Commit | Line | Data |
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1da177e4 | 1 | /* |
f30c2269 | 2 | * linux/fs/jbd/journal.c |
1da177e4 LT |
3 | * |
4 | * Written by Stephen C. Tweedie <sct@redhat.com>, 1998 | |
5 | * | |
6 | * Copyright 1998 Red Hat corp --- All Rights Reserved | |
7 | * | |
8 | * This file is part of the Linux kernel and is made available under | |
9 | * the terms of the GNU General Public License, version 2, or at your | |
10 | * option, any later version, incorporated herein by reference. | |
11 | * | |
12 | * Generic filesystem journal-writing code; part of the ext2fs | |
13 | * journaling system. | |
14 | * | |
15 | * This file manages journals: areas of disk reserved for logging | |
16 | * transactional updates. This includes the kernel journaling thread | |
17 | * which is responsible for scheduling updates to the log. | |
18 | * | |
19 | * We do not actually manage the physical storage of the journal in this | |
20 | * file: that is left to a per-journal policy function, which allows us | |
21 | * to store the journal within a filesystem-specified area for ext2 | |
22 | * journaling (ext2 can use a reserved inode for storing the log). | |
23 | */ | |
24 | ||
25 | #include <linux/module.h> | |
26 | #include <linux/time.h> | |
27 | #include <linux/fs.h> | |
28 | #include <linux/jbd.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/slab.h> | |
1da177e4 LT |
31 | #include <linux/init.h> |
32 | #include <linux/mm.h> | |
7dfb7103 | 33 | #include <linux/freezer.h> |
1da177e4 | 34 | #include <linux/pagemap.h> |
8d8c8511 | 35 | #include <linux/kthread.h> |
c9cf5528 | 36 | #include <linux/poison.h> |
8d8c8511 | 37 | #include <linux/proc_fs.h> |
c2a9159c | 38 | #include <linux/debugfs.h> |
f81e3d45 | 39 | #include <linux/ratelimit.h> |
8d8c8511 | 40 | |
99cb1a31 LC |
41 | #define CREATE_TRACE_POINTS |
42 | #include <trace/events/jbd.h> | |
43 | ||
1da177e4 LT |
44 | #include <asm/uaccess.h> |
45 | #include <asm/page.h> | |
1da177e4 LT |
46 | |
47 | EXPORT_SYMBOL(journal_start); | |
48 | EXPORT_SYMBOL(journal_restart); | |
49 | EXPORT_SYMBOL(journal_extend); | |
50 | EXPORT_SYMBOL(journal_stop); | |
51 | EXPORT_SYMBOL(journal_lock_updates); | |
52 | EXPORT_SYMBOL(journal_unlock_updates); | |
53 | EXPORT_SYMBOL(journal_get_write_access); | |
54 | EXPORT_SYMBOL(journal_get_create_access); | |
55 | EXPORT_SYMBOL(journal_get_undo_access); | |
56 | EXPORT_SYMBOL(journal_dirty_data); | |
57 | EXPORT_SYMBOL(journal_dirty_metadata); | |
58 | EXPORT_SYMBOL(journal_release_buffer); | |
59 | EXPORT_SYMBOL(journal_forget); | |
60 | #if 0 | |
61 | EXPORT_SYMBOL(journal_sync_buffer); | |
62 | #endif | |
63 | EXPORT_SYMBOL(journal_flush); | |
64 | EXPORT_SYMBOL(journal_revoke); | |
65 | ||
66 | EXPORT_SYMBOL(journal_init_dev); | |
67 | EXPORT_SYMBOL(journal_init_inode); | |
68 | EXPORT_SYMBOL(journal_update_format); | |
69 | EXPORT_SYMBOL(journal_check_used_features); | |
70 | EXPORT_SYMBOL(journal_check_available_features); | |
71 | EXPORT_SYMBOL(journal_set_features); | |
72 | EXPORT_SYMBOL(journal_create); | |
73 | EXPORT_SYMBOL(journal_load); | |
74 | EXPORT_SYMBOL(journal_destroy); | |
1da177e4 LT |
75 | EXPORT_SYMBOL(journal_abort); |
76 | EXPORT_SYMBOL(journal_errno); | |
77 | EXPORT_SYMBOL(journal_ack_err); | |
78 | EXPORT_SYMBOL(journal_clear_err); | |
79 | EXPORT_SYMBOL(log_wait_commit); | |
ff5e4b51 | 80 | EXPORT_SYMBOL(log_start_commit); |
1da177e4 LT |
81 | EXPORT_SYMBOL(journal_start_commit); |
82 | EXPORT_SYMBOL(journal_force_commit_nested); | |
83 | EXPORT_SYMBOL(journal_wipe); | |
84 | EXPORT_SYMBOL(journal_blocks_per_page); | |
85 | EXPORT_SYMBOL(journal_invalidatepage); | |
86 | EXPORT_SYMBOL(journal_try_to_free_buffers); | |
87 | EXPORT_SYMBOL(journal_force_commit); | |
88 | ||
89 | static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *); | |
022a4a7b | 90 | static void __journal_abort_soft (journal_t *journal, int errno); |
dff6825e | 91 | static const char *journal_dev_name(journal_t *journal, char *buffer); |
1da177e4 LT |
92 | |
93 | /* | |
94 | * Helper function used to manage commit timeouts | |
95 | */ | |
96 | ||
97 | static void commit_timeout(unsigned long __data) | |
98 | { | |
99 | struct task_struct * p = (struct task_struct *) __data; | |
100 | ||
101 | wake_up_process(p); | |
102 | } | |
103 | ||
1da177e4 LT |
104 | /* |
105 | * kjournald: The main thread function used to manage a logging device | |
106 | * journal. | |
107 | * | |
108 | * This kernel thread is responsible for two things: | |
109 | * | |
110 | * 1) COMMIT: Every so often we need to commit the current state of the | |
111 | * filesystem to disk. The journal thread is responsible for writing | |
112 | * all of the metadata buffers to disk. | |
113 | * | |
114 | * 2) CHECKPOINT: We cannot reuse a used section of the log file until all | |
115 | * of the data in that part of the log has been rewritten elsewhere on | |
116 | * the disk. Flushing these old buffers to reclaim space in the log is | |
117 | * known as checkpointing, and this thread is responsible for that job. | |
118 | */ | |
119 | ||
022a4a7b | 120 | static int kjournald(void *arg) |
1da177e4 | 121 | { |
e3df1898 | 122 | journal_t *journal = arg; |
1da177e4 | 123 | transaction_t *transaction; |
1da177e4 | 124 | |
e3df1898 AM |
125 | /* |
126 | * Set up an interval timer which can be used to trigger a commit wakeup | |
127 | * after the commit interval expires | |
128 | */ | |
129 | setup_timer(&journal->j_commit_timer, commit_timeout, | |
130 | (unsigned long)current); | |
1da177e4 LT |
131 | |
132 | /* Record that the journal thread is running */ | |
133 | journal->j_task = current; | |
134 | wake_up(&journal->j_wait_done_commit); | |
135 | ||
136 | printk(KERN_INFO "kjournald starting. Commit interval %ld seconds\n", | |
137 | journal->j_commit_interval / HZ); | |
138 | ||
139 | /* | |
140 | * And now, wait forever for commit wakeup events. | |
141 | */ | |
142 | spin_lock(&journal->j_state_lock); | |
143 | ||
144 | loop: | |
145 | if (journal->j_flags & JFS_UNMOUNT) | |
146 | goto end_loop; | |
147 | ||
148 | jbd_debug(1, "commit_sequence=%d, commit_request=%d\n", | |
149 | journal->j_commit_sequence, journal->j_commit_request); | |
150 | ||
151 | if (journal->j_commit_sequence != journal->j_commit_request) { | |
152 | jbd_debug(1, "OK, requests differ\n"); | |
153 | spin_unlock(&journal->j_state_lock); | |
e3df1898 | 154 | del_timer_sync(&journal->j_commit_timer); |
1da177e4 LT |
155 | journal_commit_transaction(journal); |
156 | spin_lock(&journal->j_state_lock); | |
157 | goto loop; | |
158 | } | |
159 | ||
160 | wake_up(&journal->j_wait_done_commit); | |
3e1d1d28 | 161 | if (freezing(current)) { |
1da177e4 LT |
162 | /* |
163 | * The simpler the better. Flushing journal isn't a | |
164 | * good idea, because that depends on threads that may | |
165 | * be already stopped. | |
166 | */ | |
167 | jbd_debug(1, "Now suspending kjournald\n"); | |
168 | spin_unlock(&journal->j_state_lock); | |
a0acae0e | 169 | try_to_freeze(); |
1da177e4 LT |
170 | spin_lock(&journal->j_state_lock); |
171 | } else { | |
172 | /* | |
173 | * We assume on resume that commits are already there, | |
174 | * so we don't sleep | |
175 | */ | |
176 | DEFINE_WAIT(wait); | |
177 | int should_sleep = 1; | |
178 | ||
179 | prepare_to_wait(&journal->j_wait_commit, &wait, | |
180 | TASK_INTERRUPTIBLE); | |
181 | if (journal->j_commit_sequence != journal->j_commit_request) | |
182 | should_sleep = 0; | |
183 | transaction = journal->j_running_transaction; | |
184 | if (transaction && time_after_eq(jiffies, | |
185 | transaction->t_expires)) | |
186 | should_sleep = 0; | |
cbf0d27a | 187 | if (journal->j_flags & JFS_UNMOUNT) |
e9ad5620 | 188 | should_sleep = 0; |
1da177e4 LT |
189 | if (should_sleep) { |
190 | spin_unlock(&journal->j_state_lock); | |
191 | schedule(); | |
192 | spin_lock(&journal->j_state_lock); | |
193 | } | |
194 | finish_wait(&journal->j_wait_commit, &wait); | |
195 | } | |
196 | ||
197 | jbd_debug(1, "kjournald wakes\n"); | |
198 | ||
199 | /* | |
200 | * Were we woken up by a commit wakeup event? | |
201 | */ | |
202 | transaction = journal->j_running_transaction; | |
203 | if (transaction && time_after_eq(jiffies, transaction->t_expires)) { | |
204 | journal->j_commit_request = transaction->t_tid; | |
205 | jbd_debug(1, "woke because of timeout\n"); | |
206 | } | |
207 | goto loop; | |
208 | ||
209 | end_loop: | |
210 | spin_unlock(&journal->j_state_lock); | |
e3df1898 | 211 | del_timer_sync(&journal->j_commit_timer); |
1da177e4 LT |
212 | journal->j_task = NULL; |
213 | wake_up(&journal->j_wait_done_commit); | |
214 | jbd_debug(1, "Journal thread exiting.\n"); | |
215 | return 0; | |
216 | } | |
217 | ||
97f06784 | 218 | static int journal_start_thread(journal_t *journal) |
1da177e4 | 219 | { |
97f06784 PE |
220 | struct task_struct *t; |
221 | ||
222 | t = kthread_run(kjournald, journal, "kjournald"); | |
223 | if (IS_ERR(t)) | |
224 | return PTR_ERR(t); | |
225 | ||
c80544dc | 226 | wait_event(journal->j_wait_done_commit, journal->j_task != NULL); |
97f06784 | 227 | return 0; |
1da177e4 LT |
228 | } |
229 | ||
230 | static void journal_kill_thread(journal_t *journal) | |
231 | { | |
232 | spin_lock(&journal->j_state_lock); | |
233 | journal->j_flags |= JFS_UNMOUNT; | |
234 | ||
235 | while (journal->j_task) { | |
236 | wake_up(&journal->j_wait_commit); | |
237 | spin_unlock(&journal->j_state_lock); | |
c80544dc SH |
238 | wait_event(journal->j_wait_done_commit, |
239 | journal->j_task == NULL); | |
1da177e4 LT |
240 | spin_lock(&journal->j_state_lock); |
241 | } | |
242 | spin_unlock(&journal->j_state_lock); | |
243 | } | |
244 | ||
245 | /* | |
246 | * journal_write_metadata_buffer: write a metadata buffer to the journal. | |
247 | * | |
