1 /*
2  *   Copyright (C) International Business Machines Corp., 2000-2004
3  *   Portions Copyright (C) Christoph Hellwig, 2001-2002
4  *
5  *   This program is free software;  you can redistribute it and/or modify
6  *   it under the terms of the GNU General Public License as published by
7  *   the Free Software Foundation; either version 2 of the License, or
8  *   (at your option) any later version.
9  *
10  *   This program is distributed in the hope that it will be useful,
11  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
13  *   the GNU General Public License for more details.
14  *
15  *   You should have received a copy of the GNU General Public License
16  *   along with this program;  if not, write to the Free Software
17  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18  */
19 
20 /*
21  *	jfs_logmgr.c: log manager
22  *
23  * for related information, see transaction manager (jfs_txnmgr.c), and
24  * recovery manager (jfs_logredo.c).
25  *
26  * note: for detail, RTFS.
27  *
28  *	log buffer manager:
29  * special purpose buffer manager supporting log i/o requirements.
30  * per log serial pageout of logpage
31  * queuing i/o requests and redrive i/o at iodone
32  * maintain current logpage buffer
33  * no caching since append only
34  * appropriate jfs buffer cache buffers as needed
35  *
36  *	group commit:
37  * transactions which wrote COMMIT records in the same in-memory
38  * log page during the pageout of previous/current log page(s) are
39  * committed together by the pageout of the page.
40  *
41  *	TBD lazy commit:
42  * transactions are committed asynchronously when the log page
43  * containing it COMMIT is paged out when it becomes full;
44  *
45  *	serialization:
46  * . a per log lock serialize log write.
47  * . a per log lock serialize group commit.
48  * . a per log lock serialize log open/close;
49  *
50  *	TBD log integrity:
51  * careful-write (ping-pong) of last logpage to recover from crash
52  * in overwrite.
53  * detection of split (out-of-order) write of physical sectors
54  * of last logpage via timestamp at end of each sector
55  * with its mirror data array at trailer).
56  *
57  *	alternatives:
58  * lsn - 64-bit monotonically increasing integer vs
59  * 32-bit lspn and page eor.
60  */
61 
62 #include <linux/fs.h>
63 #include <linux/blkdev.h>
64 #include <linux/interrupt.h>
65 #include <linux/completion.h>
66 #include <linux/kthread.h>
67 #include <linux/buffer_head.h>		/* for sync_blockdev() */
68 #include <linux/bio.h>
69 #include <linux/freezer.h>
70 #include <linux/delay.h>
71 #include <linux/mutex.h>
72 #include <linux/seq_file.h>
73 #include <linux/slab.h>
74 #include "jfs_incore.h"
75 #include "jfs_filsys.h"
76 #include "jfs_metapage.h"
77 #include "jfs_superblock.h"
78 #include "jfs_txnmgr.h"
79 #include "jfs_debug.h"
80 
81 
82 /*
83  * lbuf's ready to be redriven.  Protected by log_redrive_lock (jfsIO thread)
84  */
85 static struct lbuf *log_redrive_list;
86 static DEFINE_SPINLOCK(log_redrive_lock);
87 
88 
89 /*
90  *	log read/write serialization (per log)
91  */
92 #define LOG_LOCK_INIT(log)	mutex_init(&(log)->loglock)
93 #define LOG_LOCK(log)		mutex_lock(&((log)->loglock))
94 #define LOG_UNLOCK(log)		mutex_unlock(&((log)->loglock))
95 
96 
97 /*
98  *	log group commit serialization (per log)
99  */
100 
101 #define LOGGC_LOCK_INIT(log)	spin_lock_init(&(log)->gclock)
102 #define LOGGC_LOCK(log)		spin_lock_irq(&(log)->gclock)
103 #define LOGGC_UNLOCK(log)	spin_unlock_irq(&(log)->gclock)
104 #define LOGGC_WAKEUP(tblk)	wake_up_all(&(tblk)->gcwait)
105 
106 /*
107  *	log sync serialization (per log)
108  */
109 #define	LOGSYNC_DELTA(logsize)		min((logsize)/8, 128*LOGPSIZE)
110 #define	LOGSYNC_BARRIER(logsize)	((logsize)/4)
111 /*
112 #define	LOGSYNC_DELTA(logsize)		min((logsize)/4, 256*LOGPSIZE)
113 #define	LOGSYNC_BARRIER(logsize)	((logsize)/2)
114 */
115 
116 
117 /*
118  *	log buffer cache synchronization
119  */
120 static DEFINE_SPINLOCK(jfsLCacheLock);
121 
122 #define	LCACHE_LOCK(flags)	spin_lock_irqsave(&jfsLCacheLock, flags)
123 #define	LCACHE_UNLOCK(flags)	spin_unlock_irqrestore(&jfsLCacheLock, flags)
124 
125 /*
126  * See __SLEEP_COND in jfs_locks.h
127  */
128 #define LCACHE_SLEEP_COND(wq, cond, flags)	\
129 do {						\
130 	if (cond)				\
131 		break;				\
132 	__SLEEP_COND(wq, cond, LCACHE_LOCK(flags), LCACHE_UNLOCK(flags)); \
133 } while (0)
134 
135 #define	LCACHE_WAKEUP(event)	wake_up(event)
136 
137 
138 /*
139  *	lbuf buffer cache (lCache) control
140  */
141 /* log buffer manager pageout control (cumulative, inclusive) */
142 #define	lbmREAD		0x0001
143 #define	lbmWRITE	0x0002	/* enqueue at tail of write queue;
144 				 * init pageout if at head of queue;
145 				 */
146 #define	lbmRELEASE	0x0004	/* remove from write queue
147 				 * at completion of pageout;
148 				 * do not free/recycle it yet:
149 				 * caller will free it;
150 				 */
151 #define	lbmSYNC		0x0008	/* do not return to freelist
152 				 * when removed from write queue;
153 				 */
154 #define lbmFREE		0x0010	/* return to freelist
155 				 * at completion of pageout;
156 				 * the buffer may be recycled;
157 				 */
158 #define	lbmDONE		0x0020
159 #define	lbmERROR	0x0040
160 #define lbmGC		0x0080	/* lbmIODone to perform post-GC processing
161 				 * of log page
162 				 */
163 #define lbmDIRECT	0x0100
164 
165 /*
166  * Global list of active external journals
167  */
168 static LIST_HEAD(jfs_external_logs);
169 static struct jfs_log *dummy_log = NULL;
170 static DEFINE_MUTEX(jfs_log_mutex);
171 
172 /*
173  * forward references
174  */
175 static int lmWriteRecord(struct jfs_log * log, struct tblock * tblk,
176 			 struct lrd * lrd, struct tlock * tlck);
177 
178 static int lmNextPage(struct jfs_log * log);
179 static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
180 			   int activate);
181 
182 static int open_inline_log(struct super_block *sb);
183 static int open_dummy_log(struct super_block *sb);
184 static int lbmLogInit(struct jfs_log * log);
185 static void lbmLogShutdown(struct jfs_log * log);
186 static struct lbuf *lbmAllocate(struct jfs_log * log, int);
187 static void lbmFree(struct lbuf * bp);
188 static void lbmfree(struct lbuf * bp);
189 static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp);
190 static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag, int cant_block);
191 static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag);
192 static int lbmIOWait(struct lbuf * bp, int flag);
193 static bio_end_io_t lbmIODone;
194 static void lbmStartIO(struct lbuf * bp);
195 static void lmGCwrite(struct jfs_log * log, int cant_block);
196 static int lmLogSync(struct jfs_log * log, int hard_sync);
197 
198 
199 
200 /*
201  *	statistics
202  */
203 #ifdef CONFIG_JFS_STATISTICS
204 static struct lmStat {
205 	uint commit;		/* # of commit */
206 	uint pagedone;		/* # of page written */
207 	uint submitted;		/* # of pages submitted */
208 	uint full_page;		/* # of full pages submitted */
209 	uint partial_page;	/* # of partial pages submitted */
210 } lmStat;
211 #endif
212 
write_special_inodes(struct jfs_log * log,int (* writer)(struct address_space *))213 static void write_special_inodes(struct jfs_log *log,
214 				 int (*writer)(struct address_space *))
215 {
216 	struct jfs_sb_info *sbi;
217 
218 	list_for_each_entry(sbi, &log->sb_list, log_list) {
219 		writer(sbi->ipbmap->i_mapping);
220 		writer(sbi->ipimap->i_mapping);
221 		writer(sbi->direct_inode->i_mapping);
222 	}
223 }
224 
225 /*
226  * NAME:	lmLog()
227  *
228  * FUNCTION:	write a log record;
229  *
230  * PARAMETER:
231  *
232  * RETURN:	lsn - offset to the next log record to write (end-of-log);
233  *		-1  - error;
234  *
235  * note: todo: log error handler
236  */
lmLog(struct jfs_log * log,struct tblock * tblk,struct lrd * lrd,struct tlock * tlck)237 int lmLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
238 	  struct tlock * tlck)
239 {
240 	int lsn;
241 	int diffp, difft;
242 	struct metapage *mp = NULL;
243 	unsigned long flags;
244 
245 	jfs_info("lmLog: log:0x%p tblk:0x%p, lrd:0x%p tlck:0x%p",
246 		 log, tblk, lrd, tlck);
247 
248 	LOG_LOCK(log);
249 
250 	/* log by (out-of-transaction) JFS ? */
251 	if (tblk == NULL)
252 		goto writeRecord;
253 
254 	/* log from page ? */
255 	if (tlck == NULL ||
256 	    tlck->type & tlckBTROOT || (mp = tlck->mp) == NULL)
257 		goto writeRecord;
258 
259 	/*
260 	 *	initialize/update page/transaction recovery lsn
261 	 */
262 	lsn = log->lsn;
263 
264 	LOGSYNC_LOCK(log, flags);
265 
266 	/*
267 	 * initialize page lsn if first log write of the page
268 	 */
269 	if (mp->lsn == 0) {
270 		mp->log = log;
271 		mp->lsn = lsn;
272 		log->count++;
273 
274 		/* insert page at tail of logsynclist */
275 		list_add_tail(&mp->synclist, &log->synclist);
276 	}
277 
278 	/*
279 	 *	initialize/update lsn of tblock of the page
280 	 *
281 	 * transaction inherits oldest lsn of pages associated
282 	 * with allocation/deallocation of resources (their
283 	 * log records are used to reconstruct allocation map
284 	 * at recovery time: inode for inode allocation map,
285 	 * B+-tree index of extent descriptors for block
286 	 * allocation map);
287 	 * allocation map pages inherit transaction lsn at
288 	 * commit time to allow forwarding log syncpt past log
289 	 * records associated with allocation/deallocation of
290 	 * resources only after persistent map of these map pages
291 	 * have been updated and propagated to home.
