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> | |
8e85fb3f | 38 | #include <linux/seq_file.h> |
c225aa57 | 39 | #include <linux/math64.h> |
879c5e6b | 40 | #include <linux/hash.h> |
d2eecb03 TT |
41 | #include <linux/log2.h> |
42 | #include <linux/vmalloc.h> | |
47def826 | 43 | #include <linux/backing-dev.h> |
39e3ac25 | 44 | #include <linux/bitops.h> |
670be5a7 | 45 | #include <linux/ratelimit.h> |
879c5e6b TT |
46 | |
47 | #define CREATE_TRACE_POINTS | |
48 | #include <trace/events/jbd2.h> | |
470decc6 DK |
49 | |
50 | #include <asm/uaccess.h> | |
51 | #include <asm/page.h> | |
52 | ||
b6e96d00 TT |
53 | #ifdef CONFIG_JBD2_DEBUG |
54 | ushort jbd2_journal_enable_debug __read_mostly; | |
55 | EXPORT_SYMBOL(jbd2_journal_enable_debug); | |
56 | ||
57 | module_param_named(jbd2_debug, jbd2_journal_enable_debug, ushort, 0644); | |
58 | MODULE_PARM_DESC(jbd2_debug, "Debugging level for jbd2"); | |
59 | #endif | |
60 | ||
f7f4bccb MC |
61 | EXPORT_SYMBOL(jbd2_journal_extend); |
62 | EXPORT_SYMBOL(jbd2_journal_stop); | |
63 | EXPORT_SYMBOL(jbd2_journal_lock_updates); | |
64 | EXPORT_SYMBOL(jbd2_journal_unlock_updates); | |
65 | EXPORT_SYMBOL(jbd2_journal_get_write_access); | |
66 | EXPORT_SYMBOL(jbd2_journal_get_create_access); | |
67 | EXPORT_SYMBOL(jbd2_journal_get_undo_access); | |
e06c8227 | 68 | EXPORT_SYMBOL(jbd2_journal_set_triggers); |
f7f4bccb | 69 | EXPORT_SYMBOL(jbd2_journal_dirty_metadata); |
f7f4bccb | 70 | EXPORT_SYMBOL(jbd2_journal_forget); |
470decc6 DK |
71 | #if 0 |
72 | EXPORT_SYMBOL(journal_sync_buffer); | |
73 | #endif | |
f7f4bccb MC |
74 | EXPORT_SYMBOL(jbd2_journal_flush); |
75 | EXPORT_SYMBOL(jbd2_journal_revoke); | |
76 | ||
77 | EXPORT_SYMBOL(jbd2_journal_init_dev); | |
78 | EXPORT_SYMBOL(jbd2_journal_init_inode); | |
f7f4bccb MC |
79 | EXPORT_SYMBOL(jbd2_journal_check_used_features); |
80 | EXPORT_SYMBOL(jbd2_journal_check_available_features); | |
81 | EXPORT_SYMBOL(jbd2_journal_set_features); | |
f7f4bccb MC |
82 | EXPORT_SYMBOL(jbd2_journal_load); |
83 | EXPORT_SYMBOL(jbd2_journal_destroy); | |
f7f4bccb MC |
84 | EXPORT_SYMBOL(jbd2_journal_abort); |
85 | EXPORT_SYMBOL(jbd2_journal_errno); | |
86 | EXPORT_SYMBOL(jbd2_journal_ack_err); | |
87 | EXPORT_SYMBOL(jbd2_journal_clear_err); | |
88 | EXPORT_SYMBOL(jbd2_log_wait_commit); | |
3b799d15 | 89 | EXPORT_SYMBOL(jbd2_log_start_commit); |
f7f4bccb MC |
90 | EXPORT_SYMBOL(jbd2_journal_start_commit); |
91 | EXPORT_SYMBOL(jbd2_journal_force_commit_nested); | |
92 | EXPORT_SYMBOL(jbd2_journal_wipe); | |
93 | EXPORT_SYMBOL(jbd2_journal_blocks_per_page); | |
94 | EXPORT_SYMBOL(jbd2_journal_invalidatepage); | |
95 | EXPORT_SYMBOL(jbd2_journal_try_to_free_buffers); | |
96 | EXPORT_SYMBOL(jbd2_journal_force_commit); | |
c851ed54 JK |
97 | EXPORT_SYMBOL(jbd2_journal_file_inode); |
98 | EXPORT_SYMBOL(jbd2_journal_init_jbd_inode); | |
99 | EXPORT_SYMBOL(jbd2_journal_release_jbd_inode); | |
100 | EXPORT_SYMBOL(jbd2_journal_begin_ordered_truncate); | |
8aefcd55 | 101 | EXPORT_SYMBOL(jbd2_inode_cache); |
470decc6 | 102 | |
470decc6 | 103 | static void __journal_abort_soft (journal_t *journal, int errno); |
d2eecb03 | 104 | static int jbd2_journal_create_slab(size_t slab_size); |
470decc6 | 105 | |
169f1a2a PG |
106 | #ifdef CONFIG_JBD2_DEBUG |
107 | void __jbd2_debug(int level, const char *file, const char *func, | |
108 | unsigned int line, const char *fmt, ...) | |
109 | { | |
110 | struct va_format vaf; | |
111 | va_list args; | |
112 | ||
113 | if (level > jbd2_journal_enable_debug) | |
114 | return; | |
115 | va_start(args, fmt); | |
116 | vaf.fmt = fmt; | |
117 | vaf.va = &args; | |
118 | printk(KERN_DEBUG "%s: (%s, %u): %pV\n", file, func, line, &vaf); | |
119 | va_end(args); | |
120 | } | |
121 | EXPORT_SYMBOL(__jbd2_debug); | |
122 | #endif | |
123 | ||
25ed6e8a | 124 | /* Checksumming functions */ |
7747e6d0 | 125 | static int jbd2_verify_csum_type(journal_t *j, journal_superblock_t *sb) |
25ed6e8a | 126 | { |
8595798c | 127 | if (!jbd2_journal_has_csum_v2or3_feature(j)) |
25ed6e8a DW |
128 | return 1; |
129 | ||
130 | return sb->s_checksum_type == JBD2_CRC32C_CHKSUM; | |
131 | } | |
132 | ||
18a6ea1e | 133 | static __be32 jbd2_superblock_csum(journal_t *j, journal_superblock_t *sb) |
4fd5ea43 | 134 | { |
18a6ea1e DW |
135 | __u32 csum; |
136 | __be32 old_csum; | |
4fd5ea43 DW |
137 | |
138 | old_csum = sb->s_checksum; | |
139 | sb->s_checksum = 0; | |
140 | csum = jbd2_chksum(j, ~0, (char *)sb, sizeof(journal_superblock_t)); | |
141 | sb->s_checksum = old_csum; | |
142 | ||
143 | return cpu_to_be32(csum); | |
144 | } | |
145 | ||
7747e6d0 | 146 | static int jbd2_superblock_csum_verify(journal_t *j, journal_superblock_t *sb) |
4fd5ea43 | 147 | { |
db9ee220 | 148 | if (!jbd2_journal_has_csum_v2or3(j)) |
4fd5ea43 DW |
149 | return 1; |
150 | ||
151 | return sb->s_checksum == jbd2_superblock_csum(j, sb); | |
152 | } | |
153 | ||
7747e6d0 | 154 | static void jbd2_superblock_csum_set(journal_t *j, journal_superblock_t *sb) |
4fd5ea43 | 155 | { |
db9ee220 | 156 | if (!jbd2_journal_has_csum_v2or3(j)) |
4fd5ea43 DW |
157 | return; |
158 | ||
159 | sb->s_checksum = jbd2_superblock_csum(j, sb); | |
160 | } | |
161 | ||
470decc6 DK |
162 | /* |
163 | * Helper function used to manage commit timeouts | |
164 | */ | |
165 | ||
166 | static void commit_timeout(unsigned long __data) | |
167 | { | |
168 | struct task_struct * p = (struct task_struct *) __data; | |
169 | ||
170 | wake_up_process(p); | |
171 | } | |
172 | ||
173 | /* | |
f7f4bccb | 174 | * kjournald2: The main thread function used to manage a logging device |
470decc6 DK |
175 | * journal. |
176 | * | |
177 | * This kernel thread is responsible for two things: | |
178 | * | |
179 | * 1) COMMIT: Every so often we need to commit the current state of the | |
180 | * filesystem to disk. The journal thread is responsible for writing | |
181 | * all of the metadata buffers to disk. | |
182 | * | |
183 | * 2) CHECKPOINT: We cannot reuse a used section of the log file until all | |
184 | * of the data in that part of the log has been rewritten elsewhere on | |
185 | * the disk. Flushing these old buffers to reclaim space in the log is | |
186 | * known as checkpointing, and this thread is responsible for that job. | |
187 | */ | |
188 | ||
f7f4bccb | 189 | static int kjournald2(void *arg) |
470decc6 DK |
190 | { |
191 | journal_t *journal = arg; | |
192 | transaction_t *transaction; | |
193 | ||
194 | /* | |
195 | * Set up an interval timer which can be used to trigger a commit wakeup | |
196 | * after the commit interval expires | |
197 | */ | |
198 | setup_timer(&journal->j_commit_timer, commit_timeout, | |
199 | (unsigned long)current); | |
200 | ||
35c80422 NC |
201 | set_freezable(); |
202 | ||
470decc6 DK |
203 | /* Record that the journal thread is running */ |
204 | journal->j_task = current; | |
205 | wake_up(&journal->j_wait_done_commit); | |
206 | ||
470decc6 DK |
207 | /* |
208 | * And now, wait forever for commit wakeup events. | |
209 | */ | |
a931da6a | 210 | write_lock(&journal->j_state_lock); |
470decc6 DK |
211 | |
212 | loop: | |
f7f4bccb | 213 | if (journal->j_flags & JBD2_UNMOUNT) |
470decc6 DK |
214 | goto end_loop; |
215 | ||
216 | jbd_debug(1, "commit_sequence=%d, commit_request=%d\n", | |
217 | journal->j_commit_sequence, journal->j_commit_request); | |
218 | ||
219 | if (journal->j_commit_sequence != journal->j_commit_request) { | |
220 | jbd_debug(1, "OK, requests differ\n"); | |
a931da6a | 221 | write_unlock(&journal->j_state_lock); |
470decc6 | 222 | del_timer_sync(&journal->j_commit_timer); |
f7f4bccb | 223 | jbd2_journal_commit_transaction(journal); |
a931da6a | 224 | write_lock(&journal->j_state_lock); |
470decc6 DK |
225 | goto loop; |
226 | } | |
227 | ||
228 | wake_up(&journal->j_wait_done_commit); | |
229 | if (freezing(current)) { | |
230 | /* | |
231 | * The simpler the better. Flushing journal isn't a | |
232 | * good idea, because that depends on threads that may | |
233 | * be already stopped. | |
234 | */ | |
f7f4bccb | 235 | jbd_debug(1, "Now suspending kjournald2\n"); |
a931da6a | 236 | write_unlock(&journal->j_state_lock); |
a0acae0e | 237 | try_to_freeze(); |
a931da6a | 238 | write_lock(&journal->j_state_lock); |
470decc6 DK |
239 | } else { |
240 | /* | |
241 | * We assume on resume that commits are already there, | |
242 | * so we don't sleep | |
243 | */ | |
244 | DEFINE_WAIT(wait); | |
245 | int should_sleep = 1; | |
246 | ||
247 | prepare_to_wait(&journal->j_wait_commit, &wait, | |
248 | TASK_INTERRUPTIBLE); | |
249 | if (journal->j_commit_sequence != journal->j_commit_request) | |
250 | should_sleep = 0; | |
251 | transaction = journal->j_running_transaction; | |
252 | if (transaction && time_after_eq(jiffies, | |
253 | transaction->t_expires)) | |
254 | should_sleep = 0; | |
f7f4bccb | 255 | if (journal->j_flags & JBD2_UNMOUNT) |
470decc6 DK |
256 | should_sleep = 0; |
257 | if (should_sleep) { | |
a931da6a | 258 | write_unlock(&journal->j_state_lock); |
470decc6 | 259 | schedule(); |
a931da6a | 260 | write_lock(&journal->j_state_lock); |
470decc6 DK |
261 | } |
262 | finish_wait(&journal->j_wait_commit, &wait); | |
263 | } | |
264 | ||
f7f4bccb | 265 | jbd_debug(1, "kjournald2 wakes\n"); |
470decc6 DK |
266 | |
267 | /* | |
268 | * Were we woken up by a commit wakeup event? | |
269 | */ | |
270 | transaction = journal->j_running_transaction; | |
271 | if (transaction && time_after_eq(jiffies, transaction->t_expires)) { | |
272 | journal->j_commit_request = transaction->t_tid; | |
273 | jbd_debug(1, "woke because of timeout\n"); | |
274 | } | |
275 | goto loop; | |
276 | ||
277 | end_loop: | |
a931da6a | 278 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
279 | del_timer_sync(&journal->j_commit_timer); |
280 | journal->j_task = NULL; | |
281 | wake_up(&journal->j_wait_done_commit); | |
282 | jbd_debug(1, "Journal thread exiting.\n"); | |
283 | return 0; | |
284 | } | |
285 | ||
97f06784 | 286 | static int jbd2_journal_start_thread(journal_t *journal) |
470decc6 | 287 | { |
97f06784 PE |
288 | struct task_struct *t; |
289 | ||
90576c0b TT |
290 | t = kthread_run(kjournald2, journal, "jbd2/%s", |
291 | journal->j_devname); | |
97f06784 PE |
292 | if (IS_ERR(t)) |
293 | return PTR_ERR(t); | |
294 | ||
1076d17a | 295 | wait_event(journal->j_wait_done_commit, journal->j_task != NULL); |
97f06784 | 296 | return 0; |
470decc6 DK |
297 | } |
298 | ||
299 | static void journal_kill_thread(journal_t *journal) | |
300 | { | |
a931da6a | 301 | write_lock(&journal->j_state_lock); |
f7f4bccb | 302 | journal->j_flags |= JBD2_UNMOUNT; |
470decc6 DK |
303 | |
304 | while (journal->j_task) { | |
a931da6a | 305 | write_unlock(&journal->j_state_lock); |
3469a32a | 306 | wake_up(&journal->j_wait_commit); |
1076d17a | 307 | wait_event(journal->j_wait_done_commit, journal->j_task == NULL); |
a931da6a | 308 | write_lock(&journal->j_state_lock); |
470decc6 | 309 | } |
a931da6a | 310 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
311 | } |
312 | ||
313 | /* | |
f7f4bccb | 314 | * jbd2_journal_write_metadata_buffer: write a metadata buffer to the journal. |
470decc6 DK |
315 | * |
316 | * Writes a metadata buffer to a given disk block. The actual IO is not | |
317 | * performed but a new buffer_head is constructed which labels the data | |
318 | * to be written with the correct destination disk block. | |
319 | * | |
320 | * Any magic-number escaping which needs to be done will cause a | |
321 | * copy-out here. If the buffer happens to start with the | |
f7f4bccb | 322 | * JBD2_MAGIC_NUMBER, then we can't write it to the log directly: the |
470decc6 DK |
323 | * magic number is only written to the log for descripter blocks. In |
324 | * this case, we copy the data and replace the first word with 0, and we | |
325 | * return a result code which indicates that this buffer needs to be | |
326 | * marked as an escaped buffer in the corresponding log descriptor | |
327 | * block. The missing word can then be restored when the block is read | |
328 | * during recovery. | |
329 | * | |
330 | * If the source buffer has already been modified by a new transaction | |
331 | * since we took the last commit snapshot, we use the frozen copy of | |
f5113eff JK |
332 | * that data for IO. If we end up using the existing buffer_head's data |
333 | * for the write, then we have to make sure nobody modifies it while the | |
334 | * IO is in progress. do_get_write_access() handles this. | |
470decc6 | 335 | * |
f5113eff JK |
336 | * The function returns a pointer to the buffer_head to be used for IO. |
337 | * | |
470decc6 DK |
338 | * |
339 | * Return value: | |
340 | * <0: Error | |
341 | * >=0: Finished OK | |
342 | * | |
343 | * On success: | |
344 | * Bit 0 set == escape performed on the data | |
345 | * Bit 1 set == buffer copy-out performed (kfree the data after IO) | |
346 | */ | |
347 | ||
f7f4bccb | 348 | int jbd2_journal_write_metadata_buffer(transaction_t *transaction, |
470decc6 | 349 | struct journal_head *jh_in, |
f5113eff JK |
350 | struct buffer_head **bh_out, |
351 | sector_t blocknr) | |
470decc6 DK |
352 | { |
353 | int need_copy_out = 0; | |
354 | int done_copy_out = 0; | |
355 | int do_escape = 0; | |
356 | char *mapped_data; | |
357 | struct buffer_head *new_bh; | |
470decc6 DK |
358 | struct page *new_page; |
359 | unsigned int new_offset; | |
360 | struct buffer_head *bh_in = jh2bh(jh_in); | |
96577c43 | 361 | journal_t *journal = transaction->t_journal; |
470decc6 DK |
362 | |
363 | /* | |
