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1 /*
2 ** Write ahead logging implementation copyright Chris Mason 2000
3 **
4 ** The background commits make this code very interrelated, 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 */
36
37 #include <linux/time.h>
38 #include <linux/semaphore.h>
39 #include <linux/vmalloc.h>
40 #include "reiserfs.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/buffer_head.h>
47 #include <linux/workqueue.h>
48 #include <linux/writeback.h>
49 #include <linux/blkdev.h>
50 #include <linux/backing-dev.h>
51 #include <linux/uaccess.h>
52 #include <linux/slab.h>
53
54
55 /* gets a struct reiserfs_journal_list * from a list head */
56 #define JOURNAL_LIST_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
57                                j_list))
58 #define JOURNAL_WORK_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
59                                j_working_list))
60
61 /* the number of mounted filesystems.  This is used to decide when to
62 ** start and kill the commit workqueue
63 */
64 static int reiserfs_mounted_fs_count;
65
66 static struct workqueue_struct *commit_wq;
67
68 #define JOURNAL_TRANS_HALF 1018 /* must be correct to keep the desc and commit
69                                    structs at 4k */
70 #define BUFNR 64                /*read ahead */
71
72 /* cnode stat bits.  Move these into reiserfs_fs.h */
73
74 #define BLOCK_FREED 2           /* this block was freed, and can't be written.  */
75 #define BLOCK_FREED_HOLDER 3    /* this block was freed during this transaction, and can't be written */
76
77 #define BLOCK_NEEDS_FLUSH 4     /* used in flush_journal_list */
78 #define BLOCK_DIRTIED 5
79
80 /* journal list state bits */
81 #define LIST_TOUCHED 1
82 #define LIST_DIRTY   2
83 #define LIST_COMMIT_PENDING  4  /* someone will commit this list */
84
85 /* flags for do_journal_end */
86 #define FLUSH_ALL   1           /* flush commit and real blocks */
87 #define COMMIT_NOW  2           /* end and commit this transaction */
88 #define WAIT        4           /* wait for the log blocks to hit the disk */
89
90 static int do_journal_end(struct reiserfs_transaction_handle *,
91                           struct super_block *, unsigned long nblocks,
92                           int flags);
93 static int flush_journal_list(struct super_block *s,
94                               struct reiserfs_journal_list *jl, int flushall);
95 static int flush_commit_list(struct super_block *s,
96                              struct reiserfs_journal_list *jl, int flushall);
97 static int can_dirty(struct reiserfs_journal_cnode *cn);
98 static int journal_join(struct reiserfs_transaction_handle *th,
99                         struct super_block *sb, unsigned long nblocks);
100 static void release_journal_dev(struct super_block *super,
101                                struct reiserfs_journal *journal);
102 static int dirty_one_transaction(struct super_block *s,
103                                  struct reiserfs_journal_list *jl);
104 static void flush_async_commits(struct work_struct *work);
105 static void queue_log_writer(struct super_block *s);
106
107 /* values for join in do_journal_begin_r */
108 enum {
109         JBEGIN_REG = 0,         /* regular journal begin */
110         JBEGIN_JOIN = 1,        /* join the running transaction if at all possible */
111         JBEGIN_ABORT = 2,       /* called from cleanup code, ignores aborted flag */
112 };
113
114 static int do_journal_begin_r(struct reiserfs_transaction_handle *th,
115                               struct super_block *sb,
116                               unsigned long nblocks, int join);
117
118 static void init_journal_hash(struct super_block *sb)
119 {
120         struct reiserfs_journal *journal = SB_JOURNAL(sb);
121         memset(journal->j_hash_table, 0,
122                JOURNAL_HASH_SIZE * sizeof(struct reiserfs_journal_cnode *));
123 }
124
125 /*
126 ** clears BH_Dirty and sticks the buffer on the clean list.  Called because I can't allow refile_buffer to
127 ** make schedule happen after I've freed a block.  Look at remove_from_transaction and journal_mark_freed for
128 ** more details.
129 */
130 static int reiserfs_clean_and_file_buffer(struct buffer_head *bh)
131 {
132         if (bh) {
133                 clear_buffer_dirty(bh);
134                 clear_buffer_journal_test(bh);
135         }
136         return 0;
137 }
138
139 static struct reiserfs_bitmap_node *allocate_bitmap_node(struct super_block
140                                                          *sb)
141 {
142         struct reiserfs_bitmap_node *bn;
143         static int id;
144
145         bn = kmalloc(sizeof(struct reiserfs_bitmap_node), GFP_NOFS);
146         if (!bn) {
147                 return NULL;
148         }
149         bn->data = kzalloc(sb->s_blocksize, GFP_NOFS);
150         if (!bn->data) {
151                 kfree(bn);
152                 return NULL;
153         }
154         bn->id = id++;
155         INIT_LIST_HEAD(&bn->list);
156         return bn;
157 }
158
159 static struct reiserfs_bitmap_node *get_bitmap_node(struct super_block *sb)
160 {
161         struct reiserfs_journal *journal = SB_JOURNAL(sb);
162         struct reiserfs_bitmap_node *bn = NULL;
163         struct list_head *entry = journal->j_bitmap_nodes.next;
164
165         journal->j_used_bitmap_nodes++;
166       repeat:
167
168         if (entry != &journal->j_bitmap_nodes) {
169                 bn = list_entry(entry, struct reiserfs_bitmap_node, list);
170                 list_del(entry);
171                 memset(bn->data, 0, sb->s_blocksize);
172                 journal->j_free_bitmap_nodes--;
173                 return bn;
174         }
175         bn = allocate_bitmap_node(sb);
176         if (!bn) {
177                 yield();
178                 goto repeat;
179         }
180         return bn;
181 }
182 static inline void free_bitmap_node(struct super_block *sb,
183                                     struct reiserfs_bitmap_node *bn)
184 {
185         struct reiserfs_journal *journal = SB_JOURNAL(sb);
186         journal->j_used_bitmap_nodes--;
187         if (journal->j_free_bitmap_nodes > REISERFS_MAX_BITMAP_NODES) {
188                 kfree(bn->data);
189                 kfree(bn);
190         } else {
191                 list_add(&bn->list, &journal->j_bitmap_nodes);
192                 journal->j_free_bitmap_nodes++;
193         }
194 }
195
196 static void allocate_bitmap_nodes(struct super_block *sb)
197 {
198         int i;
199         struct reiserfs_journal *journal = SB_JOURNAL(sb);
200         struct reiserfs_bitmap_node *bn = NULL;
201         for (i = 0; i < REISERFS_MIN_BITMAP_NODES; i++) {
202                 bn = allocate_bitmap_node(sb);
203                 if (bn) {
204                         list_add(&bn->list, &journal->j_bitmap_nodes);
205                         journal->j_free_bitmap_nodes++;
206                 } else {
207                         break;  /* this is ok, we'll try again when more are needed */
208                 }
209         }
210 }
211
212 static int set_bit_in_list_bitmap(struct super_block *sb,
213                                   b_blocknr_t block,
214                                   struct reiserfs_list_bitmap *jb)
215 {
216         unsigned int bmap_nr = block / (sb->s_blocksize << 3);
217         unsigned int bit_nr = block % (sb->s_blocksize << 3);
218
219         if (!jb->bitmaps[bmap_nr]) {
220                 jb->bitmaps[bmap_nr] = get_bitmap_node(sb);
221         }
222         set_bit(bit_nr, (unsigned long *)jb->bitmaps[bmap_nr]->data);
223         return 0;
224 }
225
226 static void cleanup_bitmap_list(struct super_block *sb,
227                                 struct reiserfs_list_bitmap *jb)
228 {
229         int i;
230         if (jb->bitmaps == NULL)
231                 return;
232
233         for (i = 0; i < reiserfs_bmap_count(sb); i++) {
234                 if (jb->bitmaps[i]) {
235                         free_bitmap_node(sb, jb->bitmaps[i]);
236                         jb->bitmaps[i] = NULL;
237                 }
238         }
239 }
240
241 /*
242 ** only call this on FS unmount.
243 */
244 static int free_list_bitmaps(struct super_block *sb,
245                              struct reiserfs_list_bitmap *jb_array)
246 {
247         int i;
248         struct reiserfs_list_bitmap *jb;
249         for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
250                 jb = jb_array + i;
251                 jb->journal_list = NULL;
252                 cleanup_bitmap_list(sb, jb);
253                 vfree(jb->bitmaps);
254                 jb->bitmaps = NULL;
255         }
256         return 0;
257 }
258
259 static int free_bitmap_nodes(struct super_block *sb)
260 {
261         struct reiserfs_journal *journal = SB_JOURNAL(sb);
262         struct list_head *next = journal->j_bitmap_nodes.next;
263         struct reiserfs_bitmap_node *bn;
264
265         while (next != &journal->j_bitmap_nodes) {
266                 bn = list_entry(next, struct reiserfs_bitmap_node, list);
267                 list_del(next);
268                 kfree(bn->data);
269                 kfree(bn);
270                 next = journal->j_bitmap_nodes.next;
271                 journal->j_free_bitmap_nodes--;
272         }
273
274         return 0;
275 }
276
277 /*
278 ** get memory for JOURNAL_NUM_BITMAPS worth of bitmaps.
279 ** jb_array is the array to be filled in.
280 */
281 int reiserfs_allocate_list_bitmaps(struct super_block *sb,
282                                    struct reiserfs_list_bitmap *jb_array,
283                                    unsigned int bmap_nr)
284 {
285         int i;
286         int failed = 0;
287         struct reiserfs_list_bitmap *jb;
288         int mem = bmap_nr * sizeof(struct reiserfs_bitmap_node *);
289
290         for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
291                 jb = jb_array + i;
292                 jb->journal_list = NULL;
293                 jb->bitmaps = vzalloc(mem);
294                 if (!jb->bitmaps) {
295                         reiserfs_warning(sb, "clm-2000", "unable to "
296                                          "allocate bitmaps for journal lists");
297                         failed = 1;
298                         break;
299                 }
300         }
301         if (failed) {
302                 free_list_bitmaps(sb, jb_array);
303                 return -1;
304         }
305         return 0;
306 }
307
308 /*
309 ** find an available list bitmap.  If you can't find one, flush a commit list
310 ** and try again
311 */
312 static struct reiserfs_list_bitmap *get_list_bitmap(struct super_block *sb,
313                                                     struct reiserfs_journal_list
314                                                     *jl)
315 {
316         int i, j;
317         struct reiserfs_journal *journal = SB_JOURNAL(sb);
318         struct reiserfs_list_bitmap *jb = NULL;
319
320         for (j = 0; j < (JOURNAL_NUM_BITMAPS * 3); j++) {
321                 i = journal->j_list_bitmap_index;
322                 journal->j_list_bitmap_index = (i + 1) % JOURNAL_NUM_BITMAPS;
323                 jb = journal->j_list_bitmap + i;
324                 if (journal->j_list_bitmap[i].journal_list) {
325                         flush_commit_list(sb,
326                                           journal->j_list_bitmap[i].
327                                           journal_list, 1);
328                         if (!journal->j_list_bitmap[i].journal_list) {
329                                 break;
330                         }
331                 } else {
332                         break;
333                 }
334         }
335         if (jb->journal_list) { /* double check to make sure if flushed correctly */
336                 return NULL;
337         }
338         jb->journal_list = jl;
339         return jb;
340 }
341
342 /*
343 ** allocates a new chunk of X nodes, and links them all together as a list.
344 ** Uses the cnode->next and cnode->prev pointers
345 ** returns NULL on failure
346 */
347 static struct reiserfs_journal_cnode *allocate_cnodes(int num_cnodes)
348 {
349         struct reiserfs_journal_cnode *head;
350         int i;
351         if (num_cnodes <= 0) {
352                 return NULL;
353         }
354         head = vzalloc(num_cnodes * sizeof(struct reiserfs_journal_cnode));
355         if (!head) {
356                 return NULL;
357         }
358         head[0].prev = NULL;
359         head[0].next = head + 1;
360         for (i = 1; i < num_cnodes; i++) {
361                 head[i].prev = head + (i - 1);
362                 head[i].next = head + (i + 1);  /* if last one, overwrite it after the if */
363         }
364         head[num_cnodes - 1].next = NULL;
365         return head;
366 }
367
368 /*
369 ** pulls a cnode off the free list, or returns NULL on failure
370 */
371 static struct reiserfs_journal_cnode *get_cnode(struct super_block *sb)
372 {
373         struct reiserfs_journal_cnode *cn;
374         struct reiserfs_journal *journal = SB_JOURNAL(sb);
375
376         reiserfs_check_lock_depth(sb, "get_cnode");
377
378         if (journal->j_cnode_free <= 0) {
379                 return NULL;
380         }
381         journal->j_cnode_used++;
382         journal->j_cnode_free--;
383         cn = journal->j_cnode_free_list;
384         if (!cn) {
385                 return cn;
386         }
387         if (cn->next) {
388                 cn->next->prev = NULL;
389         }
390         journal->j_cnode_free_list = cn->next;
391         memset(cn, 0, sizeof(struct reiserfs_journal_cnode));
392         return cn;
393 }
394
395 /*
396 ** returns a cnode to the free list
397 */
398 static void free_cnode(struct super_block *sb,
399                        struct reiserfs_journal_cnode *cn)
400 {
401         struct reiserfs_journal *journal = SB_JOURNAL(sb);
402
403         reiserfs_check_lock_depth(sb, "free_cnode");
404
405         journal->j_cnode_used--;
406         journal->j_cnode_free++;
407         /* memset(cn, 0, sizeof(struct reiserfs_journal_cnode)) ; */
408         cn->next = journal->j_cnode_free_list;
409         if (journal->j_cnode_free_list) {
410                 journal->j_cnode_free_list->prev = cn;
411         }
412         cn->prev = NULL;        /* not needed with the memset, but I might kill the memset, and forget to do this */
413         journal->j_cnode_free_list = cn;
414 }
415
416 static void clear_prepared_bits(struct buffer_head *bh)
417 {
418         clear_buffer_journal_prepared(bh);
419         clear_buffer_journal_restore_dirty(bh);
420 }
421
422 /* return a cnode with same dev, block number and size in table, or null if not found */
423 static inline struct reiserfs_journal_cnode *get_journal_hash_dev(struct
424                                                                   super_block
425                                                                   *sb,
426                                                                   struct
427                                                                   reiserfs_journal_cnode
428                                                                   **table,
429                                                                   long bl)
430 {
431         struct reiserfs_journal_cnode *cn;
432         cn = journal_hash(table, sb, bl);
433         while (cn) {
434                 if (cn->blocknr == bl && cn->sb == sb)
435                         return cn;
436                 cn = cn->hnext;
437         }
438         return (struct reiserfs_journal_cnode *)0;
439 }
440
441 /*
442 ** this actually means 'can this block be reallocated yet?'.  If you set search_all, a block can only be allocated
443 ** if it is not in the current transaction, was not freed by the current transaction, and has no chance of ever
444 ** being overwritten by a replay after crashing.
445 **
446 ** If you don't set search_all, a block can only be allocated if it is not in the current transaction.  Since deleting
447 ** a block removes it from the current transaction, this case should never happen.  If you don't set search_all, make
448 ** sure you never write the block without logging it.
449 **
450 ** next_zero_bit is a suggestion about the next block to try for find_forward.
451 ** when bl is rejected because it is set in a journal list bitmap, we search
452 ** for the next zero bit in the bitmap that rejected bl.  Then, we return that
453 ** through next_zero_bit for find_forward to try.
454 **
455 ** Just because we return something in next_zero_bit does not mean we won't
456 ** reject it on the next call to reiserfs_in_journal
457 **
458 */
459 int reiserfs_in_journal(struct super_block *sb,
460                         unsigned int bmap_nr, int bit_nr, int search_all,
461                         b_blocknr_t * next_zero_bit)
462 {
463         struct reiserfs_journal *journal = SB_JOURNAL(sb);
464         struct reiserfs_journal_cnode *cn;
465         struct reiserfs_list_bitmap *jb;
466         int i;
467         unsigned long bl;
468
469         *next_zero_bit = 0;     /* always start this at zero. */
470
471         PROC_INFO_INC(sb, journal.in_journal);
472         /* If we aren't doing a search_all, this is a metablock, and it will be logged before use.
473          ** if we crash before the transaction that freed it commits,  this transaction won't
474          ** have committed either, and the block will never be written
475          */
476         if (search_all) {
477                 for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
478                         PROC_INFO_INC(sb, journal.in_journal_bitmap);
479                         jb = journal->j_list_bitmap + i;
480                         if (jb->journal_list && jb->bitmaps[bmap_nr] &&
481                             test_bit(bit_nr,
482                                      (unsigned long *)jb->bitmaps[bmap_nr]->
483                                      data)) {
484                                 *next_zero_bit =
485                                     find_next_zero_bit((unsigned long *)
486                                                        (jb->bitmaps[bmap_nr]->
487                                                         data),
488                                                        sb->s_blocksize << 3,
489                                                        bit_nr + 1);
490                                 return 1;
491                         }
492                 }
493         }
494
495         bl = bmap_nr * (sb->s_blocksize << 3) + bit_nr;
496         /* is it in any old transactions? */
497         if (search_all
498             && (cn =
499                 get_journal_hash_dev(sb, journal->j_list_hash_table, bl))) {
500                 return 1;
501         }
502
503         /* is it in the current transaction.  This should never happen */
504         if ((cn = get_journal_hash_dev(sb, journal->j_hash_table, bl))) {
505                 BUG();
506                 return 1;
507         }
508
509         PROC_INFO_INC(sb, journal.in_journal_reusable);
510         /* safe for reuse */
511         return 0;
512 }
513
514 /* insert cn into table
515 */
516 static inline void insert_journal_hash(struct reiserfs_journal_cnode **table,
517                                        struct reiserfs_journal_cnode *cn)
518 {
519         struct reiserfs_journal_cnode *cn_orig;
520
521         cn_orig = journal_hash(table, cn->sb, cn->blocknr);
522         cn->hnext = cn_orig;
523         cn->hprev = NULL;
524         if (cn_orig) {
525                 cn_orig->hprev = cn;
526         }
527         journal_hash(table, cn->sb, cn->blocknr) = cn;
528 }
529
530 /* lock the current transaction */
531 static inline void lock_journal(struct super_block *sb)
532 {
533         PROC_INFO_INC(sb, journal.lock_journal);
534
535         reiserfs_mutex_lock_safe(&SB_JOURNAL(sb)->j_mutex, sb);
536 }
537
538 /* unlock the current transaction */
539 static inline void unlock_journal(struct super_block *sb)
540 {
541         mutex_unlock(&SB_JOURNAL(sb)->j_mutex);
542 }
543
544 static inline void get_journal_list(struct reiserfs_journal_list *jl)
545 {
546         jl->j_refcount++;
547 }
548
549 static inline void put_journal_list(struct super_block *s,
550                                     struct reiserfs_journal_list *jl)
551 {
552         if (jl->j_refcount < 1) {
553                 reiserfs_panic(s, "journal-2", "trans id %u, refcount at %d",
554                                jl->j_trans_id, jl->j_refcount);
555         }
556         if (--jl->j_refcount == 0)
557                 kfree(jl);
558 }
559
560 /*
561 ** this used to be much more involved, and I'm keeping it just in case things get ugly again.
562 ** it gets called by flush_commit_list, and cleans up any data stored about blocks freed during a
563 ** transaction.
564 */
565 static void cleanup_freed_for_journal_list(struct super_block *sb,
566                                            struct reiserfs_journal_list *jl)
567 {
568
569         struct reiserfs_list_bitmap *jb = jl->j_list_bitmap;
570         if (jb) {
571                 cleanup_bitmap_list(sb, jb);
572         }
573         jl->j_list_bitmap->journal_list = NULL;
574         jl->j_list_bitmap = NULL;
575 }
576
577 static int journal_list_still_alive(struct super_block *s,
578                                     unsigned int trans_id)
579 {
580         struct reiserfs_journal *journal = SB_JOURNAL(s);
581         struct list_head *entry = &journal->j_journal_list;
582         struct reiserfs_journal_list *jl;
583
584         if (!list_empty(entry)) {
585                 jl = JOURNAL_LIST_ENTRY(entry->next);
586                 if (jl->j_trans_id <= trans_id) {
587                         return 1;
588                 }
589         }
590         return 0;
591 }
592
593 /*
594  * If page->mapping was null, we failed to truncate this page for
595  * some reason.  Most likely because it was truncated after being
596  * logged via data=journal.
597  *
598  * This does a check to see if the buffer belongs to one of these
599  * lost pages before doing the final put_bh.  If page->mapping was
600  * null, it tries to free buffers on the page, which should make the
601  * final page_cache_release drop the page from the lru.
