functions are used to allocate block-sized chunks of memory | |
1974 | * used for making copies of buffer_head data. Very often it will be | |
1975 | * page-sized chunks of data, but sometimes it will be in | |
1976 | * sub-page-size chunks. (For example, 16k pages on Power systems | |
1977 | * with a 4k block file system.) For blocks smaller than a page, we | |
1978 | * use a SLAB allocator. There are slab caches for each block size, | |
1979 | * which are allocated at mount time, if necessary, and we only free | |
1980 | * (all of) the slab caches when/if the jbd2 module is unloaded. For | |
1981 | * this reason we don't need to a mutex to protect access to | |
1982 | * jbd2_slab[] allocating or releasing memory; only in | |
1983 | * jbd2_journal_create_slab(). | |
1984 | */ | |
1985 | #define JBD2_MAX_SLABS 8 | |
1986 | static struct kmem_cache *jbd2_slab[JBD2_MAX_SLABS]; | |
d2eecb03 TT |
1987 | |
1988 | static const char *jbd2_slab_names[JBD2_MAX_SLABS] = { | |
1989 | "jbd2_1k", "jbd2_2k", "jbd2_4k", "jbd2_8k", | |
1990 | "jbd2_16k", "jbd2_32k", "jbd2_64k", "jbd2_128k" | |
1991 | }; | |
1992 | ||
1993 | ||
1994 | static void jbd2_journal_destroy_slabs(void) | |
1995 | { | |
1996 | int i; | |
1997 | ||
1998 | for (i = 0; i < JBD2_MAX_SLABS; i++) { | |
1999 | if (jbd2_slab[i]) | |
2000 | kmem_cache_destroy(jbd2_slab[i]); | |
2001 | jbd2_slab[i] = NULL; | |
2002 | } | |
2003 | } | |
2004 | ||
2005 | static int jbd2_journal_create_slab(size_t size) | |
2006 | { | |
51dfacde | 2007 | static DEFINE_MUTEX(jbd2_slab_create_mutex); |
d2eecb03 TT |
2008 | int i = order_base_2(size) - 10; |
2009 | size_t slab_size; | |
2010 | ||
2011 | if (size == PAGE_SIZE) | |
2012 | return 0; | |
2013 | ||
2014 | if (i >= JBD2_MAX_SLABS) | |
2015 | return -EINVAL; | |
2016 | ||
2017 | if (unlikely(i < 0)) | |
2018 | i = 0; | |
51dfacde | 2019 | mutex_lock(&jbd2_slab_create_mutex); |
d2eecb03 | 2020 | if (jbd2_slab[i]) { |
51dfacde | 2021 | mutex_unlock(&jbd2_slab_create_mutex); |
d2eecb03 TT |
2022 | return 0; /* Already created */ |
2023 | } | |
2024 | ||
2025 | slab_size = 1 << (i+10); | |
2026 | jbd2_slab[i] = kmem_cache_create(jbd2_slab_names[i], slab_size, | |
2027 | slab_size, 0, NULL); | |
51dfacde | 2028 | mutex_unlock(&jbd2_slab_create_mutex); |
d2eecb03 TT |
2029 | if (!jbd2_slab[i]) { |
2030 | printk(KERN_EMERG "JBD2: no memory for jbd2_slab cache\n"); | |
2031 | return -ENOMEM; | |
2032 | } | |
2033 | return 0; | |
2034 | } | |
2035 | ||
2036 | static struct kmem_cache *get_slab(size_t size) | |
2037 | { | |
2038 | int i = order_base_2(size) - 10; | |
2039 | ||
2040 | BUG_ON(i >= JBD2_MAX_SLABS); | |
2041 | if (unlikely(i < 0)) | |
2042 | i = 0; | |
8ac97b74 | 2043 | BUG_ON(jbd2_slab[i] == NULL); |
d2eecb03 TT |
2044 | return jbd2_slab[i]; |
2045 | } | |
2046 | ||
2047 | void *jbd2_alloc(size_t size, gfp_t flags) | |
2048 | { | |
2049 | void *ptr; | |
2050 | ||
2051 | BUG_ON(size & (size-1)); /* Must be a power of 2 */ | |
2052 | ||
2053 | flags |= __GFP_REPEAT; | |
2054 | if (size == PAGE_SIZE) | |
2055 | ptr = (void *)__get_free_pages(flags, 0); | |
2056 | else if (size > PAGE_SIZE) { | |
2057 | int order = get_order(size); | |
2058 | ||
2059 | if (order < 3) | |
