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1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Copyright (C) International Business Machines Corp., 2000-2004
4  *   Portions Copyright (C) Christoph Hellwig, 2001-2002
5  */
6 
7 /*
8  *	jfs_logmgr.c: log manager
9  *
10  * for related information, see transaction manager (jfs_txnmgr.c), and
11  * recovery manager (jfs_logredo.c).
12  *
13  * note: for detail, RTFS.
14  *
15  *	log buffer manager:
16  * special purpose buffer manager supporting log i/o requirements.
17  * per log serial pageout of logpage
18  * queuing i/o requests and redrive i/o at iodone
19  * maintain current logpage buffer
20  * no caching since append only
21  * appropriate jfs buffer cache buffers as needed
22  *
23  *	group commit:
24  * transactions which wrote COMMIT records in the same in-memory
25  * log page during the pageout of previous/current log page(s) are
26  * committed together by the pageout of the page.
27  *
28  *	TBD lazy commit:
29  * transactions are committed asynchronously when the log page
30  * containing it COMMIT is paged out when it becomes full;
31  *
32  *	serialization:
33  * . a per log lock serialize log write.
34  * . a per log lock serialize group commit.
35  * . a per log lock serialize log open/close;
36  *
37  *	TBD log integrity:
38  * careful-write (ping-pong) of last logpage to recover from crash
39  * in overwrite.
40  * detection of split (out-of-order) write of physical sectors
41  * of last logpage via timestamp at end of each sector
42  * with its mirror data array at trailer).
43  *
44  *	alternatives:
45  * lsn - 64-bit monotonically increasing integer vs
46  * 32-bit lspn and page eor.
47  */
48 
49 #include <linux/fs.h>
50 #include <linux/blkdev.h>
51 #include <linux/interrupt.h>
52 #include <linux/completion.h>
53 #include <linux/kthread.h>
54 #include <linux/buffer_head.h>		/* for sync_blockdev() */
55 #include <linux/bio.h>
56 #include <linux/freezer.h>
57 #include <linux/export.h>
58 #include <linux/delay.h>
59 #include <linux/mutex.h>
60 #include <linux/seq_file.h>
61 #include <linux/slab.h>
62 #include "jfs_incore.h"
63 #include "jfs_filsys.h"
64 #include "jfs_metapage.h"
65 #include "jfs_superblock.h"
66 #include "jfs_txnmgr.h"
67 #include "jfs_debug.h"
68 
69 
70 /*
71  * lbuf's ready to be redriven.  Protected by log_redrive_lock (jfsIO thread)
72  */
73 static struct lbuf *log_redrive_list;
74 static DEFINE_SPINLOCK(log_redrive_lock);
75 
76 
77 /*
78  *	log read/write serialization (per log)
79  */
80 #define LOG_LOCK_INIT(log)	mutex_init(&(log)->loglock)
81 #define LOG_LOCK(log)		mutex_lock(&((log)->loglock))
82 #define LOG_UNLOCK(log)		mutex_unlock(&((log)->loglock))
83 
84 
85 /*
86  *	log group commit serialization (per log)
87  */
88 
89 #define LOGGC_LOCK_INIT(log)	spin_lock_init(&(log)->gclock)
90 #define LOGGC_LOCK(log)		spin_lock_irq(&(log)->gclock)
91 #define LOGGC_UNLOCK(log)	spin_unlock_irq(&(log)->gclock)
92 #define LOGGC_WAKEUP(tblk)	wake_up_all(&(tblk)->gcwait)
93 
94 /*
95  *	log sync serialization (per log)
96  */
97 #define	LOGSYNC_DELTA(logsize)		min((logsize)/8, 128*LOGPSIZE)
98 #define	LOGSYNC_BARRIER(logsize)	((logsize)/4)
99 /*
100 #define	LOGSYNC_DELTA(logsize)		min((logsize)/4, 256*LOGPSIZE)
101 #define	LOGSYNC_BARRIER(logsize)	((logsize)/2)
102 */
103 
104 
105 /*
106  *	log buffer cache synchronization
107  */
108 static DEFINE_SPINLOCK(jfsLCacheLock);
109 
110 #define	LCACHE_LOCK(flags)	spin_lock_irqsave(&jfsLCacheLock, flags)
111 #define	LCACHE_UNLOCK(flags)	spin_unlock_irqrestore(&jfsLCacheLock, flags)
112 
113 /*
114  * See __SLEEP_COND in jfs_locks.h
115  */
116 #define LCACHE_SLEEP_COND(wq, cond, flags)	\
117 do {						\
118 	if (cond)				\
119 		break;				\
120 	__SLEEP_COND(wq, cond, LCACHE_LOCK(flags), LCACHE_UNLOCK(flags)); \
121 } while (0)
122 
123 #define	LCACHE_WAKEUP(event)	wake_up(event)
124 
125 
126 /*
127  *	lbuf buffer cache (lCache) control
128  */
129 /* log buffer manager pageout control (cumulative, inclusive) */
130 #define	lbmREAD		0x0001
131 #define	lbmWRITE	0x0002	/* enqueue at tail of write queue;
132 				 * init pageout if at head of queue;
133 				 */
134 #define	lbmRELEASE	0x0004	/* remove from write queue
135 				 * at completion of pageout;
136 				 * do not free/recycle it yet:
137 				 * caller will free it;
138 				 */
139 #define	lbmSYNC		0x0008	/* do not return to freelist
140 				 * when removed from write queue;
141 				 */
