| blob | a059879667b1a7fdfd1399541ead50baf18e1af4 |
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>
54 #include <asm/system.h>
56 /* gets a struct reiserfs_journal_list * from a list head */
57 #define JOURNAL_LIST_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
58 j_list))
59 #define JOURNAL_WORK_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
60 j_working_list))
62 /* the number of mounted filesystems. This is used to decide when to
63 ** start and kill the commit workqueue
64 */
70 structs at 4k */
73 /* cnode stat bits. Move these into reiserfs_fs.h */
76 #define BLOCK_FREED_HOLDER 3 /* this block was freed during this transaction, and can't be written */
79 #define BLOCK_DIRTIED 5
81 /* journal list state bits */
82 #define LIST_TOUCHED 1
83 #define LIST_DIRTY 2
86 /* flags for do_journal_end */
108 /* values for join in do_journal_begin_r */
113 };
120 {
124 }
126 /*
127 ** clears BH_Dirty and sticks the buffer on the clean list. Called because I can't allow refile_buffer to
128 ** make schedule happen after I've freed a block. Look at remove_from_transaction and journal_mark_freed for
129 ** more details.
130 */
132 {
136 }
138 }
141 {
145 }
149 {
156 }
161 }
165 }
168 {
174 repeat:
182 }
187 }
189 }
192 {
201 }
202 }
205 {
216 }
217 }
218 }
221 b_blocknr_t block,
223 {
229 }
232 }
236 {
245 }
246 }
247 }
249 /*
250 ** only call this on FS unmount.
251 */
254 {
263 }
265 }
268 {
280 }
283 }
285 /*
286 ** get memory for JOURNAL_NUM_BITMAPS worth of bitmaps.
287 ** jb_array is the array to be filled in.
288 */
292 {
307 }
309 }
313 }
315 }
317 /*
318 ** find an available list bitmap. If you can't find one, flush a commit list
319 ** and try again
320 */
322 struct reiserfs_journal_list
324 {
339 }
342 }
343 }
346 }
349 }
351 /*
352 ** allocates a new chunk of X nodes, and links them all together as a list.
353 ** Uses the cnode->next and cnode->prev pointers
354 ** returns NULL on failure
355 */
357 {
362 }
366 }
373 }
376 }
378 /*
379 ** pulls a cnode off the free list, or returns NULL on failure
380 */
382 {
390 }
396 }
399 }
403 }
405 /*
406 ** returns a cnode to the free list
407 */
410 {
417 /* memset(cn, 0, sizeof(struct reiserfs_journal_cnode)) ; */
421 }
422 cn->prev = NULL; /* not needed with the memset, but I might kill the memset, and forget to do this */
424 }
427 {
430 }
432 /* return a cnode with same dev, block number and size in table, or null if not found */
434 super_block
436 struct
437 reiserfs_journal_cnode
440 {
447 }
449 }
451 /*
452 ** this actually means 'can this block be reallocated yet?'. If you set search_all, a block can only be allocated
453 ** if it is not in the current transaction, was not freed by the current transaction, and has no chance of ever
454 ** being overwritten by a replay after crashing.
455 **
456 ** If you don't set search_all, a block can only be allocated if it is not in the current transaction. Since deleting
457 ** a block removes it from the current transaction, this case should never happen. If you don't set search_all, make
458 ** sure you never write the block without logging it.
459 **
460 ** next_zero_bit is a suggestion about the next block to try for find_forward.
461 ** when bl is rejected because it is set in a journal list bitmap, we search
462 ** for the next zero bit in the bitmap that rejected bl. Then, we return that
463 ** through next_zero_bit for find_forward to try.
464 **
465 ** Just because we return something in next_zero_bit does not mean we won't
466 ** reject it on the next call to reiserfs_in_journal
467 **
468 */
472 {
482 /* If we aren't doing a search_all, this is a metablock, and it will be logged before use.
