xref: /linux/fs/reiserfs/journal.c (revision a23e1966932464e1c5226cb9ac4ce1d5fc10ba22)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Write ahead logging implementation copyright Chris Mason 2000
4  *
5  * The background commits make this code very interrelated, and
6  * overly complex.  I need to rethink things a bit....The major players:
7  *
8  * journal_begin -- call with the number of blocks you expect to log.
9  *                  If the current transaction is too
10  *		    old, it will block until the current transaction is
11  *		    finished, and then start a new one.
12  *		    Usually, your transaction will get joined in with
13  *                  previous ones for speed.
14  *
15  * journal_join  -- same as journal_begin, but won't block on the current
16  *                  transaction regardless of age.  Don't ever call
17  *                  this.  Ever.  There are only two places it should be
18  *                  called from, and they are both inside this file.
19  *
20  * journal_mark_dirty -- adds blocks into this transaction.  clears any flags
21  *                       that might make them get sent to disk
22  *                       and then marks them BH_JDirty.  Puts the buffer head
23  *                       into the current transaction hash.
24  *
25  * journal_end -- if the current transaction is batchable, it does nothing
26  *                   otherwise, it could do an async/synchronous commit, or
27  *                   a full flush of all log and real blocks in the
28  *                   transaction.
29  *
30  * flush_old_commits -- if the current transaction is too old, it is ended and
31  *                      commit blocks are sent to disk.  Forces commit blocks
32  *                      to disk for all backgrounded commits that have been
33  *                      around too long.
34  *		     -- Note, if you call this as an immediate flush from
35  *		        within kupdate, it will ignore the immediate flag
36  */
37 
38 #include <linux/time.h>
39 #include <linux/semaphore.h>
40 #include <linux/vmalloc.h>
41 #include "reiserfs.h"
42 #include <linux/kernel.h>
43 #include <linux/errno.h>
44 #include <linux/fcntl.h>
45 #include <linux/stat.h>
46 #include <linux/string.h>
47 #include <linux/buffer_head.h>
48 #include <linux/workqueue.h>
49 #include <linux/writeback.h>
50 #include <linux/blkdev.h>
51 #include <linux/backing-dev.h>
52 #include <linux/uaccess.h>
53 #include <linux/slab.h>
54 
55 
56 /* gets a struct reiserfs_journal_list * from a list head */
57 #define JOURNAL_LIST_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
58                                j_list))
59 
60 /* must be correct to keep the desc and commit structs at 4k */
61 #define JOURNAL_TRANS_HALF 1018
62 #define BUFNR 64		/*read ahead */
63 
64 /* cnode stat bits.  Move these into reiserfs_fs.h */
65 
66 /* this block was freed, and can't be written.  */
67 #define BLOCK_FREED 2
68 /* this block was freed during this transaction, and can't be written */
69 #define BLOCK_FREED_HOLDER 3
70 
71 /* used in flush_journal_list */
72 #define BLOCK_NEEDS_FLUSH 4
73 #define BLOCK_DIRTIED 5
74 
75 /* journal list state bits */
76 #define LIST_TOUCHED 1
77 #define LIST_DIRTY   2
78 #define LIST_COMMIT_PENDING  4	/* someone will commit this list */
79 
80 /* flags for do_journal_end */
81 #define FLUSH_ALL   1		/* flush commit and real blocks */
82 #define COMMIT_NOW  2		/* end and commit this transaction */
83 #define WAIT        4		/* wait for the log blocks to hit the disk */
84 
85 static int do_journal_end(struct reiserfs_transaction_handle *, int flags);
86 static int flush_journal_list(struct super_block *s,
87 			      struct reiserfs_journal_list *jl, int flushall);
88 static int flush_commit_list(struct super_block *s,
89 			     struct reiserfs_journal_list *jl, int flushall);
90 static int can_dirty(struct reiserfs_journal_cnode *cn);
91 static int journal_join(struct reiserfs_transaction_handle *th,
92 			struct super_block *sb);
93 static void release_journal_dev(struct reiserfs_journal *journal);
94 static void dirty_one_transaction(struct super_block *s,
95 				 struct reiserfs_journal_list *jl);
96 static void flush_async_commits(struct work_struct *work);
97 static void queue_log_writer(struct super_block *s);
98 
99 /* values for join in do_journal_begin_r */
100 enum {
101 	JBEGIN_REG = 0,		/* regular journal begin */
102 	/* join the running transaction if at all possible */
103 	JBEGIN_JOIN = 1,
104 	/* called from cleanup code, ignores aborted flag */
105 	JBEGIN_ABORT = 2,
106 };
107 
108 static int do_journal_begin_r(struct reiserfs_transaction_handle *th,
109 			      struct super_block *sb,
110 			      unsigned long nblocks, int join);
111 
112 static void init_journal_hash(struct super_block *sb)
113 {
114 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
115 	memset(journal->j_hash_table, 0,
116 	       JOURNAL_HASH_SIZE * sizeof(struct reiserfs_journal_cnode *));
117 }
118 
119 /*
120  * clears BH_Dirty and sticks the buffer on the clean list.  Called because
121  * I can't allow refile_buffer to make schedule happen after I've freed a
122  * block.  Look at remove_from_transaction and journal_mark_freed for
123  * more details.
124  */
125 static int reiserfs_clean_and_file_buffer(struct buffer_head *bh)
126 {
127 	if (bh) {
128 		clear_buffer_dirty(bh);
129 		clear_buffer_journal_test(bh);
130 	}
131 	return 0;
132 }
133 
134 static struct reiserfs_bitmap_node *allocate_bitmap_node(struct super_block
135 							 *sb)
136 {
137 	struct reiserfs_bitmap_node *bn;
138 	static int id;
139 
140 	bn = kmalloc(sizeof(struct reiserfs_bitmap_node), GFP_NOFS);
141 	if (!bn) {
142 		return NULL;
143 	}
144 	bn->data = kzalloc(sb->s_blocksize, GFP_NOFS);
145 	if (!bn->data) {
146 		kfree(bn);
147 		return NULL;
148 	}
149 	bn->id = id++;
150 	INIT_LIST_HEAD(&bn->list);
151 	return bn;
152 }
153 
154 static struct reiserfs_bitmap_node *get_bitmap_node(struct super_block *sb)
155 {
156 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
157 	struct reiserfs_bitmap_node *bn = NULL;
158 	struct list_head *entry = journal->j_bitmap_nodes.next;
159 
160 	journal->j_used_bitmap_nodes++;
161 repeat:
162 
163 	if (entry != &journal->j_bitmap_nodes) {
164 		bn = list_entry(entry, struct reiserfs_bitmap_node, list);
165 		list_del(entry);
166 		memset(bn->data, 0, sb->s_blocksize);
167 		journal->j_free_bitmap_nodes--;
168 		return bn;
169 	}
170 	bn = allocate_bitmap_node(sb);
171 	if (!bn) {
172 		yield();
173 		goto repeat;
174 	}
175 	return bn;
176 }
177 static inline void free_bitmap_node(struct super_block *sb,
178 				    struct reiserfs_bitmap_node *bn)
179 {
180 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
181 	journal->j_used_bitmap_nodes--;
182 	if (journal->j_free_bitmap_nodes > REISERFS_MAX_BITMAP_NODES) {
183 		kfree(bn->data);
184 		kfree(bn);
185 	} else {
186 		list_add(&bn->list, &journal->j_bitmap_nodes);
187 		journal->j_free_bitmap_nodes++;
188 	}
189 }
190 
191 static void allocate_bitmap_nodes(struct super_block *sb)
192 {
193 	int i;
194 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
195 	struct reiserfs_bitmap_node *bn = NULL;
196 	for (i = 0; i < REISERFS_MIN_BITMAP_NODES; i++) {
197 		bn = allocate_bitmap_node(sb);
198 		if (bn) {
199 			list_add(&bn->list, &journal->j_bitmap_nodes);
200 			journal->j_free_bitmap_nodes++;
201 		} else {
202 			/* this is ok, we'll try again when more are needed */
203 			break;
204 		}
205 	}
206 }
207 
208 static int set_bit_in_list_bitmap(struct super_block *sb,
209 				  b_blocknr_t block,
210 				  struct reiserfs_list_bitmap *jb)
211 {
212 	unsigned int bmap_nr = block / (sb->s_blocksize << 3);
213 	unsigned int bit_nr = block % (sb->s_blocksize << 3);
214 
215 	if (!jb->bitmaps[bmap_nr]) {
216 		jb->bitmaps[bmap_nr] = get_bitmap_node(sb);
217 	}
218 	set_bit(bit_nr, (unsigned long *)jb->bitmaps[bmap_nr]->data);
219 	return 0;
220 }
221 
222 static void cleanup_bitmap_list(struct super_block *sb,
223 				struct reiserfs_list_bitmap *jb)
224 {
225 	int i;
226 	if (jb->bitmaps == NULL)
227 		return;
228 
229 	for (i = 0; i < reiserfs_bmap_count(sb); i++) {
230 		if (jb->bitmaps[i]) {
231 			free_bitmap_node(sb, jb->bitmaps[i]);
232 			jb->bitmaps[i] = NULL;
233 		}
234 	}
235 }
236 
237 /*
238  * only call this on FS unmount.
239  */
240 static int free_list_bitmaps(struct super_block *sb,
241 			     struct reiserfs_list_bitmap *jb_array)
242 {
243 	int i;
244 	struct reiserfs_list_bitmap *jb;
245 	for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
246 		jb = jb_array + i;
247 		jb->journal_list = NULL;
248 		cleanup_bitmap_list(sb, jb);
249 		vfree(jb->bitmaps);
250 		jb->bitmaps = NULL;
251 	}
252 	return 0;
253 }
254 
255 static int free_bitmap_nodes(struct super_block *sb)
256 {
257 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
258 	struct list_head *next = journal->j_bitmap_nodes.next;
259 	struct reiserfs_bitmap_node *bn;
260 
261 	while (next != &journal->j_bitmap_nodes) {
262 		bn = list_entry(next, struct reiserfs_bitmap_node, list);
263 		list_del(next);
264 		kfree(bn->data);
265 		kfree(bn);
266 		next = journal->j_bitmap_nodes.next;
267 		journal->j_free_bitmap_nodes--;
268 	}
269 
270 	return 0;
271 }
272 
273 /*
274  * get memory for JOURNAL_NUM_BITMAPS worth of bitmaps.
275  * jb_array is the array to be filled in.
276  */
277 int reiserfs_allocate_list_bitmaps(struct super_block *sb,
278 				   struct reiserfs_list_bitmap *jb_array,
279 				   unsigned int bmap_nr)
280 {
281 	int i;
282 	int failed = 0;
283 	struct reiserfs_list_bitmap *jb;
284 	int mem = bmap_nr * sizeof(struct reiserfs_bitmap_node *);
285 
286 	for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
287 		jb = jb_array + i;
288 		jb->journal_list = NULL;
289 		jb->bitmaps = vzalloc(mem);
290 		if (!jb->bitmaps) {
291 			reiserfs_warning(sb, "clm-2000", "unable to "
292 					 "allocate bitmaps for journal lists");
293 			failed = 1;
294 			break;
295 		}
296 	}
297 	if (failed) {
298 		free_list_bitmaps(sb, jb_array);
299 		return -1;
300 	}
301 	return 0;
302 }
303 
304 /*
305  * find an available list bitmap.  If you can't find one, flush a commit list
306  * and try again
307  */
308 static struct reiserfs_list_bitmap *get_list_bitmap(struct super_block *sb,
309 						    struct reiserfs_journal_list
310 						    *jl)
311 {
312 	int i, j;
313 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
314 	struct reiserfs_list_bitmap *jb = NULL;
315 
316 	for (j = 0; j < (JOURNAL_NUM_BITMAPS * 3); j++) {
317 		i = journal->j_list_bitmap_index;
318 		journal->j_list_bitmap_index = (i + 1) % JOURNAL_NUM_BITMAPS;
319 		jb = journal->j_list_bitmap + i;
320 		if (journal->j_list_bitmap[i].journal_list) {
321 			flush_commit_list(sb,
322 					  journal->j_list_bitmap[i].
323 					  journal_list, 1);
324 			if (!journal->j_list_bitmap[i].journal_list) {
325 				break;
326 			}
327 		} else {
328 			break;
329 		}
330 	}
331 	/* double check to make sure if flushed correctly */
332 	if (jb->journal_list)
333 		return NULL;
334 	jb->journal_list = jl;
335 	return jb;
336 }
337 
338 /*
339  * allocates a new chunk of X nodes, and links them all together as a list.
340  * Uses the cnode->next and cnode->prev pointers
341  * returns NULL on failure
342  */
343 static struct reiserfs_journal_cnode *allocate_cnodes(int num_cnodes)
344 {
345 	struct reiserfs_journal_cnode *head;
346 	int i;
347 	if (num_cnodes <= 0) {
348 		return NULL;
349 	}
350 	head = vzalloc(array_size(num_cnodes,
351 				  sizeof(struct reiserfs_journal_cnode)));
352 	if (!head) {
353 		return NULL;
354 	}
355 	head[0].prev = NULL;
356 	head[0].next = head + 1;
357 	for (i = 1; i < num_cnodes; i++) {
358 		head[i].prev = head + (i - 1);
359 		head[i].next = head + (i + 1);	/* if last one, overwrite it after the if */
360 	}
361 	head[num_cnodes - 1].next = NULL;
362 	return head;
363 }
364 
365 /* pulls a cnode off the free list, or returns NULL on failure */
366 static struct reiserfs_journal_cnode *get_cnode(struct super_block *sb)
367 {
368 	struct reiserfs_journal_cnode *cn;
369 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
370 
371 	reiserfs_check_lock_depth(sb, "get_cnode");
372 
373 	if (journal->j_cnode_free <= 0) {
374 		return NULL;
375 	}
376 	journal->j_cnode_used++;
377 	journal->j_cnode_free--;
378 	cn = journal->j_cnode_free_list;
379 	if (!cn) {
380 		return cn;
381 	}
382 	if (cn->next) {
383 		cn->next->prev = NULL;
384 	}
385 	journal->j_cnode_free_list = cn->next;
386 	memset(cn, 0, sizeof(struct reiserfs_journal_cnode));
387 	return cn;
388 }
389 
390 /*
391  * returns a cnode to the free list
392  */
393 static void free_cnode(struct super_block *sb,
394 		       struct reiserfs_journal_cnode *cn)
395 {
396 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
397 
398 	reiserfs_check_lock_depth(sb, "free_cnode");
399 
400 	journal->j_cnode_used--;
401 	journal->j_cnode_free++;
402 	/* memset(cn, 0, sizeof(struct reiserfs_journal_cnode)) ; */
403 	cn->next = journal->j_cnode_free_list;
404 	if (journal->j_cnode_free_list) {
405 		journal->j_cnode_free_list->prev = cn;
406 	}
407 	cn->prev = NULL;	/* not needed with the memset, but I might kill the memset, and forget to do this */
408 	journal->j_cnode_free_list = cn;
409 }
410 
411 static void clear_prepared_bits(struct buffer_head *bh)
412 {
413 	clear_buffer_journal_prepared(bh);
414 	clear_buffer_journal_restore_dirty(bh);
415 }
416 
417 /*
418  * return a cnode with same dev, block number and size in table,
419  * or null if not found
420  */
421 static inline struct reiserfs_journal_cnode *get_journal_hash_dev(struct
422 								  super_block
423 								  *sb,
424 								  struct
425 								  reiserfs_journal_cnode
426 								  **table,
427 								  long bl)
428 {
429 	struct reiserfs_journal_cnode *cn;
430 	cn = journal_hash(table, sb, bl);
431 	while (cn) {
432 		if (cn->blocknr == bl && cn->sb == sb)
433 			return cn;
434 		cn = cn->hnext;
435 	}
436 	return (struct reiserfs_journal_cnode *)0;
437 }
438 
439 /*
440  * this actually means 'can this block be reallocated yet?'.  If you set
441  * search_all, a block can only be allocated if it is not in the current
442  * transaction, was not freed by the current transaction, and has no chance
443  * of ever being overwritten by a replay after crashing.
444  *
445  * If you don't set search_all, a block can only be allocated if it is not
446  * in the current transaction.  Since deleting a block removes it from the
447  * current transaction, this case should never happen.  If you don't set
448  * search_all, make 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
453  * that 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 int reiserfs_in_journal(struct super_block *sb,
459 			unsigned int bmap_nr, int bit_nr, int search_all,
460 			b_blocknr_t * next_zero_bit)
461 {
462 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
463 	struct reiserfs_list_bitmap *jb;
464 	int i;
465 	unsigned long bl;
466 
467 	*next_zero_bit = 0;	/* always start this at zero. */
468 
469 	PROC_INFO_INC(sb, journal.in_journal);
470 	/*
471 	 * If we aren't doing a search_all, this is a metablock, and it
472 	 * will be logged before use.  if we crash before the transaction
473 	 * that freed it commits,  this transaction won't have committed
474 	 * 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 	    && (get_journal_hash_dev(sb, journal->j_list_hash_table, bl))) {
499 		return 1;
500 	}
501 
502 	/* is it in the current transaction.  This should never happen */
503 	if ((get_journal_hash_dev(sb, journal->j_hash_table, bl))) {
504 		BUG();
505 		return 1;
506 	}
507 
508 	PROC_INFO_INC(sb, journal.in_journal_reusable);
509 	/* safe for reuse */
510 	return 0;
511 }
512 
513 /* insert cn into table */
514 static inline void insert_journal_hash(struct reiserfs_journal_cnode **table,
515 				       struct reiserfs_journal_cnode *cn)
516 {
517 	struct reiserfs_journal_cnode *cn_orig;
518 
519 	cn_orig = journal_hash(table, cn->sb, cn->blocknr);
520 	cn->hnext = cn_orig;
521 	cn->hprev = NULL;
522 	if (cn_orig) {
523 		cn_orig->hprev = cn;
524 	}
525 	journal_hash(table, cn->sb, cn->blocknr) = cn;
526 }
527 
528 /* lock the current transaction */
529 static inline void lock_journal(struct super_block *sb)
530 {
531 	PROC_INFO_INC(sb, journal.lock_journal);
532 
533 	reiserfs_mutex_lock_safe(&SB_JOURNAL(sb)->j_mutex, sb);
534 }
535 
536 /* unlock the current transaction */
537 static inline void unlock_journal(struct super_block *sb)
538 {
539 	mutex_unlock(&SB_JOURNAL(sb)->j_mutex);
540 }
541 
542 static inline void get_journal_list(struct reiserfs_journal_list *jl)
543 {
544 	jl->j_refcount++;
545 }
546 
547 static inline void put_journal_list(struct super_block *s,
548 				    struct reiserfs_journal_list *jl)
549 {
550 	if (jl->j_refcount < 1) {
551 		reiserfs_panic(s, "journal-2", "trans id %u, refcount at %d",
552 			       jl->j_trans_id, jl->j_refcount);
553 	}
554 	if (--jl->j_refcount == 0)
555 		kfree(jl);
556 }
557 
558 /*
559  * this used to be much more involved, and I'm keeping it just in case
560  * things get ugly again.  it gets called by flush_commit_list, and
561  * cleans up any data stored about blocks freed during a transaction.
562  */
563 static void cleanup_freed_for_journal_list(struct super_block *sb,
564 					   struct reiserfs_journal_list *jl)
565 {
566 
567 	struct reiserfs_list_bitmap *jb = jl->j_list_bitmap;
568 	if (jb) {
569 		cleanup_bitmap_list(sb, jb);
570 	}
571 	jl->j_list_bitmap->journal_list = NULL;
572 	jl->j_list_bitmap = NULL;
573 }
574 
575 static int journal_list_still_alive(struct super_block *s,
576 				    unsigned int trans_id)
577 {
578 	struct reiserfs_journal *journal = SB_JOURNAL(s);
579 	struct list_head *entry = &journal->j_journal_list;
580 	struct reiserfs_journal_list *jl;
581 
582 	if (!list_empty(entry)) {
583 		jl = JOURNAL_LIST_ENTRY(entry->next);
584 		if (jl->j_trans_id <= trans_id) {
585 			return 1;
586 		}
587 	}
588 	return 0;
589 }
590 
591 /*
592  * If page->mapping was null, we failed to truncate this page for
593  * some reason.  Most likely because it was truncated after being
594  * logged via data=journal.
595  *
596  * This does a check to see if the buffer belongs to one of these
597  * lost pages before doing the final put_bh.  If page->mapping was
598  * null, it tries to free buffers on the page, which should make the
599  * final put_page drop the page from the lru.