142 #define lbmFREE		0x0010	/* return to freelist
143 				 * at completion of pageout;
144 				 * the buffer may be recycled;
145 				 */
146 #define	lbmDONE		0x0020
147 #define	lbmERROR	0x0040
148 #define lbmGC		0x0080	/* lbmIODone to perform post-GC processing
149 				 * of log page
150 				 */
151 #define lbmDIRECT	0x0100
152 
153 /*
154  * Global list of active external journals
155  */
156 static LIST_HEAD(jfs_external_logs);
157 static struct jfs_log *dummy_log;
158 static DEFINE_MUTEX(jfs_log_mutex);
159 
160 /*
161  * forward references
162  */
163 static int lmWriteRecord(struct jfs_log * log, struct tblock * tblk,
164 			 struct lrd * lrd, struct tlock * tlck);
165 
166 static int lmNextPage(struct jfs_log * log);
167 static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
168 			   int activate);
169 
170 static int open_inline_log(struct super_block *sb);
171 static int open_dummy_log(struct super_block *sb);
172 static int lbmLogInit(struct jfs_log * log);
173 static void lbmLogShutdown(struct jfs_log * log);
174 static struct lbuf *lbmAllocate(struct jfs_log * log, int);
175 static void lbmFree(struct lbuf * bp);
176 static void lbmfree(struct lbuf * bp);
177 static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp);
178 static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag, int cant_block);
179 static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag);
180 static int lbmIOWait(struct lbuf * bp, int flag);
181 static bio_end_io_t lbmIODone;
182 static void lbmStartIO(struct lbuf * bp);
183 static void lmGCwrite(struct jfs_log * log, int cant_block);
184 static int lmLogSync(struct jfs_log * log, int hard_sync);
185 
186 
187 
188 /*
189  *	statistics
190  */
191 #ifdef CONFIG_JFS_STATISTICS
192 static struct lmStat {
193 	uint commit;		/* # of commit */
194 	uint pagedone;		/* # of page written */
195 	uint submitted;		/* # of pages submitted */
196 	uint full_page;		/* # of full pages submitted */
197 	uint partial_page;	/* # of partial pages submitted */
198 } lmStat;
199 #endif
200 
write_special_inodes(struct jfs_log * log,int (* writer)(struct address_space *))201 static void write_special_inodes(struct jfs_log *log,
202 				 int (*writer)(struct address_space *))
203 {
204 	struct jfs_sb_info *sbi;
205 
206 	list_for_each_entry(sbi, &log->sb_list, log_list) {
207 		writer(sbi->ipbmap->i_mapping);
208 		writer(sbi->ipimap->i_mapping);
209 		writer(sbi->direct_inode->i_mapping);
210 	}
211 }
212 
213 /*
214  * NAME:	lmLog()
215  *
216  * FUNCTION:	write a log record;
217  *
218  * PARAMETER:
219  *
220  * RETURN:	lsn - offset to the next log record to write (end-of-log);
221  *		-1  - error;
222  *
223  * note: todo: log error handler
224  */
lmLog(struct jfs_log * log,struct tblock * tblk,struct lrd * lrd,struct tlock * tlck)225 int lmLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
226 	  struct tlock * tlck)
227 {
228 	int lsn;
229 	int diffp, difft;
230 	struct metapage *mp = NULL;
231 	unsigned long flags;
232 
233 	jfs_info("lmLog: log:0x%p tblk:0x%p, lrd:0x%p tlck:0x%p",
234 		 log, tblk, lrd, tlck);
235 
236 	LOG_LOCK(log);
237 
238 	/* log by (out-of-transaction) JFS ? */
239 	if (tblk == NULL)
240 		goto writeRecord;
241 
242 	/* log from page ? */
243 	if (tlck == NULL ||
244 	    tlck->type & tlckBTROOT || (mp = tlck->mp) == NULL)
245 		goto writeRecord;
246 
247 	/*
248 	 *	initialize/update page/transaction recovery lsn
249 	 */
250 	lsn = log->lsn;
251 
252 	LOGSYNC_LOCK(log, flags);
253 
254 	/*
255 	 * initialize page lsn if first log write of the page
256 	 */
257 	if (mp->lsn == 0) {
258 		mp->log = log;
259 		mp->lsn = lsn;
260 		log->count++;
261 
262 		/* insert page at tail of logsynclist */
263 		list_add_tail(&mp->synclist, &log->synclist);
264 	}
265 
266 	/*
267 	 *	initialize/update lsn of tblock of the page
268 	 *
269 	 * transaction inherits oldest lsn of pages associated
270 	 * with allocation/deallocation of resources (their
271 	 * log records are used to reconstruct allocation map
272 	 * at recovery time: inode for inode allocation map,
273 	 * B+-tree index of extent descriptors for block
274 	 * allocation map);
275 	 * allocation map pages inherit transaction lsn at
276 	 * commit time to allow forwarding log syncpt past log
277 	 * records associated with allocation/deallocation of
278 	 * resources only after persistent map of these map pages
279 	 * have been updated and propagated to home.