483 ** if we crash before the transaction that freed it commits, this transaction won't
484 ** have committed either, and the block will never be written
485 */
493 data)) {
497 data),
501 }
502 }
503 }
506 /* is it in any old transactions? */
511 }
513 /* is it in the current transaction. This should never happen */
517 }
520 /* safe for reuse */
522 }
524 /* insert cn into table
525 */
528 {
536 }
538 }
540 /* lock the current transaction */
542 {
546 }
548 /* unlock the current transaction */
550 {
552 }
555 {
557 }
561 {
565 }
568 }
570 /*
571 ** this used to be much more involved, and I'm keeping it just in case things get ugly again.
572 ** it gets called by flush_commit_list, and cleans up any data stored about blocks freed during a
573 ** transaction.
574 */
577 {
582 }
585 }
589 {
598 }
599 }
601 }
603 /*
604 * If page->mapping was null, we failed to truncate this page for
605 * some reason. Most likely because it was truncated after being
606 * logged via data=journal.
607 *
608 * This does a check to see if the buffer belongs to one of these
609 * lost pages before doing the final put_bh. If page->mapping was
610 * null, it tries to free buffers on the page, which should make the
611 * final page_cache_release drop the page from the lru.
612 */
614 {
625 }
626 }
629 {
636 }
639 else
644 }
647 {
650 else
654 }
657 {
667 }
670 {
677 }
680 {
687 }
691 {
700 }
701 }
703 #define CHUNK_SIZE 32
707 };
710 {
715 }
718 }
721 {
726 }
729 }
733 {
744 }
746 }
750 {
757 }
759 }
760 }
762 /*
763 * we want to free the jh when the buffer has been written
764 * and waited on
765 */
767 {
780 }
781 }
785 {
793 }
797 no_jh:
801 /* buffer must be locked for __add_jh, should be able to have
802 * two adds at the same time
803 */
807 }
813 }
816 }
819 {
821 }
823 {
825 }
827 #define JH_ENTRY(l) list_entry((l), struct reiserfs_jh, list)
832 {
850 }
858 }
859 /* in theory, dirty non-uptodate buffers should never get here,
860 * but the upper layer io error paths still have a few quirks.
861 * Handle them here as gracefully as we can
862 */
866 }
873 }
874 loop_next:
877 }
882 }
893 }
896 }
897 /* ugly interaction with invalidatepage here.
898 * reiserfs_invalidate_page will pin any buffer that has a valid
899 * journal head from an older transaction. If someone else sets
900 * our buffer dirty after we write it in the first loop, and
901 * then someone truncates the page away, nobody will ever write
902 * the buffer. We're safe if we write the page one last time
903 * after freeing the journal header.
904 */
909 }
912 }
915 }
919 {
928 find_first:
929 /*
930 * first we walk backwards to find the oldest uncommitted transation
931 */
942 }
944 /* if we didn't find any older uncommitted transactions, return now */
947 }
960 /* list we were called with is gone, return */
964 /* the one we just flushed is gone, this means all
965 * older lists are also gone, so first_jl is no longer
966 * valid either. Go back to the beginning.
967 */
971 }
972 }
978 }
979 }
981 }
984 {
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 }
2017 }
2019 /*
2020 ** call on unmount. flush all journal trans, release all alloc'd ram
2021 */
2024 {
2026 }
2028 /*
2029 ** only call from an error condition inside reiserfs_read_super!