600  */
601 static void release_buffer_page(struct buffer_head *bh)
602 {
603 	struct folio *folio = bh->b_folio;
604 	if (!folio->mapping && folio_trylock(folio)) {
605 		folio_get(folio);
606 		put_bh(bh);
607 		if (!folio->mapping)
608 			try_to_free_buffers(folio);
609 		folio_unlock(folio);
610 		folio_put(folio);
611 	} else {
612 		put_bh(bh);
613 	}
614 }
615 
616 static void reiserfs_end_buffer_io_sync(struct buffer_head *bh, int uptodate)
617 {
618 	if (buffer_journaled(bh)) {
619 		reiserfs_warning(NULL, "clm-2084",
620 				 "pinned buffer %lu:%pg sent to disk",
621 				 bh->b_blocknr, bh->b_bdev);
622 	}
623 	if (uptodate)
624 		set_buffer_uptodate(bh);
625 	else
626 		clear_buffer_uptodate(bh);
627 
628 	unlock_buffer(bh);
629 	release_buffer_page(bh);
630 }
631 
632 static void reiserfs_end_ordered_io(struct buffer_head *bh, int uptodate)
633 {
634 	if (uptodate)
635 		set_buffer_uptodate(bh);
636 	else
637 		clear_buffer_uptodate(bh);
638 	unlock_buffer(bh);
639 	put_bh(bh);
640 }
641 
642 static void submit_logged_buffer(struct buffer_head *bh)
643 {
644 	get_bh(bh);
645 	bh->b_end_io = reiserfs_end_buffer_io_sync;
646 	clear_buffer_journal_new(bh);
647 	clear_buffer_dirty(bh);
648 	if (!test_clear_buffer_journal_test(bh))
649 		BUG();
650 	if (!buffer_uptodate(bh))
651 		BUG();
652 	submit_bh(REQ_OP_WRITE, bh);
653 }
654 
655 static void submit_ordered_buffer(struct buffer_head *bh)
656 {
657 	get_bh(bh);
658 	bh->b_end_io = reiserfs_end_ordered_io;
659 	clear_buffer_dirty(bh);
660 	if (!buffer_uptodate(bh))
661 		BUG();
662 	submit_bh(REQ_OP_WRITE, bh);
663 }
664 
665 #define CHUNK_SIZE 32
666 struct buffer_chunk {
667 	struct buffer_head *bh[CHUNK_SIZE];
668 	int nr;
669 };
670 
671 static void write_chunk(struct buffer_chunk *chunk)
672 {
673 	int i;
674 	for (i = 0; i < chunk->nr; i++) {
675 		submit_logged_buffer(chunk->bh[i]);
676 	}
677 	chunk->nr = 0;
678 }
679 
680 static void write_ordered_chunk(struct buffer_chunk *chunk)
681 {
682 	int i;
683 	for (i = 0; i < chunk->nr; i++) {
684 		submit_ordered_buffer(chunk->bh[i]);
685 	}
686 	chunk->nr = 0;
687 }
688 
689 static int add_to_chunk(struct buffer_chunk *chunk, struct buffer_head *bh,
690 			spinlock_t * lock, void (fn) (struct buffer_chunk *))
691 {
692 	int ret = 0;
693 	BUG_ON(chunk->nr >= CHUNK_SIZE);
694 	chunk->bh[chunk->nr++] = bh;
695 	if (chunk->nr >= CHUNK_SIZE) {
696 		ret = 1;
697 		if (lock) {
698 			spin_unlock(lock);
699 			fn(chunk);
700 			spin_lock(lock);
701 		} else {
702 			fn(chunk);
703 		}
704 	}
705 	return ret;
706 }
707 
708 static atomic_t nr_reiserfs_jh = ATOMIC_INIT(0);
709 static struct reiserfs_jh *alloc_jh(void)
710 {
711 	struct reiserfs_jh *jh;
712 	while (1) {
713 		jh = kmalloc(sizeof(*jh), GFP_NOFS);
714 		if (jh) {
715 			atomic_inc(&nr_reiserfs_jh);
716 			return jh;
717 		}
718 		yield();
719 	}
720 }
721 
722 /*
723  * we want to free the jh when the buffer has been written
724  * and waited on
725  */
726 void reiserfs_free_jh(struct buffer_head *bh)
727 {
728 	struct reiserfs_jh *jh;
729 
730 	jh = bh->b_private;
731 	if (jh) {
732 		bh->b_private = NULL;
733 		jh->bh = NULL;
734 		list_del_init(&jh->list);
735 		kfree(jh);
736 		if (atomic_read(&nr_reiserfs_jh) <= 0)
737 			BUG();
738 		atomic_dec(&nr_reiserfs_jh);
739 		put_bh(bh);
740 	}
741 }
742 
743 static inline int __add_jh(struct reiserfs_journal *j, struct buffer_head *bh,
744 			   int tail)
745 {
746 	struct reiserfs_jh *jh;
747 
748 	if (bh->b_private) {
749 		spin_lock(&j->j_dirty_buffers_lock);
750 		if (!bh->b_private) {
751 			spin_unlock(&j->j_dirty_buffers_lock);
752 			goto no_jh;
753 		}
754 		jh = bh->b_private;
755 		list_del_init(&jh->list);
756 	} else {
757 no_jh:
758 		get_bh(bh);
759 		jh = alloc_jh();
760 		spin_lock(&j->j_dirty_buffers_lock);
761 		/*
762 		 * buffer must be locked for __add_jh, should be able to have
763 		 * two adds at the same time
764 		 */
765 		BUG_ON(bh->b_private);
766 		jh->bh = bh;
767 		bh->b_private = jh;
768 	}
769 	jh->jl = j->j_current_jl;
770 	if (tail)
771 		list_add_tail(&jh->list, &jh->jl->j_tail_bh_list);
772 	else {
773 		list_add_tail(&jh->list, &jh->jl->j_bh_list);
774 	}
775 	spin_unlock(&j->j_dirty_buffers_lock);
776 	return 0;
777 }
778 
779 int reiserfs_add_tail_list(struct inode *inode, struct buffer_head *bh)
780 {
781 	return __add_jh(SB_JOURNAL(inode->i_sb), bh, 1);
782 }
783 int reiserfs_add_ordered_list(struct inode *inode, struct buffer_head *bh)
784 {
785 	return __add_jh(SB_JOURNAL(inode->i_sb), bh, 0);
786 }
787 
788 #define JH_ENTRY(l) list_entry((l), struct reiserfs_jh, list)
789 static int write_ordered_buffers(spinlock_t * lock,
790 				 struct reiserfs_journal *j,
791 				 struct reiserfs_journal_list *jl,
792 				 struct list_head *list)
793 {
794 	struct buffer_head *bh;
795 	struct reiserfs_jh *jh;
796 	int ret = j->j_errno;
797 	struct buffer_chunk chunk;
798 	struct list_head tmp;
799 	INIT_LIST_HEAD(&tmp);
800 
801 	chunk.nr = 0;
802 	spin_lock(lock);
803 	while (!list_empty(list)) {
804 		jh = JH_ENTRY(list->next);
805 		bh = jh->bh;
806 		get_bh(bh);
807 		if (!trylock_buffer(bh)) {
808 			if (!buffer_dirty(bh)) {
809 				list_move(&jh->list, &tmp);
810 				goto loop_next;
811 			}
812 			spin_unlock(lock);
813 			if (chunk.nr)
814 				write_ordered_chunk(&chunk);
815 			wait_on_buffer(bh);
816 			cond_resched();
817 			spin_lock(lock);
818 			goto loop_next;
819 		}
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 		/*
860 		 * ugly interaction with invalidate_folio here.
861 		 * reiserfs_invalidate_folio will pin any buffer that has a
862 		 * valid journal head from an older transaction.  If someone
863 		 * else sets our buffer dirty after we write it in the first
864 		 * loop, and then someone truncates the page away, nobody
865 		 * will ever write the buffer. We're safe if we write the
866 		 * page one last time after freeing the journal header.
867 		 */
868 		if (buffer_dirty(bh) && unlikely(bh->b_folio->mapping == NULL)) {
869 			spin_unlock(lock);
870 			write_dirty_buffer(bh, 0);
871 			spin_lock(lock);
872 		}
873 		put_bh(bh);
874 		cond_resched_lock(lock);
875 	}
876 	spin_unlock(lock);
877 	return ret;
878 }
879 
880 static int flush_older_commits(struct super_block *s,
881 			       struct reiserfs_journal_list *jl)
882 {
883 	struct reiserfs_journal *journal = SB_JOURNAL(s);
884 	struct reiserfs_journal_list *other_jl;
885 	struct reiserfs_journal_list *first_jl;
886 	struct list_head *entry;
887 	unsigned int trans_id = jl->j_trans_id;
888 	unsigned int other_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 	entry = &first_jl->j_list;
912 	while (1) {
913 		other_jl = JOURNAL_LIST_ENTRY(entry);
914 		other_trans_id = other_jl->j_trans_id;
915 
916 		if (other_trans_id < trans_id) {
917 			if (atomic_read(&other_jl->j_commit_left) != 0) {
918 				flush_commit_list(s, other_jl, 0);
919 
920 				/* list we were called with is gone, return */
921 				if (!journal_list_still_alive(s, trans_id))
922 					return 1;
923 
924 				/*
925 				 * the one we just flushed is gone, this means
926 				 * all older lists are also gone, so first_jl
927 				 * is no longer valid either.  Go back to the
928 				 * 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 		wait_var_event_timeout(&j->j_async_throttle,
954 				       atomic_read(&j->j_async_throttle) == 0,
955 				       HZ / 10);
956 		reiserfs_write_lock_nested(s, depth);
957 	}
958 
959 	return 0;
960 }
961 
962 /*
963  * if this journal list still has commit blocks unflushed, send them to disk.
964  *
965  * log areas must be flushed in order (transaction 2 can't commit before
966  * transaction 1) Before the commit block can by written, every other log
967  * block must be safely on disk
968  */
969 static int flush_commit_list(struct super_block *s,
970 			     struct reiserfs_journal_list *jl, int flushall)
971 {
972 	int i;
973 	b_blocknr_t bn;
974 	struct buffer_head *tbh = NULL;
975 	unsigned int trans_id = jl->j_trans_id;
976 	struct reiserfs_journal *journal = SB_JOURNAL(s);
977 	int retval = 0;
978 	int write_len;
979 	int depth;
980 
981 	reiserfs_check_lock_depth(s, "flush_commit_list");
982 
983 	if (atomic_read(&jl->j_older_commits_done)) {
984 		return 0;
985 	}
986 
987 	/*
988 	 * before we can put our commit blocks on disk, we have to make
989 	 * sure everyone older than us is on disk too
990 	 */
991 	BUG_ON(jl->j_len <= 0);
992 	BUG_ON(trans_id == journal->j_trans_id);
993 
994 	get_journal_list(jl);
995 	if (flushall) {
996 		if (flush_older_commits(s, jl) == 1) {
997 			/*
998 			 * list disappeared during flush_older_commits.
999 			 * return
1000 			 */
1001 			goto put_jl;
1002 		}
1003 	}
1004 
1005 	/* make sure nobody is trying to flush this one at the same time */
1006 	reiserfs_mutex_lock_safe(&jl->j_commit_mutex, s);
1007 
1008 	if (!journal_list_still_alive(s, trans_id)) {
1009 		mutex_unlock(&jl->j_commit_mutex);
1010 		goto put_jl;
1011 	}
1012 	BUG_ON(jl->j_trans_id == 0);
1013 
1014 	/* this commit is done, exit */
1015 	if (atomic_read(&jl->j_commit_left) <= 0) {
1016 		if (flushall) {
1017 			atomic_set(&jl->j_older_commits_done, 1);
1018 		}
1019 		mutex_unlock(&jl->j_commit_mutex);
1020 		goto put_jl;
1021 	}
1022 
1023 	if (!list_empty(&jl->j_bh_list)) {
1024 		int ret;
1025 
1026 		/*
1027 		 * We might sleep in numerous places inside
1028 		 * write_ordered_buffers. Relax the write lock.
1029 		 */
1030 		depth = reiserfs_write_unlock_nested(s);
1031 		ret = write_ordered_buffers(&journal->j_dirty_buffers_lock,
1032 					    journal, jl, &jl->j_bh_list);
1033 		if (ret < 0 && retval == 0)
1034 			retval = ret;
1035 		reiserfs_write_lock_nested(s, depth);
1036 	}
1037 	BUG_ON(!list_empty(&jl->j_bh_list));
1038 	/*
1039 	 * for the description block and all the log blocks, submit any buffers
1040 	 * that haven't already reached the disk.  Try to write at least 256
1041 	 * log blocks. later on, we will only wait on blocks that correspond
1042 	 * to this transaction, but while we're unplugging we might as well
1043 	 * get a chunk of data on there.
1044 	 */
1045 	atomic_inc(&journal->j_async_throttle);
1046 	write_len = jl->j_len + 1;
1047 	if (write_len < 256)
1048 		write_len = 256;
1049 	for (i = 0 ; i < write_len ; i++) {
1050 		bn = SB_ONDISK_JOURNAL_1st_BLOCK(s) + (jl->j_start + i) %
1051 		    SB_ONDISK_JOURNAL_SIZE(s);
1052 		tbh = journal_find_get_block(s, bn);
1053 		if (tbh) {
1054 			if (buffer_dirty(tbh)) {
1055 		            depth = reiserfs_write_unlock_nested(s);
1056 			    write_dirty_buffer(tbh, 0);
1057 			    reiserfs_write_lock_nested(s, depth);
1058 			}
1059 			put_bh(tbh) ;
1060 		}
1061 	}
1062 	if (atomic_dec_and_test(&journal->j_async_throttle))
1063 		wake_up_var(&journal->j_async_throttle);
1064 
1065 	for (i = 0; i < (jl->j_len + 1); i++) {
1066 		bn = SB_ONDISK_JOURNAL_1st_BLOCK(s) +
1067 		    (jl->j_start + i) % SB_ONDISK_JOURNAL_SIZE(s);
1068 		tbh = journal_find_get_block(s, bn);
1069 
1070 		depth = reiserfs_write_unlock_nested(s);
1071 		__wait_on_buffer(tbh);
1072 		reiserfs_write_lock_nested(s, depth);
1073 		/*
1074 		 * since we're using ll_rw_blk above, it might have skipped
1075 		 * over a locked buffer.  Double check here
1076 		 */
1077 		/* redundant, sync_dirty_buffer() checks */
1078 		if (buffer_dirty(tbh)) {
1079 			depth = reiserfs_write_unlock_nested(s);
1080 			sync_dirty_buffer(tbh);
1081 			reiserfs_write_lock_nested(s, depth);
1082 		}
1083 		if (unlikely(!buffer_uptodate(tbh))) {
1084 #ifdef CONFIG_REISERFS_CHECK
1085 			reiserfs_warning(s, "journal-601",
1086 					 "buffer write failed");
1087 #endif
1088 			retval = -EIO;
1089 		}
1090 		/* once for journal_find_get_block */
1091 		put_bh(tbh);
1092 		/* once due to original getblk in do_journal_end */
1093 		put_bh(tbh);
1094 		atomic_dec(&jl->j_commit_left);
1095 	}
1096 
1097 	BUG_ON(atomic_read(&jl->j_commit_left) != 1);
1098 
1099 	/*
1100 	 * If there was a write error in the journal - we can't commit
1101 	 * this transaction - it will be invalid and, if successful,
1102 	 * will just end up propagating the write error out to
1103 	 * the file system.
1104 	 */
1105 	if (likely(!retval && !reiserfs_is_journal_aborted (journal))) {
1106 		if (buffer_dirty(jl->j_commit_bh))
1107 			BUG();
1108 		mark_buffer_dirty(jl->j_commit_bh) ;
1109 		depth = reiserfs_write_unlock_nested(s);
1110 		if (reiserfs_barrier_flush(s))
1111 			__sync_dirty_buffer(jl->j_commit_bh,
1112 					REQ_SYNC | REQ_PREFLUSH | REQ_FUA);
1113 		else
1114 			sync_dirty_buffer(jl->j_commit_bh);
1115 		reiserfs_write_lock_nested(s, depth);
1116 	}
1117 
1118 	/*
1119 	 * If there was a write error in the journal - we can't commit this
1120 	 * transaction - it will be invalid and, if successful, will just end
1121 	 * up propagating the write error out to the filesystem.
1122 	 */
1123 	if (unlikely(!buffer_uptodate(jl->j_commit_bh))) {
1124 #ifdef CONFIG_REISERFS_CHECK
1125 		reiserfs_warning(s, "journal-615", "buffer write failed");
1126 #endif
1127 		retval = -EIO;
1128 	}
1129 	bforget(jl->j_commit_bh);
1130 	if (journal->j_last_commit_id != 0 &&
1131 	    (jl->j_trans_id - journal->j_last_commit_id) != 1) {
1132 		reiserfs_warning(s, "clm-2200", "last commit %lu, current %lu",
1133 				 journal->j_last_commit_id, jl->j_trans_id);
1134 	}
1135 	journal->j_last_commit_id = jl->j_trans_id;
1136 
1137 	/*
1138 	 * now, every commit block is on the disk.  It is safe to allow
1139 	 * blocks freed during this transaction to be reallocated
1140 	 */
1141 	cleanup_freed_for_journal_list(s, jl);
1142 
1143 	retval = retval ? retval : journal->j_errno;
1144 
1145 	/* mark the metadata dirty */
1146 	if (!retval)
1147 		dirty_one_transaction(s, jl);
1148 	atomic_dec(&jl->j_commit_left);
1149 
1150 	if (flushall) {
1151 		atomic_set(&jl->j_older_commits_done, 1);
1152 	}
1153 	mutex_unlock(&jl->j_commit_mutex);
1154 put_jl:
1155 	put_journal_list(s, jl);
1156 
1157 	if (retval)
1158 		reiserfs_abort(s, retval, "Journal write error in %s",
1159 			       __func__);
1160 	return retval;
1161 }
1162 
1163 /*
1164  * flush_journal_list frequently needs to find a newer transaction for a
1165  * given block.  This does that, or returns NULL if it can't find anything
1166  */
1167 static struct reiserfs_journal_list *find_newer_jl_for_cn(struct
1168 							  reiserfs_journal_cnode
1169 							  *cn)
1170 {
1171 	struct super_block *sb = cn->sb;
1172 	b_blocknr_t blocknr = cn->blocknr;
1173 
1174 	cn = cn->hprev;
1175 	while (cn) {
1176 		if (cn->sb == sb && cn->blocknr == blocknr && cn->jlist) {
1177 			return cn->jlist;
1178 		}
1179 		cn = cn->hprev;
1180 	}
1181 	return NULL;
1182 }
1183 
1184 static void remove_journal_hash(struct super_block *,
1185 				struct reiserfs_journal_cnode **,
1186 				struct reiserfs_journal_list *, unsigned long,
1187 				int);
1188 
1189 /*
1190  * once all the real blocks have been flushed, it is safe to remove them
1191  * from the journal list for this transaction.  Aside from freeing the
1192  * cnode, this also allows the block to be reallocated for data blocks
1193  * if it had been deleted.
1194  */
1195 static void remove_all_from_journal_list(struct super_block *sb,
1196 					 struct reiserfs_journal_list *jl,
1197 					 int debug)
1198 {
1199 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1200 	struct reiserfs_journal_cnode *cn, *last;
1201 	cn = jl->j_realblock;
1202 
1203 	/*
1204 	 * which is better, to lock once around the whole loop, or
1205 	 * to lock for each call to remove_journal_hash?
1206 	 */
1207 	while (cn) {
1208 		if (cn->blocknr != 0) {
1209 			if (debug) {
1210 				reiserfs_warning(sb, "reiserfs-2201",
1211 						 "block %u, bh is %d, state %ld",
1212 						 cn->blocknr, cn->bh ? 1 : 0,
1213 						 cn->state);
1214 			}
1215 			cn->state = 0;
1216 			remove_journal_hash(sb, journal->j_list_hash_table,
1217 					    jl, cn->blocknr, 1);
1218 		}
1219 		last = cn;
1220 		cn = cn->next;
1221 		free_cnode(sb, last);
1222 	}
1223 	jl->j_realblock = NULL;
1224 }
1225 
1226 /*
1227  * if this timestamp is greater than the timestamp we wrote last to the
1228  * header block, write it to the header block.  once this is done, I can
1229  * safely say the log area for this transaction won't ever be replayed,
1230  * and I can start releasing blocks in this transaction for reuse as data
1231  * blocks.  called by flush_journal_list, before it calls
1232  * remove_all_from_journal_list
1233  */
1234 static int _update_journal_header_block(struct super_block *sb,
1235 					unsigned long offset,
1236 					unsigned int trans_id)
1237 {
1238 	struct reiserfs_journal_header *jh;
1239 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1240 	int depth;
1241 
1242 	if (reiserfs_is_journal_aborted(journal))
1243 		return -EIO;
1244 
1245 	if (trans_id >= journal->j_last_flush_trans_id) {
1246 		if (buffer_locked((journal->j_header_bh))) {
1247 			depth = reiserfs_write_unlock_nested(sb);
1248 			__wait_on_buffer(journal->j_header_bh);
1249 			reiserfs_write_lock_nested(sb, depth);
1250 			if (unlikely(!buffer_uptodate(journal->j_header_bh))) {
1251 #ifdef CONFIG_REISERFS_CHECK
1252 				reiserfs_warning(sb, "journal-699",
1253 						 "buffer write failed");
1254 #endif
1255 				return -EIO;
1256 			}
1257 		}
1258 		journal->j_last_flush_trans_id = trans_id;
1259 		journal->j_first_unflushed_offset = offset;
1260 		jh = (struct reiserfs_journal_header *)(journal->j_header_bh->
1261 							b_data);
1262 		jh->j_last_flush_trans_id = cpu_to_le32(trans_id);
1263 		jh->j_first_unflushed_offset = cpu_to_le32(offset);
1264 		jh->j_mount_id = cpu_to_le32(journal->j_mount_id);
1265 
1266 		set_buffer_dirty(journal->j_header_bh);
1267 		depth = reiserfs_write_unlock_nested(sb);
1268 
1269 		if (reiserfs_barrier_flush(sb))
1270 			__sync_dirty_buffer(journal->j_header_bh,
1271 					REQ_SYNC | REQ_PREFLUSH | REQ_FUA);
1272 		else
1273 			sync_dirty_buffer(journal->j_header_bh);
1274 
1275 		reiserfs_write_lock_nested(sb, depth);
1276 		if (!buffer_uptodate(journal->j_header_bh)) {
1277 			reiserfs_warning(sb, "journal-837",
1278 					 "IO error during journal replay");
1279 			return -EIO;
1280 		}
1281 	}
1282 	return 0;
1283 }
1284 
1285 static int update_journal_header_block(struct super_block *sb,
1286 				       unsigned long offset,
1287 				       unsigned int trans_id)
1288 {
1289 	return _update_journal_header_block(sb, offset, trans_id);
1290 }
1291 
1292 /*
1293 ** flush any and all journal lists older than you are
1294 ** can only be called from flush_journal_list
1295 */
1296 static int flush_older_journal_lists(struct super_block *sb,
1297 				     struct reiserfs_journal_list *jl)
1298 {
1299 	struct list_head *entry;
1300 	struct reiserfs_journal_list *other_jl;
1301 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1302 	unsigned int trans_id = jl->j_trans_id;
1303 
1304 	/*
1305 	 * we know we are the only ones flushing things, no extra race
1306 	 * protection is required.