364 | * The buffer really shouldn't be locked: only the current committing | |
365 | * transaction is allowed to write it, so nobody else is allowed | |
366 | * to do any IO. | |
367 | * | |
368 | * akpm: except if we're journalling data, and write() output is | |
369 | * also part of a shared mapping, and another thread has | |
370 | * decided to launch a writepage() against this buffer. | |
371 | */ | |
372 | J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in)); | |
373 | ||
6ccaf3e2 | 374 | new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL); |
47def826 | 375 | |
96577c43 | 376 | /* keep subsequent assertions sane */ |
96577c43 | 377 | atomic_set(&new_bh->b_count, 1); |
470decc6 | 378 | |
f5113eff JK |
379 | jbd_lock_bh_state(bh_in); |
380 | repeat: | |
470decc6 DK |
381 | /* |
382 | * If a new transaction has already done a buffer copy-out, then | |
383 | * we use that version of the data for the commit. | |
384 | */ | |
470decc6 DK |
385 | if (jh_in->b_frozen_data) { |
386 | done_copy_out = 1; | |
387 | new_page = virt_to_page(jh_in->b_frozen_data); | |
388 | new_offset = offset_in_page(jh_in->b_frozen_data); | |
389 | } else { | |
390 | new_page = jh2bh(jh_in)->b_page; | |
391 | new_offset = offset_in_page(jh2bh(jh_in)->b_data); | |
392 | } | |
393 | ||
303a8f2a | 394 | mapped_data = kmap_atomic(new_page); |
e06c8227 | 395 | /* |
13ceef09 JK |
396 | * Fire data frozen trigger if data already wasn't frozen. Do this |
397 | * before checking for escaping, as the trigger may modify the magic | |
398 | * offset. If a copy-out happens afterwards, it will have the correct | |
399 | * data in the buffer. | |
e06c8227 | 400 | */ |
13ceef09 JK |
401 | if (!done_copy_out) |
402 | jbd2_buffer_frozen_trigger(jh_in, mapped_data + new_offset, | |
403 | jh_in->b_triggers); | |
e06c8227 | 404 | |
470decc6 DK |
405 | /* |
406 | * Check for escaping | |
407 | */ | |
408 | if (*((__be32 *)(mapped_data + new_offset)) == | |
f7f4bccb | 409 | cpu_to_be32(JBD2_MAGIC_NUMBER)) { |
470decc6 DK |
410 | need_copy_out = 1; |
411 | do_escape = 1; | |
412 | } | |
303a8f2a | 413 | kunmap_atomic(mapped_data); |
470decc6 DK |
414 | |
415 | /* | |
416 | * Do we need to do a data copy? | |
417 | */ | |
418 | if (need_copy_out && !done_copy_out) { | |
419 | char *tmp; | |
420 | ||
421 | jbd_unlock_bh_state(bh_in); | |
af1e76d6 | 422 | tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS); |
e6ec116b | 423 | if (!tmp) { |
f5113eff | 424 | brelse(new_bh); |
e6ec116b TT |
425 | return -ENOMEM; |
426 | } | |
470decc6 DK |
427 | jbd_lock_bh_state(bh_in); |
428 | if (jh_in->b_frozen_data) { | |
af1e76d6 | 429 | jbd2_free(tmp, bh_in->b_size); |
470decc6 DK |
430 | goto repeat; |
431 | } | |
432 | ||
433 | jh_in->b_frozen_data = tmp; | |
303a8f2a | 434 | mapped_data = kmap_atomic(new_page); |
f5113eff | 435 | memcpy(tmp, mapped_data + new_offset, bh_in->b_size); |
303a8f2a | 436 | kunmap_atomic(mapped_data); |
470decc6 DK |
437 | |
438 | new_page = virt_to_page(tmp); | |
439 | new_offset = offset_in_page(tmp); | |
440 | done_copy_out = 1; | |
e06c8227 JB |
441 | |
442 | /* | |
443 | * This isn't strictly necessary, as we're using frozen | |
444 | * data for the escaping, but it keeps consistency with | |
445 | * b_frozen_data usage. | |
446 | */ | |
447 | jh_in->b_frozen_triggers = jh_in->b_triggers; | |
470decc6 DK |
448 | } |
449 | ||
450 | /* | |
451 | * Did we need to do an escaping? Now we've done all the | |
452 | * copying, we can finally do so. | |
453 | */ | |
454 | if (do_escape) { | |
303a8f2a | 455 | mapped_data = kmap_atomic(new_page); |
470decc6 | 456 | *((unsigned int *)(mapped_data + new_offset)) = 0; |
303a8f2a | 457 | kunmap_atomic(mapped_data); |
470decc6 DK |
458 | } |
459 | ||
470decc6 | 460 | set_bh_page(new_bh, new_page, new_offset); |
f5113eff JK |
461 | new_bh->b_size = bh_in->b_size; |
462 | new_bh->b_bdev = journal->j_dev; | |
470decc6 | 463 | new_bh->b_blocknr = blocknr; |
b34090e5 | 464 | new_bh->b_private = bh_in; |
470decc6 DK |
465 | set_buffer_mapped(new_bh); |
466 | set_buffer_dirty(new_bh); | |
467 | ||
f5113eff | 468 | *bh_out = new_bh; |
470decc6 DK |
469 | |
470 | /* | |
471 | * The to-be-written buffer needs to get moved to the io queue, | |
472 | * and the original buffer whose contents we are shadowing or | |
473 | * copying is moved to the transaction's shadow queue. | |
474 | */ | |
475 | JBUFFER_TRACE(jh_in, "file as BJ_Shadow"); | |
96577c43 | 476 | spin_lock(&journal->j_list_lock); |
477 | __jbd2_journal_file_buffer(jh_in, transaction, BJ_Shadow); | |
478 | spin_unlock(&journal->j_list_lock); | |
b34090e5 | 479 | set_buffer_shadow(bh_in); |
96577c43 | 480 | jbd_unlock_bh_state(bh_in); |
481 | ||
470decc6 DK |
482 | return do_escape | (done_copy_out << 1); |
483 | } | |
484 | ||
485 | /* | |
486 | * Allocation code for the journal file. Manage the space left in the | |
487 | * journal, so that we can begin checkpointing when appropriate. | |
488 | */ | |
489 | ||
470decc6 | 490 | /* |
e4471831 TT |
491 | * Called with j_state_lock locked for writing. |
492 | * Returns true if a transaction commit was started. | |
470decc6 | 493 | */ |
f7f4bccb | 494 | int __jbd2_log_start_commit(journal_t *journal, tid_t target) |
470decc6 | 495 | { |
e7b04ac0 ES |
496 | /* Return if the txn has already requested to be committed */ |
497 | if (journal->j_commit_request == target) | |
498 | return 0; | |
499 | ||
470decc6 | 500 | /* |
deeeaf13 TT |
501 | * The only transaction we can possibly wait upon is the |
502 | * currently running transaction (if it exists). Otherwise, | |
503 | * the target tid must be an old one. | |
470decc6 | 504 | */ |
deeeaf13 TT |
505 | if (journal->j_running_transaction && |
506 | journal->j_running_transaction->t_tid == target) { | |
470decc6 | 507 | /* |
bcf3d0bc | 508 | * We want a new commit: OK, mark the request and wakeup the |
470decc6 DK |
509 | * commit thread. We do _not_ do the commit ourselves. |
510 | */ | |
511 | ||
512 | journal->j_commit_request = target; | |
f2a44523 | 513 | jbd_debug(1, "JBD2: requesting commit %d/%d\n", |
470decc6 DK |
514 | journal->j_commit_request, |
515 | journal->j_commit_sequence); | |
9fff24aa | 516 | journal->j_running_transaction->t_requested = jiffies; |
470decc6 DK |
517 | wake_up(&journal->j_wait_commit); |
518 | return 1; | |
deeeaf13 TT |
519 | } else if (!tid_geq(journal->j_commit_request, target)) |
520 | /* This should never happen, but if it does, preserve | |
521 | the evidence before kjournald goes into a loop and | |
522 | increments j_commit_sequence beyond all recognition. */ | |
f2a44523 | 523 | WARN_ONCE(1, "JBD2: bad log_start_commit: %u %u %u %u\n", |
1be2add6 TT |
524 | journal->j_commit_request, |
525 | journal->j_commit_sequence, | |
526 | target, journal->j_running_transaction ? | |
527 | journal->j_running_transaction->t_tid : 0); | |
470decc6 DK |
528 | return 0; |
529 | } | |
530 | ||
f7f4bccb | 531 | int jbd2_log_start_commit(journal_t *journal, tid_t tid) |
470decc6 DK |
532 | { |
533 | int ret; | |
534 | ||
a931da6a | 535 | write_lock(&journal->j_state_lock); |
f7f4bccb | 536 | ret = __jbd2_log_start_commit(journal, tid); |
a931da6a | 537 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
538 | return ret; |
539 | } | |
540 | ||
541 | /* | |
9ff86446 DM |
542 | * Force and wait any uncommitted transactions. We can only force the running |
543 | * transaction if we don't have an active handle, otherwise, we will deadlock. | |
544 | * Returns: <0 in case of error, | |
545 | * 0 if nothing to commit, | |
546 | * 1 if transaction was successfully committed. | |
470decc6 | 547 | */ |
9ff86446 | 548 | static int __jbd2_journal_force_commit(journal_t *journal) |
470decc6 DK |
549 | { |
550 | transaction_t *transaction = NULL; | |
551 | tid_t tid; | |
9ff86446 | 552 | int need_to_start = 0, ret = 0; |
470decc6 | 553 | |
a931da6a | 554 | read_lock(&journal->j_state_lock); |
470decc6 DK |
555 | if (journal->j_running_transaction && !current->journal_info) { |
556 | transaction = journal->j_running_transaction; | |
e4471831 TT |
557 | if (!tid_geq(journal->j_commit_request, transaction->t_tid)) |
558 | need_to_start = 1; | |
470decc6 DK |
559 | } else if (journal->j_committing_transaction) |
560 | transaction = journal->j_committing_transaction; | |
561 | ||
562 | if (!transaction) { | |
9ff86446 | 563 | /* Nothing to commit */ |
a931da6a | 564 | read_unlock(&journal->j_state_lock); |
9ff86446 | 565 | return 0; |
470decc6 | 566 | } |
470decc6 | 567 | tid = transaction->t_tid; |
a931da6a | 568 | read_unlock(&journal->j_state_lock); |
e4471831 TT |
569 | if (need_to_start) |
570 | jbd2_log_start_commit(journal, tid); | |
9ff86446 DM |
571 | ret = jbd2_log_wait_commit(journal, tid); |
572 | if (!ret) | |
573 | ret = 1; | |
574 | ||
575 | return ret; | |
576 | } | |
577 | ||
578 | /** | |
579 | * Force and wait upon a commit if the calling process is not within | |
580 | * transaction. This is used for forcing out undo-protected data which contains | |
581 | * bitmaps, when the fs is running out of space. | |
582 | * | |
583 | * @journal: journal to force | |
584 | * Returns true if progress was made. | |
585 | */ | |
586 | int jbd2_journal_force_commit_nested(journal_t *journal) | |
587 | { | |
588 | int ret; | |
589 | ||
590 | ret = __jbd2_journal_force_commit(journal); | |
591 | return ret > 0; | |
592 | } | |
593 | ||
594 | /** | |
595 | * int journal_force_commit() - force any uncommitted transactions | |
596 | * @journal: journal to force | |
597 | * | |
598 | * Caller want unconditional commit. We can only force the running transaction | |
599 | * if we don't have an active handle, otherwise, we will deadlock. | |
600 | */ | |
601 | int jbd2_journal_force_commit(journal_t *journal) | |
602 | { | |
603 | int ret; | |
604 | ||
605 | J_ASSERT(!current->journal_info); | |
606 | ret = __jbd2_journal_force_commit(journal); | |
607 | if (ret > 0) | |
608 | ret = 0; | |
609 | return ret; | |
470decc6 DK |
610 | } |
611 | ||
612 | /* | |
613 | * Start a commit of the current running transaction (if any). Returns true | |
c88ccea3 JK |
614 | * if a transaction is going to be committed (or is currently already |
615 | * committing), and fills its tid in at *ptid | |
470decc6 | 616 | */ |
f7f4bccb | 617 | int jbd2_journal_start_commit(journal_t *journal, tid_t *ptid) |
470decc6 DK |
618 | { |
619 | int ret = 0; | |
620 | ||
a931da6a | 621 | write_lock(&journal->j_state_lock); |
470decc6 DK |
622 | if (journal->j_running_transaction) { |
623 | tid_t tid = journal->j_running_transaction->t_tid; | |
624 | ||
c88ccea3 JK |
625 | __jbd2_log_start_commit(journal, tid); |
626 | /* There's a running transaction and we've just made sure | |
627 | * it's commit has been scheduled. */ | |
628 | if (ptid) | |
470decc6 | 629 | *ptid = tid; |
c88ccea3 JK |
630 | ret = 1; |
631 | } else if (journal->j_committing_transaction) { | |
470decc6 | 632 | /* |
12810ad7 AB |
633 | * If commit has been started, then we have to wait for |
634 | * completion of that transaction. | |
470decc6 | 635 | */ |
c88ccea3 JK |
636 | if (ptid) |
637 | *ptid = journal->j_committing_transaction->t_tid; | |
470decc6 DK |
638 | ret = 1; |
639 | } | |
a931da6a | 640 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
641 | return ret; |
642 | } | |
643 | ||
bbd2be36 JK |
644 | /* |
645 | * Return 1 if a given transaction has not yet sent barrier request | |
646 | * connected with a transaction commit. If 0 is returned, transaction | |
647 | * may or may not have sent the barrier. Used to avoid sending barrier | |
648 | * twice in common cases. | |
649 | */ | |
650 | int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid) | |
651 | { | |
652 | int ret = 0; | |
653 | transaction_t *commit_trans; | |
654 | ||
655 | if (!(journal->j_flags & JBD2_BARRIER)) | |
656 | return 0; | |
657 | read_lock(&journal->j_state_lock); | |
658 | /* Transaction already committed? */ | |
659 | if (tid_geq(journal->j_commit_sequence, tid)) | |
660 | goto out; | |
661 | commit_trans = journal->j_committing_transaction; | |
662 | if (!commit_trans || commit_trans->t_tid != tid) { | |
663 | ret = 1; | |
664 | goto out; | |
665 | } | |
666 | /* | |
667 | * Transaction is being committed and we already proceeded to | |
668 | * submitting a flush to fs partition? | |
669 | */ | |
670 | if (journal->j_fs_dev != journal->j_dev) { | |
671 | if (!commit_trans->t_need_data_flush || | |
672 | commit_trans->t_state >= T_COMMIT_DFLUSH) | |
673 | goto out; | |
674 | } else { | |
675 | if (commit_trans->t_state >= T_COMMIT_JFLUSH) | |
676 | goto out; | |
677 | } | |
678 | ret = 1; | |
679 | out: | |
680 | read_unlock(&journal->j_state_lock); | |
681 | return ret; | |
682 | } | |
683 | EXPORT_SYMBOL(jbd2_trans_will_send_data_barrier); | |
684 | ||
470decc6 DK |
685 | /* |
686 | * Wait for a specified commit to complete. | |
687 | * The caller may not hold the journal lock. | |
688 | */ | |
f7f4bccb | 689 | int jbd2_log_wait_commit(journal_t *journal, tid_t tid) |
470decc6 DK |
690 | { |
691 | int err = 0; | |
692 | ||
a931da6a | 693 | read_lock(&journal->j_state_lock); |
e23291b9 | 694 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 | 695 | if (!tid_geq(journal->j_commit_request, tid)) { |
75685071 | 696 | printk(KERN_ERR |
470decc6 | 697 | "%s: error: j_commit_request=%d, tid=%d\n", |
329d291f | 698 | __func__, journal->j_commit_request, tid); |
470decc6 | 699 | } |
470decc6 | 700 | #endif |