292 	 */
293 	/*
294 	 * initialize transaction lsn:
295 	 */
296 	if (tblk->lsn == 0) {
297 		/* inherit lsn of its first page logged */
298 		tblk->lsn = mp->lsn;
299 		log->count++;
300 
301 		/* insert tblock after the page on logsynclist */
302 		list_add(&tblk->synclist, &mp->synclist);
303 	}
304 	/*
305 	 * update transaction lsn:
306 	 */
307 	else {
308 		/* inherit oldest/smallest lsn of page */
309 		logdiff(diffp, mp->lsn, log);
310 		logdiff(difft, tblk->lsn, log);
311 		if (diffp < difft) {
312 			/* update tblock lsn with page lsn */
313 			tblk->lsn = mp->lsn;
314 
315 			/* move tblock after page on logsynclist */
316 			list_move(&tblk->synclist, &mp->synclist);
317 		}
318 	}
319 
320 	LOGSYNC_UNLOCK(log, flags);
321 
322 	/*
323 	 *	write the log record
324 	 */
325       writeRecord:
326 	lsn = lmWriteRecord(log, tblk, lrd, tlck);
327 
328 	/*
329 	 * forward log syncpt if log reached next syncpt trigger
330 	 */
331 	logdiff(diffp, lsn, log);
332 	if (diffp >= log->nextsync)
333 		lsn = lmLogSync(log, 0);
334 
335 	/* update end-of-log lsn */
336 	log->lsn = lsn;
337 
338 	LOG_UNLOCK(log);
339 
340 	/* return end-of-log address */
341 	return lsn;
342 }
343 
344 /*
345  * NAME:	lmWriteRecord()
346  *
347  * FUNCTION:	move the log record to current log page
348  *
349  * PARAMETER:	cd	- commit descriptor
350  *
351  * RETURN:	end-of-log address
352  *
353  * serialization: LOG_LOCK() held on entry/exit
354  */
355 static int
lmWriteRecord(struct jfs_log * log,struct tblock * tblk,struct lrd * lrd,struct tlock * tlck)356 lmWriteRecord(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
357 	      struct tlock * tlck)
358 {
359 	int lsn = 0;		/* end-of-log address */
360 	struct lbuf *bp;	/* dst log page buffer */
361 	struct logpage *lp;	/* dst log page */
362 	caddr_t dst;		/* destination address in log page */
363 	int dstoffset;		/* end-of-log offset in log page */
364 	int freespace;		/* free space in log page */
365 	caddr_t p;		/* src meta-data page */
366 	caddr_t src;
367 	int srclen;
368 	int nbytes;		/* number of bytes to move */
369 	int i;
370 	int len;
371 	struct linelock *linelock;
372 	struct lv *lv;
373 	struct lvd *lvd;
374 	int l2linesize;
375 
376 	len = 0;
377 
378 	/* retrieve destination log page to write */
379 	bp = (struct lbuf *) log->bp;
380 	lp = (struct logpage *) bp->l_ldata;
381 	dstoffset = log->eor;
382 
383 	/* any log data to write ? */
384 	if (tlck == NULL)
385 		goto moveLrd;
386 
387 	/*
388 	 *	move log record data
389 	 */
390 	/* retrieve source meta-data page to log */
391 	if (tlck->flag & tlckPAGELOCK) {
392 		p = (caddr_t) (tlck->mp->data);
393 		linelock = (struct linelock *) & tlck->lock;
394 	}
395 	/* retrieve source in-memory inode to log */
396 	else if (tlck->flag & tlckINODELOCK) {
397 		if (tlck->type & tlckDTREE)
398 			p = (caddr_t) &JFS_IP(tlck->ip)->i_dtroot;
399 		else
400 			p = (caddr_t) &JFS_IP(tlck->ip)->i_xtroot;
401 		linelock = (struct linelock *) & tlck->lock;
402 	}
403 #ifdef	_JFS_WIP
404 	else if (tlck->flag & tlckINLINELOCK) {
405 
406 		inlinelock = (struct inlinelock *) & tlck;
407 		p = (caddr_t) & inlinelock->pxd;
408 		linelock = (struct linelock *) & tlck;
409 	}
410 #endif				/* _JFS_WIP */
411 	else {
412 		jfs_err("lmWriteRecord: UFO tlck:0x%p", tlck);
413 		return 0;	/* Probably should trap */
414 	}
415 	l2linesize = linelock->l2linesize;
416 
417       moveData:
418 	ASSERT(linelock->index <= linelock->maxcnt);
419 
420 	lv = linelock->lv;
421 	for (i = 0; i < linelock->index; i++, lv++) {
422 		if (lv->length == 0)
423 			continue;
424 
425 		/* is page full ? */
426 		if (dstoffset >= LOGPSIZE - LOGPTLRSIZE) {
427 			/* page become full: move on to next page */
428 			lmNextPage(log);
429 
430 			bp = log->bp;
431 			lp = (struct logpage *) bp->l_ldata;
432 			dstoffset = LOGPHDRSIZE;
433 		}
434 
435 		/*
436 		 * move log vector data
437 		 */
438 		src = (u8 *) p + (lv->offset << l2linesize);
439 		srclen = lv->length << l2linesize;
440 		len += srclen;
441 		while (srclen > 0) {
442 			freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
443 			nbytes = min(freespace, srclen);
444 			dst = (caddr_t) lp + dstoffset;
445 			memcpy(dst, src, nbytes);
446 			dstoffset += nbytes;
447 
448 			/* is page not full ? */
449 			if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
450 				break;
451 
452 			/* page become full: move on to next page */
453 			lmNextPage(log);
454 
455 			bp = (struct lbuf *) log->bp;
456 			lp = (struct logpage *) bp->l_ldata;
457 			dstoffset = LOGPHDRSIZE;
458 
459 			srclen -= nbytes;
460 			src += nbytes;
461 		}
462 
463 		/*
464 		 * move log vector descriptor
465 		 */
466 		len += 4;
467 		lvd = (struct lvd *) ((caddr_t) lp + dstoffset);
468 		lvd->offset = cpu_to_le16(lv->offset);
469 		lvd->length = cpu_to_le16(lv->length);
470 		dstoffset += 4;
471 		jfs_info("lmWriteRecord: lv offset:%d length:%d",
472 			 lv->offset, lv->length);
473 	}
474 
475 	if ((i = linelock->next)) {
476 		linelock = (struct linelock *) lid_to_tlock(i);
477 		goto moveData;
478 	}
479 
480 	/*
481 	 *	move log record descriptor
482 	 */
483       moveLrd:
484 	lrd->length = cpu_to_le16(len);
485 
486 	src = (caddr_t) lrd;
487 	srclen = LOGRDSIZE;
488 
489 	while (srclen > 0) {
490 		freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
491 		nbytes = min(freespace, srclen);
492 		dst = (caddr_t) lp + dstoffset;
493 		memcpy(dst, src, nbytes);
494 
495 		dstoffset += nbytes;
496 		srclen -= nbytes;
497 
498 		/* are there more to move than freespace of page ? */
499 		if (srclen)
500 			goto pageFull;
501 
502 		/*
503 		 * end of log record descriptor
504 		 */
505 
506 		/* update last log record eor */
507 		log->eor = dstoffset;
508 		bp->l_eor = dstoffset;
509 		lsn = (log->page << L2LOGPSIZE) + dstoffset;
510 
511 		if (lrd->type & cpu_to_le16(LOG_COMMIT)) {
512 			tblk->clsn = lsn;
513 			jfs_info("wr: tclsn:0x%x, beor:0x%x", tblk->clsn,
514 				 bp->l_eor);
515 
516 			INCREMENT(lmStat.commit);	/* # of commit */
517 
518 			/*
519 			 * enqueue tblock for group commit:
520 			 *
521 			 * enqueue tblock of non-trivial/synchronous COMMIT
522 			 * at tail of group commit queue
523 			 * (trivial/asynchronous COMMITs are ignored by
524 			 * group commit.)
525 			 */
526 			LOGGC_LOCK(log);
527 
528 			/* init tblock gc state */
529 			tblk->flag = tblkGC_QUEUE;
530 			tblk->bp = log->bp;
531 			tblk->pn = log->page;
532 			tblk->eor = log->eor;
533 
534 			/* enqueue transaction to commit queue */
535 			list_add_tail(&tblk->cqueue, &log->cqueue);
536 
537 			LOGGC_UNLOCK(log);
538 		}
539 
540 		jfs_info("lmWriteRecord: lrd:0x%04x bp:0x%p pn:%d eor:0x%x",
541 			le16_to_cpu(lrd->type), log->bp, log->page, dstoffset);
542 
543 		/* page not full ? */
544 		if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
545 			return lsn;
546 
547 	      pageFull:
548 		/* page become full: move on to next page */
549 		lmNextPage(log);
550 
551 		bp = (struct lbuf *) log->bp;
552 		lp = (struct logpage *) bp->l_ldata;
553 		dstoffset = LOGPHDRSIZE;
554 		src += nbytes;
555 	}
556 
557 	return lsn;
558 }
559 
560 
561 /*
562  * NAME:	lmNextPage()
563  *
564  * FUNCTION:	write current page and allocate next page.
565  *
566  * PARAMETER:	log
567  *
568  * RETURN:	0
569  *
570  * serialization: LOG_LOCK() held on entry/exit
571  */
lmNextPage(struct jfs_log * log)572 static int lmNextPage(struct jfs_log * log)
573 {
574 	struct logpage *lp;
575 	int lspn;		/* log sequence page number */
576 	int pn;			/* current page number */
577 	struct lbuf *bp;
578 	struct lbuf *nextbp;
579 	struct tblock *tblk;
580 
581 	/* get current log page number and log sequence page number */
582 	pn = log->page;
583 	bp = log->bp;
584 	lp = (struct logpage *) bp->l_ldata;
585 	lspn = le32_to_cpu(lp->h.page);
586 
587 	LOGGC_LOCK(log);
588 
589 	/*
590 	 *	write or queue the full page at the tail of write queue
591 	 */
592 	/* get the tail tblk on commit queue */
593 	if (list_empty(&log->cqueue))
594 		tblk = NULL;
595 	else
596 		tblk = list_entry(log->cqueue.prev, struct tblock, cqueue);
597 
598 	/* every tblk who has COMMIT record on the current page,
599 	 * and has not been committed, must be on commit queue
600 	 * since tblk is queued at commit queueu at the time
601 	 * of writing its COMMIT record on the page before
602 	 * page becomes full (even though the tblk thread
603 	 * who wrote COMMIT record may have been suspended
604 	 * currently);
605 	 */
606 
607 	/* is page bound with outstanding tail tblk ? */
608 	if (tblk && tblk->pn == pn) {
609 		/* mark tblk for end-of-page */
610 		tblk->flag |= tblkGC_EOP;
611 
612 		if (log->cflag & logGC_PAGEOUT) {
613 			/* if page is not already on write queue,
614 			 * just enqueue (no lbmWRITE to prevent redrive)
615 			 * buffer to wqueue to ensure correct serial order
616 			 * of the pages since log pages will be added
617 			 * continuously
618 			 */
619 			if (bp->l_wqnext == NULL)
620 				lbmWrite(log, bp, 0, 0);
621 		} else {
622 			/*
623 			 * No current GC leader, initiate group commit
624 			 */
625 			log->cflag |= logGC_PAGEOUT;
626 			lmGCwrite(log, 0);
627 		}
628 	}
629 	/* page is not bound with outstanding tblk:
630 	 * init write or mark it to be redriven (lbmWRITE)
631 	 */
632 	else {
633 		/* finalize the page */
634 		bp->l_ceor = bp->l_eor;
635 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
636 		lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE, 0);
637 	}
638 	LOGGC_UNLOCK(log);
639 
640 	/*
641 	 *	allocate/initialize next page
642 	 */
643 	/* if log wraps, the first data page of log is 2
644 	 * (0 never used, 1 is superblock).
