| blob | f03597b05248d044f2f7b542e2ebfc6148a970b4 |
1 /*
2 ** Write ahead logging implementation copyright Chris Mason 2000
3 **
4 ** The background commits make this code very interelated, and
5 ** overly complex. I need to rethink things a bit....The major players:
6 **
7 ** journal_begin -- call with the number of blocks you expect to log.
8 ** If the current transaction is too
9 ** old, it will block until the current transaction is
10 ** finished, and then start a new one.
11 ** Usually, your transaction will get joined in with
12 ** previous ones for speed.
13 **
14 ** journal_join -- same as journal_begin, but won't block on the current
15 ** transaction regardless of age. Don't ever call
16 ** this. Ever. There are only two places it should be
17 ** called from, and they are both inside this file.
18 **
19 ** journal_mark_dirty -- adds blocks into this transaction. clears any flags
20 ** that might make them get sent to disk
21 ** and then marks them BH_JDirty. Puts the buffer head
22 ** into the current transaction hash.
23 **
24 ** journal_end -- if the current transaction is batchable, it does nothing
25 ** otherwise, it could do an async/synchronous commit, or
26 ** a full flush of all log and real blocks in the
27 ** transaction.
28 **
29 ** flush_old_commits -- if the current transaction is too old, it is ended and
30 ** commit blocks are sent to disk. Forces commit blocks
31 ** to disk for all backgrounded commits that have been
32 ** around too long.
33 ** -- Note, if you call this as an immediate flush from
34 ** from within kupdate, it will ignore the immediate flag
35 */
37 #include <linux/time.h>
38 #include <linux/semaphore.h>
39 #include <linux/vmalloc.h>
40 #include <linux/reiserfs_fs.h>
41 #include <linux/kernel.h>
42 #include <linux/errno.h>
43 #include <linux/fcntl.h>
44 #include <linux/stat.h>
45 #include <linux/string.h>
46 #include <linux/smp_lock.h>
47 #include <linux/buffer_head.h>
48 #include <linux/workqueue.h>
49 #include <linux/writeback.h>
50 #include <linux/blkdev.h>
51 #include <linux/backing-dev.h>
52 #include <linux/uaccess.h>
53 #include <linux/slab.h>
55 #include <asm/system.h>
57 /* gets a struct reiserfs_journal_list * from a list head */
58 #define JOURNAL_LIST_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
59 j_list))
60 #define JOURNAL_WORK_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
61 j_working_list))
63 /* the number of mounted filesystems. This is used to decide when to
64 ** start and kill the commit workqueue
65 */
71 structs at 4k */
74 /* cnode stat bits. Move these into reiserfs_fs.h */
77 #define BLOCK_FREED_HOLDER 3 /* this block was freed during this transaction, and can't be written */
80 #define BLOCK_DIRTIED 5
82 /* journal list state bits */
83 #define LIST_TOUCHED 1
84 #define LIST_DIRTY 2
87 /* flags for do_journal_end */
109 /* values for join in do_journal_begin_r */
114 };
121 {
125 }
127 /*
128 ** clears BH_Dirty and sticks the buffer on the clean list. Called because I can't allow refile_buffer to
129 ** make schedule happen after I've freed a block. Look at remove_from_transaction and journal_mark_freed for
130 ** more details.
131 */
133 {
137 }
139 }
142 {
146 }
150 {
157 }
162 }
166 }
169 {
175 repeat:
183 }
188 }
190 }
193 {
202 }
203 }
206 {
217 }
218 }
219 }
222 b_blocknr_t block,
224 {
230 }
233 }
237 {
246 }
247 }
248 }
250 /*
251 ** only call this on FS unmount.
252 */
255 {
264 }
266 }
269 {
281 }
284 }
286 /*
287 ** get memory for JOURNAL_NUM_BITMAPS worth of bitmaps.
288 ** jb_array is the array to be filled in.
289 */
293 {
308 }
310 }
314 }
316 }
318 /*
319 ** find an available list bitmap. If you can't find one, flush a commit list
320 ** and try again
321 */
323 struct reiserfs_journal_list
325 {
340 }
343 }
344 }
347 }
350 }
352 /*
353 ** allocates a new chunk of X nodes, and links them all together as a list.
354 ** Uses the cnode->next and cnode->prev pointers
355 ** returns NULL on failure
356 */
358 {
363 }
367 }
374 }
377 }
379 /*
380 ** pulls a cnode off the free list, or returns NULL on failure
381 */
383 {
391 }
397 }
400 }
404 }
406 /*
407 ** returns a cnode to the free list
408 */
411 {
418 /* memset(cn, 0, sizeof(struct reiserfs_journal_cnode)) ; */
422 }
423 cn->prev = NULL; /* not needed with the memset, but I might kill the memset, and forget to do this */
425 }
428 {
431 }
433 /* return a cnode with same dev, block number and size in table, or null if not found */
435 super_block
437 struct
438 reiserfs_journal_cnode
441 {
448 }
450 }
452 /*
453 ** this actually means 'can this block be reallocated yet?'. If you set search_all, a block can only be allocated
454 ** if it is not in the current transaction, was not freed by the current transaction, and has no chance of ever
455 ** being overwritten by a replay after crashing.
456 **
457 ** If you don't set search_all, a block can only be allocated if it is not in the current transaction. Since deleting
458 ** a block removes it from the current transaction, this case should never happen. If you don't set search_all, make
459 ** sure you never write the block without logging it.