280 	 */
281 	/*
282 	 * initialize transaction lsn:
283 	 */
284 	if (tblk->lsn == 0) {
285 		/* inherit lsn of its first page logged */
286 		tblk->lsn = mp->lsn;
287 		log->count++;
288 
289 		/* insert tblock after the page on logsynclist */
290 		list_add(&tblk->synclist, &mp->synclist);
291 	}
292 	/*
293 	 * update transaction lsn:
294 	 */
295 	else {
296 		/* inherit oldest/smallest lsn of page */
297 		logdiff(diffp, mp->lsn, log);
298 		logdiff(difft, tblk->lsn, log);
299 		if (diffp < difft) {
300 			/* update tblock lsn with page lsn */
301 			tblk->lsn = mp->lsn;
302 
303 			/* move tblock after page on logsynclist */
304 			list_move(&tblk->synclist, &mp->synclist);
305 		}
306 	}
307 
308 	LOGSYNC_UNLOCK(log, flags);
309 
310 	/*
311 	 *	write the log record
312 	 */
313       writeRecord:
314 	lsn = lmWriteRecord(log, tblk, lrd, tlck);
315 
316 	/*
317 	 * forward log syncpt if log reached next syncpt trigger
318 	 */
319 	logdiff(diffp, lsn, log);
320 	if (diffp >= log->nextsync)
321 		lsn = lmLogSync(log, 0);
322 
323 	/* update end-of-log lsn */
324 	log->lsn = lsn;
325 
326 	LOG_UNLOCK(log);
327 
328 	/* return end-of-log address */
329 	return lsn;
330 }
331 
332 /*
333  * NAME:	lmWriteRecord()
334  *
335  * FUNCTION:	move the log record to current log page
336  *
337  * PARAMETER:	cd	- commit descriptor
338  *
339  * RETURN:	end-of-log address
340  *
341  * serialization: LOG_LOCK() held on entry/exit
342  */
343 static int
lmWriteRecord(struct jfs_log * log,struct tblock * tblk,struct lrd * lrd,struct tlock * tlck)344 lmWriteRecord(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
345 	      struct tlock * tlck)
346 {
347 	int lsn = 0;		/* end-of-log address */
348 	struct lbuf *bp;	/* dst log page buffer */
349 	struct logpage *lp;	/* dst log page */
350 	caddr_t dst;		/* destination address in log page */
351 	int dstoffset;		/* end-of-log offset in log page */
352 	int freespace;		/* free space in log page */
353 	caddr_t p;		/* src meta-data page */
354 	caddr_t src;
355 	int srclen;
356 	int nbytes;		/* number of bytes to move */
357 	int i;
358 	int len;
359 	struct linelock *linelock;
360 	struct lv *lv;
361 	struct lvd *lvd;
362 	int l2linesize;
363 
364 	len = 0;
365 
366 	/* retrieve destination log page to write */
367 	bp = (struct lbuf *) log->bp;
368 	lp = (struct logpage *) bp->l_ldata;
369 	dstoffset = log->eor;
370 
371 	/* any log data to write ? */
372 	if (tlck == NULL)
373 		goto moveLrd;
374 
375 	/*
376 	 *	move log record data
377 	 */
378 	/* retrieve source meta-data page to log */
379 	if (tlck->flag & tlckPAGELOCK) {
380 		p = (caddr_t) (tlck->mp->data);
381 		linelock = (struct linelock *) & tlck->lock;
382 	}
383 	/* retrieve source in-memory inode to log */
384 	else if (tlck->flag & tlckINODELOCK) {
385 		if (tlck->type & tlckDTREE)
386 			p = (caddr_t) &JFS_IP(tlck->ip)->i_dtroot;
387 		else
388 			p = (caddr_t) &JFS_IP(tlck->ip)->i_xtroot;
389 		linelock = (struct linelock *) & tlck->lock;
390 	}
391 	else {
392 		jfs_err("lmWriteRecord: UFO tlck:0x%p", tlck);
393 		return 0;	/* Probably should trap */
394 	}
395 	l2linesize = linelock->l2linesize;
396 
397       moveData:
398 	ASSERT(linelock->index <= linelock->maxcnt);
399 
400 	lv = linelock->lv;
401 	for (i = 0; i < linelock->index; i++, lv++) {
402 		if (lv->length == 0)
403 			continue;
404 
405 		/* is page full ? */
406 		if (dstoffset >= LOGPSIZE - LOGPTLRSIZE) {
407 			/* page become full: move on to next page */
408 			lmNextPage(log);