248 | * Writes a metadata buffer to a given disk block. The actual IO is not | |
249 | * performed but a new buffer_head is constructed which labels the data | |
250 | * to be written with the correct destination disk block. | |
251 | * | |
252 | * Any magic-number escaping which needs to be done will cause a | |
253 | * copy-out here. If the buffer happens to start with the | |
254 | * JFS_MAGIC_NUMBER, then we can't write it to the log directly: the | |
255 | * magic number is only written to the log for descripter blocks. In | |
256 | * this case, we copy the data and replace the first word with 0, and we | |
257 | * return a result code which indicates that this buffer needs to be | |
258 | * marked as an escaped buffer in the corresponding log descriptor | |
259 | * block. The missing word can then be restored when the block is read | |
260 | * during recovery. | |
261 | * | |
262 | * If the source buffer has already been modified by a new transaction | |
263 | * since we took the last commit snapshot, we use the frozen copy of | |
264 | * that data for IO. If we end up using the existing buffer_head's data | |
265 | * for the write, then we *have* to lock the buffer to prevent anyone | |
266 | * else from using and possibly modifying it while the IO is in | |
267 | * progress. | |
268 | * | |
269 | * The function returns a pointer to the buffer_heads to be used for IO. | |
270 | * | |
271 | * We assume that the journal has already been locked in this function. | |
272 | * | |
273 | * Return value: | |
274 | * <0: Error | |
275 | * >=0: Finished OK | |
276 | * | |
277 | * On success: | |
278 | * Bit 0 set == escape performed on the data | |
279 | * Bit 1 set == buffer copy-out performed (kfree the data after IO) | |
280 | */ | |
281 | ||
282 | int journal_write_metadata_buffer(transaction_t *transaction, | |
283 | struct journal_head *jh_in, | |
284 | struct journal_head **jh_out, | |
9c28cbcc | 285 | unsigned int blocknr) |
1da177e4 LT |
286 | { |
287 | int need_copy_out = 0; | |
288 | int done_copy_out = 0; | |
289 | int do_escape = 0; | |
290 | char *mapped_data; | |
291 | struct buffer_head *new_bh; | |
292 | struct journal_head *new_jh; | |
293 | struct page *new_page; | |
294 | unsigned int new_offset; | |
295 | struct buffer_head *bh_in = jh2bh(jh_in); | |
f1015c44 | 296 | journal_t *journal = transaction->t_journal; |
1da177e4 LT |
297 | |
298 | /* | |
299 | * The buffer really shouldn't be locked: only the current committing | |
300 | * transaction is allowed to write it, so nobody else is allowed | |
301 | * to do any IO. | |
302 | * | |
303 | * akpm: except if we're journalling data, and write() output is | |
304 | * also part of a shared mapping, and another thread has | |
305 | * decided to launch a writepage() against this buffer. | |
306 | */ | |
307 | J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in)); | |
308 | ||
309 | new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL); | |
f1015c44 | 310 | /* keep subsequent assertions sane */ |
311 | new_bh->b_state = 0; | |
312 | init_buffer(new_bh, NULL, NULL); | |
313 | atomic_set(&new_bh->b_count, 1); | |
314 | new_jh = journal_add_journal_head(new_bh); /* This sleeps */ | |
1da177e4 LT |
315 | |
316 | /* | |
317 | * If a new transaction has already done a buffer copy-out, then | |
318 | * we use that version of the data for the commit. | |
319 | */ | |
320 | jbd_lock_bh_state(bh_in); | |
321 | repeat: | |
322 | if (jh_in->b_frozen_data) { | |
323 | done_copy_out = 1; | |
324 | new_page = virt_to_page(jh_in->b_frozen_data); | |
325 | new_offset = offset_in_page(jh_in->b_frozen_data); | |
326 | } else { | |
327 | new_page = jh2bh(jh_in)->b_page; | |
328 | new_offset = offset_in_page(jh2bh(jh_in)->b_data); | |
329 | } | |
330 | ||
331 | mapped_data = kmap_atomic(new_page, KM_USER0); | |
332 | /* | |
333 | * Check for escaping | |
334 | */ | |
335 | if (*((__be32 *)(mapped_data + new_offset)) == | |
336 | cpu_to_be32(JFS_MAGIC_NUMBER)) { | |
337 | need_copy_out = 1; | |
338 | do_escape = 1; | |
339 | } | |
340 | kunmap_atomic(mapped_data, KM_USER0); | |
341 | ||
342 | /* | |
343 | * Do we need to do a data copy? | |
344 | */ | |
345 | if (need_copy_out && !done_copy_out) { | |
346 | char *tmp; | |
347 | ||
348 | jbd_unlock_bh_state(bh_in); | |
c089d490 | 349 | tmp = jbd_alloc(bh_in->b_size, GFP_NOFS); |
1da177e4 LT |
350 | jbd_lock_bh_state(bh_in); |
351 | if (jh_in->b_frozen_data) { | |
c089d490 | 352 | jbd_free(tmp, bh_in->b_size); |
1da177e4 LT |
353 | goto repeat; |
354 | } | |
355 | ||
356 | jh_in->b_frozen_data = tmp; | |
357 | mapped_data = kmap_atomic(new_page, KM_USER0); | |
358 | memcpy(tmp, mapped_data + new_offset, jh2bh(jh_in)->b_size); | |
359 | kunmap_atomic(mapped_data, KM_USER0); | |
360 | ||
361 | new_page = virt_to_page(tmp); | |
362 | new_offset = offset_in_page(tmp); | |
363 | done_copy_out = 1; | |
364 | } | |
365 | ||
366 | /* | |
367 | * Did we need to do an escaping? Now we've done all the | |
368 | * copying, we can finally do so. | |
369 | */ | |
370 | if (do_escape) { | |
371 | mapped_data = kmap_atomic(new_page, KM_USER0); | |
372 | *((unsigned int *)(mapped_data + new_offset)) = 0; | |
373 | kunmap_atomic(mapped_data, KM_USER0); | |
374 | } | |
375 | ||
1da177e4 LT |
376 | set_bh_page(new_bh, new_page, new_offset); |
377 | new_jh->b_transaction = NULL; | |
378 | new_bh->b_size = jh2bh(jh_in)->b_size; | |
379 | new_bh->b_bdev = transaction->t_journal->j_dev; | |
380 | new_bh->b_blocknr = blocknr; | |
381 | set_buffer_mapped(new_bh); | |
382 | set_buffer_dirty(new_bh); | |
383 | ||
384 | *jh_out = new_jh; | |
385 | ||
386 | /* | |
387 | * The to-be-written buffer needs to get moved to the io queue, | |
388 | * and the original buffer whose contents we are shadowing or | |
389 | * copying is moved to the transaction's shadow queue. | |
390 | */ | |
391 | JBUFFER_TRACE(jh_in, "file as BJ_Shadow"); | |
f1015c44 | 392 | spin_lock(&journal->j_list_lock); |
393 | __journal_file_buffer(jh_in, transaction, BJ_Shadow); | |
394 | spin_unlock(&journal->j_list_lock); | |
395 | jbd_unlock_bh_state(bh_in); | |
396 | ||
1da177e4 LT |
397 | JBUFFER_TRACE(new_jh, "file as BJ_IO"); |
398 | journal_file_buffer(new_jh, transaction, BJ_IO); | |
399 | ||
400 | return do_escape | (done_copy_out << 1); | |
401 | } | |
402 | ||
403 | /* | |
404 | * Allocation code for the journal file. Manage the space left in the | |
405 | * journal, so that we can begin checkpointing when appropriate. | |
406 | */ | |
407 | ||
408 | /* | |
409 | * __log_space_left: Return the number of free blocks left in the journal. | |
410 | * | |
411 | * Called with the journal already locked. | |
412 | * | |
413 | * Called under j_state_lock | |
414 | */ | |
415 | ||
416 | int __log_space_left(journal_t *journal) | |
417 | { | |
418 | int left = journal->j_free; | |
419 | ||
420 | assert_spin_locked(&journal->j_state_lock); | |
421 | ||
422 | /* | |
423 | * Be pessimistic here about the number of those free blocks which | |
424 | * might be required for log descriptor control blocks. | |
425 | */ | |
426 | ||
427 | #define MIN_LOG_RESERVED_BLOCKS 32 /* Allow for rounding errors */ | |
428 | ||
429 | left -= MIN_LOG_RESERVED_BLOCKS; | |
430 | ||
431 | if (left <= 0) | |
432 | return 0; | |
433 | left -= (left >> 3); | |
434 | return left; | |
435 | } | |
436 | ||
437 | /* | |
8fe4cd0d | 438 | * Called under j_state_lock. Returns true if a transaction commit was started. |
1da177e4 LT |
439 | */ |
440 | int __log_start_commit(journal_t *journal, tid_t target) | |
441 | { | |
442 | /* | |
d9b01934 TT |
443 | * The only transaction we can possibly wait upon is the |
444 | * currently running transaction (if it exists). Otherwise, | |
445 | * the target tid must be an old one. | |
1da177e4 | 446 | */ |
d9b01934 TT |
447 | if (journal->j_running_transaction && |
448 | journal->j_running_transaction->t_tid == target) { | |
1da177e4 | 449 | /* |
bcf3d0bc | 450 | * We want a new commit: OK, mark the request and wakeup the |
1da177e4 LT |
451 | * commit thread. We do _not_ do the commit ourselves. |
452 | */ | |
453 | ||
454 | journal->j_commit_request = target; | |
455 | jbd_debug(1, "JBD: requesting commit %d/%d\n", | |
456 | journal->j_commit_request, | |
457 | journal->j_commit_sequence); | |
458 | wake_up(&journal->j_wait_commit); | |
459 | return 1; | |
d9b01934 TT |
460 | } else if (!tid_geq(journal->j_commit_request, target)) |
461 | /* This should never happen, but if it does, preserve | |
462 | the evidence before kjournald goes into a loop and | |
463 | increments j_commit_sequence beyond all recognition. */ | |
464 | WARN_ONCE(1, "jbd: bad log_start_commit: %u %u %u %u\n", | |
465 | journal->j_commit_request, journal->j_commit_sequence, | |
466 | target, journal->j_running_transaction ? | |
467 | journal->j_running_transaction->t_tid : 0); | |
1da177e4 LT |
468 | return 0; |
469 | } | |
470 | ||
471 | int log_start_commit(journal_t *journal, tid_t tid) | |
472 | { | |
473 | int ret; | |
474 | ||
475 | spin_lock(&journal->j_state_lock); | |
476 | ret = __log_start_commit(journal, tid); | |
477 | spin_unlock(&journal->j_state_lock); | |
478 | return ret; | |
479 | } | |
480 | ||
481 | /* | |
482 | * Force and wait upon a commit if the calling process is not within | |
483 | * transaction. This is used for forcing out undo-protected data which contains | |
484 | * bitmaps, when the fs is running out of space. | |
485 | * | |
486 | * We can only force the running transaction if we don't have an active handle; | |
487 | * otherwise, we will deadlock. | |
488 | * | |
489 | * Returns true if a transaction was started. | |
490 | */ | |
491 | int journal_force_commit_nested(journal_t *journal) | |
492 | { | |
493 | transaction_t *transaction = NULL; | |
494 | tid_t tid; | |
495 | ||
