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 | ||
8e85fb3f JL |
745 | struct jbd2_stats_proc_session { |
746 | journal_t *journal; | |
747 | struct transaction_stats_s *stats; | |
748 | int start; | |
749 | int max; | |
750 | }; | |
751 | ||
8e85fb3f JL |
752 | static void *jbd2_seq_info_start(struct seq_file *seq, loff_t *pos) |
753 | { | |
754 | return *pos ? NULL : SEQ_START_TOKEN; | |
755 | } | |
756 | ||
757 | static void *jbd2_seq_info_next(struct seq_file *seq, void *v, loff_t *pos) | |
758 | { | |
759 | return NULL; | |
760 | } | |
761 | ||
762 | static int jbd2_seq_info_show(struct seq_file *seq, void *v) | |
763 | { | |
764 | struct jbd2_stats_proc_session *s = seq->private; | |
765 | ||
766 | if (v != SEQ_START_TOKEN) | |
767 | return 0; | |
bf699327 | 768 | seq_printf(seq, "%lu transaction, each up to %u blocks\n", |
8e85fb3f JL |
769 | s->stats->ts_tid, |
770 | s->journal->j_max_transaction_buffers); | |
771 | if (s->stats->ts_tid == 0) | |
772 | return 0; | |
773 | seq_printf(seq, "average: \n %ums waiting for transaction\n", | |
bf699327 | 774 | jiffies_to_msecs(s->stats->run.rs_wait / s->stats->ts_tid)); |
8e85fb3f | 775 | seq_printf(seq, " %ums running transaction\n", |
bf699327 | 776 | jiffies_to_msecs(s->stats->run.rs_running / s->stats->ts_tid)); |
8e85fb3f | 777 | seq_printf(seq, " %ums transaction was being locked\n", |
bf699327 | 778 | jiffies_to_msecs(s->stats->run.rs_locked / s->stats->ts_tid)); |
8e85fb3f | 779 | seq_printf(seq, " %ums flushing data (in ordered mode)\n", |
bf699327 | 780 | jiffies_to_msecs(s->stats->run.rs_flushing / s->stats->ts_tid)); |
8e85fb3f | 781 | seq_printf(seq, " %ums logging transaction\n", |
bf699327 | 782 | jiffies_to_msecs(s->stats->run.rs_logging / s->stats->ts_tid)); |
c225aa57 SHT |
783 | seq_printf(seq, " %lluus average transaction commit time\n", |
784 | div_u64(s->journal->j_average_commit_time, 1000)); | |
8e85fb3f | 785 | seq_printf(seq, " %lu handles per transaction\n", |
bf699327 | 786 | s->stats->run.rs_handle_count / s->stats->ts_tid); |
8e85fb3f | 787 | seq_printf(seq, " %lu blocks per transaction\n", |
bf699327 | 788 | s->stats->run.rs_blocks / s->stats->ts_tid); |
8e85fb3f | 789 | seq_printf(seq, " %lu logged blocks per transaction\n", |
bf699327 | 790 | s->stats->run.rs_blocks_logged / s->stats->ts_tid); |
8e85fb3f JL |
791 | return 0; |
792 | } | |
793 | ||
794 | static void jbd2_seq_info_stop(struct seq_file *seq, void *v) | |
795 | { | |
796 | } | |
797 | ||
88e9d34c | 798 | static const struct seq_operations jbd2_seq_info_ops = { |
8e85fb3f JL |
799 | .start = jbd2_seq_info_start, |
800 | .next = jbd2_seq_info_next, | |
801 | .stop = jbd2_seq_info_stop, | |
802 | .show = jbd2_seq_info_show, | |
803 | }; | |
804 | ||
805 | static int jbd2_seq_info_open(struct inode *inode, struct file *file) | |
806 | { | |
807 | journal_t *journal = PDE(inode)->data; | |
808 | struct jbd2_stats_proc_session *s; | |
809 | int rc, size; | |
810 | ||
811 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
812 | if (s == NULL) | |
813 | return -ENOMEM; | |
814 | size = sizeof(struct transaction_stats_s); | |
815 | s->stats = kmalloc(size, GFP_KERNEL); | |
816 | if (s->stats == NULL) { | |
817 | kfree(s); | |
818 | return -ENOMEM; | |
819 | } | |
820 | spin_lock(&journal->j_history_lock); | |
821 | memcpy(s->stats, &journal->j_stats, size); | |
822 | s->journal = journal; | |
823 | spin_unlock(&journal->j_history_lock); | |
824 | ||
825 | rc = seq_open(file, &jbd2_seq_info_ops); | |
826 | if (rc == 0) { | |
827 | struct seq_file *m = file->private_data; | |
828 | m->private = s; | |
829 | } else { | |
830 | kfree(s->stats); | |
831 | kfree(s); | |
832 | } | |
833 | return rc; | |
834 | ||
835 | } | |
836 | ||
837 | static int jbd2_seq_info_release(struct inode *inode, struct file *file) | |
838 | { | |
839 | struct seq_file *seq = file->private_data; | |
840 | struct jbd2_stats_proc_session *s = seq->private; | |
841 | kfree(s->stats); | |
842 | kfree(s); | |
843 | return seq_release(inode, file); | |
844 | } | |
845 | ||
828c0950 | 846 | static const struct file_operations jbd2_seq_info_fops = { |
8e85fb3f JL |
847 | .owner = THIS_MODULE, |
848 | .open = jbd2_seq_info_open, | |
849 | .read = seq_read, | |
850 | .llseek = seq_lseek, | |
851 | .release = jbd2_seq_info_release, | |
852 | }; | |
853 | ||
854 | static struct proc_dir_entry *proc_jbd2_stats; | |
855 | ||
856 | static void jbd2_stats_proc_init(journal_t *journal) | |
857 | { | |
05496769 | 858 | journal->j_proc_entry = proc_mkdir(journal->j_devname, proc_jbd2_stats); |
8e85fb3f | 859 | if (journal->j_proc_entry) { |
79da3664 DL |
860 | proc_create_data("info", S_IRUGO, journal->j_proc_entry, |
861 | &jbd2_seq_info_fops, journal); | |
8e85fb3f JL |
862 | } |
863 | } | |
864 | ||
865 | static void jbd2_stats_proc_exit(journal_t *journal) | |
866 | { | |
8e85fb3f | 867 | remove_proc_entry("info", journal->j_proc_entry); |
05496769 | 868 | remove_proc_entry(journal->j_devname, proc_jbd2_stats); |
8e85fb3f JL |
869 | } |
870 | ||
470decc6 DK |
871 | /* |
872 | * Management for journal control blocks: functions to create and | |
873 | * destroy journal_t structures, and to initialise and read existing | |
874 | * journal blocks from disk. */ | |
875 | ||
876 | /* First: create and setup a journal_t object in memory. We initialise | |
877 | * very few fields yet: that has to wait until we have created the | |
878 | * journal structures from from scratch, or loaded them from disk. */ | |
879 | ||
880 | static journal_t * journal_init_common (void) | |
881 | { | |
882 | journal_t *journal; | |
883 | int err; | |
884 | ||
3ebfdf88 | 885 | journal = kzalloc(sizeof(*journal), GFP_KERNEL); |
470decc6 | 886 | if (!journal) |
b7271b0a | 887 | return NULL; |
470decc6 DK |
888 | |
889 | init_waitqueue_head(&journal->j_wait_transaction_locked); | |
890 | init_waitqueue_head(&journal->j_wait_logspace); | |
891 | init_waitqueue_head(&journal->j_wait_done_commit); | |
892 | init_waitqueue_head(&journal->j_wait_checkpoint); | |
893 | init_waitqueue_head(&journal->j_wait_commit); | |
894 | init_waitqueue_head(&journal->j_wait_updates); | |
895 | mutex_init(&journal->j_barrier); | |
896 | mutex_init(&journal->j_checkpoint_mutex); | |
897 | spin_lock_init(&journal->j_revoke_lock); | |
898 | spin_lock_init(&journal->j_list_lock); | |
a931da6a | 899 | rwlock_init(&journal->j_state_lock); |
470decc6 | 900 | |
cd02ff0b | 901 | journal->j_commit_interval = (HZ * JBD2_DEFAULT_MAX_COMMIT_AGE); |
30773840 TT |
902 | journal->j_min_batch_time = 0; |
903 | journal->j_max_batch_time = 15000; /* 15ms */ | |
470decc6 DK |
904 | |
905 | /* The journal is marked for error until we succeed with recovery! */ | |
f7f4bccb | 906 | journal->j_flags = JBD2_ABORT; |
470decc6 DK |
907 | |
908 | /* Set up a default-sized revoke table for the new mount. */ | |
f7f4bccb | 909 | err = jbd2_journal_init_revoke(journal, JOURNAL_REVOKE_DEFAULT_HASH); |
470decc6 DK |
910 | if (err) { |
911 | kfree(journal); | |
b7271b0a | 912 | return NULL; |
470decc6 | 913 | } |
8e85fb3f | 914 | |
bf699327 | 915 | spin_lock_init(&journal->j_history_lock); |
8e85fb3f | 916 | |
470decc6 | 917 | return journal; |
470decc6 DK |
918 | } |
919 | ||
f7f4bccb | 920 | /* jbd2_journal_init_dev and jbd2_journal_init_inode: |
470decc6 DK |
921 | * |
922 | * Create a journal structure assigned some fixed set of disk blocks to | |
923 | * the journal. We don't actually touch those disk blocks yet, but we | |
924 | * need to set up all of the mapping information to tell the journaling | |
925 | * system where the journal blocks are. | |
926 | * | |
927 | */ | |
928 | ||
929 | /** | |
5648ba5b | 930 | * journal_t * jbd2_journal_init_dev() - creates and initialises a journal structure |
470decc6 DK |
931 | * @bdev: Block device on which to create the journal |
932 | * @fs_dev: Device which hold journalled filesystem for this journal. | |
933 | * @start: Block nr Start of journal. | |
934 | * @len: Length of the journal in blocks. | |