460 **
461 ** next_zero_bit is a suggestion about the next block to try for find_forward.
462 ** when bl is rejected because it is set in a journal list bitmap, we search
463 ** for the next zero bit in the bitmap that rejected bl. Then, we return that
464 ** through next_zero_bit for find_forward to try.
465 **
466 ** Just because we return something in next_zero_bit does not mean we won't
467 ** reject it on the next call to reiserfs_in_journal
468 **
469 */
473 {
483 /* If we aren't doing a search_all, this is a metablock, and it will be logged before use.
484 ** if we crash before the transaction that freed it commits, this transaction won't
485 ** have committed either, and the block will never be written
486 */
494 data)) {
498 data),
502 }
503 }
504 }
507 /* is it in any old transactions? */
512 }
514 /* is it in the current transaction. This should never happen */
518 }
521 /* safe for reuse */
523 }
525 /* insert cn into table
526 */
529 {
537 }
539 }
541 /* lock the current transaction */
543 {
547 }
549 /* unlock the current transaction */
551 {
553 }
556 {
558 }
562 {
566 }
569 }
571 /*
572 ** this used to be much more involved, and I'm keeping it just in case things get ugly again.
573 ** it gets called by flush_commit_list, and cleans up any data stored about blocks freed during a
574 ** transaction.
575 */
578 {
583 }
586 }
590 {
599 }
600 }
602 }
604 /*
605 * If page->mapping was null, we failed to truncate this page for
606 * some reason. Most likely because it was truncated after being
607 * logged via data=journal.
608 *
609 * This does a check to see if the buffer belongs to one of these
610 * lost pages before doing the final put_bh. If page->mapping was
611 * null, it tries to free buffers on the page, which should make the
612 * final page_cache_release drop the page from the lru.
613 */
615 {
626 }
627 }
630 {
637 }
640 else
645 }
648 {
651 else
655 }
658 {
668 }
671 {
678 }
681 {
688 }
692 {
701 }
702 }
704 #define CHUNK_SIZE 32
708 };
711 {
716 }
719 }
722 {
727 }
730 }
734 {
745 }
747 }
751 {
758 }
760 }
761 }
763 /*
764 * we want to free the jh when the buffer has been written
765 * and waited on
766 */
768 {
781 }
782 }
786 {
794 }
798 no_jh:
802 /* buffer must be locked for __add_jh, should be able to have
803 * two adds at the same time
804 */
808 }
814 }
817 }
820 {
822 }
824 {
826 }
828 #define JH_ENTRY(l) list_entry((l), struct reiserfs_jh, list)
833 {
851 }
859 }
860 /* in theory, dirty non-uptodate buffers should never get here,
861 * but the upper layer io error paths still have a few quirks.
862 * Handle them here as gracefully as we can
863 */
867 }
874 }
875 loop_next:
878 }
883 }
894 }
897 }
898 /* ugly interaction with invalidatepage here.
899 * reiserfs_invalidate_page will pin any buffer that has a valid
900 * journal head from an older transaction. If someone else sets
901 * our buffer dirty after we write it in the first loop, and
902 * then someone truncates the page away, nobody will ever write
903 * the buffer. We're safe if we write the page one last time
904 * after freeing the journal header.
905 */
910 }
913 }
916 }
920 {
929 find_first:
930 /*
931 * first we walk backwards to find the oldest uncommitted transation
932 */
943 }
945 /* if we didn't find any older uncommitted transactions, return now */
948 }
961 /* list we were called with is gone, return */
965 /* the one we just flushed is gone, this means all
966 * older lists are also gone, so first_jl is no longer
967 * valid either. Go back to the beginning.
968 */
972 }
973 }
979 }
980 }
982 }
985 {
992 }
995 }
997 /*
998 ** if this journal list still has commit blocks unflushed, send them to disk.
999 **
1000 ** log areas must be flushed in order (transaction 2 can't commit before transaction 1)
1001 ** Before the commit block can by written, every other log block must be safely on disk
1002 **
1003 */
1006 {
1008 b_blocknr_t bn;
1020 }
1024 /* before we can put our commit blocks on disk, we have to make sure everyone older than
1025 ** us is on disk too
1026 */
1033 /* list disappeared during flush_older_commits. return */
1035 }
1036 }
1038 /* make sure nobody is trying to flush this one at the same time */
1044 }
1047 /* this commit is done, exit */
1051 }
1054 }
1059 /*
1060 * We might sleep in numerous places inside
1061 * write_ordered_buffers. Relax the write lock.
1062 */
1069 }
1071 /*
1072 * for the description block and all the log blocks, submit any buffers
1073 * that haven't already reached the disk. Try to write at least 256
1074 * log blocks. later on, we will only wait on blocks that correspond
1075 * to this transaction, but while we're unplugging we might as well
1076 * get a chunk of data on there.