2060 | ptr = (void *)__get_free_pages(flags, order); | |
2061 | else | |
2062 | ptr = vmalloc(size); | |
2063 | } else | |
2064 | ptr = kmem_cache_alloc(get_slab(size), flags); | |
2065 | ||
2066 | /* Check alignment; SLUB has gotten this wrong in the past, | |
2067 | * and this can lead to user data corruption! */ | |
2068 | BUG_ON(((unsigned long) ptr) & (size-1)); | |
2069 | ||
2070 | return ptr; | |
2071 | } | |
2072 | ||
2073 | void jbd2_free(void *ptr, size_t size) | |
2074 | { | |
2075 | if (size == PAGE_SIZE) { | |
2076 | free_pages((unsigned long)ptr, 0); | |
2077 | return; | |
2078 | } | |
2079 | if (size > PAGE_SIZE) { | |
2080 | int order = get_order(size); | |
2081 | ||
2082 | if (order < 3) | |
2083 | free_pages((unsigned long)ptr, order); | |
2084 | else | |
2085 | vfree(ptr); | |
2086 | return; | |
2087 | } | |
2088 | kmem_cache_free(get_slab(size), ptr); | |
2089 | }; | |
2090 | ||
470decc6 DK |
2091 | /* |
2092 | * Journal_head storage management | |
2093 | */ | |
e18b890b | 2094 | static struct kmem_cache *jbd2_journal_head_cache; |
e23291b9 | 2095 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
2096 | static atomic_t nr_journal_heads = ATOMIC_INIT(0); |
2097 | #endif | |
2098 | ||
4185a2ac | 2099 | static int jbd2_journal_init_journal_head_cache(void) |
470decc6 DK |
2100 | { |
2101 | int retval; | |
2102 | ||
1076d17a | 2103 | J_ASSERT(jbd2_journal_head_cache == NULL); |
a920e941 | 2104 | jbd2_journal_head_cache = kmem_cache_create("jbd2_journal_head", |
470decc6 DK |
2105 | sizeof(struct journal_head), |
2106 | 0, /* offset */ | |
77160957 | 2107 | SLAB_TEMPORARY, /* flags */ |
20c2df83 | 2108 | NULL); /* ctor */ |
470decc6 | 2109 | retval = 0; |
1076d17a | 2110 | if (!jbd2_journal_head_cache) { |
470decc6 | 2111 | retval = -ENOMEM; |
f2a44523 | 2112 | printk(KERN_EMERG "JBD2: no memory for journal_head cache\n"); |
470decc6 DK |
2113 | } |
2114 | return retval; | |
2115 | } | |
2116 | ||
4185a2ac | 2117 | static void jbd2_journal_destroy_journal_head_cache(void) |
470decc6 | 2118 | { |
8a9362eb DG |
2119 | if (jbd2_journal_head_cache) { |
2120 | kmem_cache_destroy(jbd2_journal_head_cache); | |
2121 | jbd2_journal_head_cache = NULL; | |
2122 | } | |
470decc6 DK |
2123 | } |
2124 | ||
2125 | /* | |
2126 | * journal_head splicing and dicing | |
2127 | */ | |
2128 | static struct journal_head *journal_alloc_journal_head(void) | |
2129 | { | |
2130 | struct journal_head *ret; | |
470decc6 | 2131 | |
e23291b9 | 2132 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
2133 | atomic_inc(&nr_journal_heads); |
2134 | #endif | |
f7f4bccb | 2135 | ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS); |
1076d17a | 2136 | if (!ret) { |
470decc6 | 2137 | jbd_debug(1, "out of memory for journal_head\n"); |
670be5a7 | 2138 | pr_notice_ratelimited("ENOMEM in %s, retrying.\n", __func__); |
1076d17a | 2139 | while (!ret) { |
470decc6 | 2140 | yield(); |
f7f4bccb | 2141 | ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS); |
470decc6 DK |
2142 | } |
2143 | } | |
2144 | return ret; | |
2145 | } | |
2146 | ||
2147 | static void journal_free_journal_head(struct journal_head *jh) | |
2148 | { | |
e23291b9 | 2149 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 | 2150 | atomic_dec(&nr_journal_heads); |
