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