935 | * @blocksize: blocksize of journalling device | |
5648ba5b RD |
936 | * |
937 | * Returns: a newly created journal_t * | |
470decc6 | 938 | * |
f7f4bccb | 939 | * jbd2_journal_init_dev creates a journal which maps a fixed contiguous |
470decc6 DK |
940 | * range of blocks on an arbitrary block device. |
941 | * | |
942 | */ | |
f7f4bccb | 943 | journal_t * jbd2_journal_init_dev(struct block_device *bdev, |
470decc6 | 944 | struct block_device *fs_dev, |
18eba7aa | 945 | unsigned long long start, int len, int blocksize) |
470decc6 DK |
946 | { |
947 | journal_t *journal = journal_init_common(); | |
948 | struct buffer_head *bh; | |
05496769 | 949 | char *p; |
470decc6 DK |
950 | int n; |
951 | ||
952 | if (!journal) | |
953 | return NULL; | |
954 | ||
955 | /* journal descriptor can store up to n blocks -bzzz */ | |
956 | journal->j_blocksize = blocksize; | |
0587aa3d | 957 | journal->j_dev = bdev; |
958 | journal->j_fs_dev = fs_dev; | |
959 | journal->j_blk_offset = start; | |
960 | journal->j_maxlen = len; | |
961 | bdevname(journal->j_dev, journal->j_devname); | |
962 | p = journal->j_devname; | |
963 | while ((p = strchr(p, '/'))) | |
964 | *p = '!'; | |
4b905671 | 965 | jbd2_stats_proc_init(journal); |
470decc6 DK |
966 | n = journal->j_blocksize / sizeof(journal_block_tag_t); |
967 | journal->j_wbufsize = n; | |
968 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
969 | if (!journal->j_wbuf) { | |
25985edc | 970 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
329d291f | 971 | __func__); |
4b905671 | 972 | goto out_err; |
470decc6 | 973 | } |
470decc6 DK |
974 | |
975 | bh = __getblk(journal->j_dev, start, journal->j_blocksize); | |
4b905671 JK |
976 | if (!bh) { |
977 | printk(KERN_ERR | |
978 | "%s: Cannot get buffer for journal superblock\n", | |
979 | __func__); | |
980 | goto out_err; | |
981 | } | |
470decc6 DK |
982 | journal->j_sb_buffer = bh; |
983 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
4b905671 | 984 | |
470decc6 | 985 | return journal; |
4b905671 | 986 | out_err: |
7b02bec0 | 987 | kfree(journal->j_wbuf); |
4b905671 JK |
988 | jbd2_stats_proc_exit(journal); |
989 | kfree(journal); | |
990 | return NULL; | |
470decc6 DK |
991 | } |
992 | ||
993 | /** | |
f7f4bccb | 994 | * journal_t * jbd2_journal_init_inode () - creates a journal which maps to a inode. |
470decc6 DK |
995 | * @inode: An inode to create the journal in |
996 | * | |
f7f4bccb | 997 | * jbd2_journal_init_inode creates a journal which maps an on-disk inode as |
470decc6 DK |
998 | * the journal. The inode must exist already, must support bmap() and |
999 | * must have all data blocks preallocated. | |
1000 | */ | |
f7f4bccb | 1001 | journal_t * jbd2_journal_init_inode (struct inode *inode) |
470decc6 DK |
1002 | { |
1003 | struct buffer_head *bh; | |
1004 | journal_t *journal = journal_init_common(); | |
05496769 | 1005 | char *p; |
470decc6 DK |
1006 | int err; |
1007 | int n; | |
18eba7aa | 1008 | unsigned long long blocknr; |
470decc6 DK |
1009 | |
1010 | if (!journal) | |
1011 | return NULL; | |
1012 | ||
1013 | journal->j_dev = journal->j_fs_dev = inode->i_sb->s_bdev; | |
1014 | journal->j_inode = inode; | |
05496769 TT |
1015 | bdevname(journal->j_dev, journal->j_devname); |
1016 | p = journal->j_devname; | |
1017 | while ((p = strchr(p, '/'))) | |
1018 | *p = '!'; | |
1019 | p = journal->j_devname + strlen(journal->j_devname); | |
90576c0b | 1020 | sprintf(p, "-%lu", journal->j_inode->i_ino); |
470decc6 DK |
1021 | jbd_debug(1, |
1022 | "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n", | |
1023 | journal, inode->i_sb->s_id, inode->i_ino, | |
1024 | (long long) inode->i_size, | |
1025 | inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize); | |
1026 | ||
1027 | journal->j_maxlen = inode->i_size >> inode->i_sb->s_blocksize_bits; | |
1028 | journal->j_blocksize = inode->i_sb->s_blocksize; | |
8e85fb3f | 1029 | jbd2_stats_proc_init(journal); |
470decc6 DK |
1030 | |
1031 | /* journal descriptor can store up to n blocks -bzzz */ | |
1032 | n = journal->j_blocksize / sizeof(journal_block_tag_t); | |
1033 | journal->j_wbufsize = n; | |
1034 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
1035 | if (!journal->j_wbuf) { | |
25985edc | 1036 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
329d291f | 1037 | __func__); |
4b905671 | 1038 | goto out_err; |
470decc6 DK |
1039 | } |
1040 | ||
f7f4bccb | 1041 | err = jbd2_journal_bmap(journal, 0, &blocknr); |
470decc6 DK |
1042 | /* If that failed, give up */ |
1043 | if (err) { | |
3c26bdb4 | 1044 | printk(KERN_ERR "%s: Cannot locate journal superblock\n", |
329d291f | 1045 | __func__); |
4b905671 | 1046 | goto out_err; |
470decc6 DK |
1047 | } |
1048 | ||
1049 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
4b905671 JK |
1050 | if (!bh) { |
1051 | printk(KERN_ERR | |
1052 | "%s: Cannot get buffer for journal superblock\n", | |
1053 | __func__); | |
1054 | goto out_err; | |
1055 | } | |
470decc6 DK |
1056 | journal->j_sb_buffer = bh; |
1057 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
1058 | ||
1059 | return journal; | |
4b905671 | 1060 | out_err: |
7b02bec0 | 1061 | kfree(journal->j_wbuf); |
4b905671 JK |
1062 | jbd2_stats_proc_exit(journal); |
1063 | kfree(journal); | |
1064 | return NULL; | |
470decc6 DK |
1065 | } |
1066 | ||
1067 | /* | |
1068 | * If the journal init or create aborts, we need to mark the journal | |
1069 | * superblock as being NULL to prevent the journal destroy from writing | |
1070 | * back a bogus superblock. | |
1071 | */ | |
1072 | static void journal_fail_superblock (journal_t *journal) | |
1073 | { | |
1074 | struct buffer_head *bh = journal->j_sb_buffer; | |
1075 | brelse(bh); | |
1076 | journal->j_sb_buffer = NULL; | |
1077 | } | |
1078 | ||
1079 | /* | |
1080 | * Given a journal_t structure, initialise the various fields for | |
1081 | * startup of a new journaling session. We use this both when creating | |
1082 | * a journal, and after recovering an old journal to reset it for | |
1083 | * subsequent use. | |
1084 | */ | |
1085 | ||
1086 | static int journal_reset(journal_t *journal) | |
1087 | { | |
1088 | journal_superblock_t *sb = journal->j_superblock; | |
18eba7aa | 1089 | unsigned long long first, last; |
470decc6 DK |
1090 | |
1091 | first = be32_to_cpu(sb->s_first); | |
1092 | last = be32_to_cpu(sb->s_maxlen); | |
f6f50e28 | 1093 | if (first + JBD2_MIN_JOURNAL_BLOCKS > last + 1) { |
f2a44523 | 1094 | printk(KERN_ERR "JBD2: Journal too short (blocks %llu-%llu).\n", |
f6f50e28 JK |
1095 | first, last); |
1096 | journal_fail_superblock(journal); | |
1097 | return -EINVAL; | |
1098 | } | |
470decc6 DK |
1099 | |
1100 | journal->j_first = first; | |
1101 | journal->j_last = last; | |
1102 | ||
1103 | journal->j_head = first; | |
1104 | journal->j_tail = first; | |
1105 | journal->j_free = last - first; | |
1106 | ||
1107 | journal->j_tail_sequence = journal->j_transaction_sequence; | |
1108 | journal->j_commit_sequence = journal->j_transaction_sequence - 1; | |
1109 | journal->j_commit_request = journal->j_commit_sequence; | |
1110 | ||
1111 | journal->j_max_transaction_buffers = journal->j_maxlen / 4; | |
1112 | ||
1113 | /* Add the dynamic fields and write it to disk. */ | |
f7f4bccb | 1114 | jbd2_journal_update_superblock(journal, 1); |
97f06784 | 1115 | return jbd2_journal_start_thread(journal); |
470decc6 DK |
1116 | } |
1117 | ||
470decc6 | 1118 | /** |
f7f4bccb | 1119 | * void jbd2_journal_update_superblock() - Update journal sb on disk. |
470decc6 DK |
1120 | * @journal: The journal to update. |
1121 | * @wait: Set to '0' if you don't want to wait for IO completion. | |
1122 | * | |
1123 | * Update a journal's dynamic superblock fields and write it to disk, | |
1124 | * optionally waiting for the IO to complete. | |
1125 | */ | |
f7f4bccb | 1126 | void jbd2_journal_update_superblock(journal_t *journal, int wait) |
470decc6 DK |
1127 | { |
1128 | journal_superblock_t *sb = journal->j_superblock; | |
1129 | struct buffer_head *bh = journal->j_sb_buffer; | |