645 	 */
646 	log->page = (pn == log->size - 1) ? 2 : pn + 1;
647 	log->eor = LOGPHDRSIZE;	/* ? valid page empty/full at logRedo() */
648 
649 	/* allocate/initialize next log page buffer */
650 	nextbp = lbmAllocate(log, log->page);
651 	nextbp->l_eor = log->eor;
652 	log->bp = nextbp;
653 
654 	/* initialize next log page */
655 	lp = (struct logpage *) nextbp->l_ldata;
656 	lp->h.page = lp->t.page = cpu_to_le32(lspn + 1);
657 	lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
658 
659 	return 0;
660 }
661 
662 
663 /*
664  * NAME:	lmGroupCommit()
665  *
666  * FUNCTION:	group commit
667  *	initiate pageout of the pages with COMMIT in the order of
668  *	page number - redrive pageout of the page at the head of
669  *	pageout queue until full page has been written.
670  *
671  * RETURN:
672  *
673  * NOTE:
674  *	LOGGC_LOCK serializes log group commit queue, and
675  *	transaction blocks on the commit queue.
676  *	N.B. LOG_LOCK is NOT held during lmGroupCommit().
677  */
lmGroupCommit(struct jfs_log * log,struct tblock * tblk)678 int lmGroupCommit(struct jfs_log * log, struct tblock * tblk)
679 {
680 	int rc = 0;
681 
682 	LOGGC_LOCK(log);
683 
684 	/* group committed already ? */
685 	if (tblk->flag & tblkGC_COMMITTED) {
686 		if (tblk->flag & tblkGC_ERROR)
687 			rc = -EIO;
688 
689 		LOGGC_UNLOCK(log);
690 		return rc;
691 	}
692 	jfs_info("lmGroup Commit: tblk = 0x%p, gcrtc = %d", tblk, log->gcrtc);
693 
694 	if (tblk->xflag & COMMIT_LAZY)
695 		tblk->flag |= tblkGC_LAZY;
696 
697 	if ((!(log->cflag & logGC_PAGEOUT)) && (!list_empty(&log->cqueue)) &&
698 	    (!(tblk->xflag & COMMIT_LAZY) || test_bit(log_FLUSH, &log->flag)
699 	     || jfs_tlocks_low)) {
700 		/*
701 		 * No pageout in progress
702 		 *
703 		 * start group commit as its group leader.
704 		 */
705 		log->cflag |= logGC_PAGEOUT;
706 
707 		lmGCwrite(log, 0);
708 	}
709 
710 	if (tblk->xflag & COMMIT_LAZY) {
711 		/*
712 		 * Lazy transactions can leave now
713 		 */
714 		LOGGC_UNLOCK(log);
715 		return 0;
716 	}
717 
718 	/* lmGCwrite gives up LOGGC_LOCK, check again */
719 
720 	if (tblk->flag & tblkGC_COMMITTED) {
721 		if (tblk->flag & tblkGC_ERROR)
722 			rc = -EIO;
723 
724 		LOGGC_UNLOCK(log);
725 		return rc;
726 	}
727 
728 	/* upcount transaction waiting for completion
729 	 */
730 	log->gcrtc++;
731 	tblk->flag |= tblkGC_READY;
732 
733 	__SLEEP_COND(tblk->gcwait, (tblk->flag & tblkGC_COMMITTED),
734 		     LOGGC_LOCK(log), LOGGC_UNLOCK(log));
735 
736 	/* removed from commit queue */
737 	if (tblk->flag & tblkGC_ERROR)
738 		rc = -EIO;
739 
740 	LOGGC_UNLOCK(log);
741 	return rc;
742 }
743 
744 /*
745  * NAME:	lmGCwrite()
746  *
747  * FUNCTION:	group commit write
748  *	initiate write of log page, building a group of all transactions
749  *	with commit records on that page.
750  *
751  * RETURN:	None
752  *
753  * NOTE:
754  *	LOGGC_LOCK must be held by caller.
755  *	N.B. LOG_LOCK is NOT held during lmGroupCommit().
756  */
lmGCwrite(struct jfs_log * log,int cant_write)757 static void lmGCwrite(struct jfs_log * log, int cant_write)
758 {
759 	struct lbuf *bp;
760 	struct logpage *lp;
761 	int gcpn;		/* group commit page number */
762 	struct tblock *tblk;
763 	struct tblock *xtblk = NULL;
764 
765 	/*
766 	 * build the commit group of a log page
767 	 *
768 	 * scan commit queue and make a commit group of all
769 	 * transactions with COMMIT records on the same log page.
770 	 */
771 	/* get the head tblk on the commit queue */
772 	gcpn = list_entry(log->cqueue.next, struct tblock, cqueue)->pn;
773 
774 	list_for_each_entry(tblk, &log->cqueue, cqueue) {
775 		if (tblk->pn != gcpn)
776 			break;
777 
778 		xtblk = tblk;
779 
780 		/* state transition: (QUEUE, READY) -> COMMIT */
781 		tblk->flag |= tblkGC_COMMIT;
782 	}
783 	tblk = xtblk;		/* last tblk of the page */
784 
785 	/*
786 	 * pageout to commit transactions on the log page.
787 	 */
788 	bp = (struct lbuf *) tblk->bp;
789 	lp = (struct logpage *) bp->l_ldata;
790 	/* is page already full ? */
791 	if (tblk->flag & tblkGC_EOP) {
792 		/* mark page to free at end of group commit of the page */
793 		tblk->flag &= ~tblkGC_EOP;
794 		tblk->flag |= tblkGC_FREE;
795 		bp->l_ceor = bp->l_eor;
796 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
797 		lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmGC,
798 			 cant_write);
799 		INCREMENT(lmStat.full_page);
800 	}
801 	/* page is not yet full */
802 	else {
803 		bp->l_ceor = tblk->eor;	/* ? bp->l_ceor = bp->l_eor; */
804 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
805 		lbmWrite(log, bp, lbmWRITE | lbmGC, cant_write);
806 		INCREMENT(lmStat.partial_page);
807 	}
808 }
809 
810 /*
811  * NAME:	lmPostGC()
812  *
813  * FUNCTION:	group commit post-processing
814  *	Processes transactions after their commit records have been written
815  *	to disk, redriving log I/O if necessary.
816  *
817  * RETURN:	None
818  *
819  * NOTE:
820  *	This routine is called a interrupt time by lbmIODone
821  */
lmPostGC(struct lbuf * bp)822 static void lmPostGC(struct lbuf * bp)
823 {
824 	unsigned long flags;
825 	struct jfs_log *log = bp->l_log;
826 	struct logpage *lp;
827 	struct tblock *tblk, *temp;
828 
829 	//LOGGC_LOCK(log);
830 	spin_lock_irqsave(&log->gclock, flags);
831 	/*
832 	 * current pageout of group commit completed.
833 	 *
834 	 * remove/wakeup transactions from commit queue who were
835 	 * group committed with the current log page
836 	 */
837 	list_for_each_entry_safe(tblk, temp, &log->cqueue, cqueue) {
838 		if (!(tblk->flag & tblkGC_COMMIT))
839 			break;
840 		/* if transaction was marked GC_COMMIT then
841 		 * it has been shipped in the current pageout
842 		 * and made it to disk - it is committed.
843 		 */
844 
845 		if (bp->l_flag & lbmERROR)
846 			tblk->flag |= tblkGC_ERROR;
847 
848 		/* remove it from the commit queue */
849 		list_del(&tblk->cqueue);
850 		tblk->flag &= ~tblkGC_QUEUE;
851 
852 		if (tblk == log->flush_tblk) {
853 			/* we can stop flushing the log now */
854 			clear_bit(log_FLUSH, &log->flag);
855 			log->flush_tblk = NULL;
856 		}
857 
858 		jfs_info("lmPostGC: tblk = 0x%p, flag = 0x%x", tblk,
859 			 tblk->flag);
860 
861 		if (!(tblk->xflag & COMMIT_FORCE))
862 			/*
863 			 * Hand tblk over to lazy commit thread
864 			 */
865 			txLazyUnlock(tblk);
866 		else {
867 			/* state transition: COMMIT -> COMMITTED */
868 			tblk->flag |= tblkGC_COMMITTED;
869 
870 			if (tblk->flag & tblkGC_READY)
871 				log->gcrtc--;
872 
873 			LOGGC_WAKEUP(tblk);
874 		}
875 
876 		/* was page full before pageout ?
877 		 * (and this is the last tblk bound with the page)
878 		 */
879 		if (tblk->flag & tblkGC_FREE)
880 			lbmFree(bp);
881 		/* did page become full after pageout ?
882 		 * (and this is the last tblk bound with the page)
883 		 */
884 		else if (tblk->flag & tblkGC_EOP) {
885 			/* finalize the page */
886 			lp = (struct logpage *) bp->l_ldata;
887 			bp->l_ceor = bp->l_eor;
888 			lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
889 			jfs_info("lmPostGC: calling lbmWrite");
890 			lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE,
891 				 1);
892 		}
893 
894 	}
895 
896 	/* are there any transactions who have entered lnGroupCommit()
897 	 * (whose COMMITs are after that of the last log page written.
898 	 * They are waiting for new group commit (above at (SLEEP 1))
899 	 * or lazy transactions are on a full (queued) log page,
900 	 * select the latest ready transaction as new group leader and
901 	 * wake her up to lead her group.
902 	 */
903 	if ((!list_empty(&log->cqueue)) &&
904 	    ((log->gcrtc > 0) || (tblk->bp->l_wqnext != NULL) ||
905 	     test_bit(log_FLUSH, &log->flag) || jfs_tlocks_low))
906 		/*
907 		 * Call lmGCwrite with new group leader
908 		 */
909 		lmGCwrite(log, 1);
910 
911 	/* no transaction are ready yet (transactions are only just
912 	 * queued (GC_QUEUE) and not entered for group commit yet).
913 	 * the first transaction entering group commit
914 	 * will elect herself as new group leader.
915 	 */
916 	else
917 		log->cflag &= ~logGC_PAGEOUT;
918 
919 	//LOGGC_UNLOCK(log);
920 	spin_unlock_irqrestore(&log->gclock, flags);
921 	return;
922 }
923 
924 /*
925  * NAME:	lmLogSync()
926  *
927  * FUNCTION:	write log SYNCPT record for specified log
928  *	if new sync address is available
929  *	(normally the case if sync() is executed by back-ground
930  *	process).
931  *	calculate new value of i_nextsync which determines when
932  *	this code is called again.
933  *
934  * PARAMETERS:	log	- log structure
935  *		hard_sync - 1 to force all metadata to be written
936  *
937  * RETURN:	0
938  *
939  * serialization: LOG_LOCK() held on entry/exit
940  */
lmLogSync(struct jfs_log * log,int hard_sync)941 static int lmLogSync(struct jfs_log * log, int hard_sync)
942 {
943 	int logsize;
944 	int written;		/* written since last syncpt */
945 	int free;		/* free space left available */
946 	int delta;		/* additional delta to write normally */
947 	int more;		/* additional write granted */
948 	struct lrd lrd;
949 	int lsn;
950 	struct logsyncblk *lp;
951 	unsigned long flags;
952 
953 	/* push dirty metapages out to disk */
954 	if (hard_sync)
955 		write_special_inodes(log, filemap_fdatawrite);
956 	else
957 		write_special_inodes(log, filemap_flush);
958 
959 	/*
960 	 *	forward syncpt
961 	 */
962 	/* if last sync is same as last syncpt,
963 	 * invoke sync point forward processing to update sync.
964 	 */
965 
966 	if (log->sync == log->syncpt) {
967 		LOGSYNC_LOCK(log, flags);
968 		if (list_empty(&log->synclist))
969 			log->sync = log->lsn;
970 		else {
971 			lp = list_entry(log->synclist.next,
972 					struct logsyncblk, synclist);
973 			log->sync = lp->lsn;
974 		}
975 		LOGSYNC_UNLOCK(log, flags);
976 
977 	}
978 
979 	/* if sync is different from last syncpt,
980 	 * write a SYNCPT record with syncpt = sync.