496 | spin_lock(&journal->j_state_lock); | |
497 | if (journal->j_running_transaction && !current->journal_info) { | |
498 | transaction = journal->j_running_transaction; | |
499 | __log_start_commit(journal, transaction->t_tid); | |
500 | } else if (journal->j_committing_transaction) | |
501 | transaction = journal->j_committing_transaction; | |
502 | ||
503 | if (!transaction) { | |
504 | spin_unlock(&journal->j_state_lock); | |
505 | return 0; /* Nothing to retry */ | |
506 | } | |
507 | ||
508 | tid = transaction->t_tid; | |
509 | spin_unlock(&journal->j_state_lock); | |
510 | log_wait_commit(journal, tid); | |
511 | return 1; | |
512 | } | |
513 | ||
514 | /* | |
515 | * Start a commit of the current running transaction (if any). Returns true | |
8fe4cd0d JK |
516 | * if a transaction is going to be committed (or is currently already |
517 | * committing), and fills its tid in at *ptid | |
1da177e4 LT |
518 | */ |
519 | int journal_start_commit(journal_t *journal, tid_t *ptid) | |
520 | { | |
521 | int ret = 0; | |
522 | ||
523 | spin_lock(&journal->j_state_lock); | |
524 | if (journal->j_running_transaction) { | |
525 | tid_t tid = journal->j_running_transaction->t_tid; | |
526 | ||
8fe4cd0d JK |
527 | __log_start_commit(journal, tid); |
528 | /* There's a running transaction and we've just made sure | |
529 | * it's commit has been scheduled. */ | |
530 | if (ptid) | |
1da177e4 | 531 | *ptid = tid; |
8fe4cd0d JK |
532 | ret = 1; |
533 | } else if (journal->j_committing_transaction) { | |
1da177e4 LT |
534 | /* |
535 | * If ext3_write_super() recently started a commit, then we | |
536 | * have to wait for completion of that transaction | |
537 | */ | |
8fe4cd0d JK |
538 | if (ptid) |
539 | *ptid = journal->j_committing_transaction->t_tid; | |
1da177e4 LT |
540 | ret = 1; |
541 | } | |
542 | spin_unlock(&journal->j_state_lock); | |
543 | return ret; | |
544 | } | |
545 | ||
546 | /* | |
547 | * Wait for a specified commit to complete. | |
548 | * The caller may not hold the journal lock. | |
549 | */ | |
550 | int log_wait_commit(journal_t *journal, tid_t tid) | |
551 | { | |
552 | int err = 0; | |
553 | ||
554 | #ifdef CONFIG_JBD_DEBUG | |
555 | spin_lock(&journal->j_state_lock); | |
556 | if (!tid_geq(journal->j_commit_request, tid)) { | |
557 | printk(KERN_EMERG | |
558 | "%s: error: j_commit_request=%d, tid=%d\n", | |
08fc99bf | 559 | __func__, journal->j_commit_request, tid); |
1da177e4 LT |
560 | } |
561 | spin_unlock(&journal->j_state_lock); | |
562 | #endif | |
563 | spin_lock(&journal->j_state_lock); | |
564 | while (tid_gt(tid, journal->j_commit_sequence)) { | |
565 | jbd_debug(1, "JBD: want %d, j_commit_sequence=%d\n", | |
566 | tid, journal->j_commit_sequence); | |
567 | wake_up(&journal->j_wait_commit); | |
568 | spin_unlock(&journal->j_state_lock); | |
569 | wait_event(journal->j_wait_done_commit, | |
570 | !tid_gt(tid, journal->j_commit_sequence)); | |
571 | spin_lock(&journal->j_state_lock); | |
572 | } | |
573 | spin_unlock(&journal->j_state_lock); | |
574 | ||
575 | if (unlikely(is_journal_aborted(journal))) { | |
576 | printk(KERN_EMERG "journal commit I/O error\n"); | |
577 | err = -EIO; | |
578 | } | |
579 | return err; | |
580 | } | |
581 | ||
03f4d804 JK |
582 | /* |
583 | * Return 1 if a given transaction has not yet sent barrier request | |
584 | * connected with a transaction commit. If 0 is returned, transaction | |
585 | * may or may not have sent the barrier. Used to avoid sending barrier | |
586 | * twice in common cases. | |
587 | */ | |
588 | int journal_trans_will_send_data_barrier(journal_t *journal, tid_t tid) | |
589 | { | |
590 | int ret = 0; | |
591 | transaction_t *commit_trans; | |
592 | ||
593 | if (!(journal->j_flags & JFS_BARRIER)) | |
594 | return 0; | |
595 | spin_lock(&journal->j_state_lock); | |
596 | /* Transaction already committed? */ | |
597 | if (tid_geq(journal->j_commit_sequence, tid)) | |
598 | goto out; | |
599 | /* | |
600 | * Transaction is being committed and we already proceeded to | |
601 | * writing commit record? | |
602 | */ | |
603 | commit_trans = journal->j_committing_transaction; | |
604 | if (commit_trans && commit_trans->t_tid == tid && | |
605 | commit_trans->t_state >= T_COMMIT_RECORD) | |
606 | goto out; | |
607 | ret = 1; | |
608 | out: | |
609 | spin_unlock(&journal->j_state_lock); | |
610 | return ret; | |
611 | } | |
52779708 | 612 | EXPORT_SYMBOL(journal_trans_will_send_data_barrier); |
03f4d804 | 613 | |
1da177e4 LT |
614 | /* |
615 | * Log buffer allocation routines: | |
616 | */ | |
617 | ||
9c28cbcc | 618 | int journal_next_log_block(journal_t *journal, unsigned int *retp) |
1da177e4 | 619 | { |
9c28cbcc | 620 | unsigned int blocknr; |
1da177e4 LT |
621 | |
622 | spin_lock(&journal->j_state_lock); | |
623 | J_ASSERT(journal->j_free > 1); | |
624 | ||
625 | blocknr = journal->j_head; | |
626 | journal->j_head++; | |
627 | journal->j_free--; | |
628 | if (journal->j_head == journal->j_last) | |
629 | journal->j_head = journal->j_first; | |
630 | spin_unlock(&journal->j_state_lock); | |
631 | return journal_bmap(journal, blocknr, retp); | |
632 | } | |
633 | ||
634 | /* | |
635 | * Conversion of logical to physical block numbers for the journal | |
636 | * | |
637 | * On external journals the journal blocks are identity-mapped, so | |
638 | * this is a no-op. If needed, we can use j_blk_offset - everything is | |
639 | * ready. | |
640 | */ | |
9c28cbcc JK |
641 | int journal_bmap(journal_t *journal, unsigned int blocknr, |
642 | unsigned int *retp) | |
1da177e4 LT |
643 | { |
644 | int err = 0; | |
9c28cbcc | 645 | unsigned int ret; |
1da177e4 LT |
646 | |
647 | if (journal->j_inode) { | |
648 | ret = bmap(journal->j_inode, blocknr); | |
649 | if (ret) | |
650 | *retp = ret; | |
651 | else { | |
652 | char b[BDEVNAME_SIZE]; | |
653 | ||
654 | printk(KERN_ALERT "%s: journal block not found " | |
9c28cbcc | 655 | "at offset %u on %s\n", |
08fc99bf | 656 | __func__, |
1da177e4 LT |
657 | blocknr, |
658 | bdevname(journal->j_dev, b)); | |
659 | err = -EIO; | |
660 | __journal_abort_soft(journal, err); | |
661 | } | |
662 | } else { | |
663 | *retp = blocknr; /* +journal->j_blk_offset */ | |
664 | } | |
665 | return err; | |
666 | } | |
667 | ||
668 | /* | |
669 | * We play buffer_head aliasing tricks to write data/metadata blocks to | |
670 | * the journal without copying their contents, but for journal | |
671 | * descriptor blocks we do need to generate bona fide buffers. | |
672 | * | |
673 | * After the caller of journal_get_descriptor_buffer() has finished modifying | |
674 | * the buffer's contents they really should run flush_dcache_page(bh->b_page). | |
675 | * But we don't bother doing that, so there will be coherency problems with | |
676 | * mmaps of blockdevs which hold live JBD-controlled filesystems. | |
677 | */ | |
678 | struct journal_head *journal_get_descriptor_buffer(journal_t *journal) | |
679 | { | |
680 | struct buffer_head *bh; | |
9c28cbcc | 681 | unsigned int blocknr; |
1da177e4 LT |
682 | int err; |
683 | ||
684 | err = journal_next_log_block(journal, &blocknr); | |
685 | ||
686 | if (err) | |
687 | return NULL; | |
688 | ||
689 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
ecca9af0 JK |
690 | if (!bh) |
691 | return NULL; | |
1da177e4 LT |
692 | lock_buffer(bh); |
693 | memset(bh->b_data, 0, journal->j_blocksize); | |
694 | set_buffer_uptodate(bh); | |
695 | unlock_buffer(bh); | |
696 | BUFFER_TRACE(bh, "return this buffer"); | |
697 | return journal_add_journal_head(bh); | |
698 | } | |
699 | ||
700 | /* | |
701 | * Management for journal control blocks: functions to create and | |
702 | * destroy journal_t structures, and to initialise and read existing | |
703 | * journal blocks from disk. */ | |
704 | ||
705 | /* First: create and setup a journal_t object in memory. We initialise | |
706 | * very few fields yet: that has to wait until we have created the | |
707 | * journal structures from from scratch, or loaded them from disk. */ | |
708 | ||
709 | static journal_t * journal_init_common (void) | |
710 | { | |
711 | journal_t *journal; | |
712 | int err; | |
713 | ||
8c3478a5 | 714 | journal = kzalloc(sizeof(*journal), GFP_KERNEL); |
1da177e4 LT |
715 | if (!journal) |
716 | goto fail; | |
1da177e4 LT |
717 | |
718 | init_waitqueue_head(&journal->j_wait_transaction_locked); | |
719 | init_waitqueue_head(&journal->j_wait_logspace); | |
720 | init_waitqueue_head(&journal->j_wait_done_commit); | |
721 | init_waitqueue_head(&journal->j_wait_checkpoint); | |
722 | init_waitqueue_head(&journal->j_wait_commit); | |
723 | init_waitqueue_head(&journal->j_wait_updates); | |
2c68ee75 | 724 | mutex_init(&journal->j_checkpoint_mutex); |
1da177e4 LT |
725 | spin_lock_init(&journal->j_revoke_lock); |
726 | spin_lock_init(&journal->j_list_lock); | |
727 | spin_lock_init(&journal->j_state_lock); | |
728 | ||
729 | journal->j_commit_interval = (HZ * JBD_DEFAULT_MAX_COMMIT_AGE); | |
730 | ||
731 | /* The journal is marked for error until we succeed with recovery! */ | |
732 | journal->j_flags = JFS_ABORT; | |
733 | ||
734 | /* Set up a default-sized revoke table for the new mount. */ | |
735 | err = journal_init_revoke(journal, JOURNAL_REVOKE_DEFAULT_HASH); | |
736 | if (err) { | |
737 | kfree(journal); | |
738 | goto fail; | |
739 | } | |
740 | return journal; | |
741 | fail: | |
742 | return NULL; | |
743 | } | |
744 | ||
745 | /* journal_init_dev and journal_init_inode: | |
746 | * | |
747 | * Create a journal structure assigned some fixed set of disk blocks to | |
748 | * the journal. We don't actually touch those disk blocks yet, but we | |
749 | * need to set up all of the mapping information to tell the journaling | |
750 | * system where the journal blocks are. | |
751 | * | |
752 | */ | |
753 | ||
754 | /** | |