1130 | ||
1131 | /* | |
1132 | * As a special case, if the on-disk copy is already marked as needing | |
1133 | * no recovery (s_start == 0) and there are no outstanding transactions | |
1134 | * in the filesystem, then we can safely defer the superblock update | |
f7f4bccb | 1135 | * until the next commit by setting JBD2_FLUSHED. This avoids |
470decc6 DK |
1136 | * attempting a write to a potential-readonly device. |
1137 | */ | |
1138 | if (sb->s_start == 0 && journal->j_tail_sequence == | |
1139 | journal->j_transaction_sequence) { | |
f2a44523 | 1140 | jbd_debug(1, "JBD2: Skipping superblock update on recovered sb " |
470decc6 DK |
1141 | "(start %ld, seq %d, errno %d)\n", |
1142 | journal->j_tail, journal->j_tail_sequence, | |
1143 | journal->j_errno); | |
1144 | goto out; | |
1145 | } | |
1146 | ||
914258bf TT |
1147 | if (buffer_write_io_error(bh)) { |
1148 | /* | |
1149 | * Oh, dear. A previous attempt to write the journal | |
1150 | * superblock failed. This could happen because the | |
1151 | * USB device was yanked out. Or it could happen to | |
1152 | * be a transient write error and maybe the block will | |
1153 | * be remapped. Nothing we can do but to retry the | |
1154 | * write and hope for the best. | |
1155 | */ | |
1156 | printk(KERN_ERR "JBD2: previous I/O error detected " | |
1157 | "for journal superblock update for %s.\n", | |
1158 | journal->j_devname); | |
1159 | clear_buffer_write_io_error(bh); | |
1160 | set_buffer_uptodate(bh); | |
1161 | } | |
1162 | ||
a931da6a | 1163 | read_lock(&journal->j_state_lock); |
f2a44523 | 1164 | jbd_debug(1, "JBD2: updating superblock (start %ld, seq %d, errno %d)\n", |
470decc6 DK |
1165 | journal->j_tail, journal->j_tail_sequence, journal->j_errno); |
1166 | ||
1167 | sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); | |
1168 | sb->s_start = cpu_to_be32(journal->j_tail); | |
1169 | sb->s_errno = cpu_to_be32(journal->j_errno); | |
a931da6a | 1170 | read_unlock(&journal->j_state_lock); |
470decc6 DK |
1171 | |
1172 | BUFFER_TRACE(bh, "marking dirty"); | |
1173 | mark_buffer_dirty(bh); | |
914258bf | 1174 | if (wait) { |
470decc6 | 1175 | sync_dirty_buffer(bh); |
914258bf TT |
1176 | if (buffer_write_io_error(bh)) { |
1177 | printk(KERN_ERR "JBD2: I/O error detected " | |
1178 | "when updating journal superblock for %s.\n", | |
1179 | journal->j_devname); | |
1180 | clear_buffer_write_io_error(bh); | |
1181 | set_buffer_uptodate(bh); | |
1182 | } | |
1183 | } else | |
9cb569d6 | 1184 | write_dirty_buffer(bh, WRITE); |
470decc6 | 1185 | |
2201c590 SA |
1186 | trace_jbd2_update_superblock_end(journal, wait); |
1187 | ||
470decc6 DK |
1188 | out: |
1189 | /* If we have just flushed the log (by marking s_start==0), then | |
1190 | * any future commit will have to be careful to update the | |
1191 | * superblock again to re-record the true start of the log. */ | |
1192 | ||
a931da6a | 1193 | write_lock(&journal->j_state_lock); |
470decc6 | 1194 | if (sb->s_start) |
f7f4bccb | 1195 | journal->j_flags &= ~JBD2_FLUSHED; |
470decc6 | 1196 | else |
f7f4bccb | 1197 | journal->j_flags |= JBD2_FLUSHED; |
a931da6a | 1198 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1199 | } |
1200 | ||
1201 | /* | |
1202 | * Read the superblock for a given journal, performing initial | |
1203 | * validation of the format. | |
1204 | */ | |
1205 | ||
1206 | static int journal_get_superblock(journal_t *journal) | |
1207 | { | |
1208 | struct buffer_head *bh; | |
1209 | journal_superblock_t *sb; | |
1210 | int err = -EIO; | |
1211 | ||
1212 | bh = journal->j_sb_buffer; | |
1213 | ||
1214 | J_ASSERT(bh != NULL); | |
1215 | if (!buffer_uptodate(bh)) { | |
1216 | ll_rw_block(READ, 1, &bh); | |
1217 | wait_on_buffer(bh); | |
1218 | if (!buffer_uptodate(bh)) { | |
f2a44523 EG |
1219 | printk(KERN_ERR |
1220 | "JBD2: IO error reading journal superblock\n"); | |
470decc6 DK |
1221 | goto out; |
1222 | } | |
1223 | } | |
1224 | ||
1225 | sb = journal->j_superblock; | |
1226 | ||
1227 | err = -EINVAL; | |
1228 | ||
f7f4bccb | 1229 | if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) || |
470decc6 | 1230 | sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) { |
f2a44523 | 1231 | printk(KERN_WARNING "JBD2: no valid journal superblock found\n"); |
470decc6 DK |
1232 | goto out; |
1233 | } | |
1234 | ||
1235 | switch(be32_to_cpu(sb->s_header.h_blocktype)) { | |
f7f4bccb | 1236 | case JBD2_SUPERBLOCK_V1: |
470decc6 DK |
1237 | journal->j_format_version = 1; |
1238 | break; | |
f7f4bccb | 1239 | case JBD2_SUPERBLOCK_V2: |
470decc6 DK |
1240 | journal->j_format_version = 2; |
1241 | break; | |
1242 | default: | |
f2a44523 | 1243 | printk(KERN_WARNING "JBD2: unrecognised superblock format ID\n"); |
470decc6 DK |
1244 | goto out; |
1245 | } | |
1246 | ||
1247 | if (be32_to_cpu(sb->s_maxlen) < journal->j_maxlen) | |
1248 | journal->j_maxlen = be32_to_cpu(sb->s_maxlen); | |
1249 | else if (be32_to_cpu(sb->s_maxlen) > journal->j_maxlen) { | |
f2a44523 | 1250 | printk(KERN_WARNING "JBD2: journal file too short\n"); |
470decc6 DK |
1251 | goto out; |
1252 | } | |
1253 | ||
8762202d EG |
1254 | if (be32_to_cpu(sb->s_first) == 0 || |
1255 | be32_to_cpu(sb->s_first) >= journal->j_maxlen) { | |
1256 | printk(KERN_WARNING | |
1257 | "JBD2: Invalid start block of journal: %u\n", | |
1258 | be32_to_cpu(sb->s_first)); | |
1259 | goto out; | |
1260 | } | |
1261 | ||
470decc6 DK |
1262 | return 0; |
1263 | ||
1264 | out: | |
1265 | journal_fail_superblock(journal); | |
1266 | return err; | |
1267 | } | |
1268 | ||
1269 | /* | |
1270 | * Load the on-disk journal superblock and read the key fields into the | |
1271 | * journal_t. | |
1272 | */ | |
1273 | ||
1274 | static int load_superblock(journal_t *journal) | |
1275 | { | |
1276 | int err; | |
1277 | journal_superblock_t *sb; | |
1278 | ||
1279 | err = journal_get_superblock(journal); | |
1280 | if (err) | |
1281 | return err; | |
1282 | ||
1283 | sb = journal->j_superblock; | |
1284 | ||
1285 | journal->j_tail_sequence = be32_to_cpu(sb->s_sequence); | |
1286 | journal->j_tail = be32_to_cpu(sb->s_start); | |
1287 | journal->j_first = be32_to_cpu(sb->s_first); | |
1288 | journal->j_last = be32_to_cpu(sb->s_maxlen); | |
1289 | journal->j_errno = be32_to_cpu(sb->s_errno); | |
1290 | ||
1291 | return 0; | |
1292 | } | |
1293 | ||
1294 | ||
1295 | /** | |
f7f4bccb | 1296 | * int jbd2_journal_load() - Read journal from disk. |
470decc6 DK |
1297 | * @journal: Journal to act on. |
1298 | * | |
1299 | * Given a journal_t structure which tells us which disk blocks contain | |
1300 | * a journal, read the journal from disk to initialise the in-memory | |
1301 | * structures. | |
1302 | */ | |
f7f4bccb | 1303 | int jbd2_journal_load(journal_t *journal) |
470decc6 DK |
1304 | { |
1305 | int err; | |
1306 | journal_superblock_t *sb; | |
1307 | ||
1308 | err = load_superblock(journal); | |
1309 | if (err) | |
1310 | return err; | |
1311 | ||
1312 | sb = journal->j_superblock; | |
1313 | /* If this is a V2 superblock, then we have to check the | |
1314 | * features flags on it. */ | |
1315 | ||
1316 | if (journal->j_format_version >= 2) { | |
1317 | if ((sb->s_feature_ro_compat & | |
f7f4bccb | 1318 | ~cpu_to_be32(JBD2_KNOWN_ROCOMPAT_FEATURES)) || |
470decc6 | 1319 | (sb->s_feature_incompat & |
f7f4bccb | 1320 | ~cpu_to_be32(JBD2_KNOWN_INCOMPAT_FEATURES))) { |
f2a44523 EG |
1321 | printk(KERN_WARNING |
1322 | "JBD2: Unrecognised features on journal\n"); | |
470decc6 DK |
1323 | return -EINVAL; |
1324 | } | |
1325 | } | |
1326 | ||
d2eecb03 TT |
1327 | /* |
1328 | * Create a slab for this blocksize | |
1329 | */ | |
1330 | err = jbd2_journal_create_slab(be32_to_cpu(sb->s_blocksize)); | |
1331 | if (err) | |
1332 | return err; | |
1333 | ||
470decc6 DK |
1334 | /* Let the recovery code check whether it needs to recover any |
1335 | * data from the journal. */ | |
f7f4bccb | 1336 | if (jbd2_journal_recover(journal)) |
470decc6 DK |
1337 | goto recovery_error; |
1338 | ||
e6a47428 TT |
1339 | if (journal->j_failed_commit) { |