1077 */
1091 }
1093 }
1094 }
1097 /* We're skipping the commit if there's an error */
1101 /* wait on everything written so far before writing the commit
1102 * if we are in barrier mode, send the commit down now
1103 */
1113 }
1114 }
1123 // since we're using ll_rw_blk above, it might have skipped over
1124 // a locked buffer. Double check here
1125 //
1126 /* redundant, sync_dirty_buffer() checks */
1131 }
1133 #ifdef CONFIG_REISERFS_CHECK
1136 #endif
1138 }
1142 }
1147 /* If there was a write error in the journal - we can't commit
1148 * this transaction - it will be invalid and, if successful,
1149 * will just end up propagating the write error out to
1150 * the file system. */
1158 }
1163 }
1167 /* If there was a write error in the journal - we can't commit this
1168 * transaction - it will be invalid and, if successful, will just end
1169 * up propagating the write error out to the filesystem. */
1171 #ifdef CONFIG_REISERFS_CHECK
1173 #endif
1175 }
1181 }
1184 /* now, every commit block is on the disk. It is safe to allow blocks freed during this transaction to be reallocated */
1189 /* mark the metadata dirty */
1196 }
1198 put_jl:
1203 __func__);
1206 }
1208 /*
1209 ** flush_journal_list frequently needs to find a newer transaction for a given block. This does that, or
1210 ** returns NULL if it can't find anything
1211 */
1213 reiserfs_journal_cnode
1215 {
1223 }
1225 }
1227 }
1230 {
1240 }
1242 }
1249 /*
1250 ** once all the real blocks have been flushed, it is safe to remove them from the
1251 ** journal list for this transaction. Aside from freeing the cnode, this also allows the
1252 ** block to be reallocated for data blocks if it had been deleted.
1253 */
1257 {
1262 /* which is better, to lock once around the whole loop, or
1263 ** to lock for each call to remove_journal_hash?
1264 */
1272 }
1276 }
1280 }
1282 }
1284 /*
1285 ** if this timestamp is greater than the timestamp we wrote last to the header block, write it to the header block.
1286 ** once this is done, I can safely say the log area for this transaction won't ever be replayed, and I can start
1287 ** releasing blocks in this transaction for reuse as data blocks.
1288 ** called by flush_journal_list, before it calls remove_all_from_journal_list
1289 **
1290 */
1294 {
1307 #ifdef CONFIG_REISERFS_CHECK
1310 #endif
1312 }
1313 }
1317 b_data);
1330 }
1336 sync:
1341 }
1346 }
1347 }
1349 }
1354 {
1356 }
1358 /*
1359 ** flush any and all journal lists older than you are
1360 ** can only be called from flush_journal_list
1361 */
1364 {
1370 /* we know we are the only ones flushing things, no extra race
1371 * protection is required.
1372 */
1373 restart:
1375 /* Did we wrap? */
1381 /* do not flush all */
1384 /* other_jl is now deleted from the list */
1386 }
1388 }
1392 {
1397 }
1398 }
1400 /* flush a journal list, both commit and real blocks
1401 **
1402 ** always set flushall to 1, unless you are calling from inside
1403 ** flush_journal_list
1404 **
1405 ** IMPORTANT. This can only be called while there are no journal writers,
1406 ** and the journal is locked. That means it can only be called from
1407 ** do_journal_end, or by journal_release
1408 */
1411 {
1427 }
1430 /* if flushall == 0, the lock is already held */
1435 }
1442 }
1446 /* if all the work is already done, get out of here */
1450 }
1452 /* start by putting the commit list on disk. This will also flush
1453 ** the commit lists of any olders transactions
1454 */
1461 /* are we done now? */
1465 }
1467 /* loop through each cnode, see if we need to write it,
1468 ** or wait on a more recent transaction, or just ignore it
1469 */
1473 }
1479 /* blocknr of 0 is no longer in the hash, ignore it */
1482 }
1484 /* This transaction failed commit. Don't write out to the disk */
1489 /* the order is important here. We check pjl to make sure we
1490 ** don't clear BH_JDirty_wait if we aren't the one writing this
1491 ** block to disk
1492 */
1496 /* we do this to make sure nobody releases the buffer while
1497 ** we are working with it
1498 */
1506 /* everything with !pjl && jwait should be writable */
1508 }
1509 }
1511 /* if someone has this block in a newer transaction, just make
1512 ** sure they are committed, and don't try writing it to disk
1513 */
1518 }
1520 /* bh == NULL when the block got to disk on its own, OR,
1521 ** the block got freed in a future transaction
1522 */
1525 }
1527 /* this should never happen. kupdate_one_transaction has this list
1528 ** locked while it works, so we should never see a buffer here that
1529 ** is not marked JDirty_wait
1530 */
1533 "BAD! buffer %llu %cdirty %cjwait, "
1538 }
1540 /* we inc again because saved_bh gets decremented at free_cnode */
1547 else
1549 count++;
1555 }
1556 free_cnode:
1560 /* we incremented this to keep others from taking the buffer head away */
1565 }
1566 }
1567 }
1575 }
1584 }
1586 #ifdef CONFIG_REISERFS_CHECK
1589 #endif
1591 }
1592 /* note, we must clear the JDirty_wait bit after the up to date
1593 ** check, otherwise we race against our flushpage routine
1594 */
1598 /* drop one ref for us */
1600 /* drop one ref for journal_mark_dirty */
1602 }
1604 }
1605 }
1610 __func__);
1611 flush_older_and_return:
1613 /* before we can update the journal header block, we _must_ flush all
1614 ** real blocks from all older transactions to disk. This is because
1615 ** once the header block is updated, this transaction will not be
1616 ** replayed after a crash
1617 */
1620 }
1623 /* before we can remove everything from the hash tables for this
1624 ** transaction, we must make sure it can never be replayed
1625 **
1626 ** since we are only called from do_journal_end, we know for sure there
1627 ** are no allocations going on while we are flushing journal lists. So,