602  */
603 static void release_buffer_page(struct buffer_head *bh)
604 {
605         struct page *page = bh->b_page;
606         if (!page->mapping && trylock_page(page)) {
607                 page_cache_get(page);
608                 put_bh(bh);
609                 if (!page->mapping)
610                         try_to_free_buffers(page);
611                 unlock_page(page);
612                 page_cache_release(page);
613         } else {
614                 put_bh(bh);
615         }
616 }
617
618 static void reiserfs_end_buffer_io_sync(struct buffer_head *bh, int uptodate)
619 {
620         char b[BDEVNAME_SIZE];
621
622         if (buffer_journaled(bh)) {
623                 reiserfs_warning(NULL, "clm-2084",
624                                  "pinned buffer %lu:%s sent to disk",
625                                  bh->b_blocknr, bdevname(bh->b_bdev, b));
626         }
627         if (uptodate)
628                 set_buffer_uptodate(bh);
629         else
630                 clear_buffer_uptodate(bh);
631
632         unlock_buffer(bh);
633         release_buffer_page(bh);
634 }
635
636 static void reiserfs_end_ordered_io(struct buffer_head *bh, int uptodate)
637 {
638         if (uptodate)
639                 set_buffer_uptodate(bh);
640         else
641                 clear_buffer_uptodate(bh);
642         unlock_buffer(bh);
643         put_bh(bh);
644 }
645
646 static void submit_logged_buffer(struct buffer_head *bh)
647 {
648         get_bh(bh);
649         bh->b_end_io = reiserfs_end_buffer_io_sync;
650         clear_buffer_journal_new(bh);
651         clear_buffer_dirty(bh);
652         if (!test_clear_buffer_journal_test(bh))
653                 BUG();
654         if (!buffer_uptodate(bh))
655                 BUG();
656         submit_bh(WRITE, bh);
657 }
658
659 static void submit_ordered_buffer(struct buffer_head *bh)
660 {
661         get_bh(bh);
662         bh->b_end_io = reiserfs_end_ordered_io;
663         clear_buffer_dirty(bh);
664         if (!buffer_uptodate(bh))
665                 BUG();
666         submit_bh(WRITE, bh);
667 }
668
669 #define CHUNK_SIZE 32
670 struct buffer_chunk {
671         struct buffer_head *bh[CHUNK_SIZE];
672         int nr;
673 };
674
675 static void write_chunk(struct buffer_chunk *chunk)
676 {
677         int i;
678         for (i = 0; i < chunk->nr; i++) {
679                 submit_logged_buffer(chunk->bh[i]);
680         }
681         chunk->nr = 0;
682 }
683
684 static void write_ordered_chunk(struct buffer_chunk *chunk)
685 {
686         int i;
687         for (i = 0; i < chunk->nr; i++) {
688                 submit_ordered_buffer(chunk->bh[i]);
689         }
690         chunk->nr = 0;
691 }
692
693 static int add_to_chunk(struct buffer_chunk *chunk, struct buffer_head *bh,
694                         spinlock_t * lock, void (fn) (struct buffer_chunk *))
695 {
696         int ret = 0;
697         BUG_ON(chunk->nr >= CHUNK_SIZE);
698         chunk->bh[chunk->nr++] = bh;
699         if (chunk->nr >= CHUNK_SIZE) {
700                 ret = 1;
701                 if (lock)
702                         spin_unlock(lock);
703                 fn(chunk);
704                 if (lock)
705                         spin_lock(lock);
706         }
707         return ret;
708 }
709
710 static atomic_t nr_reiserfs_jh = ATOMIC_INIT(0);
711 static struct reiserfs_jh *alloc_jh(void)
712 {
713         struct reiserfs_jh *jh;
714         while (1) {
715                 jh = kmalloc(sizeof(*jh), GFP_NOFS);
716                 if (jh) {
717                         atomic_inc(&nr_reiserfs_jh);
718                         return jh;
719                 }
720                 yield();
721         }
722 }
723
724 /*
725  * we want to free the jh when the buffer has been written
726  * and waited on
727  */
728 void reiserfs_free_jh(struct buffer_head *bh)
729 {
730         struct reiserfs_jh *jh;
731
732         jh = bh->b_private;
733         if (jh) {
734                 bh->b_private = NULL;
735                 jh->bh = NULL;
736                 list_del_init(&jh->list);
737                 kfree(jh);
738                 if (atomic_read(&nr_reiserfs_jh) <= 0)
739                         BUG();
740                 atomic_dec(&nr_reiserfs_jh);
741                 put_bh(bh);
742         }
743 }
744
745 static inline int __add_jh(struct reiserfs_journal *j, struct buffer_head *bh,
746                            int tail)
747 {
748         struct reiserfs_jh *jh;
749
750         if (bh->b_private) {
751                 spin_lock(&j->j_dirty_buffers_lock);
752                 if (!bh->b_private) {
753                         spin_unlock(&j->j_dirty_buffers_lock);
754                         goto no_jh;
755                 }
756                 jh = bh->b_private;
757                 list_del_init(&jh->list);
758         } else {
759               no_jh:
760                 get_bh(bh);
761                 jh = alloc_jh();
762                 spin_lock(&j->j_dirty_buffers_lock);
763                 /* buffer must be locked for __add_jh, should be able to have
764                  * two adds at the same time
765                  */
766                 BUG_ON(bh->b_private);
767                 jh->bh = bh;
768                 bh->b_private = jh;
769         }
770         jh->jl = j->j_current_jl;
771         if (tail)
772                 list_add_tail(&jh->list, &jh->jl->j_tail_bh_list);
773         else {
774                 list_add_tail(&jh->list, &jh->jl->j_bh_list);
775         }
776         spin_unlock(&j->j_dirty_buffers_lock);
777         return 0;
778 }
779
780 int reiserfs_add_tail_list(struct inode *inode, struct buffer_head *bh)
781 {
782         return __add_jh(SB_JOURNAL(inode->i_sb), bh, 1);
783 }
784 int reiserfs_add_ordered_list(struct inode *inode, struct buffer_head *bh)
785 {
786         return __add_jh(SB_JOURNAL(inode->i_sb), bh, 0);
787 }
788
789 #define JH_ENTRY(l) list_entry((l), struct reiserfs_jh, list)
790 static int write_ordered_buffers(spinlock_t * lock,
791                                  struct reiserfs_journal *j,
792                                  struct reiserfs_journal_list *jl,
793                                  struct list_head *list)
794 {
795         struct buffer_head *bh;
796         struct reiserfs_jh *jh;
797         int ret = j->j_errno;
798         struct buffer_chunk chunk;
799         struct list_head tmp;
800         INIT_LIST_HEAD(&tmp);
801
802         chunk.nr = 0;
803         spin_lock(lock);
804         while (!list_empty(list)) {
805                 jh = JH_ENTRY(list->next);
806                 bh = jh->bh;
807                 get_bh(bh);
808                 if (!trylock_buffer(bh)) {
809                         if (!buffer_dirty(bh)) {
810                                 list_move(&jh->list, &tmp);
811                                 goto loop_next;
812                         }
813                         spin_unlock(lock);
814                         if (chunk.nr)
815                                 write_ordered_chunk(&chunk);
816                         wait_on_buffer(bh);
817                         cond_resched();
818                         spin_lock(lock);
819                         goto loop_next;
820                 }
821                 /* in theory, dirty non-uptodate buffers should never get here,
822                  * but the upper layer io error paths still have a few quirks.
823                  * Handle them here as gracefully as we can
824                  */
825                 if (!buffer_uptodate(bh) && buffer_dirty(bh)) {
826                         clear_buffer_dirty(bh);
827                         ret = -EIO;
828                 }
829                 if (buffer_dirty(bh)) {
830                         list_move(&jh->list, &tmp);
831                         add_to_chunk(&chunk, bh, lock, write_ordered_chunk);
832                 } else {
833                         reiserfs_free_jh(bh);
834                         unlock_buffer(bh);
835                 }
836               loop_next:
837                 put_bh(bh);
838                 cond_resched_lock(lock);
839         }
840         if (chunk.nr) {
841                 spin_unlock(lock);
842                 write_ordered_chunk(&chunk);
843                 spin_lock(lock);
844         }
845         while (!list_empty(&tmp)) {
846                 jh = JH_ENTRY(tmp.prev);
847                 bh = jh->bh;
848                 get_bh(bh);
849                 reiserfs_free_jh(bh);
850
851                 if (buffer_locked(bh)) {
852                         spin_unlock(lock);
853                         wait_on_buffer(bh);
854                         spin_lock(lock);
855                 }
856                 if (!buffer_uptodate(bh)) {
857                         ret = -EIO;
858                 }
859                 /* ugly interaction with invalidatepage here.
860                  * reiserfs_invalidate_page will pin any buffer that has a valid
861                  * journal head from an older transaction.  If someone else sets
862                  * our buffer dirty after we write it in the first loop, and
863                  * then someone truncates the page away, nobody will ever write
864                  * the buffer. We're safe if we write the page one last time
865                  * after freeing the journal header.
866                  */
867                 if (buffer_dirty(bh) && unlikely(bh->b_page->mapping == NULL)) {
868                         spin_unlock(lock);
869                         ll_rw_block(WRITE, 1, &bh);
870                         spin_lock(lock);
871                 }
872                 put_bh(bh);
873                 cond_resched_lock(lock);
874         }
875         spin_unlock(lock);
876         return ret;
877 }
878
879 static int flush_older_commits(struct super_block *s,
880                                struct reiserfs_journal_list *jl)
881 {
882         struct reiserfs_journal *journal = SB_JOURNAL(s);
883         struct reiserfs_journal_list *other_jl;
884         struct reiserfs_journal_list *first_jl;
885         struct list_head *entry;
886         unsigned int trans_id = jl->j_trans_id;
887         unsigned int other_trans_id;
888         unsigned int first_trans_id;
889
890       find_first:
891         /*
892          * first we walk backwards to find the oldest uncommitted transation
893          */
894         first_jl = jl;
895         entry = jl->j_list.prev;
896         while (1) {
897                 other_jl = JOURNAL_LIST_ENTRY(entry);
898                 if (entry == &journal->j_journal_list ||
899                     atomic_read(&other_jl->j_older_commits_done))
900                         break;
901
902                 first_jl = other_jl;
903                 entry = other_jl->j_list.prev;
904         }
905
906         /* if we didn't find any older uncommitted transactions, return now */
907         if (first_jl == jl) {
908                 return 0;
909         }
910
911         first_trans_id = first_jl->j_trans_id;
912
913         entry = &first_jl->j_list;
914         while (1) {
915                 other_jl = JOURNAL_LIST_ENTRY(entry);
916                 other_trans_id = other_jl->j_trans_id;
917
918                 if (other_trans_id < trans_id) {
919                         if (atomic_read(&other_jl->j_commit_left) != 0) {
920                                 flush_commit_list(s, other_jl, 0);
921
922                                 /* list we were called with is gone, return */
923                                 if (!journal_list_still_alive(s, trans_id))
924                                         return 1;
925
926                                 /* the one we just flushed is gone, this means all
927                                  * older lists are also gone, so first_jl is no longer
928                                  * valid either.  Go back to the beginning.
929                                  */
930                                 if (!journal_list_still_alive
931                                     (s, other_trans_id)) {
932                                         goto find_first;
933                                 }
934                         }
935                         entry = entry->next;
936                         if (entry == &journal->j_journal_list)
937                                 return 0;
938                 } else {
939                         return 0;
940                 }
941         }
942         return 0;
943 }
944
945 static int reiserfs_async_progress_wait(struct super_block *s)
946 {
947         struct reiserfs_journal *j = SB_JOURNAL(s);
948
949         if (atomic_read(&j->j_async_throttle)) {
950                 int depth;
951
952                 depth = reiserfs_write_unlock_nested(s);
953                 congestion_wait(BLK_RW_ASYNC, HZ / 10);
954                 reiserfs_write_lock_nested(s, depth);
955         }
956
957         return 0;
958 }
959
960 /*
961 ** if this journal list still has commit blocks unflushed, send them to disk.
962 **
963 ** log areas must be flushed in order (transaction 2 can't commit before transaction 1)
964 ** Before the commit block can by written, every other log block must be safely on disk
965 **
966 */
967 static int flush_commit_list(struct super_block *s,
968                              struct reiserfs_journal_list *jl, int flushall)
969 {
970         int i;
971         b_blocknr_t bn;
972         struct buffer_head *tbh = NULL;
973         unsigned int trans_id = jl->j_trans_id;
974         struct reiserfs_journal *journal = SB_JOURNAL(s);
975         int retval = 0;
976         int write_len;
977         int depth;
978
979         reiserfs_check_lock_depth(s, "flush_commit_list");
980
981         if (atomic_read(&jl->j_older_commits_done)) {
982                 return 0;
983         }
984
985         /* before we can put our commit blocks on disk, we have to make sure everyone older than
986          ** us is on disk too
987          */
988         BUG_ON(jl->j_len <= 0);
989         BUG_ON(trans_id == journal->j_trans_id);
990
991         get_journal_list(jl);
992         if (flushall) {
993                 if (flush_older_commits(s, jl) == 1) {
994                         /* list disappeared during flush_older_commits.  return */
995                         goto put_jl;
996                 }
997         }
998
999         /* make sure nobody is trying to flush this one at the same time */
1000         reiserfs_mutex_lock_safe(&jl->j_commit_mutex, s);
1001
1002         if (!journal_list_still_alive(s, trans_id)) {
1003                 mutex_unlock(&jl->j_commit_mutex);
1004                 goto put_jl;
1005         }
1006         BUG_ON(jl->j_trans_id == 0);
1007
1008         /* this commit is done, exit */
1009         if (atomic_read(&(jl->j_commit_left)) <= 0) {
1010                 if (flushall) {
1011                         atomic_set(&(jl->j_older_commits_done), 1);
1012                 }
1013                 mutex_unlock(&jl->j_commit_mutex);
1014                 goto put_jl;
1015         }
1016
1017         if (!list_empty(&jl->j_bh_list)) {
1018                 int ret;
1019
1020                 /*
1021                  * We might sleep in numerous places inside
1022                  * write_ordered_buffers. Relax the write lock.
1023                  */
1024                 depth = reiserfs_write_unlock_nested(s);
1025                 ret = write_ordered_buffers(&journal->j_dirty_buffers_lock,
1026                                             journal, jl, &jl->j_bh_list);
1027                 if (ret < 0 && retval == 0)
1028                         retval = ret;
1029                 reiserfs_write_lock_nested(s, depth);
1030         }
1031         BUG_ON(!list_empty(&jl->j_bh_list));
1032         /*
1033          * for the description block and all the log blocks, submit any buffers
1034          * that haven't already reached the disk.  Try to write at least 256
1035          * log blocks. later on, we will only wait on blocks that correspond
1036          * to this transaction, but while we're unplugging we might as well
1037          * get a chunk of data on there.
1038          */
1039         atomic_inc(&journal->j_async_throttle);
1040         write_len = jl->j_len + 1;
1041         if (write_len < 256)
1042                 write_len = 256;
1043         for (i = 0 ; i < write_len ; i++) {
1044                 bn = SB_ONDISK_JOURNAL_1st_BLOCK(s) + (jl->j_start + i) %
1045                     SB_ONDISK_JOURNAL_SIZE(s);
1046                 tbh = journal_find_get_block(s, bn);
1047                 if (tbh) {
1048                         if (buffer_dirty(tbh)) {
1049                             depth = reiserfs_write_unlock_nested(s);
1050                             ll_rw_block(WRITE, 1, &tbh);
1051                             reiserfs_write_lock_nested(s, depth);
1052                         }
1053                         put_bh(tbh) ;
1054                 }
1055         }
1056         atomic_dec(&journal->j_async_throttle);
1057
1058         for (i = 0; i < (jl->j_len + 1); i++) {
1059                 bn = SB_ONDISK_JOURNAL_1st_BLOCK(s) +
1060                     (jl->j_start + i) % SB_ONDISK_JOURNAL_SIZE(s);
1061                 tbh = journal_find_get_block(s, bn);
1062
1063                 depth = reiserfs_write_unlock_nested(s);
1064                 __wait_on_buffer(tbh);
1065                 reiserfs_write_lock_nested(s, depth);
1066                 // since we're using ll_rw_blk above, it might have skipped over
1067                 // a locked buffer.  Double check here
1068                 //
1069                 /* redundant, sync_dirty_buffer() checks */
1070                 if (buffer_dirty(tbh)) {
1071                         depth = reiserfs_write_unlock_nested(s);
1072                         sync_dirty_buffer(tbh);
1073                         reiserfs_write_lock_nested(s, depth);
1074                 }
1075                 if (unlikely(!buffer_uptodate(tbh))) {
1076 #ifdef CONFIG_REISERFS_CHECK
1077                         reiserfs_warning(s, "journal-601",
1078                                          "buffer write failed");
1079 #endif
1080                         retval = -EIO;
1081                 }
1082                 put_bh(tbh);    /* once for journal_find_get_block */
1083                 put_bh(tbh);    /* once due to original getblk in do_journal_end */
1084                 atomic_dec(&(jl->j_commit_left));
1085         }
1086
1087         BUG_ON(atomic_read(&(jl->j_commit_left)) != 1);
1088
1089         /* If there was a write error in the journal - we can't commit
1090          * this transaction - it will be invalid and, if successful,
1091          * will just end up propagating the write error out to
1092          * the file system. */
1093         if (likely(!retval && !reiserfs_is_journal_aborted (journal))) {
1094                 if (buffer_dirty(jl->j_commit_bh))
1095                         BUG();
1096                 mark_buffer_dirty(jl->j_commit_bh) ;
1097                 depth = reiserfs_write_unlock_nested(s);
1098                 if (reiserfs_barrier_flush(s))
1099                         __sync_dirty_buffer(jl->j_commit_bh, WRITE_FLUSH_FUA);
1100                 else
1101                         sync_dirty_buffer(jl->j_commit_bh);
1102                 reiserfs_write_lock_nested(s, depth);
1103         }
1104
1105         /* If there was a write error in the journal - we can't commit this
1106          * transaction - it will be invalid and, if successful, will just end
1107          * up propagating the write error out to the filesystem. */
1108         if (unlikely(!buffer_uptodate(jl->j_commit_bh))) {
1109 #ifdef CONFIG_REISERFS_CHECK
1110                 reiserfs_warning(s, "journal-615", "buffer write failed");
1111 #endif
1112                 retval = -EIO;
1113         }
1114         bforget(jl->j_commit_bh);
1115         if (journal->j_last_commit_id != 0 &&
1116             (jl->j_trans_id - journal->j_last_commit_id) != 1) {
1117                 reiserfs_warning(s, "clm-2200", "last commit %lu, current %lu",
1118                                  journal->j_last_commit_id, jl->j_trans_id);
1119         }
1120         journal->j_last_commit_id = jl->j_trans_id;
1121
1122         /* now, every commit block is on the disk.  It is safe to allow blocks freed during this transaction to be reallocated */
1123         cleanup_freed_for_journal_list(s, jl);
1124
1125         retval = retval ? retval : journal->j_errno;
1126
1127         /* mark the metadata dirty */
1128         if (!retval)
1129                 dirty_one_transaction(s, jl);
1130         atomic_dec(&(jl->j_commit_left));
1131
1132         if (flushall) {
1133                 atomic_set(&(jl->j_older_commits_done), 1);
1134         }
1135         mutex_unlock(&jl->j_commit_mutex);
1136       put_jl:
1137         put_journal_list(s, jl);
1138
1139         if (retval)
1140                 reiserfs_abort(s, retval, "Journal write error in %s",
1141                                __func__);
1142         return retval;
1143 }
1144
1145 /*
1146 ** flush_journal_list frequently needs to find a newer transaction for a given block.  This does that, or
1147 ** returns NULL if it can't find anything
1148 */
1149 static struct reiserfs_journal_list *find_newer_jl_for_cn(struct
1150                                                           reiserfs_journal_cnode
1151                                                           *cn)
1152 {
1153         struct super_block *sb = cn->sb;
1154         b_blocknr_t blocknr = cn->blocknr;
1155
1156         cn = cn->hprev;
1157         while (cn) {
1158                 if (cn->sb == sb && cn->blocknr == blocknr && cn->jlist) {
1159                         return cn->jlist;
1160                 }
1161                 cn = cn->hprev;
1162         }
1163         return NULL;
1164 }
1165
1166 static int newer_jl_done(struct reiserfs_journal_cnode *cn)
1167 {
1168         struct super_block *sb = cn->sb;
1169         b_blocknr_t blocknr = cn->blocknr;
1170
1171         cn = cn->hprev;
1172         while (cn) {
1173                 if (cn->sb == sb && cn->blocknr == blocknr && cn->jlist &&
1174                     atomic_read(&cn->jlist->j_commit_left) != 0)
1175                                     return 0;
1176                 cn = cn->hprev;
1177         }
1178         return 1;
1179 }
1180
1181 static void remove_journal_hash(struct super_block *,
1182                                 struct reiserfs_journal_cnode **,
1183                                 struct reiserfs_journal_list *, unsigned long,
1184                                 int);
1185
1186 /*
1187 ** once all the real blocks have been flushed, it is safe to remove them from the
1188 ** journal list for this transaction.  Aside from freeing the cnode, this also allows the
1189 ** block to be reallocated for data blocks if it had been deleted.