2030 */
2033 {
2035 }
2037 /* compares description block with commit block. returns 1 if they differ, 0 if they are the same */
2041 {
2047 }
2049 }
2051 /* returns 0 if it did not find a description block
2052 ** returns -1 if it found a corrupt commit block
2053 ** returns 1 if both desc and commit were valid
2054 */
2059 {
2074 "journal-986: transaction "
2075 "is valid returning because trans_id %d is greater than "
2080 }
2084 "journal-1087: transaction "
2085 "is valid returning because mount_id %d is less than "
2090 }
2093 "Bad transaction length %d "
2097 }
2100 /* ok, we have a journal description block, lets see if the transaction was valid */
2101 c_bh =
2111 "journal_transaction_is_valid, commit offset %ld had bad "
2122 "journal-1004: "
2123 "transaction_is_valid setting oldest invalid trans_id "
2126 }
2128 }
2131 "journal-1006: found valid "
2140 }
2141 }
2144 {
2148 }
2149 }
2151 /*
2152 ** given the start, and values for the oldest acceptable transactions,
2153 ** this either reads in a replays a transaction, or returns because the transaction
2154 ** is invalid, or too old.
2155 */
2161 {
2186 cur_dblock -
2190 }
2193 "journal_read_trans skipping because %d is != "
2195 newest_mount_id);
2198 }
2205 }
2209 "journal_read_transaction, "
2218 }
2220 /* now we know we've got a good transaction, and it was inside the valid time ranges */
2233 }
2234 /* get all the buffer heads */
2251 }
2254 "REPLAY FAILURE fsck required! "
2255 "Block to replay is outside of "
2258 }
2259 /* make sure we don't try to replay onto log or reserved area */
2263 "REPLAY FAILURE fsck required! "
2265 abort_replay:
2273 }
2274 }
2275 /* read in the log blocks, memcpy to the corresponding real block */
2285 "REPLAY FAILURE fsck required! "
2295 }
2300 }
2301 /* flush out the real blocks */
2305 }
2310 "REPLAY FAILURE, fsck required! "
2319 }
2321 }
2322 cur_dblock =
2330 /* init starting values for the first transaction, in case this is the last transaction to be replayed. */
2334 /* check for trans_id overflow */
2342 }
2344 /* This function reads blocks starting from block and to max_block of bufsize
2345 size (but no more than BUFNR blocks at a time). This proved to improve
2346 mounting speed on self-rebuilding raid5 arrays at least.
2347 Right now it is only used from journal code. But later we might use it
2348 from other places.
2349 Note: Do not use journal_getblk/sb_getblk functions here! */
2352 b_blocknr_t max_block)
2353 {
2365 }
2375 }
2385 }
2387 /*
2388 ** read and replay the log
2389 ** on a clean unmount, the journal header's next unflushed pointer will be to an invalid
2390 ** transaction. This tests that before finding all the transactions in the log, which makes normal mount times fast.
2391 **
2392 ** After a crash, this starts with the next unflushed transaction, and replays until it finds one too old, or invalid.
2393 **
2394 ** On exit, it sets things up so the first transaction will work correctly.
2395 */
2397 {
2419 /* step 1, read in the journal header block. Check the transaction it says
2420 ** is the first unflushed, and if that transaction is not valid,
2421 ** replay is done
2422 */
2428 }
2433 oldest_start =
2439 "journal-1153: found in "
2440 "header: first_unflushed_offset %d, last_flushed_trans_id "
2445 /* now, we try to read the first unflushed offset. If it is not valid,
2446 ** there is nothing more we can do, and it makes no sense to read
2447 ** through the whole log.
2448 */
2449 d_bh =
2456 }
2459 }
2465 }
2467 /* ok, there are transactions that need to be replayed. start with the first log block, find
2468 ** all the valid transactions, and pick out the oldest.
2469 */
2474 /* Note that it is required for blocksize of primary fs device and journal
2475 device to be the same */
2476 d_bh =
2481 ret =
2492 "journal-1179: Setting "
2494 oldest_start -
2495 SB_ONDISK_JOURNAL_1st_BLOCK
2498 /* one we just read was older */
2502 "journal-1180: Resetting "
2504 oldest_start -
2505 SB_ONDISK_JOURNAL_1st_BLOCK
2507 }
2511 "journal-1299: Setting "
2514 }
2517 cur_dblock++;
2518 }
2520 }
2522 start_log_replay:
2526 "journal-1206: Starting replay "
2529 oldest_trans_id);
2531 }
2534 ret =
2541 }
2542 cur_dblock =
2544 replay_count++;
2547 }
2552 }
2553 /* j_start does not get set correctly if we don't replay any transactions.