981 	 * reset syncpt = sync
982 	 */
983 	if (log->sync != log->syncpt) {
984 		lrd.logtid = 0;
985 		lrd.backchain = 0;
986 		lrd.type = cpu_to_le16(LOG_SYNCPT);
987 		lrd.length = 0;
988 		lrd.log.syncpt.sync = cpu_to_le32(log->sync);
989 		lsn = lmWriteRecord(log, NULL, &lrd, NULL);
990 
991 		log->syncpt = log->sync;
992 	} else
993 		lsn = log->lsn;
994 
995 	/*
996 	 *	setup next syncpt trigger (SWAG)
997 	 */
998 	logsize = log->logsize;
999 
1000 	logdiff(written, lsn, log);
1001 	free = logsize - written;
1002 	delta = LOGSYNC_DELTA(logsize);
1003 	more = min(free / 2, delta);
1004 	if (more < 2 * LOGPSIZE) {
1005 		jfs_warn("\n ... Log Wrap ... Log Wrap ... Log Wrap ...\n");
1006 		/*
1007 		 *	log wrapping
1008 		 *
1009 		 * option 1 - panic ? No.!
1010 		 * option 2 - shutdown file systems
1011 		 *	      associated with log ?
1012 		 * option 3 - extend log ?
1013 		 * option 4 - second chance
1014 		 *
1015 		 * mark log wrapped, and continue.
1016 		 * when all active transactions are completed,
1017 		 * mark log valid for recovery.
1018 		 * if crashed during invalid state, log state
1019 		 * implies invalid log, forcing fsck().
1020 		 */
1021 		/* mark log state log wrap in log superblock */
1022 		/* log->state = LOGWRAP; */
1023 
1024 		/* reset sync point computation */
1025 		log->syncpt = log->sync = lsn;
1026 		log->nextsync = delta;
1027 	} else
1028 		/* next syncpt trigger = written + more */
1029 		log->nextsync = written + more;
1030 
1031 	/* if number of bytes written from last sync point is more
1032 	 * than 1/4 of the log size, stop new transactions from
1033 	 * starting until all current transactions are completed
1034 	 * by setting syncbarrier flag.
1035 	 */
1036 	if (!test_bit(log_SYNCBARRIER, &log->flag) &&
1037 	    (written > LOGSYNC_BARRIER(logsize)) && log->active) {
1038 		set_bit(log_SYNCBARRIER, &log->flag);
1039 		jfs_info("log barrier on: lsn=0x%x syncpt=0x%x", lsn,
1040 			 log->syncpt);
1041 		/*
1042 		 * We may have to initiate group commit
1043 		 */
1044 		jfs_flush_journal(log, 0);
1045 	}
1046 
1047 	return lsn;
1048 }
1049 
1050 /*
1051  * NAME:	jfs_syncpt
1052  *
1053  * FUNCTION:	write log SYNCPT record for specified log
1054  *
1055  * PARAMETERS:	log	  - log structure
1056  *		hard_sync - set to 1 to force metadata to be written
1057  */
jfs_syncpt(struct jfs_log * log,int hard_sync)1058 void jfs_syncpt(struct jfs_log *log, int hard_sync)
1059 {	LOG_LOCK(log);
1060 	lmLogSync(log, hard_sync);
1061 	LOG_UNLOCK(log);
1062 }
1063 
1064 /*
1065  * NAME:	lmLogOpen()
1066  *
1067  * FUNCTION:	open the log on first open;
1068  *	insert filesystem in the active list of the log.
1069  *
1070  * PARAMETER:	ipmnt	- file system mount inode
1071  *		iplog	- log inode (out)
1072  *
1073  * RETURN:
1074  *
1075  * serialization:
1076  */
lmLogOpen(struct super_block * sb)1077 int lmLogOpen(struct super_block *sb)
1078 {
1079 	int rc;
1080 	struct block_device *bdev;
1081 	struct jfs_log *log;
1082 	struct jfs_sb_info *sbi = JFS_SBI(sb);
1083 
1084 	if (sbi->flag & JFS_NOINTEGRITY)
1085 		return open_dummy_log(sb);
1086 
1087 	if (sbi->mntflag & JFS_INLINELOG)
1088 		return open_inline_log(sb);
1089 
1090 	mutex_lock(&jfs_log_mutex);
1091 	list_for_each_entry(log, &jfs_external_logs, journal_list) {
1092 		if (log->bdev->bd_dev == sbi->logdev) {
1093 			if (memcmp(log->uuid, sbi->loguuid,
1094 				   sizeof(log->uuid))) {
1095 				jfs_warn("wrong uuid on JFS journal\n");
1096 				mutex_unlock(&jfs_log_mutex);
1097 				return -EINVAL;
1098 			}
1099 			/*
1100 			 * add file system to log active file system list
1101 			 */
1102 			if ((rc = lmLogFileSystem(log, sbi, 1))) {
1103 				mutex_unlock(&jfs_log_mutex);
1104 				return rc;
1105 			}
1106 			goto journal_found;
1107 		}
1108 	}
1109 
1110 	if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL))) {
1111 		mutex_unlock(&jfs_log_mutex);
1112 		return -ENOMEM;
1113 	}
1114 	INIT_LIST_HEAD(&log->sb_list);
1115 	init_waitqueue_head(&log->syncwait);
1116 
1117 	/*
1118 	 *	external log as separate logical volume
1119 	 *
1120 	 * file systems to log may have n-to-1 relationship;
1121 	 */
1122 
1123 	bdev = blkdev_get_by_dev(sbi->logdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
1124 				 log);
1125 	if (IS_ERR(bdev)) {
1126 		rc = -PTR_ERR(bdev);
1127 		goto free;
1128 	}
1129 
1130 	log->bdev = bdev;
1131 	memcpy(log->uuid, sbi->loguuid, sizeof(log->uuid));
1132 
1133 	/*
1134 	 * initialize log:
1135 	 */
1136 	if ((rc = lmLogInit(log)))
1137 		goto close;
1138 
1139 	list_add(&log->journal_list, &jfs_external_logs);
1140 
1141 	/*
1142 	 * add file system to log active file system list
1143 	 */
1144 	if ((rc = lmLogFileSystem(log, sbi, 1)))
1145 		goto shutdown;
1146 
1147 journal_found:
1148 	LOG_LOCK(log);
1149 	list_add(&sbi->log_list, &log->sb_list);
1150 	sbi->log = log;
1151 	LOG_UNLOCK(log);
1152 
1153 	mutex_unlock(&jfs_log_mutex);
1154 	return 0;
1155 
1156 	/*
1157 	 *	unwind on error
1158 	 */
1159       shutdown:		/* unwind lbmLogInit() */
1160 	list_del(&log->journal_list);
1161 	lbmLogShutdown(log);
1162 
1163       close:		/* close external log device */
1164 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1165 
1166       free:		/* free log descriptor */
1167 	mutex_unlock(&jfs_log_mutex);
1168 	kfree(log);
1169 
1170 	jfs_warn("lmLogOpen: exit(%d)", rc);
1171 	return rc;
1172 }
1173 
open_inline_log(struct super_block * sb)1174 static int open_inline_log(struct super_block *sb)
1175 {
1176 	struct jfs_log *log;
1177 	int rc;
1178 
1179 	if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL)))
1180 		return -ENOMEM;
1181 	INIT_LIST_HEAD(&log->sb_list);
1182 	init_waitqueue_head(&log->syncwait);
1183 
1184 	set_bit(log_INLINELOG, &log->flag);
1185 	log->bdev = sb->s_bdev;
1186 	log->base = addressPXD(&JFS_SBI(sb)->logpxd);
1187 	log->size = lengthPXD(&JFS_SBI(sb)->logpxd) >>
1188 	    (L2LOGPSIZE - sb->s_blocksize_bits);
1189 	log->l2bsize = sb->s_blocksize_bits;
1190 	ASSERT(L2LOGPSIZE >= sb->s_blocksize_bits);
1191 
1192 	/*
1193 	 * initialize log.
1194 	 */
1195 	if ((rc = lmLogInit(log))) {
1196 		kfree(log);
1197 		jfs_warn("lmLogOpen: exit(%d)", rc);
1198 		return rc;
1199 	}
1200 
1201 	list_add(&JFS_SBI(sb)->log_list, &log->sb_list);
1202 	JFS_SBI(sb)->log = log;
1203 
1204 	return rc;
1205 }
1206 
open_dummy_log(struct super_block * sb)1207 static int open_dummy_log(struct super_block *sb)
1208 {
1209 	int rc;
1210 
1211 	mutex_lock(&jfs_log_mutex);
1212 	if (!dummy_log) {
1213 		dummy_log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL);
1214 		if (!dummy_log) {
1215 			mutex_unlock(&jfs_log_mutex);
1216 			return -ENOMEM;
1217 		}
1218 		INIT_LIST_HEAD(&dummy_log->sb_list);
1219 		init_waitqueue_head(&dummy_log->syncwait);
1220 		dummy_log->no_integrity = 1;
1221 		/* Make up some stuff */
1222 		dummy_log->base = 0;
1223 		dummy_log->size = 1024;
1224 		rc = lmLogInit(dummy_log);
1225 		if (rc) {
1226 			kfree(dummy_log);
1227 			dummy_log = NULL;
1228 			mutex_unlock(&jfs_log_mutex);
1229 			return rc;
1230 		}
1231 	}
1232 
1233 	LOG_LOCK(dummy_log);
1234 	list_add(&JFS_SBI(sb)->log_list, &dummy_log->sb_list);
1235 	JFS_SBI(sb)->log = dummy_log;
1236 	LOG_UNLOCK(dummy_log);
1237 	mutex_unlock(&jfs_log_mutex);
1238 
1239 	return 0;
1240 }
1241 
1242 /*
1243  * NAME:	lmLogInit()
1244  *
1245  * FUNCTION:	log initialization at first log open.
1246  *
1247  *	logredo() (or logformat()) should have been run previously.
1248  *	initialize the log from log superblock.
1249  *	set the log state in the superblock to LOGMOUNT and
1250  *	write SYNCPT log record.
1251  *
1252  * PARAMETER:	log	- log structure
1253  *
1254  * RETURN:	0	- if ok
1255  *		-EINVAL	- bad log magic number or superblock dirty
1256  *		error returned from logwait()
1257  *
1258  * serialization: single first open thread
1259  */
lmLogInit(struct jfs_log * log)1260 int lmLogInit(struct jfs_log * log)
1261 {
1262 	int rc = 0;
1263 	struct lrd lrd;
1264 	struct logsuper *logsuper;
1265 	struct lbuf *bpsuper;
1266 	struct lbuf *bp;
1267 	struct logpage *lp;
1268 	int lsn = 0;
1269 
1270 	jfs_info("lmLogInit: log:0x%p", log);
1271 
1272 	/* initialize the group commit serialization lock */
1273 	LOGGC_LOCK_INIT(log);
1274 
1275 	/* allocate/initialize the log write serialization lock */
1276 	LOG_LOCK_INIT(log);
1277 
1278 	LOGSYNC_LOCK_INIT(log);
1279 
1280 	INIT_LIST_HEAD(&log->synclist);
1281 
1282 	INIT_LIST_HEAD(&log->cqueue);
1283 	log->flush_tblk = NULL;
1284 
1285 	log->count = 0;
1286 
1287 	/*
1288 	 * initialize log i/o
1289 	 */
1290 	if ((rc = lbmLogInit(log)))
1291 		return rc;
1292 
1293 	if (!test_bit(log_INLINELOG, &log->flag))
1294 		log->l2bsize = L2LOGPSIZE;
1295 
1296 	/* check for disabled journaling to disk */
1297 	if (log->no_integrity) {
1298 		/*
1299 		 * Journal pages will still be filled.  When the time comes
1300 		 * to actually do the I/O, the write is not done, and the
1301 		 * endio routine is called directly.