1190 */
1191 static void remove_all_from_journal_list(struct super_block *sb,
1192                                          struct reiserfs_journal_list *jl,
1193                                          int debug)
1194 {
1195         struct reiserfs_journal *journal = SB_JOURNAL(sb);
1196         struct reiserfs_journal_cnode *cn, *last;
1197         cn = jl->j_realblock;
1198
1199         /* which is better, to lock once around the whole loop, or
1200          ** to lock for each call to remove_journal_hash?
1201          */
1202         while (cn) {
1203                 if (cn->blocknr != 0) {
1204                         if (debug) {
1205                                 reiserfs_warning(sb, "reiserfs-2201",
1206                                                  "block %u, bh is %d, state %ld",
1207                                                  cn->blocknr, cn->bh ? 1 : 0,
1208                                                  cn->state);
1209                         }
1210                         cn->state = 0;
1211                         remove_journal_hash(sb, journal->j_list_hash_table,
1212                                             jl, cn->blocknr, 1);
1213                 }
1214                 last = cn;
1215                 cn = cn->next;
1216                 free_cnode(sb, last);
1217         }
1218         jl->j_realblock = NULL;
1219 }
1220
1221 /*
1222 ** if this timestamp is greater than the timestamp we wrote last to the header block, write it to the header block.
1223 ** once this is done, I can safely say the log area for this transaction won't ever be replayed, and I can start
1224 ** releasing blocks in this transaction for reuse as data blocks.
1225 ** called by flush_journal_list, before it calls remove_all_from_journal_list
1226 **
1227 */
1228 static int _update_journal_header_block(struct super_block *sb,
1229                                         unsigned long offset,
1230                                         unsigned int trans_id)
1231 {
1232         struct reiserfs_journal_header *jh;
1233         struct reiserfs_journal *journal = SB_JOURNAL(sb);
1234         int depth;
1235
1236         if (reiserfs_is_journal_aborted(journal))
1237                 return -EIO;
1238
1239         if (trans_id >= journal->j_last_flush_trans_id) {
1240                 if (buffer_locked((journal->j_header_bh))) {
1241                         depth = reiserfs_write_unlock_nested(sb);
1242                         __wait_on_buffer(journal->j_header_bh);
1243                         reiserfs_write_lock_nested(sb, depth);
1244                         if (unlikely(!buffer_uptodate(journal->j_header_bh))) {
1245 #ifdef CONFIG_REISERFS_CHECK
1246                                 reiserfs_warning(sb, "journal-699",
1247                                                  "buffer write failed");
1248 #endif
1249                                 return -EIO;
1250                         }
1251                 }
1252                 journal->j_last_flush_trans_id = trans_id;
1253                 journal->j_first_unflushed_offset = offset;
1254                 jh = (struct reiserfs_journal_header *)(journal->j_header_bh->
1255                                                         b_data);
1256                 jh->j_last_flush_trans_id = cpu_to_le32(trans_id);
1257                 jh->j_first_unflushed_offset = cpu_to_le32(offset);
1258                 jh->j_mount_id = cpu_to_le32(journal->j_mount_id);
1259
1260                 set_buffer_dirty(journal->j_header_bh);
1261                 depth = reiserfs_write_unlock_nested(sb);
1262
1263                 if (reiserfs_barrier_flush(sb))
1264                         __sync_dirty_buffer(journal->j_header_bh, WRITE_FLUSH_FUA);
1265                 else
1266                         sync_dirty_buffer(journal->j_header_bh);
1267
1268                 reiserfs_write_lock_nested(sb, depth);
1269                 if (!buffer_uptodate(journal->j_header_bh)) {
1270                         reiserfs_warning(sb, "journal-837",
1271                                          "IO error during journal replay");
1272                         return -EIO;
1273                 }
1274         }
1275         return 0;
1276 }
1277
1278 static int update_journal_header_block(struct super_block *sb,
1279                                        unsigned long offset,
1280                                        unsigned int trans_id)
1281 {
1282         return _update_journal_header_block(sb, offset, trans_id);
1283 }
1284
1285 /*
1286 ** flush any and all journal lists older than you are
1287 ** can only be called from flush_journal_list
1288 */
1289 static int flush_older_journal_lists(struct super_block *sb,
1290                                      struct reiserfs_journal_list *jl)
1291 {
1292         struct list_head *entry;
1293         struct reiserfs_journal_list *other_jl;
1294         struct reiserfs_journal *journal = SB_JOURNAL(sb);
1295         unsigned int trans_id = jl->j_trans_id;
1296
1297         /* we know we are the only ones flushing things, no extra race
1298          * protection is required.
1299          */
1300       restart:
1301         entry = journal->j_journal_list.next;
1302         /* Did we wrap? */
1303         if (entry == &journal->j_journal_list)
1304                 return 0;
1305         other_jl = JOURNAL_LIST_ENTRY(entry);
1306         if (other_jl->j_trans_id < trans_id) {
1307                 BUG_ON(other_jl->j_refcount <= 0);
1308                 /* do not flush all */
1309                 flush_journal_list(sb, other_jl, 0);
1310
1311                 /* other_jl is now deleted from the list */
1312                 goto restart;
1313         }
1314         return 0;
1315 }
1316
1317 static void del_from_work_list(struct super_block *s,
1318                                struct reiserfs_journal_list *jl)
1319 {
1320         struct reiserfs_journal *journal = SB_JOURNAL(s);
1321         if (!list_empty(&jl->j_working_list)) {
1322                 list_del_init(&jl->j_working_list);
1323                 journal->j_num_work_lists--;
1324         }
1325 }
1326
1327 /* flush a journal list, both commit and real blocks
1328 **
1329 ** always set flushall to 1, unless you are calling from inside
1330 ** flush_journal_list
1331 **
1332 ** IMPORTANT.  This can only be called while there are no journal writers,
1333 ** and the journal is locked.  That means it can only be called from
1334 ** do_journal_end, or by journal_release
1335 */
1336 static int flush_journal_list(struct super_block *s,
1337                               struct reiserfs_journal_list *jl, int flushall)
1338 {
1339         struct reiserfs_journal_list *pjl;
1340         struct reiserfs_journal_cnode *cn, *last;
1341         int count;
1342         int was_jwait = 0;
1343         int was_dirty = 0;
1344         struct buffer_head *saved_bh;
1345         unsigned long j_len_saved = jl->j_len;
1346         struct reiserfs_journal *journal = SB_JOURNAL(s);
1347         int err = 0;
1348         int depth;
1349
1350         BUG_ON(j_len_saved <= 0);
1351
1352         if (atomic_read(&journal->j_wcount) != 0) {
1353                 reiserfs_warning(s, "clm-2048", "called with wcount %d",
1354                                  atomic_read(&journal->j_wcount));
1355         }
1356         BUG_ON(jl->j_trans_id == 0);
1357
1358         /* if flushall == 0, the lock is already held */
1359         if (flushall) {
1360                 reiserfs_mutex_lock_safe(&journal->j_flush_mutex, s);
1361         } else if (mutex_trylock(&journal->j_flush_mutex)) {
1362                 BUG();
1363         }
1364
1365         count = 0;
1366         if (j_len_saved > journal->j_trans_max) {
1367                 reiserfs_panic(s, "journal-715", "length is %lu, trans id %lu",
1368                                j_len_saved, jl->j_trans_id);
1369                 return 0;
1370         }
1371
1372         /* if all the work is already done, get out of here */
1373         if (atomic_read(&(jl->j_nonzerolen)) <= 0 &&
1374             atomic_read(&(jl->j_commit_left)) <= 0) {
1375                 goto flush_older_and_return;
1376         }
1377
1378         /* start by putting the commit list on disk.  This will also flush
1379          ** the commit lists of any olders transactions
1380          */
1381         flush_commit_list(s, jl, 1);
1382
1383         if (!(jl->j_state & LIST_DIRTY)
1384             && !reiserfs_is_journal_aborted(journal))
1385                 BUG();
1386
1387         /* are we done now? */
1388         if (atomic_read(&(jl->j_nonzerolen)) <= 0 &&
1389             atomic_read(&(jl->j_commit_left)) <= 0) {
1390                 goto flush_older_and_return;
1391         }
1392
1393         /* loop through each cnode, see if we need to write it,
1394          ** or wait on a more recent transaction, or just ignore it
1395          */
1396         if (atomic_read(&(journal->j_wcount)) != 0) {
1397                 reiserfs_panic(s, "journal-844", "journal list is flushing, "
1398                                "wcount is not 0");
1399         }
1400         cn = jl->j_realblock;
1401         while (cn) {
1402                 was_jwait = 0;
1403                 was_dirty = 0;
1404                 saved_bh = NULL;
1405                 /* blocknr of 0 is no longer in the hash, ignore it */
1406                 if (cn->blocknr == 0) {
1407                         goto free_cnode;
1408                 }
1409
1410                 /* This transaction failed commit. Don't write out to the disk */
1411                 if (!(jl->j_state & LIST_DIRTY))
1412                         goto free_cnode;
1413
1414                 pjl = find_newer_jl_for_cn(cn);
1415                 /* the order is important here.  We check pjl to make sure we
1416                  ** don't clear BH_JDirty_wait if we aren't the one writing this
1417                  ** block to disk
1418                  */
1419                 if (!pjl && cn->bh) {
1420                         saved_bh = cn->bh;
1421
1422                         /* we do this to make sure nobody releases the buffer while
1423                          ** we are working with it
1424                          */
1425                         get_bh(saved_bh);
1426
1427                         if (buffer_journal_dirty(saved_bh)) {
1428                                 BUG_ON(!can_dirty(cn));
1429                                 was_jwait = 1;
1430                                 was_dirty = 1;
1431                         } else if (can_dirty(cn)) {
1432                                 /* everything with !pjl && jwait should be writable */
1433                                 BUG();
1434                         }
1435                 }
1436
1437                 /* if someone has this block in a newer transaction, just make
1438                  ** sure they are committed, and don't try writing it to disk
1439                  */
1440                 if (pjl) {
1441                         if (atomic_read(&pjl->j_commit_left))
1442                                 flush_commit_list(s, pjl, 1);
1443                         goto free_cnode;
1444                 }
1445
1446                 /* bh == NULL when the block got to disk on its own, OR,
1447                  ** the block got freed in a future transaction
1448                  */
1449                 if (saved_bh == NULL) {
1450                         goto free_cnode;
1451                 }
1452
1453                 /* this should never happen.  kupdate_one_transaction has this list
1454                  ** locked while it works, so we should never see a buffer here that
1455                  ** is not marked JDirty_wait
1456                  */
1457                 if ((!was_jwait) && !buffer_locked(saved_bh)) {
1458                         reiserfs_warning(s, "journal-813",
1459                                          "BAD! buffer %llu %cdirty %cjwait, "
1460                                          "not in a newer tranasction",
1461                                          (unsigned long long)saved_bh->
1462                                          b_blocknr, was_dirty ? ' ' : '!',
1463                                          was_jwait ? ' ' : '!');
1464                 }
1465                 if (was_dirty) {
1466                         /* we inc again because saved_bh gets decremented at free_cnode */
1467                         get_bh(saved_bh);
1468                         set_bit(BLOCK_NEEDS_FLUSH, &cn->state);
1469                         lock_buffer(saved_bh);
1470                         BUG_ON(cn->blocknr != saved_bh->b_blocknr);
1471                         if (buffer_dirty(saved_bh))
1472                                 submit_logged_buffer(saved_bh);
1473                         else
1474                                 unlock_buffer(saved_bh);
1475                         count++;
1476                 } else {
1477                         reiserfs_warning(s, "clm-2082",
1478                                          "Unable to flush buffer %llu in %s",
1479                                          (unsigned long long)saved_bh->
1480                                          b_blocknr, __func__);
1481                 }
1482               free_cnode:
1483                 last = cn;
1484                 cn = cn->next;
1485                 if (saved_bh) {
1486                         /* we incremented this to keep others from taking the buffer head away */
1487                         put_bh(saved_bh);
1488                         if (atomic_read(&(saved_bh->b_count)) < 0) {
1489                                 reiserfs_warning(s, "journal-945",
1490                                                  "saved_bh->b_count < 0");
1491                         }
1492                 }
1493         }
1494         if (count > 0) {
1495                 cn = jl->j_realblock;
1496                 while (cn) {
1497                         if (test_bit(BLOCK_NEEDS_FLUSH, &cn->state)) {
1498                                 if (!cn->bh) {
1499                                         reiserfs_panic(s, "journal-1011",
1500                                                        "cn->bh is NULL");
1501                                 }
1502
1503                                 depth = reiserfs_write_unlock_nested(s);
1504                                 __wait_on_buffer(cn->bh);
1505                                 reiserfs_write_lock_nested(s, depth);
1506
1507                                 if (!cn->bh) {
1508                                         reiserfs_panic(s, "journal-1012",
1509                                                        "cn->bh is NULL");
1510                                 }
1511                                 if (unlikely(!buffer_uptodate(cn->bh))) {
1512 #ifdef CONFIG_REISERFS_CHECK
1513                                         reiserfs_warning(s, "journal-949",
1514                                                          "buffer write failed");
1515 #endif
1516                                         err = -EIO;
1517                                 }
1518                                 /* note, we must clear the JDirty_wait bit after the up to date
1519                                  ** check, otherwise we race against our flushpage routine
1520                                  */
1521                                 BUG_ON(!test_clear_buffer_journal_dirty
1522                                        (cn->bh));
1523
1524                                 /* drop one ref for us */
1525                                 put_bh(cn->bh);
1526                                 /* drop one ref for journal_mark_dirty */
1527                                 release_buffer_page(cn->bh);
1528                         }
1529                         cn = cn->next;
1530                 }
1531         }
1532
1533         if (err)
1534                 reiserfs_abort(s, -EIO,
1535                                "Write error while pushing transaction to disk in %s",
1536                                __func__);
1537       flush_older_and_return:
1538
1539         /* before we can update the journal header block, we _must_ flush all
1540          ** real blocks from all older transactions to disk.  This is because
1541          ** once the header block is updated, this transaction will not be
1542          ** replayed after a crash
1543          */
1544         if (flushall) {
1545                 flush_older_journal_lists(s, jl);
1546         }
1547
1548         err = journal->j_errno;
1549         /* before we can remove everything from the hash tables for this
1550          ** transaction, we must make sure it can never be replayed
1551          **
1552          ** since we are only called from do_journal_end, we know for sure there
1553          ** are no allocations going on while we are flushing journal lists.  So,
1554          ** we only need to update the journal header block for the last list
1555          ** being flushed
1556          */
1557         if (!err && flushall) {
1558                 err =
1559                     update_journal_header_block(s,
1560                                                 (jl->j_start + jl->j_len +
1561                                                  2) % SB_ONDISK_JOURNAL_SIZE(s),
1562                                                 jl->j_trans_id);
1563                 if (err)
1564                         reiserfs_abort(s, -EIO,
1565                                        "Write error while updating journal header in %s",
1566                                        __func__);
1567         }
1568         remove_all_from_journal_list(s, jl, 0);
1569         list_del_init(&jl->j_list);
1570         journal->j_num_lists--;
1571         del_from_work_list(s, jl);
1572
1573         if (journal->j_last_flush_id != 0 &&
1574             (jl->j_trans_id - journal->j_last_flush_id) != 1) {
1575                 reiserfs_warning(s, "clm-2201", "last flush %lu, current %lu",
1576                                  journal->j_last_flush_id, jl->j_trans_id);
1577         }
1578         journal->j_last_flush_id = jl->j_trans_id;
1579
1580         /* not strictly required since we are freeing the list, but it should
1581          * help find code using dead lists later on
1582          */
1583         jl->j_len = 0;
1584         atomic_set(&(jl->j_nonzerolen), 0);
1585         jl->j_start = 0;
1586         jl->j_realblock = NULL;
1587         jl->j_commit_bh = NULL;
1588         jl->j_trans_id = 0;
1589         jl->j_state = 0;
1590         put_journal_list(s, jl);
1591         if (flushall)
1592                 mutex_unlock(&journal->j_flush_mutex);
1593         return err;
1594 }
1595
1596 static int test_transaction(struct super_block *s,
1597                             struct reiserfs_journal_list *jl)
1598 {
1599         struct reiserfs_journal_cnode *cn;
1600
1601         if (jl->j_len == 0 || atomic_read(&jl->j_nonzerolen) == 0)
1602                 return 1;
1603
1604         cn = jl->j_realblock;
1605         while (cn) {
1606                 /* if the blocknr == 0, this has been cleared from the hash,
1607                  ** skip it
1608                  */
1609                 if (cn->blocknr == 0) {
1610                         goto next;
1611                 }
1612                 if (cn->bh && !newer_jl_done(cn))
1613                         return 0;
1614               next:
1615                 cn = cn->next;
1616                 cond_resched();
1617         }
1618         return 0;
1619 }
1620
1621 static int write_one_transaction(struct super_block *s,
1622                                  struct reiserfs_journal_list *jl,
1623                                  struct buffer_chunk *chunk)
1624 {
1625         struct reiserfs_journal_cnode *cn;
1626         int ret = 0;
1627
1628         jl->j_state |= LIST_TOUCHED;
1629         del_from_work_list(s, jl);
1630         if (jl->j_len == 0 || atomic_read(&jl->j_nonzerolen) == 0) {
1631                 return 0;
1632         }
1633
1634         cn = jl->j_realblock;
1635         while (cn) {
1636                 /* if the blocknr == 0, this has been cleared from the hash,
1637                  ** skip it
1638                  */
1639                 if (cn->blocknr == 0) {
1640                         goto next;
1641                 }
1642                 if (cn->bh && can_dirty(cn) && buffer_dirty(cn->bh)) {
1643                         struct buffer_head *tmp_bh;
1644                         /* we can race against journal_mark_freed when we try
1645                          * to lock_buffer(cn->bh), so we have to inc the buffer
1646                          * count, and recheck things after locking
1647                          */
1648                         tmp_bh = cn->bh;
1649                         get_bh(tmp_bh);
1650                         lock_buffer(tmp_bh);
1651                         if (cn->bh && can_dirty(cn) && buffer_dirty(tmp_bh)) {
1652                                 if (!buffer_journal_dirty(tmp_bh) ||
1653                                     buffer_journal_prepared(tmp_bh))
1654                                         BUG();
1655                                 add_to_chunk(chunk, tmp_bh, NULL, write_chunk);
1656                                 ret++;
1657                         } else {
1658                                 /* note, cn->bh might be null now */
1659                                 unlock_buffer(tmp_bh);
1660                         }
1661                         put_bh(tmp_bh);
1662                 }
1663               next:
1664                 cn = cn->next;
1665                 cond_resched();
1666         }
1667         return ret;
1668 }
1669
1670 /* used by flush_commit_list */
1671 static int dirty_one_transaction(struct super_block *s,
1672                                  struct reiserfs_journal_list *jl)
1673 {
1674         struct reiserfs_journal_cnode *cn;
1675         struct reiserfs_journal_list *pjl;
1676         int ret = 0;
1677
1678         jl->j_state |= LIST_DIRTY;
1679         cn = jl->j_realblock;
1680         while (cn) {
1681                 /* look for a more recent transaction that logged this
1682                  ** buffer.  Only the most recent transaction with a buffer in
1683                  ** it is allowed to send that buffer to disk
1684                  */
1685                 pjl = find_newer_jl_for_cn(cn);
1686                 if (!pjl && cn->blocknr && cn->bh
1687                     && buffer_journal_dirty(cn->bh)) {
1688                         BUG_ON(!can_dirty(cn));
1689                         /* if the buffer is prepared, it will either be logged
1690                          * or restored.  If restored, we need to make sure
1691                          * it actually gets marked dirty
1692                          */
1693                         clear_buffer_journal_new(cn->bh);
1694                         if (buffer_journal_prepared(cn->bh)) {
1695                                 set_buffer_journal_restore_dirty(cn->bh);
1696                         } else {
1697                                 set_buffer_journal_test(cn->bh);
1698                                 mark_buffer_dirty(cn->bh);
1699                         }
1700                 }
1701                 cn = cn->next;
1702         }
1703         return ret;
1704 }
1705
1706 static int kupdate_transactions(struct super_block *s,
1707                                 struct reiserfs_journal_list *jl,
1708                                 struct reiserfs_journal_list **next_jl,
1709                                 unsigned int *next_trans_id,
1710                                 int num_blocks, int num_trans)
1711 {
1712         int ret = 0;
1713         int written = 0;
1714         int transactions_flushed = 0;
1715         unsigned int orig_trans_id = jl->j_trans_id;
1716         struct buffer_chunk chunk;
1717         struct list_head *entry;
1718         struct reiserfs_journal *journal = SB_JOURNAL(s);
1719         chunk.nr = 0;
1720
1721         reiserfs_mutex_lock_safe(&journal->j_flush_mutex, s);
1722         if (!journal_list_still_alive(s, orig_trans_id)) {
1723                 goto done;
1724         }
1725
1726         /* we've got j_flush_mutex held, nobody is going to delete any
1727          * of these lists out from underneath us
1728          */
1729         while ((num_trans && transactions_flushed < num_trans) ||
1730                (!num_trans && written < num_blocks)) {
1731
1732                 if (jl->j_len == 0 || (jl->j_state & LIST_TOUCHED) ||
1733                     atomic_read(&jl->j_commit_left)
1734                     || !(jl->j_state & LIST_DIRTY)) {
1735                         del_from_work_list(s, jl);
1736                         break;
1737                 }
1738                 ret = write_one_transaction(s, jl, &chunk);
1739
1740                 if (ret < 0)
1741                         goto done;
1742                 transactions_flushed++;
1743                 written += ret;
1744                 entry = jl->j_list.next;
1745
1746                 /* did we wrap? */
1747                 if (entry == &journal->j_journal_list) {
1748                         break;
1749                 }
1750                 jl = JOURNAL_LIST_ENTRY(entry);
1751
1752                 /* don't bother with older transactions */
1753                 if (jl->j_trans_id <= orig_trans_id)
1754                         break;
1755         }
1756         if (chunk.nr) {
1757                 write_chunk(&chunk);
1758         }
1759
1760       done:
1761         mutex_unlock(&journal->j_flush_mutex);
1762         return ret;
1763 }
1764
1765 /* for o_sync and fsync heavy applications, they tend to use
1766 ** all the journa list slots with tiny transactions.  These
1767 ** trigger lots and lots of calls to update the header block, which
1768 ** adds seeks and slows things down.