0cf01f66 | 755 | * journal_t * journal_init_dev() - creates and initialises a journal structure |
1da177e4 LT |
756 | * @bdev: Block device on which to create the journal |
757 | * @fs_dev: Device which hold journalled filesystem for this journal. | |
758 | * @start: Block nr Start of journal. | |
37ed3222 | 759 | * @len: Length of the journal in blocks. |
1da177e4 | 760 | * @blocksize: blocksize of journalling device |
0cf01f66 RD |
761 | * |
762 | * Returns: a newly created journal_t * | |
ae6ddcc5 | 763 | * |
1da177e4 LT |
764 | * journal_init_dev creates a journal which maps a fixed contiguous |
765 | * range of blocks on an arbitrary block device. | |
ae6ddcc5 | 766 | * |
1da177e4 LT |
767 | */ |
768 | journal_t * journal_init_dev(struct block_device *bdev, | |
769 | struct block_device *fs_dev, | |
770 | int start, int len, int blocksize) | |
771 | { | |
772 | journal_t *journal = journal_init_common(); | |
773 | struct buffer_head *bh; | |
774 | int n; | |
775 | ||
776 | if (!journal) | |
777 | return NULL; | |
778 | ||
1da177e4 | 779 | /* journal descriptor can store up to n blocks -bzzz */ |
d1807793 | 780 | journal->j_blocksize = blocksize; |
1da177e4 LT |
781 | n = journal->j_blocksize / sizeof(journal_block_tag_t); |
782 | journal->j_wbufsize = n; | |
783 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
784 | if (!journal->j_wbuf) { | |
25985edc | 785 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
08fc99bf | 786 | __func__); |
ecca9af0 | 787 | goto out_err; |
1da177e4 | 788 | } |
d1807793 ZM |
789 | journal->j_dev = bdev; |
790 | journal->j_fs_dev = fs_dev; | |
791 | journal->j_blk_offset = start; | |
792 | journal->j_maxlen = len; | |
793 | ||
794 | bh = __getblk(journal->j_dev, start, journal->j_blocksize); | |
ecca9af0 JK |
795 | if (!bh) { |
796 | printk(KERN_ERR | |
797 | "%s: Cannot get buffer for journal superblock\n", | |
798 | __func__); | |
799 | goto out_err; | |
800 | } | |
d1807793 ZM |
801 | journal->j_sb_buffer = bh; |
802 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
ecca9af0 | 803 | |
1da177e4 | 804 | return journal; |
ecca9af0 | 805 | out_err: |
7b02bec0 | 806 | kfree(journal->j_wbuf); |
ecca9af0 JK |
807 | kfree(journal); |
808 | return NULL; | |
1da177e4 | 809 | } |
ae6ddcc5 MC |
810 | |
811 | /** | |
1da177e4 LT |
812 | * journal_t * journal_init_inode () - creates a journal which maps to a inode. |
813 | * @inode: An inode to create the journal in | |
ae6ddcc5 | 814 | * |
1da177e4 LT |
815 | * journal_init_inode creates a journal which maps an on-disk inode as |
816 | * the journal. The inode must exist already, must support bmap() and | |
817 | * must have all data blocks preallocated. | |
818 | */ | |
819 | journal_t * journal_init_inode (struct inode *inode) | |
820 | { | |
821 | struct buffer_head *bh; | |
822 | journal_t *journal = journal_init_common(); | |
823 | int err; | |
824 | int n; | |
9c28cbcc | 825 | unsigned int blocknr; |
1da177e4 LT |
826 | |
827 | if (!journal) | |
828 | return NULL; | |
829 | ||
830 | journal->j_dev = journal->j_fs_dev = inode->i_sb->s_bdev; | |
831 | journal->j_inode = inode; | |
832 | jbd_debug(1, | |
833 | "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n", | |
ae6ddcc5 | 834 | journal, inode->i_sb->s_id, inode->i_ino, |
1da177e4 LT |
835 | (long long) inode->i_size, |
836 | inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize); | |
837 | ||
838 | journal->j_maxlen = inode->i_size >> inode->i_sb->s_blocksize_bits; | |
839 | journal->j_blocksize = inode->i_sb->s_blocksize; | |
840 | ||
841 | /* journal descriptor can store up to n blocks -bzzz */ | |
842 | n = journal->j_blocksize / sizeof(journal_block_tag_t); | |
843 | journal->j_wbufsize = n; | |
844 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
845 | if (!journal->j_wbuf) { | |
25985edc | 846 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
08fc99bf | 847 | __func__); |
ecca9af0 | 848 | goto out_err; |
1da177e4 LT |
849 | } |
850 | ||
851 | err = journal_bmap(journal, 0, &blocknr); | |
852 | /* If that failed, give up */ | |
853 | if (err) { | |
3c26bdb4 | 854 | printk(KERN_ERR "%s: Cannot locate journal superblock\n", |
08fc99bf | 855 | __func__); |
ecca9af0 | 856 | goto out_err; |
1da177e4 LT |
857 | } |
858 | ||
859 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
ecca9af0 JK |
860 | if (!bh) { |
861 | printk(KERN_ERR | |
862 | "%s: Cannot get buffer for journal superblock\n", | |
863 | __func__); | |
864 | goto out_err; | |
865 | } | |
1da177e4 LT |
866 | journal->j_sb_buffer = bh; |
867 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
868 | ||
869 | return journal; | |
ecca9af0 | 870 | out_err: |
7b02bec0 | 871 | kfree(journal->j_wbuf); |
ecca9af0 JK |
872 | kfree(journal); |
873 | return NULL; | |
1da177e4 LT |
874 | } |
875 | ||
ae6ddcc5 | 876 | /* |
1da177e4 LT |
877 | * If the journal init or create aborts, we need to mark the journal |
878 | * superblock as being NULL to prevent the journal destroy from writing | |
ae6ddcc5 | 879 | * back a bogus superblock. |
1da177e4 LT |
880 | */ |
881 | static void journal_fail_superblock (journal_t *journal) | |
882 | { | |
883 | struct buffer_head *bh = journal->j_sb_buffer; | |
884 | brelse(bh); | |
885 | journal->j_sb_buffer = NULL; | |
886 | } | |
887 | ||
888 | /* | |
889 | * Given a journal_t structure, initialise the various fields for | |
890 | * startup of a new journaling session. We use this both when creating | |
891 | * a journal, and after recovering an old journal to reset it for | |
892 | * subsequent use. | |
893 | */ | |
894 | ||
895 | static int journal_reset(journal_t *journal) | |
896 | { | |
897 | journal_superblock_t *sb = journal->j_superblock; | |
9c28cbcc | 898 | unsigned int first, last; |
1da177e4 LT |
899 | |
900 | first = be32_to_cpu(sb->s_first); | |
901 | last = be32_to_cpu(sb->s_maxlen); | |
7447a668 | 902 | if (first + JFS_MIN_JOURNAL_BLOCKS > last + 1) { |
9c28cbcc | 903 | printk(KERN_ERR "JBD: Journal too short (blocks %u-%u).\n", |
7447a668 JK |
904 | first, last); |
905 | journal_fail_superblock(journal); | |
906 | return -EINVAL; | |
907 | } | |
1da177e4 LT |
908 | |
909 | journal->j_first = first; | |
910 | journal->j_last = last; | |
911 | ||
912 | journal->j_head = first; | |
913 | journal->j_tail = first; | |
914 | journal->j_free = last - first; | |
915 | ||
916 | journal->j_tail_sequence = journal->j_transaction_sequence; | |
917 | journal->j_commit_sequence = journal->j_transaction_sequence - 1; | |
918 | journal->j_commit_request = journal->j_commit_sequence; | |
919 | ||
920 | journal->j_max_transaction_buffers = journal->j_maxlen / 4; | |
921 | ||
922 | /* Add the dynamic fields and write it to disk. */ | |
923 | journal_update_superblock(journal, 1); | |
97f06784 | 924 | return journal_start_thread(journal); |
1da177e4 LT |
925 | } |
926 | ||
ae6ddcc5 | 927 | /** |
1da177e4 LT |
928 | * int journal_create() - Initialise the new journal file |
929 | * @journal: Journal to create. This structure must have been initialised | |
ae6ddcc5 | 930 | * |
1da177e4 LT |
931 | * Given a journal_t structure which tells us which disk blocks we can |
932 | * use, create a new journal superblock and initialise all of the | |
ae6ddcc5 | 933 | * journal fields from scratch. |
1da177e4 LT |
934 | **/ |
935 | int journal_create(journal_t *journal) | |
936 | { | |
9c28cbcc | 937 | unsigned int blocknr; |
1da177e4 LT |
938 | struct buffer_head *bh; |
939 | journal_superblock_t *sb; | |
940 | int i, err; | |
941 | ||
942 | if (journal->j_maxlen < JFS_MIN_JOURNAL_BLOCKS) { | |
943 | printk (KERN_ERR "Journal length (%d blocks) too short.\n", | |
944 | journal->j_maxlen); | |
945 | journal_fail_superblock(journal); | |
946 | return -EINVAL; | |
947 | } | |
948 | ||
949 | if (journal->j_inode == NULL) { | |
950 | /* | |
951 | * We don't know what block to start at! | |
952 | */ | |
953 | printk(KERN_EMERG | |
954 | "%s: creation of journal on external device!\n", | |
08fc99bf | 955 | __func__); |
1da177e4 LT |
956 | BUG(); |
957 | } | |
958 | ||
959 | /* Zero out the entire journal on disk. We cannot afford to | |
960 | have any blocks on disk beginning with JFS_MAGIC_NUMBER. */ | |
961 | jbd_debug(1, "JBD: Zeroing out journal blocks...\n"); | |
962 | for (i = 0; i < journal->j_maxlen; i++) { | |
963 | err = journal_bmap(journal, i, &blocknr); | |
964 | if (err) | |
965 | return err; | |
966 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
2a0e3388 NK |
967 | if (unlikely(!bh)) |
968 | return -ENOMEM; | |
1da177e4 LT |
969 | lock_buffer(bh); |
970 | memset (bh->b_data, 0, journal->j_blocksize); | |
971 | BUFFER_TRACE(bh, "marking dirty"); | |
972 | mark_buffer_dirty(bh); | |
973 | BUFFER_TRACE(bh, "marking uptodate"); | |
974 | set_buffer_uptodate(bh); | |
975 | unlock_buffer(bh); | |
976 | __brelse(bh); | |
977 | } | |
978 | ||
979 | sync_blockdev(journal->j_dev); | |
980 | jbd_debug(1, "JBD: journal cleared.\n"); | |
981 | ||
982 | /* OK, fill in the initial static fields in the new superblock */ | |
983 | sb = journal->j_superblock; | |
984 | ||
985 | sb->s_header.h_magic = cpu_to_be32(JFS_MAGIC_NUMBER); | |
986 | sb->s_header.h_blocktype = cpu_to_be32(JFS_SUPERBLOCK_V2); | |
987 | ||
988 | sb->s_blocksize = cpu_to_be32(journal->j_blocksize); | |
989 | sb->s_maxlen = cpu_to_be32(journal->j_maxlen); | |
990 | sb->s_first = cpu_to_be32(1); | |
991 | ||
992 | journal->j_transaction_sequence = 1; | |
993 | ||
994 | journal->j_flags &= ~JFS_ABORT; | |
995 | journal->j_format_version = 2; | |
996 | ||
997 | return journal_reset(journal); | |
998 | } | |
999 | ||
ae6ddcc5 | 1000 | /** |
1da177e4 LT |
1001 | * void journal_update_superblock() - Update journal sb on disk. |
1002 | * @journal: The journal to update. | |
1003 | * @wait: Set to '0' if you don't want to wait for IO completion. | |