1302 		 */
1303 		bp = lbmAllocate(log , 0);
1304 		log->bp = bp;
1305 		bp->l_pn = bp->l_eor = 0;
1306 	} else {
1307 		/*
1308 		 * validate log superblock
1309 		 */
1310 		if ((rc = lbmRead(log, 1, &bpsuper)))
1311 			goto errout10;
1312 
1313 		logsuper = (struct logsuper *) bpsuper->l_ldata;
1314 
1315 		if (logsuper->magic != cpu_to_le32(LOGMAGIC)) {
1316 			jfs_warn("*** Log Format Error ! ***");
1317 			rc = -EINVAL;
1318 			goto errout20;
1319 		}
1320 
1321 		/* logredo() should have been run successfully. */
1322 		if (logsuper->state != cpu_to_le32(LOGREDONE)) {
1323 			jfs_warn("*** Log Is Dirty ! ***");
1324 			rc = -EINVAL;
1325 			goto errout20;
1326 		}
1327 
1328 		/* initialize log from log superblock */
1329 		if (test_bit(log_INLINELOG,&log->flag)) {
1330 			if (log->size != le32_to_cpu(logsuper->size)) {
1331 				rc = -EINVAL;
1332 				goto errout20;
1333 			}
1334 			jfs_info("lmLogInit: inline log:0x%p base:0x%Lx "
1335 				 "size:0x%x", log,
1336 				 (unsigned long long) log->base, log->size);
1337 		} else {
1338 			if (memcmp(logsuper->uuid, log->uuid, 16)) {
1339 				jfs_warn("wrong uuid on JFS log device");
1340 				goto errout20;
1341 			}
1342 			log->size = le32_to_cpu(logsuper->size);
1343 			log->l2bsize = le32_to_cpu(logsuper->l2bsize);
1344 			jfs_info("lmLogInit: external log:0x%p base:0x%Lx "
1345 				 "size:0x%x", log,
1346 				 (unsigned long long) log->base, log->size);
1347 		}
1348 
1349 		log->page = le32_to_cpu(logsuper->end) / LOGPSIZE;
1350 		log->eor = le32_to_cpu(logsuper->end) - (LOGPSIZE * log->page);
1351 
1352 		/*
1353 		 * initialize for log append write mode
1354 		 */
1355 		/* establish current/end-of-log page/buffer */
1356 		if ((rc = lbmRead(log, log->page, &bp)))
1357 			goto errout20;
1358 
1359 		lp = (struct logpage *) bp->l_ldata;
1360 
1361 		jfs_info("lmLogInit: lsn:0x%x page:%d eor:%d:%d",
1362 			 le32_to_cpu(logsuper->end), log->page, log->eor,
1363 			 le16_to_cpu(lp->h.eor));
1364 
1365 		log->bp = bp;
1366 		bp->l_pn = log->page;
1367 		bp->l_eor = log->eor;
1368 
1369 		/* if current page is full, move on to next page */
1370 		if (log->eor >= LOGPSIZE - LOGPTLRSIZE)
1371 			lmNextPage(log);
1372 
1373 		/*
1374 		 * initialize log syncpoint
1375 		 */
1376 		/*
1377 		 * write the first SYNCPT record with syncpoint = 0
1378 		 * (i.e., log redo up to HERE !);
1379 		 * remove current page from lbm write queue at end of pageout
1380 		 * (to write log superblock update), but do not release to
1381 		 * freelist;
1382 		 */
1383 		lrd.logtid = 0;
1384 		lrd.backchain = 0;
1385 		lrd.type = cpu_to_le16(LOG_SYNCPT);
1386 		lrd.length = 0;
1387 		lrd.log.syncpt.sync = 0;
1388 		lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1389 		bp = log->bp;
1390 		bp->l_ceor = bp->l_eor;
1391 		lp = (struct logpage *) bp->l_ldata;
1392 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1393 		lbmWrite(log, bp, lbmWRITE | lbmSYNC, 0);
1394 		if ((rc = lbmIOWait(bp, 0)))
1395 			goto errout30;
1396 
1397 		/*
1398 		 * update/write superblock
1399 		 */
1400 		logsuper->state = cpu_to_le32(LOGMOUNT);
1401 		log->serial = le32_to_cpu(logsuper->serial) + 1;
1402 		logsuper->serial = cpu_to_le32(log->serial);
1403 		lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1404 		if ((rc = lbmIOWait(bpsuper, lbmFREE)))
1405 			goto errout30;
1406 	}
1407 
1408 	/* initialize logsync parameters */
1409 	log->logsize = (log->size - 2) << L2LOGPSIZE;
1410 	log->lsn = lsn;
1411 	log->syncpt = lsn;
1412 	log->sync = log->syncpt;
1413 	log->nextsync = LOGSYNC_DELTA(log->logsize);
1414 
1415 	jfs_info("lmLogInit: lsn:0x%x syncpt:0x%x sync:0x%x",
1416 		 log->lsn, log->syncpt, log->sync);
1417 
1418 	/*
1419 	 * initialize for lazy/group commit
1420 	 */
1421 	log->clsn = lsn;
1422 
1423 	return 0;
1424 
1425 	/*
1426 	 *	unwind on error
1427 	 */
1428       errout30:		/* release log page */
1429 	log->wqueue = NULL;
1430 	bp->l_wqnext = NULL;
1431 	lbmFree(bp);
1432 
1433       errout20:		/* release log superblock */
1434 	lbmFree(bpsuper);
1435 
1436       errout10:		/* unwind lbmLogInit() */
1437 	lbmLogShutdown(log);
1438 
1439 	jfs_warn("lmLogInit: exit(%d)", rc);
1440 	return rc;
1441 }
1442 
1443 
1444 /*
1445  * NAME:	lmLogClose()
1446  *
1447  * FUNCTION:	remove file system <ipmnt> from active list of log <iplog>
1448  *		and close it on last close.
1449  *
1450  * PARAMETER:	sb	- superblock
1451  *
1452  * RETURN:	errors from subroutines
1453  *
1454  * serialization:
1455  */
lmLogClose(struct super_block * sb)1456 int lmLogClose(struct super_block *sb)
1457 {
1458 	struct jfs_sb_info *sbi = JFS_SBI(sb);
1459 	struct jfs_log *log = sbi->log;
1460 	struct block_device *bdev;
1461 	int rc = 0;
1462 
1463 	jfs_info("lmLogClose: log:0x%p", log);
1464 
1465 	mutex_lock(&jfs_log_mutex);
1466 	LOG_LOCK(log);
1467 	list_del(&sbi->log_list);
1468 	LOG_UNLOCK(log);
1469 	sbi->log = NULL;
1470 
1471 	/*
1472 	 * We need to make sure all of the "written" metapages
1473 	 * actually make it to disk
1474 	 */
1475 	sync_blockdev(sb->s_bdev);
1476 
1477 	if (test_bit(log_INLINELOG, &log->flag)) {
1478 		/*
1479 		 *	in-line log in host file system
1480 		 */
1481 		rc = lmLogShutdown(log);
1482 		kfree(log);
1483 		goto out;
1484 	}
1485 
1486 	if (!log->no_integrity)
1487 		lmLogFileSystem(log, sbi, 0);
1488 
1489 	if (!list_empty(&log->sb_list))
1490 		goto out;
1491 
1492 	/*
1493 	 * TODO: ensure that the dummy_log is in a state to allow
1494 	 * lbmLogShutdown to deallocate all the buffers and call
1495 	 * kfree against dummy_log.  For now, leave dummy_log & its
1496 	 * buffers in memory, and resuse if another no-integrity mount
1497 	 * is requested.
1498 	 */
1499 	if (log->no_integrity)
1500 		goto out;
1501 
1502 	/*
1503 	 *	external log as separate logical volume
1504 	 */
1505 	list_del(&log->journal_list);
1506 	bdev = log->bdev;
1507 	rc = lmLogShutdown(log);
1508 
1509 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1510 
1511 	kfree(log);
1512 
1513       out:
1514 	mutex_unlock(&jfs_log_mutex);
1515 	jfs_info("lmLogClose: exit(%d)", rc);
1516 	return rc;
1517 }
1518 
1519 
1520 /*
1521  * NAME:	jfs_flush_journal()
1522  *
1523  * FUNCTION:	initiate write of any outstanding transactions to the journal
1524  *		and optionally wait until they are all written to disk
1525  *
1526  *		wait == 0  flush until latest txn is committed, don't wait
1527  *		wait == 1  flush until latest txn is committed, wait
1528  *		wait > 1   flush until all txn's are complete, wait
1529  */
jfs_flush_journal(struct jfs_log * log,int wait)1530 void jfs_flush_journal(struct jfs_log *log, int wait)
1531 {
1532 	int i;
1533 	struct tblock *target = NULL;
1534 
1535 	/* jfs_write_inode may call us during read-only mount */
1536 	if (!log)
1537 		return;
1538 
1539 	jfs_info("jfs_flush_journal: log:0x%p wait=%d", log, wait);
1540 
1541 	LOGGC_LOCK(log);
1542 
1543 	if (!list_empty(&log->cqueue)) {
1544 		/*
1545 		 * This ensures that we will keep writing to the journal as long
1546 		 * as there are unwritten commit records
1547 		 */
1548 		target = list_entry(log->cqueue.prev, struct tblock, cqueue);
1549 
1550 		if (test_bit(log_FLUSH, &log->flag)) {
1551 			/*
1552 			 * We're already flushing.