1769 **
1770 ** This function tries to clear out a large chunk of the journal lists
1771 ** at once, which makes everything faster since only the newest journal
1772 ** list updates the header block
1773 */
1774 static int flush_used_journal_lists(struct super_block *s,
1775                                     struct reiserfs_journal_list *jl)
1776 {
1777         unsigned long len = 0;
1778         unsigned long cur_len;
1779         int ret;
1780         int i;
1781         int limit = 256;
1782         struct reiserfs_journal_list *tjl;
1783         struct reiserfs_journal_list *flush_jl;
1784         unsigned int trans_id;
1785         struct reiserfs_journal *journal = SB_JOURNAL(s);
1786
1787         flush_jl = tjl = jl;
1788
1789         /* in data logging mode, try harder to flush a lot of blocks */
1790         if (reiserfs_data_log(s))
1791                 limit = 1024;
1792         /* flush for 256 transactions or limit blocks, whichever comes first */
1793         for (i = 0; i < 256 && len < limit; i++) {
1794                 if (atomic_read(&tjl->j_commit_left) ||
1795                     tjl->j_trans_id < jl->j_trans_id) {
1796                         break;
1797                 }
1798                 cur_len = atomic_read(&tjl->j_nonzerolen);
1799                 if (cur_len > 0) {
1800                         tjl->j_state &= ~LIST_TOUCHED;
1801                 }
1802                 len += cur_len;
1803                 flush_jl = tjl;
1804                 if (tjl->j_list.next == &journal->j_journal_list)
1805                         break;
1806                 tjl = JOURNAL_LIST_ENTRY(tjl->j_list.next);
1807         }
1808         /* try to find a group of blocks we can flush across all the
1809          ** transactions, but only bother if we've actually spanned
1810          ** across multiple lists
1811          */
1812         if (flush_jl != jl) {
1813                 ret = kupdate_transactions(s, jl, &tjl, &trans_id, len, i);
1814         }
1815         flush_journal_list(s, flush_jl, 1);
1816         return 0;
1817 }
1818
1819 /*
1820 ** removes any nodes in table with name block and dev as bh.
1821 ** only touchs the hnext and hprev pointers.
1822 */
1823 void remove_journal_hash(struct super_block *sb,
1824                          struct reiserfs_journal_cnode **table,
1825                          struct reiserfs_journal_list *jl,
1826                          unsigned long block, int remove_freed)
1827 {
1828         struct reiserfs_journal_cnode *cur;
1829         struct reiserfs_journal_cnode **head;
1830
1831         head = &(journal_hash(table, sb, block));
1832         if (!head) {
1833                 return;
1834         }
1835         cur = *head;
1836         while (cur) {
1837                 if (cur->blocknr == block && cur->sb == sb
1838                     && (jl == NULL || jl == cur->jlist)
1839                     && (!test_bit(BLOCK_FREED, &cur->state) || remove_freed)) {
1840                         if (cur->hnext) {
1841                                 cur->hnext->hprev = cur->hprev;
1842                         }
1843                         if (cur->hprev) {
1844                                 cur->hprev->hnext = cur->hnext;
1845                         } else {
1846                                 *head = cur->hnext;
1847                         }
1848                         cur->blocknr = 0;
1849                         cur->sb = NULL;
1850                         cur->state = 0;
1851                         if (cur->bh && cur->jlist)      /* anybody who clears the cur->bh will also dec the nonzerolen */
1852                                 atomic_dec(&(cur->jlist->j_nonzerolen));
1853                         cur->bh = NULL;
1854                         cur->jlist = NULL;
1855                 }
1856                 cur = cur->hnext;
1857         }
1858 }
1859
1860 static void free_journal_ram(struct super_block *sb)
1861 {
1862         struct reiserfs_journal *journal = SB_JOURNAL(sb);
1863         kfree(journal->j_current_jl);
1864         journal->j_num_lists--;
1865
1866         vfree(journal->j_cnode_free_orig);
1867         free_list_bitmaps(sb, journal->j_list_bitmap);
1868         free_bitmap_nodes(sb);  /* must be after free_list_bitmaps */
1869         if (journal->j_header_bh) {
1870                 brelse(journal->j_header_bh);
1871         }
1872         /* j_header_bh is on the journal dev, make sure not to release the journal
1873          * dev until we brelse j_header_bh
1874          */
1875         release_journal_dev(sb, journal);
1876         vfree(journal);
1877 }
1878
1879 /*
1880 ** call on unmount.  Only set error to 1 if you haven't made your way out
1881 ** of read_super() yet.  Any other caller must keep error at 0.
1882 */
1883 static int do_journal_release(struct reiserfs_transaction_handle *th,
1884                               struct super_block *sb, int error)
1885 {
1886         struct reiserfs_transaction_handle myth;
1887         int flushed = 0;
1888         struct reiserfs_journal *journal = SB_JOURNAL(sb);
1889
1890         /* we only want to flush out transactions if we were called with error == 0
1891          */
1892         if (!error && !(sb->s_flags & MS_RDONLY)) {
1893                 /* end the current trans */
1894                 BUG_ON(!th->t_trans_id);
1895                 do_journal_end(th, sb, 10, FLUSH_ALL);
1896
1897                 /* make sure something gets logged to force our way into the flush code */
1898                 if (!journal_join(&myth, sb, 1)) {
1899                         reiserfs_prepare_for_journal(sb,
1900                                                      SB_BUFFER_WITH_SB(sb),
1901                                                      1);
1902                         journal_mark_dirty(&myth, sb,
1903                                            SB_BUFFER_WITH_SB(sb));
1904                         do_journal_end(&myth, sb, 1, FLUSH_ALL);
1905                         flushed = 1;
1906                 }
1907         }
1908
1909         /* this also catches errors during the do_journal_end above */
1910         if (!error && reiserfs_is_journal_aborted(journal)) {
1911                 memset(&myth, 0, sizeof(myth));
1912                 if (!journal_join_abort(&myth, sb, 1)) {
1913                         reiserfs_prepare_for_journal(sb,
1914                                                      SB_BUFFER_WITH_SB(sb),
1915                                                      1);
1916                         journal_mark_dirty(&myth, sb,
1917                                            SB_BUFFER_WITH_SB(sb));
1918                         do_journal_end(&myth, sb, 1, FLUSH_ALL);
1919                 }
1920         }
1921
1922         reiserfs_mounted_fs_count--;
1923         /* wait for all commits to finish */
1924         cancel_delayed_work(&SB_JOURNAL(sb)->j_work);
1925
1926         /*
1927          * We must release the write lock here because
1928          * the workqueue job (flush_async_commit) needs this lock
1929          */
1930         reiserfs_write_unlock(sb);
1931
1932         cancel_delayed_work_sync(&REISERFS_SB(sb)->old_work);
1933         flush_workqueue(commit_wq);
1934
1935         if (!reiserfs_mounted_fs_count) {
1936                 destroy_workqueue(commit_wq);
1937                 commit_wq = NULL;
1938         }
1939
1940         free_journal_ram(sb);
1941
1942         reiserfs_write_lock(sb);
1943
1944         return 0;
1945 }
1946
1947 /*
1948 ** call on unmount.  flush all journal trans, release all alloc'd ram
1949 */
1950 int journal_release(struct reiserfs_transaction_handle *th,
1951                     struct super_block *sb)
1952 {
1953         return do_journal_release(th, sb, 0);
1954 }
1955
1956 /*
1957 ** only call from an error condition inside reiserfs_read_super!
1958 */
1959 int journal_release_error(struct reiserfs_transaction_handle *th,
1960                           struct super_block *sb)
1961 {
1962         return do_journal_release(th, sb, 1);
1963 }
1964
1965 /* compares description block with commit block.  returns 1 if they differ, 0 if they are the same */
1966 static int journal_compare_desc_commit(struct super_block *sb,
1967                                        struct reiserfs_journal_desc *desc,
1968                                        struct reiserfs_journal_commit *commit)
1969 {
1970         if (get_commit_trans_id(commit) != get_desc_trans_id(desc) ||
1971             get_commit_trans_len(commit) != get_desc_trans_len(desc) ||
1972             get_commit_trans_len(commit) > SB_JOURNAL(sb)->j_trans_max ||
1973             get_commit_trans_len(commit) <= 0) {
1974                 return 1;
1975         }
1976         return 0;
1977 }
1978
1979 /* returns 0 if it did not find a description block
1980 ** returns -1 if it found a corrupt commit block
1981 ** returns 1 if both desc and commit were valid
1982 ** NOTE: only called during fs mount
1983 */
1984 static int journal_transaction_is_valid(struct super_block *sb,
1985                                         struct buffer_head *d_bh,
1986                                         unsigned int *oldest_invalid_trans_id,
1987                                         unsigned long *newest_mount_id)
1988 {
1989         struct reiserfs_journal_desc *desc;
1990         struct reiserfs_journal_commit *commit;
1991         struct buffer_head *c_bh;
1992         unsigned long offset;
1993
1994         if (!d_bh)
1995                 return 0;
1996
1997         desc = (struct reiserfs_journal_desc *)d_bh->b_data;
1998         if (get_desc_trans_len(desc) > 0
1999             && !memcmp(get_journal_desc_magic(d_bh), JOURNAL_DESC_MAGIC, 8)) {
2000                 if (oldest_invalid_trans_id && *oldest_invalid_trans_id
2001                     && get_desc_trans_id(desc) > *oldest_invalid_trans_id) {
2002                         reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2003                                        "journal-986: transaction "
2004                                        "is valid returning because trans_id %d is greater than "
2005                                        "oldest_invalid %lu",
2006                                        get_desc_trans_id(desc),
2007                                        *oldest_invalid_trans_id);
2008                         return 0;
2009                 }
2010                 if (newest_mount_id
2011                     && *newest_mount_id > get_desc_mount_id(desc)) {
2012                         reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2013                                        "journal-1087: transaction "
2014                                        "is valid returning because mount_id %d is less than "
2015                                        "newest_mount_id %lu",
2016                                        get_desc_mount_id(desc),
2017                                        *newest_mount_id);
2018                         return -1;
2019                 }
2020                 if (get_desc_trans_len(desc) > SB_JOURNAL(sb)->j_trans_max) {
2021                         reiserfs_warning(sb, "journal-2018",
2022                                          "Bad transaction length %d "
2023                                          "encountered, ignoring transaction",
2024                                          get_desc_trans_len(desc));
2025                         return -1;
2026                 }
2027                 offset = d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2028
2029                 /* ok, we have a journal description block, lets see if the transaction was valid */
2030                 c_bh =
2031                     journal_bread(sb,
2032                                   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2033                                   ((offset + get_desc_trans_len(desc) +
2034                                     1) % SB_ONDISK_JOURNAL_SIZE(sb)));
2035                 if (!c_bh)
2036                         return 0;
2037                 commit = (struct reiserfs_journal_commit *)c_bh->b_data;
2038                 if (journal_compare_desc_commit(sb, desc, commit)) {
2039                         reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2040                                        "journal_transaction_is_valid, commit offset %ld had bad "
2041                                        "time %d or length %d",
2042                                        c_bh->b_blocknr -
2043                                        SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2044                                        get_commit_trans_id(commit),
2045                                        get_commit_trans_len(commit));
2046                         brelse(c_bh);
2047                         if (oldest_invalid_trans_id) {
2048                                 *oldest_invalid_trans_id =
2049                                     get_desc_trans_id(desc);
2050                                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2051                                                "journal-1004: "
2052                                                "transaction_is_valid setting oldest invalid trans_id "
2053                                                "to %d",
2054                                                get_desc_trans_id(desc));
2055                         }
2056                         return -1;
2057                 }
2058                 brelse(c_bh);
2059                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2060                                "journal-1006: found valid "
2061                                "transaction start offset %llu, len %d id %d",
2062                                d_bh->b_blocknr -
2063                                SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2064                                get_desc_trans_len(desc),
2065                                get_desc_trans_id(desc));
2066                 return 1;
2067         } else {
2068                 return 0;
2069         }
2070 }
2071
2072 static void brelse_array(struct buffer_head **heads, int num)
2073 {
2074         int i;
2075         for (i = 0; i < num; i++) {
2076                 brelse(heads[i]);
2077         }
2078 }
2079
2080 /*
2081 ** given the start, and values for the oldest acceptable transactions,
2082 ** this either reads in a replays a transaction, or returns because the
2083 ** transaction is invalid, or too old.
2084 ** NOTE: only called during fs mount
2085 */
2086 static int journal_read_transaction(struct super_block *sb,
2087                                     unsigned long cur_dblock,
2088                                     unsigned long oldest_start,
2089                                     unsigned int oldest_trans_id,
2090                                     unsigned long newest_mount_id)
2091 {
2092         struct reiserfs_journal *journal = SB_JOURNAL(sb);
2093         struct reiserfs_journal_desc *desc;
2094         struct reiserfs_journal_commit *commit;
2095         unsigned int trans_id = 0;
2096         struct buffer_head *c_bh;
2097         struct buffer_head *d_bh;
2098         struct buffer_head **log_blocks = NULL;
2099         struct buffer_head **real_blocks = NULL;
2100         unsigned int trans_offset;
2101         int i;
2102         int trans_half;
2103
2104         d_bh = journal_bread(sb, cur_dblock);
2105         if (!d_bh)
2106                 return 1;
2107         desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2108         trans_offset = d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2109         reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1037: "
2110                        "journal_read_transaction, offset %llu, len %d mount_id %d",
2111                        d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2112                        get_desc_trans_len(desc), get_desc_mount_id(desc));
2113         if (get_desc_trans_id(desc) < oldest_trans_id) {
2114                 reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1039: "
2115                                "journal_read_trans skipping because %lu is too old",
2116                                cur_dblock -
2117                                SB_ONDISK_JOURNAL_1st_BLOCK(sb));
2118                 brelse(d_bh);
2119                 return 1;
2120         }
2121         if (get_desc_mount_id(desc) != newest_mount_id) {
2122                 reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1146: "
2123                                "journal_read_trans skipping because %d is != "
2124                                "newest_mount_id %lu", get_desc_mount_id(desc),
2125                                newest_mount_id);
2126                 brelse(d_bh);
2127                 return 1;
2128         }
2129         c_bh = journal_bread(sb, SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2130                              ((trans_offset + get_desc_trans_len(desc) + 1) %
2131                               SB_ONDISK_JOURNAL_SIZE(sb)));
2132         if (!c_bh) {
2133                 brelse(d_bh);
2134                 return 1;
2135         }
2136         commit = (struct reiserfs_journal_commit *)c_bh->b_data;
2137         if (journal_compare_desc_commit(sb, desc, commit)) {
2138                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2139                                "journal_read_transaction, "
2140                                "commit offset %llu had bad time %d or length %d",
2141                                c_bh->b_blocknr -
2142                                SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2143                                get_commit_trans_id(commit),
2144                                get_commit_trans_len(commit));
2145                 brelse(c_bh);
2146                 brelse(d_bh);
2147                 return 1;
2148         }
2149
2150         if (bdev_read_only(sb->s_bdev)) {
2151                 reiserfs_warning(sb, "clm-2076",
2152                                  "device is readonly, unable to replay log");
2153                 brelse(c_bh);
2154                 brelse(d_bh);
2155                 return -EROFS;
2156         }
2157
2158         trans_id = get_desc_trans_id(desc);
2159         /* now we know we've got a good transaction, and it was inside the valid time ranges */
2160         log_blocks = kmalloc(get_desc_trans_len(desc) *
2161                              sizeof(struct buffer_head *), GFP_NOFS);
2162         real_blocks = kmalloc(get_desc_trans_len(desc) *
2163                               sizeof(struct buffer_head *), GFP_NOFS);
2164         if (!log_blocks || !real_blocks) {
2165                 brelse(c_bh);
2166                 brelse(d_bh);
2167                 kfree(log_blocks);
2168                 kfree(real_blocks);
2169                 reiserfs_warning(sb, "journal-1169",
2170                                  "kmalloc failed, unable to mount FS");
2171                 return -1;
2172         }
2173         /* get all the buffer heads */
2174         trans_half = journal_trans_half(sb->s_blocksize);
2175         for (i = 0; i < get_desc_trans_len(desc); i++) {
2176                 log_blocks[i] =
2177                     journal_getblk(sb,
2178                                    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2179                                    (trans_offset + 1 +
2180                                     i) % SB_ONDISK_JOURNAL_SIZE(sb));
2181                 if (i < trans_half) {
2182                         real_blocks[i] =
2183                             sb_getblk(sb,
2184                                       le32_to_cpu(desc->j_realblock[i]));
2185                 } else {
2186                         real_blocks[i] =
2187                             sb_getblk(sb,
2188                                       le32_to_cpu(commit->
2189                                                   j_realblock[i - trans_half]));
2190                 }
2191                 if (real_blocks[i]->b_blocknr > SB_BLOCK_COUNT(sb)) {
2192                         reiserfs_warning(sb, "journal-1207",
2193                                          "REPLAY FAILURE fsck required! "
2194                                          "Block to replay is outside of "
2195                                          "filesystem");
2196                         goto abort_replay;
2197                 }
2198                 /* make sure we don't try to replay onto log or reserved area */
2199                 if (is_block_in_log_or_reserved_area
2200                     (sb, real_blocks[i]->b_blocknr)) {
2201                         reiserfs_warning(sb, "journal-1204",
2202                                          "REPLAY FAILURE fsck required! "
2203                                          "Trying to replay onto a log block");
2204                       abort_replay:
2205                         brelse_array(log_blocks, i);
2206                         brelse_array(real_blocks, i);
2207                         brelse(c_bh);
2208                         brelse(d_bh);
2209                         kfree(log_blocks);
2210                         kfree(real_blocks);
2211                         return -1;
2212                 }
2213         }
2214         /* read in the log blocks, memcpy to the corresponding real block */
2215         ll_rw_block(READ, get_desc_trans_len(desc), log_blocks);
2216         for (i = 0; i < get_desc_trans_len(desc); i++) {
2217
2218                 wait_on_buffer(log_blocks[i]);
2219                 if (!buffer_uptodate(log_blocks[i])) {
2220                         reiserfs_warning(sb, "journal-1212",
2221                                          "REPLAY FAILURE fsck required! "
2222                                          "buffer write failed");
2223                         brelse_array(log_blocks + i,
2224                                      get_desc_trans_len(desc) - i);
2225                         brelse_array(real_blocks, get_desc_trans_len(desc));
2226                         brelse(c_bh);
2227                         brelse(d_bh);
2228                         kfree(log_blocks);
2229                         kfree(real_blocks);
2230                         return -1;
2231                 }
2232                 memcpy(real_blocks[i]->b_data, log_blocks[i]->b_data,
2233                        real_blocks[i]->b_size);
2234                 set_buffer_uptodate(real_blocks[i]);
2235                 brelse(log_blocks[i]);
2236         }
2237         /* flush out the real blocks */
2238         for (i = 0; i < get_desc_trans_len(desc); i++) {
2239                 set_buffer_dirty(real_blocks[i]);
2240                 write_dirty_buffer(real_blocks[i], WRITE);
2241         }
2242         for (i = 0; i < get_desc_trans_len(desc); i++) {
2243                 wait_on_buffer(real_blocks[i]);
2244                 if (!buffer_uptodate(real_blocks[i])) {
2245                         reiserfs_warning(sb, "journal-1226",
2246                                          "REPLAY FAILURE, fsck required! "
2247                                          "buffer write failed");
2248                         brelse_array(real_blocks + i,
2249                                      get_desc_trans_len(desc) - i);
2250                         brelse(c_bh);
2251                         brelse(d_bh);
2252                         kfree(log_blocks);
2253                         kfree(real_blocks);
2254                         return -1;
2255                 }
2256                 brelse(real_blocks[i]);
2257         }
2258         cur_dblock =
2259             SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2260             ((trans_offset + get_desc_trans_len(desc) +
2261               2) % SB_ONDISK_JOURNAL_SIZE(sb));
2262         reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2263                        "journal-1095: setting journal " "start to offset %ld",
2264                        cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb));
2265
2266         /* init starting values for the first transaction, in case this is the last transaction to be replayed. */
2267         journal->j_start = cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2268         journal->j_last_flush_trans_id = trans_id;
2269         journal->j_trans_id = trans_id + 1;
2270         /* check for trans_id overflow */
2271         if (journal->j_trans_id == 0)
2272                 journal->j_trans_id = 10;
2273         brelse(c_bh);
2274         brelse(d_bh);
2275         kfree(log_blocks);
2276         kfree(real_blocks);
2277         return 0;
2278 }
2279
2280 /* This function reads blocks starting from block and to max_block of bufsize
2281    size (but no more than BUFNR blocks at a time). This proved to improve
2282    mounting speed on self-rebuilding raid5 arrays at least.