1307 	 */
1308 restart:
1309 	entry = journal->j_journal_list.next;
1310 	/* Did we wrap? */
1311 	if (entry == &journal->j_journal_list)
1312 		return 0;
1313 	other_jl = JOURNAL_LIST_ENTRY(entry);
1314 	if (other_jl->j_trans_id < trans_id) {
1315 		BUG_ON(other_jl->j_refcount <= 0);
1316 		/* do not flush all */
1317 		flush_journal_list(sb, other_jl, 0);
1318 
1319 		/* other_jl is now deleted from the list */
1320 		goto restart;
1321 	}
1322 	return 0;
1323 }
1324 
1325 static void del_from_work_list(struct super_block *s,
1326 			       struct reiserfs_journal_list *jl)
1327 {
1328 	struct reiserfs_journal *journal = SB_JOURNAL(s);
1329 	if (!list_empty(&jl->j_working_list)) {
1330 		list_del_init(&jl->j_working_list);
1331 		journal->j_num_work_lists--;
1332 	}
1333 }
1334 
1335 /*
1336  * flush a journal list, both commit and real blocks
1337  *
1338  * always set flushall to 1, unless you are calling from inside
1339  * flush_journal_list
1340  *
1341  * IMPORTANT.  This can only be called while there are no journal writers,
1342  * and the journal is locked.  That means it can only be called from
1343  * do_journal_end, or by journal_release
1344  */
1345 static int flush_journal_list(struct super_block *s,
1346 			      struct reiserfs_journal_list *jl, int flushall)
1347 {
1348 	struct reiserfs_journal_list *pjl;
1349 	struct reiserfs_journal_cnode *cn;
1350 	int count;
1351 	int was_jwait = 0;
1352 	int was_dirty = 0;
1353 	struct buffer_head *saved_bh;
1354 	unsigned long j_len_saved = jl->j_len;
1355 	struct reiserfs_journal *journal = SB_JOURNAL(s);
1356 	int err = 0;
1357 	int depth;
1358 
1359 	BUG_ON(j_len_saved <= 0);
1360 
1361 	if (atomic_read(&journal->j_wcount) != 0) {
1362 		reiserfs_warning(s, "clm-2048", "called with wcount %d",
1363 				 atomic_read(&journal->j_wcount));
1364 	}
1365 
1366 	/* if flushall == 0, the lock is already held */
1367 	if (flushall) {
1368 		reiserfs_mutex_lock_safe(&journal->j_flush_mutex, s);
1369 	} else if (mutex_trylock(&journal->j_flush_mutex)) {
1370 		BUG();
1371 	}
1372 
1373 	count = 0;
1374 	if (j_len_saved > journal->j_trans_max) {
1375 		reiserfs_panic(s, "journal-715", "length is %lu, trans id %lu",
1376 			       j_len_saved, jl->j_trans_id);
1377 		return 0;
1378 	}
1379 
1380 	/* if all the work is already done, get out of here */
1381 	if (atomic_read(&jl->j_nonzerolen) <= 0 &&
1382 	    atomic_read(&jl->j_commit_left) <= 0) {
1383 		goto flush_older_and_return;
1384 	}
1385 
1386 	/*
1387 	 * start by putting the commit list on disk.  This will also flush
1388 	 * the commit lists of any olders transactions
1389 	 */
1390 	flush_commit_list(s, jl, 1);
1391 
1392 	if (!(jl->j_state & LIST_DIRTY)
1393 	    && !reiserfs_is_journal_aborted(journal))
1394 		BUG();
1395 
1396 	/* are we done now? */
1397 	if (atomic_read(&jl->j_nonzerolen) <= 0 &&
1398 	    atomic_read(&jl->j_commit_left) <= 0) {
1399 		goto flush_older_and_return;
1400 	}
1401 
1402 	/*
1403 	 * loop through each cnode, see if we need to write it,
1404 	 * or wait on a more recent transaction, or just ignore it
1405 	 */
1406 	if (atomic_read(&journal->j_wcount) != 0) {
1407 		reiserfs_panic(s, "journal-844", "journal list is flushing, "
1408 			       "wcount is not 0");
1409 	}
1410 	cn = jl->j_realblock;
1411 	while (cn) {
1412 		was_jwait = 0;
1413 		was_dirty = 0;
1414 		saved_bh = NULL;
1415 		/* blocknr of 0 is no longer in the hash, ignore it */
1416 		if (cn->blocknr == 0) {
1417 			goto free_cnode;
1418 		}
1419 
1420 		/*
1421 		 * This transaction failed commit.
1422 		 * Don't write out to the disk
1423 		 */
1424 		if (!(jl->j_state & LIST_DIRTY))
1425 			goto free_cnode;
1426 
1427 		pjl = find_newer_jl_for_cn(cn);
1428 		/*
1429 		 * the order is important here.  We check pjl to make sure we
1430 		 * don't clear BH_JDirty_wait if we aren't the one writing this
1431 		 * block to disk
1432 		 */
1433 		if (!pjl && cn->bh) {
1434 			saved_bh = cn->bh;
1435 
1436 			/*
1437 			 * we do this to make sure nobody releases the
1438 			 * buffer while we are working with it
1439 			 */
1440 			get_bh(saved_bh);
1441 
1442 			if (buffer_journal_dirty(saved_bh)) {
1443 				BUG_ON(!can_dirty(cn));
1444 				was_jwait = 1;
1445 				was_dirty = 1;
1446 			} else if (can_dirty(cn)) {
1447 				/*
1448 				 * everything with !pjl && jwait
1449 				 * should be writable
1450 				 */
1451 				BUG();
1452 			}
1453 		}
1454 
1455 		/*
1456 		 * if someone has this block in a newer transaction, just make
1457 		 * sure they are committed, and don't try writing it to disk
1458 		 */
1459 		if (pjl) {
1460 			if (atomic_read(&pjl->j_commit_left))
1461 				flush_commit_list(s, pjl, 1);
1462 			goto free_cnode;
1463 		}
1464 
1465 		/*
1466 		 * bh == NULL when the block got to disk on its own, OR,
1467 		 * the block got freed in a future transaction
1468 		 */
1469 		if (saved_bh == NULL) {
1470 			goto free_cnode;
1471 		}
1472 
1473 		/*
1474 		 * this should never happen.  kupdate_one_transaction has
1475 		 * this list locked while it works, so we should never see a
1476 		 * buffer here that is not marked JDirty_wait
1477 		 */
1478 		if ((!was_jwait) && !buffer_locked(saved_bh)) {
1479 			reiserfs_warning(s, "journal-813",
1480 					 "BAD! buffer %llu %cdirty %cjwait, "
1481 					 "not in a newer transaction",
1482 					 (unsigned long long)saved_bh->
1483 					 b_blocknr, was_dirty ? ' ' : '!',
1484 					 was_jwait ? ' ' : '!');
1485 		}
1486 		if (was_dirty) {
1487 			/*
1488 			 * we inc again because saved_bh gets decremented
1489 			 * at free_cnode
1490 			 */
1491 			get_bh(saved_bh);
1492 			set_bit(BLOCK_NEEDS_FLUSH, &cn->state);
1493 			lock_buffer(saved_bh);
1494 			BUG_ON(cn->blocknr != saved_bh->b_blocknr);
1495 			if (buffer_dirty(saved_bh))
1496 				submit_logged_buffer(saved_bh);
1497 			else
1498 				unlock_buffer(saved_bh);
1499 			count++;
1500 		} else {
1501 			reiserfs_warning(s, "clm-2082",
1502 					 "Unable to flush buffer %llu in %s",
1503 					 (unsigned long long)saved_bh->
1504 					 b_blocknr, __func__);
1505 		}
1506 free_cnode:
1507 		cn = cn->next;
1508 		if (saved_bh) {
1509 			/*
1510 			 * we incremented this to keep others from
1511 			 * taking the buffer head away
1512 			 */
1513 			put_bh(saved_bh);
1514 			if (atomic_read(&saved_bh->b_count) < 0) {
1515 				reiserfs_warning(s, "journal-945",
1516 						 "saved_bh->b_count < 0");
1517 			}
1518 		}
1519 	}
1520 	if (count > 0) {
1521 		cn = jl->j_realblock;
1522 		while (cn) {
1523 			if (test_bit(BLOCK_NEEDS_FLUSH, &cn->state)) {
1524 				if (!cn->bh) {
1525 					reiserfs_panic(s, "journal-1011",
1526 						       "cn->bh is NULL");
1527 				}
1528 
1529 				depth = reiserfs_write_unlock_nested(s);
1530 				__wait_on_buffer(cn->bh);
1531 				reiserfs_write_lock_nested(s, depth);
1532 
1533 				if (!cn->bh) {
1534 					reiserfs_panic(s, "journal-1012",
1535 						       "cn->bh is NULL");
1536 				}
1537 				if (unlikely(!buffer_uptodate(cn->bh))) {
1538 #ifdef CONFIG_REISERFS_CHECK
1539 					reiserfs_warning(s, "journal-949",
1540 							 "buffer write failed");
1541 #endif
1542 					err = -EIO;
1543 				}
1544 				/*
1545 				 * note, we must clear the JDirty_wait bit
1546 				 * after the up to date check, otherwise we
1547 				 * race against our flushpage routine
1548 				 */
1549 				BUG_ON(!test_clear_buffer_journal_dirty
1550 				       (cn->bh));
1551 
1552 				/* drop one ref for us */
1553 				put_bh(cn->bh);
1554 				/* drop one ref for journal_mark_dirty */
1555 				release_buffer_page(cn->bh);
1556 			}
1557 			cn = cn->next;
1558 		}
1559 	}
1560 
1561 	if (err)
1562 		reiserfs_abort(s, -EIO,
1563 			       "Write error while pushing transaction to disk in %s",
1564 			       __func__);
1565 flush_older_and_return:
1566 
1567 	/*
1568 	 * before we can update the journal header block, we _must_ flush all
1569 	 * real blocks from all older transactions to disk.  This is because
1570 	 * once the header block is updated, this transaction will not be
1571 	 * replayed after a crash
1572 	 */
1573 	if (flushall) {
1574 		flush_older_journal_lists(s, jl);
1575 	}
1576 
1577 	err = journal->j_errno;
1578 	/*
1579 	 * before we can remove everything from the hash tables for this
1580 	 * transaction, we must make sure it can never be replayed
1581 	 *
1582 	 * since we are only called from do_journal_end, we know for sure there
1583 	 * are no allocations going on while we are flushing journal lists.  So,
1584 	 * we only need to update the journal header block for the last list
1585 	 * being flushed
1586 	 */
1587 	if (!err && flushall) {
1588 		err =
1589 		    update_journal_header_block(s,
1590 						(jl->j_start + jl->j_len +
1591 						 2) % SB_ONDISK_JOURNAL_SIZE(s),
1592 						jl->j_trans_id);
1593 		if (err)
1594 			reiserfs_abort(s, -EIO,
1595 				       "Write error while updating journal header in %s",
1596 				       __func__);
1597 	}
1598 	remove_all_from_journal_list(s, jl, 0);
1599 	list_del_init(&jl->j_list);
1600 	journal->j_num_lists--;
1601 	del_from_work_list(s, jl);
1602 
1603 	if (journal->j_last_flush_id != 0 &&
1604 	    (jl->j_trans_id - journal->j_last_flush_id) != 1) {
1605 		reiserfs_warning(s, "clm-2201", "last flush %lu, current %lu",
1606 				 journal->j_last_flush_id, jl->j_trans_id);
1607 	}
1608 	journal->j_last_flush_id = jl->j_trans_id;
1609 
1610 	/*
1611 	 * not strictly required since we are freeing the list, but it should
1612 	 * help find code using dead lists later on
1613 	 */
1614 	jl->j_len = 0;
1615 	atomic_set(&jl->j_nonzerolen, 0);
1616 	jl->j_start = 0;
1617 	jl->j_realblock = NULL;
1618 	jl->j_commit_bh = NULL;
1619 	jl->j_trans_id = 0;
1620 	jl->j_state = 0;
1621 	put_journal_list(s, jl);
1622 	if (flushall)
1623 		mutex_unlock(&journal->j_flush_mutex);
1624 	return err;
1625 }
1626 
1627 static int write_one_transaction(struct super_block *s,
1628 				 struct reiserfs_journal_list *jl,
1629 				 struct buffer_chunk *chunk)
1630 {
1631 	struct reiserfs_journal_cnode *cn;
1632 	int ret = 0;
1633 
1634 	jl->j_state |= LIST_TOUCHED;
1635 	del_from_work_list(s, jl);
1636 	if (jl->j_len == 0 || atomic_read(&jl->j_nonzerolen) == 0) {
1637 		return 0;
1638 	}
1639 
1640 	cn = jl->j_realblock;
1641 	while (cn) {
1642 		/*
1643 		 * if the blocknr == 0, this has been cleared from the hash,
1644 		 * skip it
1645 		 */
1646 		if (cn->blocknr == 0) {
1647 			goto next;
1648 		}
1649 		if (cn->bh && can_dirty(cn) && buffer_dirty(cn->bh)) {
1650 			struct buffer_head *tmp_bh;
1651 			/*
1652 			 * we can race against journal_mark_freed when we try
1653 			 * to lock_buffer(cn->bh), so we have to inc the buffer
1654 			 * count, and recheck things after locking
1655 			 */
1656 			tmp_bh = cn->bh;
1657 			get_bh(tmp_bh);
1658 			lock_buffer(tmp_bh);
1659 			if (cn->bh && can_dirty(cn) && buffer_dirty(tmp_bh)) {
1660 				if (!buffer_journal_dirty(tmp_bh) ||
1661 				    buffer_journal_prepared(tmp_bh))
1662 					BUG();
1663 				add_to_chunk(chunk, tmp_bh, NULL, write_chunk);
1664 				ret++;
1665 			} else {
1666 				/* note, cn->bh might be null now */
1667 				unlock_buffer(tmp_bh);
1668 			}
1669 			put_bh(tmp_bh);
1670 		}
1671 next:
1672 		cn = cn->next;
1673 		cond_resched();
1674 	}
1675 	return ret;
1676 }
1677 
1678 /* used by flush_commit_list */
1679 static void dirty_one_transaction(struct super_block *s,
1680 				 struct reiserfs_journal_list *jl)
1681 {
1682 	struct reiserfs_journal_cnode *cn;
1683 	struct reiserfs_journal_list *pjl;
1684 
1685 	jl->j_state |= LIST_DIRTY;
1686 	cn = jl->j_realblock;
1687 	while (cn) {
1688 		/*
1689 		 * look for a more recent transaction that logged this
1690 		 * buffer.  Only the most recent transaction with a buffer in
1691 		 * it is allowed to send that buffer to disk
1692 		 */
1693 		pjl = find_newer_jl_for_cn(cn);
1694 		if (!pjl && cn->blocknr && cn->bh
1695 		    && buffer_journal_dirty(cn->bh)) {
1696 			BUG_ON(!can_dirty(cn));
1697 			/*
1698 			 * if the buffer is prepared, it will either be logged
1699 			 * or restored.  If restored, we need to make sure
1700 			 * it actually gets marked dirty
1701 			 */
1702 			clear_buffer_journal_new(cn->bh);
1703 			if (buffer_journal_prepared(cn->bh)) {
1704 				set_buffer_journal_restore_dirty(cn->bh);
1705 			} else {
1706 				set_buffer_journal_test(cn->bh);
1707 				mark_buffer_dirty(cn->bh);
1708 			}
1709 		}
1710 		cn = cn->next;
1711 	}
1712 }
1713 
1714 static int kupdate_transactions(struct super_block *s,
1715 				struct reiserfs_journal_list *jl,
1716 				struct reiserfs_journal_list **next_jl,
1717 				unsigned int *next_trans_id,
1718 				int num_blocks, int num_trans)
1719 {
1720 	int ret = 0;
1721 	int written = 0;
1722 	int transactions_flushed = 0;
1723 	unsigned int orig_trans_id = jl->j_trans_id;
1724 	struct buffer_chunk chunk;
1725 	struct list_head *entry;
1726 	struct reiserfs_journal *journal = SB_JOURNAL(s);
1727 	chunk.nr = 0;
1728 
1729 	reiserfs_mutex_lock_safe(&journal->j_flush_mutex, s);
1730 	if (!journal_list_still_alive(s, orig_trans_id)) {
1731 		goto done;
1732 	}
1733 
1734 	/*
1735 	 * we've got j_flush_mutex held, nobody is going to delete any
1736 	 * of these lists out from underneath us
1737 	 */
1738 	while ((num_trans && transactions_flushed < num_trans) ||
1739 	       (!num_trans && written < num_blocks)) {
1740 
1741 		if (jl->j_len == 0 || (jl->j_state & LIST_TOUCHED) ||
1742 		    atomic_read(&jl->j_commit_left)
1743 		    || !(jl->j_state & LIST_DIRTY)) {
1744 			del_from_work_list(s, jl);
1745 			break;
1746 		}
1747 		ret = write_one_transaction(s, jl, &chunk);
1748 
1749 		if (ret < 0)
1750 			goto done;
1751 		transactions_flushed++;
1752 		written += ret;
1753 		entry = jl->j_list.next;
1754 
1755 		/* did we wrap? */
1756 		if (entry == &journal->j_journal_list) {
1757 			break;
1758 		}
1759 		jl = JOURNAL_LIST_ENTRY(entry);
1760 
1761 		/* don't bother with older transactions */
1762 		if (jl->j_trans_id <= orig_trans_id)
1763 			break;
1764 	}
1765 	if (chunk.nr) {
1766 		write_chunk(&chunk);
1767 	}
1768 
1769 done:
1770 	mutex_unlock(&journal->j_flush_mutex);
1771 	return ret;
1772 }
1773 
1774 /*
1775  * for o_sync and fsync heavy applications, they tend to use
1776  * all the journa list slots with tiny transactions.  These
1777  * trigger lots and lots of calls to update the header block, which
1778  * adds seeks and slows things down.
1779  *
1780  * This function tries to clear out a large chunk of the journal lists
1781  * at once, which makes everything faster since only the newest journal
1782  * list updates the header block
1783  */
1784 static int flush_used_journal_lists(struct super_block *s,
1785 				    struct reiserfs_journal_list *jl)
1786 {
1787 	unsigned long len = 0;
1788 	unsigned long cur_len;
1789 	int i;
1790 	int limit = 256;
1791 	struct reiserfs_journal_list *tjl;
1792 	struct reiserfs_journal_list *flush_jl;
1793 	unsigned int trans_id;
1794 	struct reiserfs_journal *journal = SB_JOURNAL(s);
1795 
1796 	flush_jl = tjl = jl;
1797 
1798 	/* in data logging mode, try harder to flush a lot of blocks */
1799 	if (reiserfs_data_log(s))
1800 		limit = 1024;
1801 	/* flush for 256 transactions or limit blocks, whichever comes first */
1802 	for (i = 0; i < 256 && len < limit; i++) {
1803 		if (atomic_read(&tjl->j_commit_left) ||
1804 		    tjl->j_trans_id < jl->j_trans_id) {
1805 			break;
1806 		}
1807 		cur_len = atomic_read(&tjl->j_nonzerolen);
1808 		if (cur_len > 0) {
1809 			tjl->j_state &= ~LIST_TOUCHED;
1810 		}
1811 		len += cur_len;
1812 		flush_jl = tjl;
1813 		if (tjl->j_list.next == &journal->j_journal_list)
1814 			break;
1815 		tjl = JOURNAL_LIST_ENTRY(tjl->j_list.next);
1816 	}
1817 	get_journal_list(jl);
1818 	get_journal_list(flush_jl);
1819 
1820 	/*
1821 	 * try to find a group of blocks we can flush across all the
1822 	 * transactions, but only bother if we've actually spanned
1823 	 * across multiple lists
1824 	 */
1825 	if (flush_jl != jl)
1826 		kupdate_transactions(s, jl, &tjl, &trans_id, len, i);
1827 
1828 	flush_journal_list(s, flush_jl, 1);
1829 	put_journal_list(s, flush_jl);
1830 	put_journal_list(s, jl);
1831 	return 0;
1832 }
1833 
1834 /*
1835  * removes any nodes in table with name block and dev as bh.