2554 ** if we had a valid journal_header, set j_start to the first unflushed transaction value,
2555 ** copy the trans_id from the header
2556 */
2561 /* check for trans_id overflow */
2569 }
2577 }
2581 /* replay failed, caller must call free_journal_ram and abort
2582 ** the mount
2583 */
2585 }
2587 }
2590 {
2602 }
2605 {
2607 }
2611 {
2621 }
2626 }
2628 }
2633 {
2635 dev_t jdev;
2648 /* there is no "jdev" option and journal is on separate device */
2664 }
2667 }
2670 }
2682 }
2689 }
2691 /**
2692 * When creating/tuning a file system user can assign some
2693 * journal params within boundaries which depend on the ratio
2694 * blocksize/standard_blocksize.
2695 *
2696 * For blocks >= standard_blocksize transaction size should
2697 * be not less then JOURNAL_TRANS_MIN_DEFAULT, and not more
2698 * then JOURNAL_TRANS_MAX_DEFAULT.
2699 *
2700 * For blocks < standard_blocksize these boundaries should be
2701 * decreased proportionally.
2702 */
2703 #define REISERFS_STANDARD_BLKSIZE (4096)
2707 {
2709 /* Non-default journal params.
2710 Do sanity check for them. */
2718 JOURNAL_MIN_RATIO) {
2720 "bad transaction max size (%u). "
2723 }
2727 "bad transaction max batch (%u). "
2730 }
2732 /* Default journal params.
2733 The file system was created by old version
2734 of mkreiserfs, so some fields contain zeros,
2735 and we need to advise proper values for them */
2740 }
2744 }
2746 }
2748 /*
2749 ** must be called once on fs mount. calls journal_read for you
2750 */
2753 {
2763 /*
2764 * Unlock here to avoid various RECLAIM-FS-ON <-> IN-RECLAIM-FS
2765 * dependency inversion warnings.
2766 */
2774 }
2789 /* reserved for journal area support */
2791 REISERFS_OLD_DISK_OFFSET_IN_BYTES
2795 REISERFS_DISK_OFFSET_IN_BYTES /
2798 /* Sanity check to see is the standard journal fitting withing first bitmap
2799 (actual for small blocksizes) */
2804 "journal does not fit for area addressed "
2805 "by first of bitmap blocks. It starts at "
2811 }
2813 /*
2814 * We need to unlock here to avoid creating the following
2815 * dependency:
2816 * reiserfs_lock -> sysfs_mutex
2817 * Because the reiserfs mmap path creates the following dependency:
2818 * mm->mmap -> reiserfs_lock, hence we have
2819 * mm->mmap -> reiserfs_lock ->sysfs_mutex
2820 * This would ends up in a circular dependency with sysfs readdir path
2821 * which does sysfs_mutex -> mm->mmap_sem
2822 * This is fine because the reiserfs lock is useless in mount path,
2823 * at least until we call journal_begin. We keep it for paranoid
2824 * reasons.