1628 ** we only need to update the journal header block for the last list
1629 ** being flushed
1630 */
1632 err =
1640 __func__);
1641 }
1651 }
1654 /* not strictly required since we are freeing the list, but it should
1655 * help find code using dead lists later on
1656 */
1669 }
1673 {
1681 /* if the blocknr == 0, this has been cleared from the hash,
1682 ** skip it
1683 */
1686 }
1689 next:
1692 }
1694 }
1699 {
1707 }
1711 /* if the blocknr == 0, this has been cleared from the hash,
1712 ** skip it
1713 */
1716 }
1719 /* we can race against journal_mark_freed when we try
1720 * to lock_buffer(cn->bh), so we have to inc the buffer
1721 * count, and recheck things after locking
1722 */
1731 ret++;
1733 /* note, cn->bh might be null now */
1735 }
1737 }
1738 next:
1741 }
1743 }
1745 /* used by flush_commit_list */
1748 {
1756 /* look for a more recent transaction that logged this
1757 ** buffer. Only the most recent transaction with a buffer in
1758 ** it is allowed to send that buffer to disk
1759 */
1764 /* if the buffer is prepared, it will either be logged
1765 * or restored. If restored, we need to make sure
1766 * it actually gets marked dirty
1767 */
1774 }
1775 }
1777 }
1779 }
1786 {
1799 }
1801 /* we've got j_flush_mutex held, nobody is going to delete any
1802 * of these lists out from underneath us
1803 */
1812 }
1817 transactions_flushed++;
1821 /* did we wrap? */
1824 }
1827 /* don't bother with older transactions */
1830 }
1833 }
1835 done:
1838 }
1840 /* for o_sync and fsync heavy applications, they tend to use
1841 ** all the journa list slots with tiny transactions. These
1842 ** trigger lots and lots of calls to update the header block, which
1843 ** adds seeks and slows things down.
1844 **
1845 ** This function tries to clear out a large chunk of the journal lists
1846 ** at once, which makes everything faster since only the newest journal
1847 ** list updates the header block
1848 */
1851 {
1864 /* in data logging mode, try harder to flush a lot of blocks */
1867 /* flush for 256 transactions or limit blocks, whichever comes first */
1872 }
1876 }
1882 }
1883 /* try to find a group of blocks we can flush across all the
1884 ** transactions, but only bother if we've actually spanned
1885 ** across multiple lists
1886 */
1889 }
1892 }
1894 /*
1895 ** removes any nodes in table with name block and dev as bh.
1896 ** only touchs the hnext and hprev pointers.
1897 */
1902 {
1909 }
1917 }
1922 }
1930 }
1932 }
1933 }
1936 {
1946 }
1947 /* j_header_bh is on the journal dev, make sure not to release the journal
1948 * dev until we brelse j_header_bh
1949 */
1952 }
1954 /*
1955 ** call on unmount. Only set error to 1 if you haven't made your way out
1956 ** of read_super() yet. Any other caller must keep error at 0.
1957 */
1960 {
1965 /* we only want to flush out transactions if we were called with error == 0
1966 */
1968 /* end the current trans */
1972 /* make sure something gets logged to force our way into the flush code */
1981 }
1982 }
1984 /* this also catches errors during the do_journal_end above */
1994 }
1995 }
1997 reiserfs_mounted_fs_count--;
1998 /* wait for all commits to finish */
2001 /*
2002 * We must release the write lock here because
2003 * the workqueue job (flush_async_commit) needs this lock
2004 */
2011 }
2018 }
2020 /*
2021 ** call on unmount. flush all journal trans, release all alloc'd ram
2022 */
2025 {
2027 }
2029 /*
2030 ** only call from an error condition inside reiserfs_read_super!
2031 */
2034 {
2036 }
2038 /* compares description block with commit block. returns 1 if they differ, 0 if they are the same */
2042 {
2048 }
2050 }
2052 /* returns 0 if it did not find a description block
2053 ** returns -1 if it found a corrupt commit block
2054 ** returns 1 if both desc and commit were valid
2055 */
2060 {
2075 "journal-986: transaction "
2076 "is valid returning because trans_id %d is greater than "
2081 }
2085 "journal-1087: transaction "
2086 "is valid returning because mount_id %d is less than "
2091 }
2094 "Bad transaction length %d "
2098 }
2101 /* ok, we have a journal description block, lets see if the transaction was valid */
2102 c_bh =
2112 "journal_transaction_is_valid, commit offset %ld had bad "
2123 "journal-1004: "
2124 "transaction_is_valid setting oldest invalid trans_id "
2127 }
2129 }
2132 "journal-1006: found valid "
2141 }
2142 }
2145 {
2149 }
2150 }
2152 /*
2153 ** given the start, and values for the oldest acceptable transactions,
2154 ** this either reads in a replays a transaction, or returns because the transaction
2155 ** is invalid, or too old.
2156 */
2162 {
2187 cur_dblock -
2191 }
2194 "journal_read_trans skipping because %d is != "
2196 newest_mount_id);
2199 }
2206 }
2210 "journal_read_transaction, "
2219 }
2227 }
2230 /* now we know we've got a good transaction, and it was inside the valid time ranges */
2243 }
2244 /* get all the buffer heads */
2261 }
2264 "REPLAY FAILURE fsck required! "
2265 "Block to replay is outside of "
2268 }
2269 /* make sure we don't try to replay onto log or reserved area */
2273 "REPLAY FAILURE fsck required! "
2275 abort_replay:
2283 }
2284 }
2285 /* read in the log blocks, memcpy to the corresponding real block */
2295 "REPLAY FAILURE fsck required! "
2305 }
2310 }
2311 /* flush out the real blocks */
2315 }
2320 "REPLAY FAILURE, fsck required! "
2329 }
2331 }
2332 cur_dblock =
2340 /* init starting values for the first transaction, in case this is the last transaction to be replayed. */
2344 /* check for trans_id overflow */
2352 }
2354 /* This function reads blocks starting from block and to max_block of bufsize
2355 size (but no more than BUFNR blocks at a time). This proved to improve
2356 mounting speed on self-rebuilding raid5 arrays at least.