1004 | * | |
1005 | * Update a journal's dynamic superblock fields and write it to disk, | |
1006 | * optionally waiting for the IO to complete. | |
1007 | */ | |
1008 | void journal_update_superblock(journal_t *journal, int wait) | |
1009 | { | |
1010 | journal_superblock_t *sb = journal->j_superblock; | |
1011 | struct buffer_head *bh = journal->j_sb_buffer; | |
1012 | ||
1013 | /* | |
1014 | * As a special case, if the on-disk copy is already marked as needing | |
1015 | * no recovery (s_start == 0) and there are no outstanding transactions | |
1016 | * in the filesystem, then we can safely defer the superblock update | |
1017 | * until the next commit by setting JFS_FLUSHED. This avoids | |
1018 | * attempting a write to a potential-readonly device. | |
1019 | */ | |
1020 | if (sb->s_start == 0 && journal->j_tail_sequence == | |
1021 | journal->j_transaction_sequence) { | |
1022 | jbd_debug(1,"JBD: Skipping superblock update on recovered sb " | |
9c28cbcc | 1023 | "(start %u, seq %d, errno %d)\n", |
ae6ddcc5 | 1024 | journal->j_tail, journal->j_tail_sequence, |
1da177e4 LT |
1025 | journal->j_errno); |
1026 | goto out; | |
1027 | } | |
1028 | ||
dff6825e DW |
1029 | if (buffer_write_io_error(bh)) { |
1030 | char b[BDEVNAME_SIZE]; | |
1031 | /* | |
1032 | * Oh, dear. A previous attempt to write the journal | |
1033 | * superblock failed. This could happen because the | |
1034 | * USB device was yanked out. Or it could happen to | |
1035 | * be a transient write error and maybe the block will | |
1036 | * be remapped. Nothing we can do but to retry the | |
1037 | * write and hope for the best. | |
1038 | */ | |
1039 | printk(KERN_ERR "JBD: previous I/O error detected " | |
1040 | "for journal superblock update for %s.\n", | |
1041 | journal_dev_name(journal, b)); | |
1042 | clear_buffer_write_io_error(bh); | |
1043 | set_buffer_uptodate(bh); | |
1044 | } | |
1045 | ||
1da177e4 | 1046 | spin_lock(&journal->j_state_lock); |
9c28cbcc | 1047 | jbd_debug(1,"JBD: updating superblock (start %u, seq %d, errno %d)\n", |
1da177e4 LT |
1048 | journal->j_tail, journal->j_tail_sequence, journal->j_errno); |
1049 | ||
1050 | sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); | |
1051 | sb->s_start = cpu_to_be32(journal->j_tail); | |
1052 | sb->s_errno = cpu_to_be32(journal->j_errno); | |
1053 | spin_unlock(&journal->j_state_lock); | |
1054 | ||
1055 | BUFFER_TRACE(bh, "marking dirty"); | |
1056 | mark_buffer_dirty(bh); | |
dff6825e | 1057 | if (wait) { |
1da177e4 | 1058 | sync_dirty_buffer(bh); |
dff6825e DW |
1059 | if (buffer_write_io_error(bh)) { |
1060 | char b[BDEVNAME_SIZE]; | |
1061 | printk(KERN_ERR "JBD: I/O error detected " | |
1062 | "when updating journal superblock for %s.\n", | |
1063 | journal_dev_name(journal, b)); | |
1064 | clear_buffer_write_io_error(bh); | |
1065 | set_buffer_uptodate(bh); | |
1066 | } | |
1067 | } else | |
9cb569d6 | 1068 | write_dirty_buffer(bh, WRITE); |
1da177e4 | 1069 | |
99cb1a31 | 1070 | trace_jbd_update_superblock_end(journal, wait); |
1da177e4 LT |
1071 | out: |
1072 | /* If we have just flushed the log (by marking s_start==0), then | |
1073 | * any future commit will have to be careful to update the | |
1074 | * superblock again to re-record the true start of the log. */ | |
1075 | ||
1076 | spin_lock(&journal->j_state_lock); | |
1077 | if (sb->s_start) | |
1078 | journal->j_flags &= ~JFS_FLUSHED; | |
1079 | else | |
1080 | journal->j_flags |= JFS_FLUSHED; | |
1081 | spin_unlock(&journal->j_state_lock); | |
1082 | } | |
1083 | ||
1084 | /* | |
1085 | * Read the superblock for a given journal, performing initial | |
1086 | * validation of the format. | |
1087 | */ | |
1088 | ||
1089 | static int journal_get_superblock(journal_t *journal) | |
1090 | { | |
1091 | struct buffer_head *bh; | |
1092 | journal_superblock_t *sb; | |
1093 | int err = -EIO; | |
1094 | ||
1095 | bh = journal->j_sb_buffer; | |
1096 | ||
1097 | J_ASSERT(bh != NULL); | |
1098 | if (!buffer_uptodate(bh)) { | |
1099 | ll_rw_block(READ, 1, &bh); | |
1100 | wait_on_buffer(bh); | |
1101 | if (!buffer_uptodate(bh)) { | |
1102 | printk (KERN_ERR | |
1103 | "JBD: IO error reading journal superblock\n"); | |
1104 | goto out; | |
1105 | } | |
1106 | } | |
1107 | ||
1108 | sb = journal->j_superblock; | |
1109 | ||
1110 | err = -EINVAL; | |
1111 | ||
1112 | if (sb->s_header.h_magic != cpu_to_be32(JFS_MAGIC_NUMBER) || | |
1113 | sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) { | |
1114 | printk(KERN_WARNING "JBD: no valid journal superblock found\n"); | |
1115 | goto out; | |
1116 | } | |
1117 | ||
1118 | switch(be32_to_cpu(sb->s_header.h_blocktype)) { | |
1119 | case JFS_SUPERBLOCK_V1: | |
1120 | journal->j_format_version = 1; | |
1121 | break; | |
1122 | case JFS_SUPERBLOCK_V2: | |
1123 | journal->j_format_version = 2; | |
1124 | break; | |
1125 | default: | |
1126 | printk(KERN_WARNING "JBD: unrecognised superblock format ID\n"); | |
1127 | goto out; | |
1128 | } | |
1129 | ||
1130 | if (be32_to_cpu(sb->s_maxlen) < journal->j_maxlen) | |
1131 | journal->j_maxlen = be32_to_cpu(sb->s_maxlen); | |
1132 | else if (be32_to_cpu(sb->s_maxlen) > journal->j_maxlen) { | |
1133 | printk (KERN_WARNING "JBD: journal file too short\n"); | |
1134 | goto out; | |
1135 | } | |
1136 | ||
8762202d EG |
1137 | if (be32_to_cpu(sb->s_first) == 0 || |
1138 | be32_to_cpu(sb->s_first) >= journal->j_maxlen) { | |
1139 | printk(KERN_WARNING | |
1140 | "JBD: Invalid start block of journal: %u\n", | |
1141 | be32_to_cpu(sb->s_first)); | |
1142 | goto out; | |
1143 | } | |
1144 | ||
1da177e4 LT |
1145 | return 0; |
1146 | ||
1147 | out: | |
1148 | journal_fail_superblock(journal); | |
1149 | return err; | |
1150 | } | |
1151 | ||
1152 | /* | |
1153 | * Load the on-disk journal superblock and read the key fields into the | |
1154 | * journal_t. | |
1155 | */ | |
1156 | ||
1157 | static int load_superblock(journal_t *journal) | |
1158 | { | |
1159 | int err; | |
1160 | journal_superblock_t *sb; | |
1161 | ||
1162 | err = journal_get_superblock(journal); | |
1163 | if (err) | |
1164 | return err; | |
1165 | ||
1166 | sb = journal->j_superblock; | |
1167 | ||
1168 | journal->j_tail_sequence = be32_to_cpu(sb->s_sequence); | |
1169 | journal->j_tail = be32_to_cpu(sb->s_start); | |
1170 | journal->j_first = be32_to_cpu(sb->s_first); | |
1171 | journal->j_last = be32_to_cpu(sb->s_maxlen); | |
1172 | journal->j_errno = be32_to_cpu(sb->s_errno); | |
1173 | ||
1174 | return 0; | |
1175 | } | |
1176 | ||
1177 | ||
1178 | /** | |
1179 | * int journal_load() - Read journal from disk. | |
1180 | * @journal: Journal to act on. | |
ae6ddcc5 | 1181 | * |
1da177e4 LT |
1182 | * Given a journal_t structure which tells us which disk blocks contain |
1183 | * a journal, read the journal from disk to initialise the in-memory | |
1184 | * structures. | |
1185 | */ | |
1186 | int journal_load(journal_t *journal) | |
1187 | { | |
1188 | int err; | |
ea817398 | 1189 | journal_superblock_t *sb; |
1da177e4 LT |
1190 | |
1191 | err = load_superblock(journal); | |
1192 | if (err) | |
1193 | return err; | |
1194 | ||
ea817398 | 1195 | sb = journal->j_superblock; |
1da177e4 LT |
1196 | /* If this is a V2 superblock, then we have to check the |
1197 | * features flags on it. */ | |
1198 | ||
1199 | if (journal->j_format_version >= 2) { | |
1da177e4 LT |
1200 | if ((sb->s_feature_ro_compat & |
1201 | ~cpu_to_be32(JFS_KNOWN_ROCOMPAT_FEATURES)) || | |
1202 | (sb->s_feature_incompat & | |
1203 | ~cpu_to_be32(JFS_KNOWN_INCOMPAT_FEATURES))) { | |
1204 | printk (KERN_WARNING | |
1205 | "JBD: Unrecognised features on journal\n"); | |
1206 | return -EINVAL; | |
1207 | } | |
1208 | } | |
1209 | ||
1210 | /* Let the recovery code check whether it needs to recover any | |
1211 | * data from the journal. */ | |
1212 | if (journal_recover(journal)) | |
1213 | goto recovery_error; | |
1214 | ||
1215 | /* OK, we've finished with the dynamic journal bits: | |
1216 | * reinitialise the dynamic contents of the superblock in memory | |
1217 | * and reset them on disk. */ | |
1218 | if (journal_reset(journal)) | |
1219 | goto recovery_error; | |
1220 | ||
1221 | journal->j_flags &= ~JFS_ABORT; | |
1222 | journal->j_flags |= JFS_LOADED; | |
1223 | return 0; | |
1224 | ||
1225 | recovery_error: | |
1226 | printk (KERN_WARNING "JBD: recovery failed\n"); | |
1227 | return -EIO; | |
1228 | } | |
1229 | ||
1230 | /** | |
1231 | * void journal_destroy() - Release a journal_t structure. | |
1232 | * @journal: Journal to act on. | |
1233 | * | |
1234 | * Release a journal_t structure once it is no longer in use by the | |
1235 | * journaled object. | |
4afe9785 | 1236 | * Return <0 if we couldn't clean up the journal. |
1da177e4 | 1237 | */ |
4afe9785 | 1238 | int journal_destroy(journal_t *journal) |
1da177e4 | 1239 | { |
4afe9785 HK |
1240 | int err = 0; |
1241 | ||
03f4d804 | 1242 | |
1da177e4 LT |
1243 | /* Wait for the commit thread to wake up and die. */ |
1244 | journal_kill_thread(journal); | |
1245 | ||
1246 | /* Force a final log commit */ | |
1247 | if (journal->j_running_transaction) | |
1248 | journal_commit_transaction(journal); | |
1249 | ||
1250 | /* Force any old transactions to disk */ | |
1251 | ||
1252 | /* Totally anal locking here... */ | |
1253 | spin_lock(&journal->j_list_lock); | |
1254 | while (journal->j_checkpoint_transactions != NULL) { | |
1255 | spin_unlock(&journal->j_list_lock); | |
1256 | log_do_checkpoint(journal); | |
1257 | spin_lock(&journal->j_list_lock); | |
1258 | } | |
1259 | ||
1260 | J_ASSERT(journal->j_running_transaction == NULL); | |
1261 | J_ASSERT(journal->j_committing_transaction == NULL); | |
1262 | J_ASSERT(journal->j_checkpoint_transactions == NULL); | |
1263 | spin_unlock(&journal->j_list_lock); | |
1264 | ||
