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1/*
2** Write ahead logging implementation copyright Chris Mason 2000
3**
4** The background commits make this code very interelated, and
5** overly complex.  I need to rethink things a bit....The major players:
6**
7** journal_begin -- call with the number of blocks you expect to log.
8**                  If the current transaction is too
9** 		    old, it will block until the current transaction is
10** 		    finished, and then start a new one.
11**		    Usually, your transaction will get joined in with
12**                  previous ones for speed.
13**
14** journal_join  -- same as journal_begin, but won't block on the current
15**                  transaction regardless of age.  Don't ever call
16**                  this.  Ever.  There are only two places it should be
17**                  called from, and they are both inside this file.
18**
19** journal_mark_dirty -- adds blocks into this transaction.  clears any flags
20**                       that might make them get sent to disk
21**                       and then marks them BH_JDirty.  Puts the buffer head
22**                       into the current transaction hash.
23**
24** journal_end -- if the current transaction is batchable, it does nothing
25**                   otherwise, it could do an async/synchronous commit, or
26**                   a full flush of all log and real blocks in the
27**                   transaction.
28**
29** flush_old_commits -- if the current transaction is too old, it is ended and
30**                      commit blocks are sent to disk.  Forces commit blocks
31**                      to disk for all backgrounded commits that have been
32**                      around too long.
33**		     -- Note, if you call this as an immediate flush from
34**		        from within kupdate, it will ignore the immediate flag
35*/
36
37#include <linux/time.h>
38#include <linux/semaphore.h>
39#include <linux/vmalloc.h>
40#include <linux/reiserfs_fs.h>
41#include <linux/kernel.h>
42#include <linux/errno.h>
43#include <linux/fcntl.h>
44#include <linux/stat.h>
45#include <linux/string.h>
46#include <linux/smp_lock.h>
47#include <linux/buffer_head.h>
48#include <linux/workqueue.h>
49#include <linux/writeback.h>
50#include <linux/blkdev.h>
51#include <linux/backing-dev.h>
52#include <linux/uaccess.h>
53#include <linux/slab.h>
54
55#include <asm/system.h>
56
57/* gets a struct reiserfs_journal_list * from a list head */
58#define JOURNAL_LIST_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
59                               j_list))
60#define JOURNAL_WORK_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
61                               j_working_list))
62
63/* the number of mounted filesystems.  This is used to decide when to
64** start and kill the commit workqueue
65*/
66static int reiserfs_mounted_fs_count;
67
68static struct workqueue_struct *commit_wq;
69
70#define JOURNAL_TRANS_HALF 1018	/* must be correct to keep the desc and commit
71				   structs at 4k */
72#define BUFNR 64		/*read ahead */
73
74/* cnode stat bits.  Move these into reiserfs_fs.h */
75
76#define BLOCK_FREED 2		/* this block was freed, and can't be written.  */
77#define BLOCK_FREED_HOLDER 3	/* this block was freed during this transaction, and can't be written */
78
79#define BLOCK_NEEDS_FLUSH 4	/* used in flush_journal_list */
80#define BLOCK_DIRTIED 5
81
82/* journal list state bits */
83#define LIST_TOUCHED 1
84#define LIST_DIRTY   2
85#define LIST_COMMIT_PENDING  4	/* someone will commit this list */
86
87/* flags for do_journal_end */
88#define FLUSH_ALL   1		/* flush commit and real blocks */
89#define COMMIT_NOW  2		/* end and commit this transaction */
90#define WAIT        4		/* wait for the log blocks to hit the disk */
91
92static int do_journal_end(struct reiserfs_transaction_handle *,
93			  struct super_block *, unsigned long nblocks,
94			  int flags);
95static int flush_journal_list(struct super_block *s,
96			      struct reiserfs_journal_list *jl, int flushall);
97static int flush_commit_list(struct super_block *s,
98			     struct reiserfs_journal_list *jl, int flushall);
99static int can_dirty(struct reiserfs_journal_cnode *cn);
100static int journal_join(struct reiserfs_transaction_handle *th,
101			struct super_block *sb, unsigned long nblocks);
102static int release_journal_dev(struct super_block *super,
103			       struct reiserfs_journal *journal);
104static int dirty_one_transaction(struct super_block *s,
105				 struct reiserfs_journal_list *jl);
106static void flush_async_commits(struct work_struct *work);
107static void queue_log_writer(struct super_block *s);
108
109/* values for join in do_journal_begin_r */
110enum {
111	JBEGIN_REG = 0,		/* regular journal begin */
112	JBEGIN_JOIN = 1,	/* join the running transaction if at all possible */
113	JBEGIN_ABORT = 2,	/* called from cleanup code, ignores aborted flag */
114};
115
116static int do_journal_begin_r(struct reiserfs_transaction_handle *th,
117			      struct super_block *sb,
118			      unsigned long nblocks, int join);
119
120static void init_journal_hash(struct super_block *sb)
121{
122	struct reiserfs_journal *journal = SB_JOURNAL(sb);
123	memset(journal->j_hash_table, 0,
124	       JOURNAL_HASH_SIZE * sizeof(struct reiserfs_journal_cnode *));
125}
126
127/*
128** clears BH_Dirty and sticks the buffer on the clean list.  Called because I can't allow refile_buffer to
129** make schedule happen after I've freed a block.  Look at remove_from_transaction and journal_mark_freed for
130** more details.
131*/
132static int reiserfs_clean_and_file_buffer(struct buffer_head *bh)
133{
134	if (bh) {
135		clear_buffer_dirty(bh);
136		clear_buffer_journal_test(bh);
137	}
138	return 0;
139}
140
141static void disable_barrier(struct super_block *s)
142{
143	REISERFS_SB(s)->s_mount_opt &= ~(1 << REISERFS_BARRIER_FLUSH);
144	printk("reiserfs: disabling flush barriers on %s\n",
145	       reiserfs_bdevname(s));
146}
147
148static struct reiserfs_bitmap_node *allocate_bitmap_node(struct super_block
149							 *sb)
150{
151	struct reiserfs_bitmap_node *bn;
152	static int id;
153
154	bn = kmalloc(sizeof(struct reiserfs_bitmap_node), GFP_NOFS);
155	if (!bn) {
156		return NULL;
157	}
158	bn->data = kzalloc(sb->s_blocksize, GFP_NOFS);
159	if (!bn->data) {
160		kfree(bn);
161		return NULL;
162	}
163	bn->id = id++;
164	INIT_LIST_HEAD(&bn->list);
165	return bn;
166}
167
168static struct reiserfs_bitmap_node *get_bitmap_node(struct super_block *sb)
169{
170	struct reiserfs_journal *journal = SB_JOURNAL(sb);
171	struct reiserfs_bitmap_node *bn = NULL;
172	struct list_head *entry = journal->j_bitmap_nodes.next;
173
174	journal->j_used_bitmap_nodes++;
175      repeat:
176
177	if (entry != &journal->j_bitmap_nodes) {
178		bn = list_entry(entry, struct reiserfs_bitmap_node, list);
179		list_del(entry);
180		memset(bn->data, 0, sb->s_blocksize);
181		journal->j_free_bitmap_nodes--;
182		return bn;
183	}
184	bn = allocate_bitmap_node(sb);
185	if (!bn) {
186		yield();
187		goto repeat;
188	}
189	return bn;
190}
191static inline void free_bitmap_node(struct super_block *sb,
192				    struct reiserfs_bitmap_node *bn)
193{
194	struct reiserfs_journal *journal = SB_JOURNAL(sb);
195	journal->j_used_bitmap_nodes--;
196	if (journal->j_free_bitmap_nodes > REISERFS_MAX_BITMAP_NODES) {
197		kfree(bn->data);
198		kfree(bn);
199	} else {
200		list_add(&bn->list, &journal->j_bitmap_nodes);
201		journal->j_free_bitmap_nodes++;
202	}
203}
204
205static void allocate_bitmap_nodes(struct super_block *sb)
206{
207	int i;
208	struct reiserfs_journal *journal = SB_JOURNAL(sb);
209	struct reiserfs_bitmap_node *bn = NULL;
210	for (i = 0; i < REISERFS_MIN_BITMAP_NODES; i++) {
211		bn = allocate_bitmap_node(sb);
212		if (bn) {
213			list_add(&bn->list, &journal->j_bitmap_nodes);
214			journal->j_free_bitmap_nodes++;
215		} else {
216			break;	/* this is ok, we'll try again when more are needed */
217		}
218	}
219}
220
221static int set_bit_in_list_bitmap(struct super_block *sb,
222				  b_blocknr_t block,
223				  struct reiserfs_list_bitmap *jb)
224{
225	unsigned int bmap_nr = block / (sb->s_blocksize << 3);
226	unsigned int bit_nr = block % (sb->s_blocksize << 3);
227
228	if (!jb->bitmaps[bmap_nr]) {
229		jb->bitmaps[bmap_nr] = get_bitmap_node(sb);
230	}
231	set_bit(bit_nr, (unsigned long *)jb->bitmaps[bmap_nr]->data);
232	return 0;
233}
234
235static void cleanup_bitmap_list(struct super_block *sb,
236				struct reiserfs_list_bitmap *jb)
237{
238	int i;
239	if (jb->bitmaps == NULL)
240		return;
241
242	for (i = 0; i < reiserfs_bmap_count(sb); i++) {
243		if (jb->bitmaps[i]) {
244			free_bitmap_node(sb, jb->bitmaps[i]);
245			jb->bitmaps[i] = NULL;
246		}
247	}
248}
249
250/*
251** only call this on FS unmount.
252*/
253static int free_list_bitmaps(struct super_block *sb,
254			     struct reiserfs_list_bitmap *jb_array)
255{
256	int i;
257	struct reiserfs_list_bitmap *jb;
258	for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
259		jb = jb_array + i;
260		jb->journal_list = NULL;
261		cleanup_bitmap_list(sb, jb);
262		vfree(jb->bitmaps);
263		jb->bitmaps = NULL;
264	}
265	return 0;
266}
267
268static int free_bitmap_nodes(struct super_block *sb)
269{
270	struct reiserfs_journal *journal = SB_JOURNAL(sb);
271	struct list_head *next = journal->j_bitmap_nodes.next;
272	struct reiserfs_bitmap_node *bn;
273
274	while (next != &journal->j_bitmap_nodes) {
275		bn = list_entry(next, struct reiserfs_bitmap_node, list);
276		list_del(next);
277		kfree(bn->data);
278		kfree(bn);
279		next = journal->j_bitmap_nodes.next;
280		journal->j_free_bitmap_nodes--;
281	}
282
283	return 0;
284}
285
286/*
287** get memory for JOURNAL_NUM_BITMAPS worth of bitmaps.
288** jb_array is the array to be filled in.
289*/
290int reiserfs_allocate_list_bitmaps(struct super_block *sb,
291				   struct reiserfs_list_bitmap *jb_array,
292				   unsigned int bmap_nr)
293{
294	int i;
295	int failed = 0;
296	struct reiserfs_list_bitmap *jb;
297	int mem = bmap_nr * sizeof(struct reiserfs_bitmap_node *);
298
299	for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
300		jb = jb_array + i;
301		jb->journal_list = NULL;
302		jb->bitmaps = vmalloc(mem);
303		if (!jb->bitmaps) {
304			reiserfs_warning(sb, "clm-2000", "unable to "
305					 "allocate bitmaps for journal lists");
306			failed = 1;
307			break;
308		}
309		memset(jb->bitmaps, 0, mem);
310	}
311	if (failed) {
312		free_list_bitmaps(sb, jb_array);
313		return -1;
314	}
315	return 0;
316}
317
318/*
319** find an available list bitmap.  If you can't find one, flush a commit list
320** and try again
321*/
322static struct reiserfs_list_bitmap *get_list_bitmap(struct super_block *sb,
323						    struct reiserfs_journal_list
324						    *jl)
325{
326	int i, j;
327	struct reiserfs_journal *journal = SB_JOURNAL(sb);
328	struct reiserfs_list_bitmap *jb = NULL;
329
330	for (j = 0; j < (JOURNAL_NUM_BITMAPS * 3); j++) {
331		i = journal->j_list_bitmap_index;
332		journal->j_list_bitmap_index = (i + 1) % JOURNAL_NUM_BITMAPS;
333		jb = journal->j_list_bitmap + i;
334		if (journal->j_list_bitmap[i].journal_list) {
335			flush_commit_list(sb,
336					  journal->j_list_bitmap[i].
337					  journal_list, 1);
338			if (!journal->j_list_bitmap[i].journal_list) {
339				break;
340			}
341		} else {
342			break;
343		}
344	}
345	if (jb->journal_list) {	/* double check to make sure if flushed correctly */
346		return NULL;
347	}
348	jb->journal_list = jl;
349	return jb;
350}
351
352/*
353** allocates a new chunk of X nodes, and links them all together as a list.
354** Uses the cnode->next and cnode->prev pointers
355** returns NULL on failure
356*/
357static struct reiserfs_journal_cnode *allocate_cnodes(int num_cnodes)
358{
359	struct reiserfs_journal_cnode *head;
360	int i;
361	if (num_cnodes <= 0) {
362		return NULL;
363	}
364	head = vmalloc(num_cnodes * sizeof(struct reiserfs_journal_cnode));
365	if (!head) {
366		return NULL;
367	}
368	memset(head, 0, num_cnodes * sizeof(struct reiserfs_journal_cnode));
369	head[0].prev = NULL;
370	head[0].next = head + 1;
371	for (i = 1; i < num_cnodes; i++) {
372		head[i].prev = head + (i - 1);
373		head[i].next = head + (i + 1);	/* if last one, overwrite it after the if */
374	}
375	head[num_cnodes - 1].next = NULL;
376	return head;
377}
378
379/*
380** pulls a cnode off the free list, or returns NULL on failure
381*/
382static struct reiserfs_journal_cnode *get_cnode(struct super_block *sb)
383{
384	struct reiserfs_journal_cnode *cn;
385	struct reiserfs_journal *journal = SB_JOURNAL(sb);
386
387	reiserfs_check_lock_depth(sb, "get_cnode");
388
389	if (journal->j_cnode_free <= 0) {
390		return NULL;
391	}
392	journal->j_cnode_used++;
393	journal->j_cnode_free--;
394	cn = journal->j_cnode_free_list;
395	if (!cn) {
396		return cn;
397	}
398	if (cn->next) {
399		cn->next->prev = NULL;
400	}
401	journal->j_cnode_free_list = cn->next;
402	memset(cn, 0, sizeof(struct reiserfs_journal_cnode));
403	return cn;
404}
405
406/*
407** returns a cnode to the free list
408*/
409static void free_cnode(struct super_block *sb,
410		       struct reiserfs_journal_cnode *cn)
411{
412	struct reiserfs_journal *journal = SB_JOURNAL(sb);
413
414	reiserfs_check_lock_depth(sb, "free_cnode");
415
416	journal->j_cnode_used--;
417	journal->j_cnode_free++;
418	/* memset(cn, 0, sizeof(struct reiserfs_journal_cnode)) ; */
419	cn->next = journal->j_cnode_free_list;
420	if (journal->j_cnode_free_list) {
421		journal->j_cnode_free_list->prev = cn;
422	}
423	cn->prev = NULL;	/* not needed with the memset, but I might kill the memset, and forget to do this */
424	journal->j_cnode_free_list = cn;
425}
426
427static void clear_prepared_bits(struct buffer_head *bh)
428{
429	clear_buffer_journal_prepared(bh);
430	clear_buffer_journal_restore_dirty(bh);
431}
432
433/* return a cnode with same dev, block number and size in table, or null if not found */
434static inline struct reiserfs_journal_cnode *get_journal_hash_dev(struct
435								  super_block
436								  *sb,
437								  struct
438								  reiserfs_journal_cnode
439								  **table,
440								  long bl)
441{
442	struct reiserfs_journal_cnode *cn;
443	cn = journal_hash(table, sb, bl);
444	while (cn) {
445		if (cn->blocknr == bl && cn->sb == sb)
446			return cn;
447		cn = cn->hnext;
448	}
449	return (struct reiserfs_journal_cnode *)0;
450}
451
452/*
453** this actually means 'can this block be reallocated yet?'.  If you set search_all, a block can only be allocated
454** if it is not in the current transaction, was not freed by the current transaction, and has no chance of ever
455** being overwritten by a replay after crashing.
456**
457** If you don't set search_all, a block can only be allocated if it is not in the current transaction.  Since deleting
458** a block removes it from the current transaction, this case should never happen.  If you don't set search_all, make
459** sure you never write the block without logging it.
460**
461** next_zero_bit is a suggestion about the next block to try for find_forward.
462** when bl is rejected because it is set in a journal list bitmap, we search
463** for the next zero bit in the bitmap that rejected bl.  Then, we return that
464** through next_zero_bit for find_forward to try.
465**
466** Just because we return something in next_zero_bit does not mean we won't
467** reject it on the next call to reiserfs_in_journal
468**
469*/
470int reiserfs_in_journal(struct super_block *sb,
471			unsigned int bmap_nr, int bit_nr, int search_all,
472			b_blocknr_t * next_zero_bit)
473{
474	struct reiserfs_journal *journal = SB_JOURNAL(sb);
475	struct reiserfs_journal_cnode *cn;
476	struct reiserfs_list_bitmap *jb;
477	int i;
478	unsigned long bl;
479
480	*next_zero_bit = 0;	/* always start this at zero. */
481
482	PROC_INFO_INC(sb, journal.in_journal);
483	/* If we aren't doing a search_all, this is a metablock, and it will be logged before use.
484	 ** if we crash before the transaction that freed it commits,  this transaction won't
485	 ** have committed either, and the block will never be written
486	 */
487	if (search_all) {
488		for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
489			PROC_INFO_INC(sb, journal.in_journal_bitmap);
490			jb = journal->j_list_bitmap + i;
491			if (jb->journal_list && jb->bitmaps[bmap_nr] &&
492			    test_bit(bit_nr,
493				     (unsigned long *)jb->bitmaps[bmap_nr]->
494				     data)) {
495				*next_zero_bit =
496				    find_next_zero_bit((unsigned long *)
497						       (jb->bitmaps[bmap_nr]->
498							data),
499						       sb->s_blocksize << 3,
500						       bit_nr + 1);
501				return 1;
502			}
503		}
504	}
505
506	bl = bmap_nr * (sb->s_blocksize << 3) + bit_nr;
507	/* is it in any old transactions? */
508	if (search_all
509	    && (cn =
510		get_journal_hash_dev(sb, journal->j_list_hash_table, bl))) {
511		return 1;
512	}
513
514	/* is it in the current transaction.  This should never happen */
515	if ((cn = get_journal_hash_dev(sb, journal->j_hash_table, bl))) {
516		BUG();
517		return 1;
518	}
519
520	PROC_INFO_INC(sb, journal.in_journal_reusable);
521	/* safe for reuse */
522	return 0;
523}
524
525/* insert cn into table
526*/
527static inline void insert_journal_hash(struct reiserfs_journal_cnode **table,
528				       struct reiserfs_journal_cnode *cn)
529{
530	struct reiserfs_journal_cnode *cn_orig;
531
532	cn_orig = journal_hash(table, cn->sb, cn->blocknr);
533	cn->hnext = cn_orig;
534	cn->hprev = NULL;
535	if (cn_orig) {
536		cn_orig->hprev = cn;
537	}
538	journal_hash(table, cn->sb, cn->blocknr) = cn;
539}
540
541/* lock the current transaction */
542static inline void lock_journal(struct super_block *sb)
543{
544	PROC_INFO_INC(sb, journal.lock_journal);
545
546	reiserfs_mutex_lock_safe(&SB_JOURNAL(sb)->j_mutex, sb);
547}
548
549/* unlock the current transaction */
550static inline void unlock_journal(struct super_block *sb)
551{
552	mutex_unlock(&SB_JOURNAL(sb)->j_mutex);
553}
554
555static inline void get_journal_list(struct reiserfs_journal_list *jl)
556{
557	jl->j_refcount++;
558}
559
560static inline void put_journal_list(struct super_block *s,
561				    struct reiserfs_journal_list *jl)
562{
563	if (jl->j_refcount < 1) {
564		reiserfs_panic(s, "journal-2", "trans id %u, refcount at %d",
565			       jl->j_trans_id, jl->j_refcount);
566	}
567	if (--jl->j_refcount == 0)
568		kfree(jl);
569}
570
571/*
572** this used to be much more involved, and I'm keeping it just in case things get ugly again.
573** it gets called by flush_commit_list, and cleans up any data stored about blocks freed during a
574** transaction.