1340 | printk(KERN_ERR "JBD2: journal transaction %u on %s " | |
1341 | "is corrupt.\n", journal->j_failed_commit, | |
1342 | journal->j_devname); | |
1343 | return -EIO; | |
1344 | } | |
1345 | ||
470decc6 DK |
1346 | /* OK, we've finished with the dynamic journal bits: |
1347 | * reinitialise the dynamic contents of the superblock in memory | |
1348 | * and reset them on disk. */ | |
1349 | if (journal_reset(journal)) | |
1350 | goto recovery_error; | |
1351 | ||
f7f4bccb MC |
1352 | journal->j_flags &= ~JBD2_ABORT; |
1353 | journal->j_flags |= JBD2_LOADED; | |
470decc6 DK |
1354 | return 0; |
1355 | ||
1356 | recovery_error: | |
f2a44523 | 1357 | printk(KERN_WARNING "JBD2: recovery failed\n"); |
470decc6 DK |
1358 | return -EIO; |
1359 | } | |
1360 | ||
1361 | /** | |
f7f4bccb | 1362 | * void jbd2_journal_destroy() - Release a journal_t structure. |
470decc6 DK |
1363 | * @journal: Journal to act on. |
1364 | * | |
1365 | * Release a journal_t structure once it is no longer in use by the | |
1366 | * journaled object. | |
44519faf | 1367 | * Return <0 if we couldn't clean up the journal. |
470decc6 | 1368 | */ |
44519faf | 1369 | int jbd2_journal_destroy(journal_t *journal) |
470decc6 | 1370 | { |
44519faf HK |
1371 | int err = 0; |
1372 | ||
470decc6 DK |
1373 | /* Wait for the commit thread to wake up and die. */ |
1374 | journal_kill_thread(journal); | |
1375 | ||
1376 | /* Force a final log commit */ | |
1377 | if (journal->j_running_transaction) | |
f7f4bccb | 1378 | jbd2_journal_commit_transaction(journal); |
470decc6 DK |
1379 | |
1380 | /* Force any old transactions to disk */ | |
1381 | ||
1382 | /* Totally anal locking here... */ | |
1383 | spin_lock(&journal->j_list_lock); | |
1384 | while (journal->j_checkpoint_transactions != NULL) { | |
1385 | spin_unlock(&journal->j_list_lock); | |
1a0d3786 | 1386 | mutex_lock(&journal->j_checkpoint_mutex); |
f7f4bccb | 1387 | jbd2_log_do_checkpoint(journal); |
1a0d3786 | 1388 | mutex_unlock(&journal->j_checkpoint_mutex); |
470decc6 DK |
1389 | spin_lock(&journal->j_list_lock); |
1390 | } | |
1391 | ||
1392 | J_ASSERT(journal->j_running_transaction == NULL); | |
1393 | J_ASSERT(journal->j_committing_transaction == NULL); | |
1394 | J_ASSERT(journal->j_checkpoint_transactions == NULL); | |
1395 | spin_unlock(&journal->j_list_lock); | |
1396 | ||
470decc6 | 1397 | if (journal->j_sb_buffer) { |
44519faf HK |
1398 | if (!is_journal_aborted(journal)) { |
1399 | /* We can now mark the journal as empty. */ | |
1400 | journal->j_tail = 0; | |
1401 | journal->j_tail_sequence = | |
1402 | ++journal->j_transaction_sequence; | |
1403 | jbd2_journal_update_superblock(journal, 1); | |
1404 | } else { | |
1405 | err = -EIO; | |
1406 | } | |
470decc6 DK |
1407 | brelse(journal->j_sb_buffer); |
1408 | } | |
1409 | ||
8e85fb3f JL |
1410 | if (journal->j_proc_entry) |
1411 | jbd2_stats_proc_exit(journal); | |
470decc6 DK |
1412 | if (journal->j_inode) |
1413 | iput(journal->j_inode); | |
1414 | if (journal->j_revoke) | |
f7f4bccb | 1415 | jbd2_journal_destroy_revoke(journal); |
470decc6 DK |
1416 | kfree(journal->j_wbuf); |
1417 | kfree(journal); | |
44519faf HK |
1418 | |
1419 | return err; | |
470decc6 DK |
1420 | } |
1421 | ||
1422 | ||
1423 | /** | |
f7f4bccb | 1424 | *int jbd2_journal_check_used_features () - Check if features specified are used. |
470decc6 DK |
1425 | * @journal: Journal to check. |
1426 | * @compat: bitmask of compatible features | |
1427 | * @ro: bitmask of features that force read-only mount | |
1428 | * @incompat: bitmask of incompatible features | |
1429 | * | |
1430 | * Check whether the journal uses all of a given set of | |
1431 | * features. Return true (non-zero) if it does. | |
1432 | **/ | |
1433 | ||
f7f4bccb | 1434 | int jbd2_journal_check_used_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1435 | unsigned long ro, unsigned long incompat) |
1436 | { | |
1437 | journal_superblock_t *sb; | |
1438 | ||
1439 | if (!compat && !ro && !incompat) | |
1440 | return 1; | |
1113e1b5 PL |
1441 | /* Load journal superblock if it is not loaded yet. */ |
1442 | if (journal->j_format_version == 0 && | |
1443 | journal_get_superblock(journal) != 0) | |
1444 | return 0; | |
470decc6 DK |
1445 | if (journal->j_format_version == 1) |
1446 | return 0; | |
1447 | ||
1448 | sb = journal->j_superblock; | |
1449 | ||
1450 | if (((be32_to_cpu(sb->s_feature_compat) & compat) == compat) && | |
1451 | ((be32_to_cpu(sb->s_feature_ro_compat) & ro) == ro) && | |
1452 | ((be32_to_cpu(sb->s_feature_incompat) & incompat) == incompat)) | |
1453 | return 1; | |
1454 | ||
1455 | return 0; | |
1456 | } | |
1457 | ||
1458 | /** | |
f7f4bccb | 1459 | * int jbd2_journal_check_available_features() - Check feature set in journalling layer |
470decc6 DK |
1460 | * @journal: Journal to check. |
1461 | * @compat: bitmask of compatible features | |
1462 | * @ro: bitmask of features that force read-only mount | |
1463 | * @incompat: bitmask of incompatible features | |
1464 | * | |
1465 | * Check whether the journaling code supports the use of | |
1466 | * all of a given set of features on this journal. Return true | |
1467 | * (non-zero) if it can. */ | |
1468 | ||
f7f4bccb | 1469 | int jbd2_journal_check_available_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1470 | unsigned long ro, unsigned long incompat) |
1471 | { | |
470decc6 DK |
1472 | if (!compat && !ro && !incompat) |
1473 | return 1; | |
1474 | ||
470decc6 DK |
1475 | /* We can support any known requested features iff the |
1476 | * superblock is in version 2. Otherwise we fail to support any | |
1477 | * extended sb features. */ | |
1478 | ||
1479 | if (journal->j_format_version != 2) | |
1480 | return 0; | |
1481 | ||
f7f4bccb MC |
1482 | if ((compat & JBD2_KNOWN_COMPAT_FEATURES) == compat && |
1483 | (ro & JBD2_KNOWN_ROCOMPAT_FEATURES) == ro && | |
1484 | (incompat & JBD2_KNOWN_INCOMPAT_FEATURES) == incompat) | |
470decc6 DK |
1485 | return 1; |
1486 | ||
1487 | return 0; | |
1488 | } | |
1489 | ||
1490 | /** | |
f7f4bccb | 1491 | * int jbd2_journal_set_features () - Mark a given journal feature in the superblock |
470decc6 DK |
1492 | * @journal: Journal to act on. |
1493 | * @compat: bitmask of compatible features | |
1494 | * @ro: bitmask of features that force read-only mount | |
1495 | * @incompat: bitmask of incompatible features | |
1496 | * | |
1497 | * Mark a given journal feature as present on the | |
1498 | * superblock. Returns true if the requested features could be set. | |
1499 | * | |
1500 | */ | |
1501 | ||
f7f4bccb | 1502 | int jbd2_journal_set_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1503 | unsigned long ro, unsigned long incompat) |
1504 | { | |
1505 | journal_superblock_t *sb; | |
1506 | ||
f7f4bccb | 1507 | if (jbd2_journal_check_used_features(journal, compat, ro, incompat)) |
470decc6 DK |
1508 | return 1; |
1509 | ||
f7f4bccb | 1510 | if (!jbd2_journal_check_available_features(journal, compat, ro, incompat)) |
470decc6 DK |
1511 | return 0; |
1512 | ||
1513 | jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n", | |
1514 | compat, ro, incompat); | |
1515 | ||
1516 | sb = journal->j_superblock; | |
1517 | ||
1518 | sb->s_feature_compat |= cpu_to_be32(compat); | |
1519 | sb->s_feature_ro_compat |= cpu_to_be32(ro); | |
1520 | sb->s_feature_incompat |= cpu_to_be32(incompat); | |
1521 | ||
1522 | return 1; | |
1523 | } | |
1524 | ||
818d276c GS |
1525 | /* |
1526 | * jbd2_journal_clear_features () - Clear a given journal feature in the | |
1527 | * superblock | |
1528 | * @journal: Journal to act on. | |
1529 | * @compat: bitmask of compatible features | |
1530 | * @ro: bitmask of features that force read-only mount | |
1531 | * @incompat: bitmask of incompatible features | |
1532 | * | |
1533 | * Clear a given journal feature as present on the | |
1534 | * superblock. | |
1535 | */ | |
1536 | void jbd2_journal_clear_features(journal_t *journal, unsigned long compat, | |
1537 | unsigned long ro, unsigned long incompat) | |
1538 | { | |
1539 | journal_superblock_t *sb; | |