1553 			 * if flush_tblk is NULL, we are flushing everything,
1554 			 * so leave it that way.  Otherwise, update it to the
1555 			 * latest transaction
1556 			 */
1557 			if (log->flush_tblk)
1558 				log->flush_tblk = target;
1559 		} else {
1560 			/* Only flush until latest transaction is committed */
1561 			log->flush_tblk = target;
1562 			set_bit(log_FLUSH, &log->flag);
1563 
1564 			/*
1565 			 * Initiate I/O on outstanding transactions
1566 			 */
1567 			if (!(log->cflag & logGC_PAGEOUT)) {
1568 				log->cflag |= logGC_PAGEOUT;
1569 				lmGCwrite(log, 0);
1570 			}
1571 		}
1572 	}
1573 	if ((wait > 1) || test_bit(log_SYNCBARRIER, &log->flag)) {
1574 		/* Flush until all activity complete */
1575 		set_bit(log_FLUSH, &log->flag);
1576 		log->flush_tblk = NULL;
1577 	}
1578 
1579 	if (wait && target && !(target->flag & tblkGC_COMMITTED)) {
1580 		DECLARE_WAITQUEUE(__wait, current);
1581 
1582 		add_wait_queue(&target->gcwait, &__wait);
1583 		set_current_state(TASK_UNINTERRUPTIBLE);
1584 		LOGGC_UNLOCK(log);
1585 		schedule();
1586 		__set_current_state(TASK_RUNNING);
1587 		LOGGC_LOCK(log);
1588 		remove_wait_queue(&target->gcwait, &__wait);
1589 	}
1590 	LOGGC_UNLOCK(log);
1591 
1592 	if (wait < 2)
1593 		return;
1594 
1595 	write_special_inodes(log, filemap_fdatawrite);
1596 
1597 	/*
1598 	 * If there was recent activity, we may need to wait
1599 	 * for the lazycommit thread to catch up
1600 	 */
1601 	if ((!list_empty(&log->cqueue)) || !list_empty(&log->synclist)) {
1602 		for (i = 0; i < 200; i++) {	/* Too much? */
1603 			msleep(250);
1604 			write_special_inodes(log, filemap_fdatawrite);
1605 			if (list_empty(&log->cqueue) &&
1606 			    list_empty(&log->synclist))
1607 				break;
1608 		}
1609 	}
1610 	assert(list_empty(&log->cqueue));
1611 
1612 #ifdef CONFIG_JFS_DEBUG
1613 	if (!list_empty(&log->synclist)) {
1614 		struct logsyncblk *lp;
1615 
1616 		printk(KERN_ERR "jfs_flush_journal: synclist not empty\n");
1617 		list_for_each_entry(lp, &log->synclist, synclist) {
1618 			if (lp->xflag & COMMIT_PAGE) {
1619 				struct metapage *mp = (struct metapage *)lp;
1620 				print_hex_dump(KERN_ERR, "metapage: ",
1621 					       DUMP_PREFIX_ADDRESS, 16, 4,
1622 					       mp, sizeof(struct metapage), 0);
1623 				print_hex_dump(KERN_ERR, "page: ",
1624 					       DUMP_PREFIX_ADDRESS, 16,
1625 					       sizeof(long), mp->page,
1626 					       sizeof(struct page), 0);
1627 			} else
1628 				print_hex_dump(KERN_ERR, "tblock:",
1629 					       DUMP_PREFIX_ADDRESS, 16, 4,
1630 					       lp, sizeof(struct tblock), 0);
1631 		}
1632 	}
1633 #else
1634 	WARN_ON(!list_empty(&log->synclist));
1635 #endif
1636 	clear_bit(log_FLUSH, &log->flag);
1637 }
1638 
1639 /*
1640  * NAME:	lmLogShutdown()
1641  *
1642  * FUNCTION:	log shutdown at last LogClose().
1643  *
1644  *		write log syncpt record.
1645  *		update super block to set redone flag to 0.
1646  *
1647  * PARAMETER:	log	- log inode
1648  *
1649  * RETURN:	0	- success
1650  *
1651  * serialization: single last close thread
1652  */
lmLogShutdown(struct jfs_log * log)1653 int lmLogShutdown(struct jfs_log * log)
1654 {
1655 	int rc;
1656 	struct lrd lrd;
1657 	int lsn;
1658 	struct logsuper *logsuper;
1659 	struct lbuf *bpsuper;
1660 	struct lbuf *bp;
1661 	struct logpage *lp;
1662 
1663 	jfs_info("lmLogShutdown: log:0x%p", log);
1664 
1665 	jfs_flush_journal(log, 2);
1666 
1667 	/*
1668 	 * write the last SYNCPT record with syncpoint = 0
1669 	 * (i.e., log redo up to HERE !)
1670 	 */
1671 	lrd.logtid = 0;
1672 	lrd.backchain = 0;
1673 	lrd.type = cpu_to_le16(LOG_SYNCPT);
1674 	lrd.length = 0;
1675 	lrd.log.syncpt.sync = 0;
1676 
1677 	lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1678 	bp = log->bp;
1679 	lp = (struct logpage *) bp->l_ldata;
1680 	lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1681 	lbmWrite(log, log->bp, lbmWRITE | lbmRELEASE | lbmSYNC, 0);
1682 	lbmIOWait(log->bp, lbmFREE);
1683 	log->bp = NULL;
1684 
1685 	/*
1686 	 * synchronous update log superblock
1687 	 * mark log state as shutdown cleanly
1688 	 * (i.e., Log does not need to be replayed).
1689 	 */
1690 	if ((rc = lbmRead(log, 1, &bpsuper)))
1691 		goto out;
1692 
1693 	logsuper = (struct logsuper *) bpsuper->l_ldata;
1694 	logsuper->state = cpu_to_le32(LOGREDONE);
1695 	logsuper->end = cpu_to_le32(lsn);
1696 	lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1697 	rc = lbmIOWait(bpsuper, lbmFREE);
1698 
1699 	jfs_info("lmLogShutdown: lsn:0x%x page:%d eor:%d",
1700 		 lsn, log->page, log->eor);
1701 
1702       out:
1703 	/*
1704 	 * shutdown per log i/o
1705 	 */
1706 	lbmLogShutdown(log);
1707 
1708 	if (rc) {
1709 		jfs_warn("lmLogShutdown: exit(%d)", rc);
1710 	}
1711 	return rc;
1712 }
1713 
1714 
1715 /*
1716  * NAME:	lmLogFileSystem()
1717  *
1718  * FUNCTION:	insert (<activate> = true)/remove (<activate> = false)
1719  *	file system into/from log active file system list.
1720  *
1721  * PARAMETE:	log	- pointer to logs inode.
1722  *		fsdev	- kdev_t of filesystem.
1723  *		serial	- pointer to returned log serial number
1724  *		activate - insert/remove device from active list.
1725  *
1726  * RETURN:	0	- success
1727  *		errors returned by vms_iowait().
1728  */
lmLogFileSystem(struct jfs_log * log,struct jfs_sb_info * sbi,int activate)1729 static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
1730 			   int activate)
1731 {
1732 	int rc = 0;
1733 	int i;
1734 	struct logsuper *logsuper;
1735 	struct lbuf *bpsuper;
1736 	char *uuid = sbi->uuid;
1737 
1738 	/*
1739 	 * insert/remove file system device to log active file system list.
1740 	 */
1741 	if ((rc = lbmRead(log, 1, &bpsuper)))
1742 		return rc;
1743 
1744 	logsuper = (struct logsuper *) bpsuper->l_ldata;
1745 	if (activate) {
1746 		for (i = 0; i < MAX_ACTIVE; i++)
1747 			if (!memcmp(logsuper->active[i].uuid, NULL_UUID, 16)) {
1748 				memcpy(logsuper->active[i].uuid, uuid, 16);
1749 				sbi->aggregate = i;
1750 				break;
1751 			}
1752 		if (i == MAX_ACTIVE) {
1753 			jfs_warn("Too many file systems sharing journal!");
1754 			lbmFree(bpsuper);
1755 			return -EMFILE;	/* Is there a better rc? */
1756 		}
1757 	} else {
1758 		for (i = 0; i < MAX_ACTIVE; i++)
1759 			if (!memcmp(logsuper->active[i].uuid, uuid, 16)) {
1760 				memcpy(logsuper->active[i].uuid, NULL_UUID, 16);
1761 				break;
1762 			}
1763 		if (i == MAX_ACTIVE) {
1764 			jfs_warn("Somebody stomped on the journal!");
1765 			lbmFree(bpsuper);
1766 			return -EIO;
1767 		}
1768 
1769 	}
1770 
1771 	/*
1772 	 * synchronous write log superblock:
1773 	 *
1774 	 * write sidestream bypassing write queue:
1775 	 * at file system mount, log super block is updated for
1776 	 * activation of the file system before any log record
1777 	 * (MOUNT record) of the file system, and at file system
1778 	 * unmount, all meta data for the file system has been
1779 	 * flushed before log super block is updated for deactivation
1780 	 * of the file system.
1781 	 */
1782 	lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1783 	rc = lbmIOWait(bpsuper, lbmFREE);
1784 
1785 	return rc;
1786 }
1787 
1788 /*
1789  *		log buffer manager (lbm)
1790  *		------------------------
1791  *
1792  * special purpose buffer manager supporting log i/o requirements.
1793  *
1794  * per log write queue:
1795  * log pageout occurs in serial order by fifo write queue and
1796  * restricting to a single i/o in pregress at any one time.
1797  * a circular singly-linked list
1798  * (log->wrqueue points to the tail, and buffers are linked via
1799  * bp->wrqueue field), and
1800  * maintains log page in pageout ot waiting for pageout in serial pageout.
1801  */
1802 
1803 /*
1804  *	lbmLogInit()
1805  *
1806  * initialize per log I/O setup at lmLogInit()
1807  */
lbmLogInit(struct jfs_log * log)1808 static int lbmLogInit(struct jfs_log * log)
1809 {				/* log inode */
1810 	int i;
1811 	struct lbuf *lbuf;
1812 
1813 	jfs_info("lbmLogInit: log:0x%p", log);
1814 
1815 	/* initialize current buffer cursor */
1816 	log->bp = NULL;
1817 
1818 	/* initialize log device write queue */
1819 	log->wqueue = NULL;
1820 
1821 	/*
1822 	 * Each log has its own buffer pages allocated to it.  These are
1823 	 * not managed by the page cache.  This ensures that a transaction
1824 	 * writing to the log does not block trying to allocate a page from
1825 	 * the page cache (for the log).  This would be bad, since page
1826 	 * allocation waits on the kswapd thread that may be committing inodes
1827 	 * which would cause log activity.  Was that clear?  I'm trying to
1828 	 * avoid deadlock here.
1829 	 */
1830 	init_waitqueue_head(&log->free_wait);
1831 
1832 	log->lbuf_free = NULL;
1833 
1834 	for (i = 0; i < LOGPAGES;) {
1835 		char *buffer;
1836 		uint offset;
1837 		struct page *page;
1838 
1839 		buffer = (char *) get_zeroed_page(GFP_KERNEL);
1840 		if (buffer == NULL)
1841 			goto error;
1842 		page = virt_to_page(buffer);
1843 		for (offset = 0; offset < PAGE_SIZE; offset += LOGPSIZE) {
1844 			lbuf = kmalloc(sizeof(struct lbuf), GFP_KERNEL);
1845 			if (lbuf == NULL) {
1846 				if (offset == 0)
1847 					free_page((unsigned long) buffer);
1848 				goto error;
1849 			}
1850 			if (offset) /* we already have one reference */
1851 				get_page(page);
1852 			lbuf->l_offset = offset;
1853 			lbuf->l_ldata = buffer + offset;
1854 			lbuf->l_page = page;
1855 			lbuf->l_log = log;
1856 			init_waitqueue_head(&lbuf->l_ioevent);
1857 
1858 			lbuf->l_freelist = log->lbuf_free;
1859 			log->lbuf_free = lbuf;
1860 			i++;
1861 		}
1862 	}
1863 
1864 	return (0);
1865 
1866       error:
1867 	lbmLogShutdown(log);
1868 	return -ENOMEM;
1869 }
1870 
1871 
1872 /*
1873  *	lbmLogShutdown()
1874  *
1875  * finalize per log I/O setup at lmLogShutdown()
1876  */
lbmLogShutdown(struct jfs_log * log)1877 static void lbmLogShutdown(struct jfs_log * log)
1878 {
1879 	struct lbuf *lbuf;
1880 
1881 	jfs_info("lbmLogShutdown: log:0x%p", log);
1882 
1883 	lbuf = log->lbuf_free;
1884 	while (lbuf) {
1885 		struct lbuf *next = lbuf->l_freelist;
1886 		__free_page(lbuf->l_page);
1887 		kfree(lbuf);
1888 		lbuf = next;
1889 	}
1890 }
1891 
1892 
1893 /*
1894  *	lbmAllocate()
1895  *
1896  * allocate an empty log buffer
1897  */
lbmAllocate(struct jfs_log * log,int pn)1898 static struct lbuf *lbmAllocate(struct jfs_log * log, int pn)
1899 {
1900 	struct lbuf *bp;
1901 	unsigned long flags;
1902 
1903 	/*
1904 	 * recycle from log buffer freelist if any
1905 	 */
1906 	LCACHE_LOCK(flags);
1907 	LCACHE_SLEEP_COND(log->free_wait, (bp = log->lbuf_free), flags);
1908 	log->lbuf_free = bp->l_freelist;
1909 	LCACHE_UNLOCK(flags);
1910 
1911 	bp->l_flag = 0;
1912 
1913 	bp->l_wqnext = NULL;
1914 	bp->l_freelist = NULL;
1915 
1916 	bp->l_pn = pn;
1917 	bp->l_blkno = log->base + (pn << (L2LOGPSIZE - log->l2bsize));
1918 	bp->l_ceor = 0;
1919 
1920 	return bp;
1921 }
1922 
1923 
1924 /*
1925  *	lbmFree()
1926  *
1927  * release a log buffer to freelist
1928  */
lbmFree(struct lbuf * bp)1929 static void lbmFree(struct lbuf * bp)
1930 {
1931 	unsigned long flags;
1932 
1933 	LCACHE_LOCK(flags);
1934 
1935 	lbmfree(bp);
1936 
1937 	LCACHE_UNLOCK(flags);
1938 }
1939 
lbmfree(struct lbuf * bp)1940 static void lbmfree(struct lbuf * bp)
1941 {
1942 	struct jfs_log *log = bp->l_log;
1943 
1944 	assert(bp->l_wqnext == NULL);
1945 
1946 	/*
1947 	 * return the buffer to head of freelist
1948 	 */
1949 	bp->l_freelist = log->lbuf_free;
1950 	log->lbuf_free = bp;
1951 
1952 	wake_up(&log->free_wait);
1953 	return;
1954 }
1955 
1956 
1957 /*
1958  * NAME:	lbmRedrive
1959  *
1960  * FUNCTION:	add a log buffer to the log redrive list
1961  *
1962  * PARAMETER:
1963  *	bp	- log buffer
1964  *
1965  * NOTES:
1966  *	Takes log_redrive_lock.