409 
410 			bp = log->bp;
411 			lp = (struct logpage *) bp->l_ldata;
412 			dstoffset = LOGPHDRSIZE;
413 		}
414 
415 		/*
416 		 * move log vector data
417 		 */
418 		src = (u8 *) p + (lv->offset << l2linesize);
419 		srclen = lv->length << l2linesize;
420 		len += srclen;
421 		while (srclen > 0) {
422 			freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
423 			nbytes = min(freespace, srclen);
424 			dst = (caddr_t) lp + dstoffset;
425 			memcpy(dst, src, nbytes);
426 			dstoffset += nbytes;
427 
428 			/* is page not full ? */
429 			if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
430 				break;
431 
432 			/* page become full: move on to next page */
433 			lmNextPage(log);
434 
435 			bp = (struct lbuf *) log->bp;
436 			lp = (struct logpage *) bp->l_ldata;
437 			dstoffset = LOGPHDRSIZE;
438 
439 			srclen -= nbytes;
440 			src += nbytes;
441 		}
442 
443 		/*
444 		 * move log vector descriptor
445 		 */
446 		len += 4;
447 		lvd = (struct lvd *) ((caddr_t) lp + dstoffset);
448 		lvd->offset = cpu_to_le16(lv->offset);
449 		lvd->length = cpu_to_le16(lv->length);
450 		dstoffset += 4;
451 		jfs_info("lmWriteRecord: lv offset:%d length:%d",
452 			 lv->offset, lv->length);
453 	}
454 
455 	if ((i = linelock->next)) {
456 		linelock = (struct linelock *) lid_to_tlock(i);
457 		goto moveData;
458 	}
459 
460 	/*
461 	 *	move log record descriptor
462 	 */
463       moveLrd:
464 	lrd->length = cpu_to_le16(len);
465 
466 	src = (caddr_t) lrd;
467 	srclen = LOGRDSIZE;
468 
469 	while (srclen > 0) {
470 		freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
471 		nbytes = min(freespace, srclen);
472 		dst = (caddr_t) lp + dstoffset;
473 		memcpy(dst, src, nbytes);
474 
475 		dstoffset += nbytes;
476 		srclen -= nbytes;
477 
478 		/* are there more to move than freespace of page ? */
479 		if (srclen)
480 			goto pageFull;
481 
482 		/*
483 		 * end of log record descriptor
484 		 */
485 
486 		/* update last log record eor */
487 		log->eor = dstoffset;
488 		bp->l_eor = dstoffset;
489 		lsn = (log->page << L2LOGPSIZE) + dstoffset;
490 
491 		if (lrd->type & cpu_to_le16(LOG_COMMIT)) {
492 			tblk->clsn = lsn;
493 			jfs_info("wr: tclsn:0x%x, beor:0x%x", tblk->clsn,
494 				 bp->l_eor);
495 
496 			INCREMENT(lmStat.commit);	/* # of commit */
497 
498 			/*
499 			 * enqueue tblock for group commit:
500 			 *
501 			 * enqueue tblock of non-trivial/synchronous COMMIT
502 			 * at tail of group commit queue
503 			 * (trivial/asynchronous COMMITs are ignored by
504 			 * group commit.)
505 			 */
506 			LOGGC_LOCK(log);
507 
508 			/* init tblock gc state */
509 			tblk->flag = tblkGC_QUEUE;
510 			tblk->bp = log->bp;
511 			tblk->pn = log->page;
512 			tblk->eor = log->eor;
513 
514 			/* enqueue transaction to commit queue */
515 			list_add_tail(&tblk->cqueue, &log->cqueue);
516 
517 			LOGGC_UNLOCK(log);
518 		}
519 
520 		jfs_info("lmWriteRecord: lrd:0x%04x bp:0x%p pn:%d eor:0x%x",
521 			le16_to_cpu(lrd->type), log->bp, log->page, dstoffset);
522 
523 		/* page not full ? */
524 		if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
525 			return lsn;
526 
527 	      pageFull:
528 		/* page become full: move on to next page */
529 		lmNextPage(log);
530 
531 		bp = (struct lbuf *) log->bp;
532 		lp = (struct logpage *) bp->l_ldata;
533 		dstoffset = LOGPHDRSIZE;
534 		src += nbytes;
535 	}
536 
537 	return lsn;
538 }
539 
540 
541 /*
542  * NAME:	lmNextPage()
543  *
544  * FUNCTION:	write current page and allocate next page.