1540 | ||
1541 | jbd_debug(1, "Clear features 0x%lx/0x%lx/0x%lx\n", | |
1542 | compat, ro, incompat); | |
1543 | ||
1544 | sb = journal->j_superblock; | |
1545 | ||
1546 | sb->s_feature_compat &= ~cpu_to_be32(compat); | |
1547 | sb->s_feature_ro_compat &= ~cpu_to_be32(ro); | |
1548 | sb->s_feature_incompat &= ~cpu_to_be32(incompat); | |
1549 | } | |
1550 | EXPORT_SYMBOL(jbd2_journal_clear_features); | |
470decc6 | 1551 | |
470decc6 | 1552 | /** |
f7f4bccb | 1553 | * int jbd2_journal_flush () - Flush journal |
470decc6 DK |
1554 | * @journal: Journal to act on. |
1555 | * | |
1556 | * Flush all data for a given journal to disk and empty the journal. | |
1557 | * Filesystems can use this when remounting readonly to ensure that | |
1558 | * recovery does not need to happen on remount. | |
1559 | */ | |
1560 | ||
f7f4bccb | 1561 | int jbd2_journal_flush(journal_t *journal) |
470decc6 DK |
1562 | { |
1563 | int err = 0; | |
1564 | transaction_t *transaction = NULL; | |
1565 | unsigned long old_tail; | |
1566 | ||
a931da6a | 1567 | write_lock(&journal->j_state_lock); |
470decc6 DK |
1568 | |
1569 | /* Force everything buffered to the log... */ | |
1570 | if (journal->j_running_transaction) { | |
1571 | transaction = journal->j_running_transaction; | |
f7f4bccb | 1572 | __jbd2_log_start_commit(journal, transaction->t_tid); |
470decc6 DK |
1573 | } else if (journal->j_committing_transaction) |
1574 | transaction = journal->j_committing_transaction; | |
1575 | ||
1576 | /* Wait for the log commit to complete... */ | |
1577 | if (transaction) { | |
1578 | tid_t tid = transaction->t_tid; | |
1579 | ||
a931da6a | 1580 | write_unlock(&journal->j_state_lock); |
f7f4bccb | 1581 | jbd2_log_wait_commit(journal, tid); |
470decc6 | 1582 | } else { |
a931da6a | 1583 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1584 | } |
1585 | ||
1586 | /* ...and flush everything in the log out to disk. */ | |
1587 | spin_lock(&journal->j_list_lock); | |
1588 | while (!err && journal->j_checkpoint_transactions != NULL) { | |
1589 | spin_unlock(&journal->j_list_lock); | |
44519faf | 1590 | mutex_lock(&journal->j_checkpoint_mutex); |
f7f4bccb | 1591 | err = jbd2_log_do_checkpoint(journal); |
44519faf | 1592 | mutex_unlock(&journal->j_checkpoint_mutex); |
470decc6 DK |
1593 | spin_lock(&journal->j_list_lock); |
1594 | } | |
1595 | spin_unlock(&journal->j_list_lock); | |
44519faf HK |
1596 | |
1597 | if (is_journal_aborted(journal)) | |
1598 | return -EIO; | |
1599 | ||
f7f4bccb | 1600 | jbd2_cleanup_journal_tail(journal); |
470decc6 DK |
1601 | |
1602 | /* Finally, mark the journal as really needing no recovery. | |
1603 | * This sets s_start==0 in the underlying superblock, which is | |
1604 | * the magic code for a fully-recovered superblock. Any future | |
1605 | * commits of data to the journal will restore the current | |
1606 | * s_start value. */ | |
a931da6a | 1607 | write_lock(&journal->j_state_lock); |
470decc6 DK |
1608 | old_tail = journal->j_tail; |
1609 | journal->j_tail = 0; | |
a931da6a | 1610 | write_unlock(&journal->j_state_lock); |
f7f4bccb | 1611 | jbd2_journal_update_superblock(journal, 1); |
a931da6a | 1612 | write_lock(&journal->j_state_lock); |
470decc6 DK |
1613 | journal->j_tail = old_tail; |
1614 | ||
1615 | J_ASSERT(!journal->j_running_transaction); | |
1616 | J_ASSERT(!journal->j_committing_transaction); | |
1617 | J_ASSERT(!journal->j_checkpoint_transactions); | |
1618 | J_ASSERT(journal->j_head == journal->j_tail); | |
1619 | J_ASSERT(journal->j_tail_sequence == journal->j_transaction_sequence); | |
a931da6a | 1620 | write_unlock(&journal->j_state_lock); |
44519faf | 1621 | return 0; |
470decc6 DK |
1622 | } |
1623 | ||
1624 | /** | |
f7f4bccb | 1625 | * int jbd2_journal_wipe() - Wipe journal contents |
470decc6 DK |
1626 | * @journal: Journal to act on. |
1627 | * @write: flag (see below) | |
1628 | * | |
1629 | * Wipe out all of the contents of a journal, safely. This will produce | |
1630 | * a warning if the journal contains any valid recovery information. | |
f7f4bccb | 1631 | * Must be called between journal_init_*() and jbd2_journal_load(). |
470decc6 DK |
1632 | * |
1633 | * If 'write' is non-zero, then we wipe out the journal on disk; otherwise | |
1634 | * we merely suppress recovery. | |
1635 | */ | |
1636 | ||
f7f4bccb | 1637 | int jbd2_journal_wipe(journal_t *journal, int write) |
470decc6 | 1638 | { |
470decc6 DK |
1639 | int err = 0; |
1640 | ||
f7f4bccb | 1641 | J_ASSERT (!(journal->j_flags & JBD2_LOADED)); |
470decc6 DK |
1642 | |
1643 | err = load_superblock(journal); | |
1644 | if (err) | |
1645 | return err; | |
1646 | ||
470decc6 DK |
1647 | if (!journal->j_tail) |
1648 | goto no_recovery; | |
1649 | ||
f2a44523 | 1650 | printk(KERN_WARNING "JBD2: %s recovery information on journal\n", |
470decc6 DK |
1651 | write ? "Clearing" : "Ignoring"); |
1652 | ||
f7f4bccb | 1653 | err = jbd2_journal_skip_recovery(journal); |
470decc6 | 1654 | if (write) |
f7f4bccb | 1655 | jbd2_journal_update_superblock(journal, 1); |
470decc6 DK |
1656 | |
1657 | no_recovery: | |
1658 | return err; | |
1659 | } | |
1660 | ||
470decc6 DK |
1661 | /* |
1662 | * Journal abort has very specific semantics, which we describe | |
1663 | * for journal abort. | |
1664 | * | |
bfcd3555 | 1665 | * Two internal functions, which provide abort to the jbd layer |
470decc6 DK |
1666 | * itself are here. |
1667 | */ | |
1668 | ||
1669 | /* | |
1670 | * Quick version for internal journal use (doesn't lock the journal). | |
1671 | * Aborts hard --- we mark the abort as occurred, but do _nothing_ else, | |
1672 | * and don't attempt to make any other journal updates. | |
1673 | */ | |
f7f4bccb | 1674 | void __jbd2_journal_abort_hard(journal_t *journal) |
470decc6 DK |
1675 | { |
1676 | transaction_t *transaction; | |
470decc6 | 1677 | |
f7f4bccb | 1678 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1679 | return; |
1680 | ||
1681 | printk(KERN_ERR "Aborting journal on device %s.\n", | |
05496769 | 1682 | journal->j_devname); |
470decc6 | 1683 | |
a931da6a | 1684 | write_lock(&journal->j_state_lock); |
f7f4bccb | 1685 | journal->j_flags |= JBD2_ABORT; |
470decc6 DK |
1686 | transaction = journal->j_running_transaction; |
1687 | if (transaction) | |
f7f4bccb | 1688 | __jbd2_log_start_commit(journal, transaction->t_tid); |
a931da6a | 1689 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1690 | } |
1691 | ||
1692 | /* Soft abort: record the abort error status in the journal superblock, | |
1693 | * but don't do any other IO. */ | |
1694 | static void __journal_abort_soft (journal_t *journal, int errno) | |
1695 | { | |
f7f4bccb | 1696 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1697 | return; |
1698 | ||
1699 | if (!journal->j_errno) | |
1700 | journal->j_errno = errno; | |
1701 | ||
f7f4bccb | 1702 | __jbd2_journal_abort_hard(journal); |
470decc6 DK |
1703 | |
1704 | if (errno) | |
f7f4bccb | 1705 | jbd2_journal_update_superblock(journal, 1); |
470decc6 DK |
1706 | } |
1707 | ||
1708 | /** | |
f7f4bccb | 1709 | * void jbd2_journal_abort () - Shutdown the journal immediately. |
470decc6 DK |
1710 | * @journal: the journal to shutdown. |
1711 | * @errno: an error number to record in the journal indicating | |
1712 | * the reason for the shutdown. | |
1713 | * | |
1714 | * Perform a complete, immediate shutdown of the ENTIRE | |
1715 | * journal (not of a single transaction). This operation cannot be | |
1716 | * undone without closing and reopening the journal. | |
1717 | * | |
f7f4bccb | 1718 | * The jbd2_journal_abort function is intended to support higher level error |
470decc6 DK |
1719 | * recovery mechanisms such as the ext2/ext3 remount-readonly error |
1720 | * mode. | |
1721 | * | |
1722 | * Journal abort has very specific semantics. Any existing dirty, | |
1723 | * unjournaled buffers in the main filesystem will still be written to | |
1724 | * disk by bdflush, but the journaling mechanism will be suspended | |
1725 | * immediately and no further transaction commits will be honoured. | |