2357 Right now it is only used from journal code. But later we might use it
2358 from other places.
2359 Note: Do not use journal_getblk/sb_getblk functions here! */
2362 b_blocknr_t max_block)
2363 {
2375 }
2385 }
2395 }
2397 /*
2398 ** read and replay the log
2399 ** on a clean unmount, the journal header's next unflushed pointer will be to an invalid
2400 ** transaction. This tests that before finding all the transactions in the log, which makes normal mount times fast.
2401 **
2402 ** After a crash, this starts with the next unflushed transaction, and replays until it finds one too old, or invalid.
2403 **
2404 ** On exit, it sets things up so the first transaction will work correctly.
2405 */
2407 {
2429 /* step 1, read in the journal header block. Check the transaction it says
2430 ** is the first unflushed, and if that transaction is not valid,
2431 ** replay is done
2432 */
2438 }
2443 oldest_start =
2449 "journal-1153: found in "
2450 "header: first_unflushed_offset %d, last_flushed_trans_id "
2455 /* now, we try to read the first unflushed offset. If it is not valid,
2456 ** there is nothing more we can do, and it makes no sense to read
2457 ** through the whole log.
2458 */
2459 d_bh =
2466 }
2469 }
2471 /* ok, there are transactions that need to be replayed. start with the first log block, find
2472 ** all the valid transactions, and pick out the oldest.
2473 */
2478 /* Note that it is required for blocksize of primary fs device and journal
2479 device to be the same */
2480 d_bh =
2485 ret =
2496 "journal-1179: Setting "
2498 oldest_start -
2499 SB_ONDISK_JOURNAL_1st_BLOCK
2502 /* one we just read was older */
2506 "journal-1180: Resetting "
2508 oldest_start -
2509 SB_ONDISK_JOURNAL_1st_BLOCK
2511 }
2515 "journal-1299: Setting "
2518 }
2521 cur_dblock++;
2522 }
2524 }
2526 start_log_replay:
2530 "journal-1206: Starting replay "
2533 oldest_trans_id);
2535 }
2538 ret =
2545 }
2546 cur_dblock =
2548 replay_count++;
2551 }
2556 }
2557 /* j_start does not get set correctly if we don't replay any transactions.
2558 ** if we had a valid journal_header, set j_start to the first unflushed transaction value,
2559 ** copy the trans_id from the header
2560 */
2565 /* check for trans_id overflow */
2573 }
2581 }
2585 /* replay failed, caller must call free_journal_ram and abort
2586 ** the mount
2587 */
2589 }
2591 }
2594 {
2606 }
2609 {
2611 }
2615 {
2625 }
2630 }
2632 }
2637 {
2639 dev_t jdev;
2652 /* there is no "jdev" option and journal is on separate device */
2668 }
2671 }
2674 }
2686 }
2693 }
2695 /**
2696 * When creating/tuning a file system user can assign some
2697 * journal params within boundaries which depend on the ratio
2698 * blocksize/standard_blocksize.
2699 *
2700 * For blocks >= standard_blocksize transaction size should
2701 * be not less then JOURNAL_TRANS_MIN_DEFAULT, and not more
2702 * then JOURNAL_TRANS_MAX_DEFAULT.
2703 *
2704 * For blocks < standard_blocksize these boundaries should be
2705 * decreased proportionally.
2706 */
2707 #define REISERFS_STANDARD_BLKSIZE (4096)
2711 {
2713 /* Non-default journal params.
2714 Do sanity check for them. */
2722 JOURNAL_MIN_RATIO) {
2724 "bad transaction max size (%u). "
2727 }
2731 "bad transaction max batch (%u). "
2734 }
2736 /* Default journal params.
2737 The file system was created by old version
2738 of mkreiserfs, so some fields contain zeros,
2739 and we need to advise proper values for them */
2744 }
2748 }
2750 }
2752 /*
2753 ** must be called once on fs mount. calls journal_read for you
2754 */
2757 {
2767 /*
2768 * Unlock here to avoid various RECLAIM-FS-ON <-> IN-RECLAIM-FS
2769 * dependency inversion warnings.
2770 */
2778 }
2793 /* reserved for journal area support */
2795 REISERFS_OLD_DISK_OFFSET_IN_BYTES
2799 REISERFS_DISK_OFFSET_IN_BYTES /
2802 /* Sanity check to see is the standard journal fitting withing first bitmap
2803 (actual for small blocksizes) */
2808 "journal does not fit for area addressed "
2809 "by first of bitmap blocks. It starts at "
2815 }
2817 /*
2818 * We need to unlock here to avoid creating the following
2819 * dependency:
2820 * reiserfs_lock -> sysfs_mutex
2821 * Because the reiserfs mmap path creates the following dependency:
2822 * mm->mmap -> reiserfs_lock, hence we have
2823 * mm->mmap -> reiserfs_lock ->sysfs_mutex
2824 * This would ends up in a circular dependency with sysfs readdir path
2825 * which does sysfs_mutex -> mm->mmap_sem
2826 * This is fine because the reiserfs lock is useless in mount path,
2827 * at least until we call journal_begin. We keep it for paranoid
2828 * reasons.