1836  * only touchs the hnext and hprev pointers.
1837  */
1838 static void remove_journal_hash(struct super_block *sb,
1839 			 struct reiserfs_journal_cnode **table,
1840 			 struct reiserfs_journal_list *jl,
1841 			 unsigned long block, int remove_freed)
1842 {
1843 	struct reiserfs_journal_cnode *cur;
1844 	struct reiserfs_journal_cnode **head;
1845 
1846 	head = &(journal_hash(table, sb, block));
1847 	if (!head) {
1848 		return;
1849 	}
1850 	cur = *head;
1851 	while (cur) {
1852 		if (cur->blocknr == block && cur->sb == sb
1853 		    && (jl == NULL || jl == cur->jlist)
1854 		    && (!test_bit(BLOCK_FREED, &cur->state) || remove_freed)) {
1855 			if (cur->hnext) {
1856 				cur->hnext->hprev = cur->hprev;
1857 			}
1858 			if (cur->hprev) {
1859 				cur->hprev->hnext = cur->hnext;
1860 			} else {
1861 				*head = cur->hnext;
1862 			}
1863 			cur->blocknr = 0;
1864 			cur->sb = NULL;
1865 			cur->state = 0;
1866 			/*
1867 			 * anybody who clears the cur->bh will also
1868 			 * dec the nonzerolen
1869 			 */
1870 			if (cur->bh && cur->jlist)
1871 				atomic_dec(&cur->jlist->j_nonzerolen);
1872 			cur->bh = NULL;
1873 			cur->jlist = NULL;
1874 		}
1875 		cur = cur->hnext;
1876 	}
1877 }
1878 
1879 static void free_journal_ram(struct super_block *sb)
1880 {
1881 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1882 	kfree(journal->j_current_jl);
1883 	journal->j_num_lists--;
1884 
1885 	vfree(journal->j_cnode_free_orig);
1886 	free_list_bitmaps(sb, journal->j_list_bitmap);
1887 	free_bitmap_nodes(sb);	/* must be after free_list_bitmaps */
1888 	if (journal->j_header_bh) {
1889 		brelse(journal->j_header_bh);
1890 	}
1891 	/*
1892 	 * j_header_bh is on the journal dev, make sure
1893 	 * not to release the journal dev until we brelse j_header_bh
1894 	 */
1895 	release_journal_dev(journal);
1896 	vfree(journal);
1897 }
1898 
1899 /*
1900  * call on unmount.  Only set error to 1 if you haven't made your way out
1901  * of read_super() yet.  Any other caller must keep error at 0.
1902  */
1903 static int do_journal_release(struct reiserfs_transaction_handle *th,
1904 			      struct super_block *sb, int error)
1905 {
1906 	struct reiserfs_transaction_handle myth;
1907 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1908 
1909 	/*
1910 	 * we only want to flush out transactions if we were
1911 	 * called with error == 0
1912 	 */
1913 	if (!error && !sb_rdonly(sb)) {
1914 		/* end the current trans */
1915 		BUG_ON(!th->t_trans_id);
1916 		do_journal_end(th, FLUSH_ALL);
1917 
1918 		/*
1919 		 * make sure something gets logged to force
1920 		 * our way into the flush code
1921 		 */
1922 		if (!journal_join(&myth, sb)) {
1923 			reiserfs_prepare_for_journal(sb,
1924 						     SB_BUFFER_WITH_SB(sb),
1925 						     1);
1926 			journal_mark_dirty(&myth, SB_BUFFER_WITH_SB(sb));
1927 			do_journal_end(&myth, FLUSH_ALL);
1928 		}
1929 	}
1930 
1931 	/* this also catches errors during the do_journal_end above */
1932 	if (!error && reiserfs_is_journal_aborted(journal)) {
1933 		memset(&myth, 0, sizeof(myth));
1934 		if (!journal_join_abort(&myth, sb)) {
1935 			reiserfs_prepare_for_journal(sb,
1936 						     SB_BUFFER_WITH_SB(sb),
1937 						     1);
1938 			journal_mark_dirty(&myth, SB_BUFFER_WITH_SB(sb));
1939 			do_journal_end(&myth, FLUSH_ALL);
1940 		}
1941 	}
1942 
1943 
1944 	/*
1945 	 * We must release the write lock here because
1946 	 * the workqueue job (flush_async_commit) needs this lock
1947 	 */
1948 	reiserfs_write_unlock(sb);
1949 
1950 	/*
1951 	 * Cancel flushing of old commits. Note that neither of these works
1952 	 * will be requeued because superblock is being shutdown and doesn't
1953 	 * have SB_ACTIVE set.
1954 	 */
1955 	reiserfs_cancel_old_flush(sb);
1956 	/* wait for all commits to finish */
1957 	cancel_delayed_work_sync(&SB_JOURNAL(sb)->j_work);
1958 
1959 	free_journal_ram(sb);
1960 
1961 	reiserfs_write_lock(sb);
1962 
1963 	return 0;
1964 }
1965 
1966 /* * call on unmount.  flush all journal trans, release all alloc'd ram */
1967 int journal_release(struct reiserfs_transaction_handle *th,
1968 		    struct super_block *sb)
1969 {
1970 	return do_journal_release(th, sb, 0);
1971 }
1972 
1973 /* only call from an error condition inside reiserfs_read_super!  */
1974 int journal_release_error(struct reiserfs_transaction_handle *th,
1975 			  struct super_block *sb)
1976 {
1977 	return do_journal_release(th, sb, 1);
1978 }
1979 
1980 /*
1981  * compares description block with commit block.
1982  * returns 1 if they differ, 0 if they are the same
1983  */
1984 static int journal_compare_desc_commit(struct super_block *sb,
1985 				       struct reiserfs_journal_desc *desc,
1986 				       struct reiserfs_journal_commit *commit)
1987 {
1988 	if (get_commit_trans_id(commit) != get_desc_trans_id(desc) ||
1989 	    get_commit_trans_len(commit) != get_desc_trans_len(desc) ||
1990 	    get_commit_trans_len(commit) > SB_JOURNAL(sb)->j_trans_max ||
1991 	    get_commit_trans_len(commit) <= 0) {
1992 		return 1;
1993 	}
1994 	return 0;
1995 }
1996 
1997 /*
1998  * returns 0 if it did not find a description block
1999  * returns -1 if it found a corrupt commit block
2000  * returns 1 if both desc and commit were valid
2001  * NOTE: only called during fs mount
2002  */
2003 static int journal_transaction_is_valid(struct super_block *sb,
2004 					struct buffer_head *d_bh,
2005 					unsigned int *oldest_invalid_trans_id,
2006 					unsigned long *newest_mount_id)
2007 {
2008 	struct reiserfs_journal_desc *desc;
2009 	struct reiserfs_journal_commit *commit;
2010 	struct buffer_head *c_bh;
2011 	unsigned long offset;
2012 
2013 	if (!d_bh)
2014 		return 0;
2015 
2016 	desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2017 	if (get_desc_trans_len(desc) > 0
2018 	    && !memcmp(get_journal_desc_magic(d_bh), JOURNAL_DESC_MAGIC, 8)) {
2019 		if (oldest_invalid_trans_id && *oldest_invalid_trans_id
2020 		    && get_desc_trans_id(desc) > *oldest_invalid_trans_id) {
2021 			reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2022 				       "journal-986: transaction "
2023 				       "is valid returning because trans_id %d is greater than "
2024 				       "oldest_invalid %lu",
2025 				       get_desc_trans_id(desc),
2026 				       *oldest_invalid_trans_id);
2027 			return 0;
2028 		}
2029 		if (newest_mount_id
2030 		    && *newest_mount_id > get_desc_mount_id(desc)) {
2031 			reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2032 				       "journal-1087: transaction "
2033 				       "is valid returning because mount_id %d is less than "
2034 				       "newest_mount_id %lu",
2035 				       get_desc_mount_id(desc),
2036 				       *newest_mount_id);
2037 			return -1;
2038 		}
2039 		if (get_desc_trans_len(desc) > SB_JOURNAL(sb)->j_trans_max) {
2040 			reiserfs_warning(sb, "journal-2018",
2041 					 "Bad transaction length %d "
2042 					 "encountered, ignoring transaction",
2043 					 get_desc_trans_len(desc));
2044 			return -1;
2045 		}
2046 		offset = d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2047 
2048 		/*
2049 		 * ok, we have a journal description block,
2050 		 * let's see if the transaction was valid
2051 		 */
2052 		c_bh =
2053 		    journal_bread(sb,
2054 				  SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2055 				  ((offset + get_desc_trans_len(desc) +
2056 				    1) % SB_ONDISK_JOURNAL_SIZE(sb)));
2057 		if (!c_bh)
2058 			return 0;
2059 		commit = (struct reiserfs_journal_commit *)c_bh->b_data;
2060 		if (journal_compare_desc_commit(sb, desc, commit)) {
2061 			reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2062 				       "journal_transaction_is_valid, commit offset %ld had bad "
2063 				       "time %d or length %d",
2064 				       c_bh->b_blocknr -
2065 				       SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2066 				       get_commit_trans_id(commit),
2067 				       get_commit_trans_len(commit));
2068 			brelse(c_bh);
2069 			if (oldest_invalid_trans_id) {
2070 				*oldest_invalid_trans_id =
2071 				    get_desc_trans_id(desc);
2072 				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2073 					       "journal-1004: "
2074 					       "transaction_is_valid setting oldest invalid trans_id "
2075 					       "to %d",
2076 					       get_desc_trans_id(desc));
2077 			}
2078 			return -1;
2079 		}
2080 		brelse(c_bh);
2081 		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2082 			       "journal-1006: found valid "
2083 			       "transaction start offset %llu, len %d id %d",
2084 			       d_bh->b_blocknr -
2085 			       SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2086 			       get_desc_trans_len(desc),
2087 			       get_desc_trans_id(desc));
2088 		return 1;
2089 	} else {
2090 		return 0;
2091 	}
2092 }
2093 
2094 static void brelse_array(struct buffer_head **heads, int num)
2095 {
2096 	int i;
2097 	for (i = 0; i < num; i++) {
2098 		brelse(heads[i]);
2099 	}
2100 }
2101 
2102 /*
2103  * given the start, and values for the oldest acceptable transactions,
2104  * this either reads in a replays a transaction, or returns because the
2105  * transaction is invalid, or too old.
2106  * NOTE: only called during fs mount
2107  */
2108 static int journal_read_transaction(struct super_block *sb,
2109 				    unsigned long cur_dblock,
2110 				    unsigned long oldest_start,
2111 				    unsigned int oldest_trans_id,
2112 				    unsigned long newest_mount_id)
2113 {
2114 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
2115 	struct reiserfs_journal_desc *desc;
2116 	struct reiserfs_journal_commit *commit;
2117 	unsigned int trans_id = 0;
2118 	struct buffer_head *c_bh;
2119 	struct buffer_head *d_bh;
2120 	struct buffer_head **log_blocks = NULL;
2121 	struct buffer_head **real_blocks = NULL;
2122 	unsigned int trans_offset;
2123 	int i;
2124 	int trans_half;
2125 
2126 	d_bh = journal_bread(sb, cur_dblock);
2127 	if (!d_bh)
2128 		return 1;
2129 	desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2130 	trans_offset = d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2131 	reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1037: "
2132 		       "journal_read_transaction, offset %llu, len %d mount_id %d",
2133 		       d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2134 		       get_desc_trans_len(desc), get_desc_mount_id(desc));
2135 	if (get_desc_trans_id(desc) < oldest_trans_id) {
2136 		reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1039: "
2137 			       "journal_read_trans skipping because %lu is too old",
2138 			       cur_dblock -
2139 			       SB_ONDISK_JOURNAL_1st_BLOCK(sb));
2140 		brelse(d_bh);
2141 		return 1;
2142 	}
2143 	if (get_desc_mount_id(desc) != newest_mount_id) {
2144 		reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1146: "
2145 			       "journal_read_trans skipping because %d is != "
2146 			       "newest_mount_id %lu", get_desc_mount_id(desc),
2147 			       newest_mount_id);
2148 		brelse(d_bh);
2149 		return 1;
2150 	}
2151 	c_bh = journal_bread(sb, SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2152 			     ((trans_offset + get_desc_trans_len(desc) + 1) %
2153 			      SB_ONDISK_JOURNAL_SIZE(sb)));
2154 	if (!c_bh) {
2155 		brelse(d_bh);
2156 		return 1;
2157 	}
2158 	commit = (struct reiserfs_journal_commit *)c_bh->b_data;
2159 	if (journal_compare_desc_commit(sb, desc, commit)) {
2160 		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2161 			       "journal_read_transaction, "
2162 			       "commit offset %llu had bad time %d or length %d",
2163 			       c_bh->b_blocknr -
2164 			       SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2165 			       get_commit_trans_id(commit),
2166 			       get_commit_trans_len(commit));
2167 		brelse(c_bh);
2168 		brelse(d_bh);
2169 		return 1;
2170 	}
2171 
2172 	if (bdev_read_only(sb->s_bdev)) {
2173 		reiserfs_warning(sb, "clm-2076",
2174 				 "device is readonly, unable to replay log");
2175 		brelse(c_bh);
2176 		brelse(d_bh);
2177 		return -EROFS;
2178 	}
2179 
2180 	trans_id = get_desc_trans_id(desc);
2181 	/*
2182 	 * now we know we've got a good transaction, and it was
2183 	 * inside the valid time ranges
2184 	 */
2185 	log_blocks = kmalloc_array(get_desc_trans_len(desc),
2186 				   sizeof(struct buffer_head *),
2187 				   GFP_NOFS);
2188 	real_blocks = kmalloc_array(get_desc_trans_len(desc),
2189 				    sizeof(struct buffer_head *),
2190 				    GFP_NOFS);
2191 	if (!log_blocks || !real_blocks) {
2192 		brelse(c_bh);
2193 		brelse(d_bh);
2194 		kfree(log_blocks);
2195 		kfree(real_blocks);
2196 		reiserfs_warning(sb, "journal-1169",
2197 				 "kmalloc failed, unable to mount FS");
2198 		return -1;
2199 	}
2200 	/* get all the buffer heads */
2201 	trans_half = journal_trans_half(sb->s_blocksize);
2202 	for (i = 0; i < get_desc_trans_len(desc); i++) {
2203 		log_blocks[i] =
2204 		    journal_getblk(sb,
2205 				   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2206 				   (trans_offset + 1 +
2207 				    i) % SB_ONDISK_JOURNAL_SIZE(sb));
2208 		if (i < trans_half) {
2209 			real_blocks[i] =
2210 			    sb_getblk(sb,
2211 				      le32_to_cpu(desc->j_realblock[i]));
2212 		} else {
2213 			real_blocks[i] =
2214 			    sb_getblk(sb,
2215 				      le32_to_cpu(commit->
2216 						  j_realblock[i - trans_half]));
2217 		}
2218 		if (real_blocks[i]->b_blocknr > SB_BLOCK_COUNT(sb)) {
2219 			reiserfs_warning(sb, "journal-1207",
2220 					 "REPLAY FAILURE fsck required! "
2221 					 "Block to replay is outside of "
2222 					 "filesystem");
2223 			goto abort_replay;
2224 		}
2225 		/* make sure we don't try to replay onto log or reserved area */
2226 		if (is_block_in_log_or_reserved_area
2227 		    (sb, real_blocks[i]->b_blocknr)) {
2228 			reiserfs_warning(sb, "journal-1204",
2229 					 "REPLAY FAILURE fsck required! "
2230 					 "Trying to replay onto a log block");
2231 abort_replay:
2232 			brelse_array(log_blocks, i);
2233 			brelse_array(real_blocks, i);
2234 			brelse(c_bh);
2235 			brelse(d_bh);
2236 			kfree(log_blocks);
2237 			kfree(real_blocks);
2238 			return -1;
2239 		}
2240 	}
2241 	/* read in the log blocks, memcpy to the corresponding real block */
2242 	bh_read_batch(get_desc_trans_len(desc), log_blocks);
2243 	for (i = 0; i < get_desc_trans_len(desc); i++) {
2244 
2245 		wait_on_buffer(log_blocks[i]);
2246 		if (!buffer_uptodate(log_blocks[i])) {
2247 			reiserfs_warning(sb, "journal-1212",
2248 					 "REPLAY FAILURE fsck required! "
2249 					 "buffer write failed");
2250 			brelse_array(log_blocks + i,
2251 				     get_desc_trans_len(desc) - i);
2252 			brelse_array(real_blocks, get_desc_trans_len(desc));
2253 			brelse(c_bh);
2254 			brelse(d_bh);
2255 			kfree(log_blocks);
2256 			kfree(real_blocks);
2257 			return -1;
2258 		}
2259 		memcpy(real_blocks[i]->b_data, log_blocks[i]->b_data,
2260 		       real_blocks[i]->b_size);
2261 		set_buffer_uptodate(real_blocks[i]);
2262 		brelse(log_blocks[i]);
2263 	}
2264 	/* flush out the real blocks */
2265 	for (i = 0; i < get_desc_trans_len(desc); i++) {
2266 		set_buffer_dirty(real_blocks[i]);
2267 		write_dirty_buffer(real_blocks[i], 0);
2268 	}
2269 	for (i = 0; i < get_desc_trans_len(desc); i++) {
2270 		wait_on_buffer(real_blocks[i]);
2271 		if (!buffer_uptodate(real_blocks[i])) {
2272 			reiserfs_warning(sb, "journal-1226",
2273 					 "REPLAY FAILURE, fsck required! "
2274 					 "buffer write failed");
2275 			brelse_array(real_blocks + i,
2276 				     get_desc_trans_len(desc) - i);
2277 			brelse(c_bh);
2278 			brelse(d_bh);
2279 			kfree(log_blocks);
2280 			kfree(real_blocks);
2281 			return -1;
2282 		}
2283 		brelse(real_blocks[i]);
2284 	}
2285 	cur_dblock =
2286 	    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2287 	    ((trans_offset + get_desc_trans_len(desc) +
2288 	      2) % SB_ONDISK_JOURNAL_SIZE(sb));
2289 	reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2290 		       "journal-1095: setting journal " "start to offset %ld",
2291 		       cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb));
2292 
2293 	/*
2294 	 * init starting values for the first transaction, in case
2295 	 * this is the last transaction to be replayed.
2296 	 */
2297 	journal->j_start = cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2298 	journal->j_last_flush_trans_id = trans_id;
2299 	journal->j_trans_id = trans_id + 1;
2300 	/* check for trans_id overflow */
2301 	if (journal->j_trans_id == 0)
2302 		journal->j_trans_id = 10;
2303 	brelse(c_bh);
2304 	brelse(d_bh);
2305 	kfree(log_blocks);
2306 	kfree(real_blocks);
2307 	return 0;
2308 }
2309 
2310 /*
2311  * This function reads blocks starting from block and to max_block of bufsize
2312  * size (but no more than BUFNR blocks at a time). This proved to improve
2313  * mounting speed on self-rebuilding raid5 arrays at least.
2314  * Right now it is only used from journal code. But later we might use it
2315  * from other places.
2316  * Note: Do not use journal_getblk/sb_getblk functions here!
2317  */
2318 static struct buffer_head *reiserfs_breada(struct block_device *dev,
2319 					   b_blocknr_t block, int bufsize,
2320 					   b_blocknr_t max_block)
2321 {
2322 	struct buffer_head *bhlist[BUFNR];
2323 	unsigned int blocks = BUFNR;
2324 	struct buffer_head *bh;
2325 	int i, j;
2326 
2327 	bh = __getblk(dev, block, bufsize);
2328 	if (!bh || buffer_uptodate(bh))
2329 		return (bh);
2330 
2331 	if (block + BUFNR > max_block) {
2332 		blocks = max_block - block;
2333 	}
2334 	bhlist[0] = bh;
2335 	j = 1;
2336 	for (i = 1; i < blocks; i++) {
2337 		bh = __getblk(dev, block + i, bufsize);
2338 		if (!bh)
2339 			break;
2340 		if (buffer_uptodate(bh)) {
2341 			brelse(bh);
2342 			break;
2343 		} else
2344 			bhlist[j++] = bh;
2345 	}
2346 	bh = bhlist[0];
2347 	bh_read_nowait(bh, 0);
2348 	bh_readahead_batch(j - 1, &bhlist[1], 0);
2349 	for (i = 1; i < j; i++)
2350 		brelse(bhlist[i]);
2351 	wait_on_buffer(bh);
2352 	if (buffer_uptodate(bh))
2353 		return bh;
2354 	brelse(bh);
2355 	return NULL;
2356 }
2357 
2358 /*
2359  * read and replay the log
2360  * on a clean unmount, the journal header's next unflushed pointer will be
2361  * to an invalid transaction.  This tests that before finding all the
2362  * transactions in the log, which makes normal mount times fast.