470decc6 | 701 | while (tid_gt(tid, journal->j_commit_sequence)) { |
f2a44523 | 702 | jbd_debug(1, "JBD2: want %d, j_commit_sequence=%d\n", |
470decc6 | 703 | tid, journal->j_commit_sequence); |
a931da6a | 704 | read_unlock(&journal->j_state_lock); |
3469a32a | 705 | wake_up(&journal->j_wait_commit); |
470decc6 DK |
706 | wait_event(journal->j_wait_done_commit, |
707 | !tid_gt(tid, journal->j_commit_sequence)); | |
a931da6a | 708 | read_lock(&journal->j_state_lock); |
470decc6 | 709 | } |
a931da6a | 710 | read_unlock(&journal->j_state_lock); |
470decc6 | 711 | |
75685071 | 712 | if (unlikely(is_journal_aborted(journal))) |
470decc6 | 713 | err = -EIO; |
470decc6 DK |
714 | return err; |
715 | } | |
716 | ||
d76a3a77 TT |
717 | /* |
718 | * When this function returns the transaction corresponding to tid | |
719 | * will be completed. If the transaction has currently running, start | |
720 | * committing that transaction before waiting for it to complete. If | |
721 | * the transaction id is stale, it is by definition already completed, | |
722 | * so just return SUCCESS. | |
723 | */ | |
724 | int jbd2_complete_transaction(journal_t *journal, tid_t tid) | |
725 | { | |
726 | int need_to_wait = 1; | |
727 | ||
728 | read_lock(&journal->j_state_lock); | |
729 | if (journal->j_running_transaction && | |
730 | journal->j_running_transaction->t_tid == tid) { | |
731 | if (journal->j_commit_request != tid) { | |
732 | /* transaction not yet started, so request it */ | |
733 | read_unlock(&journal->j_state_lock); | |
734 | jbd2_log_start_commit(journal, tid); | |
735 | goto wait_commit; | |
736 | } | |
737 | } else if (!(journal->j_committing_transaction && | |
738 | journal->j_committing_transaction->t_tid == tid)) | |
739 | need_to_wait = 0; | |
740 | read_unlock(&journal->j_state_lock); | |
741 | if (!need_to_wait) | |
742 | return 0; | |
743 | wait_commit: | |
744 | return jbd2_log_wait_commit(journal, tid); | |
745 | } | |
746 | EXPORT_SYMBOL(jbd2_complete_transaction); | |
747 | ||
470decc6 DK |
748 | /* |
749 | * Log buffer allocation routines: | |
750 | */ | |
751 | ||
18eba7aa | 752 | int jbd2_journal_next_log_block(journal_t *journal, unsigned long long *retp) |
470decc6 DK |
753 | { |
754 | unsigned long blocknr; | |
755 | ||
a931da6a | 756 | write_lock(&journal->j_state_lock); |
470decc6 DK |
757 | J_ASSERT(journal->j_free > 1); |
758 | ||
759 | blocknr = journal->j_head; | |
760 | journal->j_head++; | |
761 | journal->j_free--; | |
762 | if (journal->j_head == journal->j_last) | |
763 | journal->j_head = journal->j_first; | |
a931da6a | 764 | write_unlock(&journal->j_state_lock); |
f7f4bccb | 765 | return jbd2_journal_bmap(journal, blocknr, retp); |
470decc6 DK |
766 | } |
767 | ||
768 | /* | |
769 | * Conversion of logical to physical block numbers for the journal | |
770 | * | |
771 | * On external journals the journal blocks are identity-mapped, so | |
772 | * this is a no-op. If needed, we can use j_blk_offset - everything is | |
773 | * ready. | |
774 | */ | |
f7f4bccb | 775 | int jbd2_journal_bmap(journal_t *journal, unsigned long blocknr, |
18eba7aa | 776 | unsigned long long *retp) |
470decc6 DK |
777 | { |
778 | int err = 0; | |
18eba7aa | 779 | unsigned long long ret; |
470decc6 DK |
780 | |
781 | if (journal->j_inode) { | |
782 | ret = bmap(journal->j_inode, blocknr); | |
783 | if (ret) | |
784 | *retp = ret; | |
785 | else { | |
470decc6 DK |
786 | printk(KERN_ALERT "%s: journal block not found " |
787 | "at offset %lu on %s\n", | |
05496769 | 788 | __func__, blocknr, journal->j_devname); |
470decc6 DK |
789 | err = -EIO; |
790 | __journal_abort_soft(journal, err); | |
791 | } | |
792 | } else { | |
793 | *retp = blocknr; /* +journal->j_blk_offset */ | |
794 | } | |
795 | return err; | |
796 | } | |
797 | ||
798 | /* | |
799 | * We play buffer_head aliasing tricks to write data/metadata blocks to | |
800 | * the journal without copying their contents, but for journal | |
801 | * descriptor blocks we do need to generate bona fide buffers. | |
802 | * | |
f7f4bccb | 803 | * After the caller of jbd2_journal_get_descriptor_buffer() has finished modifying |
470decc6 DK |
804 | * the buffer's contents they really should run flush_dcache_page(bh->b_page). |
805 | * But we don't bother doing that, so there will be coherency problems with | |
806 | * mmaps of blockdevs which hold live JBD-controlled filesystems. | |
807 | */ | |
e5a120ae | 808 | struct buffer_head *jbd2_journal_get_descriptor_buffer(journal_t *journal) |
470decc6 DK |
809 | { |
810 | struct buffer_head *bh; | |
18eba7aa | 811 | unsigned long long blocknr; |
470decc6 DK |
812 | int err; |
813 | ||
f7f4bccb | 814 | err = jbd2_journal_next_log_block(journal, &blocknr); |
470decc6 DK |
815 | |
816 | if (err) | |
817 | return NULL; | |
818 | ||
819 | bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize); | |
4b905671 JK |
820 | if (!bh) |
821 | return NULL; | |
470decc6 DK |
822 | lock_buffer(bh); |
823 | memset(bh->b_data, 0, journal->j_blocksize); | |
824 | set_buffer_uptodate(bh); | |
825 | unlock_buffer(bh); | |
826 | BUFFER_TRACE(bh, "return this buffer"); | |
e5a120ae | 827 | return bh; |
470decc6 DK |
828 | } |
829 | ||
79feb521 JK |
830 | /* |
831 | * Return tid of the oldest transaction in the journal and block in the journal | |
832 | * where the transaction starts. | |
833 | * | |
834 | * If the journal is now empty, return which will be the next transaction ID | |
835 | * we will write and where will that transaction start. | |
836 | * | |
837 | * The return value is 0 if journal tail cannot be pushed any further, 1 if | |
838 | * it can. | |
839 | */ | |
840 | int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid, | |
841 | unsigned long *block) | |
842 | { | |
843 | transaction_t *transaction; | |
844 | int ret; | |
845 | ||
846 | read_lock(&journal->j_state_lock); | |
847 | spin_lock(&journal->j_list_lock); | |
848 | transaction = journal->j_checkpoint_transactions; | |
849 | if (transaction) { | |
850 | *tid = transaction->t_tid; | |
851 | *block = transaction->t_log_start; | |
852 | } else if ((transaction = journal->j_committing_transaction) != NULL) { | |
853 | *tid = transaction->t_tid; | |
854 | *block = transaction->t_log_start; | |
855 | } else if ((transaction = journal->j_running_transaction) != NULL) { | |
856 | *tid = transaction->t_tid; | |
857 | *block = journal->j_head; | |
858 | } else { | |
859 | *tid = journal->j_transaction_sequence; | |
860 | *block = journal->j_head; | |
861 | } | |
862 | ret = tid_gt(*tid, journal->j_tail_sequence); | |
863 | spin_unlock(&journal->j_list_lock); | |
864 | read_unlock(&journal->j_state_lock); | |
865 | ||
866 | return ret; | |
867 | } | |
868 | ||
869 | /* | |
870 | * Update information in journal structure and in on disk journal superblock | |
871 | * about log tail. This function does not check whether information passed in | |
872 | * really pushes log tail further. It's responsibility of the caller to make | |
873 | * sure provided log tail information is valid (e.g. by holding | |
874 | * j_checkpoint_mutex all the time between computing log tail and calling this | |
875 | * function as is the case with jbd2_cleanup_journal_tail()). | |
876 | * | |
877 | * Requires j_checkpoint_mutex | |
878 | */ | |
6f6a6fda | 879 | int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block) |
79feb521 JK |
880 | { |
881 | unsigned long freed; | |
6f6a6fda | 882 | int ret; |
79feb521 JK |
883 | |
884 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); | |
885 | ||
886 | /* | |
887 | * We cannot afford for write to remain in drive's caches since as | |
888 | * soon as we update j_tail, next transaction can start reusing journal | |
889 | * space and if we lose sb update during power failure we'd replay | |
890 | * old transaction with possibly newly overwritten data. | |
891 | */ | |
6f6a6fda JQ |
892 | ret = jbd2_journal_update_sb_log_tail(journal, tid, block, WRITE_FUA); |
893 | if (ret) | |
894 | goto out; | |
895 | ||
79feb521 JK |
896 | write_lock(&journal->j_state_lock); |
897 | freed = block - journal->j_tail; | |
898 | if (block < journal->j_tail) | |
899 | freed += journal->j_last - journal->j_first; | |
900 | ||
901 | trace_jbd2_update_log_tail(journal, tid, block, freed); | |
902 | jbd_debug(1, | |
903 | "Cleaning journal tail from %d to %d (offset %lu), " | |
904 | "freeing %lu\n", | |
905 | journal->j_tail_sequence, tid, block, freed); | |
906 | ||
907 | journal->j_free += freed; | |
908 | journal->j_tail_sequence = tid; | |
909 | journal->j_tail = block; | |
910 | write_unlock(&journal->j_state_lock); | |
6f6a6fda JQ |
911 | |
912 | out: | |
913 | return ret; | |
79feb521 JK |
914 | } |
915 | ||
3339578f JK |
916 | /* |
917 | * This is a variaon of __jbd2_update_log_tail which checks for validity of | |
918 | * provided log tail and locks j_checkpoint_mutex. So it is safe against races | |
919 | * with other threads updating log tail. | |
920 | */ | |
921 | void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block) | |
922 | { | |
923 | mutex_lock(&journal->j_checkpoint_mutex); | |
924 | if (tid_gt(tid, journal->j_tail_sequence)) | |
925 | __jbd2_update_log_tail(journal, tid, block); | |
926 | mutex_unlock(&journal->j_checkpoint_mutex); | |
927 | } | |
928 | ||
8e85fb3f JL |
929 | struct jbd2_stats_proc_session { |
930 | journal_t *journal; | |
931 | struct transaction_stats_s *stats; | |
932 | int start; | |
933 | int max; | |
934 | }; | |
935 | ||
8e85fb3f JL |
936 | static void *jbd2_seq_info_start(struct seq_file *seq, loff_t *pos) |
937 | { | |
938 | return *pos ? NULL : SEQ_START_TOKEN; | |
939 | } | |
940 | ||
941 | static void *jbd2_seq_info_next(struct seq_file *seq, void *v, loff_t *pos) | |
942 | { | |
943 | return NULL; | |
944 | } | |
945 | ||
946 | static int jbd2_seq_info_show(struct seq_file *seq, void *v) | |
947 | { | |
948 | struct jbd2_stats_proc_session *s = seq->private; | |
949 | ||
950 | if (v != SEQ_START_TOKEN) | |
951 | return 0; | |
9fff24aa TT |
952 | seq_printf(seq, "%lu transactions (%lu requested), " |
953 | "each up to %u blocks\n", | |
954 | s->stats->ts_tid, s->stats->ts_requested, | |
955 | s->journal->j_max_transaction_buffers); | |
8e85fb3f JL |
956 | if (s->stats->ts_tid == 0) |
957 | return 0; | |
958 | seq_printf(seq, "average: \n %ums waiting for transaction\n", | |
bf699327 | 959 | jiffies_to_msecs(s->stats->run.rs_wait / s->stats->ts_tid)); |
9fff24aa TT |
960 | seq_printf(seq, " %ums request delay\n", |
961 | (s->stats->ts_requested == 0) ? 0 : | |
962 | jiffies_to_msecs(s->stats->run.rs_request_delay / | |
963 | s->stats->ts_requested)); | |
8e85fb3f | 964 | seq_printf(seq, " %ums running transaction\n", |
bf699327 | 965 | jiffies_to_msecs(s->stats->run.rs_running / s->stats->ts_tid)); |
8e85fb3f | 966 | seq_printf(seq, " %ums transaction was being locked\n", |
bf699327 | 967 | jiffies_to_msecs(s->stats->run.rs_locked / s->stats->ts_tid)); |
8e85fb3f | 968 | seq_printf(seq, " %ums flushing data (in ordered mode)\n", |
bf699327 | 969 | jiffies_to_msecs(s->stats->run.rs_flushing / s->stats->ts_tid)); |
8e85fb3f | 970 | seq_printf(seq, " %ums logging transaction\n", |
bf699327 | 971 | jiffies_to_msecs(s->stats->run.rs_logging / s->stats->ts_tid)); |
c225aa57 SHT |
972 | seq_printf(seq, " %lluus average transaction commit time\n", |
973 | div_u64(s->journal->j_average_commit_time, 1000)); | |
8e85fb3f | 974 | seq_printf(seq, " %lu handles per transaction\n", |
bf699327 | 975 | s->stats->run.rs_handle_count / s->stats->ts_tid); |
8e85fb3f | 976 | seq_printf(seq, " %lu blocks per transaction\n", |
bf699327 | 977 | s->stats->run.rs_blocks / s->stats->ts_tid); |
8e85fb3f | 978 | seq_printf(seq, " %lu logged blocks per transaction\n", |
bf699327 | 979 | s->stats->run.rs_blocks_logged / s->stats->ts_tid); |
8e85fb3f JL |
980 | return 0; |
981 | } | |
982 | ||
983 | static void jbd2_seq_info_stop(struct seq_file *seq, void *v) | |
984 | { | |
985 | } | |
986 | ||
88e9d34c | 987 | static const struct seq_operations jbd2_seq_info_ops = { |
8e85fb3f JL |
988 | .start = jbd2_seq_info_start, |
989 | .next = jbd2_seq_info_next, | |
990 | .stop = jbd2_seq_info_stop, | |
991 | .show = jbd2_seq_info_show, | |
992 | }; | |
993 | ||
994 | static int jbd2_seq_info_open(struct inode *inode, struct file *file) | |
995 | { | |
d9dda78b | 996 | journal_t *journal = PDE_DATA(inode); |
8e85fb3f JL |
997 | struct jbd2_stats_proc_session *s; |
998 | int rc, size; | |
999 | ||
1000 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
1001 | if (s == NULL) | |
1002 | return -ENOMEM; | |
1003 | size = sizeof(struct transaction_stats_s); | |
1004 | s->stats = kmalloc(size, GFP_KERNEL); | |
1005 | if (s->stats == NULL) { | |
1006 | kfree(s); | |
1007 | return -ENOMEM; | |
1008 | } | |
1009 | spin_lock(&journal->j_history_lock); | |
1010 | memcpy(s->stats, &journal->j_stats, size); | |
1011 | s->journal = journal; | |
1012 | spin_unlock(&journal->j_history_lock); | |
1013 | ||
1014 | rc = seq_open(file, &jbd2_seq_info_ops); | |
1015 | if (rc == 0) { | |
1016 | struct seq_file *m = file->private_data; | |
1017 | m->private = s; | |
1018 | } else { | |
1019 | kfree(s->stats); | |
1020 | kfree(s); | |
1021 | } | |
1022 | return rc; | |
1023 | ||
1024 | } | |
1025 | ||
1026 | static int jbd2_seq_info_release(struct inode *inode, struct file *file) | |
1027 | { | |
1028 | struct seq_file *seq = file->private_data; | |
1029 | struct jbd2_stats_proc_session *s = seq->private; | |
1030 | kfree(s->stats); | |