545  *
546  * PARAMETER:	log
547  *
548  * RETURN:	0
549  *
550  * serialization: LOG_LOCK() held on entry/exit
551  */
lmNextPage(struct jfs_log * log)552 static int lmNextPage(struct jfs_log * log)
553 {
554 	struct logpage *lp;
555 	int lspn;		/* log sequence page number */
556 	int pn;			/* current page number */
557 	struct lbuf *bp;
558 	struct lbuf *nextbp;
559 	struct tblock *tblk;
560 
561 	/* get current log page number and log sequence page number */
562 	pn = log->page;
563 	bp = log->bp;
564 	lp = (struct logpage *) bp->l_ldata;
565 	lspn = le32_to_cpu(lp->h.page);
566 
567 	LOGGC_LOCK(log);
568 
569 	/*
570 	 *	write or queue the full page at the tail of write queue
571 	 */
572 	/* get the tail tblk on commit queue */
573 	if (list_empty(&log->cqueue))
574 		tblk = NULL;
575 	else
576 		tblk = list_entry(log->cqueue.prev, struct tblock, cqueue);
577 
578 	/* every tblk who has COMMIT record on the current page,
579 	 * and has not been committed, must be on commit queue
580 	 * since tblk is queued at commit queueu at the time
581 	 * of writing its COMMIT record on the page before
582 	 * page becomes full (even though the tblk thread
583 	 * who wrote COMMIT record may have been suspended
584 	 * currently);
585 	 */
586 
587 	/* is page bound with outstanding tail tblk ? */
588 	if (tblk && tblk->pn == pn) {
589 		/* mark tblk for end-of-page */
590 		tblk->flag |= tblkGC_EOP;
591 
592 		if (log->cflag & logGC_PAGEOUT) {
593 			/* if page is not already on write queue,
594 			 * just enqueue (no lbmWRITE to prevent redrive)
595 			 * buffer to wqueue to ensure correct serial order
596 			 * of the pages since log pages will be added
597 			 * continuously
598 			 */
599 			if (bp->l_wqnext == NULL)
600 				lbmWrite(log, bp, 0, 0);
601 		} else {
602 			/*
603 			 * No current GC leader, initiate group commit
604 			 */
605 			log->cflag |= logGC_PAGEOUT;
606 			lmGCwrite(log, 0);
607 		}
608 	}
609 	/* page is not bound with outstanding tblk:
610 	 * init write or mark it to be redriven (lbmWRITE)
611 	 */
612 	else {
613 		/* finalize the page */
614 		bp->l_ceor = bp->l_eor;
615 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
616 		lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE, 0);
617 	}
618 	LOGGC_UNLOCK(log);
619 
620 	/*
621 	 *	allocate/initialize next page
622 	 */
623 	/* if log wraps, the first data page of log is 2
624 	 * (0 never used, 1 is superblock).
625 	 */
626 	log->page = (pn == log->size - 1) ? 2 : pn + 1;
627 	log->eor = LOGPHDRSIZE;	/* ? valid page empty/full at logRedo() */
628 
629 	/* allocate/initialize next log page buffer */
630 	nextbp = lbmAllocate(log, log->page);
631 	nextbp->l_eor = log->eor;
632 	log->bp = nextbp;
633 
634 	/* initialize next log page */
635 	lp = (struct logpage *) nextbp->l_ldata;
636 	lp->h.page = lp->t.page = cpu_to_le32(lspn + 1);
637 	lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
638 
639 	return 0;
640 }
641 
642 
643 /*
644  * NAME:	lmGroupCommit()
645  *
646  * FUNCTION:	group commit
647  *	initiate pageout of the pages with COMMIT in the order of
648  *	page number - redrive pageout of the page at the head of
649  *	pageout queue until full page has been written.
650  *
651  * RETURN:
652  *
653  * NOTE:
654  *	LOGGC_LOCK serializes log group commit queue, and
655  *	transaction blocks on the commit queue.
656  *	N.B. LOG_LOCK is NOT held during lmGroupCommit().