575*/
576static void cleanup_freed_for_journal_list(struct super_block *sb,
577					   struct reiserfs_journal_list *jl)
578{
579
580	struct reiserfs_list_bitmap *jb = jl->j_list_bitmap;
581	if (jb) {
582		cleanup_bitmap_list(sb, jb);
583	}
584	jl->j_list_bitmap->journal_list = NULL;
585	jl->j_list_bitmap = NULL;
586}
587
588static int journal_list_still_alive(struct super_block *s,
589				    unsigned int trans_id)
590{
591	struct reiserfs_journal *journal = SB_JOURNAL(s);
592	struct list_head *entry = &journal->j_journal_list;
593	struct reiserfs_journal_list *jl;
594
595	if (!list_empty(entry)) {
596		jl = JOURNAL_LIST_ENTRY(entry->next);
597		if (jl->j_trans_id <= trans_id) {
598			return 1;
599		}
600	}
601	return 0;
602}
603
604/*
605 * If page->mapping was null, we failed to truncate this page for
606 * some reason.  Most likely because it was truncated after being
607 * logged via data=journal.
608 *
609 * This does a check to see if the buffer belongs to one of these
610 * lost pages before doing the final put_bh.  If page->mapping was
611 * null, it tries to free buffers on the page, which should make the
612 * final page_cache_release drop the page from the lru.
613 */
614static void release_buffer_page(struct buffer_head *bh)
615{
616	struct page *page = bh->b_page;
617	if (!page->mapping && trylock_page(page)) {
618		page_cache_get(page);
619		put_bh(bh);
620		if (!page->mapping)
621			try_to_free_buffers(page);
622		unlock_page(page);
623		page_cache_release(page);
624	} else {
625		put_bh(bh);
626	}
627}
628
629static void reiserfs_end_buffer_io_sync(struct buffer_head *bh, int uptodate)
630{
631	char b[BDEVNAME_SIZE];
632
633	if (buffer_journaled(bh)) {
634		reiserfs_warning(NULL, "clm-2084",
635				 "pinned buffer %lu:%s sent to disk",
636				 bh->b_blocknr, bdevname(bh->b_bdev, b));
637	}
638	if (uptodate)
639		set_buffer_uptodate(bh);
640	else
641		clear_buffer_uptodate(bh);
642
643	unlock_buffer(bh);
644	release_buffer_page(bh);
645}
646
647static void reiserfs_end_ordered_io(struct buffer_head *bh, int uptodate)
648{
649	if (uptodate)
650		set_buffer_uptodate(bh);
651	else
652		clear_buffer_uptodate(bh);
653	unlock_buffer(bh);
654	put_bh(bh);
655}
656
657static void submit_logged_buffer(struct buffer_head *bh)
658{
659	get_bh(bh);
660	bh->b_end_io = reiserfs_end_buffer_io_sync;
661	clear_buffer_journal_new(bh);
662	clear_buffer_dirty(bh);
663	if (!test_clear_buffer_journal_test(bh))
664		BUG();
665	if (!buffer_uptodate(bh))
666		BUG();
667	submit_bh(WRITE, bh);
668}
669
670static void submit_ordered_buffer(struct buffer_head *bh)
671{
672	get_bh(bh);
673	bh->b_end_io = reiserfs_end_ordered_io;
674	clear_buffer_dirty(bh);
675	if (!buffer_uptodate(bh))
676		BUG();
677	submit_bh(WRITE, bh);
678}
679
680static int submit_barrier_buffer(struct buffer_head *bh)
681{
682	get_bh(bh);
683	bh->b_end_io = reiserfs_end_ordered_io;
684	clear_buffer_dirty(bh);
685	if (!buffer_uptodate(bh))
686		BUG();
687	return submit_bh(WRITE_BARRIER, bh);
688}
689
690static void check_barrier_completion(struct super_block *s,
691				     struct buffer_head *bh)
692{
693	if (buffer_eopnotsupp(bh)) {
694		clear_buffer_eopnotsupp(bh);
695		disable_barrier(s);
696		set_buffer_uptodate(bh);
697		set_buffer_dirty(bh);
698		reiserfs_write_unlock(s);
699		sync_dirty_buffer(bh);
700		reiserfs_write_lock(s);
701	}
702}
703
704#define CHUNK_SIZE 32
705struct buffer_chunk {
706	struct buffer_head *bh[CHUNK_SIZE];
707	int nr;
708};
709
710static void write_chunk(struct buffer_chunk *chunk)
711{
712	int i;
713	get_fs_excl();
714	for (i = 0; i < chunk->nr; i++) {
715		submit_logged_buffer(chunk->bh[i]);
716	}
717	chunk->nr = 0;
718	put_fs_excl();
719}
720
721static void write_ordered_chunk(struct buffer_chunk *chunk)
722{
723	int i;
724	get_fs_excl();
725	for (i = 0; i < chunk->nr; i++) {
726		submit_ordered_buffer(chunk->bh[i]);
727	}
728	chunk->nr = 0;
729	put_fs_excl();
730}
731
732static int add_to_chunk(struct buffer_chunk *chunk, struct buffer_head *bh,
733			spinlock_t * lock, void (fn) (struct buffer_chunk *))
734{
735	int ret = 0;
736	BUG_ON(chunk->nr >= CHUNK_SIZE);
737	chunk->bh[chunk->nr++] = bh;
738	if (chunk->nr >= CHUNK_SIZE) {
739		ret = 1;
740		if (lock)
741			spin_unlock(lock);
742		fn(chunk);
743		if (lock)
744			spin_lock(lock);
745	}
746	return ret;
747}
748
749static atomic_t nr_reiserfs_jh = ATOMIC_INIT(0);
750static struct reiserfs_jh *alloc_jh(void)
751{
752	struct reiserfs_jh *jh;
753	while (1) {
754		jh = kmalloc(sizeof(*jh), GFP_NOFS);
755		if (jh) {
756			atomic_inc(&nr_reiserfs_jh);
757			return jh;
758		}
759		yield();
760	}
761}
762
763/*
764 * we want to free the jh when the buffer has been written
765 * and waited on
766 */
767void reiserfs_free_jh(struct buffer_head *bh)
768{
769	struct reiserfs_jh *jh;
770
771	jh = bh->b_private;
772	if (jh) {
773		bh->b_private = NULL;
774		jh->bh = NULL;
775		list_del_init(&jh->list);
776		kfree(jh);
777		if (atomic_read(&nr_reiserfs_jh) <= 0)
778			BUG();
779		atomic_dec(&nr_reiserfs_jh);
780		put_bh(bh);
781	}
782}
783
784static inline int __add_jh(struct reiserfs_journal *j, struct buffer_head *bh,
785			   int tail)
786{
787	struct reiserfs_jh *jh;
788
789	if (bh->b_private) {
790		spin_lock(&j->j_dirty_buffers_lock);
791		if (!bh->b_private) {
792			spin_unlock(&j->j_dirty_buffers_lock);
793			goto no_jh;
794		}
795		jh = bh->b_private;
796		list_del_init(&jh->list);
797	} else {
798	      no_jh:
799		get_bh(bh);
800		jh = alloc_jh();
801		spin_lock(&j->j_dirty_buffers_lock);
802		/* buffer must be locked for __add_jh, should be able to have
803		 * two adds at the same time
804		 */
805		BUG_ON(bh->b_private);
806		jh->bh = bh;
807		bh->b_private = jh;
808	}
809	jh->jl = j->j_current_jl;
810	if (tail)
811		list_add_tail(&jh->list, &jh->jl->j_tail_bh_list);
812	else {
813		list_add_tail(&jh->list, &jh->jl->j_bh_list);
814	}
815	spin_unlock(&j->j_dirty_buffers_lock);
816	return 0;
817}
818
819int reiserfs_add_tail_list(struct inode *inode, struct buffer_head *bh)
820{
821	return __add_jh(SB_JOURNAL(inode->i_sb), bh, 1);
822}
823int reiserfs_add_ordered_list(struct inode *inode, struct buffer_head *bh)
824{
825	return __add_jh(SB_JOURNAL(inode->i_sb), bh, 0);
826}
827
828#define JH_ENTRY(l) list_entry((l), struct reiserfs_jh, list)
829static int write_ordered_buffers(spinlock_t * lock,
830				 struct reiserfs_journal *j,
831				 struct reiserfs_journal_list *jl,
832				 struct list_head *list)
833{
834	struct buffer_head *bh;
835	struct reiserfs_jh *jh;
836	int ret = j->j_errno;
837	struct buffer_chunk chunk;
838	struct list_head tmp;
839	INIT_LIST_HEAD(&tmp);
840
841	chunk.nr = 0;
842	spin_lock(lock);
843	while (!list_empty(list)) {
844		jh = JH_ENTRY(list->next);
845		bh = jh->bh;
846		get_bh(bh);
847		if (!trylock_buffer(bh)) {
848			if (!buffer_dirty(bh)) {
849				list_move(&jh->list, &tmp);
850				goto loop_next;
851			}
852			spin_unlock(lock);
853			if (chunk.nr)
854				write_ordered_chunk(&chunk);
855			wait_on_buffer(bh);
856			cond_resched();
857			spin_lock(lock);
858			goto loop_next;
859		}
860		/* in theory, dirty non-uptodate buffers should never get here,
861		 * but the upper layer io error paths still have a few quirks.
862		 * Handle them here as gracefully as we can
863		 */
864		if (!buffer_uptodate(bh) && buffer_dirty(bh)) {
865			clear_buffer_dirty(bh);
866			ret = -EIO;
867		}
868		if (buffer_dirty(bh)) {
869			list_move(&jh->list, &tmp);
870			add_to_chunk(&chunk, bh, lock, write_ordered_chunk);
871		} else {
872			reiserfs_free_jh(bh);
873			unlock_buffer(bh);
874		}
875	      loop_next:
876		put_bh(bh);
877		cond_resched_lock(lock);
878	}
879	if (chunk.nr) {
880		spin_unlock(lock);
881		write_ordered_chunk(&chunk);
882		spin_lock(lock);
883	}
884	while (!list_empty(&tmp)) {
885		jh = JH_ENTRY(tmp.prev);
886		bh = jh->bh;
887		get_bh(bh);
888		reiserfs_free_jh(bh);
889
890		if (buffer_locked(bh)) {
891			spin_unlock(lock);
892			wait_on_buffer(bh);
893			spin_lock(lock);
894		}
895		if (!buffer_uptodate(bh)) {
896			ret = -EIO;
897		}
898		/* ugly interaction with invalidatepage here.
899		 * reiserfs_invalidate_page will pin any buffer that has a valid
900		 * journal head from an older transaction.  If someone else sets
901		 * our buffer dirty after we write it in the first loop, and
902		 * then someone truncates the page away, nobody will ever write
903		 * the buffer. We're safe if we write the page one last time
904		 * after freeing the journal header.
905		 */
906		if (buffer_dirty(bh) && unlikely(bh->b_page->mapping == NULL)) {
907			spin_unlock(lock);
908			ll_rw_block(WRITE, 1, &bh);
909			spin_lock(lock);
910		}
911		put_bh(bh);
912		cond_resched_lock(lock);
913	}
914	spin_unlock(lock);
915	return ret;
916}
917
918static int flush_older_commits(struct super_block *s,
919			       struct reiserfs_journal_list *jl)
920{
921	struct reiserfs_journal *journal = SB_JOURNAL(s);
922	struct reiserfs_journal_list *other_jl;
923	struct reiserfs_journal_list *first_jl;
924	struct list_head *entry;
925	unsigned int trans_id = jl->j_trans_id;
926	unsigned int other_trans_id;
927	unsigned int first_trans_id;
928
929      find_first:
930	/*
931	 * first we walk backwards to find the oldest uncommitted transation
932	 */
933	first_jl = jl;
934	entry = jl->j_list.prev;
935	while (1) {
936		other_jl = JOURNAL_LIST_ENTRY(entry);
937		if (entry == &journal->j_journal_list ||
938		    atomic_read(&other_jl->j_older_commits_done))
939			break;
940
941		first_jl = other_jl;
942		entry = other_jl->j_list.prev;
943	}
944
945	/* if we didn't find any older uncommitted transactions, return now */
946	if (first_jl == jl) {
947		return 0;
948	}
949
950	first_trans_id = first_jl->j_trans_id;
951
952	entry = &first_jl->j_list;
953	while (1) {
954		other_jl = JOURNAL_LIST_ENTRY(entry);
955		other_trans_id = other_jl->j_trans_id;
956
957		if (other_trans_id < trans_id) {
958			if (atomic_read(&other_jl->j_commit_left) != 0) {
959				flush_commit_list(s, other_jl, 0);
960
961				/* list we were called with is gone, return */
962				if (!journal_list_still_alive(s, trans_id))
963					return 1;
964
965				/* the one we just flushed is gone, this means all
966				 * older lists are also gone, so first_jl is no longer
967				 * valid either.  Go back to the beginning.
968				 */
969				if (!journal_list_still_alive
970				    (s, other_trans_id)) {
971					goto find_first;
972				}
973			}
974			entry = entry->next;
975			if (entry == &journal->j_journal_list)
976				return 0;
977		} else {
978			return 0;
979		}
980	}
981	return 0;
982}
983
984static int reiserfs_async_progress_wait(struct super_block *s)
985{
986	struct reiserfs_journal *j = SB_JOURNAL(s);
987
988	if (atomic_read(&j->j_async_throttle)) {
989		reiserfs_write_unlock(s);
990		congestion_wait(BLK_RW_ASYNC, HZ / 10);
991		reiserfs_write_lock(s);
992	}
993
994	return 0;
995}
996
997/*
998** if this journal list still has commit blocks unflushed, send them to disk.
999**
1000** log areas must be flushed in order (transaction 2 can't commit before transaction 1)
1001** Before the commit block can by written, every other log block must be safely on disk
1002**
1003*/
1004static int flush_commit_list(struct super_block *s,
1005			     struct reiserfs_journal_list *jl, int flushall)
1006{
1007	int i;
1008	b_blocknr_t bn;
1009	struct buffer_head *tbh = NULL;
1010	unsigned int trans_id = jl->j_trans_id;
1011	struct reiserfs_journal *journal = SB_JOURNAL(s);
1012	int barrier = 0;
1013	int retval = 0;
1014	int write_len;
1015
1016	reiserfs_check_lock_depth(s, "flush_commit_list");
1017
1018	if (atomic_read(&jl->j_older_commits_done)) {
1019		return 0;
1020	}
1021
1022	get_fs_excl();
1023
1024	/* before we can put our commit blocks on disk, we have to make sure everyone older than
1025	 ** us is on disk too
1026	 */
1027	BUG_ON(jl->j_len <= 0);
1028	BUG_ON(trans_id == journal->j_trans_id);
1029
1030	get_journal_list(jl);
1031	if (flushall) {
1032		if (flush_older_commits(s, jl) == 1) {
1033			/* list disappeared during flush_older_commits.  return */
1034			goto put_jl;
1035		}
1036	}
1037
1038	/* make sure nobody is trying to flush this one at the same time */
1039	reiserfs_mutex_lock_safe(&jl->j_commit_mutex, s);
1040
1041	if (!journal_list_still_alive(s, trans_id)) {
1042		mutex_unlock(&jl->j_commit_mutex);
1043		goto put_jl;
1044	}
1045	BUG_ON(jl->j_trans_id == 0);
1046
1047	/* this commit is done, exit */
1048	if (atomic_read(&(jl->j_commit_left)) <= 0) {
1049		if (flushall) {
1050			atomic_set(&(jl->j_older_commits_done), 1);
1051		}
1052		mutex_unlock(&jl->j_commit_mutex);
1053		goto put_jl;
1054	}
1055
1056	if (!list_empty(&jl->j_bh_list)) {
1057		int ret;
1058
1059		/*
1060		 * We might sleep in numerous places inside
1061		 * write_ordered_buffers. Relax the write lock.
1062		 */
1063		reiserfs_write_unlock(s);
1064		ret = write_ordered_buffers(&journal->j_dirty_buffers_lock,
1065					    journal, jl, &jl->j_bh_list);
1066		if (ret < 0 && retval == 0)
1067			retval = ret;
1068		reiserfs_write_lock(s);
1069	}
1070	BUG_ON(!list_empty(&jl->j_bh_list));
1071	/*
1072	 * for the description block and all the log blocks, submit any buffers
1073	 * that haven't already reached the disk.  Try to write at least 256
1074	 * log blocks. later on, we will only wait on blocks that correspond
1075	 * to this transaction, but while we're unplugging we might as well
1076	 * get a chunk of data on there.
1077	 */
1078	atomic_inc(&journal->j_async_throttle);
1079	write_len = jl->j_len + 1;
1080	if (write_len < 256)
1081		write_len = 256;
1082	for (i = 0 ; i < write_len ; i++) {
1083		bn = SB_ONDISK_JOURNAL_1st_BLOCK(s) + (jl->j_start + i) %
1084		    SB_ONDISK_JOURNAL_SIZE(s);
1085		tbh = journal_find_get_block(s, bn);
1086		if (tbh) {
1087			if (buffer_dirty(tbh)) {
1088		            reiserfs_write_unlock(s);
1089			    ll_rw_block(WRITE, 1, &tbh);
1090			    reiserfs_write_lock(s);
1091			}
1092			put_bh(tbh) ;
1093		}
1094	}
1095	atomic_dec(&journal->j_async_throttle);
1096
1097	/* We're skipping the commit if there's an error */
1098	if (retval || reiserfs_is_journal_aborted(journal))
1099		barrier = 0;
1100
1101	/* wait on everything written so far before writing the commit
1102	 * if we are in barrier mode, send the commit down now
1103	 */
1104	barrier = reiserfs_barrier_flush(s);
1105	if (barrier) {
1106		int ret;
1107		lock_buffer(jl->j_commit_bh);
1108		ret = submit_barrier_buffer(jl->j_commit_bh);
1109		if (ret == -EOPNOTSUPP) {
1110			set_buffer_uptodate(jl->j_commit_bh);
1111			disable_barrier(s);
1112			barrier = 0;
1113		}
1114	}
1115	for (i = 0; i < (jl->j_len + 1); i++) {
1116		bn = SB_ONDISK_JOURNAL_1st_BLOCK(s) +
1117		    (jl->j_start + i) % SB_ONDISK_JOURNAL_SIZE(s);
1118		tbh = journal_find_get_block(s, bn);
1119
1120		reiserfs_write_unlock(s);
1121		wait_on_buffer(tbh);
1122		reiserfs_write_lock(s);
1123		// since we're using ll_rw_blk above, it might have skipped over
1124		// a locked buffer.  Double check here
1125		//
1126		/* redundant, sync_dirty_buffer() checks */
1127		if (buffer_dirty(tbh)) {
1128			reiserfs_write_unlock(s);
1129			sync_dirty_buffer(tbh);
1130			reiserfs_write_lock(s);
1131		}
1132		if (unlikely(!buffer_uptodate(tbh))) {
1133#ifdef CONFIG_REISERFS_CHECK
1134			reiserfs_warning(s, "journal-601",
1135					 "buffer write failed");
1136#endif
1137			retval = -EIO;
1138		}
1139		put_bh(tbh);	/* once for journal_find_get_block */
1140		put_bh(tbh);	/* once due to original getblk in do_journal_end */
1141		atomic_dec(&(jl->j_commit_left));
1142	}
1143
1144	BUG_ON(atomic_read(&(jl->j_commit_left)) != 1);
1145
1146	if (!barrier) {
1147		/* If there was a write error in the journal - we can't commit
1148		 * this transaction - it will be invalid and, if successful,
1149		 * will just end up propagating the write error out to
1150		 * the file system. */
1151		if (likely(!retval && !reiserfs_is_journal_aborted (journal))) {
1152			if (buffer_dirty(jl->j_commit_bh))
1153				BUG();
1154			mark_buffer_dirty(jl->j_commit_bh) ;
1155			reiserfs_write_unlock(s);
1156			sync_dirty_buffer(jl->j_commit_bh) ;
1157			reiserfs_write_lock(s);
1158		}
1159	} else {
1160		reiserfs_write_unlock(s);
1161		wait_on_buffer(jl->j_commit_bh);
1162		reiserfs_write_lock(s);
1163	}
1164
1165	check_barrier_completion(s, jl->j_commit_bh);
1166
1167	/* If there was a write error in the journal - we can't commit this
1168	 * transaction - it will be invalid and, if successful, will just end
1169	 * up propagating the write error out to the filesystem. */
1170	if (unlikely(!buffer_uptodate(jl->j_commit_bh))) {
1171#ifdef CONFIG_REISERFS_CHECK
1172		reiserfs_warning(s, "journal-615", "buffer write failed");
1173#endif
1174		retval = -EIO;
1175	}
1176	bforget(jl->j_commit_bh);
1177	if (journal->j_last_commit_id != 0 &&
1178	    (jl->j_trans_id - journal->j_last_commit_id) != 1) {
1179		reiserfs_warning(s, "clm-2200", "last commit %lu, current %lu",
1180				 journal->j_last_commit_id, jl->j_trans_id);
1181	}
1182	journal->j_last_commit_id = jl->j_trans_id;
1183
1184	/* now, every commit block is on the disk.  It is safe to allow blocks freed during this transaction to be reallocated */
1185	cleanup_freed_for_journal_list(s, jl);
1186
1187	retval = retval ? retval : journal->j_errno;
1188
1189	/* mark the metadata dirty */
1190	if (!retval)
1191		dirty_one_transaction(s, jl);
1192	atomic_dec(&(jl->j_commit_left));
1193
1194	if (flushall) {
1195		atomic_set(&(jl->j_older_commits_done), 1);
1196	}
1197	mutex_unlock(&jl->j_commit_mutex);
1198      put_jl:
1199	put_journal_list(s, jl);
1200
1201	if (retval)
1202		reiserfs_abort(s, retval, "Journal write error in %s",
1203			       __func__);
1204	put_fs_excl();
1205	return retval;
1206}
1207
1208/*
1209** flush_journal_list frequently needs to find a newer transaction for a given block.  This does that, or
1210** returns NULL if it can't find anything
1211*/
1212static struct reiserfs_journal_list *find_newer_jl_for_cn(struct
1213							  reiserfs_journal_cnode
1214							  *cn)
1215{
1216	struct super_block *sb = cn->sb;
1217	b_blocknr_t blocknr = cn->blocknr;
1218
1219	cn = cn->hprev;
1220	while (cn) {
1221		if (cn->sb == sb && cn->blocknr == blocknr && cn->jlist) {
1222			return cn->jlist;
1223		}
1224		cn = cn->hprev;
1225	}
1226	return NULL;
1227}
1228
1229static int newer_jl_done(struct reiserfs_journal_cnode *cn)
1230{
1231	struct super_block *sb = cn->sb;
1232	b_blocknr_t blocknr = cn->blocknr;
1233
1234	cn = cn->hprev;
1235	while (cn) {
1236		if (cn->sb == sb && cn->blocknr == blocknr && cn->jlist &&
1237		    atomic_read(&cn->jlist->j_commit_left) != 0)
1238				    return 0;
1239		cn = cn->hprev;
1240	}
1241	return 1;
1242}
1243
1244static void remove_journal_hash(struct super_block *,
1245				struct reiserfs_journal_cnode **,
1246				struct reiserfs_journal_list *, unsigned long,
1247				int);
1248
1249/*
1250** once all the real blocks have been flushed, it is safe to remove them from the
1251** journal list for this transaction.  Aside from freeing the cnode, this also allows the
1252** block to be reallocated for data blocks if it had been deleted.