cd02ff0b | 2151 | memset(jh, JBD2_POISON_FREE, sizeof(*jh)); |
470decc6 | 2152 | #endif |
f7f4bccb | 2153 | kmem_cache_free(jbd2_journal_head_cache, jh); |
470decc6 DK |
2154 | } |
2155 | ||
2156 | /* | |
2157 | * A journal_head is attached to a buffer_head whenever JBD has an | |
2158 | * interest in the buffer. | |
2159 | * | |
2160 | * Whenever a buffer has an attached journal_head, its ->b_state:BH_JBD bit | |
2161 | * is set. This bit is tested in core kernel code where we need to take | |
2162 | * JBD-specific actions. Testing the zeroness of ->b_private is not reliable | |
2163 | * there. | |
2164 | * | |
2165 | * When a buffer has its BH_JBD bit set, its ->b_count is elevated by one. | |
2166 | * | |
2167 | * When a buffer has its BH_JBD bit set it is immune from being released by | |
2168 | * core kernel code, mainly via ->b_count. | |
2169 | * | |
de1b7941 JK |
2170 | * A journal_head is detached from its buffer_head when the journal_head's |
2171 | * b_jcount reaches zero. Running transaction (b_transaction) and checkpoint | |
2172 | * transaction (b_cp_transaction) hold their references to b_jcount. | |
470decc6 DK |
2173 | * |
2174 | * Various places in the kernel want to attach a journal_head to a buffer_head | |
2175 | * _before_ attaching the journal_head to a transaction. To protect the | |
f7f4bccb | 2176 | * journal_head in this situation, jbd2_journal_add_journal_head elevates the |
470decc6 | 2177 | * journal_head's b_jcount refcount by one. The caller must call |
f7f4bccb | 2178 | * jbd2_journal_put_journal_head() to undo this. |
470decc6 DK |
2179 | * |
2180 | * So the typical usage would be: | |
2181 | * | |
2182 | * (Attach a journal_head if needed. Increments b_jcount) | |
f7f4bccb | 2183 | * struct journal_head *jh = jbd2_journal_add_journal_head(bh); |
470decc6 | 2184 | * ... |
de1b7941 JK |
2185 | * (Get another reference for transaction) |
2186 | * jbd2_journal_grab_journal_head(bh); | |
470decc6 | 2187 | * jh->b_transaction = xxx; |
de1b7941 | 2188 | * (Put original reference) |
f7f4bccb | 2189 | * jbd2_journal_put_journal_head(jh); |
470decc6 DK |
2190 | */ |
2191 | ||
2192 | /* | |
2193 | * Give a buffer_head a journal_head. | |
2194 | * | |
470decc6 DK |
2195 | * May sleep. |
2196 | */ | |
f7f4bccb | 2197 | struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh) |
470decc6 DK |
2198 | { |
2199 | struct journal_head *jh; | |
2200 | struct journal_head *new_jh = NULL; | |
2201 | ||
2202 | repeat: | |
2203 | if (!buffer_jbd(bh)) { | |
2204 | new_jh = journal_alloc_journal_head(); | |
2205 | memset(new_jh, 0, sizeof(*new_jh)); | |
2206 | } | |
2207 | ||
2208 | jbd_lock_bh_journal_head(bh); | |
2209 | if (buffer_jbd(bh)) { | |
2210 | jh = bh2jh(bh); | |
2211 | } else { | |
2212 | J_ASSERT_BH(bh, | |
2213 | (atomic_read(&bh->b_count) > 0) || | |
2214 | (bh->b_page && bh->b_page->mapping)); | |
2215 | ||
2216 | if (!new_jh) { | |
2217 | jbd_unlock_bh_journal_head(bh); | |
2218 | goto repeat; | |
2219 | } | |
2220 | ||
2221 | jh = new_jh; | |
2222 | new_jh = NULL; /* We consumed it */ | |
2223 | set_buffer_jbd(bh); | |
2224 | bh->b_private = jh; | |
2225 | jh->b_bh = bh; | |
2226 | get_bh(bh); | |