1031 | kfree(s); | |
1032 | return seq_release(inode, file); | |
1033 | } | |
1034 | ||
828c0950 | 1035 | static const struct file_operations jbd2_seq_info_fops = { |
8e85fb3f JL |
1036 | .owner = THIS_MODULE, |
1037 | .open = jbd2_seq_info_open, | |
1038 | .read = seq_read, | |
1039 | .llseek = seq_lseek, | |
1040 | .release = jbd2_seq_info_release, | |
1041 | }; | |
1042 | ||
1043 | static struct proc_dir_entry *proc_jbd2_stats; | |
1044 | ||
1045 | static void jbd2_stats_proc_init(journal_t *journal) | |
1046 | { | |
05496769 | 1047 | journal->j_proc_entry = proc_mkdir(journal->j_devname, proc_jbd2_stats); |
8e85fb3f | 1048 | if (journal->j_proc_entry) { |
79da3664 DL |
1049 | proc_create_data("info", S_IRUGO, journal->j_proc_entry, |
1050 | &jbd2_seq_info_fops, journal); | |
8e85fb3f JL |
1051 | } |
1052 | } | |
1053 | ||
1054 | static void jbd2_stats_proc_exit(journal_t *journal) | |
1055 | { | |
8e85fb3f | 1056 | remove_proc_entry("info", journal->j_proc_entry); |
05496769 | 1057 | remove_proc_entry(journal->j_devname, proc_jbd2_stats); |
8e85fb3f JL |
1058 | } |
1059 | ||
470decc6 DK |
1060 | /* |
1061 | * Management for journal control blocks: functions to create and | |
1062 | * destroy journal_t structures, and to initialise and read existing | |
1063 | * journal blocks from disk. */ | |
1064 | ||
1065 | /* First: create and setup a journal_t object in memory. We initialise | |
1066 | * very few fields yet: that has to wait until we have created the | |
1067 | * journal structures from from scratch, or loaded them from disk. */ | |
1068 | ||
1069 | static journal_t * journal_init_common (void) | |
1070 | { | |
1071 | journal_t *journal; | |
1072 | int err; | |
1073 | ||
3ebfdf88 | 1074 | journal = kzalloc(sizeof(*journal), GFP_KERNEL); |
470decc6 | 1075 | if (!journal) |
b7271b0a | 1076 | return NULL; |
470decc6 DK |
1077 | |
1078 | init_waitqueue_head(&journal->j_wait_transaction_locked); | |
470decc6 | 1079 | init_waitqueue_head(&journal->j_wait_done_commit); |
470decc6 DK |
1080 | init_waitqueue_head(&journal->j_wait_commit); |
1081 | init_waitqueue_head(&journal->j_wait_updates); | |
8f7d89f3 | 1082 | init_waitqueue_head(&journal->j_wait_reserved); |
470decc6 DK |
1083 | mutex_init(&journal->j_barrier); |
1084 | mutex_init(&journal->j_checkpoint_mutex); | |
1085 | spin_lock_init(&journal->j_revoke_lock); | |
1086 | spin_lock_init(&journal->j_list_lock); | |
a931da6a | 1087 | rwlock_init(&journal->j_state_lock); |
470decc6 | 1088 | |
cd02ff0b | 1089 | journal->j_commit_interval = (HZ * JBD2_DEFAULT_MAX_COMMIT_AGE); |
30773840 TT |
1090 | journal->j_min_batch_time = 0; |
1091 | journal->j_max_batch_time = 15000; /* 15ms */ | |
8f7d89f3 | 1092 | atomic_set(&journal->j_reserved_credits, 0); |
470decc6 DK |
1093 | |
1094 | /* The journal is marked for error until we succeed with recovery! */ | |
f7f4bccb | 1095 | journal->j_flags = JBD2_ABORT; |
470decc6 DK |
1096 | |
1097 | /* Set up a default-sized revoke table for the new mount. */ | |
f7f4bccb | 1098 | err = jbd2_journal_init_revoke(journal, JOURNAL_REVOKE_DEFAULT_HASH); |
470decc6 DK |
1099 | if (err) { |
1100 | kfree(journal); | |
b7271b0a | 1101 | return NULL; |
470decc6 | 1102 | } |
8e85fb3f | 1103 | |
bf699327 | 1104 | spin_lock_init(&journal->j_history_lock); |
8e85fb3f | 1105 | |
470decc6 | 1106 | return journal; |
470decc6 DK |
1107 | } |
1108 | ||
f7f4bccb | 1109 | /* jbd2_journal_init_dev and jbd2_journal_init_inode: |
470decc6 DK |
1110 | * |
1111 | * Create a journal structure assigned some fixed set of disk blocks to | |
1112 | * the journal. We don't actually touch those disk blocks yet, but we | |
1113 | * need to set up all of the mapping information to tell the journaling | |
1114 | * system where the journal blocks are. | |
1115 | * | |
1116 | */ | |
1117 | ||
1118 | /** | |
5648ba5b | 1119 | * journal_t * jbd2_journal_init_dev() - creates and initialises a journal structure |
470decc6 DK |
1120 | * @bdev: Block device on which to create the journal |
1121 | * @fs_dev: Device which hold journalled filesystem for this journal. | |
1122 | * @start: Block nr Start of journal. | |
1123 | * @len: Length of the journal in blocks. | |
1124 | * @blocksize: blocksize of journalling device | |
5648ba5b RD |
1125 | * |
1126 | * Returns: a newly created journal_t * | |
470decc6 | 1127 | * |
f7f4bccb | 1128 | * jbd2_journal_init_dev creates a journal which maps a fixed contiguous |
470decc6 DK |
1129 | * range of blocks on an arbitrary block device. |
1130 | * | |
1131 | */ | |
f7f4bccb | 1132 | journal_t * jbd2_journal_init_dev(struct block_device *bdev, |
470decc6 | 1133 | struct block_device *fs_dev, |
18eba7aa | 1134 | unsigned long long start, int len, int blocksize) |
470decc6 DK |
1135 | { |
1136 | journal_t *journal = journal_init_common(); | |
1137 | struct buffer_head *bh; | |
1138 | int n; | |
1139 | ||
1140 | if (!journal) | |
1141 | return NULL; | |
1142 | ||
1143 | /* journal descriptor can store up to n blocks -bzzz */ | |
1144 | journal->j_blocksize = blocksize; | |
0587aa3d | 1145 | journal->j_dev = bdev; |
1146 | journal->j_fs_dev = fs_dev; | |
1147 | journal->j_blk_offset = start; | |
1148 | journal->j_maxlen = len; | |
1149 | bdevname(journal->j_dev, journal->j_devname); | |
81ae394b | 1150 | strreplace(journal->j_devname, '/', '!'); |
4b905671 | 1151 | jbd2_stats_proc_init(journal); |
470decc6 DK |
1152 | n = journal->j_blocksize / sizeof(journal_block_tag_t); |
1153 | journal->j_wbufsize = n; | |
1154 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
1155 | if (!journal->j_wbuf) { | |
25985edc | 1156 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
329d291f | 1157 | __func__); |
4b905671 | 1158 | goto out_err; |
470decc6 | 1159 | } |
470decc6 DK |
1160 | |
1161 | bh = __getblk(journal->j_dev, start, journal->j_blocksize); | |
4b905671 JK |
1162 | if (!bh) { |
1163 | printk(KERN_ERR | |
1164 | "%s: Cannot get buffer for journal superblock\n", | |
1165 | __func__); | |
1166 | goto out_err; | |
1167 | } | |
470decc6 DK |
1168 | journal->j_sb_buffer = bh; |
1169 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
4b905671 | 1170 | |
470decc6 | 1171 | return journal; |
4b905671 | 1172 | out_err: |
7b02bec0 | 1173 | kfree(journal->j_wbuf); |
4b905671 JK |
1174 | jbd2_stats_proc_exit(journal); |
1175 | kfree(journal); | |
1176 | return NULL; | |
470decc6 DK |
1177 | } |
1178 | ||
1179 | /** | |
f7f4bccb | 1180 | * journal_t * jbd2_journal_init_inode () - creates a journal which maps to a inode. |
470decc6 DK |
1181 | * @inode: An inode to create the journal in |
1182 | * | |
f7f4bccb | 1183 | * jbd2_journal_init_inode creates a journal which maps an on-disk inode as |
470decc6 DK |
1184 | * the journal. The inode must exist already, must support bmap() and |
1185 | * must have all data blocks preallocated. | |
1186 | */ | |
f7f4bccb | 1187 | journal_t * jbd2_journal_init_inode (struct inode *inode) |
470decc6 DK |
1188 | { |
1189 | struct buffer_head *bh; | |
1190 | journal_t *journal = journal_init_common(); | |
05496769 | 1191 | char *p; |
470decc6 DK |
1192 | int err; |
1193 | int n; | |
18eba7aa | 1194 | unsigned long long blocknr; |
470decc6 DK |
1195 | |
1196 | if (!journal) | |
1197 | return NULL; | |
1198 | ||
1199 | journal->j_dev = journal->j_fs_dev = inode->i_sb->s_bdev; | |
1200 | journal->j_inode = inode; | |
05496769 | 1201 | bdevname(journal->j_dev, journal->j_devname); |
81ae394b | 1202 | p = strreplace(journal->j_devname, '/', '!'); |
90576c0b | 1203 | sprintf(p, "-%lu", journal->j_inode->i_ino); |
470decc6 DK |
1204 | jbd_debug(1, |
1205 | "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n", | |
1206 | journal, inode->i_sb->s_id, inode->i_ino, | |
1207 | (long long) inode->i_size, | |
1208 | inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize); | |
1209 | ||
1210 | journal->j_maxlen = inode->i_size >> inode->i_sb->s_blocksize_bits; | |
1211 | journal->j_blocksize = inode->i_sb->s_blocksize; | |
8e85fb3f | 1212 | jbd2_stats_proc_init(journal); |
470decc6 DK |
1213 | |
1214 | /* journal descriptor can store up to n blocks -bzzz */ | |
1215 | n = journal->j_blocksize / sizeof(journal_block_tag_t); | |
1216 | journal->j_wbufsize = n; | |
1217 | journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); | |
1218 | if (!journal->j_wbuf) { | |
25985edc | 1219 | printk(KERN_ERR "%s: Can't allocate bhs for commit thread\n", |
329d291f | 1220 | __func__); |
4b905671 | 1221 | goto out_err; |
470decc6 DK |
1222 | } |
1223 | ||
f7f4bccb | 1224 | err = jbd2_journal_bmap(journal, 0, &blocknr); |
470decc6 DK |
1225 | /* If that failed, give up */ |
1226 | if (err) { | |
3c26bdb4 | 1227 | printk(KERN_ERR "%s: Cannot locate journal superblock\n", |
329d291f | 1228 | __func__); |
4b905671 | 1229 | goto out_err; |
470decc6 DK |
1230 | } |
1231 | ||
a49058fa | 1232 | bh = getblk_unmovable(journal->j_dev, blocknr, journal->j_blocksize); |
4b905671 JK |
1233 | if (!bh) { |
1234 | printk(KERN_ERR | |
1235 | "%s: Cannot get buffer for journal superblock\n", | |
1236 | __func__); | |
1237 | goto out_err; | |
1238 | } | |
470decc6 DK |
1239 | journal->j_sb_buffer = bh; |
1240 | journal->j_superblock = (journal_superblock_t *)bh->b_data; | |
1241 | ||
1242 | return journal; | |
4b905671 | 1243 | out_err: |
7b02bec0 | 1244 | kfree(journal->j_wbuf); |
4b905671 JK |
1245 | jbd2_stats_proc_exit(journal); |
1246 | kfree(journal); | |
1247 | return NULL; | |
470decc6 DK |
1248 | } |
1249 | ||
1250 | /* | |
1251 | * If the journal init or create aborts, we need to mark the journal | |
1252 | * superblock as being NULL to prevent the journal destroy from writing | |
1253 | * back a bogus superblock. | |
1254 | */ | |
1255 | static void journal_fail_superblock (journal_t *journal) | |
1256 | { | |
1257 | struct buffer_head *bh = journal->j_sb_buffer; | |
1258 | brelse(bh); | |
1259 | journal->j_sb_buffer = NULL; | |
1260 | } | |
1261 | ||
1262 | /* | |
1263 | * Given a journal_t structure, initialise the various fields for | |
1264 | * startup of a new journaling session. We use this both when creating | |
1265 | * a journal, and after recovering an old journal to reset it for | |
1266 | * subsequent use. | |
1267 | */ | |
1268 | ||
1269 | static int journal_reset(journal_t *journal) | |
1270 | { | |
1271 | journal_superblock_t *sb = journal->j_superblock; | |
18eba7aa | 1272 | unsigned long long first, last; |
470decc6 DK |
1273 | |
1274 | first = be32_to_cpu(sb->s_first); | |
1275 | last = be32_to_cpu(sb->s_maxlen); | |
f6f50e28 | 1276 | if (first + JBD2_MIN_JOURNAL_BLOCKS > last + 1) { |
f2a44523 | 1277 | printk(KERN_ERR "JBD2: Journal too short (blocks %llu-%llu).\n", |
f6f50e28 JK |
1278 | first, last); |
1279 | journal_fail_superblock(journal); | |
1280 | return -EINVAL; | |
1281 | } | |
470decc6 DK |
1282 | |
1283 | journal->j_first = first; | |
1284 | journal->j_last = last; | |
1285 | ||
1286 | journal->j_head = first; | |
1287 | journal->j_tail = first; | |
1288 | journal->j_free = last - first; | |
1289 | ||
1290 | journal->j_tail_sequence = journal->j_transaction_sequence; | |
1291 | journal->j_commit_sequence = journal->j_transaction_sequence - 1; | |
1292 | journal->j_commit_request = journal->j_commit_sequence; | |
1293 | ||
1294 | journal->j_max_transaction_buffers = journal->j_maxlen / 4; | |
1295 | ||
470decc6 DK |
1296 | /* |
1297 | * As a special case, if the on-disk copy is already marked as needing | |
24bcc89c JK |
1298 | * no recovery (s_start == 0), then we can safely defer the superblock |
1299 | * update until the next commit by setting JBD2_FLUSHED. This avoids | |
470decc6 DK |
1300 | * attempting a write to a potential-readonly device. |
1301 | */ | |
24bcc89c | 1302 | if (sb->s_start == 0) { |
f2a44523 | 1303 | jbd_debug(1, "JBD2: Skipping superblock update on recovered sb " |
470decc6 DK |
1304 | "(start %ld, seq %d, errno %d)\n", |
1305 | journal->j_tail, journal->j_tail_sequence, | |
1306 | journal->j_errno); | |
24bcc89c JK |
1307 | journal->j_flags |= JBD2_FLUSHED; |
1308 | } else { | |
a78bb11d JK |
1309 | /* Lock here to make assertions happy... */ |
1310 | mutex_lock(&journal->j_checkpoint_mutex); | |
79feb521 JK |
1311 | /* |
1312 | * Update log tail information. We use WRITE_FUA since new | |
1313 | * transaction will start reusing journal space and so we | |
1314 | * must make sure information about current log tail is on | |
1315 | * disk before that. | |
1316 | */ | |
1317 | jbd2_journal_update_sb_log_tail(journal, | |
1318 | journal->j_tail_sequence, | |
1319 | journal->j_tail, | |
1320 | WRITE_FUA); | |
a78bb11d | 1321 | mutex_unlock(&journal->j_checkpoint_mutex); |
470decc6 | 1322 | } |
24bcc89c JK |
1323 | return jbd2_journal_start_thread(journal); |
1324 | } | |
470decc6 | 1325 | |
6f6a6fda | 1326 | static int jbd2_write_superblock(journal_t *journal, int write_op) |
24bcc89c JK |
1327 | { |
1328 | struct buffer_head *bh = journal->j_sb_buffer; | |
fe52d17c | 1329 | journal_superblock_t *sb = journal->j_superblock; |
79feb521 | 1330 | int ret; |
470decc6 | 1331 | |
79feb521 JK |
1332 | trace_jbd2_write_superblock(journal, write_op); |
1333 | if (!(journal->j_flags & JBD2_BARRIER)) | |
1334 | write_op &= ~(REQ_FUA | REQ_FLUSH); | |
1335 | lock_buffer(bh); | |
914258bf TT |
1336 | if (buffer_write_io_error(bh)) { |
1337 | /* | |
1338 | * Oh, dear. A previous attempt to write the journal | |
1339 | * superblock failed. This could happen because the | |
1340 | * USB device was yanked out. Or it could happen to | |