1726 | * | |
1727 | * Any dirty, journaled buffers will be written back to disk without | |
1728 | * hitting the journal. Atomicity cannot be guaranteed on an aborted | |
1729 | * filesystem, but we _do_ attempt to leave as much data as possible | |
1730 | * behind for fsck to use for cleanup. | |
1731 | * | |
1732 | * Any attempt to get a new transaction handle on a journal which is in | |
1733 | * ABORT state will just result in an -EROFS error return. A | |
f7f4bccb | 1734 | * jbd2_journal_stop on an existing handle will return -EIO if we have |
470decc6 DK |
1735 | * entered abort state during the update. |
1736 | * | |
1737 | * Recursive transactions are not disturbed by journal abort until the | |
f7f4bccb | 1738 | * final jbd2_journal_stop, which will receive the -EIO error. |
470decc6 | 1739 | * |
f7f4bccb | 1740 | * Finally, the jbd2_journal_abort call allows the caller to supply an errno |
470decc6 DK |
1741 | * which will be recorded (if possible) in the journal superblock. This |
1742 | * allows a client to record failure conditions in the middle of a | |
1743 | * transaction without having to complete the transaction to record the | |
1744 | * failure to disk. ext3_error, for example, now uses this | |
1745 | * functionality. | |
1746 | * | |
1747 | * Errors which originate from within the journaling layer will NOT | |
1748 | * supply an errno; a null errno implies that absolutely no further | |
1749 | * writes are done to the journal (unless there are any already in | |
1750 | * progress). | |
1751 | * | |
1752 | */ | |
1753 | ||
f7f4bccb | 1754 | void jbd2_journal_abort(journal_t *journal, int errno) |
470decc6 DK |
1755 | { |
1756 | __journal_abort_soft(journal, errno); | |
1757 | } | |
1758 | ||
1759 | /** | |
f7f4bccb | 1760 | * int jbd2_journal_errno () - returns the journal's error state. |
470decc6 DK |
1761 | * @journal: journal to examine. |
1762 | * | |
bfcd3555 | 1763 | * This is the errno number set with jbd2_journal_abort(), the last |
470decc6 DK |
1764 | * time the journal was mounted - if the journal was stopped |
1765 | * without calling abort this will be 0. | |
1766 | * | |
1767 | * If the journal has been aborted on this mount time -EROFS will | |
1768 | * be returned. | |
1769 | */ | |
f7f4bccb | 1770 | int jbd2_journal_errno(journal_t *journal) |
470decc6 DK |
1771 | { |
1772 | int err; | |
1773 | ||
a931da6a | 1774 | read_lock(&journal->j_state_lock); |
f7f4bccb | 1775 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1776 | err = -EROFS; |
1777 | else | |
1778 | err = journal->j_errno; | |
a931da6a | 1779 | read_unlock(&journal->j_state_lock); |
470decc6 DK |
1780 | return err; |
1781 | } | |
1782 | ||
1783 | /** | |
f7f4bccb | 1784 | * int jbd2_journal_clear_err () - clears the journal's error state |
470decc6 DK |
1785 | * @journal: journal to act on. |
1786 | * | |
bfcd3555 | 1787 | * An error must be cleared or acked to take a FS out of readonly |
470decc6 DK |
1788 | * mode. |
1789 | */ | |
f7f4bccb | 1790 | int jbd2_journal_clear_err(journal_t *journal) |
470decc6 DK |
1791 | { |
1792 | int err = 0; | |
1793 | ||
a931da6a | 1794 | write_lock(&journal->j_state_lock); |
f7f4bccb | 1795 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
1796 | err = -EROFS; |
1797 | else | |
1798 | journal->j_errno = 0; | |
a931da6a | 1799 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1800 | return err; |
1801 | } | |
1802 | ||
1803 | /** | |
f7f4bccb | 1804 | * void jbd2_journal_ack_err() - Ack journal err. |
470decc6 DK |
1805 | * @journal: journal to act on. |
1806 | * | |
bfcd3555 | 1807 | * An error must be cleared or acked to take a FS out of readonly |
470decc6 DK |
1808 | * mode. |
1809 | */ | |
f7f4bccb | 1810 | void jbd2_journal_ack_err(journal_t *journal) |
470decc6 | 1811 | { |
a931da6a | 1812 | write_lock(&journal->j_state_lock); |
470decc6 | 1813 | if (journal->j_errno) |
f7f4bccb | 1814 | journal->j_flags |= JBD2_ACK_ERR; |
a931da6a | 1815 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1816 | } |
1817 | ||
f7f4bccb | 1818 | int jbd2_journal_blocks_per_page(struct inode *inode) |
470decc6 DK |
1819 | { |
1820 | return 1 << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
1821 | } | |
1822 | ||
b517bea1 ZB |
1823 | /* |
1824 | * helper functions to deal with 32 or 64bit block numbers. | |
1825 | */ | |
1826 | size_t journal_tag_bytes(journal_t *journal) | |
1827 | { | |
1828 | if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_64BIT)) | |
cd02ff0b | 1829 | return JBD2_TAG_SIZE64; |
b517bea1 | 1830 | else |
cd02ff0b | 1831 | return JBD2_TAG_SIZE32; |
b517bea1 ZB |
1832 | } |
1833 | ||
d2eecb03 TT |
1834 | /* |
1835 | * JBD memory management | |
1836 | * | |
1837 | * These functions are used to allocate block-sized chunks of memory | |
1838 | * used for making copies of buffer_head data. Very often it will be | |
1839 | * page-sized chunks of data, but sometimes it will be in | |
1840 | * sub-page-size chunks. (For example, 16k pages on Power systems | |
1841 | * with a 4k block file system.) For blocks smaller than a page, we | |
1842 | * use a SLAB allocator. There are slab caches for each block size, | |
1843 | * which are allocated at mount time, if necessary, and we only free | |
1844 | * (all of) the slab caches when/if the jbd2 module is unloaded. For | |
1845 | * this reason we don't need to a mutex to protect access to | |
1846 | * jbd2_slab[] allocating or releasing memory; only in | |
1847 | * jbd2_journal_create_slab(). | |
1848 | */ | |
1849 | #define JBD2_MAX_SLABS 8 | |
1850 | static struct kmem_cache *jbd2_slab[JBD2_MAX_SLABS]; | |
d2eecb03 TT |
1851 | |
1852 | static const char *jbd2_slab_names[JBD2_MAX_SLABS] = { | |
1853 | "jbd2_1k", "jbd2_2k", "jbd2_4k", "jbd2_8k", | |
1854 | "jbd2_16k", "jbd2_32k", "jbd2_64k", "jbd2_128k" | |
1855 | }; | |
1856 | ||
1857 | ||
1858 | static void jbd2_journal_destroy_slabs(void) | |
1859 | { | |
1860 | int i; | |
1861 | ||
1862 | for (i = 0; i < JBD2_MAX_SLABS; i++) { | |
1863 | if (jbd2_slab[i]) | |
1864 | kmem_cache_destroy(jbd2_slab[i]); | |
1865 | jbd2_slab[i] = NULL; | |
1866 | } | |
1867 | } | |
1868 | ||
1869 | static int jbd2_journal_create_slab(size_t size) | |
1870 | { | |
51dfacde | 1871 | static DEFINE_MUTEX(jbd2_slab_create_mutex); |
d2eecb03 TT |
1872 | int i = order_base_2(size) - 10; |
1873 | size_t slab_size; | |
1874 | ||
1875 | if (size == PAGE_SIZE) | |
1876 | return 0; | |
1877 | ||
1878 | if (i >= JBD2_MAX_SLABS) | |
1879 | return -EINVAL; | |
1880 | ||
1881 | if (unlikely(i < 0)) | |
1882 | i = 0; | |
51dfacde | 1883 | mutex_lock(&jbd2_slab_create_mutex); |
d2eecb03 | 1884 | if (jbd2_slab[i]) { |
51dfacde | 1885 | mutex_unlock(&jbd2_slab_create_mutex); |
d2eecb03 TT |
1886 | return 0; /* Already created */ |
1887 | } | |
1888 | ||
1889 | slab_size = 1 << (i+10); | |
1890 | jbd2_slab[i] = kmem_cache_create(jbd2_slab_names[i], slab_size, | |
1891 | slab_size, 0, NULL); | |
51dfacde | 1892 | mutex_unlock(&jbd2_slab_create_mutex); |
d2eecb03 TT |
1893 | if (!jbd2_slab[i]) { |
1894 | printk(KERN_EMERG "JBD2: no memory for jbd2_slab cache\n"); | |
1895 | return -ENOMEM; | |
1896 | } | |
1897 | return 0; | |
1898 | } | |
1899 | ||
1900 | static struct kmem_cache *get_slab(size_t size) | |
1901 | { | |
1902 | int i = order_base_2(size) - 10; | |
1903 | ||
1904 | BUG_ON(i >= JBD2_MAX_SLABS); | |
1905 | if (unlikely(i < 0)) | |
1906 | i = 0; | |
8ac97b74 | 1907 | BUG_ON(jbd2_slab[i] == NULL); |
d2eecb03 TT |
1908 | return jbd2_slab[i]; |
1909 | } | |
1910 | ||
1911 | void *jbd2_alloc(size_t size, gfp_t flags) | |
1912 | { | |
1913 | void *ptr; | |
1914 | ||
1915 | BUG_ON(size & (size-1)); /* Must be a power of 2 */ | |
1916 | ||
1917 | flags |= __GFP_REPEAT; | |
1918 | if (size == PAGE_SIZE) | |
1919 | ptr = (void *)__get_free_pages(flags, 0); | |
1920 | else if (size > PAGE_SIZE) { | |
1921 | int order = get_order(size); | |
1922 | ||
1923 | if (order < 3) | |
1924 | ptr = (void *)__get_free_pages(flags, order); | |
1925 | else | |