1253*/
1254static void remove_all_from_journal_list(struct super_block *sb,
1255					 struct reiserfs_journal_list *jl,
1256					 int debug)
1257{
1258	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1259	struct reiserfs_journal_cnode *cn, *last;
1260	cn = jl->j_realblock;
1261
1262	/* which is better, to lock once around the whole loop, or
1263	 ** to lock for each call to remove_journal_hash?
1264	 */
1265	while (cn) {
1266		if (cn->blocknr != 0) {
1267			if (debug) {
1268				reiserfs_warning(sb, "reiserfs-2201",
1269						 "block %u, bh is %d, state %ld",
1270						 cn->blocknr, cn->bh ? 1 : 0,
1271						 cn->state);
1272			}
1273			cn->state = 0;
1274			remove_journal_hash(sb, journal->j_list_hash_table,
1275					    jl, cn->blocknr, 1);
1276		}
1277		last = cn;
1278		cn = cn->next;
1279		free_cnode(sb, last);
1280	}
1281	jl->j_realblock = NULL;
1282}
1283
1284/*
1285** if this timestamp is greater than the timestamp we wrote last to the header block, write it to the header block.
1286** once this is done, I can safely say the log area for this transaction won't ever be replayed, and I can start
1287** releasing blocks in this transaction for reuse as data blocks.
1288** called by flush_journal_list, before it calls remove_all_from_journal_list
1289**
1290*/
1291static int _update_journal_header_block(struct super_block *sb,
1292					unsigned long offset,
1293					unsigned int trans_id)
1294{
1295	struct reiserfs_journal_header *jh;
1296	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1297
1298	if (reiserfs_is_journal_aborted(journal))
1299		return -EIO;
1300
1301	if (trans_id >= journal->j_last_flush_trans_id) {
1302		if (buffer_locked((journal->j_header_bh))) {
1303			reiserfs_write_unlock(sb);
1304			wait_on_buffer((journal->j_header_bh));
1305			reiserfs_write_lock(sb);
1306			if (unlikely(!buffer_uptodate(journal->j_header_bh))) {
1307#ifdef CONFIG_REISERFS_CHECK
1308				reiserfs_warning(sb, "journal-699",
1309						 "buffer write failed");
1310#endif
1311				return -EIO;
1312			}
1313		}
1314		journal->j_last_flush_trans_id = trans_id;
1315		journal->j_first_unflushed_offset = offset;
1316		jh = (struct reiserfs_journal_header *)(journal->j_header_bh->
1317							b_data);
1318		jh->j_last_flush_trans_id = cpu_to_le32(trans_id);
1319		jh->j_first_unflushed_offset = cpu_to_le32(offset);
1320		jh->j_mount_id = cpu_to_le32(journal->j_mount_id);
1321
1322		if (reiserfs_barrier_flush(sb)) {
1323			int ret;
1324			lock_buffer(journal->j_header_bh);
1325			ret = submit_barrier_buffer(journal->j_header_bh);
1326			if (ret == -EOPNOTSUPP) {
1327				set_buffer_uptodate(journal->j_header_bh);
1328				disable_barrier(sb);
1329				goto sync;
1330			}
1331			reiserfs_write_unlock(sb);
1332			wait_on_buffer(journal->j_header_bh);
1333			reiserfs_write_lock(sb);
1334			check_barrier_completion(sb, journal->j_header_bh);
1335		} else {
1336		      sync:
1337			set_buffer_dirty(journal->j_header_bh);
1338			reiserfs_write_unlock(sb);
1339			sync_dirty_buffer(journal->j_header_bh);
1340			reiserfs_write_lock(sb);
1341		}
1342		if (!buffer_uptodate(journal->j_header_bh)) {
1343			reiserfs_warning(sb, "journal-837",
1344					 "IO error during journal replay");
1345			return -EIO;
1346		}
1347	}
1348	return 0;
1349}
1350
1351static int update_journal_header_block(struct super_block *sb,
1352				       unsigned long offset,
1353				       unsigned int trans_id)
1354{
1355	return _update_journal_header_block(sb, offset, trans_id);
1356}
1357
1358/*
1359** flush any and all journal lists older than you are
1360** can only be called from flush_journal_list
1361*/
1362static int flush_older_journal_lists(struct super_block *sb,
1363				     struct reiserfs_journal_list *jl)
1364{
1365	struct list_head *entry;
1366	struct reiserfs_journal_list *other_jl;
1367	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1368	unsigned int trans_id = jl->j_trans_id;
1369
1370	/* we know we are the only ones flushing things, no extra race
1371	 * protection is required.
1372	 */
1373      restart:
1374	entry = journal->j_journal_list.next;
1375	/* Did we wrap? */
1376	if (entry == &journal->j_journal_list)
1377		return 0;
1378	other_jl = JOURNAL_LIST_ENTRY(entry);
1379	if (other_jl->j_trans_id < trans_id) {
1380		BUG_ON(other_jl->j_refcount <= 0);
1381		/* do not flush all */
1382		flush_journal_list(sb, other_jl, 0);
1383
1384		/* other_jl is now deleted from the list */
1385		goto restart;
1386	}
1387	return 0;
1388}
1389
1390static void del_from_work_list(struct super_block *s,
1391			       struct reiserfs_journal_list *jl)
1392{
1393	struct reiserfs_journal *journal = SB_JOURNAL(s);
1394	if (!list_empty(&jl->j_working_list)) {
1395		list_del_init(&jl->j_working_list);
1396		journal->j_num_work_lists--;
1397	}
1398}
1399
1400/* flush a journal list, both commit and real blocks
1401**
1402** always set flushall to 1, unless you are calling from inside
1403** flush_journal_list
1404**
1405** IMPORTANT.  This can only be called while there are no journal writers,
1406** and the journal is locked.  That means it can only be called from
1407** do_journal_end, or by journal_release
1408*/
1409static int flush_journal_list(struct super_block *s,
1410			      struct reiserfs_journal_list *jl, int flushall)
1411{
1412	struct reiserfs_journal_list *pjl;
1413	struct reiserfs_journal_cnode *cn, *last;
1414	int count;
1415	int was_jwait = 0;
1416	int was_dirty = 0;
1417	struct buffer_head *saved_bh;
1418	unsigned long j_len_saved = jl->j_len;
1419	struct reiserfs_journal *journal = SB_JOURNAL(s);
1420	int err = 0;
1421
1422	BUG_ON(j_len_saved <= 0);
1423
1424	if (atomic_read(&journal->j_wcount) != 0) {
1425		reiserfs_warning(s, "clm-2048", "called with wcount %d",
1426				 atomic_read(&journal->j_wcount));
1427	}
1428	BUG_ON(jl->j_trans_id == 0);
1429
1430	/* if flushall == 0, the lock is already held */
1431	if (flushall) {
1432		reiserfs_mutex_lock_safe(&journal->j_flush_mutex, s);
1433	} else if (mutex_trylock(&journal->j_flush_mutex)) {
1434		BUG();
1435	}
1436
1437	count = 0;
1438	if (j_len_saved > journal->j_trans_max) {
1439		reiserfs_panic(s, "journal-715", "length is %lu, trans id %lu",
1440			       j_len_saved, jl->j_trans_id);
1441		return 0;
1442	}
1443
1444	get_fs_excl();
1445
1446	/* if all the work is already done, get out of here */
1447	if (atomic_read(&(jl->j_nonzerolen)) <= 0 &&
1448	    atomic_read(&(jl->j_commit_left)) <= 0) {
1449		goto flush_older_and_return;
1450	}
1451
1452	/* start by putting the commit list on disk.  This will also flush
1453	 ** the commit lists of any olders transactions
1454	 */
1455	flush_commit_list(s, jl, 1);
1456
1457	if (!(jl->j_state & LIST_DIRTY)
1458	    && !reiserfs_is_journal_aborted(journal))
1459		BUG();
1460
1461	/* are we done now? */
1462	if (atomic_read(&(jl->j_nonzerolen)) <= 0 &&
1463	    atomic_read(&(jl->j_commit_left)) <= 0) {
1464		goto flush_older_and_return;
1465	}
1466
1467	/* loop through each cnode, see if we need to write it,
1468	 ** or wait on a more recent transaction, or just ignore it
1469	 */
1470	if (atomic_read(&(journal->j_wcount)) != 0) {
1471		reiserfs_panic(s, "journal-844", "journal list is flushing, "
1472			       "wcount is not 0");
1473	}
1474	cn = jl->j_realblock;
1475	while (cn) {
1476		was_jwait = 0;
1477		was_dirty = 0;
1478		saved_bh = NULL;
1479		/* blocknr of 0 is no longer in the hash, ignore it */
1480		if (cn->blocknr == 0) {
1481			goto free_cnode;
1482		}
1483
1484		/* This transaction failed commit. Don't write out to the disk */
1485		if (!(jl->j_state & LIST_DIRTY))
1486			goto free_cnode;
1487
1488		pjl = find_newer_jl_for_cn(cn);
1489		/* the order is important here.  We check pjl to make sure we
1490		 ** don't clear BH_JDirty_wait if we aren't the one writing this
1491		 ** block to disk
1492		 */
1493		if (!pjl && cn->bh) {
1494			saved_bh = cn->bh;
1495
1496			/* we do this to make sure nobody releases the buffer while
1497			 ** we are working with it
1498			 */
1499			get_bh(saved_bh);
1500
1501			if (buffer_journal_dirty(saved_bh)) {
1502				BUG_ON(!can_dirty(cn));
1503				was_jwait = 1;
1504				was_dirty = 1;
1505			} else if (can_dirty(cn)) {
1506				/* everything with !pjl && jwait should be writable */
1507				BUG();
1508			}
1509		}
1510
1511		/* if someone has this block in a newer transaction, just make
1512		 ** sure they are committed, and don't try writing it to disk
1513		 */
1514		if (pjl) {
1515			if (atomic_read(&pjl->j_commit_left))
1516				flush_commit_list(s, pjl, 1);
1517			goto free_cnode;
1518		}
1519
1520		/* bh == NULL when the block got to disk on its own, OR,
1521		 ** the block got freed in a future transaction
1522		 */
1523		if (saved_bh == NULL) {
1524			goto free_cnode;
1525		}
1526
1527		/* this should never happen.  kupdate_one_transaction has this list
1528		 ** locked while it works, so we should never see a buffer here that
1529		 ** is not marked JDirty_wait
1530		 */
1531		if ((!was_jwait) && !buffer_locked(saved_bh)) {
1532			reiserfs_warning(s, "journal-813",
1533					 "BAD! buffer %llu %cdirty %cjwait, "
1534					 "not in a newer tranasction",
1535					 (unsigned long long)saved_bh->
1536					 b_blocknr, was_dirty ? ' ' : '!',
1537					 was_jwait ? ' ' : '!');
1538		}
1539		if (was_dirty) {
1540			/* we inc again because saved_bh gets decremented at free_cnode */
1541			get_bh(saved_bh);
1542			set_bit(BLOCK_NEEDS_FLUSH, &cn->state);
1543			lock_buffer(saved_bh);
1544			BUG_ON(cn->blocknr != saved_bh->b_blocknr);
1545			if (buffer_dirty(saved_bh))
1546				submit_logged_buffer(saved_bh);
1547			else
1548				unlock_buffer(saved_bh);
1549			count++;
1550		} else {
1551			reiserfs_warning(s, "clm-2082",
1552					 "Unable to flush buffer %llu in %s",
1553					 (unsigned long long)saved_bh->
1554					 b_blocknr, __func__);
1555		}
1556	      free_cnode:
1557		last = cn;
1558		cn = cn->next;
1559		if (saved_bh) {
1560			/* we incremented this to keep others from taking the buffer head away */
1561			put_bh(saved_bh);
1562			if (atomic_read(&(saved_bh->b_count)) < 0) {
1563				reiserfs_warning(s, "journal-945",
1564						 "saved_bh->b_count < 0");
1565			}
1566		}
1567	}
1568	if (count > 0) {
1569		cn = jl->j_realblock;
1570		while (cn) {
1571			if (test_bit(BLOCK_NEEDS_FLUSH, &cn->state)) {
1572				if (!cn->bh) {
1573					reiserfs_panic(s, "journal-1011",
1574						       "cn->bh is NULL");
1575				}
1576
1577				reiserfs_write_unlock(s);
1578				wait_on_buffer(cn->bh);
1579				reiserfs_write_lock(s);
1580
1581				if (!cn->bh) {
1582					reiserfs_panic(s, "journal-1012",
1583						       "cn->bh is NULL");
1584				}
1585				if (unlikely(!buffer_uptodate(cn->bh))) {
1586#ifdef CONFIG_REISERFS_CHECK
1587					reiserfs_warning(s, "journal-949",
1588							 "buffer write failed");
1589#endif
1590					err = -EIO;
1591				}
1592				/* note, we must clear the JDirty_wait bit after the up to date
1593				 ** check, otherwise we race against our flushpage routine
1594				 */
1595				BUG_ON(!test_clear_buffer_journal_dirty
1596				       (cn->bh));
1597
1598				/* drop one ref for us */
1599				put_bh(cn->bh);
1600				/* drop one ref for journal_mark_dirty */
1601				release_buffer_page(cn->bh);
1602			}
1603			cn = cn->next;
1604		}
1605	}
1606
1607	if (err)
1608		reiserfs_abort(s, -EIO,
1609			       "Write error while pushing transaction to disk in %s",
1610			       __func__);
1611      flush_older_and_return:
1612
1613	/* before we can update the journal header block, we _must_ flush all
1614	 ** real blocks from all older transactions to disk.  This is because
1615	 ** once the header block is updated, this transaction will not be
1616	 ** replayed after a crash
1617	 */
1618	if (flushall) {
1619		flush_older_journal_lists(s, jl);
1620	}
1621
1622	err = journal->j_errno;
1623	/* before we can remove everything from the hash tables for this
1624	 ** transaction, we must make sure it can never be replayed
1625	 **
1626	 ** since we are only called from do_journal_end, we know for sure there
1627	 ** are no allocations going on while we are flushing journal lists.  So,
1628	 ** we only need to update the journal header block for the last list
1629	 ** being flushed
1630	 */
1631	if (!err && flushall) {
1632		err =
1633		    update_journal_header_block(s,
1634						(jl->j_start + jl->j_len +
1635						 2) % SB_ONDISK_JOURNAL_SIZE(s),
1636						jl->j_trans_id);
1637		if (err)
1638			reiserfs_abort(s, -EIO,
1639				       "Write error while updating journal header in %s",
1640				       __func__);
1641	}
1642	remove_all_from_journal_list(s, jl, 0);
1643	list_del_init(&jl->j_list);
1644	journal->j_num_lists--;
1645	del_from_work_list(s, jl);
1646
1647	if (journal->j_last_flush_id != 0 &&
1648	    (jl->j_trans_id - journal->j_last_flush_id) != 1) {
1649		reiserfs_warning(s, "clm-2201", "last flush %lu, current %lu",
1650				 journal->j_last_flush_id, jl->j_trans_id);
1651	}
1652	journal->j_last_flush_id = jl->j_trans_id;
1653
1654	/* not strictly required since we are freeing the list, but it should
1655	 * help find code using dead lists later on
1656	 */
1657	jl->j_len = 0;
1658	atomic_set(&(jl->j_nonzerolen), 0);
1659	jl->j_start = 0;
1660	jl->j_realblock = NULL;
1661	jl->j_commit_bh = NULL;
1662	jl->j_trans_id = 0;
1663	jl->j_state = 0;
1664	put_journal_list(s, jl);
1665	if (flushall)
1666		mutex_unlock(&journal->j_flush_mutex);
1667	put_fs_excl();
1668	return err;
1669}
1670
1671static int test_transaction(struct super_block *s,
1672                            struct reiserfs_journal_list *jl)
1673{
1674	struct reiserfs_journal_cnode *cn;
1675
1676	if (jl->j_len == 0 || atomic_read(&jl->j_nonzerolen) == 0)
1677		return 1;
1678
1679	cn = jl->j_realblock;
1680	while (cn) {
1681		/* if the blocknr == 0, this has been cleared from the hash,
1682		 ** skip it
1683		 */
1684		if (cn->blocknr == 0) {
1685			goto next;
1686		}
1687		if (cn->bh && !newer_jl_done(cn))
1688			return 0;
1689	      next:
1690		cn = cn->next;
1691		cond_resched();
1692	}
1693	return 0;
1694}
1695
1696static int write_one_transaction(struct super_block *s,
1697				 struct reiserfs_journal_list *jl,
1698				 struct buffer_chunk *chunk)
1699{
1700	struct reiserfs_journal_cnode *cn;
1701	int ret = 0;
1702
1703	jl->j_state |= LIST_TOUCHED;
1704	del_from_work_list(s, jl);
1705	if (jl->j_len == 0 || atomic_read(&jl->j_nonzerolen) == 0) {
1706		return 0;
1707	}
1708
1709	cn = jl->j_realblock;
1710	while (cn) {
1711		/* if the blocknr == 0, this has been cleared from the hash,
1712		 ** skip it
1713		 */
1714		if (cn->blocknr == 0) {
1715			goto next;
1716		}
1717		if (cn->bh && can_dirty(cn) && buffer_dirty(cn->bh)) {
1718			struct buffer_head *tmp_bh;
1719			/* we can race against journal_mark_freed when we try
1720			 * to lock_buffer(cn->bh), so we have to inc the buffer
1721			 * count, and recheck things after locking
1722			 */
1723			tmp_bh = cn->bh;
1724			get_bh(tmp_bh);
1725			lock_buffer(tmp_bh);
1726			if (cn->bh && can_dirty(cn) && buffer_dirty(tmp_bh)) {
1727				if (!buffer_journal_dirty(tmp_bh) ||
1728				    buffer_journal_prepared(tmp_bh))
1729					BUG();
1730				add_to_chunk(chunk, tmp_bh, NULL, write_chunk);
1731				ret++;
1732			} else {
1733				/* note, cn->bh might be null now */
1734				unlock_buffer(tmp_bh);
1735			}
1736			put_bh(tmp_bh);
1737		}
1738	      next:
1739		cn = cn->next;
1740		cond_resched();
1741	}
1742	return ret;
1743}
1744
1745/* used by flush_commit_list */
1746static int dirty_one_transaction(struct super_block *s,
1747				 struct reiserfs_journal_list *jl)
1748{
1749	struct reiserfs_journal_cnode *cn;
1750	struct reiserfs_journal_list *pjl;
1751	int ret = 0;
1752
1753	jl->j_state |= LIST_DIRTY;
1754	cn = jl->j_realblock;
1755	while (cn) {
1756		/* look for a more recent transaction that logged this
1757		 ** buffer.  Only the most recent transaction with a buffer in
1758		 ** it is allowed to send that buffer to disk
1759		 */
1760		pjl = find_newer_jl_for_cn(cn);
1761		if (!pjl && cn->blocknr && cn->bh
1762		    && buffer_journal_dirty(cn->bh)) {
1763			BUG_ON(!can_dirty(cn));
1764			/* if the buffer is prepared, it will either be logged
1765			 * or restored.  If restored, we need to make sure
1766			 * it actually gets marked dirty
1767			 */
1768			clear_buffer_journal_new(cn->bh);
1769			if (buffer_journal_prepared(cn->bh)) {
1770				set_buffer_journal_restore_dirty(cn->bh);
1771			} else {
1772				set_buffer_journal_test(cn->bh);
1773				mark_buffer_dirty(cn->bh);
1774			}
1775		}
1776		cn = cn->next;
1777	}
1778	return ret;
1779}
1780
1781static int kupdate_transactions(struct super_block *s,
1782				struct reiserfs_journal_list *jl,
1783				struct reiserfs_journal_list **next_jl,
1784				unsigned int *next_trans_id,
1785				int num_blocks, int num_trans)
1786{
1787	int ret = 0;
1788	int written = 0;
1789	int transactions_flushed = 0;
1790	unsigned int orig_trans_id = jl->j_trans_id;
1791	struct buffer_chunk chunk;
1792	struct list_head *entry;
1793	struct reiserfs_journal *journal = SB_JOURNAL(s);
1794	chunk.nr = 0;
1795
1796	reiserfs_mutex_lock_safe(&journal->j_flush_mutex, s);
1797	if (!journal_list_still_alive(s, orig_trans_id)) {
1798		goto done;
1799	}
1800
1801	/* we've got j_flush_mutex held, nobody is going to delete any
1802	 * of these lists out from underneath us
1803	 */
1804	while ((num_trans && transactions_flushed < num_trans) ||
1805	       (!num_trans && written < num_blocks)) {
1806
1807		if (jl->j_len == 0 || (jl->j_state & LIST_TOUCHED) ||
1808		    atomic_read(&jl->j_commit_left)
1809		    || !(jl->j_state & LIST_DIRTY)) {
1810			del_from_work_list(s, jl);
1811			break;
1812		}
1813		ret = write_one_transaction(s, jl, &chunk);
1814
1815		if (ret < 0)
1816			goto done;
1817		transactions_flushed++;
1818		written += ret;
1819		entry = jl->j_list.next;
1820
1821		/* did we wrap? */
1822		if (entry == &journal->j_journal_list) {
1823			break;
1824		}
1825		jl = JOURNAL_LIST_ENTRY(entry);
1826
1827		/* don't bother with older transactions */
1828		if (jl->j_trans_id <= orig_trans_id)
1829			break;
1830	}
1831	if (chunk.nr) {
1832		write_chunk(&chunk);
1833	}
1834
1835      done:
1836	mutex_unlock(&journal->j_flush_mutex);
1837	return ret;
1838}
1839
1840/* for o_sync and fsync heavy applications, they tend to use
1841** all the journa list slots with tiny transactions.  These
1842** trigger lots and lots of calls to update the header block, which
1843** adds seeks and slows things down.