2363  *
2364  * After a crash, this starts with the next unflushed transaction, and
2365  * replays until it finds one too old, or invalid.
2366  *
2367  * On exit, it sets things up so the first transaction will work correctly.
2368  * NOTE: only called during fs mount
2369  */
2370 static int journal_read(struct super_block *sb)
2371 {
2372 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
2373 	struct reiserfs_journal_desc *desc;
2374 	unsigned int oldest_trans_id = 0;
2375 	unsigned int oldest_invalid_trans_id = 0;
2376 	time64_t start;
2377 	unsigned long oldest_start = 0;
2378 	unsigned long cur_dblock = 0;
2379 	unsigned long newest_mount_id = 9;
2380 	struct buffer_head *d_bh;
2381 	struct reiserfs_journal_header *jh;
2382 	int valid_journal_header = 0;
2383 	int replay_count = 0;
2384 	int continue_replay = 1;
2385 	int ret;
2386 
2387 	cur_dblock = SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2388 	reiserfs_info(sb, "checking transaction log (%pg)\n",
2389 		      file_bdev(journal->j_bdev_file));
2390 	start = ktime_get_seconds();
2391 
2392 	/*
2393 	 * step 1, read in the journal header block.  Check the transaction
2394 	 * it says is the first unflushed, and if that transaction is not
2395 	 * valid, replay is done
2396 	 */
2397 	journal->j_header_bh = journal_bread(sb,
2398 					     SB_ONDISK_JOURNAL_1st_BLOCK(sb)
2399 					     + SB_ONDISK_JOURNAL_SIZE(sb));
2400 	if (!journal->j_header_bh) {
2401 		return 1;
2402 	}
2403 	jh = (struct reiserfs_journal_header *)(journal->j_header_bh->b_data);
2404 	if (le32_to_cpu(jh->j_first_unflushed_offset) <
2405 	    SB_ONDISK_JOURNAL_SIZE(sb)
2406 	    && le32_to_cpu(jh->j_last_flush_trans_id) > 0) {
2407 		oldest_start =
2408 		    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2409 		    le32_to_cpu(jh->j_first_unflushed_offset);
2410 		oldest_trans_id = le32_to_cpu(jh->j_last_flush_trans_id) + 1;
2411 		newest_mount_id = le32_to_cpu(jh->j_mount_id);
2412 		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2413 			       "journal-1153: found in "
2414 			       "header: first_unflushed_offset %d, last_flushed_trans_id "
2415 			       "%lu", le32_to_cpu(jh->j_first_unflushed_offset),
2416 			       le32_to_cpu(jh->j_last_flush_trans_id));
2417 		valid_journal_header = 1;
2418 
2419 		/*
2420 		 * now, we try to read the first unflushed offset.  If it
2421 		 * is not valid, there is nothing more we can do, and it
2422 		 * makes no sense to read through the whole log.
2423 		 */
2424 		d_bh =
2425 		    journal_bread(sb,
2426 				  SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2427 				  le32_to_cpu(jh->j_first_unflushed_offset));
2428 		ret = journal_transaction_is_valid(sb, d_bh, NULL, NULL);
2429 		if (!ret) {
2430 			continue_replay = 0;
2431 		}
2432 		brelse(d_bh);
2433 		goto start_log_replay;
2434 	}
2435 
2436 	/*
2437 	 * ok, there are transactions that need to be replayed.  start
2438 	 * with the first log block, find all the valid transactions, and
2439 	 * pick out the oldest.
2440 	 */
2441 	while (continue_replay
2442 	       && cur_dblock <
2443 	       (SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2444 		SB_ONDISK_JOURNAL_SIZE(sb))) {
2445 		/*
2446 		 * Note that it is required for blocksize of primary fs
2447 		 * device and journal device to be the same
2448 		 */
2449 		d_bh =
2450 		    reiserfs_breada(file_bdev(journal->j_bdev_file), cur_dblock,
2451 				    sb->s_blocksize,
2452 				    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2453 				    SB_ONDISK_JOURNAL_SIZE(sb));
2454 		ret =
2455 		    journal_transaction_is_valid(sb, d_bh,
2456 						 &oldest_invalid_trans_id,
2457 						 &newest_mount_id);
2458 		if (ret == 1) {
2459 			desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2460 			if (oldest_start == 0) {	/* init all oldest_ values */
2461 				oldest_trans_id = get_desc_trans_id(desc);
2462 				oldest_start = d_bh->b_blocknr;
2463 				newest_mount_id = get_desc_mount_id(desc);
2464 				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2465 					       "journal-1179: Setting "
2466 					       "oldest_start to offset %llu, trans_id %lu",
2467 					       oldest_start -
2468 					       SB_ONDISK_JOURNAL_1st_BLOCK
2469 					       (sb), oldest_trans_id);
2470 			} else if (oldest_trans_id > get_desc_trans_id(desc)) {
2471 				/* one we just read was older */
2472 				oldest_trans_id = get_desc_trans_id(desc);
2473 				oldest_start = d_bh->b_blocknr;
2474 				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2475 					       "journal-1180: Resetting "
2476 					       "oldest_start to offset %lu, trans_id %lu",
2477 					       oldest_start -
2478 					       SB_ONDISK_JOURNAL_1st_BLOCK
2479 					       (sb), oldest_trans_id);
2480 			}
2481 			if (newest_mount_id < get_desc_mount_id(desc)) {
2482 				newest_mount_id = get_desc_mount_id(desc);
2483 				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2484 					       "journal-1299: Setting "
2485 					       "newest_mount_id to %d",
2486 					       get_desc_mount_id(desc));
2487 			}
2488 			cur_dblock += get_desc_trans_len(desc) + 2;
2489 		} else {
2490 			cur_dblock++;
2491 		}
2492 		brelse(d_bh);
2493 	}
2494 
2495 start_log_replay:
2496 	cur_dblock = oldest_start;
2497 	if (oldest_trans_id) {
2498 		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2499 			       "journal-1206: Starting replay "
2500 			       "from offset %llu, trans_id %lu",
2501 			       cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2502 			       oldest_trans_id);
2503 
2504 	}
2505 	replay_count = 0;
2506 	while (continue_replay && oldest_trans_id > 0) {
2507 		ret =
2508 		    journal_read_transaction(sb, cur_dblock, oldest_start,
2509 					     oldest_trans_id, newest_mount_id);
2510 		if (ret < 0) {
2511 			return ret;
2512 		} else if (ret != 0) {
2513 			break;
2514 		}
2515 		cur_dblock =
2516 		    SB_ONDISK_JOURNAL_1st_BLOCK(sb) + journal->j_start;
2517 		replay_count++;
2518 		if (cur_dblock == oldest_start)
2519 			break;
2520 	}
2521 
2522 	if (oldest_trans_id == 0) {
2523 		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2524 			       "journal-1225: No valid " "transactions found");
2525 	}
2526 	/*
2527 	 * j_start does not get set correctly if we don't replay any
2528 	 * transactions.  if we had a valid journal_header, set j_start
2529 	 * to the first unflushed transaction value, copy the trans_id
2530 	 * from the header
2531 	 */
2532 	if (valid_journal_header && replay_count == 0) {
2533 		journal->j_start = le32_to_cpu(jh->j_first_unflushed_offset);
2534 		journal->j_trans_id =
2535 		    le32_to_cpu(jh->j_last_flush_trans_id) + 1;
2536 		/* check for trans_id overflow */
2537 		if (journal->j_trans_id == 0)
2538 			journal->j_trans_id = 10;
2539 		journal->j_last_flush_trans_id =
2540 		    le32_to_cpu(jh->j_last_flush_trans_id);
2541 		journal->j_mount_id = le32_to_cpu(jh->j_mount_id) + 1;
2542 	} else {
2543 		journal->j_mount_id = newest_mount_id + 1;
2544 	}
2545 	reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1299: Setting "
2546 		       "newest_mount_id to %lu", journal->j_mount_id);
2547 	journal->j_first_unflushed_offset = journal->j_start;
2548 	if (replay_count > 0) {
2549 		reiserfs_info(sb,
2550 			      "replayed %d transactions in %lu seconds\n",
2551 			      replay_count, ktime_get_seconds() - start);
2552 	}
2553 	/* needed to satisfy the locking in _update_journal_header_block */
2554 	reiserfs_write_lock(sb);
2555 	if (!bdev_read_only(sb->s_bdev) &&
2556 	    _update_journal_header_block(sb, journal->j_start,
2557 					 journal->j_last_flush_trans_id)) {
2558 		reiserfs_write_unlock(sb);
2559 		/*
2560 		 * replay failed, caller must call free_journal_ram and abort
2561 		 * the mount
2562 		 */
2563 		return -1;
2564 	}
2565 	reiserfs_write_unlock(sb);
2566 	return 0;
2567 }
2568 
2569 static struct reiserfs_journal_list *alloc_journal_list(struct super_block *s)
2570 {
2571 	struct reiserfs_journal_list *jl;
2572 	jl = kzalloc(sizeof(struct reiserfs_journal_list),
2573 		     GFP_NOFS | __GFP_NOFAIL);
2574 	INIT_LIST_HEAD(&jl->j_list);
2575 	INIT_LIST_HEAD(&jl->j_working_list);
2576 	INIT_LIST_HEAD(&jl->j_tail_bh_list);
2577 	INIT_LIST_HEAD(&jl->j_bh_list);
2578 	mutex_init(&jl->j_commit_mutex);
2579 	SB_JOURNAL(s)->j_num_lists++;
2580 	get_journal_list(jl);
2581 	return jl;
2582 }
2583 
2584 static void journal_list_init(struct super_block *sb)
2585 {
2586 	SB_JOURNAL(sb)->j_current_jl = alloc_journal_list(sb);
2587 }
2588 
2589 static void release_journal_dev(struct reiserfs_journal *journal)
2590 {
2591 	if (journal->j_bdev_file) {
2592 		bdev_fput(journal->j_bdev_file);
2593 		journal->j_bdev_file = NULL;
2594 	}
2595 }
2596 
2597 static int journal_init_dev(struct super_block *super,
2598 			    struct reiserfs_journal *journal,
2599 			    const char *jdev_name)
2600 {
2601 	blk_mode_t blkdev_mode = BLK_OPEN_READ;
2602 	void *holder = journal;
2603 	int result;
2604 	dev_t jdev;
2605 
2606 	result = 0;
2607 
2608 	journal->j_bdev_file = NULL;
2609 	jdev = SB_ONDISK_JOURNAL_DEVICE(super) ?
2610 	    new_decode_dev(SB_ONDISK_JOURNAL_DEVICE(super)) : super->s_dev;
2611 
2612 	if (!bdev_read_only(super->s_bdev))
2613 		blkdev_mode |= BLK_OPEN_WRITE;
2614 
2615 	/* there is no "jdev" option and journal is on separate device */
2616 	if ((!jdev_name || !jdev_name[0])) {
2617 		if (jdev == super->s_dev)
2618 			holder = NULL;
2619 		journal->j_bdev_file = bdev_file_open_by_dev(jdev, blkdev_mode,
2620 							  holder, NULL);
2621 		if (IS_ERR(journal->j_bdev_file)) {
2622 			result = PTR_ERR(journal->j_bdev_file);
2623 			journal->j_bdev_file = NULL;
2624 			reiserfs_warning(super, "sh-458",
2625 					 "cannot init journal device unknown-block(%u,%u): %i",
2626 					 MAJOR(jdev), MINOR(jdev), result);
2627 			return result;
2628 		} else if (jdev != super->s_dev)
2629 			set_blocksize(file_bdev(journal->j_bdev_file),
2630 				      super->s_blocksize);
2631 
2632 		return 0;
2633 	}
2634 
2635 	journal->j_bdev_file = bdev_file_open_by_path(jdev_name, blkdev_mode,
2636 						   holder, NULL);
2637 	if (IS_ERR(journal->j_bdev_file)) {
2638 		result = PTR_ERR(journal->j_bdev_file);
2639 		journal->j_bdev_file = NULL;
2640 		reiserfs_warning(super, "sh-457",
2641 				 "journal_init_dev: Cannot open '%s': %i",
2642 				 jdev_name, result);
2643 		return result;
2644 	}
2645 
2646 	set_blocksize(file_bdev(journal->j_bdev_file), super->s_blocksize);
2647 	reiserfs_info(super,
2648 		      "journal_init_dev: journal device: %pg\n",
2649 		      file_bdev(journal->j_bdev_file));
2650 	return 0;
2651 }
2652 
2653 /*
2654  * When creating/tuning a file system user can assign some
2655  * journal params within boundaries which depend on the ratio
2656  * blocksize/standard_blocksize.
2657  *
2658  * For blocks >= standard_blocksize transaction size should
2659  * be not less then JOURNAL_TRANS_MIN_DEFAULT, and not more
2660  * then JOURNAL_TRANS_MAX_DEFAULT.
2661  *
2662  * For blocks < standard_blocksize these boundaries should be
2663  * decreased proportionally.
2664  */
2665 #define REISERFS_STANDARD_BLKSIZE (4096)
2666 
2667 static int check_advise_trans_params(struct super_block *sb,
2668 				     struct reiserfs_journal *journal)
2669 {
2670         if (journal->j_trans_max) {
2671 		/* Non-default journal params.  Do sanity check for them. */
2672 	        int ratio = 1;
2673 		if (sb->s_blocksize < REISERFS_STANDARD_BLKSIZE)
2674 		        ratio = REISERFS_STANDARD_BLKSIZE / sb->s_blocksize;
2675 
2676 		if (journal->j_trans_max > JOURNAL_TRANS_MAX_DEFAULT / ratio ||
2677 		    journal->j_trans_max < JOURNAL_TRANS_MIN_DEFAULT / ratio ||
2678 		    SB_ONDISK_JOURNAL_SIZE(sb) / journal->j_trans_max <
2679 		    JOURNAL_MIN_RATIO) {
2680 			reiserfs_warning(sb, "sh-462",
2681 					 "bad transaction max size (%u). "
2682 					 "FSCK?", journal->j_trans_max);
2683 			return 1;
2684 		}
2685 		if (journal->j_max_batch != (journal->j_trans_max) *
2686 		        JOURNAL_MAX_BATCH_DEFAULT/JOURNAL_TRANS_MAX_DEFAULT) {
2687 			reiserfs_warning(sb, "sh-463",
2688 					 "bad transaction max batch (%u). "
2689 					 "FSCK?", journal->j_max_batch);
2690 			return 1;
2691 		}
2692 	} else {
2693 		/*
2694 		 * Default journal params.
2695 		 * The file system was created by old version
2696 		 * of mkreiserfs, so some fields contain zeros,
2697 		 * and we need to advise proper values for them
2698 		 */
2699 		if (sb->s_blocksize != REISERFS_STANDARD_BLKSIZE) {
2700 			reiserfs_warning(sb, "sh-464", "bad blocksize (%u)",
2701 					 sb->s_blocksize);
2702 			return 1;
2703 		}
2704 		journal->j_trans_max = JOURNAL_TRANS_MAX_DEFAULT;
2705 		journal->j_max_batch = JOURNAL_MAX_BATCH_DEFAULT;
2706 		journal->j_max_commit_age = JOURNAL_MAX_COMMIT_AGE;
2707 	}
2708 	return 0;
2709 }
2710 
2711 /* must be called once on fs mount.  calls journal_read for you */
2712 int journal_init(struct super_block *sb, const char *j_dev_name,
2713 		 int old_format, unsigned int commit_max_age)
2714 {
2715 	int num_cnodes = SB_ONDISK_JOURNAL_SIZE(sb) * 2;
2716 	struct buffer_head *bhjh;
2717 	struct reiserfs_super_block *rs;
2718 	struct reiserfs_journal_header *jh;
2719 	struct reiserfs_journal *journal;
2720 	struct reiserfs_journal_list *jl;
2721 	int ret;
2722 
2723 	journal = SB_JOURNAL(sb) = vzalloc(sizeof(struct reiserfs_journal));
2724 	if (!journal) {
2725 		reiserfs_warning(sb, "journal-1256",
2726 				 "unable to get memory for journal structure");
2727 		return 1;
2728 	}
2729 	INIT_LIST_HEAD(&journal->j_bitmap_nodes);
2730 	INIT_LIST_HEAD(&journal->j_prealloc_list);
2731 	INIT_LIST_HEAD(&journal->j_working_list);
2732 	INIT_LIST_HEAD(&journal->j_journal_list);
2733 	journal->j_persistent_trans = 0;
2734 	if (reiserfs_allocate_list_bitmaps(sb, journal->j_list_bitmap,
2735 					   reiserfs_bmap_count(sb)))
2736 		goto free_and_return;
2737 
2738 	allocate_bitmap_nodes(sb);
2739 
2740 	/* reserved for journal area support */
2741 	SB_JOURNAL_1st_RESERVED_BLOCK(sb) = (old_format ?
2742 						 REISERFS_OLD_DISK_OFFSET_IN_BYTES
2743 						 / sb->s_blocksize +
2744 						 reiserfs_bmap_count(sb) +
2745 						 1 :
2746 						 REISERFS_DISK_OFFSET_IN_BYTES /
2747 						 sb->s_blocksize + 2);
2748 
2749 	/*
2750 	 * Sanity check to see is the standard journal fitting
2751 	 * within first bitmap (actual for small blocksizes)
2752 	 */
2753 	if (!SB_ONDISK_JOURNAL_DEVICE(sb) &&
2754 	    (SB_JOURNAL_1st_RESERVED_BLOCK(sb) +
2755 	     SB_ONDISK_JOURNAL_SIZE(sb) > sb->s_blocksize * 8)) {
2756 		reiserfs_warning(sb, "journal-1393",
2757 				 "journal does not fit for area addressed "
2758 				 "by first of bitmap blocks. It starts at "
2759 				 "%u and its size is %u. Block size %ld",
2760 				 SB_JOURNAL_1st_RESERVED_BLOCK(sb),
2761 				 SB_ONDISK_JOURNAL_SIZE(sb),
2762 				 sb->s_blocksize);
2763 		goto free_and_return;
2764 	}
2765 
2766 	/*
2767 	 * Sanity check to see if journal first block is correct.
2768 	 * If journal first block is invalid it can cause
2769 	 * zeroing important superblock members.