657  */
lmGroupCommit(struct jfs_log * log,struct tblock * tblk)658 int lmGroupCommit(struct jfs_log * log, struct tblock * tblk)
659 {
660 	int rc = 0;
661 
662 	LOGGC_LOCK(log);
663 
664 	/* group committed already ? */
665 	if (tblk->flag & tblkGC_COMMITTED) {
666 		if (tblk->flag & tblkGC_ERROR)
667 			rc = -EIO;
668 
669 		LOGGC_UNLOCK(log);
670 		return rc;
671 	}
672 	jfs_info("lmGroup Commit: tblk = 0x%p, gcrtc = %d", tblk, log->gcrtc);
673 
674 	if (tblk->xflag & COMMIT_LAZY)
675 		tblk->flag |= tblkGC_LAZY;
676 
677 	if ((!(log->cflag & logGC_PAGEOUT)) && (!list_empty(&log->cqueue)) &&
678 	    (!(tblk->xflag & COMMIT_LAZY) || test_bit(log_FLUSH, &log->flag)
679 	     || jfs_tlocks_low)) {
680 		/*
681 		 * No pageout in progress
682 		 *
683 		 * start group commit as its group leader.
684 		 */
685 		log->cflag |= logGC_PAGEOUT;
686 
687 		lmGCwrite(log, 0);
688 	}
689 
690 	if (tblk->xflag & COMMIT_LAZY) {
691 		/*
692 		 * Lazy transactions can leave now
693 		 */
694 		LOGGC_UNLOCK(log);
695 		return 0;
696 	}
697 
698 	/* lmGCwrite gives up LOGGC_LOCK, check again */
699 
700 	if (tblk->flag & tblkGC_COMMITTED) {
701 		if (tblk->flag & tblkGC_ERROR)
702 			rc = -EIO;
703 
704 		LOGGC_UNLOCK(log);
705 		return rc;
706 	}
707 
708 	/* upcount transaction waiting for completion
709 	 */
710 	log->gcrtc++;
711 	tblk->flag |= tblkGC_READY;
712 
713 	__SLEEP_COND(tblk->gcwait, (tblk->flag & tblkGC_COMMITTED),
714 		     LOGGC_LOCK(log), LOGGC_UNLOCK(log));
715 
716 	/* removed from commit queue */
717 	if (tblk->flag & tblkGC_ERROR)
718 		rc = -EIO;
719 
720 	LOGGC_UNLOCK(log);
721 	return rc;
722 }
723 
724 /*
725  * NAME:	lmGCwrite()
726  *
727  * FUNCTION:	group commit write
728  *	initiate write of log page, building a group of all transactions
729  *	with commit records on that page.
730  *
731  * RETURN:	None
732  *
733  * NOTE:
734  *	LOGGC_LOCK must be held by caller.
735  *	N.B. LOG_LOCK is NOT held during lmGroupCommit().
736  */
lmGCwrite(struct jfs_log * log,int cant_write)737 static void lmGCwrite(struct jfs_log * log, int cant_write)
738 {
739 	struct lbuf *bp;
740 	struct logpage *lp;
741 	int gcpn;		/* group commit page number */
742 	struct tblock *tblk;
743 	struct tblock *xtblk = NULL;
744 
745 	/*
746 	 * build the commit group of a log page
747 	 *
748 	 * scan commit queue and make a commit group of all
749 	 * transactions with COMMIT records on the same log page.
750 	 */
751 	/* get the head tblk on the commit queue */
752 	gcpn = list_entry(log->cqueue.next, struct tblock, cqueue)->pn;
753 
754 	list_for_each_entry(tblk, &log->cqueue, cqueue) {
755 		if (tblk->pn != gcpn)
756 			break;
757 
758 		xtblk = tblk;
759 
760 		/* state transition: (QUEUE, READY) -> COMMIT */
761 		tblk->flag |= tblkGC_COMMIT;
762 	}
763 	tblk = xtblk;		/* last tblk of the page */
764 
765 	/*
766 	 * pageout to commit transactions on the log page.
767 	 */
768 	bp = (struct lbuf *) tblk->bp;
769 	lp = (struct logpage *) bp->l_ldata;
770 	/* is page already full ? */
771 	if (tblk->flag & tblkGC_EOP) {
772 		/* mark page to free at end of group commit of the page */
773 		tblk->flag &= ~tblkGC_EOP;
774 		tblk->flag |= tblkGC_FREE;
775 		bp->l_ceor = bp->l_eor;
776 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
777 		lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmGC,
778 			 cant_write);
779 		INCREMENT(lmStat.full_page);
780 	}
781 	/* page is not yet full */
782 	else {
783 		bp->l_ceor = tblk->eor;	/* ? bp->l_ceor = bp->l_eor; */
784 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
785 		lbmWrite(log, bp, lbmWRITE | lbmGC, cant_write);
786 		INCREMENT(lmStat.partial_page);
787 	}
788 }
789 
790 /*
791  * NAME:	lmPostGC()
792  *
793  * FUNCTION:	group commit post-processing
794  *	Processes transactions after their commit records have been written
795  *	to disk, redriving log I/O if necessary.