2283    Right now it is only used from journal code. But later we might use it
2284    from other places.
2285    Note: Do not use journal_getblk/sb_getblk functions here! */
2286 static struct buffer_head *reiserfs_breada(struct block_device *dev,
2287                                            b_blocknr_t block, int bufsize,
2288                                            b_blocknr_t max_block)
2289 {
2290         struct buffer_head *bhlist[BUFNR];
2291         unsigned int blocks = BUFNR;
2292         struct buffer_head *bh;
2293         int i, j;
2294
2295         bh = __getblk(dev, block, bufsize);
2296         if (buffer_uptodate(bh))
2297                 return (bh);
2298
2299         if (block + BUFNR > max_block) {
2300                 blocks = max_block - block;
2301         }
2302         bhlist[0] = bh;
2303         j = 1;
2304         for (i = 1; i < blocks; i++) {
2305                 bh = __getblk(dev, block + i, bufsize);
2306                 if (buffer_uptodate(bh)) {
2307                         brelse(bh);
2308                         break;
2309                 } else
2310                         bhlist[j++] = bh;
2311         }
2312         ll_rw_block(READ, j, bhlist);
2313         for (i = 1; i < j; i++)
2314                 brelse(bhlist[i]);
2315         bh = bhlist[0];
2316         wait_on_buffer(bh);
2317         if (buffer_uptodate(bh))
2318                 return bh;
2319         brelse(bh);
2320         return NULL;
2321 }
2322
2323 /*
2324 ** read and replay the log
2325 ** on a clean unmount, the journal header's next unflushed pointer will
2326 ** be to an invalid transaction.  This tests that before finding all the
2327 ** transactions in the log, which makes normal mount times fast.
2328 ** After a crash, this starts with the next unflushed transaction, and
2329 ** replays until it finds one too old, or invalid.
2330 ** On exit, it sets things up so the first transaction will work correctly.
2331 ** NOTE: only called during fs mount
2332 */
2333 static int journal_read(struct super_block *sb)
2334 {
2335         struct reiserfs_journal *journal = SB_JOURNAL(sb);
2336         struct reiserfs_journal_desc *desc;
2337         unsigned int oldest_trans_id = 0;
2338         unsigned int oldest_invalid_trans_id = 0;
2339         time_t start;
2340         unsigned long oldest_start = 0;
2341         unsigned long cur_dblock = 0;
2342         unsigned long newest_mount_id = 9;
2343         struct buffer_head *d_bh;
2344         struct reiserfs_journal_header *jh;
2345         int valid_journal_header = 0;
2346         int replay_count = 0;
2347         int continue_replay = 1;
2348         int ret;
2349         char b[BDEVNAME_SIZE];
2350
2351         cur_dblock = SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2352         reiserfs_info(sb, "checking transaction log (%s)\n",
2353                       bdevname(journal->j_dev_bd, b));
2354         start = get_seconds();
2355
2356         /* step 1, read in the journal header block.  Check the transaction it says
2357          ** is the first unflushed, and if that transaction is not valid,
2358          ** replay is done
2359          */
2360         journal->j_header_bh = journal_bread(sb,
2361                                              SB_ONDISK_JOURNAL_1st_BLOCK(sb)
2362                                              + SB_ONDISK_JOURNAL_SIZE(sb));
2363         if (!journal->j_header_bh) {
2364                 return 1;
2365         }
2366         jh = (struct reiserfs_journal_header *)(journal->j_header_bh->b_data);
2367         if (le32_to_cpu(jh->j_first_unflushed_offset) <
2368             SB_ONDISK_JOURNAL_SIZE(sb)
2369             && le32_to_cpu(jh->j_last_flush_trans_id) > 0) {
2370                 oldest_start =
2371                     SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2372                     le32_to_cpu(jh->j_first_unflushed_offset);
2373                 oldest_trans_id = le32_to_cpu(jh->j_last_flush_trans_id) + 1;
2374                 newest_mount_id = le32_to_cpu(jh->j_mount_id);
2375                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2376                                "journal-1153: found in "
2377                                "header: first_unflushed_offset %d, last_flushed_trans_id "
2378                                "%lu", le32_to_cpu(jh->j_first_unflushed_offset),
2379                                le32_to_cpu(jh->j_last_flush_trans_id));
2380                 valid_journal_header = 1;
2381
2382                 /* now, we try to read the first unflushed offset.  If it is not valid,
2383                  ** there is nothing more we can do, and it makes no sense to read
2384                  ** through the whole log.
2385                  */
2386                 d_bh =
2387                     journal_bread(sb,
2388                                   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2389                                   le32_to_cpu(jh->j_first_unflushed_offset));
2390                 ret = journal_transaction_is_valid(sb, d_bh, NULL, NULL);
2391                 if (!ret) {
2392                         continue_replay = 0;
2393                 }
2394                 brelse(d_bh);
2395                 goto start_log_replay;
2396         }
2397
2398         /* ok, there are transactions that need to be replayed.  start with the first log block, find
2399          ** all the valid transactions, and pick out the oldest.
2400          */
2401         while (continue_replay
2402                && cur_dblock <
2403                (SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2404                 SB_ONDISK_JOURNAL_SIZE(sb))) {
2405                 /* Note that it is required for blocksize of primary fs device and journal
2406                    device to be the same */
2407                 d_bh =
2408                     reiserfs_breada(journal->j_dev_bd, cur_dblock,
2409                                     sb->s_blocksize,
2410                                     SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2411                                     SB_ONDISK_JOURNAL_SIZE(sb));
2412                 ret =
2413                     journal_transaction_is_valid(sb, d_bh,
2414                                                  &oldest_invalid_trans_id,
2415                                                  &newest_mount_id);
2416                 if (ret == 1) {
2417                         desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2418                         if (oldest_start == 0) {        /* init all oldest_ values */
2419                                 oldest_trans_id = get_desc_trans_id(desc);
2420                                 oldest_start = d_bh->b_blocknr;
2421                                 newest_mount_id = get_desc_mount_id(desc);
2422                                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2423                                                "journal-1179: Setting "
2424                                                "oldest_start to offset %llu, trans_id %lu",
2425                                                oldest_start -
2426                                                SB_ONDISK_JOURNAL_1st_BLOCK
2427                                                (sb), oldest_trans_id);
2428                         } else if (oldest_trans_id > get_desc_trans_id(desc)) {
2429                                 /* one we just read was older */
2430                                 oldest_trans_id = get_desc_trans_id(desc);
2431                                 oldest_start = d_bh->b_blocknr;
2432                                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2433                                                "journal-1180: Resetting "
2434                                                "oldest_start to offset %lu, trans_id %lu",
2435                                                oldest_start -
2436                                                SB_ONDISK_JOURNAL_1st_BLOCK
2437                                                (sb), oldest_trans_id);
2438                         }
2439                         if (newest_mount_id < get_desc_mount_id(desc)) {
2440                                 newest_mount_id = get_desc_mount_id(desc);
2441                                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2442                                                "journal-1299: Setting "
2443                                                "newest_mount_id to %d",
2444                                                get_desc_mount_id(desc));
2445                         }
2446                         cur_dblock += get_desc_trans_len(desc) + 2;
2447                 } else {
2448                         cur_dblock++;
2449                 }
2450                 brelse(d_bh);
2451         }
2452
2453       start_log_replay:
2454         cur_dblock = oldest_start;
2455         if (oldest_trans_id) {
2456                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2457                                "journal-1206: Starting replay "
2458                                "from offset %llu, trans_id %lu",
2459                                cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2460                                oldest_trans_id);
2461
2462         }
2463         replay_count = 0;
2464         while (continue_replay && oldest_trans_id > 0) {
2465                 ret =
2466                     journal_read_transaction(sb, cur_dblock, oldest_start,
2467                                              oldest_trans_id, newest_mount_id);
2468                 if (ret < 0) {
2469                         return ret;
2470                 } else if (ret != 0) {
2471                         break;
2472                 }
2473                 cur_dblock =
2474                     SB_ONDISK_JOURNAL_1st_BLOCK(sb) + journal->j_start;
2475                 replay_count++;
2476                 if (cur_dblock == oldest_start)
2477                         break;
2478         }
2479
2480         if (oldest_trans_id == 0) {
2481                 reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2482                                "journal-1225: No valid " "transactions found");
2483         }
2484         /* j_start does not get set correctly if we don't replay any transactions.
2485          ** if we had a valid journal_header, set j_start to the first unflushed transaction value,
2486          ** copy the trans_id from the header
2487          */
2488         if (valid_journal_header && replay_count == 0) {
2489                 journal->j_start = le32_to_cpu(jh->j_first_unflushed_offset);
2490                 journal->j_trans_id =
2491                     le32_to_cpu(jh->j_last_flush_trans_id) + 1;
2492                 /* check for trans_id overflow */
2493                 if (journal->j_trans_id == 0)
2494                         journal->j_trans_id = 10;
2495                 journal->j_last_flush_trans_id =
2496                     le32_to_cpu(jh->j_last_flush_trans_id);
2497                 journal->j_mount_id = le32_to_cpu(jh->j_mount_id) + 1;
2498         } else {
2499                 journal->j_mount_id = newest_mount_id + 1;
2500         }
2501         reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1299: Setting "
2502                        "newest_mount_id to %lu", journal->j_mount_id);
2503         journal->j_first_unflushed_offset = journal->j_start;
2504         if (replay_count > 0) {
2505                 reiserfs_info(sb,
2506                               "replayed %d transactions in %lu seconds\n",
2507                               replay_count, get_seconds() - start);
2508         }
2509         /* needed to satisfy the locking in _update_journal_header_block */
2510         reiserfs_write_lock(sb);
2511         if (!bdev_read_only(sb->s_bdev) &&
2512             _update_journal_header_block(sb, journal->j_start,
2513                                          journal->j_last_flush_trans_id)) {
2514                 reiserfs_write_unlock(sb);
2515                 /* replay failed, caller must call free_journal_ram and abort
2516                  ** the mount
2517                  */
2518                 return -1;
2519         }
2520         reiserfs_write_unlock(sb);
2521         return 0;
2522 }
2523
2524 static struct reiserfs_journal_list *alloc_journal_list(struct super_block *s)
2525 {
2526         struct reiserfs_journal_list *jl;
2527         jl = kzalloc(sizeof(struct reiserfs_journal_list),
2528                      GFP_NOFS | __GFP_NOFAIL);
2529         INIT_LIST_HEAD(&jl->j_list);
2530         INIT_LIST_HEAD(&jl->j_working_list);
2531         INIT_LIST_HEAD(&jl->j_tail_bh_list);
2532         INIT_LIST_HEAD(&jl->j_bh_list);
2533         mutex_init(&jl->j_commit_mutex);
2534         SB_JOURNAL(s)->j_num_lists++;
2535         get_journal_list(jl);
2536         return jl;
2537 }
2538
2539 static void journal_list_init(struct super_block *sb)
2540 {
2541         SB_JOURNAL(sb)->j_current_jl = alloc_journal_list(sb);
2542 }
2543
2544 static void release_journal_dev(struct super_block *super,
2545                                struct reiserfs_journal *journal)
2546 {
2547         if (journal->j_dev_bd != NULL) {
2548                 blkdev_put(journal->j_dev_bd, journal->j_dev_mode);
2549                 journal->j_dev_bd = NULL;
2550         }
2551 }
2552
2553 static int journal_init_dev(struct super_block *super,
2554                             struct reiserfs_journal *journal,
2555                             const char *jdev_name)
2556 {
2557         int result;
2558         dev_t jdev;
2559         fmode_t blkdev_mode = FMODE_READ | FMODE_WRITE | FMODE_EXCL;
2560         char b[BDEVNAME_SIZE];
2561
2562         result = 0;
2563
2564         journal->j_dev_bd = NULL;
2565         jdev = SB_ONDISK_JOURNAL_DEVICE(super) ?
2566             new_decode_dev(SB_ONDISK_JOURNAL_DEVICE(super)) : super->s_dev;
2567
2568         if (bdev_read_only(super->s_bdev))
2569                 blkdev_mode = FMODE_READ;
2570
2571         /* there is no "jdev" option and journal is on separate device */
2572         if ((!jdev_name || !jdev_name[0])) {
2573                 if (jdev == super->s_dev)
2574                         blkdev_mode &= ~FMODE_EXCL;
2575                 journal->j_dev_bd = blkdev_get_by_dev(jdev, blkdev_mode,
2576                                                       journal);
2577                 journal->j_dev_mode = blkdev_mode;
2578                 if (IS_ERR(journal->j_dev_bd)) {
2579                         result = PTR_ERR(journal->j_dev_bd);
2580                         journal->j_dev_bd = NULL;
2581                         reiserfs_warning(super, "sh-458",
2582                                          "cannot init journal device '%s': %i",
2583                                          __bdevname(jdev, b), result);
2584                         return result;
2585                 } else if (jdev != super->s_dev)
2586                         set_blocksize(journal->j_dev_bd, super->s_blocksize);
2587
2588                 return 0;
2589         }
2590
2591         journal->j_dev_mode = blkdev_mode;
2592         journal->j_dev_bd = blkdev_get_by_path(jdev_name, blkdev_mode, journal);
2593         if (IS_ERR(journal->j_dev_bd)) {
2594                 result = PTR_ERR(journal->j_dev_bd);
2595                 journal->j_dev_bd = NULL;
2596                 reiserfs_warning(super,
2597                                  "journal_init_dev: Cannot open '%s': %i",
2598                                  jdev_name, result);
2599                 return result;
2600         }
2601
2602         set_blocksize(journal->j_dev_bd, super->s_blocksize);
2603         reiserfs_info(super,
2604                       "journal_init_dev: journal device: %s\n",
2605                       bdevname(journal->j_dev_bd, b));
2606         return 0;
2607 }
2608
2609 /**
2610  * When creating/tuning a file system user can assign some
2611  * journal params within boundaries which depend on the ratio
2612  * blocksize/standard_blocksize.
2613  *
2614  * For blocks >= standard_blocksize transaction size should
2615  * be not less then JOURNAL_TRANS_MIN_DEFAULT, and not more
2616  * then JOURNAL_TRANS_MAX_DEFAULT.
2617  *
2618  * For blocks < standard_blocksize these boundaries should be
2619  * decreased proportionally.
2620  */
2621 #define REISERFS_STANDARD_BLKSIZE (4096)
2622
2623 static int check_advise_trans_params(struct super_block *sb,
2624                                      struct reiserfs_journal *journal)
2625 {
2626         if (journal->j_trans_max) {
2627                 /* Non-default journal params.
2628                    Do sanity check for them. */
2629                 int ratio = 1;
2630                 if (sb->s_blocksize < REISERFS_STANDARD_BLKSIZE)
2631                         ratio = REISERFS_STANDARD_BLKSIZE / sb->s_blocksize;
2632
2633                 if (journal->j_trans_max > JOURNAL_TRANS_MAX_DEFAULT / ratio ||
2634                     journal->j_trans_max < JOURNAL_TRANS_MIN_DEFAULT / ratio ||
2635                     SB_ONDISK_JOURNAL_SIZE(sb) / journal->j_trans_max <
2636                     JOURNAL_MIN_RATIO) {
2637                         reiserfs_warning(sb, "sh-462",
2638                                          "bad transaction max size (%u). "
2639                                          "FSCK?", journal->j_trans_max);
2640                         return 1;
2641                 }
2642                 if (journal->j_max_batch != (journal->j_trans_max) *
2643                         JOURNAL_MAX_BATCH_DEFAULT/JOURNAL_TRANS_MAX_DEFAULT) {
2644                         reiserfs_warning(sb, "sh-463",
2645                                          "bad transaction max batch (%u). "
2646                                          "FSCK?", journal->j_max_batch);
2647                         return 1;
2648                 }
2649         } else {
2650                 /* Default journal params.
2651                    The file system was created by old version
2652                    of mkreiserfs, so some fields contain zeros,
2653                    and we need to advise proper values for them */
2654                 if (sb->s_blocksize != REISERFS_STANDARD_BLKSIZE) {
2655                         reiserfs_warning(sb, "sh-464", "bad blocksize (%u)",
2656                                          sb->s_blocksize);
2657                         return 1;
2658                 }
2659                 journal->j_trans_max = JOURNAL_TRANS_MAX_DEFAULT;
2660                 journal->j_max_batch = JOURNAL_MAX_BATCH_DEFAULT;
2661                 journal->j_max_commit_age = JOURNAL_MAX_COMMIT_AGE;
2662         }
2663         return 0;
2664 }
2665
2666 /*
2667 ** must be called once on fs mount.  calls journal_read for you
2668 */
2669 int journal_init(struct super_block *sb, const char *j_dev_name,
2670                  int old_format, unsigned int commit_max_age)
2671 {
2672         int num_cnodes = SB_ONDISK_JOURNAL_SIZE(sb) * 2;
2673         struct buffer_head *bhjh;
2674         struct reiserfs_super_block *rs;
2675         struct reiserfs_journal_header *jh;
2676         struct reiserfs_journal *journal;
2677         struct reiserfs_journal_list *jl;
2678         char b[BDEVNAME_SIZE];
2679         int ret;
2680
2681         journal = SB_JOURNAL(sb) = vzalloc(sizeof(struct reiserfs_journal));
2682         if (!journal) {
2683                 reiserfs_warning(sb, "journal-1256",
2684                                  "unable to get memory for journal structure");
2685                 return 1;
2686         }
2687         INIT_LIST_HEAD(&journal->j_bitmap_nodes);
2688         INIT_LIST_HEAD(&journal->j_prealloc_list);
2689         INIT_LIST_HEAD(&journal->j_working_list);
2690         INIT_LIST_HEAD(&journal->j_journal_list);
2691         journal->j_persistent_trans = 0;
2692         if (reiserfs_allocate_list_bitmaps(sb, journal->j_list_bitmap,
2693                                            reiserfs_bmap_count(sb)))
2694                 goto free_and_return;
2695
2696         allocate_bitmap_nodes(sb);