1341 | * be a transient write error and maybe the block will | |
1342 | * be remapped. Nothing we can do but to retry the | |
1343 | * write and hope for the best. | |
1344 | */ | |
1345 | printk(KERN_ERR "JBD2: previous I/O error detected " | |
1346 | "for journal superblock update for %s.\n", | |
1347 | journal->j_devname); | |
1348 | clear_buffer_write_io_error(bh); | |
1349 | set_buffer_uptodate(bh); | |
1350 | } | |
fe52d17c | 1351 | jbd2_superblock_csum_set(journal, sb); |
79feb521 JK |
1352 | get_bh(bh); |
1353 | bh->b_end_io = end_buffer_write_sync; | |
1354 | ret = submit_bh(write_op, bh); | |
1355 | wait_on_buffer(bh); | |
24bcc89c | 1356 | if (buffer_write_io_error(bh)) { |
24bcc89c JK |
1357 | clear_buffer_write_io_error(bh); |
1358 | set_buffer_uptodate(bh); | |
79feb521 JK |
1359 | ret = -EIO; |
1360 | } | |
1361 | if (ret) { | |
1362 | printk(KERN_ERR "JBD2: Error %d detected when updating " | |
1363 | "journal superblock for %s.\n", ret, | |
1364 | journal->j_devname); | |
6f6a6fda | 1365 | jbd2_journal_abort(journal, ret); |
24bcc89c | 1366 | } |
6f6a6fda JQ |
1367 | |
1368 | return ret; | |
24bcc89c JK |
1369 | } |
1370 | ||
1371 | /** | |
1372 | * jbd2_journal_update_sb_log_tail() - Update log tail in journal sb on disk. | |
1373 | * @journal: The journal to update. | |
79feb521 JK |
1374 | * @tail_tid: TID of the new transaction at the tail of the log |
1375 | * @tail_block: The first block of the transaction at the tail of the log | |
1376 | * @write_op: With which operation should we write the journal sb | |
24bcc89c JK |
1377 | * |
1378 | * Update a journal's superblock information about log tail and write it to | |
1379 | * disk, waiting for the IO to complete. | |
1380 | */ | |
6f6a6fda | 1381 | int jbd2_journal_update_sb_log_tail(journal_t *journal, tid_t tail_tid, |
79feb521 | 1382 | unsigned long tail_block, int write_op) |
24bcc89c JK |
1383 | { |
1384 | journal_superblock_t *sb = journal->j_superblock; | |
6f6a6fda | 1385 | int ret; |
24bcc89c | 1386 | |
a78bb11d | 1387 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); |
79feb521 JK |
1388 | jbd_debug(1, "JBD2: updating superblock (start %lu, seq %u)\n", |
1389 | tail_block, tail_tid); | |
470decc6 | 1390 | |
79feb521 JK |
1391 | sb->s_sequence = cpu_to_be32(tail_tid); |
1392 | sb->s_start = cpu_to_be32(tail_block); | |
470decc6 | 1393 | |
6f6a6fda JQ |
1394 | ret = jbd2_write_superblock(journal, write_op); |
1395 | if (ret) | |
1396 | goto out; | |
470decc6 | 1397 | |
24bcc89c JK |
1398 | /* Log is no longer empty */ |
1399 | write_lock(&journal->j_state_lock); | |
1400 | WARN_ON(!sb->s_sequence); | |
1401 | journal->j_flags &= ~JBD2_FLUSHED; | |
1402 | write_unlock(&journal->j_state_lock); | |
6f6a6fda JQ |
1403 | |
1404 | out: | |
1405 | return ret; | |
24bcc89c | 1406 | } |
2201c590 | 1407 | |
24bcc89c JK |
1408 | /** |
1409 | * jbd2_mark_journal_empty() - Mark on disk journal as empty. | |
1410 | * @journal: The journal to update. | |
1411 | * | |
1412 | * Update a journal's dynamic superblock fields to show that journal is empty. | |
1413 | * Write updated superblock to disk waiting for IO to complete. | |
1414 | */ | |
1415 | static void jbd2_mark_journal_empty(journal_t *journal) | |
1416 | { | |
1417 | journal_superblock_t *sb = journal->j_superblock; | |
914258bf | 1418 | |
a78bb11d | 1419 | BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); |
a931da6a | 1420 | read_lock(&journal->j_state_lock); |
eeecef0a ES |
1421 | /* Is it already empty? */ |
1422 | if (sb->s_start == 0) { | |
1423 | read_unlock(&journal->j_state_lock); | |
1424 | return; | |
1425 | } | |
24bcc89c JK |
1426 | jbd_debug(1, "JBD2: Marking journal as empty (seq %d)\n", |
1427 | journal->j_tail_sequence); | |
470decc6 DK |
1428 | |
1429 | sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); | |
24bcc89c | 1430 | sb->s_start = cpu_to_be32(0); |
a931da6a | 1431 | read_unlock(&journal->j_state_lock); |
470decc6 | 1432 | |
79feb521 | 1433 | jbd2_write_superblock(journal, WRITE_FUA); |
470decc6 | 1434 | |
24bcc89c | 1435 | /* Log is no longer empty */ |
a931da6a | 1436 | write_lock(&journal->j_state_lock); |
24bcc89c | 1437 | journal->j_flags |= JBD2_FLUSHED; |
a931da6a | 1438 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1439 | } |
1440 | ||
24bcc89c JK |
1441 | |
1442 | /** | |
1443 | * jbd2_journal_update_sb_errno() - Update error in the journal. | |
1444 | * @journal: The journal to update. | |
1445 | * | |
1446 | * Update a journal's errno. Write updated superblock to disk waiting for IO | |
1447 | * to complete. | |
1448 | */ | |
d796c52e | 1449 | void jbd2_journal_update_sb_errno(journal_t *journal) |
24bcc89c JK |
1450 | { |
1451 | journal_superblock_t *sb = journal->j_superblock; | |
1452 | ||
1453 | read_lock(&journal->j_state_lock); | |
1454 | jbd_debug(1, "JBD2: updating superblock error (errno %d)\n", | |
1455 | journal->j_errno); | |
1456 | sb->s_errno = cpu_to_be32(journal->j_errno); | |
1457 | read_unlock(&journal->j_state_lock); | |
1458 | ||
564bc402 | 1459 | jbd2_write_superblock(journal, WRITE_FUA); |
24bcc89c | 1460 | } |
d796c52e | 1461 | EXPORT_SYMBOL(jbd2_journal_update_sb_errno); |
24bcc89c | 1462 | |
470decc6 DK |
1463 | /* |
1464 | * Read the superblock for a given journal, performing initial | |
1465 | * validation of the format. | |
1466 | */ | |
470decc6 DK |
1467 | static int journal_get_superblock(journal_t *journal) |
1468 | { | |
1469 | struct buffer_head *bh; | |
1470 | journal_superblock_t *sb; | |
1471 | int err = -EIO; | |
1472 | ||
1473 | bh = journal->j_sb_buffer; | |
1474 | ||
1475 | J_ASSERT(bh != NULL); | |
1476 | if (!buffer_uptodate(bh)) { | |
1477 | ll_rw_block(READ, 1, &bh); | |
1478 | wait_on_buffer(bh); | |
1479 | if (!buffer_uptodate(bh)) { | |
f2a44523 EG |
1480 | printk(KERN_ERR |
1481 | "JBD2: IO error reading journal superblock\n"); | |
470decc6 DK |
1482 | goto out; |
1483 | } | |
1484 | } | |
1485 | ||
25ed6e8a DW |
1486 | if (buffer_verified(bh)) |
1487 | return 0; | |
1488 | ||
470decc6 DK |
1489 | sb = journal->j_superblock; |
1490 | ||
1491 | err = -EINVAL; | |
1492 | ||
f7f4bccb | 1493 | if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) || |
470decc6 | 1494 | sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) { |
f2a44523 | 1495 | printk(KERN_WARNING "JBD2: no valid journal superblock found\n"); |
470decc6 DK |
1496 | goto out; |
1497 | } | |
1498 | ||
1499 | switch(be32_to_cpu(sb->s_header.h_blocktype)) { | |
f7f4bccb | 1500 | case JBD2_SUPERBLOCK_V1: |
470decc6 DK |
1501 | journal->j_format_version = 1; |
1502 | break; | |
f7f4bccb | 1503 | case JBD2_SUPERBLOCK_V2: |
470decc6 DK |
1504 | journal->j_format_version = 2; |
1505 | break; | |
1506 | default: | |
f2a44523 | 1507 | printk(KERN_WARNING "JBD2: unrecognised superblock format ID\n"); |
470decc6 DK |
1508 | goto out; |
1509 | } | |
1510 | ||
1511 | if (be32_to_cpu(sb->s_maxlen) < journal->j_maxlen) | |
1512 | journal->j_maxlen = be32_to_cpu(sb->s_maxlen); | |
1513 | else if (be32_to_cpu(sb->s_maxlen) > journal->j_maxlen) { | |
f2a44523 | 1514 | printk(KERN_WARNING "JBD2: journal file too short\n"); |
470decc6 DK |
1515 | goto out; |
1516 | } | |
1517 | ||
8762202d EG |
1518 | if (be32_to_cpu(sb->s_first) == 0 || |
1519 | be32_to_cpu(sb->s_first) >= journal->j_maxlen) { | |
1520 | printk(KERN_WARNING | |
1521 | "JBD2: Invalid start block of journal: %u\n", | |
1522 | be32_to_cpu(sb->s_first)); | |
1523 | goto out; | |
1524 | } | |
1525 | ||
56316a0d DW |
1526 | if (jbd2_has_feature_csum2(journal) && |
1527 | jbd2_has_feature_csum3(journal)) { | |
db9ee220 DW |
1528 | /* Can't have checksum v2 and v3 at the same time! */ |
1529 | printk(KERN_ERR "JBD2: Can't enable checksumming v2 and v3 " | |
1530 | "at the same time!\n"); | |
1531 | goto out; | |
1532 | } | |
1533 | ||
8595798c | 1534 | if (jbd2_journal_has_csum_v2or3_feature(journal) && |
56316a0d | 1535 | jbd2_has_feature_checksum(journal)) { |
feb8c6d3 DW |
1536 | /* Can't have checksum v1 and v2 on at the same time! */ |
1537 | printk(KERN_ERR "JBD2: Can't enable checksumming v1 and v2/3 " | |
1538 | "at the same time!\n"); | |
1539 | goto out; | |
1540 | } | |
1541 | ||
25ed6e8a | 1542 | if (!jbd2_verify_csum_type(journal, sb)) { |
a67c848a | 1543 | printk(KERN_ERR "JBD2: Unknown checksum type\n"); |
25ed6e8a DW |
1544 | goto out; |
1545 | } | |
1546 | ||
01b5adce | 1547 | /* Load the checksum driver */ |
8595798c | 1548 | if (jbd2_journal_has_csum_v2or3_feature(journal)) { |
01b5adce DW |
1549 | journal->j_chksum_driver = crypto_alloc_shash("crc32c", 0, 0); |
1550 | if (IS_ERR(journal->j_chksum_driver)) { | |
a67c848a | 1551 | printk(KERN_ERR "JBD2: Cannot load crc32c driver.\n"); |
01b5adce DW |
1552 | err = PTR_ERR(journal->j_chksum_driver); |
1553 | journal->j_chksum_driver = NULL; | |
1554 | goto out; | |
1555 | } | |
1556 | } | |
1557 | ||
4fd5ea43 DW |
1558 | /* Check superblock checksum */ |
1559 | if (!jbd2_superblock_csum_verify(journal, sb)) { | |
a67c848a | 1560 | printk(KERN_ERR "JBD2: journal checksum error\n"); |
6a797d27 | 1561 | err = -EFSBADCRC; |
4fd5ea43 DW |
1562 | goto out; |
1563 | } | |
1564 | ||
1565 | /* Precompute checksum seed for all metadata */ | |
db9ee220 | 1566 | if (jbd2_journal_has_csum_v2or3(journal)) |
4fd5ea43 DW |
1567 | journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid, |
1568 | sizeof(sb->s_uuid)); | |
1569 | ||
25ed6e8a DW |
1570 | set_buffer_verified(bh); |
1571 | ||
470decc6 DK |
1572 | return 0; |
1573 | ||
1574 | out: | |
1575 | journal_fail_superblock(journal); | |
1576 | return err; | |
1577 | } | |
1578 | ||
1579 | /* | |
1580 | * Load the on-disk journal superblock and read the key fields into the | |
1581 | * journal_t. | |
1582 | */ | |
1583 | ||
1584 | static int load_superblock(journal_t *journal) | |
1585 | { | |
1586 | int err; | |
1587 | journal_superblock_t *sb; | |
1588 | ||
1589 | err = journal_get_superblock(journal); | |
1590 | if (err) | |
1591 | return err; | |
1592 | ||
1593 | sb = journal->j_superblock; | |
1594 | ||
1595 | journal->j_tail_sequence = be32_to_cpu(sb->s_sequence); | |
1596 | journal->j_tail = be32_to_cpu(sb->s_start); | |
1597 | journal->j_first = be32_to_cpu(sb->s_first); | |
1598 | journal->j_last = be32_to_cpu(sb->s_maxlen); | |
1599 | journal->j_errno = be32_to_cpu(sb->s_errno); | |
1600 | ||
1601 | return 0; | |
1602 | } | |
1603 | ||
1604 | ||
1605 | /** | |
f7f4bccb | 1606 | * int jbd2_journal_load() - Read journal from disk. |
470decc6 DK |
1607 | * @journal: Journal to act on. |
1608 | * | |
1609 | * Given a journal_t structure which tells us which disk blocks contain | |
1610 | * a journal, read the journal from disk to initialise the in-memory | |
1611 | * structures. | |
1612 | */ | |
f7f4bccb | 1613 | int jbd2_journal_load(journal_t *journal) |
470decc6 DK |
1614 | { |
1615 | int err; | |
1616 | journal_superblock_t *sb; | |
1617 | ||
1618 | err = load_superblock(journal); | |
1619 | if (err) | |
1620 | return err; | |
1621 | ||
1622 | sb = journal->j_superblock; | |
1623 | /* If this is a V2 superblock, then we have to check the | |
1624 | * features flags on it. */ | |
1625 | ||
1626 | if (journal->j_format_version >= 2) { | |
1627 | if ((sb->s_feature_ro_compat & | |
f7f4bccb | 1628 | ~cpu_to_be32(JBD2_KNOWN_ROCOMPAT_FEATURES)) || |
470decc6 | 1629 | (sb->s_feature_incompat & |
f7f4bccb | 1630 | ~cpu_to_be32(JBD2_KNOWN_INCOMPAT_FEATURES))) { |
f2a44523 EG |
1631 | printk(KERN_WARNING |
1632 | "JBD2: Unrecognised features on journal\n"); | |
470decc6 DK |
1633 | return -EINVAL; |
1634 | } | |
1635 | } | |
1636 | ||
d2eecb03 TT |
1637 | /* |
1638 | * Create a slab for this blocksize | |
1639 | */ | |
1640 | err = jbd2_journal_create_slab(be32_to_cpu(sb->s_blocksize)); | |
1641 | if (err) | |
1642 | return err; | |
1643 | ||
470decc6 DK |
1644 | /* Let the recovery code check whether it needs to recover any |
1645 | * data from the journal. */ | |
f7f4bccb | 1646 | if (jbd2_journal_recover(journal)) |
470decc6 DK |
1647 | goto recovery_error; |
1648 | ||
e6a47428 TT |
1649 | if (journal->j_failed_commit) { |
1650 | printk(KERN_ERR "JBD2: journal transaction %u on %s " | |
1651 | "is corrupt.\n", journal->j_failed_commit, | |
1652 | journal->j_devname); | |
6a797d27 | 1653 | return -EFSCORRUPTED; |
e6a47428 TT |
1654 | } |
1655 | ||
470decc6 DK |
1656 | /* OK, we've finished with the dynamic journal bits: |
1657 | * reinitialise the dynamic contents of the superblock in memory | |
1658 | * and reset them on disk. */ | |
1659 | if (journal_reset(journal)) | |
1660 | goto recovery_error; | |
1661 | ||
f7f4bccb MC |
1662 | journal->j_flags &= ~JBD2_ABORT; |
1663 | journal->j_flags |= JBD2_LOADED; | |
470decc6 DK |
1664 | return 0; |
1665 | ||
1666 | recovery_error: | |
f2a44523 | 1667 | printk(KERN_WARNING "JBD2: recovery failed\n"); |
470decc6 DK |
1668 | return -EIO; |
1669 | } | |
1670 | ||
1671 | /** | |
f7f4bccb | 1672 | * void jbd2_journal_destroy() - Release a journal_t structure. |
470decc6 DK |
1673 | * @journal: Journal to act on. |
1674 | * | |
1675 | * Release a journal_t structure once it is no longer in use by the | |
1676 | * journaled object. | |
44519faf | 1677 | * Return <0 if we couldn't clean up the journal. |
470decc6 | 1678 | */ |
44519faf | 1679 | int jbd2_journal_destroy(journal_t *journal) |
470decc6 | 1680 | { |
44519faf HK |
1681 | int err = 0; |
1682 | ||
470decc6 DK |
1683 | /* Wait for the commit thread to wake up and die. */ |
1684 | journal_kill_thread(journal); | |