2825 */
2832 }
2837 /* read journal header */
2845 }
2848 /* make sure that journal matches to the super block */
2853 "journal header magic %x (device %s) does "
2860 }
2875 }
2878 "journal first block %u, max trans len %u, max batch %u, "
2923 "allocation failed (%ld bytes). Journal is "
2924 "too large for available memory. Usually "
2928 }
2937 }
2942 }
2944 reiserfs_mounted_fs_count++;
2949 }
2954 free_and_return:
2957 }
2959 /*
2960 ** test for a polite end of the current transaction. Used by file_write, and should
2961 ** be used by delete to make sure they don't write more than can fit inside a single
2962 ** transaction
2963 */
2966 {
2969 /* cannot restart while nested */
2979 }
2980 /* protected by the BKL here */
2984 }
2986 /* this must be called inside a transaction, and requires the
2987 ** kernel_lock to be held
2988 */
2990 {
2996 }
2998 /* this must be called without a transaction started, and does not
2999 ** require BKL
3000 */
3002 {
3006 }
3008 /* this must be called without a transaction started, and does not
3009 ** require BKL
3010 */
3012 {
3016 }
3019 {
3020 wait_queue_t wait;
3024 /*
3025 * we don't want to use wait_event here because
3026 * we only want to wait once.
3027 */
3035 }
3038 }
3041 {
3045 }
3048 {
3060 }
3066 }
3067 }
3069 /* join == true if you must join an existing transaction.
3070 ** join == false if you can deal with waiting for others to finish
3071 **
3072 ** this will block until the transaction is joinable. send the number of blocks you
3073 ** expect to use in nblocks.
3074 */
3078 {
3090 /* set here for journal_join */
3094 relock:
3100 }
3110 }
3113 /* if there is no room in the journal OR
3114 ** if this transaction is too old, and we weren't called joinable, wait for it to finish before beginning
3115 ** we don't sleep if there aren't other writers
3116 */
3119 (!join
3136 sched_count++;
3139 }
3140 }
3141 /* don't mess with joining the transaction if all we have to do is
3142 * wait for someone else to do a commit
3143 */
3148 }
3150 }
3155 /* someone might have ended the transaction while we joined */
3160 }
3167 }
3168 /* we are the first writer, set trans_id */
3171 }
3182 out_fail:
3184 /* Re-set th->t_super, so we can properly keep track of how many
3185 * persistent transactions there are. We need to do this so if this
3186 * call is part of a failed restart_transaction, we can free it later */
3189 }
3192 super_block
3195 {
3199 /* if we're nesting into an existing transaction. It will be
3200 ** persistent on its own
3201 */
3208 }
3216 }
3220 }
3223 {
3228 else
3233 }
3235 }
3239 {
3242 /* this keeps do_journal_end from NULLing out the current->journal_info
3243 ** pointer
3244 */
3248 }
3252 {
3255 /* this keeps do_journal_end from NULLing out the current->journal_info
3256 ** pointer
3257 */
3261 }
3265 {
3271 /* we are nesting into the current transaction */
3278 "BAD: refcount <= 1, but "
3282 /* we've ended up with a handle from a different filesystem.
3283 ** save it and restore on journal_end. This should never
3284 ** really happen...
3285 */
3290 }
3293 }
3297 /* I guess this boils down to being the reciprocal of clm-2100 above.
3298 * If do_journal_begin_r fails, we need to put it back, since journal_end
3299 * won't be called to do it. */
3302 else
3306 }
3308 /*
3309 ** puts bh into the current transaction. If it was already there, reorders removes the
3310 ** old pointers from the hash, and puts new ones in (to make sure replay happen in the right order).
3311 **
3312 ** if it was dirty, cleans and files onto the clean list. I can't let it be dirty again until the
3313 ** transaction is committed.
3314 **
3315 ** if j_len, is bigger than j_len_alloc, it pushes j_len_alloc to 10 + j_len.
3316 */
3319 {
3331 }
3337 /* already in this transaction, we are done */
3341 }
3343 /* this must be turned into a panic instead of a warning. We can't allow
3344 ** a dirty or journal_dirty or locked buffer to be logged, as some changes
3345 ** could get to disk too early. NOT GOOD.
3346 */
3349 "buffer %llu bad state "
3356 }
3363 }
3364 /* this error means I've screwed up, and we've overflowed the transaction.
3365 ** Nothing can be done here, except make the FS readonly or panic.