1926 | ptr = vmalloc(size); | |
1927 | } else | |
1928 | ptr = kmem_cache_alloc(get_slab(size), flags); | |
1929 | ||
1930 | /* Check alignment; SLUB has gotten this wrong in the past, | |
1931 | * and this can lead to user data corruption! */ | |
1932 | BUG_ON(((unsigned long) ptr) & (size-1)); | |
1933 | ||
1934 | return ptr; | |
1935 | } | |
1936 | ||
1937 | void jbd2_free(void *ptr, size_t size) | |
1938 | { | |
1939 | if (size == PAGE_SIZE) { | |
1940 | free_pages((unsigned long)ptr, 0); | |
1941 | return; | |
1942 | } | |
1943 | if (size > PAGE_SIZE) { | |
1944 | int order = get_order(size); | |
1945 | ||
1946 | if (order < 3) | |
1947 | free_pages((unsigned long)ptr, order); | |
1948 | else | |
1949 | vfree(ptr); | |
1950 | return; | |
1951 | } | |
1952 | kmem_cache_free(get_slab(size), ptr); | |
1953 | }; | |
1954 | ||
470decc6 DK |
1955 | /* |
1956 | * Journal_head storage management | |
1957 | */ | |
e18b890b | 1958 | static struct kmem_cache *jbd2_journal_head_cache; |
e23291b9 | 1959 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
1960 | static atomic_t nr_journal_heads = ATOMIC_INIT(0); |
1961 | #endif | |
1962 | ||
4185a2ac | 1963 | static int jbd2_journal_init_journal_head_cache(void) |
470decc6 DK |
1964 | { |
1965 | int retval; | |
1966 | ||
1076d17a | 1967 | J_ASSERT(jbd2_journal_head_cache == NULL); |
a920e941 | 1968 | jbd2_journal_head_cache = kmem_cache_create("jbd2_journal_head", |
470decc6 DK |
1969 | sizeof(struct journal_head), |
1970 | 0, /* offset */ | |
77160957 | 1971 | SLAB_TEMPORARY, /* flags */ |
20c2df83 | 1972 | NULL); /* ctor */ |
470decc6 | 1973 | retval = 0; |
1076d17a | 1974 | if (!jbd2_journal_head_cache) { |
470decc6 | 1975 | retval = -ENOMEM; |
f2a44523 | 1976 | printk(KERN_EMERG "JBD2: no memory for journal_head cache\n"); |
470decc6 DK |
1977 | } |
1978 | return retval; | |
1979 | } | |
1980 | ||
4185a2ac | 1981 | static void jbd2_journal_destroy_journal_head_cache(void) |
470decc6 | 1982 | { |
8a9362eb DG |
1983 | if (jbd2_journal_head_cache) { |
1984 | kmem_cache_destroy(jbd2_journal_head_cache); | |
1985 | jbd2_journal_head_cache = NULL; | |
1986 | } | |
470decc6 DK |
1987 | } |
1988 | ||
1989 | /* | |
1990 | * journal_head splicing and dicing | |
1991 | */ | |
1992 | static struct journal_head *journal_alloc_journal_head(void) | |
1993 | { | |
1994 | struct journal_head *ret; | |
470decc6 | 1995 | |
e23291b9 | 1996 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
1997 | atomic_inc(&nr_journal_heads); |
1998 | #endif | |
f7f4bccb | 1999 | ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS); |
1076d17a | 2000 | if (!ret) { |
470decc6 | 2001 | jbd_debug(1, "out of memory for journal_head\n"); |
670be5a7 | 2002 | pr_notice_ratelimited("ENOMEM in %s, retrying.\n", __func__); |
1076d17a | 2003 | while (!ret) { |
470decc6 | 2004 | yield(); |
f7f4bccb | 2005 | ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS); |
470decc6 DK |
2006 | } |
2007 | } | |
2008 | return ret; | |
2009 | } | |
2010 | ||
2011 | static void journal_free_journal_head(struct journal_head *jh) | |
2012 | { | |
e23291b9 | 2013 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 | 2014 | atomic_dec(&nr_journal_heads); |
cd02ff0b | 2015 | memset(jh, JBD2_POISON_FREE, sizeof(*jh)); |
470decc6 | 2016 | #endif |
f7f4bccb | 2017 | kmem_cache_free(jbd2_journal_head_cache, jh); |
470decc6 DK |
2018 | } |
2019 | ||
2020 | /* | |
2021 | * A journal_head is attached to a buffer_head whenever JBD has an | |
2022 | * interest in the buffer. | |
2023 | * | |
2024 | * Whenever a buffer has an attached journal_head, its ->b_state:BH_JBD bit | |
2025 | * is set. This bit is tested in core kernel code where we need to take | |
2026 | * JBD-specific actions. Testing the zeroness of ->b_private is not reliable | |
2027 | * there. | |
2028 | * | |
2029 | * When a buffer has its BH_JBD bit set, its ->b_count is elevated by one. | |
2030 | * | |
2031 | * When a buffer has its BH_JBD bit set it is immune from being released by | |
2032 | * core kernel code, mainly via ->b_count. | |
2033 | * | |
de1b7941 JK |
2034 | * A journal_head is detached from its buffer_head when the journal_head's |
2035 | * b_jcount reaches zero. Running transaction (b_transaction) and checkpoint | |
2036 | * transaction (b_cp_transaction) hold their references to b_jcount. | |
470decc6 DK |
2037 | * |
2038 | * Various places in the kernel want to attach a journal_head to a buffer_head | |
2039 | * _before_ attaching the journal_head to a transaction. To protect the | |
f7f4bccb | 2040 | * journal_head in this situation, jbd2_journal_add_journal_head elevates the |
470decc6 | 2041 | * journal_head's b_jcount refcount by one. The caller must call |
f7f4bccb | 2042 | * jbd2_journal_put_journal_head() to undo this. |
470decc6 DK |
2043 | * |
2044 | * So the typical usage would be: | |
2045 | * | |
2046 | * (Attach a journal_head if needed. Increments b_jcount) | |
f7f4bccb | 2047 | * struct journal_head *jh = jbd2_journal_add_journal_head(bh); |
470decc6 | 2048 | * ... |
de1b7941 JK |
2049 | * (Get another reference for transaction) |
2050 | * jbd2_journal_grab_journal_head(bh); | |
470decc6 | 2051 | * jh->b_transaction = xxx; |
de1b7941 | 2052 | * (Put original reference) |
f7f4bccb | 2053 | * jbd2_journal_put_journal_head(jh); |
470decc6 DK |
2054 | */ |
2055 | ||
2056 | /* | |
2057 | * Give a buffer_head a journal_head. | |
2058 | * | |
470decc6 DK |
2059 | * May sleep. |
2060 | */ | |
f7f4bccb | 2061 | struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh) |
470decc6 DK |
2062 | { |
2063 | struct journal_head *jh; | |
2064 | struct journal_head *new_jh = NULL; | |
2065 | ||
2066 | repeat: | |
2067 | if (!buffer_jbd(bh)) { | |
2068 | new_jh = journal_alloc_journal_head(); | |
2069 | memset(new_jh, 0, sizeof(*new_jh)); | |
2070 | } | |
2071 | ||
2072 | jbd_lock_bh_journal_head(bh); | |
2073 | if (buffer_jbd(bh)) { | |
2074 | jh = bh2jh(bh); | |
2075 | } else { | |
2076 | J_ASSERT_BH(bh, | |
2077 | (atomic_read(&bh->b_count) > 0) || | |
2078 | (bh->b_page && bh->b_page->mapping)); | |
2079 | ||
2080 | if (!new_jh) { | |
2081 | jbd_unlock_bh_journal_head(bh); | |
2082 | goto repeat; | |
2083 | } | |
2084 | ||
2085 | jh = new_jh; | |
2086 | new_jh = NULL; /* We consumed it */ | |
2087 | set_buffer_jbd(bh); | |
2088 | bh->b_private = jh; | |
2089 | jh->b_bh = bh; | |
2090 | get_bh(bh); | |
2091 | BUFFER_TRACE(bh, "added journal_head"); | |
2092 | } | |
2093 | jh->b_jcount++; | |
2094 | jbd_unlock_bh_journal_head(bh); | |
2095 | if (new_jh) | |
2096 | journal_free_journal_head(new_jh); | |
2097 | return bh->b_private; | |
2098 | } | |
2099 | ||
2100 | /* | |
2101 | * Grab a ref against this buffer_head's journal_head. If it ended up not | |
2102 | * having a journal_head, return NULL | |
2103 | */ | |
f7f4bccb | 2104 | struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh) |
470decc6 DK |
2105 | { |
2106 | struct journal_head *jh = NULL; | |
2107 | ||
2108 | jbd_lock_bh_journal_head(bh); | |
2109 | if (buffer_jbd(bh)) { | |
2110 | jh = bh2jh(bh); | |
2111 | jh->b_jcount++; | |
2112 | } | |
2113 | jbd_unlock_bh_journal_head(bh); | |
2114 | return jh; | |
2115 | } | |
2116 | ||
2117 | static void __journal_remove_journal_head(struct buffer_head *bh) | |
2118 | { | |
2119 | struct journal_head *jh = bh2jh(bh); | |
2120 | ||
2121 | J_ASSERT_JH(jh, jh->b_jcount >= 0); | |
de1b7941 JK |
2122 | J_ASSERT_JH(jh, jh->b_transaction == NULL); |
2123 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); | |
2124 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); | |
2125 | J_ASSERT_JH(jh, jh->b_jlist == BJ_None); | |
2126 | J_ASSERT_BH(bh, buffer_jbd(bh)); | |
2127 | J_ASSERT_BH(bh, jh2bh(jh) == bh); | |
2128 | BUFFER_TRACE(bh, "remove journal_head"); | |
2129 | if (jh->b_frozen_data) { | |
2130 | printk(KERN_WARNING "%s: freeing b_frozen_data\n", __func__); | |
2131 | jbd2_free(jh->b_frozen_data, bh->b_size); | |
470decc6 | 2132 | } |
de1b7941 JK |
2133 | if (jh->b_committed_data) { |