1967  */
lbmRedrive(struct lbuf * bp)1968 static inline void lbmRedrive(struct lbuf *bp)
1969 {
1970 	unsigned long flags;
1971 
1972 	spin_lock_irqsave(&log_redrive_lock, flags);
1973 	bp->l_redrive_next = log_redrive_list;
1974 	log_redrive_list = bp;
1975 	spin_unlock_irqrestore(&log_redrive_lock, flags);
1976 
1977 	wake_up_process(jfsIOthread);
1978 }
1979 
1980 
1981 /*
1982  *	lbmRead()
1983  */
lbmRead(struct jfs_log * log,int pn,struct lbuf ** bpp)1984 static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
1985 {
1986 	struct bio *bio;
1987 	struct lbuf *bp;
1988 
1989 	/*
1990 	 * allocate a log buffer
1991 	 */
1992 	*bpp = bp = lbmAllocate(log, pn);
1993 	jfs_info("lbmRead: bp:0x%p pn:0x%x", bp, pn);
1994 
1995 	bp->l_flag |= lbmREAD;
1996 
1997 	bio = bio_alloc(GFP_NOFS, 1);
1998 
1999 	bio->bi_sector = bp->l_blkno << (log->l2bsize - 9);
2000 	bio->bi_bdev = log->bdev;
2001 	bio->bi_io_vec[0].bv_page = bp->l_page;
2002 	bio->bi_io_vec[0].bv_len = LOGPSIZE;
2003 	bio->bi_io_vec[0].bv_offset = bp->l_offset;
2004 
2005 	bio->bi_vcnt = 1;
2006 	bio->bi_idx = 0;
2007 	bio->bi_size = LOGPSIZE;
2008 
2009 	bio->bi_end_io = lbmIODone;
2010 	bio->bi_private = bp;
2011 	submit_bio(READ_SYNC, bio);
2012 
2013 	wait_event(bp->l_ioevent, (bp->l_flag != lbmREAD));
2014 
2015 	return 0;
2016 }
2017 
2018 
2019 /*
2020  *	lbmWrite()
2021  *
2022  * buffer at head of pageout queue stays after completion of
2023  * partial-page pageout and redriven by explicit initiation of
2024  * pageout by caller until full-page pageout is completed and
2025  * released.
2026  *
2027  * device driver i/o done redrives pageout of new buffer at
2028  * head of pageout queue when current buffer at head of pageout
2029  * queue is released at the completion of its full-page pageout.
2030  *
2031  * LOGGC_LOCK() serializes lbmWrite() by lmNextPage() and lmGroupCommit().
2032  * LCACHE_LOCK() serializes xflag between lbmWrite() and lbmIODone()
2033  */
lbmWrite(struct jfs_log * log,struct lbuf * bp,int flag,int cant_block)2034 static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag,
2035 		     int cant_block)
2036 {
2037 	struct lbuf *tail;
2038 	unsigned long flags;
2039 
2040 	jfs_info("lbmWrite: bp:0x%p flag:0x%x pn:0x%x", bp, flag, bp->l_pn);
2041 
2042 	/* map the logical block address to physical block address */
2043 	bp->l_blkno =
2044 	    log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2045 
2046 	LCACHE_LOCK(flags);		/* disable+lock */
2047 
2048 	/*
2049 	 * initialize buffer for device driver
2050 	 */
2051 	bp->l_flag = flag;
2052 
2053 	/*
2054 	 *	insert bp at tail of write queue associated with log
2055 	 *
2056 	 * (request is either for bp already/currently at head of queue
2057 	 * or new bp to be inserted at tail)
2058 	 */
2059 	tail = log->wqueue;
2060 
2061 	/* is buffer not already on write queue ? */
2062 	if (bp->l_wqnext == NULL) {
2063 		/* insert at tail of wqueue */
2064 		if (tail == NULL) {
2065 			log->wqueue = bp;
2066 			bp->l_wqnext = bp;
2067 		} else {
2068 			log->wqueue = bp;
2069 			bp->l_wqnext = tail->l_wqnext;
2070 			tail->l_wqnext = bp;
2071 		}
2072 
2073 		tail = bp;
2074 	}
2075 
2076 	/* is buffer at head of wqueue and for write ? */
2077 	if ((bp != tail->l_wqnext) || !(flag & lbmWRITE)) {
2078 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2079 		return;
2080 	}
2081 
2082 	LCACHE_UNLOCK(flags);	/* unlock+enable */
2083 
2084 	if (cant_block)
2085 		lbmRedrive(bp);
2086 	else if (flag & lbmSYNC)
2087 		lbmStartIO(bp);
2088 	else {
2089 		LOGGC_UNLOCK(log);
2090 		lbmStartIO(bp);
2091 		LOGGC_LOCK(log);
2092 	}
2093 }
2094 
2095 
2096 /*
2097  *	lbmDirectWrite()
2098  *
2099  * initiate pageout bypassing write queue for sidestream
2100  * (e.g., log superblock) write;
2101  */
lbmDirectWrite(struct jfs_log * log,struct lbuf * bp,int flag)2102 static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag)
2103 {
2104 	jfs_info("lbmDirectWrite: bp:0x%p flag:0x%x pn:0x%x",
2105 		 bp, flag, bp->l_pn);
2106 
2107 	/*
2108 	 * initialize buffer for device driver
2109 	 */
2110 	bp->l_flag = flag | lbmDIRECT;
2111 
2112 	/* map the logical block address to physical block address */
2113 	bp->l_blkno =
2114 	    log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2115 
2116 	/*
2117 	 *	initiate pageout of the page
2118 	 */
2119 	lbmStartIO(bp);
2120 }
2121 
2122 
2123 /*
2124  * NAME:	lbmStartIO()
2125  *
2126  * FUNCTION:	Interface to DD strategy routine
2127  *
2128  * RETURN:	none
2129  *
2130  * serialization: LCACHE_LOCK() is NOT held during log i/o;
2131  */
lbmStartIO(struct lbuf * bp)2132 static void lbmStartIO(struct lbuf * bp)
2133 {
2134 	struct bio *bio;
2135 	struct jfs_log *log = bp->l_log;
2136 
2137 	jfs_info("lbmStartIO\n");
2138 
2139 	bio = bio_alloc(GFP_NOFS, 1);
2140 	bio->bi_sector = bp->l_blkno << (log->l2bsize - 9);
2141 	bio->bi_bdev = log->bdev;
2142 	bio->bi_io_vec[0].bv_page = bp->l_page;
2143 	bio->bi_io_vec[0].bv_len = LOGPSIZE;
2144 	bio->bi_io_vec[0].bv_offset = bp->l_offset;
2145 
2146 	bio->bi_vcnt = 1;
2147 	bio->bi_idx = 0;
2148 	bio->bi_size = LOGPSIZE;
2149 
2150 	bio->bi_end_io = lbmIODone;
2151 	bio->bi_private = bp;
2152 
2153 	/* check if journaling to disk has been disabled */
2154 	if (log->no_integrity) {
2155 		bio->bi_size = 0;
2156 		lbmIODone(bio, 0);
2157 	} else {
2158 		submit_bio(WRITE_SYNC, bio);
2159 		INCREMENT(lmStat.submitted);
2160 	}
2161 }
2162 
2163 
2164 /*
2165  *	lbmIOWait()
2166  */
lbmIOWait(struct lbuf * bp,int flag)2167 static int lbmIOWait(struct lbuf * bp, int flag)
2168 {
2169 	unsigned long flags;
2170 	int rc = 0;
2171 
2172 	jfs_info("lbmIOWait1: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2173 
2174 	LCACHE_LOCK(flags);		/* disable+lock */
2175 
2176 	LCACHE_SLEEP_COND(bp->l_ioevent, (bp->l_flag & lbmDONE), flags);
2177 
2178 	rc = (bp->l_flag & lbmERROR) ? -EIO : 0;
2179 
2180 	if (flag & lbmFREE)
2181 		lbmfree(bp);
2182 
2183 	LCACHE_UNLOCK(flags);	/* unlock+enable */
2184 
2185 	jfs_info("lbmIOWait2: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2186 	return rc;
2187 }
2188 
2189 /*
2190  *	lbmIODone()
2191  *
2192  * executed at INTIODONE level
2193  */
lbmIODone(struct bio * bio,int error)2194 static void lbmIODone(struct bio *bio, int error)
2195 {
2196 	struct lbuf *bp = bio->bi_private;
2197 	struct lbuf *nextbp, *tail;
2198 	struct jfs_log *log;
2199 	unsigned long flags;
2200 
2201 	/*
2202 	 * get back jfs buffer bound to the i/o buffer
2203 	 */
2204 	jfs_info("lbmIODone: bp:0x%p flag:0x%x", bp, bp->l_flag);
2205 
2206 	LCACHE_LOCK(flags);		/* disable+lock */
2207 
2208 	bp->l_flag |= lbmDONE;
2209 
2210 	if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) {
2211 		bp->l_flag |= lbmERROR;
2212 
2213 		jfs_err("lbmIODone: I/O error in JFS log");
2214 	}
2215 
2216 	bio_put(bio);
2217 
2218 	/*
2219 	 *	pagein completion
2220 	 */
2221 	if (bp->l_flag & lbmREAD) {
2222 		bp->l_flag &= ~lbmREAD;
2223 
2224 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2225 
2226 		/* wakeup I/O initiator */
2227 		LCACHE_WAKEUP(&bp->l_ioevent);
2228 
2229 		return;
2230 	}
2231 
2232 	/*
2233 	 *	pageout completion
2234 	 *
2235 	 * the bp at the head of write queue has completed pageout.