1685 | ||
1686 | /* Force a final log commit */ | |
1687 | if (journal->j_running_transaction) | |
f7f4bccb | 1688 | jbd2_journal_commit_transaction(journal); |
470decc6 DK |
1689 | |
1690 | /* Force any old transactions to disk */ | |
1691 | ||
1692 | /* Totally anal locking here... */ | |
1693 | spin_lock(&journal->j_list_lock); | |
1694 | while (journal->j_checkpoint_transactions != NULL) { | |
1695 | spin_unlock(&journal->j_list_lock); | |
1a0d3786 | 1696 | mutex_lock(&journal->j_checkpoint_mutex); |
841df7df | 1697 | err = jbd2_log_do_checkpoint(journal); |
1a0d3786 | 1698 | mutex_unlock(&journal->j_checkpoint_mutex); |
841df7df JK |
1699 | /* |
1700 | * If checkpointing failed, just free the buffers to avoid | |
1701 | * looping forever | |
1702 | */ | |
1703 | if (err) { | |
1704 | jbd2_journal_destroy_checkpoint(journal); | |
1705 | spin_lock(&journal->j_list_lock); | |
1706 | break; | |
1707 | } | |
470decc6 DK |
1708 | spin_lock(&journal->j_list_lock); |
1709 | } | |
1710 | ||
1711 | J_ASSERT(journal->j_running_transaction == NULL); | |
1712 | J_ASSERT(journal->j_committing_transaction == NULL); | |
1713 | J_ASSERT(journal->j_checkpoint_transactions == NULL); | |
1714 | spin_unlock(&journal->j_list_lock); | |
1715 | ||
470decc6 | 1716 | if (journal->j_sb_buffer) { |
44519faf | 1717 | if (!is_journal_aborted(journal)) { |
a78bb11d | 1718 | mutex_lock(&journal->j_checkpoint_mutex); |
24bcc89c | 1719 | jbd2_mark_journal_empty(journal); |
a78bb11d JK |
1720 | mutex_unlock(&journal->j_checkpoint_mutex); |
1721 | } else | |
44519faf | 1722 | err = -EIO; |
470decc6 DK |
1723 | brelse(journal->j_sb_buffer); |
1724 | } | |
1725 | ||
8e85fb3f JL |
1726 | if (journal->j_proc_entry) |
1727 | jbd2_stats_proc_exit(journal); | |
d9f39d1e | 1728 | iput(journal->j_inode); |
470decc6 | 1729 | if (journal->j_revoke) |
f7f4bccb | 1730 | jbd2_journal_destroy_revoke(journal); |
01b5adce DW |
1731 | if (journal->j_chksum_driver) |
1732 | crypto_free_shash(journal->j_chksum_driver); | |
470decc6 DK |
1733 | kfree(journal->j_wbuf); |
1734 | kfree(journal); | |
44519faf HK |
1735 | |
1736 | return err; | |
470decc6 DK |
1737 | } |
1738 | ||
1739 | ||
1740 | /** | |
f7f4bccb | 1741 | *int jbd2_journal_check_used_features () - Check if features specified are used. |
470decc6 DK |
1742 | * @journal: Journal to check. |
1743 | * @compat: bitmask of compatible features | |
1744 | * @ro: bitmask of features that force read-only mount | |
1745 | * @incompat: bitmask of incompatible features | |
1746 | * | |
1747 | * Check whether the journal uses all of a given set of | |
1748 | * features. Return true (non-zero) if it does. | |
1749 | **/ | |
1750 | ||
f7f4bccb | 1751 | int jbd2_journal_check_used_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1752 | unsigned long ro, unsigned long incompat) |
1753 | { | |
1754 | journal_superblock_t *sb; | |
1755 | ||
1756 | if (!compat && !ro && !incompat) | |
1757 | return 1; | |
1113e1b5 PL |
1758 | /* Load journal superblock if it is not loaded yet. */ |
1759 | if (journal->j_format_version == 0 && | |
1760 | journal_get_superblock(journal) != 0) | |
1761 | return 0; | |
470decc6 DK |
1762 | if (journal->j_format_version == 1) |
1763 | return 0; | |
1764 | ||
1765 | sb = journal->j_superblock; | |
1766 | ||
1767 | if (((be32_to_cpu(sb->s_feature_compat) & compat) == compat) && | |
1768 | ((be32_to_cpu(sb->s_feature_ro_compat) & ro) == ro) && | |
1769 | ((be32_to_cpu(sb->s_feature_incompat) & incompat) == incompat)) | |
1770 | return 1; | |
1771 | ||
1772 | return 0; | |
1773 | } | |
1774 | ||
1775 | /** | |
f7f4bccb | 1776 | * int jbd2_journal_check_available_features() - Check feature set in journalling layer |
470decc6 DK |
1777 | * @journal: Journal to check. |
1778 | * @compat: bitmask of compatible features | |
1779 | * @ro: bitmask of features that force read-only mount | |
1780 | * @incompat: bitmask of incompatible features | |
1781 | * | |
1782 | * Check whether the journaling code supports the use of | |
1783 | * all of a given set of features on this journal. Return true | |
1784 | * (non-zero) if it can. */ | |
1785 | ||
f7f4bccb | 1786 | int jbd2_journal_check_available_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1787 | unsigned long ro, unsigned long incompat) |
1788 | { | |
470decc6 DK |
1789 | if (!compat && !ro && !incompat) |
1790 | return 1; | |
1791 | ||
470decc6 DK |
1792 | /* We can support any known requested features iff the |
1793 | * superblock is in version 2. Otherwise we fail to support any | |
1794 | * extended sb features. */ | |
1795 | ||
1796 | if (journal->j_format_version != 2) | |
1797 | return 0; | |
1798 | ||
f7f4bccb MC |
1799 | if ((compat & JBD2_KNOWN_COMPAT_FEATURES) == compat && |
1800 | (ro & JBD2_KNOWN_ROCOMPAT_FEATURES) == ro && | |
1801 | (incompat & JBD2_KNOWN_INCOMPAT_FEATURES) == incompat) | |
470decc6 DK |
1802 | return 1; |
1803 | ||
1804 | return 0; | |
1805 | } | |
1806 | ||
1807 | /** | |
f7f4bccb | 1808 | * int jbd2_journal_set_features () - Mark a given journal feature in the superblock |
470decc6 DK |
1809 | * @journal: Journal to act on. |
1810 | * @compat: bitmask of compatible features | |
1811 | * @ro: bitmask of features that force read-only mount | |
1812 | * @incompat: bitmask of incompatible features | |
1813 | * | |
1814 | * Mark a given journal feature as present on the | |
1815 | * superblock. Returns true if the requested features could be set. | |
1816 | * | |
1817 | */ | |
1818 | ||
f7f4bccb | 1819 | int jbd2_journal_set_features (journal_t *journal, unsigned long compat, |
470decc6 DK |
1820 | unsigned long ro, unsigned long incompat) |
1821 | { | |
25ed6e8a DW |
1822 | #define INCOMPAT_FEATURE_ON(f) \ |
1823 | ((incompat & (f)) && !(sb->s_feature_incompat & cpu_to_be32(f))) | |
1824 | #define COMPAT_FEATURE_ON(f) \ | |
1825 | ((compat & (f)) && !(sb->s_feature_compat & cpu_to_be32(f))) | |
470decc6 DK |
1826 | journal_superblock_t *sb; |
1827 | ||
f7f4bccb | 1828 | if (jbd2_journal_check_used_features(journal, compat, ro, incompat)) |
470decc6 DK |
1829 | return 1; |
1830 | ||
f7f4bccb | 1831 | if (!jbd2_journal_check_available_features(journal, compat, ro, incompat)) |
470decc6 DK |
1832 | return 0; |
1833 | ||
db9ee220 DW |
1834 | /* If enabling v2 checksums, turn on v3 instead */ |
1835 | if (incompat & JBD2_FEATURE_INCOMPAT_CSUM_V2) { | |
1836 | incompat &= ~JBD2_FEATURE_INCOMPAT_CSUM_V2; | |
1837 | incompat |= JBD2_FEATURE_INCOMPAT_CSUM_V3; | |
1838 | } | |
1839 | ||
1840 | /* Asking for checksumming v3 and v1? Only give them v3. */ | |
1841 | if (incompat & JBD2_FEATURE_INCOMPAT_CSUM_V3 && | |
25ed6e8a DW |
1842 | compat & JBD2_FEATURE_COMPAT_CHECKSUM) |
1843 | compat &= ~JBD2_FEATURE_COMPAT_CHECKSUM; | |
1844 | ||
470decc6 DK |
1845 | jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n", |
1846 | compat, ro, incompat); | |
1847 | ||
1848 | sb = journal->j_superblock; | |
1849 | ||
db9ee220 DW |
1850 | /* If enabling v3 checksums, update superblock */ |
1851 | if (INCOMPAT_FEATURE_ON(JBD2_FEATURE_INCOMPAT_CSUM_V3)) { | |
25ed6e8a DW |
1852 | sb->s_checksum_type = JBD2_CRC32C_CHKSUM; |
1853 | sb->s_feature_compat &= | |
1854 | ~cpu_to_be32(JBD2_FEATURE_COMPAT_CHECKSUM); | |
01b5adce DW |
1855 | |
1856 | /* Load the checksum driver */ | |
1857 | if (journal->j_chksum_driver == NULL) { | |
1858 | journal->j_chksum_driver = crypto_alloc_shash("crc32c", | |
1859 | 0, 0); | |
1860 | if (IS_ERR(journal->j_chksum_driver)) { | |
a67c848a | 1861 | printk(KERN_ERR "JBD2: Cannot load crc32c " |
01b5adce DW |
1862 | "driver.\n"); |
1863 | journal->j_chksum_driver = NULL; | |
1864 | return 0; | |
1865 | } | |
4fd5ea43 | 1866 | |
32f38691 | 1867 | /* Precompute checksum seed for all metadata */ |
4fd5ea43 DW |
1868 | journal->j_csum_seed = jbd2_chksum(journal, ~0, |
1869 | sb->s_uuid, | |
1870 | sizeof(sb->s_uuid)); | |
32f38691 | 1871 | } |
25ed6e8a DW |
1872 | } |
1873 | ||
1874 | /* If enabling v1 checksums, downgrade superblock */ | |
1875 | if (COMPAT_FEATURE_ON(JBD2_FEATURE_COMPAT_CHECKSUM)) | |
1876 | sb->s_feature_incompat &= | |
db9ee220 DW |
1877 | ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_CSUM_V2 | |
1878 | JBD2_FEATURE_INCOMPAT_CSUM_V3); | |
25ed6e8a | 1879 | |
470decc6 DK |
1880 | sb->s_feature_compat |= cpu_to_be32(compat); |
1881 | sb->s_feature_ro_compat |= cpu_to_be32(ro); | |
1882 | sb->s_feature_incompat |= cpu_to_be32(incompat); | |
1883 | ||
1884 | return 1; | |
25ed6e8a DW |
1885 | #undef COMPAT_FEATURE_ON |
1886 | #undef INCOMPAT_FEATURE_ON | |
470decc6 DK |
1887 | } |
1888 | ||
818d276c GS |
1889 | /* |
1890 | * jbd2_journal_clear_features () - Clear a given journal feature in the | |
1891 | * superblock | |
1892 | * @journal: Journal to act on. | |
1893 | * @compat: bitmask of compatible features | |
1894 | * @ro: bitmask of features that force read-only mount | |
1895 | * @incompat: bitmask of incompatible features | |
1896 | * | |
1897 | * Clear a given journal feature as present on the | |
1898 | * superblock. | |
1899 | */ | |
1900 | void jbd2_journal_clear_features(journal_t *journal, unsigned long compat, | |
1901 | unsigned long ro, unsigned long incompat) | |
1902 | { | |
1903 | journal_superblock_t *sb; | |
1904 | ||
1905 | jbd_debug(1, "Clear features 0x%lx/0x%lx/0x%lx\n", | |
1906 | compat, ro, incompat); | |
1907 | ||
1908 | sb = journal->j_superblock; | |
1909 | ||
1910 | sb->s_feature_compat &= ~cpu_to_be32(compat); | |
1911 | sb->s_feature_ro_compat &= ~cpu_to_be32(ro); | |
1912 | sb->s_feature_incompat &= ~cpu_to_be32(incompat); | |
1913 | } | |
1914 | EXPORT_SYMBOL(jbd2_journal_clear_features); | |
470decc6 | 1915 | |
470decc6 | 1916 | /** |
f7f4bccb | 1917 | * int jbd2_journal_flush () - Flush journal |
470decc6 DK |
1918 | * @journal: Journal to act on. |
1919 | * | |
1920 | * Flush all data for a given journal to disk and empty the journal. | |
1921 | * Filesystems can use this when remounting readonly to ensure that | |
1922 | * recovery does not need to happen on remount. | |
1923 | */ | |
1924 | ||
f7f4bccb | 1925 | int jbd2_journal_flush(journal_t *journal) |
470decc6 DK |
1926 | { |
1927 | int err = 0; | |
1928 | transaction_t *transaction = NULL; | |
470decc6 | 1929 | |
a931da6a | 1930 | write_lock(&journal->j_state_lock); |
470decc6 DK |
1931 | |
1932 | /* Force everything buffered to the log... */ | |
1933 | if (journal->j_running_transaction) { | |
1934 | transaction = journal->j_running_transaction; | |
f7f4bccb | 1935 | __jbd2_log_start_commit(journal, transaction->t_tid); |
470decc6 DK |
1936 | } else if (journal->j_committing_transaction) |
1937 | transaction = journal->j_committing_transaction; | |
1938 | ||
1939 | /* Wait for the log commit to complete... */ | |
1940 | if (transaction) { | |
1941 | tid_t tid = transaction->t_tid; | |
1942 | ||
a931da6a | 1943 | write_unlock(&journal->j_state_lock); |
f7f4bccb | 1944 | jbd2_log_wait_commit(journal, tid); |
470decc6 | 1945 | } else { |
a931da6a | 1946 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
1947 | } |
1948 | ||
1949 | /* ...and flush everything in the log out to disk. */ | |
1950 | spin_lock(&journal->j_list_lock); | |
1951 | while (!err && journal->j_checkpoint_transactions != NULL) { | |
1952 | spin_unlock(&journal->j_list_lock); | |
44519faf | 1953 | mutex_lock(&journal->j_checkpoint_mutex); |
f7f4bccb | 1954 | err = jbd2_log_do_checkpoint(journal); |
44519faf | 1955 | mutex_unlock(&journal->j_checkpoint_mutex); |
470decc6 DK |
1956 | spin_lock(&journal->j_list_lock); |
1957 | } | |
1958 | spin_unlock(&journal->j_list_lock); | |
44519faf HK |
1959 | |
1960 | if (is_journal_aborted(journal)) | |
1961 | return -EIO; | |
1962 | ||
a78bb11d | 1963 | mutex_lock(&journal->j_checkpoint_mutex); |
6f6a6fda JQ |
1964 | if (!err) { |
1965 | err = jbd2_cleanup_journal_tail(journal); | |
1966 | if (err < 0) { | |
1967 | mutex_unlock(&journal->j_checkpoint_mutex); | |
1968 | goto out; | |
1969 | } | |
1970 | err = 0; | |
1971 | } | |
470decc6 DK |
1972 | |
1973 | /* Finally, mark the journal as really needing no recovery. | |
1974 | * This sets s_start==0 in the underlying superblock, which is | |
1975 | * the magic code for a fully-recovered superblock. Any future | |
1976 | * commits of data to the journal will restore the current | |
1977 | * s_start value. */ | |
24bcc89c | 1978 | jbd2_mark_journal_empty(journal); |
a78bb11d | 1979 | mutex_unlock(&journal->j_checkpoint_mutex); |
a931da6a | 1980 | write_lock(&journal->j_state_lock); |
470decc6 DK |
1981 | J_ASSERT(!journal->j_running_transaction); |
1982 | J_ASSERT(!journal->j_committing_transaction); | |
1983 | J_ASSERT(!journal->j_checkpoint_transactions); | |
1984 | J_ASSERT(journal->j_head == journal->j_tail); | |
1985 | J_ASSERT(journal->j_tail_sequence == journal->j_transaction_sequence); | |
a931da6a | 1986 | write_unlock(&journal->j_state_lock); |
6f6a6fda JQ |
1987 | out: |
1988 | return err; | |
470decc6 DK |
1989 | } |
1990 | ||
1991 | /** | |
f7f4bccb | 1992 | * int jbd2_journal_wipe() - Wipe journal contents |
470decc6 DK |
1993 | * @journal: Journal to act on. |
1994 | * @write: flag (see below) | |
1995 | * | |
1996 | * Wipe out all of the contents of a journal, safely. This will produce | |
1997 | * a warning if the journal contains any valid recovery information. | |
f7f4bccb | 1998 | * Must be called between journal_init_*() and jbd2_journal_load(). |
470decc6 DK |
1999 | * |
2000 | * If 'write' is non-zero, then we wipe out the journal on disk; otherwise | |