3366 */
3371 }
3377 }
3381 }
3385 /* now put this guy on the end */
3390 }
3395 }
3406 }
3407 }
3417 }
3419 }
3423 {
3431 }
3438 /* we aren't allowed to close a nested transaction on a different
3439 ** filesystem from the one in the task struct
3440 */
3446 }
3450 }
3451 }
3453 /* removes from the current transaction, relsing and descrementing any counters.
3454 ** also files the removed buffer directly onto the clean list
3455 **
3456 ** called by journal_mark_freed when a block has been deleted
3457 **
3458 ** returns 1 if it cleaned and relsed the buffer. 0 otherwise
3459 */
3462 {
3471 }
3475 }
3478 }
3481 }
3484 }
3498 }
3500 }
3505 }
3507 /*
3508 ** for any cnode in a journal list, it can only be dirtied of all the
3509 ** transactions that include it are committed to disk.
3510 ** this checks through each transaction, and returns 1 if you are allowed to dirty,
3511 ** and 0 if you aren't
3512 **
3513 ** it is called by dirty_journal_list, which is called after flush_commit_list has gotten all the log
3514 ** blocks for a given transaction on disk
3515 **
3516 */
3518 {
3524 /* first test hprev. These are all newer than cn, so any node here
3525 ** with the same block number and dev means this node can't be sent
3526 ** to disk right now.
3527 */
3532 }
3534 }
3535 /* then test hnext. These are all older than cn. As long as they
3536 ** are committed to the log, it is safe to write cn to disk
3537 */
3544 }
3546 }
3548 }
3550 /* syncs the commit blocks, but does not force the real buffers to disk
3551 ** will wait until the current transaction is done/committed before returning
3552 */
3555 {
3559 /* you can sync while nested, very, very bad */
3565 }
3567 }
3569 /*
3570 ** writeback the pending async commits to disk
3571 */
3573 {
3582 /* last entry is the youngest, commit it and you get everything */
3586 }
3588 }
3590 /*
3591 ** flushes any old transactions to disk
3592 ** ends the current transaction if it is too old
3593 */
3595 {
3601 /* safety check so we don't flush while we are replaying the log during
3602 * mount
3603 */
3606 }
3608 /* check the current transaction. If there are no writers, and it is
3609 * too old, finish it, and force the commit blocks to disk
3610 */
3622 /* we're only being called from kreiserfsd, it makes no sense to do
3623 ** an async commit so that kreiserfsd can do it later
3624 */
3626 }
3627 }
3629 }
3631 /*
3632 ** returns 0 if do_journal_end should return right away, returns 1 if do_journal_end should finish the commit
3633 **
3634 ** if the current transaction is too old, but still has writers, this will wait on j_join_wait until all
3635 ** the writers are done. By the time it wakes up, the transaction it was called has already ended, so it just
3636 ** flushes the commit list and returns 0.
3637 **
3638 ** Won't batch when flush or commit_now is set. Also won't batch when others are waiting on j_join_wait.
3639 **
3640 ** Note, we can't allow the journal_end to proceed while there are still writers in the log.
3641 */
3645 {
3660 }
3663 if (atomic_read(&(journal->j_wcount)) > 0) { /* <= 0 is allowed. unmounting might not call begin */
3665 }
3667 /* BUG, deal with case where j_len is 0, but people previously freed blocks need to be released
3668 ** will be dealt with by next transaction that actually writes something, but should be taken
3669 ** care of in this trans
3670 */
3673 /* if wcount > 0, and we are called to with flush or commit_now,
3674 ** we wait on j_join_wait. We will wake up when the last writer has
3675 ** finished the transaction, and started it on its way to the disk.
3676 ** Then, we flush the commit or journal list, and just return 0
3677 ** because the rest of journal end was already done for this transaction.