2227 | BUFFER_TRACE(bh, "added journal_head"); | |
2228 | } | |
2229 | jh->b_jcount++; | |
2230 | jbd_unlock_bh_journal_head(bh); | |
2231 | if (new_jh) | |
2232 | journal_free_journal_head(new_jh); | |
2233 | return bh->b_private; | |
2234 | } | |
2235 | ||
2236 | /* | |
2237 | * Grab a ref against this buffer_head's journal_head. If it ended up not | |
2238 | * having a journal_head, return NULL | |
2239 | */ | |
f7f4bccb | 2240 | struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh) |
470decc6 DK |
2241 | { |
2242 | struct journal_head *jh = NULL; | |
2243 | ||
2244 | jbd_lock_bh_journal_head(bh); | |
2245 | if (buffer_jbd(bh)) { | |
2246 | jh = bh2jh(bh); | |
2247 | jh->b_jcount++; | |
2248 | } | |
2249 | jbd_unlock_bh_journal_head(bh); | |
2250 | return jh; | |
2251 | } | |
2252 | ||
2253 | static void __journal_remove_journal_head(struct buffer_head *bh) | |
2254 | { | |
2255 | struct journal_head *jh = bh2jh(bh); | |
2256 | ||
2257 | J_ASSERT_JH(jh, jh->b_jcount >= 0); | |
de1b7941 JK |
2258 | J_ASSERT_JH(jh, jh->b_transaction == NULL); |
2259 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); | |
2260 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); | |
2261 | J_ASSERT_JH(jh, jh->b_jlist == BJ_None); | |
2262 | J_ASSERT_BH(bh, buffer_jbd(bh)); | |
2263 | J_ASSERT_BH(bh, jh2bh(jh) == bh); | |
2264 | BUFFER_TRACE(bh, "remove journal_head"); | |
2265 | if (jh->b_frozen_data) { | |
2266 | printk(KERN_WARNING "%s: freeing b_frozen_data\n", __func__); | |
2267 | jbd2_free(jh->b_frozen_data, bh->b_size); | |
470decc6 | 2268 | } |
de1b7941 JK |
2269 | if (jh->b_committed_data) { |
2270 | printk(KERN_WARNING "%s: freeing b_committed_data\n", __func__); | |
2271 | jbd2_free(jh->b_committed_data, bh->b_size); | |
2272 | } | |
2273 | bh->b_private = NULL; | |
2274 | jh->b_bh = NULL; /* debug, really */ | |
2275 | clear_buffer_jbd(bh); | |
2276 | journal_free_journal_head(jh); | |
470decc6 DK |
2277 | } |
2278 | ||
2279 | /* | |
de1b7941 | 2280 | * Drop a reference on the passed journal_head. If it fell to zero then |
470decc6 DK |
2281 | * release the journal_head from the buffer_head. |
2282 | */ | |
f7f4bccb | 2283 | void jbd2_journal_put_journal_head(struct journal_head *jh) |
470decc6 DK |
2284 | { |
2285 | struct buffer_head *bh = jh2bh(jh); | |
2286 | ||
2287 | jbd_lock_bh_journal_head(bh); | |
2288 | J_ASSERT_JH(jh, jh->b_jcount > 0); | |
2289 | --jh->b_jcount; | |
de1b7941 | 2290 | if (!jh->b_jcount) { |
470decc6 | 2291 | __journal_remove_journal_head(bh); |
de1b7941 | 2292 | jbd_unlock_bh_journal_head(bh); |
470decc6 | 2293 | __brelse(bh); |
de1b7941 JK |
2294 | } else |
2295 | jbd_unlock_bh_journal_head(bh); | |
470decc6 DK |
2296 | } |
2297 | ||
c851ed54 JK |
2298 | /* |
2299 | * Initialize jbd inode head | |
2300 | */ | |
2301 | void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode) | |
2302 | { | |
2303 | jinode->i_transaction = NULL; | |
2304 | jinode->i_next_transaction = NULL; | |
2305 | jinode->i_vfs_inode = inode; | |
2306 | jinode->i_flags = 0; | |
2307 | INIT_LIST_HEAD(&jinode->i_list); | |
2308 | } | |
2309 | ||
2310 | /* | |
2311 | * Function to be called before we start removing inode from memory (i.e., | |