1844**
1845** This function tries to clear out a large chunk of the journal lists
1846** at once, which makes everything faster since only the newest journal
1847** list updates the header block
1848*/
1849static int flush_used_journal_lists(struct super_block *s,
1850				    struct reiserfs_journal_list *jl)
1851{
1852	unsigned long len = 0;
1853	unsigned long cur_len;
1854	int ret;
1855	int i;
1856	int limit = 256;
1857	struct reiserfs_journal_list *tjl;
1858	struct reiserfs_journal_list *flush_jl;
1859	unsigned int trans_id;
1860	struct reiserfs_journal *journal = SB_JOURNAL(s);
1861
1862	flush_jl = tjl = jl;
1863
1864	/* in data logging mode, try harder to flush a lot of blocks */
1865	if (reiserfs_data_log(s))
1866		limit = 1024;
1867	/* flush for 256 transactions or limit blocks, whichever comes first */
1868	for (i = 0; i < 256 && len < limit; i++) {
1869		if (atomic_read(&tjl->j_commit_left) ||
1870		    tjl->j_trans_id < jl->j_trans_id) {
1871			break;
1872		}
1873		cur_len = atomic_read(&tjl->j_nonzerolen);
1874		if (cur_len > 0) {
1875			tjl->j_state &= ~LIST_TOUCHED;
1876		}
1877		len += cur_len;
1878		flush_jl = tjl;
1879		if (tjl->j_list.next == &journal->j_journal_list)
1880			break;
1881		tjl = JOURNAL_LIST_ENTRY(tjl->j_list.next);
1882	}
1883	/* try to find a group of blocks we can flush across all the
1884	 ** transactions, but only bother if we've actually spanned
1885	 ** across multiple lists
1886	 */
1887	if (flush_jl != jl) {
1888		ret = kupdate_transactions(s, jl, &tjl, &trans_id, len, i);
1889	}
1890	flush_journal_list(s, flush_jl, 1);
1891	return 0;
1892}
1893
1894/*
1895** removes any nodes in table with name block and dev as bh.
1896** only touchs the hnext and hprev pointers.
1897*/
1898void remove_journal_hash(struct super_block *sb,
1899			 struct reiserfs_journal_cnode **table,
1900			 struct reiserfs_journal_list *jl,
1901			 unsigned long block, int remove_freed)
1902{
1903	struct reiserfs_journal_cnode *cur;
1904	struct reiserfs_journal_cnode **head;
1905
1906	head = &(journal_hash(table, sb, block));
1907	if (!head) {
1908		return;
1909	}
1910	cur = *head;
1911	while (cur) {
1912		if (cur->blocknr == block && cur->sb == sb
1913		    && (jl == NULL || jl == cur->jlist)
1914		    && (!test_bit(BLOCK_FREED, &cur->state) || remove_freed)) {
1915			if (cur->hnext) {
1916				cur->hnext->hprev = cur->hprev;
1917			}
1918			if (cur->hprev) {
1919				cur->hprev->hnext = cur->hnext;
1920			} else {
1921				*head = cur->hnext;
1922			}
1923			cur->blocknr = 0;
1924			cur->sb = NULL;
1925			cur->state = 0;
1926			if (cur->bh && cur->jlist)	/* anybody who clears the cur->bh will also dec the nonzerolen */
1927				atomic_dec(&(cur->jlist->j_nonzerolen));
1928			cur->bh = NULL;
1929			cur->jlist = NULL;
1930		}
1931		cur = cur->hnext;
1932	}
1933}
1934
1935static void free_journal_ram(struct super_block *sb)
1936{
1937	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1938	kfree(journal->j_current_jl);
1939	journal->j_num_lists--;
1940
1941	vfree(journal->j_cnode_free_orig);
1942	free_list_bitmaps(sb, journal->j_list_bitmap);
1943	free_bitmap_nodes(sb);	/* must be after free_list_bitmaps */
1944	if (journal->j_header_bh) {
1945		brelse(journal->j_header_bh);
1946	}
1947	/* j_header_bh is on the journal dev, make sure not to release the journal
1948	 * dev until we brelse j_header_bh
1949	 */
1950	release_journal_dev(sb, journal);
1951	vfree(journal);
1952}
1953
1954/*
1955** call on unmount.  Only set error to 1 if you haven't made your way out
1956** of read_super() yet.  Any other caller must keep error at 0.
1957*/
1958static int do_journal_release(struct reiserfs_transaction_handle *th,
1959			      struct super_block *sb, int error)
1960{
1961	struct reiserfs_transaction_handle myth;
1962	int flushed = 0;
1963	struct reiserfs_journal *journal = SB_JOURNAL(sb);
1964
1965	/* we only want to flush out transactions if we were called with error == 0
1966	 */
1967	if (!error && !(sb->s_flags & MS_RDONLY)) {
1968		/* end the current trans */
1969		BUG_ON(!th->t_trans_id);
1970		do_journal_end(th, sb, 10, FLUSH_ALL);
1971
1972		/* make sure something gets logged to force our way into the flush code */
1973		if (!journal_join(&myth, sb, 1)) {
1974			reiserfs_prepare_for_journal(sb,
1975						     SB_BUFFER_WITH_SB(sb),
1976						     1);
1977			journal_mark_dirty(&myth, sb,
1978					   SB_BUFFER_WITH_SB(sb));
1979			do_journal_end(&myth, sb, 1, FLUSH_ALL);
1980			flushed = 1;
1981		}
1982	}
1983
1984	/* this also catches errors during the do_journal_end above */
1985	if (!error && reiserfs_is_journal_aborted(journal)) {
1986		memset(&myth, 0, sizeof(myth));
1987		if (!journal_join_abort(&myth, sb, 1)) {
1988			reiserfs_prepare_for_journal(sb,
1989						     SB_BUFFER_WITH_SB(sb),
1990						     1);
1991			journal_mark_dirty(&myth, sb,
1992					   SB_BUFFER_WITH_SB(sb));
1993			do_journal_end(&myth, sb, 1, FLUSH_ALL);
1994		}
1995	}
1996
1997	reiserfs_mounted_fs_count--;
1998	/* wait for all commits to finish */
1999	cancel_delayed_work(&SB_JOURNAL(sb)->j_work);
2000
2001	/*
2002	 * We must release the write lock here because
2003	 * the workqueue job (flush_async_commit) needs this lock
2004	 */
2005	reiserfs_write_unlock(sb);
2006	flush_workqueue(commit_wq);
2007
2008	if (!reiserfs_mounted_fs_count) {
2009		destroy_workqueue(commit_wq);
2010		commit_wq = NULL;
2011	}
2012
2013	free_journal_ram(sb);
2014
2015	reiserfs_write_lock(sb);
2016
2017	return 0;
2018}
2019
2020/*
2021** call on unmount.  flush all journal trans, release all alloc'd ram
2022*/
2023int journal_release(struct reiserfs_transaction_handle *th,
2024		    struct super_block *sb)
2025{
2026	return do_journal_release(th, sb, 0);
2027}
2028
2029/*
2030** only call from an error condition inside reiserfs_read_super!
2031*/
2032int journal_release_error(struct reiserfs_transaction_handle *th,
2033			  struct super_block *sb)
2034{
2035	return do_journal_release(th, sb, 1);
2036}
2037
2038/* compares description block with commit block.  returns 1 if they differ, 0 if they are the same */
2039static int journal_compare_desc_commit(struct super_block *sb,
2040				       struct reiserfs_journal_desc *desc,
2041				       struct reiserfs_journal_commit *commit)
2042{
2043	if (get_commit_trans_id(commit) != get_desc_trans_id(desc) ||
2044	    get_commit_trans_len(commit) != get_desc_trans_len(desc) ||
2045	    get_commit_trans_len(commit) > SB_JOURNAL(sb)->j_trans_max ||
2046	    get_commit_trans_len(commit) <= 0) {
2047		return 1;
2048	}
2049	return 0;
2050}
2051
2052/* returns 0 if it did not find a description block
2053** returns -1 if it found a corrupt commit block
2054** returns 1 if both desc and commit were valid
2055*/
2056static int journal_transaction_is_valid(struct super_block *sb,
2057					struct buffer_head *d_bh,
2058					unsigned int *oldest_invalid_trans_id,
2059					unsigned long *newest_mount_id)
2060{
2061	struct reiserfs_journal_desc *desc;
2062	struct reiserfs_journal_commit *commit;
2063	struct buffer_head *c_bh;
2064	unsigned long offset;
2065
2066	if (!d_bh)
2067		return 0;
2068
2069	desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2070	if (get_desc_trans_len(desc) > 0
2071	    && !memcmp(get_journal_desc_magic(d_bh), JOURNAL_DESC_MAGIC, 8)) {
2072		if (oldest_invalid_trans_id && *oldest_invalid_trans_id
2073		    && get_desc_trans_id(desc) > *oldest_invalid_trans_id) {
2074			reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2075				       "journal-986: transaction "
2076				       "is valid returning because trans_id %d is greater than "
2077				       "oldest_invalid %lu",
2078				       get_desc_trans_id(desc),
2079				       *oldest_invalid_trans_id);
2080			return 0;
2081		}
2082		if (newest_mount_id
2083		    && *newest_mount_id > get_desc_mount_id(desc)) {
2084			reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2085				       "journal-1087: transaction "
2086				       "is valid returning because mount_id %d is less than "
2087				       "newest_mount_id %lu",
2088				       get_desc_mount_id(desc),
2089				       *newest_mount_id);
2090			return -1;
2091		}
2092		if (get_desc_trans_len(desc) > SB_JOURNAL(sb)->j_trans_max) {
2093			reiserfs_warning(sb, "journal-2018",
2094					 "Bad transaction length %d "
2095					 "encountered, ignoring transaction",
2096					 get_desc_trans_len(desc));
2097			return -1;
2098		}
2099		offset = d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2100
2101		/* ok, we have a journal description block, lets see if the transaction was valid */
2102		c_bh =
2103		    journal_bread(sb,
2104				  SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2105				  ((offset + get_desc_trans_len(desc) +
2106				    1) % SB_ONDISK_JOURNAL_SIZE(sb)));
2107		if (!c_bh)
2108			return 0;
2109		commit = (struct reiserfs_journal_commit *)c_bh->b_data;
2110		if (journal_compare_desc_commit(sb, desc, commit)) {
2111			reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2112				       "journal_transaction_is_valid, commit offset %ld had bad "
2113				       "time %d or length %d",
2114				       c_bh->b_blocknr -
2115				       SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2116				       get_commit_trans_id(commit),
2117				       get_commit_trans_len(commit));
2118			brelse(c_bh);
2119			if (oldest_invalid_trans_id) {
2120				*oldest_invalid_trans_id =
2121				    get_desc_trans_id(desc);
2122				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2123					       "journal-1004: "
2124					       "transaction_is_valid setting oldest invalid trans_id "
2125					       "to %d",
2126					       get_desc_trans_id(desc));
2127			}
2128			return -1;
2129		}
2130		brelse(c_bh);
2131		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2132			       "journal-1006: found valid "
2133			       "transaction start offset %llu, len %d id %d",
2134			       d_bh->b_blocknr -
2135			       SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2136			       get_desc_trans_len(desc),
2137			       get_desc_trans_id(desc));
2138		return 1;
2139	} else {
2140		return 0;
2141	}
2142}
2143
2144static void brelse_array(struct buffer_head **heads, int num)
2145{
2146	int i;
2147	for (i = 0; i < num; i++) {
2148		brelse(heads[i]);
2149	}
2150}
2151
2152/*
2153** given the start, and values for the oldest acceptable transactions,
2154** this either reads in a replays a transaction, or returns because the transaction
2155** is invalid, or too old.
2156*/
2157static int journal_read_transaction(struct super_block *sb,
2158				    unsigned long cur_dblock,
2159				    unsigned long oldest_start,
2160				    unsigned int oldest_trans_id,
2161				    unsigned long newest_mount_id)
2162{
2163	struct reiserfs_journal *journal = SB_JOURNAL(sb);
2164	struct reiserfs_journal_desc *desc;
2165	struct reiserfs_journal_commit *commit;
2166	unsigned int trans_id = 0;
2167	struct buffer_head *c_bh;
2168	struct buffer_head *d_bh;
2169	struct buffer_head **log_blocks = NULL;
2170	struct buffer_head **real_blocks = NULL;
2171	unsigned int trans_offset;
2172	int i;
2173	int trans_half;
2174
2175	d_bh = journal_bread(sb, cur_dblock);
2176	if (!d_bh)
2177		return 1;
2178	desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2179	trans_offset = d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2180	reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1037: "
2181		       "journal_read_transaction, offset %llu, len %d mount_id %d",
2182		       d_bh->b_blocknr - SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2183		       get_desc_trans_len(desc), get_desc_mount_id(desc));
2184	if (get_desc_trans_id(desc) < oldest_trans_id) {
2185		reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1039: "
2186			       "journal_read_trans skipping because %lu is too old",
2187			       cur_dblock -
2188			       SB_ONDISK_JOURNAL_1st_BLOCK(sb));
2189		brelse(d_bh);
2190		return 1;
2191	}
2192	if (get_desc_mount_id(desc) != newest_mount_id) {
2193		reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1146: "
2194			       "journal_read_trans skipping because %d is != "
2195			       "newest_mount_id %lu", get_desc_mount_id(desc),
2196			       newest_mount_id);
2197		brelse(d_bh);
2198		return 1;
2199	}
2200	c_bh = journal_bread(sb, SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2201			     ((trans_offset + get_desc_trans_len(desc) + 1) %
2202			      SB_ONDISK_JOURNAL_SIZE(sb)));
2203	if (!c_bh) {
2204		brelse(d_bh);
2205		return 1;
2206	}
2207	commit = (struct reiserfs_journal_commit *)c_bh->b_data;
2208	if (journal_compare_desc_commit(sb, desc, commit)) {
2209		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2210			       "journal_read_transaction, "
2211			       "commit offset %llu had bad time %d or length %d",
2212			       c_bh->b_blocknr -
2213			       SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2214			       get_commit_trans_id(commit),
2215			       get_commit_trans_len(commit));
2216		brelse(c_bh);
2217		brelse(d_bh);
2218		return 1;
2219	}
2220
2221	if (bdev_read_only(sb->s_bdev)) {
2222		reiserfs_warning(sb, "clm-2076",
2223				 "device is readonly, unable to replay log");
2224		brelse(c_bh);
2225		brelse(d_bh);
2226		return -EROFS;
2227	}
2228
2229	trans_id = get_desc_trans_id(desc);
2230	/* now we know we've got a good transaction, and it was inside the valid time ranges */
2231	log_blocks = kmalloc(get_desc_trans_len(desc) *
2232			     sizeof(struct buffer_head *), GFP_NOFS);
2233	real_blocks = kmalloc(get_desc_trans_len(desc) *
2234			      sizeof(struct buffer_head *), GFP_NOFS);
2235	if (!log_blocks || !real_blocks) {
2236		brelse(c_bh);
2237		brelse(d_bh);
2238		kfree(log_blocks);
2239		kfree(real_blocks);
2240		reiserfs_warning(sb, "journal-1169",
2241				 "kmalloc failed, unable to mount FS");
2242		return -1;
2243	}
2244	/* get all the buffer heads */
2245	trans_half = journal_trans_half(sb->s_blocksize);
2246	for (i = 0; i < get_desc_trans_len(desc); i++) {
2247		log_blocks[i] =
2248		    journal_getblk(sb,
2249				   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2250				   (trans_offset + 1 +
2251				    i) % SB_ONDISK_JOURNAL_SIZE(sb));
2252		if (i < trans_half) {
2253			real_blocks[i] =
2254			    sb_getblk(sb,
2255				      le32_to_cpu(desc->j_realblock[i]));
2256		} else {
2257			real_blocks[i] =
2258			    sb_getblk(sb,
2259				      le32_to_cpu(commit->
2260						  j_realblock[i - trans_half]));
2261		}
2262		if (real_blocks[i]->b_blocknr > SB_BLOCK_COUNT(sb)) {
2263			reiserfs_warning(sb, "journal-1207",
2264					 "REPLAY FAILURE fsck required! "
2265					 "Block to replay is outside of "
2266					 "filesystem");
2267			goto abort_replay;
2268		}
2269		/* make sure we don't try to replay onto log or reserved area */
2270		if (is_block_in_log_or_reserved_area
2271		    (sb, real_blocks[i]->b_blocknr)) {
2272			reiserfs_warning(sb, "journal-1204",
2273					 "REPLAY FAILURE fsck required! "
2274					 "Trying to replay onto a log block");
2275		      abort_replay:
2276			brelse_array(log_blocks, i);
2277			brelse_array(real_blocks, i);
2278			brelse(c_bh);
2279			brelse(d_bh);
2280			kfree(log_blocks);
2281			kfree(real_blocks);
2282			return -1;
2283		}
2284	}
2285	/* read in the log blocks, memcpy to the corresponding real block */
2286	ll_rw_block(READ, get_desc_trans_len(desc), log_blocks);
2287	for (i = 0; i < get_desc_trans_len(desc); i++) {
2288
2289		reiserfs_write_unlock(sb);
2290		wait_on_buffer(log_blocks[i]);
2291		reiserfs_write_lock(sb);
2292
2293		if (!buffer_uptodate(log_blocks[i])) {
2294			reiserfs_warning(sb, "journal-1212",
2295					 "REPLAY FAILURE fsck required! "
2296					 "buffer write failed");
2297			brelse_array(log_blocks + i,
2298				     get_desc_trans_len(desc) - i);
2299			brelse_array(real_blocks, get_desc_trans_len(desc));
2300			brelse(c_bh);
2301			brelse(d_bh);
2302			kfree(log_blocks);
2303			kfree(real_blocks);
2304			return -1;
2305		}
2306		memcpy(real_blocks[i]->b_data, log_blocks[i]->b_data,
2307		       real_blocks[i]->b_size);
2308		set_buffer_uptodate(real_blocks[i]);
2309		brelse(log_blocks[i]);
2310	}
2311	/* flush out the real blocks */
2312	for (i = 0; i < get_desc_trans_len(desc); i++) {
2313		set_buffer_dirty(real_blocks[i]);
2314		write_dirty_buffer(real_blocks[i], WRITE);
2315	}
2316	for (i = 0; i < get_desc_trans_len(desc); i++) {
2317		wait_on_buffer(real_blocks[i]);
2318		if (!buffer_uptodate(real_blocks[i])) {
2319			reiserfs_warning(sb, "journal-1226",
2320					 "REPLAY FAILURE, fsck required! "
2321					 "buffer write failed");
2322			brelse_array(real_blocks + i,
2323				     get_desc_trans_len(desc) - i);
2324			brelse(c_bh);
2325			brelse(d_bh);
2326			kfree(log_blocks);
2327			kfree(real_blocks);
2328			return -1;
2329		}
2330		brelse(real_blocks[i]);
2331	}
2332	cur_dblock =
2333	    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2334	    ((trans_offset + get_desc_trans_len(desc) +
2335	      2) % SB_ONDISK_JOURNAL_SIZE(sb));
2336	reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2337		       "journal-1095: setting journal " "start to offset %ld",
2338		       cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb));
2339
2340	/* init starting values for the first transaction, in case this is the last transaction to be replayed. */
2341	journal->j_start = cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2342	journal->j_last_flush_trans_id = trans_id;
2343	journal->j_trans_id = trans_id + 1;
2344	/* check for trans_id overflow */
2345	if (journal->j_trans_id == 0)
2346		journal->j_trans_id = 10;
2347	brelse(c_bh);
2348	brelse(d_bh);
2349	kfree(log_blocks);
2350	kfree(real_blocks);
2351	return 0;
2352}
2353
2354/* This function reads blocks starting from block and to max_block of bufsize
2355   size (but no more than BUFNR blocks at a time). This proved to improve
2356   mounting speed on self-rebuilding raid5 arrays at least.