3678 */
3690 }
3693 /* sleep while the current transaction is still j_jlocked */
3702 }
3704 }
3705 }
3712 }
3714 }
3717 }
3719 /* deal with old transactions where we are the last writers */
3724 }
3725 /* don't batch when someone is waiting on j_join_wait */
3726 /* don't batch when syncing the commit or flushing the whole trans */
3734 }
3740 }
3742 }
3744 /*
3745 ** Does all the work that makes deleting blocks safe.
3746 ** when deleting a block mark BH_JNew, just remove it from the current transaction, clean it's buffer_head and move on.
3747 **
3748 ** otherwise:
3749 ** set a bit for the block in the journal bitmap. That will prevent it from being allocated for unformatted nodes
3750 ** before this transaction has finished.
3751 **
3752 ** mark any cnodes for this block as BLOCK_FREED, and clear their bh pointers. That will prevent any old transactions with
3753 ** this block from trying to flush to the real location. Since we aren't removing the cnode from the journal_list_hash,
3754 ** the block can't be reallocated yet.
3755 **
3756 ** Then remove it from the current transaction, decrementing any counters and filing it on the clean list.
3757 */
3760 {
3772 }
3773 /* if it is journal new, we just remove it from this transaction */
3780 /* set the bit for this block in the journal bitmap for this transaction */
3785 }
3788 /* Note, the entire while loop is not allowed to schedule. */
3793 }
3796 /* find all older transactions with this block, make sure they don't try to write it out */
3798 blocknr);
3804 /* remove_from_transaction will brelse the buffer if it was
3805 ** in the current trans
3806 */
3808 bh);
3811 bh);
3819 }
3820 }
3824 j_nonzerolen));
3825 }
3827 }
3828 }
3830 }
3831 }
3836 }
3839 {
3843 }
3845 /*
3846 * returns -1 on error, 0 if no commits/barriers were done and 1
3847 * if a transaction was actually committed and the barrier was done
3848 */
3851 {
3857 /* is it from the current transaction, or from an unknown transaction? */
3860 /* try to let other writers come in and grow this transaction */
3864 }
3870 /* someone might have ended this transaction while we joined */
3877 }
3884 /* this gets tricky, we have to make sure the journal list in
3885 * the inode still exists. We know the list is still around
3886 * if we've got a larger transaction id than the oldest list
3887 */
3888 flush_commit_only:
3890 /*
3891 * we only set ret to 1 when we know for sure
3892 * the barrier hasn't been started yet on the commit
3893 * block.
3894 */
3900 }
3901 }
3902 /* otherwise the list is gone, and long since committed */
3904 }
3907 {
3911 /* for the whole inode, assume unset id means it was
3912 * changed in the current transaction. More conservative
3913 */
3917 /* jl will be updated in __commit_trans_jl */
3918 }
3921 }
3925 {
3930 }
3940 }
3941 }
3943 }
3946 /*
3947 ** before we can change a metadata block, we have to make sure it won't
3948 ** be written to disk while we are altering it. So, we must:
3949 ** clean it
3950 ** wait on it.
3951 **
3952 */
3955 {
3962 }
3967 }
3970 }
3973 {
3982 /* this check should always be run, to send old lists to disk */
3989 }
3990 }
3991 }
3993 /*
3994 ** long and ugly. If flush, will not return until all commit
3995 ** blocks and all real buffers in the trans are on disk.
3996 ** If no_async, won't return until all commit blocks are on disk.
3997 **
3998 ** keep reading, there are comments as you go along
3999 **
4000 ** If the journal is aborted, we just clean up. Things like flushing
4001 ** journal lists, etc just won't happen.