2770 	 */
2771 	if (!SB_ONDISK_JOURNAL_DEVICE(sb) &&
2772 	    SB_ONDISK_JOURNAL_1st_BLOCK(sb) < SB_JOURNAL_1st_RESERVED_BLOCK(sb)) {
2773 		reiserfs_warning(sb, "journal-1393",
2774 				 "journal 1st super block is invalid: 1st reserved block %d, but actual 1st block is %d",
2775 				 SB_JOURNAL_1st_RESERVED_BLOCK(sb),
2776 				 SB_ONDISK_JOURNAL_1st_BLOCK(sb));
2777 		goto free_and_return;
2778 	}
2779 
2780 	if (journal_init_dev(sb, journal, j_dev_name) != 0) {
2781 		reiserfs_warning(sb, "sh-462",
2782 				 "unable to initialize journal device");
2783 		goto free_and_return;
2784 	}
2785 
2786 	rs = SB_DISK_SUPER_BLOCK(sb);
2787 
2788 	/* read journal header */
2789 	bhjh = journal_bread(sb,
2790 			     SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2791 			     SB_ONDISK_JOURNAL_SIZE(sb));
2792 	if (!bhjh) {
2793 		reiserfs_warning(sb, "sh-459",
2794 				 "unable to read journal header");
2795 		goto free_and_return;
2796 	}
2797 	jh = (struct reiserfs_journal_header *)(bhjh->b_data);
2798 
2799 	/* make sure that journal matches to the super block */
2800 	if (is_reiserfs_jr(rs)
2801 	    && (le32_to_cpu(jh->jh_journal.jp_journal_magic) !=
2802 		sb_jp_journal_magic(rs))) {
2803 		reiserfs_warning(sb, "sh-460",
2804 				 "journal header magic %x (device %pg) does "
2805 				 "not match to magic found in super block %x",
2806 				 jh->jh_journal.jp_journal_magic,
2807 				 file_bdev(journal->j_bdev_file),
2808 				 sb_jp_journal_magic(rs));
2809 		brelse(bhjh);
2810 		goto free_and_return;
2811 	}
2812 
2813 	journal->j_trans_max = le32_to_cpu(jh->jh_journal.jp_journal_trans_max);
2814 	journal->j_max_batch = le32_to_cpu(jh->jh_journal.jp_journal_max_batch);
2815 	journal->j_max_commit_age =
2816 	    le32_to_cpu(jh->jh_journal.jp_journal_max_commit_age);
2817 	journal->j_max_trans_age = JOURNAL_MAX_TRANS_AGE;
2818 
2819 	if (check_advise_trans_params(sb, journal) != 0)
2820 	        goto free_and_return;
2821 	journal->j_default_max_commit_age = journal->j_max_commit_age;
2822 
2823 	if (commit_max_age != 0) {
2824 		journal->j_max_commit_age = commit_max_age;
2825 		journal->j_max_trans_age = commit_max_age;
2826 	}
2827 
2828 	reiserfs_info(sb, "journal params: device %pg, size %u, "
2829 		      "journal first block %u, max trans len %u, max batch %u, "
2830 		      "max commit age %u, max trans age %u\n",
2831 		      file_bdev(journal->j_bdev_file),
2832 		      SB_ONDISK_JOURNAL_SIZE(sb),
2833 		      SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2834 		      journal->j_trans_max,
2835 		      journal->j_max_batch,
2836 		      journal->j_max_commit_age, journal->j_max_trans_age);
2837 
2838 	brelse(bhjh);
2839 
2840 	journal->j_list_bitmap_index = 0;
2841 	journal_list_init(sb);
2842 
2843 	memset(journal->j_list_hash_table, 0,
2844 	       JOURNAL_HASH_SIZE * sizeof(struct reiserfs_journal_cnode *));
2845 
2846 	INIT_LIST_HEAD(&journal->j_dirty_buffers);
2847 	spin_lock_init(&journal->j_dirty_buffers_lock);
2848 
2849 	journal->j_start = 0;
2850 	journal->j_len = 0;
2851 	journal->j_len_alloc = 0;
2852 	atomic_set(&journal->j_wcount, 0);
2853 	atomic_set(&journal->j_async_throttle, 0);
2854 	journal->j_bcount = 0;
2855 	journal->j_trans_start_time = 0;
2856 	journal->j_last = NULL;
2857 	journal->j_first = NULL;
2858 	init_waitqueue_head(&journal->j_join_wait);
2859 	mutex_init(&journal->j_mutex);
2860 	mutex_init(&journal->j_flush_mutex);
2861 
2862 	journal->j_trans_id = 10;
2863 	journal->j_mount_id = 10;
2864 	journal->j_state = 0;
2865 	atomic_set(&journal->j_jlock, 0);
2866 	journal->j_cnode_free_list = allocate_cnodes(num_cnodes);
2867 	journal->j_cnode_free_orig = journal->j_cnode_free_list;
2868 	journal->j_cnode_free = journal->j_cnode_free_list ? num_cnodes : 0;
2869 	journal->j_cnode_used = 0;
2870 	journal->j_must_wait = 0;
2871 
2872 	if (journal->j_cnode_free == 0) {
2873 		reiserfs_warning(sb, "journal-2004", "Journal cnode memory "
2874 		                 "allocation failed (%ld bytes). Journal is "
2875 		                 "too large for available memory. Usually "
2876 		                 "this is due to a journal that is too large.",
2877 		                 sizeof (struct reiserfs_journal_cnode) * num_cnodes);
2878         	goto free_and_return;
2879 	}
2880 
2881 	init_journal_hash(sb);
2882 	jl = journal->j_current_jl;
2883 
2884 	/*
2885 	 * get_list_bitmap() may call flush_commit_list() which
2886 	 * requires the lock. Calling flush_commit_list() shouldn't happen
2887 	 * this early but I like to be paranoid.
2888 	 */
2889 	reiserfs_write_lock(sb);
2890 	jl->j_list_bitmap = get_list_bitmap(sb, jl);
2891 	reiserfs_write_unlock(sb);
2892 	if (!jl->j_list_bitmap) {
2893 		reiserfs_warning(sb, "journal-2005",
2894 				 "get_list_bitmap failed for journal list 0");
2895 		goto free_and_return;
2896 	}
2897 
2898 	ret = journal_read(sb);
2899 	if (ret < 0) {
2900 		reiserfs_warning(sb, "reiserfs-2006",
2901 				 "Replay Failure, unable to mount");
2902 		goto free_and_return;
2903 	}
2904 
2905 	INIT_DELAYED_WORK(&journal->j_work, flush_async_commits);
2906 	journal->j_work_sb = sb;
2907 	return 0;
2908 free_and_return:
2909 	free_journal_ram(sb);
2910 	return 1;
2911 }
2912 
2913 /*
2914  * test for a polite end of the current transaction.  Used by file_write,
2915  * and should be used by delete to make sure they don't write more than
2916  * can fit inside a single transaction
2917  */
2918 int journal_transaction_should_end(struct reiserfs_transaction_handle *th,
2919 				   int new_alloc)
2920 {
2921 	struct reiserfs_journal *journal = SB_JOURNAL(th->t_super);
2922 	time64_t now = ktime_get_seconds();
2923 	/* cannot restart while nested */
2924 	BUG_ON(!th->t_trans_id);
2925 	if (th->t_refcount > 1)
2926 		return 0;
2927 	if (journal->j_must_wait > 0 ||
2928 	    (journal->j_len_alloc + new_alloc) >= journal->j_max_batch ||
2929 	    atomic_read(&journal->j_jlock) ||
2930 	    (now - journal->j_trans_start_time) > journal->j_max_trans_age ||
2931 	    journal->j_cnode_free < (journal->j_trans_max * 3)) {
2932 		return 1;
2933 	}
2934 
2935 	journal->j_len_alloc += new_alloc;
2936 	th->t_blocks_allocated += new_alloc ;
2937 	return 0;
2938 }
2939 
2940 /* this must be called inside a transaction */
2941 void reiserfs_block_writes(struct reiserfs_transaction_handle *th)
2942 {
2943 	struct reiserfs_journal *journal = SB_JOURNAL(th->t_super);
2944 	BUG_ON(!th->t_trans_id);
2945 	journal->j_must_wait = 1;
2946 	set_bit(J_WRITERS_BLOCKED, &journal->j_state);
2947 	return;
2948 }
2949 
2950 /* this must be called without a transaction started */
2951 void reiserfs_allow_writes(struct super_block *s)
2952 {
2953 	struct reiserfs_journal *journal = SB_JOURNAL(s);
2954 	clear_bit(J_WRITERS_BLOCKED, &journal->j_state);
2955 	wake_up(&journal->j_join_wait);
2956 }
2957 
2958 /* this must be called without a transaction started */
2959 void reiserfs_wait_on_write_block(struct super_block *s)
2960 {
2961 	struct reiserfs_journal *journal = SB_JOURNAL(s);
2962 	wait_event(journal->j_join_wait,
2963 		   !test_bit(J_WRITERS_BLOCKED, &journal->j_state));
2964 }
2965 
2966 static void queue_log_writer(struct super_block *s)
2967 {
2968 	wait_queue_entry_t wait;
2969 	struct reiserfs_journal *journal = SB_JOURNAL(s);
2970 	set_bit(J_WRITERS_QUEUED, &journal->j_state);
2971 
2972 	/*
2973 	 * we don't want to use wait_event here because
2974 	 * we only want to wait once.
2975 	 */
2976 	init_waitqueue_entry(&wait, current);
2977 	add_wait_queue(&journal->j_join_wait, &wait);
2978 	set_current_state(TASK_UNINTERRUPTIBLE);
2979 	if (test_bit(J_WRITERS_QUEUED, &journal->j_state)) {
2980 		int depth = reiserfs_write_unlock_nested(s);
2981 		schedule();
2982 		reiserfs_write_lock_nested(s, depth);
2983 	}
2984 	__set_current_state(TASK_RUNNING);
2985 	remove_wait_queue(&journal->j_join_wait, &wait);
2986 }
2987 
2988 static void wake_queued_writers(struct super_block *s)
2989 {
2990 	struct reiserfs_journal *journal = SB_JOURNAL(s);
2991 	if (test_and_clear_bit(J_WRITERS_QUEUED, &journal->j_state))
2992 		wake_up(&journal->j_join_wait);
2993 }
2994 
2995 static void let_transaction_grow(struct super_block *sb, unsigned int trans_id)
2996 {
2997 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
2998 	unsigned long bcount = journal->j_bcount;
2999 	while (1) {
3000 		int depth;
3001 
3002 		depth = reiserfs_write_unlock_nested(sb);
3003 		schedule_timeout_uninterruptible(1);
3004 		reiserfs_write_lock_nested(sb, depth);
3005 
3006 		journal->j_current_jl->j_state |= LIST_COMMIT_PENDING;
3007 		while ((atomic_read(&journal->j_wcount) > 0 ||
3008 			atomic_read(&journal->j_jlock)) &&
3009 		       journal->j_trans_id == trans_id) {
3010 			queue_log_writer(sb);
3011 		}
3012 		if (journal->j_trans_id != trans_id)
3013 			break;
3014 		if (bcount == journal->j_bcount)
3015 			break;
3016 		bcount = journal->j_bcount;
3017 	}
3018 }
3019 
3020 /*
3021  * join == true if you must join an existing transaction.
3022  * join == false if you can deal with waiting for others to finish
3023  *
3024  * this will block until the transaction is joinable.  send the number of
3025  * blocks you expect to use in nblocks.
3026 */
3027 static int do_journal_begin_r(struct reiserfs_transaction_handle *th,
3028 			      struct super_block *sb, unsigned long nblocks,
3029 			      int join)
3030 {
3031 	time64_t now = ktime_get_seconds();
3032 	unsigned int old_trans_id;
3033 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3034 	struct reiserfs_transaction_handle myth;
3035 	int retval;
3036 	int depth;
3037 
3038 	reiserfs_check_lock_depth(sb, "journal_begin");
3039 	BUG_ON(nblocks > journal->j_trans_max);
3040 
3041 	PROC_INFO_INC(sb, journal.journal_being);
3042 	/* set here for journal_join */
3043 	th->t_refcount = 1;
3044 	th->t_super = sb;
3045 
3046 relock:
3047 	lock_journal(sb);
3048 	if (join != JBEGIN_ABORT && reiserfs_is_journal_aborted(journal)) {
3049 		unlock_journal(sb);
3050 		retval = journal->j_errno;
3051 		goto out_fail;
3052 	}
3053 	journal->j_bcount++;
3054 
3055 	if (test_bit(J_WRITERS_BLOCKED, &journal->j_state)) {
3056 		unlock_journal(sb);
3057 		depth = reiserfs_write_unlock_nested(sb);
3058 		reiserfs_wait_on_write_block(sb);
3059 		reiserfs_write_lock_nested(sb, depth);
3060 		PROC_INFO_INC(sb, journal.journal_relock_writers);
3061 		goto relock;
3062 	}
3063 	now = ktime_get_seconds();
3064 
3065 	/*
3066 	 * if there is no room in the journal OR
3067 	 * if this transaction is too old, and we weren't called joinable,
3068 	 * wait for it to finish before beginning we don't sleep if there
3069 	 * aren't other writers
3070 	 */
3071 
3072 	if ((!join && journal->j_must_wait > 0) ||
3073 	    (!join
3074 	     && (journal->j_len_alloc + nblocks + 2) >= journal->j_max_batch)
3075 	    || (!join && atomic_read(&journal->j_wcount) > 0
3076 		&& journal->j_trans_start_time > 0
3077 		&& (now - journal->j_trans_start_time) >
3078 		journal->j_max_trans_age) || (!join
3079 					      && atomic_read(&journal->j_jlock))
3080 	    || (!join && journal->j_cnode_free < (journal->j_trans_max * 3))) {
3081 
3082 		old_trans_id = journal->j_trans_id;
3083 		/* allow others to finish this transaction */
3084 		unlock_journal(sb);
3085 
3086 		if (!join && (journal->j_len_alloc + nblocks + 2) >=
3087 		    journal->j_max_batch &&
3088 		    ((journal->j_len + nblocks + 2) * 100) <
3089 		    (journal->j_len_alloc * 75)) {
3090 			if (atomic_read(&journal->j_wcount) > 10) {
3091 				queue_log_writer(sb);
3092 				goto relock;
3093 			}
3094 		}
3095 		/*
3096 		 * don't mess with joining the transaction if all we
3097 		 * have to do is wait for someone else to do a commit
3098 		 */
3099 		if (atomic_read(&journal->j_jlock)) {
3100 			while (journal->j_trans_id == old_trans_id &&
3101 			       atomic_read(&journal->j_jlock)) {
3102 				queue_log_writer(sb);
3103 			}
3104 			goto relock;
3105 		}
3106 		retval = journal_join(&myth, sb);
3107 		if (retval)
3108 			goto out_fail;
3109 
3110 		/* someone might have ended the transaction while we joined */
3111 		if (old_trans_id != journal->j_trans_id) {
3112 			retval = do_journal_end(&myth, 0);
3113 		} else {
3114 			retval = do_journal_end(&myth, COMMIT_NOW);
3115 		}
3116 
3117 		if (retval)
3118 			goto out_fail;
3119 
3120 		PROC_INFO_INC(sb, journal.journal_relock_wcount);
3121 		goto relock;
3122 	}
3123 	/* we are the first writer, set trans_id */
3124 	if (journal->j_trans_start_time == 0) {
3125 		journal->j_trans_start_time = ktime_get_seconds();
3126 	}
3127 	atomic_inc(&journal->j_wcount);
3128 	journal->j_len_alloc += nblocks;
3129 	th->t_blocks_logged = 0;
3130 	th->t_blocks_allocated = nblocks;
3131 	th->t_trans_id = journal->j_trans_id;
3132 	unlock_journal(sb);
3133 	INIT_LIST_HEAD(&th->t_list);
3134 	return 0;
3135 
3136 out_fail:
3137 	memset(th, 0, sizeof(*th));
3138 	/*
3139 	 * Re-set th->t_super, so we can properly keep track of how many
3140 	 * persistent transactions there are. We need to do this so if this
3141 	 * call is part of a failed restart_transaction, we can free it later
3142 	 */
3143 	th->t_super = sb;
3144 	return retval;
3145 }
3146 
3147 struct reiserfs_transaction_handle *reiserfs_persistent_transaction(struct
3148 								    super_block
3149 								    *s,
3150 								    int nblocks)
3151 {
3152 	int ret;
3153 	struct reiserfs_transaction_handle *th;
3154 
3155 	/*
3156 	 * if we're nesting into an existing transaction.  It will be
3157 	 * persistent on its own
3158 	 */
3159 	if (reiserfs_transaction_running(s)) {
3160 		th = current->journal_info;
3161 		th->t_refcount++;
3162 		BUG_ON(th->t_refcount < 2);
3163 
3164 		return th;
3165 	}
3166 	th = kmalloc(sizeof(struct reiserfs_transaction_handle), GFP_NOFS);
3167 	if (!th)
3168 		return NULL;
3169 	ret = journal_begin(th, s, nblocks);
3170 	if (ret) {
3171 		kfree(th);
3172 		return NULL;
3173 	}
3174 
3175 	SB_JOURNAL(s)->j_persistent_trans++;
3176 	return th;
3177 }
3178 
3179 int reiserfs_end_persistent_transaction(struct reiserfs_transaction_handle *th)
3180 {
3181 	struct super_block *s = th->t_super;
3182 	int ret = 0;
3183 	if (th->t_trans_id)
3184 		ret = journal_end(th);
3185 	else
3186 		ret = -EIO;
3187 	if (th->t_refcount == 0) {
3188 		SB_JOURNAL(s)->j_persistent_trans--;
3189 		kfree(th);
3190 	}
3191 	return ret;
3192 }
3193 
3194 static int journal_join(struct reiserfs_transaction_handle *th,
3195 			struct super_block *sb)
3196 {
3197 	struct reiserfs_transaction_handle *cur_th = current->journal_info;
3198 
3199 	/*
3200 	 * this keeps do_journal_end from NULLing out the
3201 	 * current->journal_info pointer
3202 	 */
3203 	th->t_handle_save = cur_th;
3204 	BUG_ON(cur_th && cur_th->t_refcount > 1);
3205 	return do_journal_begin_r(th, sb, 1, JBEGIN_JOIN);
3206 }
3207 
3208 int journal_join_abort(struct reiserfs_transaction_handle *th,
3209 		       struct super_block *sb)
3210 {
3211 	struct reiserfs_transaction_handle *cur_th = current->journal_info;
3212 
3213 	/*
3214 	 * this keeps do_journal_end from NULLing out the
3215 	 * current->journal_info pointer
3216 	 */
3217 	th->t_handle_save = cur_th;
3218 	BUG_ON(cur_th && cur_th->t_refcount > 1);
3219 	return do_journal_begin_r(th, sb, 1, JBEGIN_ABORT);
3220 }
3221 
3222 int journal_begin(struct reiserfs_transaction_handle *th,
3223 		  struct super_block *sb, unsigned long nblocks)
3224 {
3225 	struct reiserfs_transaction_handle *cur_th = current->journal_info;
3226 	int ret;
3227 
3228 	th->t_handle_save = NULL;
3229 	if (cur_th) {
3230 		/* we are nesting into the current transaction */
3231 		if (cur_th->t_super == sb) {
3232 			BUG_ON(!cur_th->t_refcount);
3233 			cur_th->t_refcount++;
3234 			memcpy(th, cur_th, sizeof(*th));
3235 			if (th->t_refcount <= 1)
3236 				reiserfs_warning(sb, "reiserfs-2005",
3237 						 "BAD: refcount <= 1, but "
3238 						 "journal_info != 0");
3239 			return 0;
3240 		} else {
3241 			/*
3242 			 * we've ended up with a handle from a different
3243 			 * filesystem.  save it and restore on journal_end.
3244 			 * This should never really happen...
3245 			 */
3246 			reiserfs_warning(sb, "clm-2100",
3247 					 "nesting info a different FS");
3248 			th->t_handle_save = current->journal_info;
3249 			current->journal_info = th;
3250 		}
3251 	} else {
3252 		current->journal_info = th;
3253 	}
3254 	ret = do_journal_begin_r(th, sb, nblocks, JBEGIN_REG);
3255 	BUG_ON(current->journal_info != th);
3256 
3257 	/*
3258 	 * I guess this boils down to being the reciprocal of clm-2100 above.
3259 	 * If do_journal_begin_r fails, we need to put it back, since
3260 	 * journal_end won't be called to do it. */
3261 	if (ret)
3262 		current->journal_info = th->t_handle_save;
3263 	else
3264 		BUG_ON(!th->t_refcount);
3265 
3266 	return ret;
3267 }
3268 
3269 /*
3270  * puts bh into the current transaction.  If it was already there, reorders
3271  * removes the old pointers from the hash, and puts new ones in (to make
3272  * sure replay happen in the right order).
3273  *
3274  * if it was dirty, cleans and files onto the clean list.  I can't let it
3275  * be dirty again until the transaction is committed.
3276  *
3277  * if j_len, is bigger than j_len_alloc, it pushes j_len_alloc to 10 + j_len.
3278  */
3279 int journal_mark_dirty(struct reiserfs_transaction_handle *th,
3280 		       struct buffer_head *bh)
3281 {
3282 	struct super_block *sb = th->t_super;
3283 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3284 	struct reiserfs_journal_cnode *cn = NULL;
3285 	int count_already_incd = 0;
3286 	int prepared = 0;
3287 	BUG_ON(!th->t_trans_id);
3288 
3289 	PROC_INFO_INC(sb, journal.mark_dirty);
3290 	if (th->t_trans_id != journal->j_trans_id) {
3291 		reiserfs_panic(th->t_super, "journal-1577",
3292 			       "handle trans id %ld != current trans id %ld",
3293 			       th->t_trans_id, journal->j_trans_id);
3294 	}
3295 
3296 	prepared = test_clear_buffer_journal_prepared(bh);
3297 	clear_buffer_journal_restore_dirty(bh);
3298 	/* already in this transaction, we are done */
3299 	if (buffer_journaled(bh)) {
3300 		PROC_INFO_INC(sb, journal.mark_dirty_already);
3301 		return 0;
3302 	}
3303 
3304 	/*
3305 	 * this must be turned into a panic instead of a warning.  We can't
3306 	 * allow a dirty or journal_dirty or locked buffer to be logged, as
3307 	 * some changes could get to disk too early.  NOT GOOD.
3308 	 */
3309 	if (!prepared || buffer_dirty(bh)) {
3310 		reiserfs_warning(sb, "journal-1777",
3311 				 "buffer %llu bad state "
3312 				 "%cPREPARED %cLOCKED %cDIRTY %cJDIRTY_WAIT",
3313 				 (unsigned long long)bh->b_blocknr,
3314 				 prepared ? ' ' : '!',
3315 				 buffer_locked(bh) ? ' ' : '!',
3316 				 buffer_dirty(bh) ? ' ' : '!',
3317 				 buffer_journal_dirty(bh) ? ' ' : '!');
3318 	}
3319 
3320 	if (atomic_read(&journal->j_wcount) <= 0) {
3321 		reiserfs_warning(sb, "journal-1409",
3322 				 "returning because j_wcount was %d",
3323 				 atomic_read(&journal->j_wcount));
3324 		return 1;
3325 	}
3326 	/*
3327 	 * this error means I've screwed up, and we've overflowed
3328 	 * the transaction.  Nothing can be done here, except make the
3329 	 * FS readonly or panic.