2134 | printk(KERN_WARNING "%s: freeing b_committed_data\n", __func__); | |
2135 | jbd2_free(jh->b_committed_data, bh->b_size); | |
2136 | } | |
2137 | bh->b_private = NULL; | |
2138 | jh->b_bh = NULL; /* debug, really */ | |
2139 | clear_buffer_jbd(bh); | |
2140 | journal_free_journal_head(jh); | |
470decc6 DK |
2141 | } |
2142 | ||
2143 | /* | |
de1b7941 | 2144 | * Drop a reference on the passed journal_head. If it fell to zero then |
470decc6 DK |
2145 | * release the journal_head from the buffer_head. |
2146 | */ | |
f7f4bccb | 2147 | void jbd2_journal_put_journal_head(struct journal_head *jh) |
470decc6 DK |
2148 | { |
2149 | struct buffer_head *bh = jh2bh(jh); | |
2150 | ||
2151 | jbd_lock_bh_journal_head(bh); | |
2152 | J_ASSERT_JH(jh, jh->b_jcount > 0); | |
2153 | --jh->b_jcount; | |
de1b7941 | 2154 | if (!jh->b_jcount) { |
470decc6 | 2155 | __journal_remove_journal_head(bh); |
de1b7941 | 2156 | jbd_unlock_bh_journal_head(bh); |
470decc6 | 2157 | __brelse(bh); |
de1b7941 JK |
2158 | } else |
2159 | jbd_unlock_bh_journal_head(bh); | |
470decc6 DK |
2160 | } |
2161 | ||
c851ed54 JK |
2162 | /* |
2163 | * Initialize jbd inode head | |
2164 | */ | |
2165 | void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode) | |
2166 | { | |
2167 | jinode->i_transaction = NULL; | |
2168 | jinode->i_next_transaction = NULL; | |
2169 | jinode->i_vfs_inode = inode; | |
2170 | jinode->i_flags = 0; | |
2171 | INIT_LIST_HEAD(&jinode->i_list); | |
2172 | } | |
2173 | ||
2174 | /* | |
2175 | * Function to be called before we start removing inode from memory (i.e., | |
2176 | * clear_inode() is a fine place to be called from). It removes inode from | |
2177 | * transaction's lists. | |
2178 | */ | |
2179 | void jbd2_journal_release_jbd_inode(journal_t *journal, | |
2180 | struct jbd2_inode *jinode) | |
2181 | { | |
c851ed54 JK |
2182 | if (!journal) |
2183 | return; | |
2184 | restart: | |
2185 | spin_lock(&journal->j_list_lock); | |
2186 | /* Is commit writing out inode - we have to wait */ | |
39e3ac25 | 2187 | if (test_bit(__JI_COMMIT_RUNNING, &jinode->i_flags)) { |
c851ed54 JK |
2188 | wait_queue_head_t *wq; |
2189 | DEFINE_WAIT_BIT(wait, &jinode->i_flags, __JI_COMMIT_RUNNING); | |
2190 | wq = bit_waitqueue(&jinode->i_flags, __JI_COMMIT_RUNNING); | |
2191 | prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE); | |
2192 | spin_unlock(&journal->j_list_lock); | |
2193 | schedule(); | |
2194 | finish_wait(wq, &wait.wait); | |
2195 | goto restart; | |
2196 | } | |
2197 | ||
c851ed54 JK |
2198 | if (jinode->i_transaction) { |
2199 | list_del(&jinode->i_list); | |
2200 | jinode->i_transaction = NULL; | |
2201 | } | |
2202 | spin_unlock(&journal->j_list_lock); | |
2203 | } | |
2204 | ||
470decc6 | 2205 | /* |
0f49d5d0 | 2206 | * debugfs tunables |
470decc6 | 2207 | */ |
6f38c74f JS |
2208 | #ifdef CONFIG_JBD2_DEBUG |
2209 | u8 jbd2_journal_enable_debug __read_mostly; | |
f7f4bccb | 2210 | EXPORT_SYMBOL(jbd2_journal_enable_debug); |
470decc6 | 2211 | |
0f49d5d0 | 2212 | #define JBD2_DEBUG_NAME "jbd2-debug" |
470decc6 | 2213 | |
6f38c74f JS |
2214 | static struct dentry *jbd2_debugfs_dir; |
2215 | static struct dentry *jbd2_debug; | |
470decc6 | 2216 | |
0f49d5d0 JS |
2217 | static void __init jbd2_create_debugfs_entry(void) |
2218 | { | |
2219 | jbd2_debugfs_dir = debugfs_create_dir("jbd2", NULL); | |
2220 | if (jbd2_debugfs_dir) | |
765f8361 YK |
2221 | jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME, |
2222 | S_IRUGO | S_IWUSR, | |
0f49d5d0 JS |
2223 | jbd2_debugfs_dir, |
2224 | &jbd2_journal_enable_debug); | |
470decc6 DK |
2225 | } |
2226 | ||
0f49d5d0 | 2227 | static void __exit jbd2_remove_debugfs_entry(void) |
470decc6 | 2228 | { |
6f38c74f JS |
2229 | debugfs_remove(jbd2_debug); |
2230 | debugfs_remove(jbd2_debugfs_dir); | |
470decc6 DK |
2231 | } |
2232 | ||
0f49d5d0 | 2233 | #else |
470decc6 | 2234 | |
0f49d5d0 | 2235 | static void __init jbd2_create_debugfs_entry(void) |
470decc6 | 2236 | { |
470decc6 DK |
2237 | } |
2238 | ||
0f49d5d0 | 2239 | static void __exit jbd2_remove_debugfs_entry(void) |
470decc6 | 2240 | { |
470decc6 DK |
2241 | } |
2242 | ||
470decc6 DK |
2243 | #endif |
2244 | ||
8e85fb3f JL |
2245 | #ifdef CONFIG_PROC_FS |
2246 | ||
2247 | #define JBD2_STATS_PROC_NAME "fs/jbd2" | |
2248 | ||
2249 | static void __init jbd2_create_jbd_stats_proc_entry(void) | |
2250 | { | |
2251 | proc_jbd2_stats = proc_mkdir(JBD2_STATS_PROC_NAME, NULL); | |
2252 | } | |
2253 | ||
2254 | static void __exit jbd2_remove_jbd_stats_proc_entry(void) | |
2255 | { | |
2256 | if (proc_jbd2_stats) | |
2257 | remove_proc_entry(JBD2_STATS_PROC_NAME, NULL); | |
2258 | } | |
2259 | ||
2260 | #else | |
2261 | ||
2262 | #define jbd2_create_jbd_stats_proc_entry() do {} while (0) | |
2263 | #define jbd2_remove_jbd_stats_proc_entry() do {} while (0) | |
2264 | ||
2265 | #endif | |
2266 | ||
8aefcd55 | 2267 | struct kmem_cache *jbd2_handle_cache, *jbd2_inode_cache; |
470decc6 | 2268 | |
4185a2ac | 2269 | static int __init jbd2_journal_init_handle_cache(void) |
470decc6 | 2270 | { |
8aefcd55 | 2271 | jbd2_handle_cache = KMEM_CACHE(jbd2_journal_handle, SLAB_TEMPORARY); |
f7f4bccb | 2272 | if (jbd2_handle_cache == NULL) { |
8aefcd55 TT |
2273 | printk(KERN_EMERG "JBD2: failed to create handle cache\n"); |
2274 | return -ENOMEM; | |
2275 | } | |
2276 | jbd2_inode_cache = KMEM_CACHE(jbd2_inode, 0); | |
2277 | if (jbd2_inode_cache == NULL) { | |
2278 | printk(KERN_EMERG "JBD2: failed to create inode cache\n"); | |
2279 | kmem_cache_destroy(jbd2_handle_cache); | |
470decc6 DK |
2280 | return -ENOMEM; |
2281 | } | |
2282 | return 0; | |
2283 | } | |
2284 | ||
f7f4bccb | 2285 | static void jbd2_journal_destroy_handle_cache(void) |
470decc6 | 2286 | { |
f7f4bccb MC |
2287 | if (jbd2_handle_cache) |
2288 | kmem_cache_destroy(jbd2_handle_cache); | |
8aefcd55 TT |
2289 | if (jbd2_inode_cache) |
2290 | kmem_cache_destroy(jbd2_inode_cache); | |
2291 | ||
470decc6 DK |
2292 | } |
2293 | ||
2294 | /* | |
2295 | * Module startup and shutdown | |
2296 | */ | |
2297 | ||
2298 | static int __init journal_init_caches(void) | |
2299 | { | |
2300 | int ret; | |
2301 | ||
f7f4bccb | 2302 | ret = jbd2_journal_init_revoke_caches(); |
470decc6 | 2303 | if (ret == 0) |
4185a2ac | 2304 | ret = jbd2_journal_init_journal_head_cache(); |
470decc6 | 2305 | if (ret == 0) |
4185a2ac | 2306 | ret = jbd2_journal_init_handle_cache(); |
0c2022ec YY |
2307 | if (ret == 0) |
2308 | ret = jbd2_journal_init_transaction_cache(); | |
470decc6 DK |
2309 | return ret; |
2310 | } | |
2311 | ||
f7f4bccb | 2312 | static void jbd2_journal_destroy_caches(void) |
470decc6 | 2313 | { |
f7f4bccb | 2314 | jbd2_journal_destroy_revoke_caches(); |
4185a2ac | 2315 | jbd2_journal_destroy_journal_head_cache(); |
f7f4bccb | 2316 | jbd2_journal_destroy_handle_cache(); |
0c2022ec | 2317 | jbd2_journal_destroy_transaction_cache(); |
d2eecb03 | 2318 | jbd2_journal_destroy_slabs(); |
470decc6 DK |
2319 | } |
2320 | ||
2321 | static int __init journal_init(void) | |
2322 | { | |
2323 | int ret; | |
2324 | ||
2325 | BUILD_BUG_ON(sizeof(struct journal_superblock_s) != 1024); | |
2326 | ||
2327 | ret = journal_init_caches(); | |
620de4e1 DG |
2328 | if (ret == 0) { |
2329 | jbd2_create_debugfs_entry(); | |
2330 | jbd2_create_jbd_stats_proc_entry(); | |
2331 | } else { | |
f7f4bccb | 2332 | jbd2_journal_destroy_caches(); |
620de4e1 | 2333 | } |
470decc6 DK |
2334 | return ret; |
2335 | } | |
2336 | ||
2337 | static void __exit journal_exit(void) | |
2338 | { | |
e23291b9 | 2339 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
2340 | int n = atomic_read(&nr_journal_heads); |
2341 | if (n) | |
f2a44523 | 2342 | printk(KERN_EMERG "JBD2: leaked %d journal_heads!\n", n); |
470decc6 | 2343 | #endif |
0f49d5d0 | 2344 | jbd2_remove_debugfs_entry(); |
8e85fb3f | 2345 | jbd2_remove_jbd_stats_proc_entry(); |
f7f4bccb | 2346 | jbd2_journal_destroy_caches(); |
470decc6 DK |
2347 | } |
2348 | ||
2349 | MODULE_LICENSE("GPL"); | |
2350 | module_init(journal_init); | |
2351 | module_exit(journal_exit); | |
2352 |