2829 */
2836 }
2841 /* read journal header */
2849 }
2852 /* make sure that journal matches to the super block */
2857 "journal header magic %x (device %s) does "
2864 }
2879 }
2882 "journal first block %u, max trans len %u, max batch %u, "
2929 "allocation failed (%ld bytes). Journal is "
2930 "too large for available memory. Usually "
2934 }
2943 }
2948 }
2950 reiserfs_mounted_fs_count++;
2955 }
2960 free_and_return:
2963 }
2965 /*
2966 ** test for a polite end of the current transaction. Used by file_write, and should
2967 ** be used by delete to make sure they don't write more than can fit inside a single
2968 ** transaction
2969 */
2972 {
2975 /* cannot restart while nested */
2985 }
2986 /* protected by the BKL here */
2990 }
2992 /* this must be called inside a transaction, and requires the
2993 ** kernel_lock to be held
2994 */
2996 {
3002 }
3004 /* this must be called without a transaction started, and does not
3005 ** require BKL
3006 */
3008 {
3012 }
3014 /* this must be called without a transaction started, and does not
3015 ** require BKL
3016 */
3018 {
3022 }
3025 {
3026 wait_queue_t wait;
3030 /*
3031 * we don't want to use wait_event here because
3032 * we only want to wait once.
3033 */
3041 }
3044 }
3047 {
3051 }
3054 {
3066 }
3072 }
3073 }
3075 /* join == true if you must join an existing transaction.
3076 ** join == false if you can deal with waiting for others to finish
3077 **
3078 ** this will block until the transaction is joinable. send the number of blocks you
3079 ** expect to use in nblocks.
3080 */
3084 {
3096 /* set here for journal_join */
3100 relock:
3106 }
3116 }
3119 /* if there is no room in the journal OR
3120 ** if this transaction is too old, and we weren't called joinable, wait for it to finish before beginning
3121 ** we don't sleep if there aren't other writers
3122 */
3125 (!join
3142 sched_count++;
3145 }
3146 }
3147 /* don't mess with joining the transaction if all we have to do is
3148 * wait for someone else to do a commit
3149 */
3154 }
3156 }
3161 /* someone might have ended the transaction while we joined */
3166 }
3173 }
3174 /* we are the first writer, set trans_id */
3177 }
3188 out_fail:
3190 /* Re-set th->t_super, so we can properly keep track of how many
3191 * persistent transactions there are. We need to do this so if this
3192 * call is part of a failed restart_transaction, we can free it later */
3195 }
3198 super_block
3201 {
3205 /* if we're nesting into an existing transaction. It will be
3206 ** persistent on its own
3207 */
3214 }
3222 }
3226 }
3229 {
3234 else
3239 }
3241 }
3245 {
3248 /* this keeps do_journal_end from NULLing out the current->journal_info
3249 ** pointer
3250 */
3254 }
3258 {
3261 /* this keeps do_journal_end from NULLing out the current->journal_info
3262 ** pointer
3263 */
3267 }
3271 {
3277 /* we are nesting into the current transaction */
3284 "BAD: refcount <= 1, but "
3288 /* we've ended up with a handle from a different filesystem.
3289 ** save it and restore on journal_end. This should never
3290 ** really happen...
3291 */
3296 }
3299 }
3303 /* I guess this boils down to being the reciprocal of clm-2100 above.
3304 * If do_journal_begin_r fails, we need to put it back, since journal_end
3305 * won't be called to do it. */
3308 else
3312 }
3314 /*
3315 ** puts bh into the current transaction. If it was already there, reorders removes the
3316 ** old pointers from the hash, and puts new ones in (to make sure replay happen in the right order).
3317 **
3318 ** if it was dirty, cleans and files onto the clean list. I can't let it be dirty again until the
3319 ** transaction is committed.
3320 **
3321 ** if j_len, is bigger than j_len_alloc, it pushes j_len_alloc to 10 + j_len.
3322 */
3325 {
3337 }
3343 /* already in this transaction, we are done */
3347 }
3349 /* this must be turned into a panic instead of a warning. We can't allow
3350 ** a dirty or journal_dirty or locked buffer to be logged, as some changes
3351 ** could get to disk too early. NOT GOOD.
3352 */
3355 "buffer %llu bad state "
3362 }
3369 }
3370 /* this error means I've screwed up, and we've overflowed the transaction.
3371 ** Nothing can be done here, except make the FS readonly or panic.
3372 */
3377 }
3383 }
3387 }
3391 /* now put this guy on the end */
3396 }
3401 }
3412 }
3413 }
3423 }
3425 }
3429 {
3437 }
3444 /* we aren't allowed to close a nested transaction on a different
3445 ** filesystem from the one in the task struct
3446 */
3452 }
3456 }
3457 }
3459 /* removes from the current transaction, relsing and descrementing any counters.
3460 ** also files the removed buffer directly onto the clean list
3461 **
3462 ** called by journal_mark_freed when a block has been deleted
3463 **
3464 ** returns 1 if it cleaned and relsed the buffer. 0 otherwise
3465 */
3468 {
3477 }
3481 }
3484 }
3487 }
3490 }
3504 }
3506 }
3511 }
3513 /*
3514 ** for any cnode in a journal list, it can only be dirtied of all the
3515 ** transactions that include it are committed to disk.