3330 	 */
3331 	if (journal->j_len >= journal->j_trans_max) {
3332 		reiserfs_panic(th->t_super, "journal-1413",
3333 			       "j_len (%lu) is too big",
3334 			       journal->j_len);
3335 	}
3336 
3337 	if (buffer_journal_dirty(bh)) {
3338 		count_already_incd = 1;
3339 		PROC_INFO_INC(sb, journal.mark_dirty_notjournal);
3340 		clear_buffer_journal_dirty(bh);
3341 	}
3342 
3343 	if (journal->j_len > journal->j_len_alloc) {
3344 		journal->j_len_alloc = journal->j_len + JOURNAL_PER_BALANCE_CNT;
3345 	}
3346 
3347 	set_buffer_journaled(bh);
3348 
3349 	/* now put this guy on the end */
3350 	if (!cn) {
3351 		cn = get_cnode(sb);
3352 		if (!cn) {
3353 			reiserfs_panic(sb, "journal-4", "get_cnode failed!");
3354 		}
3355 
3356 		if (th->t_blocks_logged == th->t_blocks_allocated) {
3357 			th->t_blocks_allocated += JOURNAL_PER_BALANCE_CNT;
3358 			journal->j_len_alloc += JOURNAL_PER_BALANCE_CNT;
3359 		}
3360 		th->t_blocks_logged++;
3361 		journal->j_len++;
3362 
3363 		cn->bh = bh;
3364 		cn->blocknr = bh->b_blocknr;
3365 		cn->sb = sb;
3366 		cn->jlist = NULL;
3367 		insert_journal_hash(journal->j_hash_table, cn);
3368 		if (!count_already_incd) {
3369 			get_bh(bh);
3370 		}
3371 	}
3372 	cn->next = NULL;
3373 	cn->prev = journal->j_last;
3374 	cn->bh = bh;
3375 	if (journal->j_last) {
3376 		journal->j_last->next = cn;
3377 		journal->j_last = cn;
3378 	} else {
3379 		journal->j_first = cn;
3380 		journal->j_last = cn;
3381 	}
3382 	reiserfs_schedule_old_flush(sb);
3383 	return 0;
3384 }
3385 
3386 int journal_end(struct reiserfs_transaction_handle *th)
3387 {
3388 	struct super_block *sb = th->t_super;
3389 	if (!current->journal_info && th->t_refcount > 1)
3390 		reiserfs_warning(sb, "REISER-NESTING",
3391 				 "th NULL, refcount %d", th->t_refcount);
3392 
3393 	if (!th->t_trans_id) {
3394 		WARN_ON(1);
3395 		return -EIO;
3396 	}
3397 
3398 	th->t_refcount--;
3399 	if (th->t_refcount > 0) {
3400 		struct reiserfs_transaction_handle *cur_th =
3401 		    current->journal_info;
3402 
3403 		/*
3404 		 * we aren't allowed to close a nested transaction on a
3405 		 * different filesystem from the one in the task struct
3406 		 */
3407 		BUG_ON(cur_th->t_super != th->t_super);
3408 
3409 		if (th != cur_th) {
3410 			memcpy(current->journal_info, th, sizeof(*th));
3411 			th->t_trans_id = 0;
3412 		}
3413 		return 0;
3414 	} else {
3415 		return do_journal_end(th, 0);
3416 	}
3417 }
3418 
3419 /*
3420  * removes from the current transaction, relsing and descrementing any counters.
3421  * also files the removed buffer directly onto the clean list
3422  *
3423  * called by journal_mark_freed when a block has been deleted
3424  *
3425  * returns 1 if it cleaned and relsed the buffer. 0 otherwise
3426  */
3427 static int remove_from_transaction(struct super_block *sb,
3428 				   b_blocknr_t blocknr, int already_cleaned)
3429 {
3430 	struct buffer_head *bh;
3431 	struct reiserfs_journal_cnode *cn;
3432 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3433 	int ret = 0;
3434 
3435 	cn = get_journal_hash_dev(sb, journal->j_hash_table, blocknr);
3436 	if (!cn || !cn->bh) {
3437 		return ret;
3438 	}
3439 	bh = cn->bh;
3440 	if (cn->prev) {
3441 		cn->prev->next = cn->next;
3442 	}
3443 	if (cn->next) {
3444 		cn->next->prev = cn->prev;
3445 	}
3446 	if (cn == journal->j_first) {
3447 		journal->j_first = cn->next;
3448 	}
3449 	if (cn == journal->j_last) {
3450 		journal->j_last = cn->prev;
3451 	}
3452 	remove_journal_hash(sb, journal->j_hash_table, NULL,
3453 			    bh->b_blocknr, 0);
3454 	clear_buffer_journaled(bh);	/* don't log this one */
3455 
3456 	if (!already_cleaned) {
3457 		clear_buffer_journal_dirty(bh);
3458 		clear_buffer_dirty(bh);
3459 		clear_buffer_journal_test(bh);
3460 		put_bh(bh);
3461 		if (atomic_read(&bh->b_count) < 0) {
3462 			reiserfs_warning(sb, "journal-1752",
3463 					 "b_count < 0");
3464 		}
3465 		ret = 1;
3466 	}
3467 	journal->j_len--;
3468 	journal->j_len_alloc--;
3469 	free_cnode(sb, cn);
3470 	return ret;
3471 }
3472 
3473 /*
3474  * for any cnode in a journal list, it can only be dirtied of all the
3475  * transactions that include it are committed to disk.
3476  * this checks through each transaction, and returns 1 if you are allowed
3477  * to dirty, and 0 if you aren't
3478  *
3479  * it is called by dirty_journal_list, which is called after
3480  * flush_commit_list has gotten all the log blocks for a given
3481  * transaction on disk
3482  *
3483  */
3484 static int can_dirty(struct reiserfs_journal_cnode *cn)
3485 {
3486 	struct super_block *sb = cn->sb;
3487 	b_blocknr_t blocknr = cn->blocknr;
3488 	struct reiserfs_journal_cnode *cur = cn->hprev;
3489 	int can_dirty = 1;
3490 
3491 	/*
3492 	 * first test hprev.  These are all newer than cn, so any node here
3493 	 * with the same block number and dev means this node can't be sent
3494 	 * to disk right now.
3495 	 */
3496 	while (cur && can_dirty) {
3497 		if (cur->jlist && cur->bh && cur->blocknr && cur->sb == sb &&
3498 		    cur->blocknr == blocknr) {
3499 			can_dirty = 0;
3500 		}
3501 		cur = cur->hprev;
3502 	}
3503 	/*
3504 	 * then test hnext.  These are all older than cn.  As long as they
3505 	 * are committed to the log, it is safe to write cn to disk
3506 	 */
3507 	cur = cn->hnext;
3508 	while (cur && can_dirty) {
3509 		if (cur->jlist && cur->jlist->j_len > 0 &&
3510 		    atomic_read(&cur->jlist->j_commit_left) > 0 && cur->bh &&
3511 		    cur->blocknr && cur->sb == sb && cur->blocknr == blocknr) {
3512 			can_dirty = 0;
3513 		}
3514 		cur = cur->hnext;
3515 	}
3516 	return can_dirty;
3517 }
3518 
3519 /*
3520  * syncs the commit blocks, but does not force the real buffers to disk
3521  * will wait until the current transaction is done/committed before returning
3522  */
3523 int journal_end_sync(struct reiserfs_transaction_handle *th)
3524 {
3525 	struct super_block *sb = th->t_super;
3526 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3527 
3528 	BUG_ON(!th->t_trans_id);
3529 	/* you can sync while nested, very, very bad */
3530 	BUG_ON(th->t_refcount > 1);
3531 	if (journal->j_len == 0) {
3532 		reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
3533 					     1);
3534 		journal_mark_dirty(th, SB_BUFFER_WITH_SB(sb));
3535 	}
3536 	return do_journal_end(th, COMMIT_NOW | WAIT);
3537 }
3538 
3539 /* writeback the pending async commits to disk */
3540 static void flush_async_commits(struct work_struct *work)
3541 {
3542 	struct reiserfs_journal *journal =
3543 		container_of(work, struct reiserfs_journal, j_work.work);
3544 	struct super_block *sb = journal->j_work_sb;
3545 	struct reiserfs_journal_list *jl;
3546 	struct list_head *entry;
3547 
3548 	reiserfs_write_lock(sb);
3549 	if (!list_empty(&journal->j_journal_list)) {
3550 		/* last entry is the youngest, commit it and you get everything */
3551 		entry = journal->j_journal_list.prev;
3552 		jl = JOURNAL_LIST_ENTRY(entry);
3553 		flush_commit_list(sb, jl, 1);
3554 	}
3555 	reiserfs_write_unlock(sb);
3556 }
3557 
3558 /*
3559  * flushes any old transactions to disk
3560  * ends the current transaction if it is too old
3561  */
3562 void reiserfs_flush_old_commits(struct super_block *sb)
3563 {
3564 	time64_t now;
3565 	struct reiserfs_transaction_handle th;
3566 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3567 
3568 	now = ktime_get_seconds();
3569 	/*
3570 	 * safety check so we don't flush while we are replaying the log during
3571 	 * mount
3572 	 */
3573 	if (list_empty(&journal->j_journal_list))
3574 		return;
3575 
3576 	/*
3577 	 * check the current transaction.  If there are no writers, and it is
3578 	 * too old, finish it, and force the commit blocks to disk
3579 	 */
3580 	if (atomic_read(&journal->j_wcount) <= 0 &&
3581 	    journal->j_trans_start_time > 0 &&
3582 	    journal->j_len > 0 &&
3583 	    (now - journal->j_trans_start_time) > journal->j_max_trans_age) {
3584 		if (!journal_join(&th, sb)) {
3585 			reiserfs_prepare_for_journal(sb,
3586 						     SB_BUFFER_WITH_SB(sb),
3587 						     1);
3588 			journal_mark_dirty(&th, SB_BUFFER_WITH_SB(sb));
3589 
3590 			/*
3591 			 * we're only being called from kreiserfsd, it makes
3592 			 * no sense to do an async commit so that kreiserfsd
3593 			 * can do it later
3594 			 */
3595 			do_journal_end(&th, COMMIT_NOW | WAIT);
3596 		}
3597 	}
3598 }
3599 
3600 /*
3601  * returns 0 if do_journal_end should return right away, returns 1 if
3602  * do_journal_end should finish the commit
3603  *
3604  * if the current transaction is too old, but still has writers, this will
3605  * wait on j_join_wait until all the writers are done.  By the time it
3606  * wakes up, the transaction it was called has already ended, so it just
3607  * flushes the commit list and returns 0.
3608  *
3609  * Won't batch when flush or commit_now is set.  Also won't batch when
3610  * others are waiting on j_join_wait.
3611  *
3612  * Note, we can't allow the journal_end to proceed while there are still
3613  * writers in the log.
3614  */
3615 static int check_journal_end(struct reiserfs_transaction_handle *th, int flags)
3616 {
3617 
3618 	time64_t now;
3619 	int flush = flags & FLUSH_ALL;
3620 	int commit_now = flags & COMMIT_NOW;
3621 	int wait_on_commit = flags & WAIT;
3622 	struct reiserfs_journal_list *jl;
3623 	struct super_block *sb = th->t_super;
3624 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3625 
3626 	BUG_ON(!th->t_trans_id);
3627 
3628 	if (th->t_trans_id != journal->j_trans_id) {
3629 		reiserfs_panic(th->t_super, "journal-1577",
3630 			       "handle trans id %ld != current trans id %ld",
3631 			       th->t_trans_id, journal->j_trans_id);
3632 	}
3633 
3634 	journal->j_len_alloc -= (th->t_blocks_allocated - th->t_blocks_logged);
3635 	/* <= 0 is allowed.  unmounting might not call begin */
3636 	if (atomic_read(&journal->j_wcount) > 0)
3637 		atomic_dec(&journal->j_wcount);
3638 
3639 	/*
3640 	 * BUG, deal with case where j_len is 0, but people previously
3641 	 * freed blocks need to be released will be dealt with by next
3642 	 * transaction that actually writes something, but should be taken
3643 	 * care of in this trans
3644 	 */
3645 	BUG_ON(journal->j_len == 0);
3646 
3647 	/*
3648 	 * if wcount > 0, and we are called to with flush or commit_now,
3649 	 * we wait on j_join_wait.  We will wake up when the last writer has
3650 	 * finished the transaction, and started it on its way to the disk.
3651 	 * Then, we flush the commit or journal list, and just return 0
3652 	 * because the rest of journal end was already done for this
3653 	 * transaction.
3654 	 */
3655 	if (atomic_read(&journal->j_wcount) > 0) {
3656 		if (flush || commit_now) {
3657 			unsigned trans_id;
3658 
3659 			jl = journal->j_current_jl;
3660 			trans_id = jl->j_trans_id;
3661 			if (wait_on_commit)
3662 				jl->j_state |= LIST_COMMIT_PENDING;
3663 			atomic_set(&journal->j_jlock, 1);
3664 			if (flush) {
3665 				journal->j_next_full_flush = 1;
3666 			}
3667 			unlock_journal(sb);
3668 
3669 			/*
3670 			 * sleep while the current transaction is
3671 			 * still j_jlocked
3672 			 */
3673 			while (journal->j_trans_id == trans_id) {
3674 				if (atomic_read(&journal->j_jlock)) {
3675 					queue_log_writer(sb);
3676 				} else {
3677 					lock_journal(sb);
3678 					if (journal->j_trans_id == trans_id) {
3679 						atomic_set(&journal->j_jlock,
3680 							   1);
3681 					}
3682 					unlock_journal(sb);
3683 				}
3684 			}
3685 			BUG_ON(journal->j_trans_id == trans_id);
3686 
3687 			if (commit_now
3688 			    && journal_list_still_alive(sb, trans_id)
3689 			    && wait_on_commit) {
3690 				flush_commit_list(sb, jl, 1);
3691 			}
3692 			return 0;
3693 		}
3694 		unlock_journal(sb);
3695 		return 0;
3696 	}
3697 
3698 	/* deal with old transactions where we are the last writers */
3699 	now = ktime_get_seconds();
3700 	if ((now - journal->j_trans_start_time) > journal->j_max_trans_age) {
3701 		commit_now = 1;
3702 		journal->j_next_async_flush = 1;
3703 	}
3704 	/* don't batch when someone is waiting on j_join_wait */
3705 	/* don't batch when syncing the commit or flushing the whole trans */
3706 	if (!(journal->j_must_wait > 0) && !(atomic_read(&journal->j_jlock))
3707 	    && !flush && !commit_now && (journal->j_len < journal->j_max_batch)
3708 	    && journal->j_len_alloc < journal->j_max_batch
3709 	    && journal->j_cnode_free > (journal->j_trans_max * 3)) {
3710 		journal->j_bcount++;
3711 		unlock_journal(sb);
3712 		return 0;
3713 	}
3714 
3715 	if (journal->j_start > SB_ONDISK_JOURNAL_SIZE(sb)) {
3716 		reiserfs_panic(sb, "journal-003",
3717 			       "j_start (%ld) is too high",
3718 			       journal->j_start);
3719 	}
3720 	return 1;
3721 }
3722 
3723 /*
3724  * Does all the work that makes deleting blocks safe.
3725  * when deleting a block mark BH_JNew, just remove it from the current
3726  * transaction, clean it's buffer_head and move on.
3727  *
3728  * otherwise:
3729  * set a bit for the block in the journal bitmap.  That will prevent it from
3730  * being allocated for unformatted nodes before this transaction has finished.
3731  *
3732  * mark any cnodes for this block as BLOCK_FREED, and clear their bh pointers.
3733  * That will prevent any old transactions with this block from trying to flush
3734  * to the real location.  Since we aren't removing the cnode from the
3735  * journal_list_hash, *the block can't be reallocated yet.
3736  *
3737  * Then remove it from the current transaction, decrementing any counters and
3738  * filing it on the clean list.
3739  */
3740 int journal_mark_freed(struct reiserfs_transaction_handle *th,
3741 		       struct super_block *sb, b_blocknr_t blocknr)
3742 {
3743 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3744 	struct reiserfs_journal_cnode *cn = NULL;
3745 	struct buffer_head *bh = NULL;
3746 	struct reiserfs_list_bitmap *jb = NULL;
3747 	int cleaned = 0;
3748 	BUG_ON(!th->t_trans_id);
3749 
3750 	cn = get_journal_hash_dev(sb, journal->j_hash_table, blocknr);
3751 	if (cn && cn->bh) {
3752 		bh = cn->bh;
3753 		get_bh(bh);
3754 	}
3755 	/* if it is journal new, we just remove it from this transaction */
3756 	if (bh && buffer_journal_new(bh)) {
3757 		clear_buffer_journal_new(bh);
3758 		clear_prepared_bits(bh);
3759 		reiserfs_clean_and_file_buffer(bh);
3760 		cleaned = remove_from_transaction(sb, blocknr, cleaned);
3761 	} else {
3762 		/*
3763 		 * set the bit for this block in the journal bitmap
3764 		 * for this transaction
3765 		 */
3766 		jb = journal->j_current_jl->j_list_bitmap;
3767 		if (!jb) {
3768 			reiserfs_panic(sb, "journal-1702",
3769 				       "journal_list_bitmap is NULL");
3770 		}
3771 		set_bit_in_list_bitmap(sb, blocknr, jb);
3772 
3773 		/* Note, the entire while loop is not allowed to schedule.  */
3774 
3775 		if (bh) {
3776 			clear_prepared_bits(bh);
3777 			reiserfs_clean_and_file_buffer(bh);
3778 		}
3779 		cleaned = remove_from_transaction(sb, blocknr, cleaned);
3780 
3781 		/*
3782 		 * find all older transactions with this block,
3783 		 * make sure they don't try to write it out
3784 		 */
3785 		cn = get_journal_hash_dev(sb, journal->j_list_hash_table,
3786 					  blocknr);
3787 		while (cn) {
3788 			if (sb == cn->sb && blocknr == cn->blocknr) {
3789 				set_bit(BLOCK_FREED, &cn->state);
3790 				if (cn->bh) {
3791 					/*
3792 					 * remove_from_transaction will brelse
3793 					 * the buffer if it was in the current
3794 					 * trans
3795 					 */
3796 					if (!cleaned) {
3797 						clear_buffer_journal_dirty(cn->
3798 									   bh);
3799 						clear_buffer_dirty(cn->bh);
3800 						clear_buffer_journal_test(cn->
3801 									  bh);
3802 						cleaned = 1;
3803 						put_bh(cn->bh);
3804 						if (atomic_read
3805 						    (&cn->bh->b_count) < 0) {
3806 							reiserfs_warning(sb,
3807 								 "journal-2138",
3808 								 "cn->bh->b_count < 0");
3809 						}
3810 					}
3811 					/*
3812 					 * since we are clearing the bh,
3813 					 * we MUST dec nonzerolen
3814 					 */
3815 					if (cn->jlist) {
3816 						atomic_dec(&cn->jlist->
3817 							   j_nonzerolen);
3818 					}
3819 					cn->bh = NULL;
3820 				}
3821 			}
3822 			cn = cn->hnext;
3823 		}
3824 	}
3825 
3826 	if (bh)
3827 		release_buffer_page(bh); /* get_hash grabs the buffer */
3828 	return 0;
3829 }
3830 
3831 void reiserfs_update_inode_transaction(struct inode *inode)
3832 {
3833 	struct reiserfs_journal *journal = SB_JOURNAL(inode->i_sb);
3834 	REISERFS_I(inode)->i_jl = journal->j_current_jl;
3835 	REISERFS_I(inode)->i_trans_id = journal->j_trans_id;
3836 }
3837 
3838 /*
3839  * returns -1 on error, 0 if no commits/barriers were done and 1
3840  * if a transaction was actually committed and the barrier was done
3841  */
3842 static int __commit_trans_jl(struct inode *inode, unsigned long id,
3843 			     struct reiserfs_journal_list *jl)
3844 {
3845 	struct reiserfs_transaction_handle th;
3846 	struct super_block *sb = inode->i_sb;
3847 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3848 	int ret = 0;
3849 
3850 	/*
3851 	 * is it from the current transaction,
3852 	 * or from an unknown transaction?
3853 	 */
3854 	if (id == journal->j_trans_id) {
3855 		jl = journal->j_current_jl;
3856 		/*
3857 		 * try to let other writers come in and
3858 		 * grow this transaction
3859 		 */
3860 		let_transaction_grow(sb, id);
3861 		if (journal->j_trans_id != id) {
3862 			goto flush_commit_only;
3863 		}
3864 
3865 		ret = journal_begin(&th, sb, 1);
3866 		if (ret)
3867 			return ret;
3868 
3869 		/* someone might have ended this transaction while we joined */
3870 		if (journal->j_trans_id != id) {
3871 			reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
3872 						     1);
3873 			journal_mark_dirty(&th, SB_BUFFER_WITH_SB(sb));
3874 			ret = journal_end(&th);
3875 			goto flush_commit_only;
3876 		}
3877 
3878 		ret = journal_end_sync(&th);
3879 		if (!ret)
3880 			ret = 1;
3881 
3882 	} else {
3883 		/*
3884 		 * this gets tricky, we have to make sure the journal list in
3885 		 * the inode still exists.  We know the list is still around
3886 		 * if we've got a larger transaction id than the oldest list
3887 		 */
3888 flush_commit_only:
3889 		if (journal_list_still_alive(inode->i_sb, id)) {
3890 			/*
3891 			 * we only set ret to 1 when we know for sure
3892 			 * the barrier hasn't been started yet on the commit
3893 			 * block.