2236 	 *
2237 	 * if single-commit/full-page pageout, remove the current buffer
2238 	 * from head of pageout queue, and redrive pageout with
2239 	 * the new buffer at head of pageout queue;
2240 	 * otherwise, the partial-page pageout buffer stays at
2241 	 * the head of pageout queue to be redriven for pageout
2242 	 * by lmGroupCommit() until full-page pageout is completed.
2243 	 */
2244 	bp->l_flag &= ~lbmWRITE;
2245 	INCREMENT(lmStat.pagedone);
2246 
2247 	/* update committed lsn */
2248 	log = bp->l_log;
2249 	log->clsn = (bp->l_pn << L2LOGPSIZE) + bp->l_ceor;
2250 
2251 	if (bp->l_flag & lbmDIRECT) {
2252 		LCACHE_WAKEUP(&bp->l_ioevent);
2253 		LCACHE_UNLOCK(flags);
2254 		return;
2255 	}
2256 
2257 	tail = log->wqueue;
2258 
2259 	/* single element queue */
2260 	if (bp == tail) {
2261 		/* remove head buffer of full-page pageout
2262 		 * from log device write queue
2263 		 */
2264 		if (bp->l_flag & lbmRELEASE) {
2265 			log->wqueue = NULL;
2266 			bp->l_wqnext = NULL;
2267 		}
2268 	}
2269 	/* multi element queue */
2270 	else {
2271 		/* remove head buffer of full-page pageout
2272 		 * from log device write queue
2273 		 */
2274 		if (bp->l_flag & lbmRELEASE) {
2275 			nextbp = tail->l_wqnext = bp->l_wqnext;
2276 			bp->l_wqnext = NULL;
2277 
2278 			/*
2279 			 * redrive pageout of next page at head of write queue:
2280 			 * redrive next page without any bound tblk
2281 			 * (i.e., page w/o any COMMIT records), or
2282 			 * first page of new group commit which has been
2283 			 * queued after current page (subsequent pageout
2284 			 * is performed synchronously, except page without
2285 			 * any COMMITs) by lmGroupCommit() as indicated
2286 			 * by lbmWRITE flag;
2287 			 */
2288 			if (nextbp->l_flag & lbmWRITE) {
2289 				/*
2290 				 * We can't do the I/O at interrupt time.
2291 				 * The jfsIO thread can do it
2292 				 */
2293 				lbmRedrive(nextbp);
2294 			}
2295 		}
2296 	}
2297 
2298 	/*
2299 	 *	synchronous pageout:
2300 	 *
2301 	 * buffer has not necessarily been removed from write queue
2302 	 * (e.g., synchronous write of partial-page with COMMIT):
2303 	 * leave buffer for i/o initiator to dispose
2304 	 */
2305 	if (bp->l_flag & lbmSYNC) {
2306 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2307 
2308 		/* wakeup I/O initiator */
2309 		LCACHE_WAKEUP(&bp->l_ioevent);
2310 	}
2311 
2312 	/*
2313 	 *	Group Commit pageout:
2314 	 */
2315 	else if (bp->l_flag & lbmGC) {
2316 		LCACHE_UNLOCK(flags);
2317 		lmPostGC(bp);
2318 	}
2319 
2320 	/*
2321 	 *	asynchronous pageout:
2322 	 *
2323 	 * buffer must have been removed from write queue:
2324 	 * insert buffer at head of freelist where it can be recycled
2325 	 */
2326 	else {
2327 		assert(bp->l_flag & lbmRELEASE);
2328 		assert(bp->l_flag & lbmFREE);
2329 		lbmfree(bp);
2330 
2331 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2332 	}
2333 }
2334 
jfsIOWait(void * arg)2335 int jfsIOWait(void *arg)
2336 {
2337 	struct lbuf *bp;
2338 
2339 	do {
2340 		spin_lock_irq(&log_redrive_lock);
2341 		while ((bp = log_redrive_list)) {
2342 			log_redrive_list = bp->l_redrive_next;
2343 			bp->l_redrive_next = NULL;
2344 			spin_unlock_irq(&log_redrive_lock);
2345 			lbmStartIO(bp);
2346 			spin_lock_irq(&log_redrive_lock);
2347 		}
2348 
2349 		if (freezing(current)) {
2350 			spin_unlock_irq(&log_redrive_lock);
2351 			refrigerator();
2352 		} else {
2353 			set_current_state(TASK_INTERRUPTIBLE);
2354 			spin_unlock_irq(&log_redrive_lock);
2355 			schedule();
2356 			__set_current_state(TASK_RUNNING);
2357 		}
2358 	} while (!kthread_should_stop());
2359 
2360 	jfs_info("jfsIOWait being killed!");
2361 	return 0;
2362 }
2363 
2364 /*
2365  * NAME:	lmLogFormat()/jfs_logform()
2366  *
2367  * FUNCTION:	format file system log
2368  *
2369  * PARAMETERS:
2370  *	log	- volume log
2371  *	logAddress - start address of log space in FS block
2372  *	logSize	- length of log space in FS block;
2373  *
2374  * RETURN:	0	- success
2375  *		-EIO	- i/o error
2376  *
2377  * XXX: We're synchronously writing one page at a time.  This needs to
2378  *	be improved by writing multiple pages at once.
2379  */
lmLogFormat(struct jfs_log * log,s64 logAddress,int logSize)2380 int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize)
2381 {
2382 	int rc = -EIO;
2383 	struct jfs_sb_info *sbi;
2384 	struct logsuper *logsuper;
2385 	struct logpage *lp;
2386 	int lspn;		/* log sequence page number */
2387 	struct lrd *lrd_ptr;
2388 	int npages = 0;
2389 	struct lbuf *bp;
2390 
2391 	jfs_info("lmLogFormat: logAddress:%Ld logSize:%d",
2392 		 (long long)logAddress, logSize);
2393 
2394 	sbi = list_entry(log->sb_list.next, struct jfs_sb_info, log_list);
2395 
2396 	/* allocate a log buffer */
2397 	bp = lbmAllocate(log, 1);
2398 
2399 	npages = logSize >> sbi->l2nbperpage;
2400 
2401 	/*
2402 	 *	log space:
2403 	 *
2404 	 * page 0 - reserved;
2405 	 * page 1 - log superblock;
2406 	 * page 2 - log data page: A SYNC log record is written
2407 	 *	    into this page at logform time;
2408 	 * pages 3-N - log data page: set to empty log data pages;
2409 	 */
2410 	/*
2411 	 *	init log superblock: log page 1
2412 	 */
2413 	logsuper = (struct logsuper *) bp->l_ldata;
2414 
2415 	logsuper->magic = cpu_to_le32(LOGMAGIC);
2416 	logsuper->version = cpu_to_le32(LOGVERSION);
2417 	logsuper->state = cpu_to_le32(LOGREDONE);
2418 	logsuper->flag = cpu_to_le32(sbi->mntflag);	/* ? */
2419 	logsuper->size = cpu_to_le32(npages);
2420 	logsuper->bsize = cpu_to_le32(sbi->bsize);
2421 	logsuper->l2bsize = cpu_to_le32(sbi->l2bsize);
2422 	logsuper->end = cpu_to_le32(2 * LOGPSIZE + LOGPHDRSIZE + LOGRDSIZE);
2423 
2424 	bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2425 	bp->l_blkno = logAddress + sbi->nbperpage;
2426 	lbmStartIO(bp);
2427 	if ((rc = lbmIOWait(bp, 0)))
2428 		goto exit;
2429 
2430 	/*
2431 	 *	init pages 2 to npages-1 as log data pages:
2432 	 *
2433 	 * log page sequence number (lpsn) initialization:
2434 	 *
2435 	 * pn:   0     1     2     3                 n-1
2436 	 *       +-----+-----+=====+=====+===.....===+=====+
2437 	 * lspn:             N-1   0     1           N-2
2438 	 *                   <--- N page circular file ---->
2439 	 *
2440 	 * the N (= npages-2) data pages of the log is maintained as
2441 	 * a circular file for the log records;
2442 	 * lpsn grows by 1 monotonically as each log page is written
2443 	 * to the circular file of the log;
2444 	 * and setLogpage() will not reset the page number even if
2445 	 * the eor is equal to LOGPHDRSIZE. In order for binary search
2446 	 * still work in find log end process, we have to simulate the
2447 	 * log wrap situation at the log format time.
2448 	 * The 1st log page written will have the highest lpsn. Then
2449 	 * the succeeding log pages will have ascending order of
2450 	 * the lspn starting from 0, ... (N-2)
2451 	 */
2452 	lp = (struct logpage *) bp->l_ldata;
2453 	/*
2454 	 * initialize 1st log page to be written: lpsn = N - 1,
2455 	 * write a SYNCPT log record is written to this page
2456 	 */
2457 	lp->h.page = lp->t.page = cpu_to_le32(npages - 3);
2458 	lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE + LOGRDSIZE);
2459 
2460 	lrd_ptr = (struct lrd *) &lp->data;
2461 	lrd_ptr->logtid = 0;
2462 	lrd_ptr->backchain = 0;
2463 	lrd_ptr->type = cpu_to_le16(LOG_SYNCPT);
2464 	lrd_ptr->length = 0;
2465 	lrd_ptr->log.syncpt.sync = 0;
2466 
2467 	bp->l_blkno += sbi->nbperpage;
2468 	bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2469 	lbmStartIO(bp);
2470 	if ((rc = lbmIOWait(bp, 0)))
2471 		goto exit;
2472 
2473 	/*
2474 	 *	initialize succeeding log pages: lpsn = 0, 1, ..., (N-2)
2475 	 */
2476 	for (lspn = 0; lspn < npages - 3; lspn++) {
2477 		lp->h.page = lp->t.page = cpu_to_le32(lspn);
2478 		lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
2479 
2480 		bp->l_blkno += sbi->nbperpage;
2481 		bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2482 		lbmStartIO(bp);
2483 		if ((rc = lbmIOWait(bp, 0)))
2484 			goto exit;
2485 	}
2486 
2487 	rc = 0;
2488 exit:
2489 	/*
2490 	 *	finalize log
2491 	 */
2492 	/* release the buffer */
2493 	lbmFree(bp);
2494 
2495 	return rc;
2496 }
2497 
2498 #ifdef CONFIG_JFS_STATISTICS
jfs_lmstats_proc_show(struct seq_file * m,void * v)2499 static int jfs_lmstats_proc_show(struct seq_file *m, void *v)
2500 {
2501 	seq_printf(m,
2502 		       "JFS Logmgr stats\n"
2503 		       "================\n"
2504 		       "commits = %d\n"
2505 		       "writes submitted = %d\n"
2506 		       "writes completed = %d\n"
2507 		       "full pages submitted = %d\n"
2508 		       "partial pages submitted = %d\n",
2509 		       lmStat.commit,
2510 		       lmStat.submitted,
2511 		       lmStat.pagedone,
2512 		       lmStat.full_page,
2513 		       lmStat.partial_page);
2514 	return 0;
2515 }
2516 
jfs_lmstats_proc_open(struct inode * inode,struct file * file)2517 static int jfs_lmstats_proc_open(struct inode *inode, struct file *file)
2518 {
2519 	return single_open(file, jfs_lmstats_proc_show, NULL);
2520 }
2521 
2522 const struct file_operations jfs_lmstats_proc_fops = {
2523 	.owner		= THIS_MODULE,
2524 	.open		= jfs_lmstats_proc_open,
2525 	.read		= seq_read,
2526 	.llseek		= seq_lseek,
2527 	.release	= single_release,
2528 };
2529 #endif /* CONFIG_JFS_STATISTICS */
2530