3516 ** this checks through each transaction, and returns 1 if you are allowed to dirty,
3517 ** and 0 if you aren't
3518 **
3519 ** it is called by dirty_journal_list, which is called after flush_commit_list has gotten all the log
3520 ** blocks for a given transaction on disk
3521 **
3522 */
3524 {
3530 /* first test hprev. These are all newer than cn, so any node here
3531 ** with the same block number and dev means this node can't be sent
3532 ** to disk right now.
3533 */
3538 }
3540 }
3541 /* then test hnext. These are all older than cn. As long as they
3542 ** are committed to the log, it is safe to write cn to disk
3543 */
3550 }
3552 }
3554 }
3556 /* syncs the commit blocks, but does not force the real buffers to disk
3557 ** will wait until the current transaction is done/committed before returning
3558 */
3561 {
3565 /* you can sync while nested, very, very bad */
3571 }
3573 }
3575 /*
3576 ** writeback the pending async commits to disk
3577 */
3579 {
3588 /* last entry is the youngest, commit it and you get everything */
3592 }
3594 }
3596 /*
3597 ** flushes any old transactions to disk
3598 ** ends the current transaction if it is too old
3599 */
3601 {
3607 /* safety check so we don't flush while we are replaying the log during
3608 * mount
3609 */
3612 }
3614 /* check the current transaction. If there are no writers, and it is
3615 * too old, finish it, and force the commit blocks to disk
3616 */
3628 /* we're only being called from kreiserfsd, it makes no sense to do
3629 ** an async commit so that kreiserfsd can do it later
3630 */
3632 }
3633 }
3635 }
3637 /*
3638 ** returns 0 if do_journal_end should return right away, returns 1 if do_journal_end should finish the commit
3639 **
3640 ** if the current transaction is too old, but still has writers, this will wait on j_join_wait until all
3641 ** the writers are done. By the time it wakes up, the transaction it was called has already ended, so it just
3642 ** flushes the commit list and returns 0.
3643 **
3644 ** Won't batch when flush or commit_now is set. Also won't batch when others are waiting on j_join_wait.
3645 **
3646 ** Note, we can't allow the journal_end to proceed while there are still writers in the log.
3647 */
3651 {
3666 }
3669 if (atomic_read(&(journal->j_wcount)) > 0) { /* <= 0 is allowed. unmounting might not call begin */
3671 }
3673 /* BUG, deal with case where j_len is 0, but people previously freed blocks need to be released
3674 ** will be dealt with by next transaction that actually writes something, but should be taken
3675 ** care of in this trans
3676 */
3679 /* if wcount > 0, and we are called to with flush or commit_now,
3680 ** we wait on j_join_wait. We will wake up when the last writer has
3681 ** finished the transaction, and started it on its way to the disk.
3682 ** Then, we flush the commit or journal list, and just return 0
3683 ** because the rest of journal end was already done for this transaction.
3684 */
3696 }
3699 /* sleep while the current transaction is still j_jlocked */
3708 }
3710 }
3711 }
3718 }
3720 }
3723 }
3725 /* deal with old transactions where we are the last writers */
3730 }
3731 /* don't batch when someone is waiting on j_join_wait */
3732 /* don't batch when syncing the commit or flushing the whole trans */
3740 }
3746 }
3748 }
3750 /*
3751 ** Does all the work that makes deleting blocks safe.
3752 ** when deleting a block mark BH_JNew, just remove it from the current transaction, clean it's buffer_head and move on.
3753 **
3754 ** otherwise:
3755 ** set a bit for the block in the journal bitmap. That will prevent it from being allocated for unformatted nodes
3756 ** before this transaction has finished.
3757 **
3758 ** mark any cnodes for this block as BLOCK_FREED, and clear their bh pointers. That will prevent any old transactions with
3759 ** this block from trying to flush to the real location. Since we aren't removing the cnode from the journal_list_hash,
3760 ** the block can't be reallocated yet.
3761 **
3762 ** Then remove it from the current transaction, decrementing any counters and filing it on the clean list.
3763 */
3766 {
3778 }
3779 /* if it is journal new, we just remove it from this transaction */
3786 /* set the bit for this block in the journal bitmap for this transaction */
3791 }
3794 /* Note, the entire while loop is not allowed to schedule. */
3799 }
3802 /* find all older transactions with this block, make sure they don't try to write it out */
3804 blocknr);
3810 /* remove_from_transaction will brelse the buffer if it was
3811 ** in the current trans
3812 */
3814 bh);
3817 bh);
3825 }
3826 }
3830 j_nonzerolen));
3831 }
3833 }
3834 }
3836 }
3837 }
3842 }
3845 {
3849 }
3851 /*
3852 * returns -1 on error, 0 if no commits/barriers were done and 1
3853 * if a transaction was actually committed and the barrier was done
3854 */
3857 {
3863 /* is it from the current transaction, or from an unknown transaction? */
3866 /* try to let other writers come in and grow this transaction */
3870 }
3876 /* someone might have ended this transaction while we joined */
3883 }
3890 /* this gets tricky, we have to make sure the journal list in
3891 * the inode still exists. We know the list is still around
3892 * if we've got a larger transaction id than the oldest list
3893 */
3894 flush_commit_only:
3896 /*
3897 * we only set ret to 1 when we know for sure
3898 * the barrier hasn't been started yet on the commit
3899 * block.