2312 | * clear_inode() is a fine place to be called from). It removes inode from | |
2313 | * transaction's lists. | |
2314 | */ | |
2315 | void jbd2_journal_release_jbd_inode(journal_t *journal, | |
2316 | struct jbd2_inode *jinode) | |
2317 | { | |
c851ed54 JK |
2318 | if (!journal) |
2319 | return; | |
2320 | restart: | |
2321 | spin_lock(&journal->j_list_lock); | |
2322 | /* Is commit writing out inode - we have to wait */ | |
39e3ac25 | 2323 | if (test_bit(__JI_COMMIT_RUNNING, &jinode->i_flags)) { |
c851ed54 JK |
2324 | wait_queue_head_t *wq; |
2325 | DEFINE_WAIT_BIT(wait, &jinode->i_flags, __JI_COMMIT_RUNNING); | |
2326 | wq = bit_waitqueue(&jinode->i_flags, __JI_COMMIT_RUNNING); | |
2327 | prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE); | |
2328 | spin_unlock(&journal->j_list_lock); | |
2329 | schedule(); | |
2330 | finish_wait(wq, &wait.wait); | |
2331 | goto restart; | |
2332 | } | |
2333 | ||
c851ed54 JK |
2334 | if (jinode->i_transaction) { |
2335 | list_del(&jinode->i_list); | |
2336 | jinode->i_transaction = NULL; | |
2337 | } | |
2338 | spin_unlock(&journal->j_list_lock); | |
2339 | } | |
2340 | ||
470decc6 | 2341 | /* |
0f49d5d0 | 2342 | * debugfs tunables |
470decc6 | 2343 | */ |
6f38c74f JS |
2344 | #ifdef CONFIG_JBD2_DEBUG |
2345 | u8 jbd2_journal_enable_debug __read_mostly; | |
f7f4bccb | 2346 | EXPORT_SYMBOL(jbd2_journal_enable_debug); |
470decc6 | 2347 | |
0f49d5d0 | 2348 | #define JBD2_DEBUG_NAME "jbd2-debug" |
470decc6 | 2349 | |
6f38c74f JS |
2350 | static struct dentry *jbd2_debugfs_dir; |
2351 | static struct dentry *jbd2_debug; | |
470decc6 | 2352 | |
0f49d5d0 JS |
2353 | static void __init jbd2_create_debugfs_entry(void) |
2354 | { | |
2355 | jbd2_debugfs_dir = debugfs_create_dir("jbd2", NULL); | |
2356 | if (jbd2_debugfs_dir) | |
765f8361 YK |
2357 | jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME, |
2358 | S_IRUGO | S_IWUSR, | |
0f49d5d0 JS |
2359 | jbd2_debugfs_dir, |
2360 | &jbd2_journal_enable_debug); | |
470decc6 DK |
2361 | } |
2362 | ||
0f49d5d0 | 2363 | static void __exit jbd2_remove_debugfs_entry(void) |
470decc6 | 2364 | { |
6f38c74f JS |
2365 | debugfs_remove(jbd2_debug); |
2366 | debugfs_remove(jbd2_debugfs_dir); | |
470decc6 DK |
2367 | } |
2368 | ||
0f49d5d0 | 2369 | #else |
470decc6 | 2370 | |
0f49d5d0 | 2371 | static void __init jbd2_create_debugfs_entry(void) |
470decc6 | 2372 | { |
470decc6 DK |
2373 | } |
2374 | ||
0f49d5d0 | 2375 | static void __exit jbd2_remove_debugfs_entry(void) |
470decc6 | 2376 | { |
470decc6 DK |
2377 | } |
2378 | ||
470decc6 DK |
2379 | #endif |
2380 | ||
8e85fb3f JL |
2381 | #ifdef CONFIG_PROC_FS |
2382 | ||
2383 | #define JBD2_STATS_PROC_NAME "fs/jbd2" | |
2384 | ||
2385 | static void __init jbd2_create_jbd_stats_proc_entry(void) | |
2386 | { | |
2387 | proc_jbd2_stats = proc_mkdir(JBD2_STATS_PROC_NAME, NULL); | |
2388 | } | |
2389 | ||
2390 | static void __exit jbd2_remove_jbd_stats_proc_entry(void) | |
2391 | { | |
2392 | if (proc_jbd2_stats) | |
2393 | remove_proc_entry(JBD2_STATS_PROC_NAME, NULL); | |
2394 | } | |
2395 | ||
2396 | #else | |
2397 | ||
2398 | #define jbd2_create_jbd_stats_proc_entry() do {} while (0) | |
2399 | #define jbd2_remove_jbd_stats_proc_entry() do {} while (0) | |
2400 | ||