2357   Right now it is only used from journal code. But later we might use it
2358   from other places.
2359   Note: Do not use journal_getblk/sb_getblk functions here! */
2360static struct buffer_head *reiserfs_breada(struct block_device *dev,
2361					   b_blocknr_t block, int bufsize,
2362					   b_blocknr_t max_block)
2363{
2364	struct buffer_head *bhlist[BUFNR];
2365	unsigned int blocks = BUFNR;
2366	struct buffer_head *bh;
2367	int i, j;
2368
2369	bh = __getblk(dev, block, bufsize);
2370	if (buffer_uptodate(bh))
2371		return (bh);
2372
2373	if (block + BUFNR > max_block) {
2374		blocks = max_block - block;
2375	}
2376	bhlist[0] = bh;
2377	j = 1;
2378	for (i = 1; i < blocks; i++) {
2379		bh = __getblk(dev, block + i, bufsize);
2380		if (buffer_uptodate(bh)) {
2381			brelse(bh);
2382			break;
2383		} else
2384			bhlist[j++] = bh;
2385	}
2386	ll_rw_block(READ, j, bhlist);
2387	for (i = 1; i < j; i++)
2388		brelse(bhlist[i]);
2389	bh = bhlist[0];
2390	wait_on_buffer(bh);
2391	if (buffer_uptodate(bh))
2392		return bh;
2393	brelse(bh);
2394	return NULL;
2395}
2396
2397/*
2398** read and replay the log
2399** on a clean unmount, the journal header's next unflushed pointer will be to an invalid
2400** transaction.  This tests that before finding all the transactions in the log, which makes normal mount times fast.
2401**
2402** After a crash, this starts with the next unflushed transaction, and replays until it finds one too old, or invalid.
2403**
2404** On exit, it sets things up so the first transaction will work correctly.
2405*/
2406static int journal_read(struct super_block *sb)
2407{
2408	struct reiserfs_journal *journal = SB_JOURNAL(sb);
2409	struct reiserfs_journal_desc *desc;
2410	unsigned int oldest_trans_id = 0;
2411	unsigned int oldest_invalid_trans_id = 0;
2412	time_t start;
2413	unsigned long oldest_start = 0;
2414	unsigned long cur_dblock = 0;
2415	unsigned long newest_mount_id = 9;
2416	struct buffer_head *d_bh;
2417	struct reiserfs_journal_header *jh;
2418	int valid_journal_header = 0;
2419	int replay_count = 0;
2420	int continue_replay = 1;
2421	int ret;
2422	char b[BDEVNAME_SIZE];
2423
2424	cur_dblock = SB_ONDISK_JOURNAL_1st_BLOCK(sb);
2425	reiserfs_info(sb, "checking transaction log (%s)\n",
2426		      bdevname(journal->j_dev_bd, b));
2427	start = get_seconds();
2428
2429	/* step 1, read in the journal header block.  Check the transaction it says
2430	 ** is the first unflushed, and if that transaction is not valid,
2431	 ** replay is done
2432	 */
2433	journal->j_header_bh = journal_bread(sb,
2434					     SB_ONDISK_JOURNAL_1st_BLOCK(sb)
2435					     + SB_ONDISK_JOURNAL_SIZE(sb));
2436	if (!journal->j_header_bh) {
2437		return 1;
2438	}
2439	jh = (struct reiserfs_journal_header *)(journal->j_header_bh->b_data);
2440	if (le32_to_cpu(jh->j_first_unflushed_offset) <
2441	    SB_ONDISK_JOURNAL_SIZE(sb)
2442	    && le32_to_cpu(jh->j_last_flush_trans_id) > 0) {
2443		oldest_start =
2444		    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2445		    le32_to_cpu(jh->j_first_unflushed_offset);
2446		oldest_trans_id = le32_to_cpu(jh->j_last_flush_trans_id) + 1;
2447		newest_mount_id = le32_to_cpu(jh->j_mount_id);
2448		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2449			       "journal-1153: found in "
2450			       "header: first_unflushed_offset %d, last_flushed_trans_id "
2451			       "%lu", le32_to_cpu(jh->j_first_unflushed_offset),
2452			       le32_to_cpu(jh->j_last_flush_trans_id));
2453		valid_journal_header = 1;
2454
2455		/* now, we try to read the first unflushed offset.  If it is not valid,
2456		 ** there is nothing more we can do, and it makes no sense to read
2457		 ** through the whole log.
2458		 */
2459		d_bh =
2460		    journal_bread(sb,
2461				  SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2462				  le32_to_cpu(jh->j_first_unflushed_offset));
2463		ret = journal_transaction_is_valid(sb, d_bh, NULL, NULL);
2464		if (!ret) {
2465			continue_replay = 0;
2466		}
2467		brelse(d_bh);
2468		goto start_log_replay;
2469	}
2470
2471	/* ok, there are transactions that need to be replayed.  start with the first log block, find
2472	 ** all the valid transactions, and pick out the oldest.
2473	 */
2474	while (continue_replay
2475	       && cur_dblock <
2476	       (SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2477		SB_ONDISK_JOURNAL_SIZE(sb))) {
2478		/* Note that it is required for blocksize of primary fs device and journal
2479		   device to be the same */
2480		d_bh =
2481		    reiserfs_breada(journal->j_dev_bd, cur_dblock,
2482				    sb->s_blocksize,
2483				    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2484				    SB_ONDISK_JOURNAL_SIZE(sb));
2485		ret =
2486		    journal_transaction_is_valid(sb, d_bh,
2487						 &oldest_invalid_trans_id,
2488						 &newest_mount_id);
2489		if (ret == 1) {
2490			desc = (struct reiserfs_journal_desc *)d_bh->b_data;
2491			if (oldest_start == 0) {	/* init all oldest_ values */
2492				oldest_trans_id = get_desc_trans_id(desc);
2493				oldest_start = d_bh->b_blocknr;
2494				newest_mount_id = get_desc_mount_id(desc);
2495				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2496					       "journal-1179: Setting "
2497					       "oldest_start to offset %llu, trans_id %lu",
2498					       oldest_start -
2499					       SB_ONDISK_JOURNAL_1st_BLOCK
2500					       (sb), oldest_trans_id);
2501			} else if (oldest_trans_id > get_desc_trans_id(desc)) {
2502				/* one we just read was older */
2503				oldest_trans_id = get_desc_trans_id(desc);
2504				oldest_start = d_bh->b_blocknr;
2505				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2506					       "journal-1180: Resetting "
2507					       "oldest_start to offset %lu, trans_id %lu",
2508					       oldest_start -
2509					       SB_ONDISK_JOURNAL_1st_BLOCK
2510					       (sb), oldest_trans_id);
2511			}
2512			if (newest_mount_id < get_desc_mount_id(desc)) {
2513				newest_mount_id = get_desc_mount_id(desc);
2514				reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2515					       "journal-1299: Setting "
2516					       "newest_mount_id to %d",
2517					       get_desc_mount_id(desc));
2518			}
2519			cur_dblock += get_desc_trans_len(desc) + 2;
2520		} else {
2521			cur_dblock++;
2522		}
2523		brelse(d_bh);
2524	}
2525
2526      start_log_replay:
2527	cur_dblock = oldest_start;
2528	if (oldest_trans_id) {
2529		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2530			       "journal-1206: Starting replay "
2531			       "from offset %llu, trans_id %lu",
2532			       cur_dblock - SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2533			       oldest_trans_id);
2534
2535	}
2536	replay_count = 0;
2537	while (continue_replay && oldest_trans_id > 0) {
2538		ret =
2539		    journal_read_transaction(sb, cur_dblock, oldest_start,
2540					     oldest_trans_id, newest_mount_id);
2541		if (ret < 0) {
2542			return ret;
2543		} else if (ret != 0) {
2544			break;
2545		}
2546		cur_dblock =
2547		    SB_ONDISK_JOURNAL_1st_BLOCK(sb) + journal->j_start;
2548		replay_count++;
2549		if (cur_dblock == oldest_start)
2550			break;
2551	}
2552
2553	if (oldest_trans_id == 0) {
2554		reiserfs_debug(sb, REISERFS_DEBUG_CODE,
2555			       "journal-1225: No valid " "transactions found");
2556	}
2557	/* j_start does not get set correctly if we don't replay any transactions.
2558	 ** if we had a valid journal_header, set j_start to the first unflushed transaction value,
2559	 ** copy the trans_id from the header
2560	 */
2561	if (valid_journal_header && replay_count == 0) {
2562		journal->j_start = le32_to_cpu(jh->j_first_unflushed_offset);
2563		journal->j_trans_id =
2564		    le32_to_cpu(jh->j_last_flush_trans_id) + 1;
2565		/* check for trans_id overflow */
2566		if (journal->j_trans_id == 0)
2567			journal->j_trans_id = 10;
2568		journal->j_last_flush_trans_id =
2569		    le32_to_cpu(jh->j_last_flush_trans_id);
2570		journal->j_mount_id = le32_to_cpu(jh->j_mount_id) + 1;
2571	} else {
2572		journal->j_mount_id = newest_mount_id + 1;
2573	}
2574	reiserfs_debug(sb, REISERFS_DEBUG_CODE, "journal-1299: Setting "
2575		       "newest_mount_id to %lu", journal->j_mount_id);
2576	journal->j_first_unflushed_offset = journal->j_start;
2577	if (replay_count > 0) {
2578		reiserfs_info(sb,
2579			      "replayed %d transactions in %lu seconds\n",
2580			      replay_count, get_seconds() - start);
2581	}
2582	if (!bdev_read_only(sb->s_bdev) &&
2583	    _update_journal_header_block(sb, journal->j_start,
2584					 journal->j_last_flush_trans_id)) {
2585		/* replay failed, caller must call free_journal_ram and abort
2586		 ** the mount
2587		 */
2588		return -1;
2589	}
2590	return 0;
2591}
2592
2593static struct reiserfs_journal_list *alloc_journal_list(struct super_block *s)
2594{
2595	struct reiserfs_journal_list *jl;
2596	jl = kzalloc(sizeof(struct reiserfs_journal_list),
2597		     GFP_NOFS | __GFP_NOFAIL);
2598	INIT_LIST_HEAD(&jl->j_list);
2599	INIT_LIST_HEAD(&jl->j_working_list);
2600	INIT_LIST_HEAD(&jl->j_tail_bh_list);
2601	INIT_LIST_HEAD(&jl->j_bh_list);
2602	mutex_init(&jl->j_commit_mutex);
2603	SB_JOURNAL(s)->j_num_lists++;
2604	get_journal_list(jl);
2605	return jl;
2606}
2607
2608static void journal_list_init(struct super_block *sb)
2609{
2610	SB_JOURNAL(sb)->j_current_jl = alloc_journal_list(sb);
2611}
2612
2613static int release_journal_dev(struct super_block *super,
2614			       struct reiserfs_journal *journal)
2615{
2616	int result;
2617
2618	result = 0;
2619
2620	if (journal->j_dev_bd != NULL) {
2621		if (journal->j_dev_bd->bd_dev != super->s_dev)
2622			bd_release(journal->j_dev_bd);
2623		result = blkdev_put(journal->j_dev_bd, journal->j_dev_mode);
2624		journal->j_dev_bd = NULL;
2625	}
2626
2627	if (result != 0) {
2628		reiserfs_warning(super, "sh-457",
2629				 "Cannot release journal device: %i", result);
2630	}
2631	return result;
2632}
2633
2634static int journal_init_dev(struct super_block *super,
2635			    struct reiserfs_journal *journal,
2636			    const char *jdev_name)
2637{
2638	int result;
2639	dev_t jdev;
2640	fmode_t blkdev_mode = FMODE_READ | FMODE_WRITE;
2641	char b[BDEVNAME_SIZE];
2642
2643	result = 0;
2644
2645	journal->j_dev_bd = NULL;
2646	jdev = SB_ONDISK_JOURNAL_DEVICE(super) ?
2647	    new_decode_dev(SB_ONDISK_JOURNAL_DEVICE(super)) : super->s_dev;
2648
2649	if (bdev_read_only(super->s_bdev))
2650		blkdev_mode = FMODE_READ;
2651
2652	/* there is no "jdev" option and journal is on separate device */
2653	if ((!jdev_name || !jdev_name[0])) {
2654		journal->j_dev_bd = open_by_devnum(jdev, blkdev_mode);
2655		journal->j_dev_mode = blkdev_mode;
2656		if (IS_ERR(journal->j_dev_bd)) {
2657			result = PTR_ERR(journal->j_dev_bd);
2658			journal->j_dev_bd = NULL;
2659			reiserfs_warning(super, "sh-458",
2660					 "cannot init journal device '%s': %i",
2661					 __bdevname(jdev, b), result);
2662			return result;
2663		} else if (jdev != super->s_dev) {
2664			result = bd_claim(journal->j_dev_bd, journal);
2665			if (result) {
2666				blkdev_put(journal->j_dev_bd, blkdev_mode);
2667				return result;
2668			}
2669
2670			set_blocksize(journal->j_dev_bd, super->s_blocksize);
2671		}
2672
2673		return 0;
2674	}
2675
2676	journal->j_dev_mode = blkdev_mode;
2677	journal->j_dev_bd = open_bdev_exclusive(jdev_name,
2678						blkdev_mode, journal);
2679	if (IS_ERR(journal->j_dev_bd)) {
2680		result = PTR_ERR(journal->j_dev_bd);
2681		journal->j_dev_bd = NULL;
2682		reiserfs_warning(super,
2683				 "journal_init_dev: Cannot open '%s': %i",
2684				 jdev_name, result);
2685		return result;
2686	}
2687
2688	set_blocksize(journal->j_dev_bd, super->s_blocksize);
2689	reiserfs_info(super,
2690		      "journal_init_dev: journal device: %s\n",
2691		      bdevname(journal->j_dev_bd, b));
2692	return 0;
2693}
2694
2695/**
2696 * When creating/tuning a file system user can assign some
2697 * journal params within boundaries which depend on the ratio
2698 * blocksize/standard_blocksize.
2699 *
2700 * For blocks >= standard_blocksize transaction size should
2701 * be not less then JOURNAL_TRANS_MIN_DEFAULT, and not more
2702 * then JOURNAL_TRANS_MAX_DEFAULT.
2703 *
2704 * For blocks < standard_blocksize these boundaries should be
2705 * decreased proportionally.
2706 */
2707#define REISERFS_STANDARD_BLKSIZE (4096)
2708
2709static int check_advise_trans_params(struct super_block *sb,
2710				     struct reiserfs_journal *journal)
2711{
2712        if (journal->j_trans_max) {
2713	        /* Non-default journal params.
2714		   Do sanity check for them. */
2715	        int ratio = 1;
2716		if (sb->s_blocksize < REISERFS_STANDARD_BLKSIZE)
2717		        ratio = REISERFS_STANDARD_BLKSIZE / sb->s_blocksize;
2718
2719		if (journal->j_trans_max > JOURNAL_TRANS_MAX_DEFAULT / ratio ||
2720		    journal->j_trans_max < JOURNAL_TRANS_MIN_DEFAULT / ratio ||
2721		    SB_ONDISK_JOURNAL_SIZE(sb) / journal->j_trans_max <
2722		    JOURNAL_MIN_RATIO) {
2723			reiserfs_warning(sb, "sh-462",
2724					 "bad transaction max size (%u). "
2725					 "FSCK?", journal->j_trans_max);
2726			return 1;
2727		}
2728		if (journal->j_max_batch != (journal->j_trans_max) *
2729		        JOURNAL_MAX_BATCH_DEFAULT/JOURNAL_TRANS_MAX_DEFAULT) {
2730			reiserfs_warning(sb, "sh-463",
2731					 "bad transaction max batch (%u). "
2732					 "FSCK?", journal->j_max_batch);
2733			return 1;
2734		}
2735	} else {
2736		/* Default journal params.
2737                   The file system was created by old version
2738		   of mkreiserfs, so some fields contain zeros,
2739		   and we need to advise proper values for them */
2740		if (sb->s_blocksize != REISERFS_STANDARD_BLKSIZE) {
2741			reiserfs_warning(sb, "sh-464", "bad blocksize (%u)",
2742					 sb->s_blocksize);
2743			return 1;
2744		}
2745		journal->j_trans_max = JOURNAL_TRANS_MAX_DEFAULT;
2746		journal->j_max_batch = JOURNAL_MAX_BATCH_DEFAULT;
2747		journal->j_max_commit_age = JOURNAL_MAX_COMMIT_AGE;
2748	}
2749	return 0;
2750}
2751
2752/*
2753** must be called once on fs mount.  calls journal_read for you
2754*/
2755int journal_init(struct super_block *sb, const char *j_dev_name,
2756		 int old_format, unsigned int commit_max_age)
2757{
2758	int num_cnodes = SB_ONDISK_JOURNAL_SIZE(sb) * 2;
2759	struct buffer_head *bhjh;
2760	struct reiserfs_super_block *rs;
2761	struct reiserfs_journal_header *jh;
2762	struct reiserfs_journal *journal;
2763	struct reiserfs_journal_list *jl;
2764	char b[BDEVNAME_SIZE];
2765	int ret;
2766
2767	/*
2768	 * Unlock here to avoid various RECLAIM-FS-ON <-> IN-RECLAIM-FS
2769	 * dependency inversion warnings.
2770	 */
2771	reiserfs_write_unlock(sb);
2772	journal = SB_JOURNAL(sb) = vmalloc(sizeof(struct reiserfs_journal));
2773	if (!journal) {
2774		reiserfs_warning(sb, "journal-1256",
2775				 "unable to get memory for journal structure");
2776		reiserfs_write_lock(sb);
2777		return 1;
2778	}
2779	memset(journal, 0, sizeof(struct reiserfs_journal));
2780	INIT_LIST_HEAD(&journal->j_bitmap_nodes);
2781	INIT_LIST_HEAD(&journal->j_prealloc_list);
2782	INIT_LIST_HEAD(&journal->j_working_list);
2783	INIT_LIST_HEAD(&journal->j_journal_list);
2784	journal->j_persistent_trans = 0;
2785	ret = reiserfs_allocate_list_bitmaps(sb, journal->j_list_bitmap,
2786					   reiserfs_bmap_count(sb));
2787	reiserfs_write_lock(sb);
2788	if (ret)
2789		goto free_and_return;
2790
2791	allocate_bitmap_nodes(sb);
2792
2793	/* reserved for journal area support */
2794	SB_JOURNAL_1st_RESERVED_BLOCK(sb) = (old_format ?
2795						 REISERFS_OLD_DISK_OFFSET_IN_BYTES
2796						 / sb->s_blocksize +
2797						 reiserfs_bmap_count(sb) +
2798						 1 :
2799						 REISERFS_DISK_OFFSET_IN_BYTES /
2800						 sb->s_blocksize + 2);
2801
2802	/* Sanity check to see is the standard journal fitting withing first bitmap
2803	   (actual for small blocksizes) */
2804	if (!SB_ONDISK_JOURNAL_DEVICE(sb) &&
2805	    (SB_JOURNAL_1st_RESERVED_BLOCK(sb) +
2806	     SB_ONDISK_JOURNAL_SIZE(sb) > sb->s_blocksize * 8)) {
2807		reiserfs_warning(sb, "journal-1393",
2808				 "journal does not fit for area addressed "
2809				 "by first of bitmap blocks. It starts at "
2810				 "%u and its size is %u. Block size %ld",
2811				 SB_JOURNAL_1st_RESERVED_BLOCK(sb),
2812				 SB_ONDISK_JOURNAL_SIZE(sb),
2813				 sb->s_blocksize);
2814		goto free_and_return;
2815	}
2816
2817	/*
2818	 * We need to unlock here to avoid creating the following
2819	 * dependency:
2820	 * reiserfs_lock -> sysfs_mutex
2821	 * Because the reiserfs mmap path creates the following dependency:
2822	 * mm->mmap -> reiserfs_lock, hence we have
2823	 * mm->mmap -> reiserfs_lock ->sysfs_mutex
2824	 * This would ends up in a circular dependency with sysfs readdir path
2825	 * which does sysfs_mutex -> mm->mmap_sem
2826	 * This is fine because the reiserfs lock is useless in mount path,
2827	 * at least until we call journal_begin. We keep it for paranoid
2828	 * reasons.