1da177e4 | 1265 | if (journal->j_sb_buffer) { |
4afe9785 HK |
1266 | if (!is_journal_aborted(journal)) { |
1267 | /* We can now mark the journal as empty. */ | |
1268 | journal->j_tail = 0; | |
1269 | journal->j_tail_sequence = | |
1270 | ++journal->j_transaction_sequence; | |
1271 | journal_update_superblock(journal, 1); | |
1272 | } else { | |
1273 | err = -EIO; | |
1274 | } | |
1da177e4 LT |
1275 | brelse(journal->j_sb_buffer); |
1276 | } | |
1277 | ||
1278 | if (journal->j_inode) | |
1279 | iput(journal->j_inode); | |
1280 | if (journal->j_revoke) | |
1281 | journal_destroy_revoke(journal); | |
1282 | kfree(journal->j_wbuf); | |
1283 | kfree(journal); | |
4afe9785 HK |
1284 | |
1285 | return err; | |
1da177e4 LT |
1286 | } |
1287 | ||
1288 | ||
1289 | /** | |
1290 | *int journal_check_used_features () - Check if features specified are used. | |
1291 | * @journal: Journal to check. | |
1292 | * @compat: bitmask of compatible features | |
1293 | * @ro: bitmask of features that force read-only mount | |
1294 | * @incompat: bitmask of incompatible features | |
ae6ddcc5 | 1295 | * |
1da177e4 | 1296 | * Check whether the journal uses all of a given set of |
ae6ddcc5 | 1297 | * features. Return true (non-zero) if it does. |
1da177e4 LT |
1298 | **/ |
1299 | ||
1300 | int journal_check_used_features (journal_t *journal, unsigned long compat, | |
1301 | unsigned long ro, unsigned long incompat) | |
1302 | { | |
1303 | journal_superblock_t *sb; | |
1304 | ||
1305 | if (!compat && !ro && !incompat) | |
1306 | return 1; | |
1307 | if (journal->j_format_version == 1) | |
1308 | return 0; | |
1309 | ||
1310 | sb = journal->j_superblock; | |
1311 | ||
1312 | if (((be32_to_cpu(sb->s_feature_compat) & compat) == compat) && | |
1313 | ((be32_to_cpu(sb->s_feature_ro_compat) & ro) == ro) && | |
1314 | ((be32_to_cpu(sb->s_feature_incompat) & incompat) == incompat)) | |
1315 | return 1; | |
1316 | ||
1317 | return 0; | |
1318 | } | |
1319 | ||
1320 | /** | |
1321 | * int journal_check_available_features() - Check feature set in journalling layer | |
1322 | * @journal: Journal to check. | |
1323 | * @compat: bitmask of compatible features | |
1324 | * @ro: bitmask of features that force read-only mount | |
1325 | * @incompat: bitmask of incompatible features | |
ae6ddcc5 | 1326 | * |
1da177e4 LT |
1327 | * Check whether the journaling code supports the use of |
1328 | * all of a given set of features on this journal. Return true | |
1329 | * (non-zero) if it can. */ | |
1330 | ||
1331 | int journal_check_available_features (journal_t *journal, unsigned long compat, | |
1332 | unsigned long ro, unsigned long incompat) | |
1333 | { | |
1da177e4 LT |
1334 | if (!compat && !ro && !incompat) |
1335 | return 1; | |
1336 | ||
1da177e4 LT |
1337 | /* We can support any known requested features iff the |
1338 | * superblock is in version 2. Otherwise we fail to support any | |
1339 | * extended sb features. */ | |
1340 | ||
1341 | if (journal->j_format_version != 2) | |
1342 | return 0; | |
1343 | ||
1344 | if ((compat & JFS_KNOWN_COMPAT_FEATURES) == compat && | |
1345 | (ro & JFS_KNOWN_ROCOMPAT_FEATURES) == ro && | |
1346 | (incompat & JFS_KNOWN_INCOMPAT_FEATURES) == incompat) | |
1347 | return 1; | |
1348 | ||
1349 | return 0; | |
1350 | } | |
1351 | ||
1352 | /** | |
1353 | * int journal_set_features () - Mark a given journal feature in the superblock | |
1354 | * @journal: Journal to act on. | |
1355 | * @compat: bitmask of compatible features | |
1356 | * @ro: bitmask of features that force read-only mount | |
1357 | * @incompat: bitmask of incompatible features | |
1358 | * | |
1359 | * Mark a given journal feature as present on the | |
ae6ddcc5 | 1360 | * superblock. Returns true if the requested features could be set. |
1da177e4 LT |
1361 | * |
1362 | */ | |
1363 | ||
1364 | int journal_set_features (journal_t *journal, unsigned long compat, | |
1365 | unsigned long ro, unsigned long incompat) | |
1366 | { | |
1367 | journal_superblock_t *sb; | |
1368 | ||
1369 | if (journal_check_used_features(journal, compat, ro, incompat)) | |
1370 | return 1; | |
1371 | ||
1372 | if (!journal_check_available_features(journal, compat, ro, incompat)) | |
1373 | return 0; | |
1374 | ||
1375 | jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n", | |
1376 | compat, ro, incompat); | |
1377 | ||
1378 | sb = journal->j_superblock; | |
1379 | ||
1380 | sb->s_feature_compat |= cpu_to_be32(compat); | |
1381 | sb->s_feature_ro_compat |= cpu_to_be32(ro); | |
1382 | sb->s_feature_incompat |= cpu_to_be32(incompat); | |
1383 | ||
1384 | return 1; | |
1385 | } | |
1386 | ||
1387 | ||
1388 | /** | |
1389 | * int journal_update_format () - Update on-disk journal structure. | |
1390 | * @journal: Journal to act on. | |
1391 | * | |
1392 | * Given an initialised but unloaded journal struct, poke about in the | |
1393 | * on-disk structure to update it to the most recent supported version. | |
1394 | */ | |
1395 | int journal_update_format (journal_t *journal) | |
1396 | { | |
1397 | journal_superblock_t *sb; | |
1398 | int err; | |
1399 | ||
1400 | err = journal_get_superblock(journal); | |
1401 | if (err) | |
1402 | return err; | |
1403 | ||
1404 | sb = journal->j_superblock; | |
1405 | ||
1406 | switch (be32_to_cpu(sb->s_header.h_blocktype)) { | |
1407 | case JFS_SUPERBLOCK_V2: | |
1408 | return 0; | |
1409 | case JFS_SUPERBLOCK_V1: | |
1410 | return journal_convert_superblock_v1(journal, sb); | |
1411 | default: | |
1412 | break; | |
1413 | } | |
1414 | return -EINVAL; | |
1415 | } | |
1416 | ||
1417 | static int journal_convert_superblock_v1(journal_t *journal, | |
1418 | journal_superblock_t *sb) | |
1419 | { | |
1420 | int offset, blocksize; | |
1421 | struct buffer_head *bh; | |
1422 | ||
1423 | printk(KERN_WARNING | |
1424 | "JBD: Converting superblock from version 1 to 2.\n"); | |
1425 | ||
1426 | /* Pre-initialise new fields to zero */ | |
1427 | offset = ((char *) &(sb->s_feature_compat)) - ((char *) sb); | |
1428 | blocksize = be32_to_cpu(sb->s_blocksize); | |
1429 | memset(&sb->s_feature_compat, 0, blocksize-offset); | |
1430 | ||
1431 | sb->s_nr_users = cpu_to_be32(1); | |
1432 | sb->s_header.h_blocktype = cpu_to_be32(JFS_SUPERBLOCK_V2); | |
1433 | journal->j_format_version = 2; | |
1434 | ||
1435 | bh = journal->j_sb_buffer; | |
1436 | BUFFER_TRACE(bh, "marking dirty"); | |
1437 | mark_buffer_dirty(bh); | |
1438 | sync_dirty_buffer(bh); | |
1439 | return 0; | |
1440 | } | |
1441 | ||
1442 | ||
1443 | /** | |
1444 | * int journal_flush () - Flush journal | |
1445 | * @journal: Journal to act on. | |
ae6ddcc5 | 1446 | * |
1da177e4 LT |
1447 | * Flush all data for a given journal to disk and empty the journal. |
1448 | * Filesystems can use this when remounting readonly to ensure that | |
1449 | * recovery does not need to happen on remount. | |
1450 | */ | |
1451 | ||
1452 | int journal_flush(journal_t *journal) | |
1453 | { | |
1454 | int err = 0; | |
1455 | transaction_t *transaction = NULL; | |
9c28cbcc | 1456 | unsigned int old_tail; |
1da177e4 LT |
1457 | |
1458 | spin_lock(&journal->j_state_lock); | |
1459 | ||
1460 | /* Force everything buffered to the log... */ | |
1461 | if (journal->j_running_transaction) { | |
1462 | transaction = journal->j_running_transaction; | |
1463 | __log_start_commit(journal, transaction->t_tid); | |
1464 | } else if (journal->j_committing_transaction) | |
1465 | transaction = journal->j_committing_transaction; | |
1466 | ||
1467 | /* Wait for the log commit to complete... */ | |
1468 | if (transaction) { | |
1469 | tid_t tid = transaction->t_tid; | |
1470 | ||
1471 | spin_unlock(&journal->j_state_lock); | |
1472 | log_wait_commit(journal, tid); | |
1473 | } else { | |
1474 | spin_unlock(&journal->j_state_lock); | |
1475 | } | |
1476 | ||
1477 | /* ...and flush everything in the log out to disk. */ | |
1478 | spin_lock(&journal->j_list_lock); | |
1479 | while (!err && journal->j_checkpoint_transactions != NULL) { | |
1480 | spin_unlock(&journal->j_list_lock); | |
4afe9785 | 1481 | mutex_lock(&journal->j_checkpoint_mutex); |
1da177e4 | 1482 | err = log_do_checkpoint(journal); |
4afe9785 | 1483 | mutex_unlock(&journal->j_checkpoint_mutex); |
1da177e4 LT |
1484 | spin_lock(&journal->j_list_lock); |
1485 | } | |
1486 | spin_unlock(&journal->j_list_lock); | |
4afe9785 HK |
1487 | |
1488 | if (is_journal_aborted(journal)) | |
1489 | return -EIO; | |
1490 | ||
1da177e4 LT |
1491 | cleanup_journal_tail(journal); |
1492 | ||
1493 | /* Finally, mark the journal as really needing no recovery. | |
1494 | * This sets s_start==0 in the underlying superblock, which is | |
1495 | * the magic code for a fully-recovered superblock. Any future | |
1496 | * commits of data to the journal will restore the current | |
1497 | * s_start value. */ | |
1498 | spin_lock(&journal->j_state_lock); | |
1499 | old_tail = journal->j_tail; | |
1500 | journal->j_tail = 0; | |
1501 | spin_unlock(&journal->j_state_lock); | |
1502 | journal_update_superblock(journal, 1); | |
1503 | spin_lock(&journal->j_state_lock); | |
1504 | journal->j_tail = old_tail; | |
1505 | ||
1506 | J_ASSERT(!journal->j_running_transaction); | |
1507 | J_ASSERT(!journal->j_committing_transaction); | |
1508 | J_ASSERT(!journal->j_checkpoint_transactions); | |
1509 | J_ASSERT(journal->j_head == journal->j_tail); | |
1510 | J_ASSERT(journal->j_tail_sequence == journal->j_transaction_sequence); | |
1511 | spin_unlock(&journal->j_state_lock); | |
4afe9785 | 1512 | return 0; |
1da177e4 LT |
1513 | } |
1514 | ||
1515 | /** | |
1516 | * int journal_wipe() - Wipe journal contents | |
1517 | * @journal: Journal to act on. | |
1518 | * @write: flag (see below) | |
ae6ddcc5 | 1519 | * |
1da177e4 LT |
1520 | * Wipe out all of the contents of a journal, safely. This will produce |