3894 			 */
3895 			if (atomic_read(&jl->j_commit_left) > 1)
3896 				ret = 1;
3897 			flush_commit_list(sb, jl, 1);
3898 			if (journal->j_errno)
3899 				ret = journal->j_errno;
3900 		}
3901 	}
3902 	/* otherwise the list is gone, and long since committed */
3903 	return ret;
3904 }
3905 
3906 int reiserfs_commit_for_inode(struct inode *inode)
3907 {
3908 	unsigned int id = REISERFS_I(inode)->i_trans_id;
3909 	struct reiserfs_journal_list *jl = REISERFS_I(inode)->i_jl;
3910 
3911 	/*
3912 	 * for the whole inode, assume unset id means it was
3913 	 * changed in the current transaction.  More conservative
3914 	 */
3915 	if (!id || !jl) {
3916 		reiserfs_update_inode_transaction(inode);
3917 		id = REISERFS_I(inode)->i_trans_id;
3918 		/* jl will be updated in __commit_trans_jl */
3919 	}
3920 
3921 	return __commit_trans_jl(inode, id, jl);
3922 }
3923 
3924 void reiserfs_restore_prepared_buffer(struct super_block *sb,
3925 				      struct buffer_head *bh)
3926 {
3927 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3928 	PROC_INFO_INC(sb, journal.restore_prepared);
3929 	if (!bh) {
3930 		return;
3931 	}
3932 	if (test_clear_buffer_journal_restore_dirty(bh) &&
3933 	    buffer_journal_dirty(bh)) {
3934 		struct reiserfs_journal_cnode *cn;
3935 		reiserfs_write_lock(sb);
3936 		cn = get_journal_hash_dev(sb,
3937 					  journal->j_list_hash_table,
3938 					  bh->b_blocknr);
3939 		if (cn && can_dirty(cn)) {
3940 			set_buffer_journal_test(bh);
3941 			mark_buffer_dirty(bh);
3942 		}
3943 		reiserfs_write_unlock(sb);
3944 	}
3945 	clear_buffer_journal_prepared(bh);
3946 }
3947 
3948 extern struct tree_balance *cur_tb;
3949 /*
3950  * before we can change a metadata block, we have to make sure it won't
3951  * be written to disk while we are altering it.  So, we must:
3952  * clean it
3953  * wait on it.
3954  */
3955 int reiserfs_prepare_for_journal(struct super_block *sb,
3956 				 struct buffer_head *bh, int wait)
3957 {
3958 	PROC_INFO_INC(sb, journal.prepare);
3959 
3960 	if (!trylock_buffer(bh)) {
3961 		if (!wait)
3962 			return 0;
3963 		lock_buffer(bh);
3964 	}
3965 	set_buffer_journal_prepared(bh);
3966 	if (test_clear_buffer_dirty(bh) && buffer_journal_dirty(bh)) {
3967 		clear_buffer_journal_test(bh);
3968 		set_buffer_journal_restore_dirty(bh);
3969 	}
3970 	unlock_buffer(bh);
3971 	return 1;
3972 }
3973 
3974 /*
3975  * long and ugly.  If flush, will not return until all commit
3976  * blocks and all real buffers in the trans are on disk.
3977  * If no_async, won't return until all commit blocks are on disk.
3978  *
3979  * keep reading, there are comments as you go along
3980  *
3981  * If the journal is aborted, we just clean up. Things like flushing
3982  * journal lists, etc just won't happen.
3983  */
3984 static int do_journal_end(struct reiserfs_transaction_handle *th, int flags)
3985 {
3986 	struct super_block *sb = th->t_super;
3987 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3988 	struct reiserfs_journal_cnode *cn, *next, *jl_cn;
3989 	struct reiserfs_journal_cnode *last_cn = NULL;
3990 	struct reiserfs_journal_desc *desc;
3991 	struct reiserfs_journal_commit *commit;
3992 	struct buffer_head *c_bh;	/* commit bh */
3993 	struct buffer_head *d_bh;	/* desc bh */
3994 	int cur_write_start = 0;	/* start index of current log write */
3995 	int i;
3996 	int flush;
3997 	int wait_on_commit;
3998 	struct reiserfs_journal_list *jl, *temp_jl;
3999 	struct list_head *entry, *safe;
4000 	unsigned long jindex;
4001 	unsigned int commit_trans_id;
4002 	int trans_half;
4003 	int depth;
4004 
4005 	BUG_ON(th->t_refcount > 1);
4006 	BUG_ON(!th->t_trans_id);
4007 	BUG_ON(!th->t_super);
4008 
4009 	/*
4010 	 * protect flush_older_commits from doing mistakes if the
4011 	 * transaction ID counter gets overflowed.
4012 	 */
4013 	if (th->t_trans_id == ~0U)
4014 		flags |= FLUSH_ALL | COMMIT_NOW | WAIT;
4015 	flush = flags & FLUSH_ALL;
4016 	wait_on_commit = flags & WAIT;
4017 
4018 	current->journal_info = th->t_handle_save;
4019 	reiserfs_check_lock_depth(sb, "journal end");
4020 	if (journal->j_len == 0) {
4021 		reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
4022 					     1);
4023 		journal_mark_dirty(th, SB_BUFFER_WITH_SB(sb));
4024 	}
4025 
4026 	lock_journal(sb);
4027 	if (journal->j_next_full_flush) {
4028 		flags |= FLUSH_ALL;
4029 		flush = 1;
4030 	}
4031 	if (journal->j_next_async_flush) {
4032 		flags |= COMMIT_NOW | WAIT;
4033 		wait_on_commit = 1;
4034 	}
4035 
4036 	/*
4037 	 * check_journal_end locks the journal, and unlocks if it does
4038 	 * not return 1 it tells us if we should continue with the
4039 	 * journal_end, or just return
4040 	 */
4041 	if (!check_journal_end(th, flags)) {
4042 		reiserfs_schedule_old_flush(sb);
4043 		wake_queued_writers(sb);
4044 		reiserfs_async_progress_wait(sb);
4045 		goto out;
4046 	}
4047 
4048 	/* check_journal_end might set these, check again */
4049 	if (journal->j_next_full_flush) {
4050 		flush = 1;
4051 	}
4052 
4053 	/*
4054 	 * j must wait means we have to flush the log blocks, and the
4055 	 * real blocks for this transaction
4056 	 */
4057 	if (journal->j_must_wait > 0) {
4058 		flush = 1;
4059 	}
4060 #ifdef REISERFS_PREALLOCATE
4061 	/*
4062 	 * quota ops might need to nest, setup the journal_info pointer
4063 	 * for them and raise the refcount so that it is > 0.
4064 	 */
4065 	current->journal_info = th;
4066 	th->t_refcount++;
4067 
4068 	/* it should not involve new blocks into the transaction */
4069 	reiserfs_discard_all_prealloc(th);
4070 
4071 	th->t_refcount--;
4072 	current->journal_info = th->t_handle_save;
4073 #endif
4074 
4075 	/* setup description block */
4076 	d_bh =
4077 	    journal_getblk(sb,
4078 			   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
4079 			   journal->j_start);
4080 	set_buffer_uptodate(d_bh);
4081 	desc = (struct reiserfs_journal_desc *)(d_bh)->b_data;
4082 	memset(d_bh->b_data, 0, d_bh->b_size);
4083 	memcpy(get_journal_desc_magic(d_bh), JOURNAL_DESC_MAGIC, 8);
4084 	set_desc_trans_id(desc, journal->j_trans_id);
4085 
4086 	/*
4087 	 * setup commit block.  Don't write (keep it clean too) this one
4088 	 * until after everyone else is written
4089 	 */
4090 	c_bh = journal_getblk(sb, SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
4091 			      ((journal->j_start + journal->j_len +
4092 				1) % SB_ONDISK_JOURNAL_SIZE(sb)));
4093 	commit = (struct reiserfs_journal_commit *)c_bh->b_data;
4094 	memset(c_bh->b_data, 0, c_bh->b_size);
4095 	set_commit_trans_id(commit, journal->j_trans_id);
4096 	set_buffer_uptodate(c_bh);
4097 
4098 	/* init this journal list */
4099 	jl = journal->j_current_jl;
4100 
4101 	/*
4102 	 * we lock the commit before doing anything because
4103 	 * we want to make sure nobody tries to run flush_commit_list until
4104 	 * the new transaction is fully setup, and we've already flushed the
4105 	 * ordered bh list
4106 	 */
4107 	reiserfs_mutex_lock_safe(&jl->j_commit_mutex, sb);
4108 
4109 	/* save the transaction id in case we need to commit it later */
4110 	commit_trans_id = jl->j_trans_id;
4111 
4112 	atomic_set(&jl->j_older_commits_done, 0);
4113 	jl->j_trans_id = journal->j_trans_id;
4114 	jl->j_timestamp = journal->j_trans_start_time;
4115 	jl->j_commit_bh = c_bh;
4116 	jl->j_start = journal->j_start;
4117 	jl->j_len = journal->j_len;
4118 	atomic_set(&jl->j_nonzerolen, journal->j_len);
4119 	atomic_set(&jl->j_commit_left, journal->j_len + 2);
4120 	jl->j_realblock = NULL;
4121 
4122 	/*
4123 	 * The ENTIRE FOR LOOP MUST not cause schedule to occur.
4124 	 * for each real block, add it to the journal list hash,
4125 	 * copy into real block index array in the commit or desc block
4126 	 */
4127 	trans_half = journal_trans_half(sb->s_blocksize);
4128 	for (i = 0, cn = journal->j_first; cn; cn = cn->next, i++) {
4129 		if (buffer_journaled(cn->bh)) {
4130 			jl_cn = get_cnode(sb);
4131 			if (!jl_cn) {
4132 				reiserfs_panic(sb, "journal-1676",
4133 					       "get_cnode returned NULL");
4134 			}
4135 			if (i == 0) {
4136 				jl->j_realblock = jl_cn;
4137 			}
4138 			jl_cn->prev = last_cn;
4139 			jl_cn->next = NULL;
4140 			if (last_cn) {
4141 				last_cn->next = jl_cn;
4142 			}
4143 			last_cn = jl_cn;
4144 			/*
4145 			 * make sure the block we are trying to log
4146 			 * is not a block of journal or reserved area
4147 			 */
4148 			if (is_block_in_log_or_reserved_area
4149 			    (sb, cn->bh->b_blocknr)) {
4150 				reiserfs_panic(sb, "journal-2332",
4151 					       "Trying to log block %lu, "
4152 					       "which is a log block",
4153 					       cn->bh->b_blocknr);
4154 			}
4155 			jl_cn->blocknr = cn->bh->b_blocknr;
4156 			jl_cn->state = 0;
4157 			jl_cn->sb = sb;
4158 			jl_cn->bh = cn->bh;
4159 			jl_cn->jlist = jl;
4160 			insert_journal_hash(journal->j_list_hash_table, jl_cn);
4161 			if (i < trans_half) {
4162 				desc->j_realblock[i] =
4163 				    cpu_to_le32(cn->bh->b_blocknr);
4164 			} else {
4165 				commit->j_realblock[i - trans_half] =
4166 				    cpu_to_le32(cn->bh->b_blocknr);
4167 			}
4168 		} else {
4169 			i--;
4170 		}
4171 	}
4172 	set_desc_trans_len(desc, journal->j_len);
4173 	set_desc_mount_id(desc, journal->j_mount_id);
4174 	set_desc_trans_id(desc, journal->j_trans_id);
4175 	set_commit_trans_len(commit, journal->j_len);
4176 
4177 	/*
4178 	 * special check in case all buffers in the journal
4179 	 * were marked for not logging
4180 	 */
4181 	BUG_ON(journal->j_len == 0);
4182 
4183 	/*
4184 	 * we're about to dirty all the log blocks, mark the description block
4185 	 * dirty now too.  Don't mark the commit block dirty until all the
4186 	 * others are on disk
4187 	 */
4188 	mark_buffer_dirty(d_bh);
4189 
4190 	/*
4191 	 * first data block is j_start + 1, so add one to
4192 	 * cur_write_start wherever you use it
4193 	 */
4194 	cur_write_start = journal->j_start;
4195 	cn = journal->j_first;
4196 	jindex = 1;	/* start at one so we don't get the desc again */
4197 	while (cn) {
4198 		clear_buffer_journal_new(cn->bh);
4199 		/* copy all the real blocks into log area.  dirty log blocks */
4200 		if (buffer_journaled(cn->bh)) {
4201 			struct buffer_head *tmp_bh;
4202 			char *addr;
4203 			struct page *page;
4204 			tmp_bh =
4205 			    journal_getblk(sb,
4206 					   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
4207 					   ((cur_write_start +
4208 					     jindex) %
4209 					    SB_ONDISK_JOURNAL_SIZE(sb)));
4210 			set_buffer_uptodate(tmp_bh);
4211 			page = cn->bh->b_page;
4212 			addr = kmap(page);
4213 			memcpy(tmp_bh->b_data,
4214 			       addr + offset_in_page(cn->bh->b_data),
4215 			       cn->bh->b_size);
4216 			kunmap(page);
4217 			mark_buffer_dirty(tmp_bh);
4218 			jindex++;
4219 			set_buffer_journal_dirty(cn->bh);
4220 			clear_buffer_journaled(cn->bh);
4221 		} else {
4222 			/*
4223 			 * JDirty cleared sometime during transaction.
4224 			 * don't log this one
4225 			 */
4226 			reiserfs_warning(sb, "journal-2048",
4227 					 "BAD, buffer in journal hash, "
4228 					 "but not JDirty!");
4229 			brelse(cn->bh);
4230 		}
4231 		next = cn->next;
4232 		free_cnode(sb, cn);
4233 		cn = next;
4234 		reiserfs_cond_resched(sb);
4235 	}
4236 
4237 	/*
4238 	 * we are done with both the c_bh and d_bh, but
4239 	 * c_bh must be written after all other commit blocks,
4240 	 * so we dirty/relse c_bh in flush_commit_list, with commit_left <= 1.
4241 	 */
4242 
4243 	journal->j_current_jl = alloc_journal_list(sb);
4244 
4245 	/* now it is safe to insert this transaction on the main list */
4246 	list_add_tail(&jl->j_list, &journal->j_journal_list);
4247 	list_add_tail(&jl->j_working_list, &journal->j_working_list);
4248 	journal->j_num_work_lists++;
4249 
4250 	/* reset journal values for the next transaction */
4251 	journal->j_start =
4252 	    (journal->j_start + journal->j_len +
4253 	     2) % SB_ONDISK_JOURNAL_SIZE(sb);
4254 	atomic_set(&journal->j_wcount, 0);
4255 	journal->j_bcount = 0;
4256 	journal->j_last = NULL;
4257 	journal->j_first = NULL;
4258 	journal->j_len = 0;
4259 	journal->j_trans_start_time = 0;
4260 	/* check for trans_id overflow */
4261 	if (++journal->j_trans_id == 0)
4262 		journal->j_trans_id = 10;
4263 	journal->j_current_jl->j_trans_id = journal->j_trans_id;
4264 	journal->j_must_wait = 0;
4265 	journal->j_len_alloc = 0;
4266 	journal->j_next_full_flush = 0;
4267 	journal->j_next_async_flush = 0;
4268 	init_journal_hash(sb);
4269 
4270 	/*
4271 	 * make sure reiserfs_add_jh sees the new current_jl before we
4272 	 * write out the tails
4273 	 */
4274 	smp_mb();
4275 
4276 	/*
4277 	 * tail conversion targets have to hit the disk before we end the
4278 	 * transaction.  Otherwise a later transaction might repack the tail
4279 	 * before this transaction commits, leaving the data block unflushed
4280 	 * and clean, if we crash before the later transaction commits, the
4281 	 * data block is lost.
4282 	 */
4283 	if (!list_empty(&jl->j_tail_bh_list)) {
4284 		depth = reiserfs_write_unlock_nested(sb);
4285 		write_ordered_buffers(&journal->j_dirty_buffers_lock,
4286 				      journal, jl, &jl->j_tail_bh_list);
4287 		reiserfs_write_lock_nested(sb, depth);
4288 	}
4289 	BUG_ON(!list_empty(&jl->j_tail_bh_list));
4290 	mutex_unlock(&jl->j_commit_mutex);
4291 
4292 	/*
4293 	 * honor the flush wishes from the caller, simple commits can
4294 	 * be done outside the journal lock, they are done below
4295 	 *
4296 	 * if we don't flush the commit list right now, we put it into
4297 	 * the work queue so the people waiting on the async progress work
4298 	 * queue don't wait for this proc to flush journal lists and such.
4299 	 */
4300 	if (flush) {
4301 		flush_commit_list(sb, jl, 1);
4302 		flush_journal_list(sb, jl, 1);
4303 	} else if (!(jl->j_state & LIST_COMMIT_PENDING)) {
4304 		/*
4305 		 * Avoid queueing work when sb is being shut down. Transaction
4306 		 * will be flushed on journal shutdown.
4307 		 */
4308 		if (sb->s_flags & SB_ACTIVE)
4309 			queue_delayed_work(REISERFS_SB(sb)->commit_wq,
4310 					   &journal->j_work, HZ / 10);
4311 	}
4312 
4313 	/*
4314 	 * if the next transaction has any chance of wrapping, flush
4315 	 * transactions that might get overwritten.  If any journal lists
4316 	 * are very old flush them as well.
4317 	 */
4318 first_jl:
4319 	list_for_each_safe(entry, safe, &journal->j_journal_list) {
4320 		temp_jl = JOURNAL_LIST_ENTRY(entry);
4321 		if (journal->j_start <= temp_jl->j_start) {
4322 			if ((journal->j_start + journal->j_trans_max + 1) >=
4323 			    temp_jl->j_start) {
4324 				flush_used_journal_lists(sb, temp_jl);
4325 				goto first_jl;
4326 			} else if ((journal->j_start +
4327 				    journal->j_trans_max + 1) <
4328 				   SB_ONDISK_JOURNAL_SIZE(sb)) {
4329 				/*
4330 				 * if we don't cross into the next
4331 				 * transaction and we don't wrap, there is
4332 				 * no way we can overlap any later transactions
4333 				 * break now
4334 				 */
4335 				break;
4336 			}
4337 		} else if ((journal->j_start +
4338 			    journal->j_trans_max + 1) >
4339 			   SB_ONDISK_JOURNAL_SIZE(sb)) {
4340 			if (((journal->j_start + journal->j_trans_max + 1) %
4341 			     SB_ONDISK_JOURNAL_SIZE(sb)) >=
4342 			    temp_jl->j_start) {
4343 				flush_used_journal_lists(sb, temp_jl);
4344 				goto first_jl;
4345 			} else {
4346 				/*
4347 				* we don't overlap anything from out start
4348 				* to the end of the log, and our wrapped
4349 				* portion doesn't overlap anything at
4350 				* the start of the log.  We can break
4351 				*/
4352 				break;
4353 			}
4354 		}
4355 	}
4356 
4357 	journal->j_current_jl->j_list_bitmap =
4358 	    get_list_bitmap(sb, journal->j_current_jl);
4359 
4360 	if (!(journal->j_current_jl->j_list_bitmap)) {
4361 		reiserfs_panic(sb, "journal-1996",
4362 			       "could not get a list bitmap");
4363 	}
4364 
4365 	atomic_set(&journal->j_jlock, 0);
4366 	unlock_journal(sb);
4367 	/* wake up any body waiting to join. */
4368 	clear_bit(J_WRITERS_QUEUED, &journal->j_state);
4369 	wake_up(&journal->j_join_wait);
4370 
4371 	if (!flush && wait_on_commit &&
4372 	    journal_list_still_alive(sb, commit_trans_id)) {
4373 		flush_commit_list(sb, jl, 1);
4374 	}
4375 out:
4376 	reiserfs_check_lock_depth(sb, "journal end2");
4377 
4378 	memset(th, 0, sizeof(*th));
4379 	/*
4380 	 * Re-set th->t_super, so we can properly keep track of how many
4381 	 * persistent transactions there are. We need to do this so if this
4382 	 * call is part of a failed restart_transaction, we can free it later
4383 	 */
4384 	th->t_super = sb;
4385 
4386 	return journal->j_errno;
4387 }
4388 
4389 /* Send the file system read only and refuse new transactions */
4390 void reiserfs_abort_journal(struct super_block *sb, int errno)
4391 {
4392 	struct reiserfs_journal *journal = SB_JOURNAL(sb);
4393 	if (test_bit(J_ABORTED, &journal->j_state))
4394 		return;
4395 
4396 	if (!journal->j_errno)
4397 		journal->j_errno = errno;
4398 
4399 	sb->s_flags |= SB_RDONLY;
4400 	set_bit(J_ABORTED, &journal->j_state);
4401 
4402 #ifdef CONFIG_REISERFS_CHECK
4403 	dump_stack();
4404 #endif
4405 }
4406