796  *
797  * RETURN:	None
798  *
799  * NOTE:
800  *	This routine is called a interrupt time by lbmIODone
801  */
lmPostGC(struct lbuf * bp)802 static void lmPostGC(struct lbuf * bp)
803 {
804 	unsigned long flags;
805 	struct jfs_log *log = bp->l_log;
806 	struct logpage *lp;
807 	struct tblock *tblk, *temp;
808 
809 	//LOGGC_LOCK(log);
810 	spin_lock_irqsave(&log->gclock, flags);
811 	/*
812 	 * current pageout of group commit completed.
813 	 *
814 	 * remove/wakeup transactions from commit queue who were
815 	 * group committed with the current log page
816 	 */
817 	list_for_each_entry_safe(tblk, temp, &log->cqueue, cqueue) {
818 		if (!(tblk->flag & tblkGC_COMMIT))
819 			break;
820 		/* if transaction was marked GC_COMMIT then
821 		 * it has been shipped in the current pageout
822 		 * and made it to disk - it is committed.
823 		 */
824 
825 		if (bp->l_flag & lbmERROR)
826 			tblk->flag |= tblkGC_ERROR;
827 
828 		/* remove it from the commit queue */
829 		list_del(&tblk->cqueue);
830 		tblk->flag &= ~tblkGC_QUEUE;
831 
832 		if (tblk == log->flush_tblk) {
833 			/* we can stop flushing the log now */
834 			clear_bit(log_FLUSH, &log->flag);
835 			log->flush_tblk = NULL;
836 		}
837 
838 		jfs_info("lmPostGC: tblk = 0x%p, flag = 0x%x", tblk,
839 			 tblk->flag);
840 
841 		if (!(tblk->xflag & COMMIT_FORCE))
842 			/*
843 			 * Hand tblk over to lazy commit thread
844 			 */
845 			txLazyUnlock(tblk);
846 		else {
847 			/* state transition: COMMIT -> COMMITTED */
848 			tblk->flag |= tblkGC_COMMITTED;
849 
850 			if (tblk->flag & tblkGC_READY)
851 				log->gcrtc--;
852 
853 			LOGGC_WAKEUP(tblk);
854 		}
855 
856 		/* was page full before pageout ?
857 		 * (and this is the last tblk bound with the page)
858 		 */
859 		if (tblk->flag & tblkGC_FREE)
860 			lbmFree(bp);
861 		/* did page become full after pageout ?
862 		 * (and this is the last tblk bound with the page)
863 		 */
864 		else if (tblk->flag & tblkGC_EOP) {
865 			/* finalize the page */
866 			lp = (struct logpage *) bp->l_ldata;
867 			bp->l_ceor = bp->l_eor;
868 			lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
869 			jfs_info("lmPostGC: calling lbmWrite");
870 			lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE,
871 				 1);
872 		}
873 
874 	}
875 
876 	/* are there any transactions who have entered lnGroupCommit()
877 	 * (whose COMMITs are after that of the last log page written.
878 	 * They are waiting for new group commit (above at (SLEEP 1))
879 	 * or lazy transactions are on a full (queued) log page,
880 	 * select the latest ready transaction as new group leader and
881 	 * wake her up to lead her group.
882 	 */
883 	if ((!list_empty(&log->cqueue)) &&
884 	    ((log->gcrtc > 0) || (tblk->bp->l_wqnext != NULL) ||
885 	     test_bit(log_FLUSH, &log->flag) || jfs_tlocks_low))
886 		/*
887 		 * Call lmGCwrite with new group leader
888 		 */
889 		lmGCwrite(log, 1);
890 
891 	/* no transaction are ready yet (transactions are only just
892 	 * queued (GC_QUEUE) and not entered for group commit yet).
893 	 * the first transaction entering group commit
894 	 * will elect herself as new group leader.
895 	 */
896 	else
897 		log->cflag &= ~logGC_PAGEOUT;
898 
899 	//LOGGC_UNLOCK(log);
900 	spin_unlock_irqrestore(&log->gclock, flags);
901 	return;
902 }
903 
904 /*
905  * NAME:	lmLogSync()
906  *
907  * FUNCTION:	write log SYNCPT record for specified log
908  *	if new sync address is available
909  *	(normally the case if sync() is executed by back-ground
910  *	process).
911  *	calculate new value of i_nextsync which determines when
912  *	this code is called again.