2001 | * we merely suppress recovery. | |
2002 | */ | |
2003 | ||
f7f4bccb | 2004 | int jbd2_journal_wipe(journal_t *journal, int write) |
470decc6 | 2005 | { |
470decc6 DK |
2006 | int err = 0; |
2007 | ||
f7f4bccb | 2008 | J_ASSERT (!(journal->j_flags & JBD2_LOADED)); |
470decc6 DK |
2009 | |
2010 | err = load_superblock(journal); | |
2011 | if (err) | |
2012 | return err; | |
2013 | ||
470decc6 DK |
2014 | if (!journal->j_tail) |
2015 | goto no_recovery; | |
2016 | ||
f2a44523 | 2017 | printk(KERN_WARNING "JBD2: %s recovery information on journal\n", |
470decc6 DK |
2018 | write ? "Clearing" : "Ignoring"); |
2019 | ||
f7f4bccb | 2020 | err = jbd2_journal_skip_recovery(journal); |
a78bb11d JK |
2021 | if (write) { |
2022 | /* Lock to make assertions happy... */ | |
2023 | mutex_lock(&journal->j_checkpoint_mutex); | |
24bcc89c | 2024 | jbd2_mark_journal_empty(journal); |
a78bb11d JK |
2025 | mutex_unlock(&journal->j_checkpoint_mutex); |
2026 | } | |
470decc6 DK |
2027 | |
2028 | no_recovery: | |
2029 | return err; | |
2030 | } | |
2031 | ||
470decc6 DK |
2032 | /* |
2033 | * Journal abort has very specific semantics, which we describe | |
2034 | * for journal abort. | |
2035 | * | |
bfcd3555 | 2036 | * Two internal functions, which provide abort to the jbd layer |
470decc6 DK |
2037 | * itself are here. |
2038 | */ | |
2039 | ||
2040 | /* | |
2041 | * Quick version for internal journal use (doesn't lock the journal). | |
2042 | * Aborts hard --- we mark the abort as occurred, but do _nothing_ else, | |
2043 | * and don't attempt to make any other journal updates. | |
2044 | */ | |
f7f4bccb | 2045 | void __jbd2_journal_abort_hard(journal_t *journal) |
470decc6 DK |
2046 | { |
2047 | transaction_t *transaction; | |
470decc6 | 2048 | |
f7f4bccb | 2049 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
2050 | return; |
2051 | ||
2052 | printk(KERN_ERR "Aborting journal on device %s.\n", | |
05496769 | 2053 | journal->j_devname); |
470decc6 | 2054 | |
a931da6a | 2055 | write_lock(&journal->j_state_lock); |
f7f4bccb | 2056 | journal->j_flags |= JBD2_ABORT; |
470decc6 DK |
2057 | transaction = journal->j_running_transaction; |
2058 | if (transaction) | |
f7f4bccb | 2059 | __jbd2_log_start_commit(journal, transaction->t_tid); |
a931da6a | 2060 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
2061 | } |
2062 | ||
2063 | /* Soft abort: record the abort error status in the journal superblock, | |
2064 | * but don't do any other IO. */ | |
2065 | static void __journal_abort_soft (journal_t *journal, int errno) | |
2066 | { | |
f7f4bccb | 2067 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
2068 | return; |
2069 | ||
2070 | if (!journal->j_errno) | |
2071 | journal->j_errno = errno; | |
2072 | ||
f7f4bccb | 2073 | __jbd2_journal_abort_hard(journal); |
470decc6 | 2074 | |
4327ba52 | 2075 | if (errno) { |
24bcc89c | 2076 | jbd2_journal_update_sb_errno(journal); |
4327ba52 DJ |
2077 | write_lock(&journal->j_state_lock); |
2078 | journal->j_flags |= JBD2_REC_ERR; | |
2079 | write_unlock(&journal->j_state_lock); | |
2080 | } | |
470decc6 DK |
2081 | } |
2082 | ||
2083 | /** | |
f7f4bccb | 2084 | * void jbd2_journal_abort () - Shutdown the journal immediately. |
470decc6 DK |
2085 | * @journal: the journal to shutdown. |
2086 | * @errno: an error number to record in the journal indicating | |
2087 | * the reason for the shutdown. | |
2088 | * | |
2089 | * Perform a complete, immediate shutdown of the ENTIRE | |
2090 | * journal (not of a single transaction). This operation cannot be | |
2091 | * undone without closing and reopening the journal. | |
2092 | * | |
f7f4bccb | 2093 | * The jbd2_journal_abort function is intended to support higher level error |
470decc6 DK |
2094 | * recovery mechanisms such as the ext2/ext3 remount-readonly error |
2095 | * mode. | |
2096 | * | |
2097 | * Journal abort has very specific semantics. Any existing dirty, | |
2098 | * unjournaled buffers in the main filesystem will still be written to | |
2099 | * disk by bdflush, but the journaling mechanism will be suspended | |
2100 | * immediately and no further transaction commits will be honoured. | |
2101 | * | |
2102 | * Any dirty, journaled buffers will be written back to disk without | |
2103 | * hitting the journal. Atomicity cannot be guaranteed on an aborted | |
2104 | * filesystem, but we _do_ attempt to leave as much data as possible | |
2105 | * behind for fsck to use for cleanup. | |
2106 | * | |
2107 | * Any attempt to get a new transaction handle on a journal which is in | |
2108 | * ABORT state will just result in an -EROFS error return. A | |
f7f4bccb | 2109 | * jbd2_journal_stop on an existing handle will return -EIO if we have |
470decc6 DK |
2110 | * entered abort state during the update. |
2111 | * | |
2112 | * Recursive transactions are not disturbed by journal abort until the | |
f7f4bccb | 2113 | * final jbd2_journal_stop, which will receive the -EIO error. |
470decc6 | 2114 | * |
f7f4bccb | 2115 | * Finally, the jbd2_journal_abort call allows the caller to supply an errno |
470decc6 DK |
2116 | * which will be recorded (if possible) in the journal superblock. This |
2117 | * allows a client to record failure conditions in the middle of a | |
2118 | * transaction without having to complete the transaction to record the | |
2119 | * failure to disk. ext3_error, for example, now uses this | |
2120 | * functionality. | |
2121 | * | |
2122 | * Errors which originate from within the journaling layer will NOT | |
2123 | * supply an errno; a null errno implies that absolutely no further | |
2124 | * writes are done to the journal (unless there are any already in | |
2125 | * progress). | |
2126 | * | |
2127 | */ | |
2128 | ||
f7f4bccb | 2129 | void jbd2_journal_abort(journal_t *journal, int errno) |
470decc6 DK |
2130 | { |
2131 | __journal_abort_soft(journal, errno); | |
2132 | } | |
2133 | ||
2134 | /** | |
f7f4bccb | 2135 | * int jbd2_journal_errno () - returns the journal's error state. |
470decc6 DK |
2136 | * @journal: journal to examine. |
2137 | * | |
bfcd3555 | 2138 | * This is the errno number set with jbd2_journal_abort(), the last |
470decc6 DK |
2139 | * time the journal was mounted - if the journal was stopped |
2140 | * without calling abort this will be 0. | |
2141 | * | |
2142 | * If the journal has been aborted on this mount time -EROFS will | |
2143 | * be returned. | |
2144 | */ | |
f7f4bccb | 2145 | int jbd2_journal_errno(journal_t *journal) |
470decc6 DK |
2146 | { |
2147 | int err; | |
2148 | ||
a931da6a | 2149 | read_lock(&journal->j_state_lock); |
f7f4bccb | 2150 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
2151 | err = -EROFS; |
2152 | else | |
2153 | err = journal->j_errno; | |
a931da6a | 2154 | read_unlock(&journal->j_state_lock); |
470decc6 DK |
2155 | return err; |
2156 | } | |
2157 | ||
2158 | /** | |
f7f4bccb | 2159 | * int jbd2_journal_clear_err () - clears the journal's error state |
470decc6 DK |
2160 | * @journal: journal to act on. |
2161 | * | |
bfcd3555 | 2162 | * An error must be cleared or acked to take a FS out of readonly |
470decc6 DK |
2163 | * mode. |
2164 | */ | |
f7f4bccb | 2165 | int jbd2_journal_clear_err(journal_t *journal) |
470decc6 DK |
2166 | { |
2167 | int err = 0; | |
2168 | ||
a931da6a | 2169 | write_lock(&journal->j_state_lock); |
f7f4bccb | 2170 | if (journal->j_flags & JBD2_ABORT) |
470decc6 DK |
2171 | err = -EROFS; |
2172 | else | |
2173 | journal->j_errno = 0; | |
a931da6a | 2174 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
2175 | return err; |
2176 | } | |
2177 | ||
2178 | /** | |
f7f4bccb | 2179 | * void jbd2_journal_ack_err() - Ack journal err. |
470decc6 DK |
2180 | * @journal: journal to act on. |
2181 | * | |
bfcd3555 | 2182 | * An error must be cleared or acked to take a FS out of readonly |
470decc6 DK |
2183 | * mode. |
2184 | */ | |
f7f4bccb | 2185 | void jbd2_journal_ack_err(journal_t *journal) |
470decc6 | 2186 | { |
a931da6a | 2187 | write_lock(&journal->j_state_lock); |
470decc6 | 2188 | if (journal->j_errno) |
f7f4bccb | 2189 | journal->j_flags |= JBD2_ACK_ERR; |
a931da6a | 2190 | write_unlock(&journal->j_state_lock); |
470decc6 DK |
2191 | } |
2192 | ||
f7f4bccb | 2193 | int jbd2_journal_blocks_per_page(struct inode *inode) |
470decc6 DK |
2194 | { |
2195 | return 1 << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); | |
2196 | } | |
2197 | ||
b517bea1 ZB |
2198 | /* |
2199 | * helper functions to deal with 32 or 64bit block numbers. | |
2200 | */ | |
2201 | size_t journal_tag_bytes(journal_t *journal) | |
2202 | { | |
db9ee220 DW |
2203 | size_t sz; |
2204 | ||
56316a0d | 2205 | if (jbd2_has_feature_csum3(journal)) |
db9ee220 DW |
2206 | return sizeof(journal_block_tag3_t); |
2207 | ||
2208 | sz = sizeof(journal_block_tag_t); | |
c3900875 | 2209 | |
56316a0d | 2210 | if (jbd2_has_feature_csum2(journal)) |
db9ee220 | 2211 | sz += sizeof(__u16); |
c3900875 | 2212 | |
56316a0d | 2213 | if (jbd2_has_feature_64bit(journal)) |
db9ee220 | 2214 | return sz; |
b517bea1 | 2215 | else |
db9ee220 | 2216 | return sz - sizeof(__u32); |
b517bea1 ZB |
2217 | } |
2218 | ||
d2eecb03 TT |
2219 | /* |
2220 | * JBD memory management | |
2221 | * | |
2222 | * These functions are used to allocate block-sized chunks of memory | |
2223 | * used for making copies of buffer_head data. Very often it will be | |
2224 | * page-sized chunks of data, but sometimes it will be in | |
2225 | * sub-page-size chunks. (For example, 16k pages on Power systems | |
2226 | * with a 4k block file system.) For blocks smaller than a page, we | |
2227 | * use a SLAB allocator. There are slab caches for each block size, | |
2228 | * which are allocated at mount time, if necessary, and we only free | |
2229 | * (all of) the slab caches when/if the jbd2 module is unloaded. For | |
2230 | * this reason we don't need to a mutex to protect access to | |
2231 | * jbd2_slab[] allocating or releasing memory; only in | |
2232 | * jbd2_journal_create_slab(). | |
2233 | */ | |
2234 | #define JBD2_MAX_SLABS 8 | |
2235 | static struct kmem_cache *jbd2_slab[JBD2_MAX_SLABS]; | |
d2eecb03 TT |
2236 | |
2237 | static const char *jbd2_slab_names[JBD2_MAX_SLABS] = { | |
2238 | "jbd2_1k", "jbd2_2k", "jbd2_4k", "jbd2_8k", | |
2239 | "jbd2_16k", "jbd2_32k", "jbd2_64k", "jbd2_128k" | |
2240 | }; | |
2241 | ||
2242 | ||
2243 | static void jbd2_journal_destroy_slabs(void) | |
2244 | { | |
2245 | int i; | |
2246 | ||
2247 | for (i = 0; i < JBD2_MAX_SLABS; i++) { | |
2248 | if (jbd2_slab[i]) | |
2249 | kmem_cache_destroy(jbd2_slab[i]); | |
2250 | jbd2_slab[i] = NULL; | |
2251 | } | |
2252 | } | |
2253 | ||
2254 | static int jbd2_journal_create_slab(size_t size) | |
2255 | { | |
51dfacde | 2256 | static DEFINE_MUTEX(jbd2_slab_create_mutex); |
d2eecb03 TT |
2257 | int i = order_base_2(size) - 10; |
2258 | size_t slab_size; | |
2259 | ||
2260 | if (size == PAGE_SIZE) | |
2261 | return 0; | |
2262 | ||
2263 | if (i >= JBD2_MAX_SLABS) | |
2264 | return -EINVAL; | |
2265 | ||
2266 | if (unlikely(i < 0)) | |
2267 | i = 0; | |
51dfacde | 2268 | mutex_lock(&jbd2_slab_create_mutex); |
d2eecb03 | 2269 | if (jbd2_slab[i]) { |
51dfacde | 2270 | mutex_unlock(&jbd2_slab_create_mutex); |
d2eecb03 TT |
2271 | return 0; /* Already created */ |
2272 | } | |
2273 | ||
2274 | slab_size = 1 << (i+10); | |
2275 | jbd2_slab[i] = kmem_cache_create(jbd2_slab_names[i], slab_size, | |
2276 | slab_size, 0, NULL); | |
51dfacde | 2277 | mutex_unlock(&jbd2_slab_create_mutex); |
d2eecb03 TT |
2278 | if (!jbd2_slab[i]) { |
2279 | printk(KERN_EMERG "JBD2: no memory for jbd2_slab cache\n"); | |
2280 | return -ENOMEM; | |
2281 | } | |
2282 | return 0; | |
2283 | } | |
2284 | ||
2285 | static struct kmem_cache *get_slab(size_t size) | |
2286 | { | |
2287 | int i = order_base_2(size) - 10; | |
2288 | ||
2289 | BUG_ON(i >= JBD2_MAX_SLABS); | |
2290 | if (unlikely(i < 0)) | |
2291 | i = 0; | |
8ac97b74 | 2292 | BUG_ON(jbd2_slab[i] == NULL); |
d2eecb03 TT |
2293 | return jbd2_slab[i]; |
2294 | } | |
2295 | ||
2296 | void *jbd2_alloc(size_t size, gfp_t flags) | |
2297 | { | |
2298 | void *ptr; | |
2299 | ||
2300 | BUG_ON(size & (size-1)); /* Must be a power of 2 */ | |
2301 | ||
2302 | flags |= __GFP_REPEAT; | |
2303 | if (size == PAGE_SIZE) | |
2304 | ptr = (void *)__get_free_pages(flags, 0); | |
2305 | else if (size > PAGE_SIZE) { | |
2306 | int order = get_order(size); | |
2307 | ||
2308 | if (order < 3) | |
2309 | ptr = (void *)__get_free_pages(flags, order); | |
2310 | else | |
2311 | ptr = vmalloc(size); | |
2312 | } else | |
2313 | ptr = kmem_cache_alloc(get_slab(size), flags); | |
2314 | ||
2315 | /* Check alignment; SLUB has gotten this wrong in the past, | |
2316 | * and this can lead to user data corruption! */ | |
2317 | BUG_ON(((unsigned long) ptr) & (size-1)); | |
2318 | ||
2319 | return ptr; | |
2320 | } | |
2321 | ||
2322 | void jbd2_free(void *ptr, size_t size) | |
2323 | { | |
2324 | if (size == PAGE_SIZE) { | |
2325 | free_pages((unsigned long)ptr, 0); | |
2326 | return; | |
2327 | } | |
2328 | if (size > PAGE_SIZE) { | |
2329 | int order = get_order(size); | |
2330 | ||
2331 | if (order < 3) | |
2332 | free_pages((unsigned long)ptr, order); | |
2333 | else | |
2334 | vfree(ptr); | |
2335 | return; | |
2336 | } | |
2337 | kmem_cache_free(get_slab(size), ptr); | |
2338 | }; | |
2339 | ||
470decc6 DK |
2340 | /* |
2341 | * Journal_head storage management | |
2342 | */ | |
e18b890b | 2343 | static struct kmem_cache *jbd2_journal_head_cache; |