3900 */
3906 }
3907 }
3908 /* otherwise the list is gone, and long since committed */
3910 }
3913 {
3917 /* for the whole inode, assume unset id means it was
3918 * changed in the current transaction. More conservative
3919 */
3923 /* jl will be updated in __commit_trans_jl */
3924 }
3927 }
3931 {
3936 }
3946 }
3947 }
3949 }
3952 /*
3953 ** before we can change a metadata block, we have to make sure it won't
3954 ** be written to disk while we are altering it. So, we must:
3955 ** clean it
3956 ** wait on it.
3957 **
3958 */
3961 {
3968 }
3973 }
3976 }
3979 {
3988 /* this check should always be run, to send old lists to disk */
3995 }
3996 }
3997 }
3999 /*
4000 ** long and ugly. If flush, will not return until all commit
4001 ** blocks and all real buffers in the trans are on disk.
4002 ** If no_async, won't return until all commit blocks are on disk.
4003 **
4004 ** keep reading, there are comments as you go along
4005 **
4006 ** If the journal is aborted, we just clean up. Things like flushing
4007 ** journal lists, etc just won't happen.
4008 */
4012 {
4034 /* protect flush_older_commits from doing mistakes if the
4035 transaction ID counter gets overflowed. */
4048 }
4054 }
4058 }
4060 /* check_journal_end locks the journal, and unlocks if it does not return 1
4061 ** it tells us if we should continue with the journal_end, or just return
4062 */
4068 }
4070 /* check_journal_end might set these, check again */
4073 }
4075 /*
4076 ** j must wait means we have to flush the log blocks, and the real blocks for
4077 ** this transaction
4078 */
4081 }
4082 #ifdef REISERFS_PREALLOCATE
4083 /* quota ops might need to nest, setup the journal_info pointer for them
4084 * and raise the refcount so that it is > 0. */
4088 * the transaction */
4091 #endif
4093 /* setup description block */
4094 d_bh =
4104 /* setup commit block. Don't write (keep it clean too) this one until after everyone else is written */
4113 /* init this journal list */
4116 /* we lock the commit before doing anything because
4117 * we want to make sure nobody tries to run flush_commit_list until
4118 * the new transaction is fully setup, and we've already flushed the
4119 * ordered bh list
4120 */
4123 /* save the transaction id in case we need to commit it later */
4136 /* The ENTIRE FOR LOOP MUST not cause schedule to occur.
4137 ** for each real block, add it to the journal list hash,
4138 ** copy into real block index array in the commit or desc block
4139 */
4147 }
4150 }
4155 }
4157 /* make sure the block we are trying to log is not a block
4158 of journal or reserved area */
4163 "Trying to log block %lu, "
4166 }
4179 }
4181 i--;
4182 }
4183 }
4189 /* special check in case all buffers in the journal were marked for not logging */
4192 /* we're about to dirty all the log blocks, mark the description block
4193 * dirty now too. Don't mark the commit block dirty until all the
4194 * others are on disk
4195 */
4198 /* first data block is j_start + 1, so add one to cur_write_start wherever you use it */
4204 /* copy all the real blocks into log area. dirty log blocks */
4209 tmp_bh =
4213 jindex) %
4223 jindex++;
4227 /* JDirty cleared sometime during transaction. don't log this one */
4229 "BAD, buffer in journal hash, "
4232 }
4239 }
4241 /* we are done with both the c_bh and d_bh, but
4242 ** c_bh must be written after all other commit blocks,
4243 ** so we dirty/relse c_bh in flush_commit_list, with commit_left <= 1.
4244 */
4248 /* now it is safe to insert this transaction on the main list */
4253 /* reset journal values for the next transaction */
4264 /* check for trans_id overflow */
4274 // make sure reiserfs_add_jh sees the new current_jl before we
4275 // write out the tails
4278 /* tail conversion targets have to hit the disk before we end the
4279 * transaction. Otherwise a later transaction might repack the tail
4280 * before this transaction commits, leaving the data block unflushed and
4281 * clean, if we crash before the later transaction commits, the data block
4282 * is lost.
4283 */
4289 }
4293 /* honor the flush wishes from the caller, simple commits can
4294 ** be done outside the journal lock, they are done below
4295 **
4296 ** if we don't flush the commit list right now, we put it into
4297 ** the work queue so the people waiting on the async progress work
4298 ** queue don't wait for this proc to flush journal lists and such.
4299 */
4306 /* if the next transaction has any chance of wrapping, flush
4307 ** transactions that might get overwritten. If any journal lists are very
4308 ** old flush them as well.
4309 */
4310 first_jl:
4321 /* if we don't cross into the next transaction and we don't
4322 * wrap, there is no way we can overlap any later transactions
4323 * break now
4324 */
4326 }
4336 /* we don't overlap anything from out start to the end of the
4337 * log, and our wrapped portion doesn't overlap anything at
4338 * the start of the log. We can break
4339 */
4341 }
4342 }
4343 }
4352 }
4356 /* wake up any body waiting to join. */
4363 }
4364 out:
4368 /* Re-set th->t_super, so we can properly keep track of how many
4369 * persistent transactions there are. We need to do this so if this
4370 * call is part of a failed restart_transaction, we can free it later */
4374 }
4376 /* Send the file system read only and refuse new transactions */
4378 {
4389 #ifdef CONFIG_REISERFS_CHECK
4391 #endif
4392 }