4002 */
4006 {
4028 /* protect flush_older_commits from doing mistakes if the
4029 transaction ID counter gets overflowed. */
4042 }
4048 }
4052 }
4054 /* check_journal_end locks the journal, and unlocks if it does not return 1
4055 ** it tells us if we should continue with the journal_end, or just return
4056 */
4062 }
4064 /* check_journal_end might set these, check again */
4067 }
4069 /*
4070 ** j must wait means we have to flush the log blocks, and the real blocks for
4071 ** this transaction
4072 */
4075 }
4076 #ifdef REISERFS_PREALLOCATE
4077 /* quota ops might need to nest, setup the journal_info pointer for them
4078 * and raise the refcount so that it is > 0. */
4082 * the transaction */
4085 #endif
4087 /* setup description block */
4088 d_bh =
4098 /* setup commit block. Don't write (keep it clean too) this one until after everyone else is written */
4107 /* init this journal list */
4110 /* we lock the commit before doing anything because
4111 * we want to make sure nobody tries to run flush_commit_list until
4112 * the new transaction is fully setup, and we've already flushed the
4113 * ordered bh list
4114 */
4117 /* save the transaction id in case we need to commit it later */
4130 /* The ENTIRE FOR LOOP MUST not cause schedule to occur.
4131 ** for each real block, add it to the journal list hash,
4132 ** copy into real block index array in the commit or desc block
4133 */
4141 }
4144 }
4149 }
4151 /* make sure the block we are trying to log is not a block
4152 of journal or reserved area */
4157 "Trying to log block %lu, "
4160 }
4173 }
4175 i--;
4176 }
4177 }
4183 /* special check in case all buffers in the journal were marked for not logging */
4186 /* we're about to dirty all the log blocks, mark the description block
4187 * dirty now too. Don't mark the commit block dirty until all the
4188 * others are on disk
4189 */
4192 /* first data block is j_start + 1, so add one to cur_write_start wherever you use it */
4198 /* copy all the real blocks into log area. dirty log blocks */
4203 tmp_bh =
4207 jindex) %
4217 jindex++;
4221 /* JDirty cleared sometime during transaction. don't log this one */
4223 "BAD, buffer in journal hash, "
4226 }
4233 }
4235 /* we are done with both the c_bh and d_bh, but
4236 ** c_bh must be written after all other commit blocks,
4237 ** so we dirty/relse c_bh in flush_commit_list, with commit_left <= 1.
4238 */
4242 /* now it is safe to insert this transaction on the main list */
4247 /* reset journal values for the next transaction */
4258 /* check for trans_id overflow */
4268 // make sure reiserfs_add_jh sees the new current_jl before we
4269 // write out the tails
4272 /* tail conversion targets have to hit the disk before we end the
4273 * transaction. Otherwise a later transaction might repack the tail
4274 * before this transaction commits, leaving the data block unflushed and
4275 * clean, if we crash before the later transaction commits, the data block
4276 * is lost.
4277 */
4283 }
4287 /* honor the flush wishes from the caller, simple commits can
4288 ** be done outside the journal lock, they are done below
4289 **
4290 ** if we don't flush the commit list right now, we put it into
4291 ** the work queue so the people waiting on the async progress work
4292 ** queue don't wait for this proc to flush journal lists and such.
4293 */
4300 /* if the next transaction has any chance of wrapping, flush
4301 ** transactions that might get overwritten. If any journal lists are very
4302 ** old flush them as well.
4303 */
4304 first_jl:
4315 /* if we don't cross into the next transaction and we don't
4316 * wrap, there is no way we can overlap any later transactions
4317 * break now
4318 */
4320 }
4330 /* we don't overlap anything from out start to the end of the
4331 * log, and our wrapped portion doesn't overlap anything at
4332 * the start of the log. We can break
4333 */
4335 }
4336 }
4337 }
4346 }
4350 /* wake up any body waiting to join. */
4357 }
4358 out:
4362 /* Re-set th->t_super, so we can properly keep track of how many
4363 * persistent transactions there are. We need to do this so if this
4364 * call is part of a failed restart_transaction, we can free it later */
4368 }
4370 /* Send the file system read only and refuse new transactions */
4372 {
4383 #ifdef CONFIG_REISERFS_CHECK
4385 #endif
4386 }