2697
2698         /* reserved for journal area support */
2699         SB_JOURNAL_1st_RESERVED_BLOCK(sb) = (old_format ?
2700                                                  REISERFS_OLD_DISK_OFFSET_IN_BYTES
2701                                                  / sb->s_blocksize +
2702                                                  reiserfs_bmap_count(sb) +
2703                                                  1 :
2704                                                  REISERFS_DISK_OFFSET_IN_BYTES /
2705                                                  sb->s_blocksize + 2);
2706
2707         /* Sanity check to see is the standard journal fitting within first bitmap
2708            (actual for small blocksizes) */
2709         if (!SB_ONDISK_JOURNAL_DEVICE(sb) &&
2710             (SB_JOURNAL_1st_RESERVED_BLOCK(sb) +
2711              SB_ONDISK_JOURNAL_SIZE(sb) > sb->s_blocksize * 8)) {
2712                 reiserfs_warning(sb, "journal-1393",
2713                                  "journal does not fit for area addressed "
2714                                  "by first of bitmap blocks. It starts at "
2715                                  "%u and its size is %u. Block size %ld",
2716                                  SB_JOURNAL_1st_RESERVED_BLOCK(sb),
2717                                  SB_ONDISK_JOURNAL_SIZE(sb),
2718                                  sb->s_blocksize);
2719                 goto free_and_return;
2720         }
2721
2722         if (journal_init_dev(sb, journal, j_dev_name) != 0) {
2723                 reiserfs_warning(sb, "sh-462",
2724                                  "unable to initialize jornal device");
2725                 goto free_and_return;
2726         }
2727
2728         rs = SB_DISK_SUPER_BLOCK(sb);
2729
2730         /* read journal header */
2731         bhjh = journal_bread(sb,
2732                              SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2733                              SB_ONDISK_JOURNAL_SIZE(sb));
2734         if (!bhjh) {
2735                 reiserfs_warning(sb, "sh-459",
2736                                  "unable to read journal header");
2737                 goto free_and_return;
2738         }
2739         jh = (struct reiserfs_journal_header *)(bhjh->b_data);
2740
2741         /* make sure that journal matches to the super block */
2742         if (is_reiserfs_jr(rs)
2743             && (le32_to_cpu(jh->jh_journal.jp_journal_magic) !=
2744                 sb_jp_journal_magic(rs))) {
2745                 reiserfs_warning(sb, "sh-460",
2746                                  "journal header magic %x (device %s) does "
2747                                  "not match to magic found in super block %x",
2748                                  jh->jh_journal.jp_journal_magic,
2749                                  bdevname(journal->j_dev_bd, b),
2750                                  sb_jp_journal_magic(rs));
2751                 brelse(bhjh);
2752                 goto free_and_return;
2753         }
2754
2755         journal->j_trans_max = le32_to_cpu(jh->jh_journal.jp_journal_trans_max);
2756         journal->j_max_batch = le32_to_cpu(jh->jh_journal.jp_journal_max_batch);
2757         journal->j_max_commit_age =
2758             le32_to_cpu(jh->jh_journal.jp_journal_max_commit_age);
2759         journal->j_max_trans_age = JOURNAL_MAX_TRANS_AGE;
2760
2761         if (check_advise_trans_params(sb, journal) != 0)
2762                 goto free_and_return;
2763         journal->j_default_max_commit_age = journal->j_max_commit_age;
2764
2765         if (commit_max_age != 0) {
2766                 journal->j_max_commit_age = commit_max_age;
2767                 journal->j_max_trans_age = commit_max_age;
2768         }
2769
2770         reiserfs_info(sb, "journal params: device %s, size %u, "
2771                       "journal first block %u, max trans len %u, max batch %u, "
2772                       "max commit age %u, max trans age %u\n",
2773                       bdevname(journal->j_dev_bd, b),
2774                       SB_ONDISK_JOURNAL_SIZE(sb),
2775                       SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2776                       journal->j_trans_max,
2777                       journal->j_max_batch,
2778                       journal->j_max_commit_age, journal->j_max_trans_age);
2779
2780         brelse(bhjh);
2781
2782         journal->j_list_bitmap_index = 0;
2783         journal_list_init(sb);
2784
2785         memset(journal->j_list_hash_table, 0,
2786                JOURNAL_HASH_SIZE * sizeof(struct reiserfs_journal_cnode *));
2787
2788         INIT_LIST_HEAD(&journal->j_dirty_buffers);
2789         spin_lock_init(&journal->j_dirty_buffers_lock);
2790
2791         journal->j_start = 0;
2792         journal->j_len = 0;
2793         journal->j_len_alloc = 0;
2794         atomic_set(&(journal->j_wcount), 0);
2795         atomic_set(&(journal->j_async_throttle), 0);
2796         journal->j_bcount = 0;
2797         journal->j_trans_start_time = 0;
2798         journal->j_last = NULL;
2799         journal->j_first = NULL;
2800         init_waitqueue_head(&(journal->j_join_wait));
2801         mutex_init(&journal->j_mutex);
2802         mutex_init(&journal->j_flush_mutex);
2803
2804         journal->j_trans_id = 10;
2805         journal->j_mount_id = 10;
2806         journal->j_state = 0;
2807         atomic_set(&(journal->j_jlock), 0);
2808         journal->j_cnode_free_list = allocate_cnodes(num_cnodes);
2809         journal->j_cnode_free_orig = journal->j_cnode_free_list;
2810         journal->j_cnode_free = journal->j_cnode_free_list ? num_cnodes : 0;
2811         journal->j_cnode_used = 0;
2812         journal->j_must_wait = 0;
2813
2814         if (journal->j_cnode_free == 0) {
2815                 reiserfs_warning(sb, "journal-2004", "Journal cnode memory "
2816                                  "allocation failed (%ld bytes). Journal is "
2817                                  "too large for available memory. Usually "
2818                                  "this is due to a journal that is too large.",
2819                                  sizeof (struct reiserfs_journal_cnode) * num_cnodes);
2820                 goto free_and_return;
2821         }
2822
2823         init_journal_hash(sb);
2824         jl = journal->j_current_jl;
2825
2826         /*
2827          * get_list_bitmap() may call flush_commit_list() which
2828          * requires the lock. Calling flush_commit_list() shouldn't happen
2829          * this early but I like to be paranoid.
2830          */
2831         reiserfs_write_lock(sb);
2832         jl->j_list_bitmap = get_list_bitmap(sb, jl);
2833         reiserfs_write_unlock(sb);
2834         if (!jl->j_list_bitmap) {
2835                 reiserfs_warning(sb, "journal-2005",
2836                                  "get_list_bitmap failed for journal list 0");
2837                 goto free_and_return;
2838         }
2839
2840         ret = journal_read(sb);
2841         if (ret < 0) {
2842                 reiserfs_warning(sb, "reiserfs-2006",
2843                                  "Replay Failure, unable to mount");
2844                 goto free_and_return;
2845         }
2846
2847         reiserfs_mounted_fs_count++;
2848         if (reiserfs_mounted_fs_count <= 1)
2849                 commit_wq = alloc_workqueue("reiserfs", WQ_MEM_RECLAIM, 0);
2850
2851         INIT_DELAYED_WORK(&journal->j_work, flush_async_commits);
2852         journal->j_work_sb = sb;
2853         return 0;
2854       free_and_return:
2855         free_journal_ram(sb);
2856         return 1;
2857 }
2858
2859 /*
2860 ** test for a polite end of the current transaction.  Used by file_write, and should
2861 ** be used by delete to make sure they don't write more than can fit inside a single
2862 ** transaction
2863 */
2864 int journal_transaction_should_end(struct reiserfs_transaction_handle *th,
2865                                    int new_alloc)
2866 {
2867         struct reiserfs_journal *journal = SB_JOURNAL(th->t_super);
2868         time_t now = get_seconds();
2869         /* cannot restart while nested */
2870         BUG_ON(!th->t_trans_id);
2871         if (th->t_refcount > 1)
2872                 return 0;
2873         if (journal->j_must_wait > 0 ||
2874             (journal->j_len_alloc + new_alloc) >= journal->j_max_batch ||
2875             atomic_read(&(journal->j_jlock)) ||
2876             (now - journal->j_trans_start_time) > journal->j_max_trans_age ||
2877             journal->j_cnode_free < (journal->j_trans_max * 3)) {
2878                 return 1;
2879         }
2880
2881         journal->j_len_alloc += new_alloc;
2882         th->t_blocks_allocated += new_alloc ;
2883         return 0;
2884 }
2885
2886 /* this must be called inside a transaction
2887 */
2888 void reiserfs_block_writes(struct reiserfs_transaction_handle *th)
2889 {
2890         struct reiserfs_journal *journal = SB_JOURNAL(th->t_super);
2891         BUG_ON(!th->t_trans_id);
2892         journal->j_must_wait = 1;
2893         set_bit(J_WRITERS_BLOCKED, &journal->j_state);
2894         return;
2895 }
2896
2897 /* this must be called without a transaction started
2898 */
2899 void reiserfs_allow_writes(struct super_block *s)
2900 {
2901         struct reiserfs_journal *journal = SB_JOURNAL(s);
2902         clear_bit(J_WRITERS_BLOCKED, &journal->j_state);
2903         wake_up(&journal->j_join_wait);
2904 }
2905
2906 /* this must be called without a transaction started
2907 */
2908 void reiserfs_wait_on_write_block(struct super_block *s)
2909 {
2910         struct reiserfs_journal *journal = SB_JOURNAL(s);
2911         wait_event(journal->j_join_wait,
2912                    !test_bit(J_WRITERS_BLOCKED, &journal->j_state));
2913 }
2914
2915 static void queue_log_writer(struct super_block *s)
2916 {
2917         wait_queue_t wait;
2918         struct reiserfs_journal *journal = SB_JOURNAL(s);
2919         set_bit(J_WRITERS_QUEUED, &journal->j_state);
2920
2921         /*
2922          * we don't want to use wait_event here because
2923          * we only want to wait once.
2924          */
2925         init_waitqueue_entry(&wait, current);
2926         add_wait_queue(&journal->j_join_wait, &wait);
2927         set_current_state(TASK_UNINTERRUPTIBLE);
2928         if (test_bit(J_WRITERS_QUEUED, &journal->j_state)) {
2929                 int depth = reiserfs_write_unlock_nested(s);
2930                 schedule();
2931                 reiserfs_write_lock_nested(s, depth);
2932         }
2933         __set_current_state(TASK_RUNNING);
2934         remove_wait_queue(&journal->j_join_wait, &wait);
2935 }
2936
2937 static void wake_queued_writers(struct super_block *s)
2938 {
2939         struct reiserfs_journal *journal = SB_JOURNAL(s);
2940         if (test_and_clear_bit(J_WRITERS_QUEUED, &journal->j_state))
2941                 wake_up(&journal->j_join_wait);
2942 }
2943
2944 static void let_transaction_grow(struct super_block *sb, unsigned int trans_id)
2945 {
2946         struct reiserfs_journal *journal = SB_JOURNAL(sb);
2947         unsigned long bcount = journal->j_bcount;
2948         while (1) {
2949                 int depth;
2950
2951                 depth = reiserfs_write_unlock_nested(sb);
2952                 schedule_timeout_uninterruptible(1);
2953                 reiserfs_write_lock_nested(sb, depth);
2954
2955                 journal->j_current_jl->j_state |= LIST_COMMIT_PENDING;
2956                 while ((atomic_read(&journal->j_wcount) > 0 ||
2957                         atomic_read(&journal->j_jlock)) &&
2958                        journal->j_trans_id == trans_id) {
2959                         queue_log_writer(sb);
2960                 }
2961                 if (journal->j_trans_id != trans_id)
2962                         break;
2963                 if (bcount == journal->j_bcount)
2964                         break;
2965                 bcount = journal->j_bcount;
2966         }
2967 }
2968
2969 /* join == true if you must join an existing transaction.
2970 ** join == false if you can deal with waiting for others to finish
2971 **
2972 ** this will block until the transaction is joinable.  send the number of blocks you
2973 ** expect to use in nblocks.
2974 */
2975 static int do_journal_begin_r(struct reiserfs_transaction_handle *th,
2976                               struct super_block *sb, unsigned long nblocks,
2977                               int join)
2978 {
2979         time_t now = get_seconds();
2980         unsigned int old_trans_id;
2981         struct reiserfs_journal *journal = SB_JOURNAL(sb);
2982         struct reiserfs_transaction_handle myth;
2983         int sched_count = 0;
2984         int retval;
2985         int depth;
2986
2987         reiserfs_check_lock_depth(sb, "journal_begin");
2988         BUG_ON(nblocks > journal->j_trans_max);
2989
2990         PROC_INFO_INC(sb, journal.journal_being);
2991         /* set here for journal_join */
2992         th->t_refcount = 1;
2993         th->t_super = sb;
2994
2995       relock:
2996         lock_journal(sb);
2997         if (join != JBEGIN_ABORT && reiserfs_is_journal_aborted(journal)) {
2998                 unlock_journal(sb);
2999                 retval = journal->j_errno;
3000                 goto out_fail;
3001         }
3002         journal->j_bcount++;
3003
3004         if (test_bit(J_WRITERS_BLOCKED, &journal->j_state)) {
3005                 unlock_journal(sb);
3006                 depth = reiserfs_write_unlock_nested(sb);
3007                 reiserfs_wait_on_write_block(sb);
3008                 reiserfs_write_lock_nested(sb, depth);
3009                 PROC_INFO_INC(sb, journal.journal_relock_writers);
3010                 goto relock;
3011         }
3012         now = get_seconds();
3013
3014         /* if there is no room in the journal OR
3015          ** if this transaction is too old, and we weren't called joinable, wait for it to finish before beginning
3016          ** we don't sleep if there aren't other writers
3017          */
3018
3019         if ((!join && journal->j_must_wait > 0) ||
3020             (!join
3021              && (journal->j_len_alloc + nblocks + 2) >= journal->j_max_batch)
3022             || (!join && atomic_read(&journal->j_wcount) > 0
3023                 && journal->j_trans_start_time > 0
3024                 && (now - journal->j_trans_start_time) >
3025                 journal->j_max_trans_age) || (!join
3026                                               && atomic_read(&journal->j_jlock))
3027             || (!join && journal->j_cnode_free < (journal->j_trans_max * 3))) {
3028
3029                 old_trans_id = journal->j_trans_id;
3030                 unlock_journal(sb);     /* allow others to finish this transaction */
3031
3032                 if (!join && (journal->j_len_alloc + nblocks + 2) >=
3033                     journal->j_max_batch &&
3034                     ((journal->j_len + nblocks + 2) * 100) <
3035                     (journal->j_len_alloc * 75)) {
3036                         if (atomic_read(&journal->j_wcount) > 10) {
3037                                 sched_count++;
3038                                 queue_log_writer(sb);
3039                                 goto relock;
3040                         }
3041                 }
3042                 /* don't mess with joining the transaction if all we have to do is
3043                  * wait for someone else to do a commit
3044                  */
3045                 if (atomic_read(&journal->j_jlock)) {
3046                         while (journal->j_trans_id == old_trans_id &&
3047                                atomic_read(&journal->j_jlock)) {
3048                                 queue_log_writer(sb);
3049                         }
3050                         goto relock;
3051                 }
3052                 retval = journal_join(&myth, sb, 1);
3053                 if (retval)
3054                         goto out_fail;
3055
3056                 /* someone might have ended the transaction while we joined */
3057                 if (old_trans_id != journal->j_trans_id) {
3058                         retval = do_journal_end(&myth, sb, 1, 0);
3059                 } else {
3060                         retval = do_journal_end(&myth, sb, 1, COMMIT_NOW);
3061                 }
3062
3063                 if (retval)
3064                         goto out_fail;
3065
3066                 PROC_INFO_INC(sb, journal.journal_relock_wcount);
3067                 goto relock;
3068         }
3069         /* we are the first writer, set trans_id */
3070         if (journal->j_trans_start_time == 0) {
3071                 journal->j_trans_start_time = get_seconds();
3072         }
3073         atomic_inc(&(journal->j_wcount));
3074         journal->j_len_alloc += nblocks;
3075         th->t_blocks_logged = 0;
3076         th->t_blocks_allocated = nblocks;
3077         th->t_trans_id = journal->j_trans_id;
3078         unlock_journal(sb);
3079         INIT_LIST_HEAD(&th->t_list);
3080         return 0;
3081
3082       out_fail:
3083         memset(th, 0, sizeof(*th));
3084         /* Re-set th->t_super, so we can properly keep track of how many
3085          * persistent transactions there are. We need to do this so if this
3086          * call is part of a failed restart_transaction, we can free it later */
3087         th->t_super = sb;
3088         return retval;
3089 }
3090
3091 struct reiserfs_transaction_handle *reiserfs_persistent_transaction(struct
3092                                                                     super_block
3093                                                                     *s,
3094                                                                     int nblocks)
3095 {
3096         int ret;
3097         struct reiserfs_transaction_handle *th;
3098
3099         /* if we're nesting into an existing transaction.  It will be
3100          ** persistent on its own
3101          */
3102         if (reiserfs_transaction_running(s)) {
3103                 th = current->journal_info;
3104                 th->t_refcount++;
3105                 BUG_ON(th->t_refcount < 2);
3106                 
3107                 return th;
3108         }
3109         th = kmalloc(sizeof(struct reiserfs_transaction_handle), GFP_NOFS);
3110         if (!th)
3111                 return NULL;
3112         ret = journal_begin(th, s, nblocks);
3113         if (ret) {
3114                 kfree(th);
3115                 return NULL;
3116         }
3117
3118         SB_JOURNAL(s)->j_persistent_trans++;
3119         return th;
3120 }
3121
3122 int reiserfs_end_persistent_transaction(struct reiserfs_transaction_handle *th)
3123 {
3124         struct super_block *s = th->t_super;
3125         int ret = 0;
3126         if (th->t_trans_id)
3127                 ret = journal_end(th, th->t_super, th->t_blocks_allocated);
3128         else
3129                 ret = -EIO;
3130         if (th->t_refcount == 0) {
3131                 SB_JOURNAL(s)->j_persistent_trans--;
3132                 kfree(th);
3133         }
3134         return ret;
3135 }
3136
3137 static int journal_join(struct reiserfs_transaction_handle *th,
3138                         struct super_block *sb, unsigned long nblocks)
3139 {
3140         struct reiserfs_transaction_handle *cur_th = current->journal_info;
3141
3142         /* this keeps do_journal_end from NULLing out the current->journal_info
3143          ** pointer
3144          */
3145         th->t_handle_save = cur_th;
3146         BUG_ON(cur_th && cur_th->t_refcount > 1);
3147         return do_journal_begin_r(th, sb, nblocks, JBEGIN_JOIN);
3148 }
3149
3150 int journal_join_abort(struct reiserfs_transaction_handle *th,
3151                        struct super_block *sb, unsigned long nblocks)
3152 {
3153         struct reiserfs_transaction_handle *cur_th = current->journal_info;
3154
3155         /* this keeps do_journal_end from NULLing out the current->journal_info
3156          ** pointer
3157          */
3158         th->t_handle_save = cur_th;
3159         BUG_ON(cur_th && cur_th->t_refcount > 1);
3160         return do_journal_begin_r(th, sb, nblocks, JBEGIN_ABORT);
3161 }
3162
3163 int journal_begin(struct reiserfs_transaction_handle *th,
3164                   struct super_block *sb, unsigned long nblocks)
3165 {
3166         struct reiserfs_transaction_handle *cur_th = current->journal_info;
3167         int ret;
3168
3169         th->t_handle_save = NULL;
3170         if (cur_th) {
3171                 /* we are nesting into the current transaction */
3172                 if (cur_th->t_super == sb) {
3173                         BUG_ON(!cur_th->t_refcount);
3174                         cur_th->t_refcount++;
3175                         memcpy(th, cur_th, sizeof(*th));
3176                         if (th->t_refcount <= 1)
3177                                 reiserfs_warning(sb, "reiserfs-2005",
3178                                                  "BAD: refcount <= 1, but "
3179                                                  "journal_info != 0");
3180                         return 0;
3181                 } else {
3182                         /* we've ended up with a handle from a different filesystem.
3183                          ** save it and restore on journal_end.  This should never
3184                          ** really happen...
3185                          */
3186                         reiserfs_warning(sb, "clm-2100",
3187                                          "nesting info a different FS");
3188                         th->t_handle_save = current->journal_info;
3189                         current->journal_info = th;
3190                 }
3191         } else {
3192                 current->journal_info = th;
3193         }
3194         ret = do_journal_begin_r(th, sb, nblocks, JBEGIN_REG);
3195         BUG_ON(current->journal_info != th);
3196
3197         /* I guess this boils down to being the reciprocal of clm-2100 above.
3198          * If do_journal_begin_r fails, we need to put it back, since journal_end
3199          * won't be called to do it. */
3200         if (ret)
3201                 current->journal_info = th->t_handle_save;
3202         else
3203                 BUG_ON(!th->t_refcount);
3204
3205         return ret;
3206 }
3207
3208 /*
3209 ** puts bh into the current transaction.  If it was already there, reorders removes the
3210 ** old pointers from the hash, and puts new ones in (to make sure replay happen in the right order).
3211 **
3212 ** if it was dirty, cleans and files onto the clean list.  I can't let it be dirty again until the
3213 ** transaction is committed.
3214 **
3215 ** if j_len, is bigger than j_len_alloc, it pushes j_len_alloc to 10 + j_len.
3216 */
3217 int journal_mark_dirty(struct reiserfs_transaction_handle *th,
3218                        struct super_block *sb, struct buffer_head *bh)
3219 {
3220         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3221         struct reiserfs_journal_cnode *cn = NULL;
3222         int count_already_incd = 0;
3223         int prepared = 0;
3224         BUG_ON(!th->t_trans_id);
3225
3226         PROC_INFO_INC(sb, journal.mark_dirty);
3227         if (th->t_trans_id != journal->j_trans_id) {
3228                 reiserfs_panic(th->t_super, "journal-1577",
3229                                "handle trans id %ld != current trans id %ld",
3230                                th->t_trans_id, journal->j_trans_id);
3231         }
3232
3233         prepared = test_clear_buffer_journal_prepared(bh);
3234         clear_buffer_journal_restore_dirty(bh);
3235         /* already in this transaction, we are done */
3236         if (buffer_journaled(bh)) {
3237                 PROC_INFO_INC(sb, journal.mark_dirty_already);
3238                 return 0;
3239         }
3240
3241         /* this must be turned into a panic instead of a warning.  We can't allow
3242          ** a dirty or journal_dirty or locked buffer to be logged, as some changes
3243          ** could get to disk too early.  NOT GOOD.