1521 | * a warning if the journal contains any valid recovery information. | |
1522 | * Must be called between journal_init_*() and journal_load(). | |
1523 | * | |
1524 | * If 'write' is non-zero, then we wipe out the journal on disk; otherwise | |
1525 | * we merely suppress recovery. | |
1526 | */ | |
1527 | ||
1528 | int journal_wipe(journal_t *journal, int write) | |
1529 | { | |
1da177e4 LT |
1530 | int err = 0; |
1531 | ||
1532 | J_ASSERT (!(journal->j_flags & JFS_LOADED)); | |
1533 | ||
1534 | err = load_superblock(journal); | |
1535 | if (err) | |
1536 | return err; | |
1537 | ||
1da177e4 LT |
1538 | if (!journal->j_tail) |
1539 | goto no_recovery; | |
1540 | ||
1541 | printk (KERN_WARNING "JBD: %s recovery information on journal\n", | |
1542 | write ? "Clearing" : "Ignoring"); | |
1543 | ||
1544 | err = journal_skip_recovery(journal); | |
1545 | if (write) | |
1546 | journal_update_superblock(journal, 1); | |
1547 | ||
1548 | no_recovery: | |
1549 | return err; | |
1550 | } | |
1551 | ||
1552 | /* | |
1553 | * journal_dev_name: format a character string to describe on what | |
1554 | * device this journal is present. | |
1555 | */ | |
1556 | ||
022a4a7b | 1557 | static const char *journal_dev_name(journal_t *journal, char *buffer) |
1da177e4 LT |
1558 | { |
1559 | struct block_device *bdev; | |
1560 | ||
1561 | if (journal->j_inode) | |
1562 | bdev = journal->j_inode->i_sb->s_bdev; | |
1563 | else | |
1564 | bdev = journal->j_dev; | |
1565 | ||
1566 | return bdevname(bdev, buffer); | |
1567 | } | |
1568 | ||
1569 | /* | |
1570 | * Journal abort has very specific semantics, which we describe | |
ae6ddcc5 | 1571 | * for journal abort. |
1da177e4 LT |
1572 | * |
1573 | * Two internal function, which provide abort to te jbd layer | |
1574 | * itself are here. | |
1575 | */ | |
1576 | ||
1577 | /* | |
1578 | * Quick version for internal journal use (doesn't lock the journal). | |
1579 | * Aborts hard --- we mark the abort as occurred, but do _nothing_ else, | |
1580 | * and don't attempt to make any other journal updates. | |
1581 | */ | |
53308383 | 1582 | static void __journal_abort_hard(journal_t *journal) |
1da177e4 LT |
1583 | { |
1584 | transaction_t *transaction; | |
1585 | char b[BDEVNAME_SIZE]; | |
1586 | ||
1587 | if (journal->j_flags & JFS_ABORT) | |
1588 | return; | |
1589 | ||
1590 | printk(KERN_ERR "Aborting journal on device %s.\n", | |
1591 | journal_dev_name(journal, b)); | |
1592 | ||
1593 | spin_lock(&journal->j_state_lock); | |
1594 | journal->j_flags |= JFS_ABORT; | |
1595 | transaction = journal->j_running_transaction; | |
1596 | if (transaction) | |
1597 | __log_start_commit(journal, transaction->t_tid); | |
1598 | spin_unlock(&journal->j_state_lock); | |
1599 | } | |
1600 | ||
1601 | /* Soft abort: record the abort error status in the journal superblock, | |
1602 | * but don't do any other IO. */ | |
022a4a7b | 1603 | static void __journal_abort_soft (journal_t *journal, int errno) |
1da177e4 LT |
1604 | { |
1605 | if (journal->j_flags & JFS_ABORT) | |
1606 | return; | |
1607 | ||
1608 | if (!journal->j_errno) | |
1609 | journal->j_errno = errno; | |
1610 | ||
1611 | __journal_abort_hard(journal); | |
1612 | ||
1613 | if (errno) | |
1614 | journal_update_superblock(journal, 1); | |
1615 | } | |
1616 | ||
1617 | /** | |
1618 | * void journal_abort () - Shutdown the journal immediately. | |
1619 | * @journal: the journal to shutdown. | |
1620 | * @errno: an error number to record in the journal indicating | |
1621 | * the reason for the shutdown. | |
1622 | * | |
1623 | * Perform a complete, immediate shutdown of the ENTIRE | |
1624 | * journal (not of a single transaction). This operation cannot be | |
1625 | * undone without closing and reopening the journal. | |
ae6ddcc5 | 1626 | * |
1da177e4 LT |
1627 | * The journal_abort function is intended to support higher level error |
1628 | * recovery mechanisms such as the ext2/ext3 remount-readonly error | |
1629 | * mode. | |
1630 | * | |
1631 | * Journal abort has very specific semantics. Any existing dirty, | |
1632 | * unjournaled buffers in the main filesystem will still be written to | |
1633 | * disk by bdflush, but the journaling mechanism will be suspended | |
1634 | * immediately and no further transaction commits will be honoured. | |
1635 | * | |
1636 | * Any dirty, journaled buffers will be written back to disk without | |
1637 | * hitting the journal. Atomicity cannot be guaranteed on an aborted | |
1638 | * filesystem, but we _do_ attempt to leave as much data as possible | |
1639 | * behind for fsck to use for cleanup. | |
1640 | * | |
1641 | * Any attempt to get a new transaction handle on a journal which is in | |
1642 | * ABORT state will just result in an -EROFS error return. A | |
1643 | * journal_stop on an existing handle will return -EIO if we have | |
1644 | * entered abort state during the update. | |
1645 | * | |
1646 | * Recursive transactions are not disturbed by journal abort until the | |
1647 | * final journal_stop, which will receive the -EIO error. | |
1648 | * | |
1649 | * Finally, the journal_abort call allows the caller to supply an errno | |
1650 | * which will be recorded (if possible) in the journal superblock. This | |
1651 | * allows a client to record failure conditions in the middle of a | |
1652 | * transaction without having to complete the transaction to record the | |
1653 | * failure to disk. ext3_error, for example, now uses this | |
1654 | * functionality. | |
1655 | * | |
1656 | * Errors which originate from within the journaling layer will NOT | |
1657 | * supply an errno; a null errno implies that absolutely no further | |
1658 | * writes are done to the journal (unless there are any already in | |
1659 | * progress). | |
ae6ddcc5 | 1660 | * |
1da177e4 LT |
1661 | */ |
1662 | ||
1663 | void journal_abort(journal_t *journal, int errno) | |
1664 | { | |
1665 | __journal_abort_soft(journal, errno); | |
1666 | } | |
1667 | ||
ae6ddcc5 | 1668 | /** |
1da177e4 LT |
1669 | * int journal_errno () - returns the journal's error state. |
1670 | * @journal: journal to examine. | |
1671 | * | |
1672 | * This is the errno numbet set with journal_abort(), the last | |
1673 | * time the journal was mounted - if the journal was stopped | |
1674 | * without calling abort this will be 0. | |
1675 | * | |
1676 | * If the journal has been aborted on this mount time -EROFS will | |
1677 | * be returned. | |
1678 | */ | |
1679 | int journal_errno(journal_t *journal) | |
1680 | { | |
1681 | int err; | |
1682 | ||
1683 | spin_lock(&journal->j_state_lock); | |
1684 | if (journal->j_flags & JFS_ABORT) | |
1685 | err = -EROFS; | |
1686 | else | |
1687 | err = journal->j_errno; | |
1688 | spin_unlock(&journal->j_state_lock); | |
1689 | return err; | |
1690 | } | |
1691 | ||
ae6ddcc5 | 1692 | /** |
1da177e4 LT |
1693 | * int journal_clear_err () - clears the journal's error state |
1694 | * @journal: journal to act on. | |
1695 | * | |
1696 | * An error must be cleared or Acked to take a FS out of readonly | |
1697 | * mode. | |
1698 | */ | |
1699 | int journal_clear_err(journal_t *journal) | |
1700 | { | |
1701 | int err = 0; | |
1702 | ||
1703 | spin_lock(&journal->j_state_lock); | |
1704 | if (journal->j_flags & JFS_ABORT) | |
1705 | err = -EROFS; | |
1706 | else | |
1707 | journal->j_errno = 0; | |
1708 | spin_unlock(&journal->j_state_lock); | |
1709 | return err; | |
1710 | } | |
1711 | ||
ae6ddcc5 | 1712 | /** |
1da177e4 LT |
1713 | * void journal_ack_err() - Ack journal err. |
1714 | * @journal: journal to act on. | |
1715 | * | |
1716 | * An error must be cleared or Acked to take a FS out of readonly | |
1717 | * mode. | |
1718 | */ | |
1719 | void journal_ack_err(journal_t *journal) | |
1720 | { | |
1721 | spin_lock(&journal->j_state_lock); | |
1722 | if (journal->j_errno) | |
1723 | journal->j_flags |= JFS_ACK_ERR; | |
1724 | spin_unlock(&journal->j_state_lock); | |
1725 | } | |
1726 | ||
1727 | int journal_blocks_per_page(struct inode *inode) | |
1728 | { | |
1729 | return 1 << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
1730 | } | |
1731 | ||
1da177e4 LT |
1732 | /* |
1733 | * Journal_head storage management | |
1734 | */ | |
e18b890b | 1735 | static struct kmem_cache *journal_head_cache; |
1da177e4 LT |
1736 | #ifdef CONFIG_JBD_DEBUG |
1737 | static atomic_t nr_journal_heads = ATOMIC_INIT(0); | |
1738 | #endif | |
1739 | ||
1740 | static int journal_init_journal_head_cache(void) | |
1741 | { | |
1742 | int retval; | |
1743 | ||
1076d17a | 1744 | J_ASSERT(journal_head_cache == NULL); |
1da177e4 LT |
1745 | journal_head_cache = kmem_cache_create("journal_head", |
1746 | sizeof(struct journal_head), | |
1747 | 0, /* offset */ | |
e12ba74d | 1748 | SLAB_TEMPORARY, /* flags */ |
20c2df83 | 1749 | NULL); /* ctor */ |
1da177e4 | 1750 | retval = 0; |
1076d17a | 1751 | if (!journal_head_cache) { |
1da177e4 LT |
1752 | retval = -ENOMEM; |
1753 | printk(KERN_EMERG "JBD: no memory for journal_head cache\n"); | |
1754 | } | |
1755 | return retval; | |
1756 | } | |
1757 | ||
1758 | static void journal_destroy_journal_head_cache(void) | |
1759 | { | |
3850f7a5 DG |
1760 | if (journal_head_cache) { |
1761 | kmem_cache_destroy(journal_head_cache); | |
1762 | journal_head_cache = NULL; | |
1763 | } | |
1da177e4 LT |
1764 | } |
1765 | ||
1766 | /* | |
1767 | * journal_head splicing and dicing | |
1768 | */ | |
1769 | static struct journal_head *journal_alloc_journal_head(void) | |
1770 | { | |
1771 | struct journal_head *ret; | |
1da177e4 LT |
1772 | |
1773 | #ifdef CONFIG_JBD_DEBUG | |
1774 | atomic_inc(&nr_journal_heads); | |
1775 | #endif | |
1776 | ret = kmem_cache_alloc(journal_head_cache, GFP_NOFS); | |
c80544dc | 1777 | if (ret == NULL) { |
1da177e4 | 1778 | jbd_debug(1, "out of memory for journal_head\n"); |
f81e3d45 NK |