2829	 */
2830	reiserfs_write_unlock(sb);
2831	if (journal_init_dev(sb, journal, j_dev_name) != 0) {
2832		reiserfs_write_lock(sb);
2833		reiserfs_warning(sb, "sh-462",
2834				 "unable to initialize jornal device");
2835		goto free_and_return;
2836	}
2837	reiserfs_write_lock(sb);
2838
2839	rs = SB_DISK_SUPER_BLOCK(sb);
2840
2841	/* read journal header */
2842	bhjh = journal_bread(sb,
2843			     SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
2844			     SB_ONDISK_JOURNAL_SIZE(sb));
2845	if (!bhjh) {
2846		reiserfs_warning(sb, "sh-459",
2847				 "unable to read journal header");
2848		goto free_and_return;
2849	}
2850	jh = (struct reiserfs_journal_header *)(bhjh->b_data);
2851
2852	/* make sure that journal matches to the super block */
2853	if (is_reiserfs_jr(rs)
2854	    && (le32_to_cpu(jh->jh_journal.jp_journal_magic) !=
2855		sb_jp_journal_magic(rs))) {
2856		reiserfs_warning(sb, "sh-460",
2857				 "journal header magic %x (device %s) does "
2858				 "not match to magic found in super block %x",
2859				 jh->jh_journal.jp_journal_magic,
2860				 bdevname(journal->j_dev_bd, b),
2861				 sb_jp_journal_magic(rs));
2862		brelse(bhjh);
2863		goto free_and_return;
2864	}
2865
2866	journal->j_trans_max = le32_to_cpu(jh->jh_journal.jp_journal_trans_max);
2867	journal->j_max_batch = le32_to_cpu(jh->jh_journal.jp_journal_max_batch);
2868	journal->j_max_commit_age =
2869	    le32_to_cpu(jh->jh_journal.jp_journal_max_commit_age);
2870	journal->j_max_trans_age = JOURNAL_MAX_TRANS_AGE;
2871
2872	if (check_advise_trans_params(sb, journal) != 0)
2873	        goto free_and_return;
2874	journal->j_default_max_commit_age = journal->j_max_commit_age;
2875
2876	if (commit_max_age != 0) {
2877		journal->j_max_commit_age = commit_max_age;
2878		journal->j_max_trans_age = commit_max_age;
2879	}
2880
2881	reiserfs_info(sb, "journal params: device %s, size %u, "
2882		      "journal first block %u, max trans len %u, max batch %u, "
2883		      "max commit age %u, max trans age %u\n",
2884		      bdevname(journal->j_dev_bd, b),
2885		      SB_ONDISK_JOURNAL_SIZE(sb),
2886		      SB_ONDISK_JOURNAL_1st_BLOCK(sb),
2887		      journal->j_trans_max,
2888		      journal->j_max_batch,
2889		      journal->j_max_commit_age, journal->j_max_trans_age);
2890
2891	brelse(bhjh);
2892
2893	journal->j_list_bitmap_index = 0;
2894	journal_list_init(sb);
2895
2896	memset(journal->j_list_hash_table, 0,
2897	       JOURNAL_HASH_SIZE * sizeof(struct reiserfs_journal_cnode *));
2898
2899	INIT_LIST_HEAD(&journal->j_dirty_buffers);
2900	spin_lock_init(&journal->j_dirty_buffers_lock);
2901
2902	journal->j_start = 0;
2903	journal->j_len = 0;
2904	journal->j_len_alloc = 0;
2905	atomic_set(&(journal->j_wcount), 0);
2906	atomic_set(&(journal->j_async_throttle), 0);
2907	journal->j_bcount = 0;
2908	journal->j_trans_start_time = 0;
2909	journal->j_last = NULL;
2910	journal->j_first = NULL;
2911	init_waitqueue_head(&(journal->j_join_wait));
2912	mutex_init(&journal->j_mutex);
2913	mutex_init(&journal->j_flush_mutex);
2914
2915	journal->j_trans_id = 10;
2916	journal->j_mount_id = 10;
2917	journal->j_state = 0;
2918	atomic_set(&(journal->j_jlock), 0);
2919	reiserfs_write_unlock(sb);
2920	journal->j_cnode_free_list = allocate_cnodes(num_cnodes);
2921	reiserfs_write_lock(sb);
2922	journal->j_cnode_free_orig = journal->j_cnode_free_list;
2923	journal->j_cnode_free = journal->j_cnode_free_list ? num_cnodes : 0;
2924	journal->j_cnode_used = 0;
2925	journal->j_must_wait = 0;
2926
2927	if (journal->j_cnode_free == 0) {
2928		reiserfs_warning(sb, "journal-2004", "Journal cnode memory "
2929		                 "allocation failed (%ld bytes). Journal is "
2930		                 "too large for available memory. Usually "
2931		                 "this is due to a journal that is too large.",
2932		                 sizeof (struct reiserfs_journal_cnode) * num_cnodes);
2933        	goto free_and_return;
2934	}
2935
2936	init_journal_hash(sb);
2937	jl = journal->j_current_jl;
2938	jl->j_list_bitmap = get_list_bitmap(sb, jl);
2939	if (!jl->j_list_bitmap) {
2940		reiserfs_warning(sb, "journal-2005",
2941				 "get_list_bitmap failed for journal list 0");
2942		goto free_and_return;
2943	}
2944	if (journal_read(sb) < 0) {
2945		reiserfs_warning(sb, "reiserfs-2006",
2946				 "Replay Failure, unable to mount");
2947		goto free_and_return;
2948	}
2949
2950	reiserfs_mounted_fs_count++;
2951	if (reiserfs_mounted_fs_count <= 1) {
2952		reiserfs_write_unlock(sb);
2953		commit_wq = create_workqueue("reiserfs");
2954		reiserfs_write_lock(sb);
2955	}
2956
2957	INIT_DELAYED_WORK(&journal->j_work, flush_async_commits);
2958	journal->j_work_sb = sb;
2959	return 0;
2960      free_and_return:
2961	free_journal_ram(sb);
2962	return 1;
2963}
2964
2965/*
2966** test for a polite end of the current transaction.  Used by file_write, and should
2967** be used by delete to make sure they don't write more than can fit inside a single
2968** transaction
2969*/
2970int journal_transaction_should_end(struct reiserfs_transaction_handle *th,
2971				   int new_alloc)
2972{
2973	struct reiserfs_journal *journal = SB_JOURNAL(th->t_super);
2974	time_t now = get_seconds();
2975	/* cannot restart while nested */
2976	BUG_ON(!th->t_trans_id);
2977	if (th->t_refcount > 1)
2978		return 0;
2979	if (journal->j_must_wait > 0 ||
2980	    (journal->j_len_alloc + new_alloc) >= journal->j_max_batch ||
2981	    atomic_read(&(journal->j_jlock)) ||
2982	    (now - journal->j_trans_start_time) > journal->j_max_trans_age ||
2983	    journal->j_cnode_free < (journal->j_trans_max * 3)) {
2984		return 1;
2985	}
2986	/* protected by the BKL here */
2987	journal->j_len_alloc += new_alloc;
2988	th->t_blocks_allocated += new_alloc ;
2989	return 0;
2990}
2991
2992/* this must be called inside a transaction, and requires the
2993** kernel_lock to be held
2994*/
2995void reiserfs_block_writes(struct reiserfs_transaction_handle *th)
2996{
2997	struct reiserfs_journal *journal = SB_JOURNAL(th->t_super);
2998	BUG_ON(!th->t_trans_id);
2999	journal->j_must_wait = 1;
3000	set_bit(J_WRITERS_BLOCKED, &journal->j_state);
3001	return;
3002}
3003
3004/* this must be called without a transaction started, and does not
3005** require BKL
3006*/
3007void reiserfs_allow_writes(struct super_block *s)
3008{
3009	struct reiserfs_journal *journal = SB_JOURNAL(s);
3010	clear_bit(J_WRITERS_BLOCKED, &journal->j_state);
3011	wake_up(&journal->j_join_wait);
3012}
3013
3014/* this must be called without a transaction started, and does not
3015** require BKL
3016*/
3017void reiserfs_wait_on_write_block(struct super_block *s)
3018{
3019	struct reiserfs_journal *journal = SB_JOURNAL(s);
3020	wait_event(journal->j_join_wait,
3021		   !test_bit(J_WRITERS_BLOCKED, &journal->j_state));
3022}
3023
3024static void queue_log_writer(struct super_block *s)
3025{
3026	wait_queue_t wait;
3027	struct reiserfs_journal *journal = SB_JOURNAL(s);
3028	set_bit(J_WRITERS_QUEUED, &journal->j_state);
3029
3030	/*
3031	 * we don't want to use wait_event here because
3032	 * we only want to wait once.
3033	 */
3034	init_waitqueue_entry(&wait, current);
3035	add_wait_queue(&journal->j_join_wait, &wait);
3036	set_current_state(TASK_UNINTERRUPTIBLE);
3037	if (test_bit(J_WRITERS_QUEUED, &journal->j_state)) {
3038		reiserfs_write_unlock(s);
3039		schedule();
3040		reiserfs_write_lock(s);
3041	}
3042	__set_current_state(TASK_RUNNING);
3043	remove_wait_queue(&journal->j_join_wait, &wait);
3044}
3045
3046static void wake_queued_writers(struct super_block *s)
3047{
3048	struct reiserfs_journal *journal = SB_JOURNAL(s);
3049	if (test_and_clear_bit(J_WRITERS_QUEUED, &journal->j_state))
3050		wake_up(&journal->j_join_wait);
3051}
3052
3053static void let_transaction_grow(struct super_block *sb, unsigned int trans_id)
3054{
3055	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3056	unsigned long bcount = journal->j_bcount;
3057	while (1) {
3058		reiserfs_write_unlock(sb);
3059		schedule_timeout_uninterruptible(1);
3060		reiserfs_write_lock(sb);
3061		journal->j_current_jl->j_state |= LIST_COMMIT_PENDING;
3062		while ((atomic_read(&journal->j_wcount) > 0 ||
3063			atomic_read(&journal->j_jlock)) &&
3064		       journal->j_trans_id == trans_id) {
3065			queue_log_writer(sb);
3066		}
3067		if (journal->j_trans_id != trans_id)
3068			break;
3069		if (bcount == journal->j_bcount)
3070			break;
3071		bcount = journal->j_bcount;
3072	}
3073}
3074
3075/* join == true if you must join an existing transaction.
3076** join == false if you can deal with waiting for others to finish
3077**
3078** this will block until the transaction is joinable.  send the number of blocks you
3079** expect to use in nblocks.
3080*/
3081static int do_journal_begin_r(struct reiserfs_transaction_handle *th,
3082			      struct super_block *sb, unsigned long nblocks,
3083			      int join)
3084{
3085	time_t now = get_seconds();
3086	unsigned int old_trans_id;
3087	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3088	struct reiserfs_transaction_handle myth;
3089	int sched_count = 0;
3090	int retval;
3091
3092	reiserfs_check_lock_depth(sb, "journal_begin");
3093	BUG_ON(nblocks > journal->j_trans_max);
3094
3095	PROC_INFO_INC(sb, journal.journal_being);
3096	/* set here for journal_join */
3097	th->t_refcount = 1;
3098	th->t_super = sb;
3099
3100      relock:
3101	lock_journal(sb);
3102	if (join != JBEGIN_ABORT && reiserfs_is_journal_aborted(journal)) {
3103		unlock_journal(sb);
3104		retval = journal->j_errno;
3105		goto out_fail;
3106	}
3107	journal->j_bcount++;
3108
3109	if (test_bit(J_WRITERS_BLOCKED, &journal->j_state)) {
3110		unlock_journal(sb);
3111		reiserfs_write_unlock(sb);
3112		reiserfs_wait_on_write_block(sb);
3113		reiserfs_write_lock(sb);
3114		PROC_INFO_INC(sb, journal.journal_relock_writers);
3115		goto relock;
3116	}
3117	now = get_seconds();
3118
3119	/* if there is no room in the journal OR
3120	 ** if this transaction is too old, and we weren't called joinable, wait for it to finish before beginning
3121	 ** we don't sleep if there aren't other writers
3122	 */
3123
3124	if ((!join && journal->j_must_wait > 0) ||
3125	    (!join
3126	     && (journal->j_len_alloc + nblocks + 2) >= journal->j_max_batch)
3127	    || (!join && atomic_read(&journal->j_wcount) > 0
3128		&& journal->j_trans_start_time > 0
3129		&& (now - journal->j_trans_start_time) >
3130		journal->j_max_trans_age) || (!join
3131					      && atomic_read(&journal->j_jlock))
3132	    || (!join && journal->j_cnode_free < (journal->j_trans_max * 3))) {
3133
3134		old_trans_id = journal->j_trans_id;
3135		unlock_journal(sb);	/* allow others to finish this transaction */
3136
3137		if (!join && (journal->j_len_alloc + nblocks + 2) >=
3138		    journal->j_max_batch &&
3139		    ((journal->j_len + nblocks + 2) * 100) <
3140		    (journal->j_len_alloc * 75)) {
3141			if (atomic_read(&journal->j_wcount) > 10) {
3142				sched_count++;
3143				queue_log_writer(sb);
3144				goto relock;
3145			}
3146		}
3147		/* don't mess with joining the transaction if all we have to do is
3148		 * wait for someone else to do a commit
3149		 */
3150		if (atomic_read(&journal->j_jlock)) {
3151			while (journal->j_trans_id == old_trans_id &&
3152			       atomic_read(&journal->j_jlock)) {
3153				queue_log_writer(sb);
3154			}
3155			goto relock;
3156		}
3157		retval = journal_join(&myth, sb, 1);
3158		if (retval)
3159			goto out_fail;
3160
3161		/* someone might have ended the transaction while we joined */
3162		if (old_trans_id != journal->j_trans_id) {
3163			retval = do_journal_end(&myth, sb, 1, 0);
3164		} else {
3165			retval = do_journal_end(&myth, sb, 1, COMMIT_NOW);
3166		}
3167
3168		if (retval)
3169			goto out_fail;
3170
3171		PROC_INFO_INC(sb, journal.journal_relock_wcount);
3172		goto relock;
3173	}
3174	/* we are the first writer, set trans_id */
3175	if (journal->j_trans_start_time == 0) {
3176		journal->j_trans_start_time = get_seconds();
3177	}
3178	atomic_inc(&(journal->j_wcount));
3179	journal->j_len_alloc += nblocks;
3180	th->t_blocks_logged = 0;
3181	th->t_blocks_allocated = nblocks;
3182	th->t_trans_id = journal->j_trans_id;
3183	unlock_journal(sb);
3184	INIT_LIST_HEAD(&th->t_list);
3185	get_fs_excl();
3186	return 0;
3187
3188      out_fail:
3189	memset(th, 0, sizeof(*th));
3190	/* Re-set th->t_super, so we can properly keep track of how many
3191	 * persistent transactions there are. We need to do this so if this
3192	 * call is part of a failed restart_transaction, we can free it later */
3193	th->t_super = sb;
3194	return retval;
3195}
3196
3197struct reiserfs_transaction_handle *reiserfs_persistent_transaction(struct
3198								    super_block
3199								    *s,
3200								    int nblocks)
3201{
3202	int ret;
3203	struct reiserfs_transaction_handle *th;
3204
3205	/* if we're nesting into an existing transaction.  It will be
3206	 ** persistent on its own
3207	 */
3208	if (reiserfs_transaction_running(s)) {
3209		th = current->journal_info;
3210		th->t_refcount++;
3211		BUG_ON(th->t_refcount < 2);
3212
3213		return th;
3214	}
3215	th = kmalloc(sizeof(struct reiserfs_transaction_handle), GFP_NOFS);
3216	if (!th)
3217		return NULL;
3218	ret = journal_begin(th, s, nblocks);
3219	if (ret) {
3220		kfree(th);
3221		return NULL;
3222	}
3223
3224	SB_JOURNAL(s)->j_persistent_trans++;
3225	return th;
3226}
3227
3228int reiserfs_end_persistent_transaction(struct reiserfs_transaction_handle *th)
3229{
3230	struct super_block *s = th->t_super;
3231	int ret = 0;
3232	if (th->t_trans_id)
3233		ret = journal_end(th, th->t_super, th->t_blocks_allocated);
3234	else
3235		ret = -EIO;
3236	if (th->t_refcount == 0) {
3237		SB_JOURNAL(s)->j_persistent_trans--;
3238		kfree(th);
3239	}
3240	return ret;
3241}
3242
3243static int journal_join(struct reiserfs_transaction_handle *th,
3244			struct super_block *sb, unsigned long nblocks)
3245{
3246	struct reiserfs_transaction_handle *cur_th = current->journal_info;
3247
3248	/* this keeps do_journal_end from NULLing out the current->journal_info
3249	 ** pointer
3250	 */
3251	th->t_handle_save = cur_th;
3252	BUG_ON(cur_th && cur_th->t_refcount > 1);
3253	return do_journal_begin_r(th, sb, nblocks, JBEGIN_JOIN);
3254}
3255
3256int journal_join_abort(struct reiserfs_transaction_handle *th,
3257		       struct super_block *sb, unsigned long nblocks)
3258{
3259	struct reiserfs_transaction_handle *cur_th = current->journal_info;
3260
3261	/* this keeps do_journal_end from NULLing out the current->journal_info
3262	 ** pointer
3263	 */
3264	th->t_handle_save = cur_th;
3265	BUG_ON(cur_th && cur_th->t_refcount > 1);
3266	return do_journal_begin_r(th, sb, nblocks, JBEGIN_ABORT);
3267}
3268
3269int journal_begin(struct reiserfs_transaction_handle *th,
3270		  struct super_block *sb, unsigned long nblocks)
3271{
3272	struct reiserfs_transaction_handle *cur_th = current->journal_info;
3273	int ret;
3274
3275	th->t_handle_save = NULL;
3276	if (cur_th) {
3277		/* we are nesting into the current transaction */
3278		if (cur_th->t_super == sb) {
3279			BUG_ON(!cur_th->t_refcount);
3280			cur_th->t_refcount++;
3281			memcpy(th, cur_th, sizeof(*th));
3282			if (th->t_refcount <= 1)
3283				reiserfs_warning(sb, "reiserfs-2005",
3284						 "BAD: refcount <= 1, but "
3285						 "journal_info != 0");
3286			return 0;
3287		} else {
3288			/* we've ended up with a handle from a different filesystem.
3289			 ** save it and restore on journal_end.  This should never
3290			 ** really happen...
3291			 */
3292			reiserfs_warning(sb, "clm-2100",
3293					 "nesting info a different FS");
3294			th->t_handle_save = current->journal_info;
3295			current->journal_info = th;
3296		}
3297	} else {
3298		current->journal_info = th;
3299	}
3300	ret = do_journal_begin_r(th, sb, nblocks, JBEGIN_REG);
3301	BUG_ON(current->journal_info != th);
3302
3303	/* I guess this boils down to being the reciprocal of clm-2100 above.
3304	 * If do_journal_begin_r fails, we need to put it back, since journal_end
3305	 * won't be called to do it. */
3306	if (ret)
3307		current->journal_info = th->t_handle_save;
3308	else
3309		BUG_ON(!th->t_refcount);
3310
3311	return ret;
3312}
3313
3314/*
3315** puts bh into the current transaction.  If it was already there, reorders removes the
3316** old pointers from the hash, and puts new ones in (to make sure replay happen in the right order).
3317**
3318** if it was dirty, cleans and files onto the clean list.  I can't let it be dirty again until the
3319** transaction is committed.
