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