e23291b9 | 2344 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
2345 | static atomic_t nr_journal_heads = ATOMIC_INIT(0); |
2346 | #endif | |
2347 | ||
4185a2ac | 2348 | static int jbd2_journal_init_journal_head_cache(void) |
470decc6 DK |
2349 | { |
2350 | int retval; | |
2351 | ||
1076d17a | 2352 | J_ASSERT(jbd2_journal_head_cache == NULL); |
a920e941 | 2353 | jbd2_journal_head_cache = kmem_cache_create("jbd2_journal_head", |
470decc6 DK |
2354 | sizeof(struct journal_head), |
2355 | 0, /* offset */ | |
de92c8ca | 2356 | SLAB_TEMPORARY | SLAB_DESTROY_BY_RCU, |
20c2df83 | 2357 | NULL); /* ctor */ |
470decc6 | 2358 | retval = 0; |
1076d17a | 2359 | if (!jbd2_journal_head_cache) { |
470decc6 | 2360 | retval = -ENOMEM; |
f2a44523 | 2361 | printk(KERN_EMERG "JBD2: no memory for journal_head cache\n"); |
470decc6 DK |
2362 | } |
2363 | return retval; | |
2364 | } | |
2365 | ||
4185a2ac | 2366 | static void jbd2_journal_destroy_journal_head_cache(void) |
470decc6 | 2367 | { |
8a9362eb DG |
2368 | if (jbd2_journal_head_cache) { |
2369 | kmem_cache_destroy(jbd2_journal_head_cache); | |
2370 | jbd2_journal_head_cache = NULL; | |
2371 | } | |
470decc6 DK |
2372 | } |
2373 | ||
2374 | /* | |
2375 | * journal_head splicing and dicing | |
2376 | */ | |
2377 | static struct journal_head *journal_alloc_journal_head(void) | |
2378 | { | |
2379 | struct journal_head *ret; | |
470decc6 | 2380 | |
e23291b9 | 2381 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
2382 | atomic_inc(&nr_journal_heads); |
2383 | #endif | |
5d9cf9c6 | 2384 | ret = kmem_cache_zalloc(jbd2_journal_head_cache, GFP_NOFS); |
1076d17a | 2385 | if (!ret) { |
470decc6 | 2386 | jbd_debug(1, "out of memory for journal_head\n"); |
670be5a7 | 2387 | pr_notice_ratelimited("ENOMEM in %s, retrying.\n", __func__); |
7b506b10 MH |
2388 | ret = kmem_cache_zalloc(jbd2_journal_head_cache, |
2389 | GFP_NOFS | __GFP_NOFAIL); | |
470decc6 DK |
2390 | } |
2391 | return ret; | |
2392 | } | |
2393 | ||
2394 | static void journal_free_journal_head(struct journal_head *jh) | |
2395 | { | |
e23291b9 | 2396 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 | 2397 | atomic_dec(&nr_journal_heads); |
cd02ff0b | 2398 | memset(jh, JBD2_POISON_FREE, sizeof(*jh)); |
470decc6 | 2399 | #endif |
f7f4bccb | 2400 | kmem_cache_free(jbd2_journal_head_cache, jh); |
470decc6 DK |
2401 | } |
2402 | ||
2403 | /* | |
2404 | * A journal_head is attached to a buffer_head whenever JBD has an | |
2405 | * interest in the buffer. | |
2406 | * | |
2407 | * Whenever a buffer has an attached journal_head, its ->b_state:BH_JBD bit | |
2408 | * is set. This bit is tested in core kernel code where we need to take | |
2409 | * JBD-specific actions. Testing the zeroness of ->b_private is not reliable | |
2410 | * there. | |
2411 | * | |
2412 | * When a buffer has its BH_JBD bit set, its ->b_count is elevated by one. | |
2413 | * | |
2414 | * When a buffer has its BH_JBD bit set it is immune from being released by | |
2415 | * core kernel code, mainly via ->b_count. | |
2416 | * | |
de1b7941 JK |
2417 | * A journal_head is detached from its buffer_head when the journal_head's |
2418 | * b_jcount reaches zero. Running transaction (b_transaction) and checkpoint | |
2419 | * transaction (b_cp_transaction) hold their references to b_jcount. | |
470decc6 DK |
2420 | * |
2421 | * Various places in the kernel want to attach a journal_head to a buffer_head | |
2422 | * _before_ attaching the journal_head to a transaction. To protect the | |
f7f4bccb | 2423 | * journal_head in this situation, jbd2_journal_add_journal_head elevates the |
470decc6 | 2424 | * journal_head's b_jcount refcount by one. The caller must call |
f7f4bccb | 2425 | * jbd2_journal_put_journal_head() to undo this. |
470decc6 DK |
2426 | * |
2427 | * So the typical usage would be: | |
2428 | * | |
2429 | * (Attach a journal_head if needed. Increments b_jcount) | |
f7f4bccb | 2430 | * struct journal_head *jh = jbd2_journal_add_journal_head(bh); |
470decc6 | 2431 | * ... |
de1b7941 JK |
2432 | * (Get another reference for transaction) |
2433 | * jbd2_journal_grab_journal_head(bh); | |
470decc6 | 2434 | * jh->b_transaction = xxx; |
de1b7941 | 2435 | * (Put original reference) |
f7f4bccb | 2436 | * jbd2_journal_put_journal_head(jh); |
470decc6 DK |
2437 | */ |
2438 | ||
2439 | /* | |
2440 | * Give a buffer_head a journal_head. | |
2441 | * | |
470decc6 DK |
2442 | * May sleep. |
2443 | */ | |
f7f4bccb | 2444 | struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh) |
470decc6 DK |
2445 | { |
2446 | struct journal_head *jh; | |
2447 | struct journal_head *new_jh = NULL; | |
2448 | ||
2449 | repeat: | |
5d9cf9c6 | 2450 | if (!buffer_jbd(bh)) |
470decc6 | 2451 | new_jh = journal_alloc_journal_head(); |
470decc6 DK |
2452 | |
2453 | jbd_lock_bh_journal_head(bh); | |
2454 | if (buffer_jbd(bh)) { | |
2455 | jh = bh2jh(bh); | |
2456 | } else { | |
2457 | J_ASSERT_BH(bh, | |
2458 | (atomic_read(&bh->b_count) > 0) || | |
2459 | (bh->b_page && bh->b_page->mapping)); | |
2460 | ||
2461 | if (!new_jh) { | |
2462 | jbd_unlock_bh_journal_head(bh); | |
2463 | goto repeat; | |
2464 | } | |
2465 | ||
2466 | jh = new_jh; | |
2467 | new_jh = NULL; /* We consumed it */ | |
2468 | set_buffer_jbd(bh); | |
2469 | bh->b_private = jh; | |
2470 | jh->b_bh = bh; | |
2471 | get_bh(bh); | |
2472 | BUFFER_TRACE(bh, "added journal_head"); | |
2473 | } | |
2474 | jh->b_jcount++; | |
2475 | jbd_unlock_bh_journal_head(bh); | |
2476 | if (new_jh) | |
2477 | journal_free_journal_head(new_jh); | |
2478 | return bh->b_private; | |
2479 | } | |
2480 | ||
2481 | /* | |
2482 | * Grab a ref against this buffer_head's journal_head. If it ended up not | |
2483 | * having a journal_head, return NULL | |
2484 | */ | |
f7f4bccb | 2485 | struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh) |
470decc6 DK |
2486 | { |
2487 | struct journal_head *jh = NULL; | |
2488 | ||
2489 | jbd_lock_bh_journal_head(bh); | |
2490 | if (buffer_jbd(bh)) { | |
2491 | jh = bh2jh(bh); | |
2492 | jh->b_jcount++; | |
2493 | } | |
2494 | jbd_unlock_bh_journal_head(bh); | |
2495 | return jh; | |
2496 | } | |
2497 | ||
2498 | static void __journal_remove_journal_head(struct buffer_head *bh) | |
2499 | { | |
2500 | struct journal_head *jh = bh2jh(bh); | |
2501 | ||
2502 | J_ASSERT_JH(jh, jh->b_jcount >= 0); | |
de1b7941 JK |
2503 | J_ASSERT_JH(jh, jh->b_transaction == NULL); |
2504 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); | |
2505 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); | |
2506 | J_ASSERT_JH(jh, jh->b_jlist == BJ_None); | |
2507 | J_ASSERT_BH(bh, buffer_jbd(bh)); | |
2508 | J_ASSERT_BH(bh, jh2bh(jh) == bh); | |
2509 | BUFFER_TRACE(bh, "remove journal_head"); | |
2510 | if (jh->b_frozen_data) { | |
2511 | printk(KERN_WARNING "%s: freeing b_frozen_data\n", __func__); | |
2512 | jbd2_free(jh->b_frozen_data, bh->b_size); | |
470decc6 | 2513 | } |
de1b7941 JK |
2514 | if (jh->b_committed_data) { |
2515 | printk(KERN_WARNING "%s: freeing b_committed_data\n", __func__); | |
2516 | jbd2_free(jh->b_committed_data, bh->b_size); | |
2517 | } | |
2518 | bh->b_private = NULL; | |
2519 | jh->b_bh = NULL; /* debug, really */ | |
2520 | clear_buffer_jbd(bh); | |
2521 | journal_free_journal_head(jh); | |
470decc6 DK |
2522 | } |
2523 | ||
2524 | /* | |
de1b7941 | 2525 | * Drop a reference on the passed journal_head. If it fell to zero then |
470decc6 DK |
2526 | * release the journal_head from the buffer_head. |
2527 | */ | |
f7f4bccb | 2528 | void jbd2_journal_put_journal_head(struct journal_head *jh) |
470decc6 DK |
2529 | { |
2530 | struct buffer_head *bh = jh2bh(jh); | |
2531 | ||
2532 | jbd_lock_bh_journal_head(bh); | |
2533 | J_ASSERT_JH(jh, jh->b_jcount > 0); | |
2534 | --jh->b_jcount; | |
de1b7941 | 2535 | if (!jh->b_jcount) { |
470decc6 | 2536 | __journal_remove_journal_head(bh); |
de1b7941 | 2537 | jbd_unlock_bh_journal_head(bh); |
470decc6 | 2538 | __brelse(bh); |
de1b7941 JK |
2539 | } else |
2540 | jbd_unlock_bh_journal_head(bh); | |
470decc6 DK |
2541 | } |
2542 | ||
c851ed54 JK |
2543 | /* |
2544 | * Initialize jbd inode head | |
2545 | */ | |
2546 | void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode) | |
2547 | { | |
2548 | jinode->i_transaction = NULL; | |
2549 | jinode->i_next_transaction = NULL; | |
2550 | jinode->i_vfs_inode = inode; | |
2551 | jinode->i_flags = 0; | |
2552 | INIT_LIST_HEAD(&jinode->i_list); | |
2553 | } | |
2554 | ||
2555 | /* | |
2556 | * Function to be called before we start removing inode from memory (i.e., | |
2557 | * clear_inode() is a fine place to be called from). It removes inode from | |
2558 | * transaction's lists. | |
2559 | */ | |
2560 | void jbd2_journal_release_jbd_inode(journal_t *journal, | |
2561 | struct jbd2_inode *jinode) | |
2562 | { | |
c851ed54 JK |
2563 | if (!journal) |
2564 | return; | |
2565 | restart: | |
2566 | spin_lock(&journal->j_list_lock); | |
2567 | /* Is commit writing out inode - we have to wait */ | |
39e3ac25 | 2568 | if (test_bit(__JI_COMMIT_RUNNING, &jinode->i_flags)) { |
c851ed54 JK |
2569 | wait_queue_head_t *wq; |
2570 | DEFINE_WAIT_BIT(wait, &jinode->i_flags, __JI_COMMIT_RUNNING); | |
2571 | wq = bit_waitqueue(&jinode->i_flags, __JI_COMMIT_RUNNING); | |
2572 | prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE); | |
2573 | spin_unlock(&journal->j_list_lock); | |
2574 | schedule(); | |
2575 | finish_wait(wq, &wait.wait); | |
2576 | goto restart; | |
2577 | } | |
2578 | ||
c851ed54 JK |
2579 | if (jinode->i_transaction) { |
2580 | list_del(&jinode->i_list); | |
2581 | jinode->i_transaction = NULL; | |
2582 | } | |
2583 | spin_unlock(&journal->j_list_lock); | |
2584 | } | |
2585 | ||
470decc6 | 2586 | |
8e85fb3f JL |
2587 | #ifdef CONFIG_PROC_FS |
2588 | ||
2589 | #define JBD2_STATS_PROC_NAME "fs/jbd2" | |
2590 | ||
2591 | static void __init jbd2_create_jbd_stats_proc_entry(void) | |
2592 | { | |
2593 | proc_jbd2_stats = proc_mkdir(JBD2_STATS_PROC_NAME, NULL); | |
2594 | } | |
2595 | ||
2596 | static void __exit jbd2_remove_jbd_stats_proc_entry(void) | |
2597 | { | |
2598 | if (proc_jbd2_stats) | |
2599 | remove_proc_entry(JBD2_STATS_PROC_NAME, NULL); | |
2600 | } | |
2601 | ||
2602 | #else | |
2603 | ||
2604 | #define jbd2_create_jbd_stats_proc_entry() do {} while (0) | |
2605 | #define jbd2_remove_jbd_stats_proc_entry() do {} while (0) | |
2606 | ||
2607 | #endif | |
2608 | ||
8aefcd55 | 2609 | struct kmem_cache *jbd2_handle_cache, *jbd2_inode_cache; |
470decc6 | 2610 | |
4185a2ac | 2611 | static int __init jbd2_journal_init_handle_cache(void) |
470decc6 | 2612 | { |
8aefcd55 | 2613 | jbd2_handle_cache = KMEM_CACHE(jbd2_journal_handle, SLAB_TEMPORARY); |
f7f4bccb | 2614 | if (jbd2_handle_cache == NULL) { |
8aefcd55 TT |
2615 | printk(KERN_EMERG "JBD2: failed to create handle cache\n"); |
2616 | return -ENOMEM; | |
2617 | } | |
2618 | jbd2_inode_cache = KMEM_CACHE(jbd2_inode, 0); | |
2619 | if (jbd2_inode_cache == NULL) { | |
2620 | printk(KERN_EMERG "JBD2: failed to create inode cache\n"); | |
2621 | kmem_cache_destroy(jbd2_handle_cache); | |
470decc6 DK |
2622 | return -ENOMEM; |
2623 | } | |
2624 | return 0; | |
2625 | } | |
2626 | ||
f7f4bccb | 2627 | static void jbd2_journal_destroy_handle_cache(void) |
470decc6 | 2628 | { |
f7f4bccb MC |
2629 | if (jbd2_handle_cache) |
2630 | kmem_cache_destroy(jbd2_handle_cache); | |
8aefcd55 TT |
2631 | if (jbd2_inode_cache) |
2632 | kmem_cache_destroy(jbd2_inode_cache); | |
2633 | ||
470decc6 DK |
2634 | } |
2635 | ||
2636 | /* | |
2637 | * Module startup and shutdown | |
2638 | */ | |
2639 | ||
2640 | static int __init journal_init_caches(void) | |
2641 | { | |
2642 | int ret; | |
2643 | ||
f7f4bccb | 2644 | ret = jbd2_journal_init_revoke_caches(); |
470decc6 | 2645 | if (ret == 0) |
4185a2ac | 2646 | ret = jbd2_journal_init_journal_head_cache(); |
470decc6 | 2647 | if (ret == 0) |
4185a2ac | 2648 | ret = jbd2_journal_init_handle_cache(); |
470decc6 | 2649 | if (ret == 0) |
0c2022ec | 2650 | ret = jbd2_journal_init_transaction_cache(); |
470decc6 DK |
2651 | return ret; |
2652 | } | |
2653 | ||
f7f4bccb | 2654 | static void jbd2_journal_destroy_caches(void) |
470decc6 | 2655 | { |
f7f4bccb | 2656 | jbd2_journal_destroy_revoke_caches(); |
4185a2ac | 2657 | jbd2_journal_destroy_journal_head_cache(); |
f7f4bccb | 2658 | jbd2_journal_destroy_handle_cache(); |
0c2022ec | 2659 | jbd2_journal_destroy_transaction_cache(); |
d2eecb03 | 2660 | jbd2_journal_destroy_slabs(); |
470decc6 DK |
2661 | } |
2662 | ||
2663 | static int __init journal_init(void) | |
2664 | { | |
2665 | int ret; | |
2666 | ||
2667 | BUILD_BUG_ON(sizeof(struct journal_superblock_s) != 1024); | |
2668 | ||
2669 | ret = journal_init_caches(); | |
620de4e1 | 2670 | if (ret == 0) { |
620de4e1 DG |
2671 | jbd2_create_jbd_stats_proc_entry(); |
2672 | } else { | |
f7f4bccb | 2673 | jbd2_journal_destroy_caches(); |
620de4e1 | 2674 | } |
470decc6 DK |
2675 | return ret; |
2676 | } | |
2677 | ||
2678 | static void __exit journal_exit(void) | |
2679 | { | |
e23291b9 | 2680 | #ifdef CONFIG_JBD2_DEBUG |
470decc6 DK |
2681 | int n = atomic_read(&nr_journal_heads); |
2682 | if (n) | |
75685071 | 2683 | printk(KERN_ERR "JBD2: leaked %d journal_heads!\n", n); |
470decc6 | 2684 | #endif |
8e85fb3f | 2685 | jbd2_remove_jbd_stats_proc_entry(); |
f7f4bccb | 2686 | jbd2_journal_destroy_caches(); |
470decc6 DK |
2687 | } |
2688 | ||
2689 | MODULE_LICENSE("GPL"); | |
2690 | module_init(journal_init); | |
2691 | module_exit(journal_exit); | |
2692 |