3320**
3321** if j_len, is bigger than j_len_alloc, it pushes j_len_alloc to 10 + j_len.
3322*/
3323int journal_mark_dirty(struct reiserfs_transaction_handle *th,
3324		       struct super_block *sb, struct buffer_head *bh)
3325{
3326	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3327	struct reiserfs_journal_cnode *cn = NULL;
3328	int count_already_incd = 0;
3329	int prepared = 0;
3330	BUG_ON(!th->t_trans_id);
3331
3332	PROC_INFO_INC(sb, journal.mark_dirty);
3333	if (th->t_trans_id != journal->j_trans_id) {
3334		reiserfs_panic(th->t_super, "journal-1577",
3335			       "handle trans id %ld != current trans id %ld",
3336			       th->t_trans_id, journal->j_trans_id);
3337	}
3338
3339	sb->s_dirt = 1;
3340
3341	prepared = test_clear_buffer_journal_prepared(bh);
3342	clear_buffer_journal_restore_dirty(bh);
3343	/* already in this transaction, we are done */
3344	if (buffer_journaled(bh)) {
3345		PROC_INFO_INC(sb, journal.mark_dirty_already);
3346		return 0;
3347	}
3348
3349	/* this must be turned into a panic instead of a warning.  We can't allow
3350	 ** a dirty or journal_dirty or locked buffer to be logged, as some changes
3351	 ** could get to disk too early.  NOT GOOD.
3352	 */
3353	if (!prepared || buffer_dirty(bh)) {
3354		reiserfs_warning(sb, "journal-1777",
3355				 "buffer %llu bad state "
3356				 "%cPREPARED %cLOCKED %cDIRTY %cJDIRTY_WAIT",
3357				 (unsigned long long)bh->b_blocknr,
3358				 prepared ? ' ' : '!',
3359				 buffer_locked(bh) ? ' ' : '!',
3360				 buffer_dirty(bh) ? ' ' : '!',
3361				 buffer_journal_dirty(bh) ? ' ' : '!');
3362	}
3363
3364	if (atomic_read(&(journal->j_wcount)) <= 0) {
3365		reiserfs_warning(sb, "journal-1409",
3366				 "returning because j_wcount was %d",
3367				 atomic_read(&(journal->j_wcount)));
3368		return 1;
3369	}
3370	/* this error means I've screwed up, and we've overflowed the transaction.
3371	 ** Nothing can be done here, except make the FS readonly or panic.
3372	 */
3373	if (journal->j_len >= journal->j_trans_max) {
3374		reiserfs_panic(th->t_super, "journal-1413",
3375			       "j_len (%lu) is too big",
3376			       journal->j_len);
3377	}
3378
3379	if (buffer_journal_dirty(bh)) {
3380		count_already_incd = 1;
3381		PROC_INFO_INC(sb, journal.mark_dirty_notjournal);
3382		clear_buffer_journal_dirty(bh);
3383	}
3384
3385	if (journal->j_len > journal->j_len_alloc) {
3386		journal->j_len_alloc = journal->j_len + JOURNAL_PER_BALANCE_CNT;
3387	}
3388
3389	set_buffer_journaled(bh);
3390
3391	/* now put this guy on the end */
3392	if (!cn) {
3393		cn = get_cnode(sb);
3394		if (!cn) {
3395			reiserfs_panic(sb, "journal-4", "get_cnode failed!");
3396		}
3397
3398		if (th->t_blocks_logged == th->t_blocks_allocated) {
3399			th->t_blocks_allocated += JOURNAL_PER_BALANCE_CNT;
3400			journal->j_len_alloc += JOURNAL_PER_BALANCE_CNT;
3401		}
3402		th->t_blocks_logged++;
3403		journal->j_len++;
3404
3405		cn->bh = bh;
3406		cn->blocknr = bh->b_blocknr;
3407		cn->sb = sb;
3408		cn->jlist = NULL;
3409		insert_journal_hash(journal->j_hash_table, cn);
3410		if (!count_already_incd) {
3411			get_bh(bh);
3412		}
3413	}
3414	cn->next = NULL;
3415	cn->prev = journal->j_last;
3416	cn->bh = bh;
3417	if (journal->j_last) {
3418		journal->j_last->next = cn;
3419		journal->j_last = cn;
3420	} else {
3421		journal->j_first = cn;
3422		journal->j_last = cn;
3423	}
3424	return 0;
3425}
3426
3427int journal_end(struct reiserfs_transaction_handle *th,
3428		struct super_block *sb, unsigned long nblocks)
3429{
3430	if (!current->journal_info && th->t_refcount > 1)
3431		reiserfs_warning(sb, "REISER-NESTING",
3432				 "th NULL, refcount %d", th->t_refcount);
3433
3434	if (!th->t_trans_id) {
3435		WARN_ON(1);
3436		return -EIO;
3437	}
3438
3439	th->t_refcount--;
3440	if (th->t_refcount > 0) {
3441		struct reiserfs_transaction_handle *cur_th =
3442		    current->journal_info;
3443
3444		/* we aren't allowed to close a nested transaction on a different
3445		 ** filesystem from the one in the task struct
3446		 */
3447		BUG_ON(cur_th->t_super != th->t_super);
3448
3449		if (th != cur_th) {
3450			memcpy(current->journal_info, th, sizeof(*th));
3451			th->t_trans_id = 0;
3452		}
3453		return 0;
3454	} else {
3455		return do_journal_end(th, sb, nblocks, 0);
3456	}
3457}
3458
3459/* removes from the current transaction, relsing and descrementing any counters.
3460** also files the removed buffer directly onto the clean list
3461**
3462** called by journal_mark_freed when a block has been deleted
3463**
3464** returns 1 if it cleaned and relsed the buffer. 0 otherwise
3465*/
3466static int remove_from_transaction(struct super_block *sb,
3467				   b_blocknr_t blocknr, int already_cleaned)
3468{
3469	struct buffer_head *bh;
3470	struct reiserfs_journal_cnode *cn;
3471	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3472	int ret = 0;
3473
3474	cn = get_journal_hash_dev(sb, journal->j_hash_table, blocknr);
3475	if (!cn || !cn->bh) {
3476		return ret;
3477	}
3478	bh = cn->bh;
3479	if (cn->prev) {
3480		cn->prev->next = cn->next;
3481	}
3482	if (cn->next) {
3483		cn->next->prev = cn->prev;
3484	}
3485	if (cn == journal->j_first) {
3486		journal->j_first = cn->next;
3487	}
3488	if (cn == journal->j_last) {
3489		journal->j_last = cn->prev;
3490	}
3491	if (bh)
3492		remove_journal_hash(sb, journal->j_hash_table, NULL,
3493				    bh->b_blocknr, 0);
3494	clear_buffer_journaled(bh);	/* don't log this one */
3495
3496	if (!already_cleaned) {
3497		clear_buffer_journal_dirty(bh);
3498		clear_buffer_dirty(bh);
3499		clear_buffer_journal_test(bh);
3500		put_bh(bh);
3501		if (atomic_read(&(bh->b_count)) < 0) {
3502			reiserfs_warning(sb, "journal-1752",
3503					 "b_count < 0");
3504		}
3505		ret = 1;
3506	}
3507	journal->j_len--;
3508	journal->j_len_alloc--;
3509	free_cnode(sb, cn);
3510	return ret;
3511}
3512
3513/*
3514** for any cnode in a journal list, it can only be dirtied of all the
3515** transactions that include it are committed to disk.
3516** this checks through each transaction, and returns 1 if you are allowed to dirty,
3517** and 0 if you aren't
3518**
3519** it is called by dirty_journal_list, which is called after flush_commit_list has gotten all the log
3520** blocks for a given transaction on disk
3521**
3522*/
3523static int can_dirty(struct reiserfs_journal_cnode *cn)
3524{
3525	struct super_block *sb = cn->sb;
3526	b_blocknr_t blocknr = cn->blocknr;
3527	struct reiserfs_journal_cnode *cur = cn->hprev;
3528	int can_dirty = 1;
3529
3530	/* first test hprev.  These are all newer than cn, so any node here
3531	 ** with the same block number and dev means this node can't be sent
3532	 ** to disk right now.
3533	 */
3534	while (cur && can_dirty) {
3535		if (cur->jlist && cur->bh && cur->blocknr && cur->sb == sb &&
3536		    cur->blocknr == blocknr) {
3537			can_dirty = 0;
3538		}
3539		cur = cur->hprev;
3540	}
3541	/* then test hnext.  These are all older than cn.  As long as they
3542	 ** are committed to the log, it is safe to write cn to disk
3543	 */
3544	cur = cn->hnext;
3545	while (cur && can_dirty) {
3546		if (cur->jlist && cur->jlist->j_len > 0 &&
3547		    atomic_read(&(cur->jlist->j_commit_left)) > 0 && cur->bh &&
3548		    cur->blocknr && cur->sb == sb && cur->blocknr == blocknr) {
3549			can_dirty = 0;
3550		}
3551		cur = cur->hnext;
3552	}
3553	return can_dirty;
3554}
3555
3556/* syncs the commit blocks, but does not force the real buffers to disk
3557** will wait until the current transaction is done/committed before returning
3558*/
3559int journal_end_sync(struct reiserfs_transaction_handle *th,
3560		     struct super_block *sb, unsigned long nblocks)
3561{
3562	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3563
3564	BUG_ON(!th->t_trans_id);
3565	/* you can sync while nested, very, very bad */
3566	BUG_ON(th->t_refcount > 1);
3567	if (journal->j_len == 0) {
3568		reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
3569					     1);
3570		journal_mark_dirty(th, sb, SB_BUFFER_WITH_SB(sb));
3571	}
3572	return do_journal_end(th, sb, nblocks, COMMIT_NOW | WAIT);
3573}
3574
3575/*
3576** writeback the pending async commits to disk
3577*/
3578static void flush_async_commits(struct work_struct *work)
3579{
3580	struct reiserfs_journal *journal =
3581		container_of(work, struct reiserfs_journal, j_work.work);
3582	struct super_block *sb = journal->j_work_sb;
3583	struct reiserfs_journal_list *jl;
3584	struct list_head *entry;
3585
3586	reiserfs_write_lock(sb);
3587	if (!list_empty(&journal->j_journal_list)) {
3588		/* last entry is the youngest, commit it and you get everything */
3589		entry = journal->j_journal_list.prev;
3590		jl = JOURNAL_LIST_ENTRY(entry);
3591		flush_commit_list(sb, jl, 1);
3592	}
3593	reiserfs_write_unlock(sb);
3594}
3595
3596/*
3597** flushes any old transactions to disk
3598** ends the current transaction if it is too old
3599*/
3600int reiserfs_flush_old_commits(struct super_block *sb)
3601{
3602	time_t now;
3603	struct reiserfs_transaction_handle th;
3604	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3605
3606	now = get_seconds();
3607	/* safety check so we don't flush while we are replaying the log during
3608	 * mount
3609	 */
3610	if (list_empty(&journal->j_journal_list)) {
3611		return 0;
3612	}
3613
3614	/* check the current transaction.  If there are no writers, and it is
3615	 * too old, finish it, and force the commit blocks to disk
3616	 */
3617	if (atomic_read(&journal->j_wcount) <= 0 &&
3618	    journal->j_trans_start_time > 0 &&
3619	    journal->j_len > 0 &&
3620	    (now - journal->j_trans_start_time) > journal->j_max_trans_age) {
3621		if (!journal_join(&th, sb, 1)) {
3622			reiserfs_prepare_for_journal(sb,
3623						     SB_BUFFER_WITH_SB(sb),
3624						     1);
3625			journal_mark_dirty(&th, sb,
3626					   SB_BUFFER_WITH_SB(sb));
3627
3628			/* we're only being called from kreiserfsd, it makes no sense to do
3629			 ** an async commit so that kreiserfsd can do it later
3630			 */
3631			do_journal_end(&th, sb, 1, COMMIT_NOW | WAIT);
3632		}
3633	}
3634	return sb->s_dirt;
3635}
3636
3637/*
3638** returns 0 if do_journal_end should return right away, returns 1 if do_journal_end should finish the commit
3639**
3640** if the current transaction is too old, but still has writers, this will wait on j_join_wait until all
3641** the writers are done.  By the time it wakes up, the transaction it was called has already ended, so it just
3642** flushes the commit list and returns 0.
3643**
3644** Won't batch when flush or commit_now is set.  Also won't batch when others are waiting on j_join_wait.
3645**
3646** Note, we can't allow the journal_end to proceed while there are still writers in the log.
3647*/
3648static int check_journal_end(struct reiserfs_transaction_handle *th,
3649			     struct super_block *sb, unsigned long nblocks,
3650			     int flags)
3651{
3652
3653	time_t now;
3654	int flush = flags & FLUSH_ALL;
3655	int commit_now = flags & COMMIT_NOW;
3656	int wait_on_commit = flags & WAIT;
3657	struct reiserfs_journal_list *jl;
3658	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3659
3660	BUG_ON(!th->t_trans_id);
3661
3662	if (th->t_trans_id != journal->j_trans_id) {
3663		reiserfs_panic(th->t_super, "journal-1577",
3664			       "handle trans id %ld != current trans id %ld",
3665			       th->t_trans_id, journal->j_trans_id);
3666	}
3667
3668	journal->j_len_alloc -= (th->t_blocks_allocated - th->t_blocks_logged);
3669	if (atomic_read(&(journal->j_wcount)) > 0) {	/* <= 0 is allowed.  unmounting might not call begin */
3670		atomic_dec(&(journal->j_wcount));
3671	}
3672
3673	/* BUG, deal with case where j_len is 0, but people previously freed blocks need to be released
3674	 ** will be dealt with by next transaction that actually writes something, but should be taken
3675	 ** care of in this trans
3676	 */
3677	BUG_ON(journal->j_len == 0);
3678
3679	/* if wcount > 0, and we are called to with flush or commit_now,
3680	 ** we wait on j_join_wait.  We will wake up when the last writer has
3681	 ** finished the transaction, and started it on its way to the disk.
3682	 ** Then, we flush the commit or journal list, and just return 0
3683	 ** because the rest of journal end was already done for this transaction.
3684	 */
3685	if (atomic_read(&(journal->j_wcount)) > 0) {
3686		if (flush || commit_now) {
3687			unsigned trans_id;
3688
3689			jl = journal->j_current_jl;
3690			trans_id = jl->j_trans_id;
3691			if (wait_on_commit)
3692				jl->j_state |= LIST_COMMIT_PENDING;
3693			atomic_set(&(journal->j_jlock), 1);
3694			if (flush) {
3695				journal->j_next_full_flush = 1;
3696			}
3697			unlock_journal(sb);
3698
3699			/* sleep while the current transaction is still j_jlocked */
3700			while (journal->j_trans_id == trans_id) {
3701				if (atomic_read(&journal->j_jlock)) {
3702					queue_log_writer(sb);
3703				} else {
3704					lock_journal(sb);
3705					if (journal->j_trans_id == trans_id) {
3706						atomic_set(&(journal->j_jlock),
3707							   1);
3708					}
3709					unlock_journal(sb);
3710				}
3711			}
3712			BUG_ON(journal->j_trans_id == trans_id);
3713
3714			if (commit_now
3715			    && journal_list_still_alive(sb, trans_id)
3716			    && wait_on_commit) {
3717				flush_commit_list(sb, jl, 1);
3718			}
3719			return 0;
3720		}
3721		unlock_journal(sb);
3722		return 0;
3723	}
3724
3725	/* deal with old transactions where we are the last writers */
3726	now = get_seconds();
3727	if ((now - journal->j_trans_start_time) > journal->j_max_trans_age) {
3728		commit_now = 1;
3729		journal->j_next_async_flush = 1;
3730	}
3731	/* don't batch when someone is waiting on j_join_wait */
3732	/* don't batch when syncing the commit or flushing the whole trans */
3733	if (!(journal->j_must_wait > 0) && !(atomic_read(&(journal->j_jlock)))
3734	    && !flush && !commit_now && (journal->j_len < journal->j_max_batch)
3735	    && journal->j_len_alloc < journal->j_max_batch
3736	    && journal->j_cnode_free > (journal->j_trans_max * 3)) {
3737		journal->j_bcount++;
3738		unlock_journal(sb);
3739		return 0;
3740	}
3741
3742	if (journal->j_start > SB_ONDISK_JOURNAL_SIZE(sb)) {
3743		reiserfs_panic(sb, "journal-003",
3744			       "j_start (%ld) is too high",
3745			       journal->j_start);
3746	}
3747	return 1;
3748}
3749
3750/*
3751** Does all the work that makes deleting blocks safe.
3752** when deleting a block mark BH_JNew, just remove it from the current transaction, clean it's buffer_head and move on.
3753**
3754** otherwise:
3755** set a bit for the block in the journal bitmap.  That will prevent it from being allocated for unformatted nodes
3756** before this transaction has finished.
3757**
3758** mark any cnodes for this block as BLOCK_FREED, and clear their bh pointers.  That will prevent any old transactions with
3759** this block from trying to flush to the real location.  Since we aren't removing the cnode from the journal_list_hash,
3760** the block can't be reallocated yet.
3761**
3762** Then remove it from the current transaction, decrementing any counters and filing it on the clean list.
3763*/
3764int journal_mark_freed(struct reiserfs_transaction_handle *th,
3765		       struct super_block *sb, b_blocknr_t blocknr)
3766{
3767	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3768	struct reiserfs_journal_cnode *cn = NULL;
3769	struct buffer_head *bh = NULL;
3770	struct reiserfs_list_bitmap *jb = NULL;
3771	int cleaned = 0;
3772	BUG_ON(!th->t_trans_id);
3773
3774	cn = get_journal_hash_dev(sb, journal->j_hash_table, blocknr);
3775	if (cn && cn->bh) {
3776		bh = cn->bh;
3777		get_bh(bh);
3778	}
3779	/* if it is journal new, we just remove it from this transaction */
3780	if (bh && buffer_journal_new(bh)) {
3781		clear_buffer_journal_new(bh);
3782		clear_prepared_bits(bh);
3783		reiserfs_clean_and_file_buffer(bh);
3784		cleaned = remove_from_transaction(sb, blocknr, cleaned);
3785	} else {
3786		/* set the bit for this block in the journal bitmap for this transaction */
3787		jb = journal->j_current_jl->j_list_bitmap;
3788		if (!jb) {
3789			reiserfs_panic(sb, "journal-1702",
3790				       "journal_list_bitmap is NULL");
3791		}
3792		set_bit_in_list_bitmap(sb, blocknr, jb);
3793
3794		/* Note, the entire while loop is not allowed to schedule.  */
3795
3796		if (bh) {
3797			clear_prepared_bits(bh);
3798			reiserfs_clean_and_file_buffer(bh);
3799		}
3800		cleaned = remove_from_transaction(sb, blocknr, cleaned);
3801
3802		/* find all older transactions with this block, make sure they don't try to write it out */
3803		cn = get_journal_hash_dev(sb, journal->j_list_hash_table,
3804					  blocknr);
3805		while (cn) {
3806			if (sb == cn->sb && blocknr == cn->blocknr) {
3807				set_bit(BLOCK_FREED, &cn->state);
3808				if (cn->bh) {
3809					if (!cleaned) {
3810						/* remove_from_transaction will brelse the buffer if it was
3811						 ** in the current trans
3812						 */
3813						clear_buffer_journal_dirty(cn->
3814									   bh);
3815						clear_buffer_dirty(cn->bh);
3816						clear_buffer_journal_test(cn->
3817									  bh);
3818						cleaned = 1;
3819						put_bh(cn->bh);
3820						if (atomic_read
3821						    (&(cn->bh->b_count)) < 0) {
3822							reiserfs_warning(sb,
3823								 "journal-2138",
3824								 "cn->bh->b_count < 0");
3825						}
3826					}
3827					if (cn->jlist) {	/* since we are clearing the bh, we MUST dec nonzerolen */
3828						atomic_dec(&
3829							   (cn->jlist->
3830							    j_nonzerolen));
3831					}
3832					cn->bh = NULL;
3833				}
3834			}
3835			cn = cn->hnext;
3836		}
3837	}
3838
3839	if (bh)
3840		release_buffer_page(bh); /* get_hash grabs the buffer */
3841	return 0;
3842}
3843
3844void reiserfs_update_inode_transaction(struct inode *inode)
3845{
3846	struct reiserfs_journal *journal = SB_JOURNAL(inode->i_sb);
3847	REISERFS_I(inode)->i_jl = journal->j_current_jl;
3848	REISERFS_I(inode)->i_trans_id = journal->j_trans_id;
3849}
3850
3851/*
3852 * returns -1 on error, 0 if no commits/barriers were done and 1
3853 * if a transaction was actually committed and the barrier was done
3854 */
3855static int __commit_trans_jl(struct inode *inode, unsigned long id,
3856			     struct reiserfs_journal_list *jl)
3857{
3858	struct reiserfs_transaction_handle th;
3859	struct super_block *sb = inode->i_sb;
3860	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3861	int ret = 0;
3862
3863	/* is it from the current transaction, or from an unknown transaction? */
3864	if (id == journal->j_trans_id) {
3865		jl = journal->j_current_jl;
3866		/* try to let other writers come in and grow this transaction */
3867		let_transaction_grow(sb, id);
3868		if (journal->j_trans_id != id) {
3869			goto flush_commit_only;
3870		}
3871
3872		ret = journal_begin(&th, sb, 1);
3873		if (ret)
3874			return ret;
3875
3876		/* someone might have ended this transaction while we joined */
3877		if (journal->j_trans_id != id) {
3878			reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
3879						     1);
3880			journal_mark_dirty(&th, sb, SB_BUFFER_WITH_SB(sb));
3881			ret = journal_end(&th, sb, 1);
3882			goto flush_commit_only;
3883		}
3884
3885		ret = journal_end_sync(&th, sb, 1);
3886		if (!ret)
3887			ret = 1;
3888
3889	} else {
3890		/* this gets tricky, we have to make sure the journal list in
3891		 * the inode still exists.  We know the list is still around
3892		 * if we've got a larger transaction id than the oldest list
3893		 */
3894	      flush_commit_only:
3895		if (journal_list_still_alive(inode->i_sb, id)) {
3896			/*
3897			 * we only set ret to 1 when we know for sure
3898			 * the barrier hasn't been started yet on the commit
3899			 * block.