2401 | #endif | |
2402 | ||
8aefcd55 | 2403 | struct kmem_cache *jbd2_handle_cache, *jbd2_inode_cache; |
470decc6 | 2404 | |
4185a2ac | 2405 | static int __init jbd2_journal_init_handle_cache(void) |
470decc6 | 2406 | { |
8aefcd55 | 2407 | jbd2_handle_cache = KMEM_CACHE(jbd2_journal_handle, SLAB_TEMPORARY); |
f7f4bccb | 2408 | if (jbd2_handle_cache == NULL) { |
8aefcd55 TT |
2409 | printk(KERN_EMERG "JBD2: failed to create handle cache\n"); |
2410 | return -ENOMEM; | |
2411 | } | |
2412 | jbd2_inode_cache = KMEM_CACHE(jbd2_inode, 0); | |
2413 | if (jbd2_inode_cache == NULL) { | |
2414 | printk(KERN_EMERG "JBD2: failed to create inode cache\n"); | |
2415 | kmem_cache_destroy(jbd2_handle_cache); | |
470decc6 DK |
2416 | return -ENOMEM; |
2417 | } | |
2418 | return 0; | |
2419 | } | |
2420 | ||
f7f4bccb | 2421 | static void jbd2_journal_destroy_handle_cache(void) |
470decc6 | 2422 | { |
f7f4bccb MC |
2423 | if (jbd2_handle_cache) |
2424 | kmem_cache_destroy(jbd2_handle_cache); | |
8aefcd55 TT |
2425 | if (jbd2_inode_cache) |
2426 | kmem_cache_destroy(jbd2_inode_cache); | |
2427 | ||
470decc6 DK |
2428 | } |
2429 | ||
2430 | /* | |
2431 | * Module startup and shutdown | |
2432 | */ | |
2433 | ||
2434 | static int __init journal_init_caches(void) | |
2435 | { | |
2436 | int ret; | |
2437 | ||
f7f4bccb | 2438 | ret = jbd2_journal_init_revoke_caches(); |
470decc6 | 2439 | if (ret == 0) |
4185a2ac | 2440 | ret = jbd2_journal_init_journal_head_cache(); |
470decc6 | 2441 | if (ret == 0) |
4185a2ac | 2442 | ret = jbd2_journal_init_handle_cache(); |
0c2022ec YY |
2443 | if (ret == 0) |
2444 | ret = jbd2_journal_init_transaction_cache(); | |
470decc6 DK |
2445 | return ret; |
2446 | } | |
2447 | ||
f7f4bccb | 2448 | static void jbd2_journal_destroy_caches(void) |
470decc6 | 2449 | { |
f7f4bccb | 2450 | jbd2_journal_destroy_revoke_caches(); |
4185a2ac | 2451 | jbd2_journal_destroy_journal_head_cache(); |
f7f4bccb | 2452 | jbd2_journal_destroy_handle_cache(); |
0c2022ec | 2453 | jbd2_journal_destroy_transaction_cache(); |
d2eecb03 | 2454 | jbd2_journal_destroy_slabs(); |
470decc6 DK |
2455 | } |
2456 | ||
2457 | static int __init journal_init(void) | |
2458 | { | |
2459 | int ret; | |
2460 | ||
2461 | BUILD_BUG_ON(sizeof(struct journal_superblock_s) != 1024); | |
2462 | ||
2463 | ret = journal_init_caches(); | |
620de4e1 DG |
2464 | if (ret == 0) { |
2465 | jbd2_create_debugfs_entry(); | |
2466 | jbd2_create_jbd_stats_proc_entry(); | |
2467 | } else { | |
f7f4bccb | 2468 | jbd2_journal_destroy_caches(); |
620de4e1 | 2469 | } |
470decc6 DK |
2470 | return ret; |
2471 | } | |
2472 | ||
2473 | static void __exit journal_exit(void) | |
2474 | { | |
e23291b9 | 2475 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
2476 | int n = atomic_read(&nr_journal_heads); |
2477 | if (n) | |
f2a44523 | 2478 | printk(KERN_EMERG "JBD2: leaked %d journal_heads!\n", n); |
470decc6 | 2479 | #endif |
0f49d5d0 | 2480 | jbd2_remove_debugfs_entry(); |
8e85fb3f | 2481 | jbd2_remove_jbd_stats_proc_entry(); |
f7f4bccb | 2482 | jbd2_journal_destroy_caches(); |
470decc6 DK |
2483 | } |
2484 | ||
2485 | MODULE_LICENSE("GPL"); | |
2486 | module_init(journal_init); | |
2487 | module_exit(journal_exit); | |
2488 |