1779 | printk_ratelimited(KERN_NOTICE "ENOMEM in %s, retrying.\n", |
1780 | __func__); | |
1781 | ||
c80544dc | 1782 | while (ret == NULL) { |
1da177e4 LT |
1783 | yield(); |
1784 | ret = kmem_cache_alloc(journal_head_cache, GFP_NOFS); | |
1785 | } | |
1786 | } | |
1787 | return ret; | |
1788 | } | |
1789 | ||
1790 | static void journal_free_journal_head(struct journal_head *jh) | |
1791 | { | |
1792 | #ifdef CONFIG_JBD_DEBUG | |
1793 | atomic_dec(&nr_journal_heads); | |
c9cf5528 | 1794 | memset(jh, JBD_POISON_FREE, sizeof(*jh)); |
1da177e4 LT |
1795 | #endif |
1796 | kmem_cache_free(journal_head_cache, jh); | |
1797 | } | |
1798 | ||
1799 | /* | |
1800 | * A journal_head is attached to a buffer_head whenever JBD has an | |
1801 | * interest in the buffer. | |
1802 | * | |
1803 | * Whenever a buffer has an attached journal_head, its ->b_state:BH_JBD bit | |
1804 | * is set. This bit is tested in core kernel code where we need to take | |
1805 | * JBD-specific actions. Testing the zeroness of ->b_private is not reliable | |
1806 | * there. | |
1807 | * | |
1808 | * When a buffer has its BH_JBD bit set, its ->b_count is elevated by one. | |
1809 | * | |
1810 | * When a buffer has its BH_JBD bit set it is immune from being released by | |
1811 | * core kernel code, mainly via ->b_count. | |
1812 | * | |
bb189247 JK |
1813 | * A journal_head is detached from its buffer_head when the journal_head's |
1814 | * b_jcount reaches zero. Running transaction (b_transaction) and checkpoint | |
1815 | * transaction (b_cp_transaction) hold their references to b_jcount. | |
1da177e4 LT |
1816 | * |
1817 | * Various places in the kernel want to attach a journal_head to a buffer_head | |
1818 | * _before_ attaching the journal_head to a transaction. To protect the | |
1819 | * journal_head in this situation, journal_add_journal_head elevates the | |
1820 | * journal_head's b_jcount refcount by one. The caller must call | |
1821 | * journal_put_journal_head() to undo this. | |
1822 | * | |
1823 | * So the typical usage would be: | |
1824 | * | |
1825 | * (Attach a journal_head if needed. Increments b_jcount) | |
1826 | * struct journal_head *jh = journal_add_journal_head(bh); | |
1827 | * ... | |
bb189247 JK |
1828 | * (Get another reference for transaction) |
1829 | * journal_grab_journal_head(bh); | |
1830 | * jh->b_transaction = xxx; | |
1831 | * (Put original reference) | |
1832 | * journal_put_journal_head(jh); | |
1da177e4 LT |
1833 | */ |
1834 | ||
1835 | /* | |
1836 | * Give a buffer_head a journal_head. | |
1837 | * | |
1da177e4 LT |
1838 | * May sleep. |
1839 | */ | |
1840 | struct journal_head *journal_add_journal_head(struct buffer_head *bh) | |
1841 | { | |
1842 | struct journal_head *jh; | |
1843 | struct journal_head *new_jh = NULL; | |
1844 | ||
1845 | repeat: | |
1846 | if (!buffer_jbd(bh)) { | |
1847 | new_jh = journal_alloc_journal_head(); | |
1848 | memset(new_jh, 0, sizeof(*new_jh)); | |
1849 | } | |
1850 | ||
1851 | jbd_lock_bh_journal_head(bh); | |
1852 | if (buffer_jbd(bh)) { | |
1853 | jh = bh2jh(bh); | |
1854 | } else { | |
1855 | J_ASSERT_BH(bh, | |
1856 | (atomic_read(&bh->b_count) > 0) || | |
1857 | (bh->b_page && bh->b_page->mapping)); | |
1858 | ||
1859 | if (!new_jh) { | |
1860 | jbd_unlock_bh_journal_head(bh); | |
1861 | goto repeat; | |
1862 | } | |
1863 | ||
1864 | jh = new_jh; | |
1865 | new_jh = NULL; /* We consumed it */ | |
1866 | set_buffer_jbd(bh); | |
1867 | bh->b_private = jh; | |
1868 | jh->b_bh = bh; | |
1869 | get_bh(bh); | |
1870 | BUFFER_TRACE(bh, "added journal_head"); | |
1871 | } | |
1872 | jh->b_jcount++; | |
1873 | jbd_unlock_bh_journal_head(bh); | |
1874 | if (new_jh) | |
1875 | journal_free_journal_head(new_jh); | |
1876 | return bh->b_private; | |
1877 | } | |
1878 | ||
1879 | /* | |
1880 | * Grab a ref against this buffer_head's journal_head. If it ended up not | |
1881 | * having a journal_head, return NULL | |
1882 | */ | |
1883 | struct journal_head *journal_grab_journal_head(struct buffer_head *bh) | |
1884 | { | |
1885 | struct journal_head *jh = NULL; | |
1886 | ||
1887 | jbd_lock_bh_journal_head(bh); | |
1888 | if (buffer_jbd(bh)) { | |
1889 | jh = bh2jh(bh); | |
1890 | jh->b_jcount++; | |
1891 | } | |
1892 | jbd_unlock_bh_journal_head(bh); | |
1893 | return jh; | |
1894 | } | |
1895 | ||
1896 | static void __journal_remove_journal_head(struct buffer_head *bh) | |
1897 | { | |
1898 | struct journal_head *jh = bh2jh(bh); | |
1899 | ||
1900 | J_ASSERT_JH(jh, jh->b_jcount >= 0); | |
bb189247 JK |
1901 | J_ASSERT_JH(jh, jh->b_transaction == NULL); |
1902 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); | |
1903 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); | |
1904 | J_ASSERT_JH(jh, jh->b_jlist == BJ_None); | |
1905 | J_ASSERT_BH(bh, buffer_jbd(bh)); | |
1906 | J_ASSERT_BH(bh, jh2bh(jh) == bh); | |
1907 | BUFFER_TRACE(bh, "remove journal_head"); | |
1908 | if (jh->b_frozen_data) { | |
1909 | printk(KERN_WARNING "%s: freeing b_frozen_data\n", __func__); | |
1910 | jbd_free(jh->b_frozen_data, bh->b_size); | |
1da177e4 | 1911 | } |
bb189247 JK |
1912 | if (jh->b_committed_data) { |
1913 | printk(KERN_WARNING "%s: freeing b_committed_data\n", __func__); | |
1914 | jbd_free(jh->b_committed_data, bh->b_size); | |
1915 | } | |
1916 | bh->b_private = NULL; | |
1917 | jh->b_bh = NULL; /* debug, really */ | |
1918 | clear_buffer_jbd(bh); | |
1919 | journal_free_journal_head(jh); | |
1da177e4 LT |
1920 | } |
1921 | ||
1922 | /* | |
bb189247 | 1923 | * Drop a reference on the passed journal_head. If it fell to zero then |
1da177e4 LT |
1924 | * release the journal_head from the buffer_head. |
1925 | */ | |
1926 | void journal_put_journal_head(struct journal_head *jh) | |
1927 | { | |
1928 | struct buffer_head *bh = jh2bh(jh); | |
1929 | ||
1930 | jbd_lock_bh_journal_head(bh); | |
1931 | J_ASSERT_JH(jh, jh->b_jcount > 0); | |
1932 | --jh->b_jcount; | |
bb189247 | 1933 | if (!jh->b_jcount) { |
1da177e4 | 1934 | __journal_remove_journal_head(bh); |
bb189247 | 1935 | jbd_unlock_bh_journal_head(bh); |
1da177e4 | 1936 | __brelse(bh); |
bb189247 JK |
1937 | } else |
1938 | jbd_unlock_bh_journal_head(bh); | |
1da177e4 LT |
1939 | } |
1940 | ||
1941 | /* | |
c2a9159c | 1942 | * debugfs tunables |
1da177e4 | 1943 | */ |
c2a9159c | 1944 | #ifdef CONFIG_JBD_DEBUG |
1da177e4 | 1945 | |
c2a9159c JS |
1946 | u8 journal_enable_debug __read_mostly; |
1947 | EXPORT_SYMBOL(journal_enable_debug); | |
1da177e4 | 1948 | |
c2a9159c JS |
1949 | static struct dentry *jbd_debugfs_dir; |
1950 | static struct dentry *jbd_debug; | |
1da177e4 | 1951 | |
c2a9159c | 1952 | static void __init jbd_create_debugfs_entry(void) |
1da177e4 | 1953 | { |
c2a9159c JS |
1954 | jbd_debugfs_dir = debugfs_create_dir("jbd", NULL); |
1955 | if (jbd_debugfs_dir) | |
765f8361 | 1956 | jbd_debug = debugfs_create_u8("jbd-debug", S_IRUGO | S_IWUSR, |
c2a9159c JS |
1957 | jbd_debugfs_dir, |
1958 | &journal_enable_debug); | |
1da177e4 LT |
1959 | } |
1960 | ||
c2a9159c | 1961 | static void __exit jbd_remove_debugfs_entry(void) |
1da177e4 | 1962 | { |
c2a9159c JS |
1963 | debugfs_remove(jbd_debug); |
1964 | debugfs_remove(jbd_debugfs_dir); | |
1da177e4 LT |
1965 | } |
1966 | ||
c2a9159c | 1967 | #else |
1da177e4 | 1968 | |
c2a9159c | 1969 | static inline void jbd_create_debugfs_entry(void) |
1da177e4 | 1970 | { |
1da177e4 LT |
1971 | } |
1972 | ||
c2a9159c | 1973 | static inline void jbd_remove_debugfs_entry(void) |
1da177e4 | 1974 | { |
1da177e4 LT |
1975 | } |
1976 | ||
1da177e4 LT |
1977 | #endif |
1978 | ||
e18b890b | 1979 | struct kmem_cache *jbd_handle_cache; |
1da177e4 LT |
1980 | |
1981 | static int __init journal_init_handle_cache(void) | |
1982 | { | |
1983 | jbd_handle_cache = kmem_cache_create("journal_handle", | |
1984 | sizeof(handle_t), | |
1985 | 0, /* offset */ | |
e12ba74d | 1986 | SLAB_TEMPORARY, /* flags */ |
20c2df83 | 1987 | NULL); /* ctor */ |
1da177e4 LT |
1988 | if (jbd_handle_cache == NULL) { |
1989 | printk(KERN_EMERG "JBD: failed to create handle cache\n"); | |
1990 | return -ENOMEM; | |
1991 | } | |
1992 | return 0; | |
1993 | } | |
1994 | ||
1995 | static void journal_destroy_handle_cache(void) | |
1996 | { | |
1997 | if (jbd_handle_cache) | |
1998 | kmem_cache_destroy(jbd_handle_cache); | |
1999 | } | |
2000 | ||
2001 | /* | |
2002 | * Module startup and shutdown | |
2003 | */ | |
2004 | ||
2005 | static int __init journal_init_caches(void) | |
2006 | { | |
2007 | int ret; | |
2008 | ||
2009 | ret = journal_init_revoke_caches(); | |
2010 | if (ret == 0) | |
2011 | ret = journal_init_journal_head_cache(); | |
2012 | if (ret == 0) | |
2013 | ret = journal_init_handle_cache(); | |
2014 | return ret; | |
2015 | } | |
2016 | ||
2017 | static void journal_destroy_caches(void) | |
2018 | { | |
2019 | journal_destroy_revoke_caches(); | |
2020 | journal_destroy_journal_head_cache(); | |
2021 | journal_destroy_handle_cache(); | |
2022 | } | |
2023 | ||
2024 | static int __init journal_init(void) | |
2025 | { | |
2026 | int ret; | |
2027 | ||
2aed3484 | 2028 | BUILD_BUG_ON(sizeof(struct journal_superblock_s) != 1024); |
022a4a7b | 2029 | |
1da177e4 LT |
2030 | ret = journal_init_caches(); |
2031 | if (ret != 0) | |
2032 | journal_destroy_caches(); | |
c2a9159c | 2033 | jbd_create_debugfs_entry(); |
1da177e4 LT |
2034 | return ret; |
2035 | } | |
2036 | ||
2037 | static void __exit journal_exit(void) | |
2038 | { | |
2039 | #ifdef CONFIG_JBD_DEBUG | |
2040 | int n = atomic_read(&nr_journal_heads); | |
2041 | if (n) | |
2042 | printk(KERN_EMERG "JBD: leaked %d journal_heads!\n", n); | |
2043 | #endif | |
c2a9159c | 2044 | jbd_remove_debugfs_entry(); |
1da177e4 LT |
2045 | journal_destroy_caches(); |
2046 | } | |
2047 | ||
2048 | MODULE_LICENSE("GPL"); | |
2049 | module_init(journal_init); | |
2050 | module_exit(journal_exit); | |
2051 |