3244          */
3245         if (!prepared || buffer_dirty(bh)) {
3246                 reiserfs_warning(sb, "journal-1777",
3247                                  "buffer %llu bad state "
3248                                  "%cPREPARED %cLOCKED %cDIRTY %cJDIRTY_WAIT",
3249                                  (unsigned long long)bh->b_blocknr,
3250                                  prepared ? ' ' : '!',
3251                                  buffer_locked(bh) ? ' ' : '!',
3252                                  buffer_dirty(bh) ? ' ' : '!',
3253                                  buffer_journal_dirty(bh) ? ' ' : '!');
3254         }
3255
3256         if (atomic_read(&(journal->j_wcount)) <= 0) {
3257                 reiserfs_warning(sb, "journal-1409",
3258                                  "returning because j_wcount was %d",
3259                                  atomic_read(&(journal->j_wcount)));
3260                 return 1;
3261         }
3262         /* this error means I've screwed up, and we've overflowed the transaction.
3263          ** Nothing can be done here, except make the FS readonly or panic.
3264          */
3265         if (journal->j_len >= journal->j_trans_max) {
3266                 reiserfs_panic(th->t_super, "journal-1413",
3267                                "j_len (%lu) is too big",
3268                                journal->j_len);
3269         }
3270
3271         if (buffer_journal_dirty(bh)) {
3272                 count_already_incd = 1;
3273                 PROC_INFO_INC(sb, journal.mark_dirty_notjournal);
3274                 clear_buffer_journal_dirty(bh);
3275         }
3276
3277         if (journal->j_len > journal->j_len_alloc) {
3278                 journal->j_len_alloc = journal->j_len + JOURNAL_PER_BALANCE_CNT;
3279         }
3280
3281         set_buffer_journaled(bh);
3282
3283         /* now put this guy on the end */
3284         if (!cn) {
3285                 cn = get_cnode(sb);
3286                 if (!cn) {
3287                         reiserfs_panic(sb, "journal-4", "get_cnode failed!");
3288                 }
3289
3290                 if (th->t_blocks_logged == th->t_blocks_allocated) {
3291                         th->t_blocks_allocated += JOURNAL_PER_BALANCE_CNT;
3292                         journal->j_len_alloc += JOURNAL_PER_BALANCE_CNT;
3293                 }
3294                 th->t_blocks_logged++;
3295                 journal->j_len++;
3296
3297                 cn->bh = bh;
3298                 cn->blocknr = bh->b_blocknr;
3299                 cn->sb = sb;
3300                 cn->jlist = NULL;
3301                 insert_journal_hash(journal->j_hash_table, cn);
3302                 if (!count_already_incd) {
3303                         get_bh(bh);
3304                 }
3305         }
3306         cn->next = NULL;
3307         cn->prev = journal->j_last;
3308         cn->bh = bh;
3309         if (journal->j_last) {
3310                 journal->j_last->next = cn;
3311                 journal->j_last = cn;
3312         } else {
3313                 journal->j_first = cn;
3314                 journal->j_last = cn;
3315         }
3316         reiserfs_schedule_old_flush(sb);
3317         return 0;
3318 }
3319
3320 int journal_end(struct reiserfs_transaction_handle *th,
3321                 struct super_block *sb, unsigned long nblocks)
3322 {
3323         if (!current->journal_info && th->t_refcount > 1)
3324                 reiserfs_warning(sb, "REISER-NESTING",
3325                                  "th NULL, refcount %d", th->t_refcount);
3326
3327         if (!th->t_trans_id) {
3328                 WARN_ON(1);
3329                 return -EIO;
3330         }
3331
3332         th->t_refcount--;
3333         if (th->t_refcount > 0) {
3334                 struct reiserfs_transaction_handle *cur_th =
3335                     current->journal_info;
3336
3337                 /* we aren't allowed to close a nested transaction on a different
3338                  ** filesystem from the one in the task struct
3339                  */
3340                 BUG_ON(cur_th->t_super != th->t_super);
3341
3342                 if (th != cur_th) {
3343                         memcpy(current->journal_info, th, sizeof(*th));
3344                         th->t_trans_id = 0;
3345                 }
3346                 return 0;
3347         } else {
3348                 return do_journal_end(th, sb, nblocks, 0);
3349         }
3350 }
3351
3352 /* removes from the current transaction, relsing and descrementing any counters.
3353 ** also files the removed buffer directly onto the clean list
3354 **
3355 ** called by journal_mark_freed when a block has been deleted
3356 **
3357 ** returns 1 if it cleaned and relsed the buffer. 0 otherwise
3358 */
3359 static int remove_from_transaction(struct super_block *sb,
3360                                    b_blocknr_t blocknr, int already_cleaned)
3361 {
3362         struct buffer_head *bh;
3363         struct reiserfs_journal_cnode *cn;
3364         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3365         int ret = 0;
3366
3367         cn = get_journal_hash_dev(sb, journal->j_hash_table, blocknr);
3368         if (!cn || !cn->bh) {
3369                 return ret;
3370         }
3371         bh = cn->bh;
3372         if (cn->prev) {
3373                 cn->prev->next = cn->next;
3374         }
3375         if (cn->next) {
3376                 cn->next->prev = cn->prev;
3377         }
3378         if (cn == journal->j_first) {
3379                 journal->j_first = cn->next;
3380         }
3381         if (cn == journal->j_last) {
3382                 journal->j_last = cn->prev;
3383         }
3384         if (bh)
3385                 remove_journal_hash(sb, journal->j_hash_table, NULL,
3386                                     bh->b_blocknr, 0);
3387         clear_buffer_journaled(bh);     /* don't log this one */
3388
3389         if (!already_cleaned) {
3390                 clear_buffer_journal_dirty(bh);
3391                 clear_buffer_dirty(bh);
3392                 clear_buffer_journal_test(bh);
3393                 put_bh(bh);
3394                 if (atomic_read(&(bh->b_count)) < 0) {
3395                         reiserfs_warning(sb, "journal-1752",
3396                                          "b_count < 0");
3397                 }
3398                 ret = 1;
3399         }
3400         journal->j_len--;
3401         journal->j_len_alloc--;
3402         free_cnode(sb, cn);
3403         return ret;
3404 }
3405
3406 /*
3407 ** for any cnode in a journal list, it can only be dirtied of all the
3408 ** transactions that include it are committed to disk.
3409 ** this checks through each transaction, and returns 1 if you are allowed to dirty,
3410 ** and 0 if you aren't
3411 **
3412 ** it is called by dirty_journal_list, which is called after flush_commit_list has gotten all the log
3413 ** blocks for a given transaction on disk
3414 **
3415 */
3416 static int can_dirty(struct reiserfs_journal_cnode *cn)
3417 {
3418         struct super_block *sb = cn->sb;
3419         b_blocknr_t blocknr = cn->blocknr;
3420         struct reiserfs_journal_cnode *cur = cn->hprev;
3421         int can_dirty = 1;
3422
3423         /* first test hprev.  These are all newer than cn, so any node here
3424          ** with the same block number and dev means this node can't be sent
3425          ** to disk right now.
3426          */
3427         while (cur && can_dirty) {
3428                 if (cur->jlist && cur->bh && cur->blocknr && cur->sb == sb &&
3429                     cur->blocknr == blocknr) {
3430                         can_dirty = 0;
3431                 }
3432                 cur = cur->hprev;
3433         }
3434         /* then test hnext.  These are all older than cn.  As long as they
3435          ** are committed to the log, it is safe to write cn to disk
3436          */
3437         cur = cn->hnext;
3438         while (cur && can_dirty) {
3439                 if (cur->jlist && cur->jlist->j_len > 0 &&
3440                     atomic_read(&(cur->jlist->j_commit_left)) > 0 && cur->bh &&
3441                     cur->blocknr && cur->sb == sb && cur->blocknr == blocknr) {
3442                         can_dirty = 0;
3443                 }
3444                 cur = cur->hnext;
3445         }
3446         return can_dirty;
3447 }
3448
3449 /* syncs the commit blocks, but does not force the real buffers to disk
3450 ** will wait until the current transaction is done/committed before returning
3451 */
3452 int journal_end_sync(struct reiserfs_transaction_handle *th,
3453                      struct super_block *sb, unsigned long nblocks)
3454 {
3455         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3456
3457         BUG_ON(!th->t_trans_id);
3458         /* you can sync while nested, very, very bad */
3459         BUG_ON(th->t_refcount > 1);
3460         if (journal->j_len == 0) {
3461                 reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
3462                                              1);
3463                 journal_mark_dirty(th, sb, SB_BUFFER_WITH_SB(sb));
3464         }
3465         return do_journal_end(th, sb, nblocks, COMMIT_NOW | WAIT);
3466 }
3467
3468 /*
3469 ** writeback the pending async commits to disk
3470 */
3471 static void flush_async_commits(struct work_struct *work)
3472 {
3473         struct reiserfs_journal *journal =
3474                 container_of(work, struct reiserfs_journal, j_work.work);
3475         struct super_block *sb = journal->j_work_sb;
3476         struct reiserfs_journal_list *jl;
3477         struct list_head *entry;
3478
3479         reiserfs_write_lock(sb);
3480         if (!list_empty(&journal->j_journal_list)) {
3481                 /* last entry is the youngest, commit it and you get everything */
3482                 entry = journal->j_journal_list.prev;
3483                 jl = JOURNAL_LIST_ENTRY(entry);
3484                 flush_commit_list(sb, jl, 1);
3485         }
3486         reiserfs_write_unlock(sb);
3487 }
3488
3489 /*
3490 ** flushes any old transactions to disk
3491 ** ends the current transaction if it is too old
3492 */
3493 void reiserfs_flush_old_commits(struct super_block *sb)
3494 {
3495         time_t now;
3496         struct reiserfs_transaction_handle th;
3497         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3498
3499         now = get_seconds();
3500         /* safety check so we don't flush while we are replaying the log during
3501          * mount
3502          */
3503         if (list_empty(&journal->j_journal_list))
3504                 return;
3505
3506         /* check the current transaction.  If there are no writers, and it is
3507          * too old, finish it, and force the commit blocks to disk
3508          */
3509         if (atomic_read(&journal->j_wcount) <= 0 &&
3510             journal->j_trans_start_time > 0 &&
3511             journal->j_len > 0 &&
3512             (now - journal->j_trans_start_time) > journal->j_max_trans_age) {
3513                 if (!journal_join(&th, sb, 1)) {
3514                         reiserfs_prepare_for_journal(sb,
3515                                                      SB_BUFFER_WITH_SB(sb),
3516                                                      1);
3517                         journal_mark_dirty(&th, sb,
3518                                            SB_BUFFER_WITH_SB(sb));
3519
3520                         /* we're only being called from kreiserfsd, it makes no sense to do
3521                          ** an async commit so that kreiserfsd can do it later
3522                          */
3523                         do_journal_end(&th, sb, 1, COMMIT_NOW | WAIT);
3524                 }
3525         }
3526 }
3527
3528 /*
3529 ** returns 0 if do_journal_end should return right away, returns 1 if do_journal_end should finish the commit
3530 **
3531 ** if the current transaction is too old, but still has writers, this will wait on j_join_wait until all
3532 ** the writers are done.  By the time it wakes up, the transaction it was called has already ended, so it just
3533 ** flushes the commit list and returns 0.
3534 **
3535 ** Won't batch when flush or commit_now is set.  Also won't batch when others are waiting on j_join_wait.
3536 **
3537 ** Note, we can't allow the journal_end to proceed while there are still writers in the log.
3538 */
3539 static int check_journal_end(struct reiserfs_transaction_handle *th,
3540                              struct super_block *sb, unsigned long nblocks,
3541                              int flags)
3542 {
3543
3544         time_t now;
3545         int flush = flags & FLUSH_ALL;
3546         int commit_now = flags & COMMIT_NOW;
3547         int wait_on_commit = flags & WAIT;
3548         struct reiserfs_journal_list *jl;
3549         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3550
3551         BUG_ON(!th->t_trans_id);
3552
3553         if (th->t_trans_id != journal->j_trans_id) {
3554                 reiserfs_panic(th->t_super, "journal-1577",
3555                                "handle trans id %ld != current trans id %ld",
3556                                th->t_trans_id, journal->j_trans_id);
3557         }
3558
3559         journal->j_len_alloc -= (th->t_blocks_allocated - th->t_blocks_logged);
3560         if (atomic_read(&(journal->j_wcount)) > 0) {    /* <= 0 is allowed.  unmounting might not call begin */
3561                 atomic_dec(&(journal->j_wcount));
3562         }
3563
3564         /* BUG, deal with case where j_len is 0, but people previously freed blocks need to be released
3565          ** will be dealt with by next transaction that actually writes something, but should be taken
3566          ** care of in this trans
3567          */
3568         BUG_ON(journal->j_len == 0);
3569
3570         /* if wcount > 0, and we are called to with flush or commit_now,
3571          ** we wait on j_join_wait.  We will wake up when the last writer has
3572          ** finished the transaction, and started it on its way to the disk.
3573          ** Then, we flush the commit or journal list, and just return 0
3574          ** because the rest of journal end was already done for this transaction.
3575          */
3576         if (atomic_read(&(journal->j_wcount)) > 0) {
3577                 if (flush || commit_now) {
3578                         unsigned trans_id;
3579
3580                         jl = journal->j_current_jl;
3581                         trans_id = jl->j_trans_id;
3582                         if (wait_on_commit)
3583                                 jl->j_state |= LIST_COMMIT_PENDING;
3584                         atomic_set(&(journal->j_jlock), 1);
3585                         if (flush) {
3586                                 journal->j_next_full_flush = 1;
3587                         }
3588                         unlock_journal(sb);
3589
3590                         /* sleep while the current transaction is still j_jlocked */
3591                         while (journal->j_trans_id == trans_id) {
3592                                 if (atomic_read(&journal->j_jlock)) {
3593                                         queue_log_writer(sb);
3594                                 } else {
3595                                         lock_journal(sb);
3596                                         if (journal->j_trans_id == trans_id) {
3597                                                 atomic_set(&(journal->j_jlock),
3598                                                            1);
3599                                         }
3600                                         unlock_journal(sb);
3601                                 }
3602                         }
3603                         BUG_ON(journal->j_trans_id == trans_id);
3604                         
3605                         if (commit_now
3606                             && journal_list_still_alive(sb, trans_id)
3607                             && wait_on_commit) {
3608                                 flush_commit_list(sb, jl, 1);
3609                         }
3610                         return 0;
3611                 }
3612                 unlock_journal(sb);
3613                 return 0;
3614         }
3615
3616         /* deal with old transactions where we are the last writers */
3617         now = get_seconds();
3618         if ((now - journal->j_trans_start_time) > journal->j_max_trans_age) {
3619                 commit_now = 1;
3620                 journal->j_next_async_flush = 1;
3621         }
3622         /* don't batch when someone is waiting on j_join_wait */
3623         /* don't batch when syncing the commit or flushing the whole trans */
3624         if (!(journal->j_must_wait > 0) && !(atomic_read(&(journal->j_jlock)))
3625             && !flush && !commit_now && (journal->j_len < journal->j_max_batch)
3626             && journal->j_len_alloc < journal->j_max_batch
3627             && journal->j_cnode_free > (journal->j_trans_max * 3)) {
3628                 journal->j_bcount++;
3629                 unlock_journal(sb);
3630                 return 0;
3631         }
3632
3633         if (journal->j_start > SB_ONDISK_JOURNAL_SIZE(sb)) {
3634                 reiserfs_panic(sb, "journal-003",
3635                                "j_start (%ld) is too high",
3636                                journal->j_start);
3637         }
3638         return 1;
3639 }
3640
3641 /*
3642 ** Does all the work that makes deleting blocks safe.
3643 ** when deleting a block mark BH_JNew, just remove it from the current transaction, clean it's buffer_head and move on.
3644 **
3645 ** otherwise:
3646 ** set a bit for the block in the journal bitmap.  That will prevent it from being allocated for unformatted nodes
3647 ** before this transaction has finished.
3648 **
3649 ** mark any cnodes for this block as BLOCK_FREED, and clear their bh pointers.  That will prevent any old transactions with
3650 ** this block from trying to flush to the real location.  Since we aren't removing the cnode from the journal_list_hash,
3651 ** the block can't be reallocated yet.
3652 **
3653 ** Then remove it from the current transaction, decrementing any counters and filing it on the clean list.
3654 */
3655 int journal_mark_freed(struct reiserfs_transaction_handle *th,
3656                        struct super_block *sb, b_blocknr_t blocknr)
3657 {
3658         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3659         struct reiserfs_journal_cnode *cn = NULL;
3660         struct buffer_head *bh = NULL;
3661         struct reiserfs_list_bitmap *jb = NULL;
3662         int cleaned = 0;
3663         BUG_ON(!th->t_trans_id);
3664
3665         cn = get_journal_hash_dev(sb, journal->j_hash_table, blocknr);
3666         if (cn && cn->bh) {
3667                 bh = cn->bh;
3668                 get_bh(bh);
3669         }
3670         /* if it is journal new, we just remove it from this transaction */
3671         if (bh && buffer_journal_new(bh)) {
3672                 clear_buffer_journal_new(bh);
3673                 clear_prepared_bits(bh);
3674                 reiserfs_clean_and_file_buffer(bh);
3675                 cleaned = remove_from_transaction(sb, blocknr, cleaned);
3676         } else {
3677                 /* set the bit for this block in the journal bitmap for this transaction */
3678                 jb = journal->j_current_jl->j_list_bitmap;
3679                 if (!jb) {
3680                         reiserfs_panic(sb, "journal-1702",
3681                                        "journal_list_bitmap is NULL");
3682                 }
3683                 set_bit_in_list_bitmap(sb, blocknr, jb);
3684
3685                 /* Note, the entire while loop is not allowed to schedule.  */
3686
3687                 if (bh) {
3688                         clear_prepared_bits(bh);
3689                         reiserfs_clean_and_file_buffer(bh);
3690                 }
3691                 cleaned = remove_from_transaction(sb, blocknr, cleaned);
3692
3693                 /* find all older transactions with this block, make sure they don't try to write it out */
3694                 cn = get_journal_hash_dev(sb, journal->j_list_hash_table,
3695                                           blocknr);
3696                 while (cn) {
3697                         if (sb == cn->sb && blocknr == cn->blocknr) {
3698                                 set_bit(BLOCK_FREED, &cn->state);
3699                                 if (cn->bh) {
3700                                         if (!cleaned) {
3701                                                 /* remove_from_transaction will brelse the buffer if it was 
3702                                                  ** in the current trans
3703                                                  */
3704                                                 clear_buffer_journal_dirty(cn->
3705                                                                            bh);
3706                                                 clear_buffer_dirty(cn->bh);
3707                                                 clear_buffer_journal_test(cn->
3708                                                                           bh);
3709                                                 cleaned = 1;
3710                                                 put_bh(cn->bh);
3711                                                 if (atomic_read
3712                                                     (&(cn->bh->b_count)) < 0) {
3713                                                         reiserfs_warning(sb,
3714                                                                  "journal-2138",
3715                                                                  "cn->bh->b_count < 0");
3716                                                 }
3717                                         }
3718                                         if (cn->jlist) {        /* since we are clearing the bh, we MUST dec nonzerolen */
3719                                                 atomic_dec(&
3720                                                            (cn->jlist->
3721                                                             j_nonzerolen));
3722                                         }
3723                                         cn->bh = NULL;
3724                                 }
3725                         }
3726                         cn = cn->hnext;
3727                 }
3728         }
3729
3730         if (bh)
3731                 release_buffer_page(bh); /* get_hash grabs the buffer */
3732         return 0;
3733 }
3734
3735 void reiserfs_update_inode_transaction(struct inode *inode)
3736 {
3737         struct reiserfs_journal *journal = SB_JOURNAL(inode->i_sb);
3738         REISERFS_I(inode)->i_jl = journal->j_current_jl;
3739         REISERFS_I(inode)->i_trans_id = journal->j_trans_id;
3740 }
3741
3742 /*
3743  * returns -1 on error, 0 if no commits/barriers were done and 1
3744  * if a transaction was actually committed and the barrier was done
3745  */
3746 static int __commit_trans_jl(struct inode *inode, unsigned long id,
3747                              struct reiserfs_journal_list *jl)
3748 {
3749         struct reiserfs_transaction_handle th;
3750         struct super_block *sb = inode->i_sb;
3751         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3752         int ret = 0;
3753
3754         /* is it from the current transaction, or from an unknown transaction? */
3755         if (id == journal->j_trans_id) {
3756                 jl = journal->j_current_jl;
3757                 /* try to let other writers come in and grow this transaction */
3758                 let_transaction_grow(sb, id);
3759                 if (journal->j_trans_id != id) {
3760                         goto flush_commit_only;
3761                 }
3762
3763                 ret = journal_begin(&th, sb, 1);
3764                 if (ret)
3765                         return ret;
3766
3767                 /* someone might have ended this transaction while we joined */
3768                 if (journal->j_trans_id != id) {
3769                         reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
3770                                                      1);
3771                         journal_mark_dirty(&th, sb, SB_BUFFER_WITH_SB(sb));
3772                         ret = journal_end(&th, sb, 1);
3773                         goto flush_commit_only;
3774                 }
3775
3776                 ret = journal_end_sync(&th, sb, 1);
3777                 if (!ret)
3778                         ret = 1;
3779
3780         } else {
3781                 /* this gets tricky, we have to make sure the journal list in
3782                  * the inode still exists.  We know the list is still around
3783                  * if we've got a larger transaction id than the oldest list
3784                  */
3785               flush_commit_only:
3786                 if (journal_list_still_alive(inode->i_sb, id)) {
3787                         /*
3788                          * we only set ret to 1 when we know for sure
3789                          * the barrier hasn't been started yet on the commit
3790                          * block.