3900			 */
3901			if (atomic_read(&jl->j_commit_left) > 1)
3902				ret = 1;
3903			flush_commit_list(sb, jl, 1);
3904			if (journal->j_errno)
3905				ret = journal->j_errno;
3906		}
3907	}
3908	/* otherwise the list is gone, and long since committed */
3909	return ret;
3910}
3911
3912int reiserfs_commit_for_inode(struct inode *inode)
3913{
3914	unsigned int id = REISERFS_I(inode)->i_trans_id;
3915	struct reiserfs_journal_list *jl = REISERFS_I(inode)->i_jl;
3916
3917	/* for the whole inode, assume unset id means it was
3918	 * changed in the current transaction.  More conservative
3919	 */
3920	if (!id || !jl) {
3921		reiserfs_update_inode_transaction(inode);
3922		id = REISERFS_I(inode)->i_trans_id;
3923		/* jl will be updated in __commit_trans_jl */
3924	}
3925
3926	return __commit_trans_jl(inode, id, jl);
3927}
3928
3929void reiserfs_restore_prepared_buffer(struct super_block *sb,
3930				      struct buffer_head *bh)
3931{
3932	struct reiserfs_journal *journal = SB_JOURNAL(sb);
3933	PROC_INFO_INC(sb, journal.restore_prepared);
3934	if (!bh) {
3935		return;
3936	}
3937	if (test_clear_buffer_journal_restore_dirty(bh) &&
3938	    buffer_journal_dirty(bh)) {
3939		struct reiserfs_journal_cnode *cn;
3940		cn = get_journal_hash_dev(sb,
3941					  journal->j_list_hash_table,
3942					  bh->b_blocknr);
3943		if (cn && can_dirty(cn)) {
3944			set_buffer_journal_test(bh);
3945			mark_buffer_dirty(bh);
3946		}
3947	}
3948	clear_buffer_journal_prepared(bh);
3949}
3950
3951extern struct tree_balance *cur_tb;
3952/*
3953** before we can change a metadata block, we have to make sure it won't
3954** be written to disk while we are altering it.  So, we must:
3955** clean it
3956** wait on it.
3957**
3958*/
3959int reiserfs_prepare_for_journal(struct super_block *sb,
3960				 struct buffer_head *bh, int wait)
3961{
3962	PROC_INFO_INC(sb, journal.prepare);
3963
3964	if (!trylock_buffer(bh)) {
3965		if (!wait)
3966			return 0;
3967		lock_buffer(bh);
3968	}
3969	set_buffer_journal_prepared(bh);
3970	if (test_clear_buffer_dirty(bh) && buffer_journal_dirty(bh)) {
3971		clear_buffer_journal_test(bh);
3972		set_buffer_journal_restore_dirty(bh);
3973	}
3974	unlock_buffer(bh);
3975	return 1;
3976}
3977
3978static void flush_old_journal_lists(struct super_block *s)
3979{
3980	struct reiserfs_journal *journal = SB_JOURNAL(s);
3981	struct reiserfs_journal_list *jl;
3982	struct list_head *entry;
3983	time_t now = get_seconds();
3984
3985	while (!list_empty(&journal->j_journal_list)) {
3986		entry = journal->j_journal_list.next;
3987		jl = JOURNAL_LIST_ENTRY(entry);
3988		/* this check should always be run, to send old lists to disk */
3989		if (jl->j_timestamp < (now - (JOURNAL_MAX_TRANS_AGE * 4)) &&
3990		    atomic_read(&jl->j_commit_left) == 0 &&
3991		    test_transaction(s, jl)) {
3992			flush_used_journal_lists(s, jl);
3993		} else {
3994			break;
3995		}
3996	}
3997}
3998
3999/*
4000** long and ugly.  If flush, will not return until all commit
4001** blocks and all real buffers in the trans are on disk.
4002** If no_async, won't return until all commit blocks are on disk.
4003**
4004** keep reading, there are comments as you go along
4005**
4006** If the journal is aborted, we just clean up. Things like flushing
4007** journal lists, etc just won't happen.
4008*/
4009static int do_journal_end(struct reiserfs_transaction_handle *th,
4010			  struct super_block *sb, unsigned long nblocks,
4011			  int flags)
4012{
4013	struct reiserfs_journal *journal = SB_JOURNAL(sb);
4014	struct reiserfs_journal_cnode *cn, *next, *jl_cn;
4015	struct reiserfs_journal_cnode *last_cn = NULL;
4016	struct reiserfs_journal_desc *desc;
4017	struct reiserfs_journal_commit *commit;
4018	struct buffer_head *c_bh;	/* commit bh */
4019	struct buffer_head *d_bh;	/* desc bh */
4020	int cur_write_start = 0;	/* start index of current log write */
4021	int old_start;
4022	int i;
4023	int flush;
4024	int wait_on_commit;
4025	struct reiserfs_journal_list *jl, *temp_jl;
4026	struct list_head *entry, *safe;
4027	unsigned long jindex;
4028	unsigned int commit_trans_id;
4029	int trans_half;
4030
4031	BUG_ON(th->t_refcount > 1);
4032	BUG_ON(!th->t_trans_id);
4033
4034	/* protect flush_older_commits from doing mistakes if the
4035           transaction ID counter gets overflowed.  */
4036	if (th->t_trans_id == ~0U)
4037		flags |= FLUSH_ALL | COMMIT_NOW | WAIT;
4038	flush = flags & FLUSH_ALL;
4039	wait_on_commit = flags & WAIT;
4040
4041	put_fs_excl();
4042	current->journal_info = th->t_handle_save;
4043	reiserfs_check_lock_depth(sb, "journal end");
4044	if (journal->j_len == 0) {
4045		reiserfs_prepare_for_journal(sb, SB_BUFFER_WITH_SB(sb),
4046					     1);
4047		journal_mark_dirty(th, sb, SB_BUFFER_WITH_SB(sb));
4048	}
4049
4050	lock_journal(sb);
4051	if (journal->j_next_full_flush) {
4052		flags |= FLUSH_ALL;
4053		flush = 1;
4054	}
4055	if (journal->j_next_async_flush) {
4056		flags |= COMMIT_NOW | WAIT;
4057		wait_on_commit = 1;
4058	}
4059
4060	/* check_journal_end locks the journal, and unlocks if it does not return 1
4061	 ** it tells us if we should continue with the journal_end, or just return
4062	 */
4063	if (!check_journal_end(th, sb, nblocks, flags)) {
4064		sb->s_dirt = 1;
4065		wake_queued_writers(sb);
4066		reiserfs_async_progress_wait(sb);
4067		goto out;
4068	}
4069
4070	/* check_journal_end might set these, check again */
4071	if (journal->j_next_full_flush) {
4072		flush = 1;
4073	}
4074
4075	/*
4076	 ** j must wait means we have to flush the log blocks, and the real blocks for
4077	 ** this transaction
4078	 */
4079	if (journal->j_must_wait > 0) {
4080		flush = 1;
4081	}
4082#ifdef REISERFS_PREALLOCATE
4083	/* quota ops might need to nest, setup the journal_info pointer for them
4084	 * and raise the refcount so that it is > 0. */
4085	current->journal_info = th;
4086	th->t_refcount++;
4087	reiserfs_discard_all_prealloc(th);	/* it should not involve new blocks into
4088						 * the transaction */
4089	th->t_refcount--;
4090	current->journal_info = th->t_handle_save;
4091#endif
4092
4093	/* setup description block */
4094	d_bh =
4095	    journal_getblk(sb,
4096			   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
4097			   journal->j_start);
4098	set_buffer_uptodate(d_bh);
4099	desc = (struct reiserfs_journal_desc *)(d_bh)->b_data;
4100	memset(d_bh->b_data, 0, d_bh->b_size);
4101	memcpy(get_journal_desc_magic(d_bh), JOURNAL_DESC_MAGIC, 8);
4102	set_desc_trans_id(desc, journal->j_trans_id);
4103
4104	/* setup commit block.  Don't write (keep it clean too) this one until after everyone else is written */
4105	c_bh = journal_getblk(sb, SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
4106			      ((journal->j_start + journal->j_len +
4107				1) % SB_ONDISK_JOURNAL_SIZE(sb)));
4108	commit = (struct reiserfs_journal_commit *)c_bh->b_data;
4109	memset(c_bh->b_data, 0, c_bh->b_size);
4110	set_commit_trans_id(commit, journal->j_trans_id);
4111	set_buffer_uptodate(c_bh);
4112
4113	/* init this journal list */
4114	jl = journal->j_current_jl;
4115
4116	/* we lock the commit before doing anything because
4117	 * we want to make sure nobody tries to run flush_commit_list until
4118	 * the new transaction is fully setup, and we've already flushed the
4119	 * ordered bh list
4120	 */
4121	reiserfs_mutex_lock_safe(&jl->j_commit_mutex, sb);
4122
4123	/* save the transaction id in case we need to commit it later */
4124	commit_trans_id = jl->j_trans_id;
4125
4126	atomic_set(&jl->j_older_commits_done, 0);
4127	jl->j_trans_id = journal->j_trans_id;
4128	jl->j_timestamp = journal->j_trans_start_time;
4129	jl->j_commit_bh = c_bh;
4130	jl->j_start = journal->j_start;
4131	jl->j_len = journal->j_len;
4132	atomic_set(&jl->j_nonzerolen, journal->j_len);
4133	atomic_set(&jl->j_commit_left, journal->j_len + 2);
4134	jl->j_realblock = NULL;
4135
4136	/* The ENTIRE FOR LOOP MUST not cause schedule to occur.
4137	 **  for each real block, add it to the journal list hash,
4138	 ** copy into real block index array in the commit or desc block
4139	 */
4140	trans_half = journal_trans_half(sb->s_blocksize);
4141	for (i = 0, cn = journal->j_first; cn; cn = cn->next, i++) {
4142		if (buffer_journaled(cn->bh)) {
4143			jl_cn = get_cnode(sb);
4144			if (!jl_cn) {
4145				reiserfs_panic(sb, "journal-1676",
4146					       "get_cnode returned NULL");
4147			}
4148			if (i == 0) {
4149				jl->j_realblock = jl_cn;
4150			}
4151			jl_cn->prev = last_cn;
4152			jl_cn->next = NULL;
4153			if (last_cn) {
4154				last_cn->next = jl_cn;
4155			}
4156			last_cn = jl_cn;
4157			/* make sure the block we are trying to log is not a block
4158			   of journal or reserved area */
4159
4160			if (is_block_in_log_or_reserved_area
4161			    (sb, cn->bh->b_blocknr)) {
4162				reiserfs_panic(sb, "journal-2332",
4163					       "Trying to log block %lu, "
4164					       "which is a log block",
4165					       cn->bh->b_blocknr);
4166			}
4167			jl_cn->blocknr = cn->bh->b_blocknr;
4168			jl_cn->state = 0;
4169			jl_cn->sb = sb;
4170			jl_cn->bh = cn->bh;
4171			jl_cn->jlist = jl;
4172			insert_journal_hash(journal->j_list_hash_table, jl_cn);
4173			if (i < trans_half) {
4174				desc->j_realblock[i] =
4175				    cpu_to_le32(cn->bh->b_blocknr);
4176			} else {
4177				commit->j_realblock[i - trans_half] =
4178				    cpu_to_le32(cn->bh->b_blocknr);
4179			}
4180		} else {
4181			i--;
4182		}
4183	}
4184	set_desc_trans_len(desc, journal->j_len);
4185	set_desc_mount_id(desc, journal->j_mount_id);
4186	set_desc_trans_id(desc, journal->j_trans_id);
4187	set_commit_trans_len(commit, journal->j_len);
4188
4189	/* special check in case all buffers in the journal were marked for not logging */
4190	BUG_ON(journal->j_len == 0);
4191
4192	/* we're about to dirty all the log blocks, mark the description block
4193	 * dirty now too.  Don't mark the commit block dirty until all the
4194	 * others are on disk
4195	 */
4196	mark_buffer_dirty(d_bh);
4197
4198	/* first data block is j_start + 1, so add one to cur_write_start wherever you use it */
4199	cur_write_start = journal->j_start;
4200	cn = journal->j_first;
4201	jindex = 1;		/* start at one so we don't get the desc again */
4202	while (cn) {
4203		clear_buffer_journal_new(cn->bh);
4204		/* copy all the real blocks into log area.  dirty log blocks */
4205		if (buffer_journaled(cn->bh)) {
4206			struct buffer_head *tmp_bh;
4207			char *addr;
4208			struct page *page;
4209			tmp_bh =
4210			    journal_getblk(sb,
4211					   SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
4212					   ((cur_write_start +
4213					     jindex) %
4214					    SB_ONDISK_JOURNAL_SIZE(sb)));
4215			set_buffer_uptodate(tmp_bh);
4216			page = cn->bh->b_page;
4217			addr = kmap(page);
4218			memcpy(tmp_bh->b_data,
4219			       addr + offset_in_page(cn->bh->b_data),
4220			       cn->bh->b_size);
4221			kunmap(page);
4222			mark_buffer_dirty(tmp_bh);
4223			jindex++;
4224			set_buffer_journal_dirty(cn->bh);
4225			clear_buffer_journaled(cn->bh);
4226		} else {
4227			/* JDirty cleared sometime during transaction.  don't log this one */
4228			reiserfs_warning(sb, "journal-2048",
4229					 "BAD, buffer in journal hash, "
4230					 "but not JDirty!");
4231			brelse(cn->bh);
4232		}
4233		next = cn->next;
4234		free_cnode(sb, cn);
4235		cn = next;
4236		reiserfs_write_unlock(sb);
4237		cond_resched();
4238		reiserfs_write_lock(sb);
4239	}
4240
4241	/* we are done  with both the c_bh and d_bh, but
4242	 ** c_bh must be written after all other commit blocks,
4243	 ** so we dirty/relse c_bh in flush_commit_list, with commit_left <= 1.
4244	 */
4245
4246	journal->j_current_jl = alloc_journal_list(sb);
4247
4248	/* now it is safe to insert this transaction on the main list */
4249	list_add_tail(&jl->j_list, &journal->j_journal_list);
4250	list_add_tail(&jl->j_working_list, &journal->j_working_list);
4251	journal->j_num_work_lists++;
4252
4253	/* reset journal values for the next transaction */
4254	old_start = journal->j_start;
4255	journal->j_start =
4256	    (journal->j_start + journal->j_len +
4257	     2) % SB_ONDISK_JOURNAL_SIZE(sb);
4258	atomic_set(&(journal->j_wcount), 0);
4259	journal->j_bcount = 0;
4260	journal->j_last = NULL;
4261	journal->j_first = NULL;
4262	journal->j_len = 0;
4263	journal->j_trans_start_time = 0;
4264	/* check for trans_id overflow */
4265	if (++journal->j_trans_id == 0)
4266		journal->j_trans_id = 10;
4267	journal->j_current_jl->j_trans_id = journal->j_trans_id;
4268	journal->j_must_wait = 0;
4269	journal->j_len_alloc = 0;
4270	journal->j_next_full_flush = 0;
4271	journal->j_next_async_flush = 0;
4272	init_journal_hash(sb);
4273
4274	// make sure reiserfs_add_jh sees the new current_jl before we
4275	// write out the tails
4276	smp_mb();
4277
4278	/* tail conversion targets have to hit the disk before we end the
4279	 * transaction.  Otherwise a later transaction might repack the tail
4280	 * before this transaction commits, leaving the data block unflushed and
4281	 * clean, if we crash before the later transaction commits, the data block
4282	 * is lost.
4283	 */
4284	if (!list_empty(&jl->j_tail_bh_list)) {
4285		reiserfs_write_unlock(sb);
4286		write_ordered_buffers(&journal->j_dirty_buffers_lock,
4287				      journal, jl, &jl->j_tail_bh_list);
4288		reiserfs_write_lock(sb);
4289	}
4290	BUG_ON(!list_empty(&jl->j_tail_bh_list));
4291	mutex_unlock(&jl->j_commit_mutex);
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		queue_delayed_work(commit_wq, &journal->j_work, HZ / 10);
4305
4306	/* if the next transaction has any chance of wrapping, flush
4307	 ** transactions that might get overwritten.  If any journal lists are very
4308	 ** old flush them as well.
4309	 */
4310      first_jl:
4311	list_for_each_safe(entry, safe, &journal->j_journal_list) {
4312		temp_jl = JOURNAL_LIST_ENTRY(entry);
4313		if (journal->j_start <= temp_jl->j_start) {
4314			if ((journal->j_start + journal->j_trans_max + 1) >=
4315			    temp_jl->j_start) {
4316				flush_used_journal_lists(sb, temp_jl);
4317				goto first_jl;
4318			} else if ((journal->j_start +
4319				    journal->j_trans_max + 1) <
4320				   SB_ONDISK_JOURNAL_SIZE(sb)) {
4321				/* if we don't cross into the next transaction and we don't
4322				 * wrap, there is no way we can overlap any later transactions
4323				 * break now
4324				 */
4325				break;
4326			}
4327		} else if ((journal->j_start +
4328			    journal->j_trans_max + 1) >
4329			   SB_ONDISK_JOURNAL_SIZE(sb)) {
4330			if (((journal->j_start + journal->j_trans_max + 1) %
4331			     SB_ONDISK_JOURNAL_SIZE(sb)) >=
4332			    temp_jl->j_start) {
4333				flush_used_journal_lists(sb, temp_jl);
4334				goto first_jl;
4335			} else {
4336				/* we don't overlap anything from out start to the end of the
4337				 * log, and our wrapped portion doesn't overlap anything at
4338				 * the start of the log.  We can break
4339				 */
4340				break;
4341			}
4342		}
4343	}
4344	flush_old_journal_lists(sb);
4345
4346	journal->j_current_jl->j_list_bitmap =
4347	    get_list_bitmap(sb, journal->j_current_jl);
4348
4349	if (!(journal->j_current_jl->j_list_bitmap)) {
4350		reiserfs_panic(sb, "journal-1996",
4351			       "could not get a list bitmap");
4352	}
4353
4354	atomic_set(&(journal->j_jlock), 0);
4355	unlock_journal(sb);
4356	/* wake up any body waiting to join. */
4357	clear_bit(J_WRITERS_QUEUED, &journal->j_state);
4358	wake_up(&(journal->j_join_wait));
4359
4360	if (!flush && wait_on_commit &&
4361	    journal_list_still_alive(sb, commit_trans_id)) {
4362		flush_commit_list(sb, jl, 1);
4363	}
4364      out:
4365	reiserfs_check_lock_depth(sb, "journal end2");
4366
4367	memset(th, 0, sizeof(*th));
4368	/* Re-set th->t_super, so we can properly keep track of how many
4369	 * persistent transactions there are. We need to do this so if this
4370	 * call is part of a failed restart_transaction, we can free it later */
4371	th->t_super = sb;
4372
4373	return journal->j_errno;
4374}
4375
4376/* Send the file system read only and refuse new transactions */
4377void reiserfs_abort_journal(struct super_block *sb, int errno)
4378{
4379	struct reiserfs_journal *journal = SB_JOURNAL(sb);
4380	if (test_bit(J_ABORTED, &journal->j_state))
4381		return;
4382
4383	if (!journal->j_errno)
4384		journal->j_errno = errno;
4385
4386	sb->s_flags |= MS_RDONLY;
4387	set_bit(J_ABORTED, &journal->j_state);
4388
4389#ifdef CONFIG_REISERFS_CHECK
4390	dump_stack();
4391#endif
4392}
4393