3791                          */
3792                         if (atomic_read(&jl->j_commit_left) > 1)
3793                                 ret = 1;
3794                         flush_commit_list(sb, jl, 1);
3795                         if (journal->j_errno)
3796                                 ret = journal->j_errno;
3797                 }
3798         }
3799         /* otherwise the list is gone, and long since committed */
3800         return ret;
3801 }
3802
3803 int reiserfs_commit_for_inode(struct inode *inode)
3804 {
3805         unsigned int id = REISERFS_I(inode)->i_trans_id;
3806         struct reiserfs_journal_list *jl = REISERFS_I(inode)->i_jl;
3807
3808         /* for the whole inode, assume unset id means it was
3809          * changed in the current transaction.  More conservative
3810          */
3811         if (!id || !jl) {
3812                 reiserfs_update_inode_transaction(inode);
3813                 id = REISERFS_I(inode)->i_trans_id;
3814                 /* jl will be updated in __commit_trans_jl */
3815         }
3816
3817         return __commit_trans_jl(inode, id, jl);
3818 }
3819
3820 void reiserfs_restore_prepared_buffer(struct super_block *sb,
3821                                       struct buffer_head *bh)
3822 {
3823         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3824         PROC_INFO_INC(sb, journal.restore_prepared);
3825         if (!bh) {
3826                 return;
3827         }
3828         if (test_clear_buffer_journal_restore_dirty(bh) &&
3829             buffer_journal_dirty(bh)) {
3830                 struct reiserfs_journal_cnode *cn;
3831                 reiserfs_write_lock(sb);
3832                 cn = get_journal_hash_dev(sb,
3833                                           journal->j_list_hash_table,
3834                                           bh->b_blocknr);
3835                 if (cn && can_dirty(cn)) {
3836                         set_buffer_journal_test(bh);
3837                         mark_buffer_dirty(bh);
3838                 }
3839                 reiserfs_write_unlock(sb);
3840         }
3841         clear_buffer_journal_prepared(bh);
3842 }
3843
3844 extern struct tree_balance *cur_tb;
3845 /*
3846 ** before we can change a metadata block, we have to make sure it won't
3847 ** be written to disk while we are altering it.  So, we must:
3848 ** clean it
3849 ** wait on it.
3850 **
3851 */
3852 int reiserfs_prepare_for_journal(struct super_block *sb,
3853                                  struct buffer_head *bh, int wait)
3854 {
3855         PROC_INFO_INC(sb, journal.prepare);
3856
3857         if (!trylock_buffer(bh)) {
3858                 if (!wait)
3859                         return 0;
3860                 lock_buffer(bh);
3861         }
3862         set_buffer_journal_prepared(bh);
3863         if (test_clear_buffer_dirty(bh) && buffer_journal_dirty(bh)) {
3864                 clear_buffer_journal_test(bh);
3865                 set_buffer_journal_restore_dirty(bh);
3866         }
3867         unlock_buffer(bh);
3868         return 1;
3869 }
3870
3871 static void flush_old_journal_lists(struct super_block *s)
3872 {
3873         struct reiserfs_journal *journal = SB_JOURNAL(s);
3874         struct reiserfs_journal_list *jl;
3875         struct list_head *entry;
3876         time_t now = get_seconds();
3877
3878         while (!list_empty(&journal->j_journal_list)) {
3879                 entry = journal->j_journal_list.next;
3880                 jl = JOURNAL_LIST_ENTRY(entry);
3881                 /* this check should always be run, to send old lists to disk */
3882                 if (jl->j_timestamp < (now - (JOURNAL_MAX_TRANS_AGE * 4)) &&
3883                     atomic_read(&jl->j_commit_left) == 0 &&
3884                     test_transaction(s, jl)) {
3885                         flush_used_journal_lists(s, jl);
3886                 } else {
3887                         break;
3888                 }
3889         }
3890 }
3891
3892 /*
3893 ** long and ugly.  If flush, will not return until all commit
3894 ** blocks and all real buffers in the trans are on disk.
3895 ** If no_async, won't return until all commit blocks are on disk.
3896 **
3897 ** keep reading, there are comments as you go along
3898 **
3899 ** If the journal is aborted, we just clean up. Things like flushing
3900 ** journal lists, etc just won't happen.
3901 */
3902 static int do_journal_end(struct reiserfs_transaction_handle *th,
3903                           struct super_block *sb, unsigned long nblocks,
3904                           int flags)
3905 {
3906         struct reiserfs_journal *journal = SB_JOURNAL(sb);
3907         struct reiserfs_journal_cnode *cn, *next, *jl_cn;
3908         struct reiserfs_journal_cnode *last_cn = NULL;
3909         struct reiserfs_journal_desc *desc;
3910         struct reiserfs_journal_commit *commit;
3911         struct buffer_head *c_bh;       /* commit bh */
3912         struct buffer_head *d_bh;       /* desc bh */
3913         int cur_write_start = 0;        /* start index of current log write */
3914         int old_start;
3915         int i;
3916         int flush;
3917         int wait_on_commit;
3918         struct reiserfs_journal_list *jl, *temp_jl;
3919         struct list_head *entry, *safe;
3920         unsigned long jindex;
3921         unsigned int commit_trans_id;
3922         int trans_half;
3923         int depth;
3924
3925         BUG_ON(th->t_refcount > 1);
3926         BUG_ON(!th->t_trans_id);
3927
3928         /* protect flush_older_commits from doing mistakes if the
3929            transaction ID counter gets overflowed.  */
3930         if (th->t_trans_id == ~0U)
3931                 flags |= FLUSH_ALL | COMMIT_NOW | WAIT;
3932         flush = flags & FLUSH_ALL;
3933         wait_on_commit = flags & WAIT;
3934
3935         current->journal_info = th->t_handle_save;
3936         reiserfs_check_lock_depth(sb, "journal end");
3937         if (journal->j_len == 0) {
3938                 reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
3939                                              1);
3940                 journal_mark_dirty(th, sb, SB_BUFFER_WITH_SB(sb));
3941         }
3942
3943         lock_journal(sb);
3944         if (journal->j_next_full_flush) {
3945                 flags |= FLUSH_ALL;
3946                 flush = 1;
3947         }
3948         if (journal->j_next_async_flush) {
3949                 flags |= COMMIT_NOW | WAIT;
3950                 wait_on_commit = 1;
3951         }
3952
3953         /* check_journal_end locks the journal, and unlocks if it does not return 1
3954          ** it tells us if we should continue with the journal_end, or just return
3955          */
3956         if (!check_journal_end(th, sb, nblocks, flags)) {
3957                 reiserfs_schedule_old_flush(sb);
3958                 wake_queued_writers(sb);
3959                 reiserfs_async_progress_wait(sb);
3960                 goto out;
3961         }
3962
3963         /* check_journal_end might set these, check again */
3964         if (journal->j_next_full_flush) {
3965                 flush = 1;
3966         }
3967
3968         /*
3969          ** j must wait means we have to flush the log blocks, and the real blocks for
3970          ** this transaction
3971          */
3972         if (journal->j_must_wait > 0) {
3973                 flush = 1;
3974         }
3975 #ifdef REISERFS_PREALLOCATE
3976         /* quota ops might need to nest, setup the journal_info pointer for them
3977          * and raise the refcount so that it is > 0. */
3978         current->journal_info = th;
3979         th->t_refcount++;
3980         reiserfs_discard_all_prealloc(th);      /* it should not involve new blocks into
3981                                                  * the transaction */
3982         th->t_refcount--;
3983         current->journal_info = th->t_handle_save;
3984 #endif
3985
3986         /* setup description block */
3987         d_bh =
3988             journal_getblk(sb,
3989                            SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
3990                            journal->j_start);
3991         set_buffer_uptodate(d_bh);
3992         desc = (struct reiserfs_journal_desc *)(d_bh)->b_data;
3993         memset(d_bh->b_data, 0, d_bh->b_size);
3994         memcpy(get_journal_desc_magic(d_bh), JOURNAL_DESC_MAGIC, 8);
3995         set_desc_trans_id(desc, journal->j_trans_id);
3996
3997         /* setup commit block.  Don't write (keep it clean too) this one until after everyone else is written */
3998         c_bh = journal_getblk(sb, SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
3999                               ((journal->j_start + journal->j_len +
4000                                 1) % SB_ONDISK_JOURNAL_SIZE(sb)));
4001         commit = (struct reiserfs_journal_commit *)c_bh->b_data;
4002         memset(c_bh->b_data, 0, c_bh->b_size);
4003         set_commit_trans_id(commit, journal->j_trans_id);
4004         set_buffer_uptodate(c_bh);
4005
4006         /* init this journal list */
4007         jl = journal->j_current_jl;
4008
4009         /* we lock the commit before doing anything because
4010          * we want to make sure nobody tries to run flush_commit_list until
4011          * the new transaction is fully setup, and we've already flushed the
4012          * ordered bh list
4013          */
4014         reiserfs_mutex_lock_safe(&jl->j_commit_mutex, sb);
4015
4016         /* save the transaction id in case we need to commit it later */
4017         commit_trans_id = jl->j_trans_id;
4018
4019         atomic_set(&jl->j_older_commits_done, 0);
4020         jl->j_trans_id = journal->j_trans_id;
4021         jl->j_timestamp = journal->j_trans_start_time;
4022         jl->j_commit_bh = c_bh;
4023         jl->j_start = journal->j_start;
4024         jl->j_len = journal->j_len;
4025         atomic_set(&jl->j_nonzerolen, journal->j_len);
4026         atomic_set(&jl->j_commit_left, journal->j_len + 2);
4027         jl->j_realblock = NULL;
4028
4029         /* The ENTIRE FOR LOOP MUST not cause schedule to occur.
4030          **  for each real block, add it to the journal list hash,
4031          ** copy into real block index array in the commit or desc block
4032          */
4033         trans_half = journal_trans_half(sb->s_blocksize);
4034         for (i = 0, cn = journal->j_first; cn; cn = cn->next, i++) {
4035                 if (buffer_journaled(cn->bh)) {
4036                         jl_cn = get_cnode(sb);
4037                         if (!jl_cn) {
4038                                 reiserfs_panic(sb, "journal-1676",
4039                                                "get_cnode returned NULL");
4040                         }
4041                         if (i == 0) {
4042                                 jl->j_realblock = jl_cn;
4043                         }
4044                         jl_cn->prev = last_cn;
4045                         jl_cn->next = NULL;
4046                         if (last_cn) {
4047                                 last_cn->next = jl_cn;
4048                         }
4049                         last_cn = jl_cn;
4050                         /* make sure the block we are trying to log is not a block
4051                            of journal or reserved area */
4052
4053                         if (is_block_in_log_or_reserved_area
4054                             (sb, cn->bh->b_blocknr)) {
4055                                 reiserfs_panic(sb, "journal-2332",
4056                                                "Trying to log block %lu, "
4057                                                "which is a log block",
4058                                                cn->bh->b_blocknr);
4059                         }
4060                         jl_cn->blocknr = cn->bh->b_blocknr;
4061                         jl_cn->state = 0;
4062                         jl_cn->sb = sb;
4063                         jl_cn->bh = cn->bh;
4064                         jl_cn->jlist = jl;
4065                         insert_journal_hash(journal->j_list_hash_table, jl_cn);
4066                         if (i < trans_half) {
4067                                 desc->j_realblock[i] =
4068                                     cpu_to_le32(cn->bh->b_blocknr);
4069                         } else {
4070                                 commit->j_realblock[i - trans_half] =
4071                                     cpu_to_le32(cn->bh->b_blocknr);
4072                         }
4073                 } else {
4074                         i--;
4075                 }
4076         }
4077         set_desc_trans_len(desc, journal->j_len);
4078         set_desc_mount_id(desc, journal->j_mount_id);
4079         set_desc_trans_id(desc, journal->j_trans_id);
4080         set_commit_trans_len(commit, journal->j_len);
4081
4082         /* special check in case all buffers in the journal were marked for not logging */
4083         BUG_ON(journal->j_len == 0);
4084
4085         /* we're about to dirty all the log blocks, mark the description block
4086          * dirty now too.  Don't mark the commit block dirty until all the
4087          * others are on disk
4088          */
4089         mark_buffer_dirty(d_bh);
4090
4091         /* first data block is j_start + 1, so add one to cur_write_start wherever you use it */
4092         cur_write_start = journal->j_start;
4093         cn = journal->j_first;
4094         jindex = 1;             /* start at one so we don't get the desc again */
4095         while (cn) {
4096                 clear_buffer_journal_new(cn->bh);
4097                 /* copy all the real blocks into log area.  dirty log blocks */
4098                 if (buffer_journaled(cn->bh)) {
4099                         struct buffer_head *tmp_bh;
4100                         char *addr;
4101                         struct page *page;
4102                         tmp_bh =
4103                             journal_getblk(sb,
4104                                            SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
4105                                            ((cur_write_start +
4106                                              jindex) %
4107                                             SB_ONDISK_JOURNAL_SIZE(sb)));
4108                         set_buffer_uptodate(tmp_bh);
4109                         page = cn->bh->b_page;
4110                         addr = kmap(page);
4111                         memcpy(tmp_bh->b_data,
4112                                addr + offset_in_page(cn->bh->b_data),
4113                                cn->bh->b_size);
4114                         kunmap(page);
4115                         mark_buffer_dirty(tmp_bh);
4116                         jindex++;
4117                         set_buffer_journal_dirty(cn->bh);
4118                         clear_buffer_journaled(cn->bh);
4119                 } else {
4120                         /* JDirty cleared sometime during transaction.  don't log this one */
4121                         reiserfs_warning(sb, "journal-2048",
4122                                          "BAD, buffer in journal hash, "
4123                                          "but not JDirty!");
4124                         brelse(cn->bh);
4125                 }
4126                 next = cn->next;
4127                 free_cnode(sb, cn);
4128                 cn = next;
4129                 reiserfs_cond_resched(sb);
4130         }
4131
4132         /* we are done  with both the c_bh and d_bh, but
4133          ** c_bh must be written after all other commit blocks,
4134          ** so we dirty/relse c_bh in flush_commit_list, with commit_left <= 1.
4135          */
4136
4137         journal->j_current_jl = alloc_journal_list(sb);
4138
4139         /* now it is safe to insert this transaction on the main list */
4140         list_add_tail(&jl->j_list, &journal->j_journal_list);
4141         list_add_tail(&jl->j_working_list, &journal->j_working_list);
4142         journal->j_num_work_lists++;
4143
4144         /* reset journal values for the next transaction */
4145         old_start = journal->j_start;
4146         journal->j_start =
4147             (journal->j_start + journal->j_len +
4148              2) % SB_ONDISK_JOURNAL_SIZE(sb);
4149         atomic_set(&(journal->j_wcount), 0);
4150         journal->j_bcount = 0;
4151         journal->j_last = NULL;
4152         journal->j_first = NULL;
4153         journal->j_len = 0;
4154         journal->j_trans_start_time = 0;
4155         /* check for trans_id overflow */
4156         if (++journal->j_trans_id == 0)
4157                 journal->j_trans_id = 10;
4158         journal->j_current_jl->j_trans_id = journal->j_trans_id;
4159         journal->j_must_wait = 0;
4160         journal->j_len_alloc = 0;
4161         journal->j_next_full_flush = 0;
4162         journal->j_next_async_flush = 0;
4163         init_journal_hash(sb);
4164
4165         // make sure reiserfs_add_jh sees the new current_jl before we
4166         // write out the tails
4167         smp_mb();
4168
4169         /* tail conversion targets have to hit the disk before we end the
4170          * transaction.  Otherwise a later transaction might repack the tail
4171          * before this transaction commits, leaving the data block unflushed and
4172          * clean, if we crash before the later transaction commits, the data block
4173          * is lost.
4174          */
4175         if (!list_empty(&jl->j_tail_bh_list)) {
4176                 depth = reiserfs_write_unlock_nested(sb);
4177                 write_ordered_buffers(&journal->j_dirty_buffers_lock,
4178                                       journal, jl, &jl->j_tail_bh_list);
4179                 reiserfs_write_lock_nested(sb, depth);
4180         }
4181         BUG_ON(!list_empty(&jl->j_tail_bh_list));
4182         mutex_unlock(&jl->j_commit_mutex);
4183
4184         /* honor the flush wishes from the caller, simple commits can
4185          ** be done outside the journal lock, they are done below
4186          **
4187          ** if we don't flush the commit list right now, we put it into
4188          ** the work queue so the people waiting on the async progress work
4189          ** queue don't wait for this proc to flush journal lists and such.
4190          */
4191         if (flush) {
4192                 flush_commit_list(sb, jl, 1);
4193                 flush_journal_list(sb, jl, 1);
4194         } else if (!(jl->j_state & LIST_COMMIT_PENDING))
4195                 queue_delayed_work(commit_wq, &journal->j_work, HZ / 10);
4196
4197         /* if the next transaction has any chance of wrapping, flush
4198          ** transactions that might get overwritten.  If any journal lists are very
4199          ** old flush them as well.
4200          */
4201       first_jl:
4202         list_for_each_safe(entry, safe, &journal->j_journal_list) {
4203                 temp_jl = JOURNAL_LIST_ENTRY(entry);
4204                 if (journal->j_start <= temp_jl->j_start) {
4205                         if ((journal->j_start + journal->j_trans_max + 1) >=
4206                             temp_jl->j_start) {
4207                                 flush_used_journal_lists(sb, temp_jl);
4208                                 goto first_jl;
4209                         } else if ((journal->j_start +
4210                                     journal->j_trans_max + 1) <
4211                                    SB_ONDISK_JOURNAL_SIZE(sb)) {
4212                                 /* if we don't cross into the next transaction and we don't
4213                                  * wrap, there is no way we can overlap any later transactions
4214                                  * break now
4215                                  */
4216                                 break;
4217                         }
4218                 } else if ((journal->j_start +
4219                             journal->j_trans_max + 1) >
4220                            SB_ONDISK_JOURNAL_SIZE(sb)) {
4221                         if (((journal->j_start + journal->j_trans_max + 1) %
4222                              SB_ONDISK_JOURNAL_SIZE(sb)) >=
4223                             temp_jl->j_start) {
4224                                 flush_used_journal_lists(sb, temp_jl);
4225                                 goto first_jl;
4226                         } else {
4227                                 /* we don't overlap anything from out start to the end of the
4228                                  * log, and our wrapped portion doesn't overlap anything at
4229                                  * the start of the log.  We can break
4230                                  */
4231                                 break;
4232                         }
4233                 }
4234         }
4235         flush_old_journal_lists(sb);
4236
4237         journal->j_current_jl->j_list_bitmap =
4238             get_list_bitmap(sb, journal->j_current_jl);
4239
4240         if (!(journal->j_current_jl->j_list_bitmap)) {
4241                 reiserfs_panic(sb, "journal-1996",
4242                                "could not get a list bitmap");
4243         }
4244
4245         atomic_set(&(journal->j_jlock), 0);
4246         unlock_journal(sb);
4247         /* wake up any body waiting to join. */
4248         clear_bit(J_WRITERS_QUEUED, &journal->j_state);
4249         wake_up(&(journal->j_join_wait));
4250
4251         if (!flush && wait_on_commit &&
4252             journal_list_still_alive(sb, commit_trans_id)) {
4253                 flush_commit_list(sb, jl, 1);
4254         }
4255       out:
4256         reiserfs_check_lock_depth(sb, "journal end2");
4257
4258         memset(th, 0, sizeof(*th));
4259         /* Re-set th->t_super, so we can properly keep track of how many
4260          * persistent transactions there are. We need to do this so if this
4261          * call is part of a failed restart_transaction, we can free it later */
4262         th->t_super = sb;
4263
4264         return journal->j_errno;
4265 }
4266
4267 /* Send the file system read only and refuse new transactions */
4268 void reiserfs_abort_journal(struct super_block *sb, int errno)
4269 {
4270         struct reiserfs_journal *journal = SB_JOURNAL(sb);
4271         if (test_bit(J_ABORTED, &journal->j_state))
4272                 return;
4273
4274         if (!journal->j_errno)
4275                 journal->j_errno = errno;
4276
4277         sb->s_flags |= MS_RDONLY;
4278         set_bit(J_ABORTED, &journal->j_state);
4279
4280 #ifdef CONFIG_REISERFS_CHECK
4281         dump_stack();
4282 #endif
4283 }