913  *
914  * PARAMETERS:	log	- log structure
915  *		hard_sync - 1 to force all metadata to be written
916  *
917  * RETURN:	0
918  *
919  * serialization: LOG_LOCK() held on entry/exit
920  */
lmLogSync(struct jfs_log * log,int hard_sync)921 static int lmLogSync(struct jfs_log * log, int hard_sync)
922 {
923 	int logsize;
924 	int written;		/* written since last syncpt */
925 	int free;		/* free space left available */
926 	int delta;		/* additional delta to write normally */
927 	int more;		/* additional write granted */
928 	struct lrd lrd;
929 	int lsn;
930 	struct logsyncblk *lp;
931 	unsigned long flags;
932 
933 	/* push dirty metapages out to disk */
934 	if (hard_sync)
935 		write_special_inodes(log, filemap_fdatawrite);
936 	else
937 		write_special_inodes(log, filemap_flush);
938 
939 	/*
940 	 *	forward syncpt
941 	 */
942 	/* if last sync is same as last syncpt,
943 	 * invoke sync point forward processing to update sync.
944 	 */
945 
946 	if (log->sync == log->syncpt) {
947 		LOGSYNC_LOCK(log, flags);
948 		if (list_empty(&log->synclist))
949 			log->sync = log->lsn;
950 		else {
951 			lp = list_entry(log->synclist.next,
952 					struct logsyncblk, synclist);
953 			log->sync = lp->lsn;
954 		}
955 		LOGSYNC_UNLOCK(log, flags);
956 
957 	}
958 
959 	/* if sync is different from last syncpt,
960 	 * write a SYNCPT record with syncpt = sync.
961 	 * reset syncpt = sync
962 	 */
963 	if (log->sync != log->syncpt) {
964 		lrd.logtid = 0;
965 		lrd.backchain = 0;
966 		lrd.type = cpu_to_le16(LOG_SYNCPT);
967 		lrd.length = 0;
968 		lrd.log.syncpt.sync = cpu_to_le32(log->sync);
969 		lsn = lmWriteRecord(log, NULL, &lrd, NULL);
970 
971 		log->syncpt = log->sync;
972 	} else
973 		lsn = log->lsn;
974 
975 	/*
976 	 *	setup next syncpt trigger (SWAG)
977 	 */
978 	logsize = log->logsize;
979 
980 	logdiff(written, lsn, log);
981 	free = logsize - written;
982 	delta = LOGSYNC_DELTA(logsize);
983 	more = min(free / 2, delta);
984 	if (more < 2 * LOGPSIZE) {
985 		jfs_warn("\n ... Log Wrap ... Log Wrap ... Log Wrap ...\n");
986 		/*
987 		 *	log wrapping
988 		 *
989 		 * option 1 - panic ? No.!
990 		 * option 2 - shutdown file systems
991 		 *	      associated with log ?
992 		 * option 3 - extend log ?
993 		 * option 4 - second chance
994 		 *
995 		 * mark log wrapped, and continue.
996 		 * when all active transactions are completed,
997 		 * mark log valid for recovery.
998 		 * if crashed during invalid state, log state
999 		 * implies invalid log, forcing fsck().
1000 		 */
1001 		/* mark log state log wrap in log superblock */
1002 		/* log->state = LOGWRAP; */
1003 
1004 		/* reset sync point computation */
1005 		log->syncpt = log->sync = lsn;
1006 		log->nextsync = delta;
1007 	} else
1008 		/* next syncpt trigger = written + more */
1009 		log->nextsync = written + more;
1010 
1011 	/* if number of bytes written from last sync point is more
1012 	 * than 1/4 of the log size, stop new transactions from
1013 	 * starting until all current transactions are completed
1014 	 * by setting syncbarrier flag.
1015 	 */
1016 	if (!test_bit(log_SYNCBARRIER, &log->flag) &&
1017 	    (written > LOGSYNC_BARRIER(logsize)) && log->active) {
1018 		set_bit(log_SYNCBARRIER, &log->flag);
1019 		jfs_info("log barrier on: lsn=0x%x syncpt=0x%x", lsn,
1020 			 log->syncpt);
1021 		/*
1022 		 * We may have to initiate group commit
1023 		 */
1024 		jfs_flush_journal(log, 0);
1025 	}
1026 
1027 	return lsn;
1028 }
1029 
1030 /*
1031  * NAME:	jfs_syncpt
1032  *
1033  * FUNCTION:	write log SYNCPT record for specified log
1034  *
1035  * PARAMETERS:	log	  - log structure
1036  *		hard_sync - set to 1 to force metadata to be written
1037  */
jfs_syncpt(struct jfs_log * log,int hard_sync)1038 void jfs_syncpt(struct jfs_log *log, int hard_sync)
1039 {	LOG_LOCK(log);
1040 	if (!test_bit(log_QUIESCE, &log->flag))
1041 		lmLogSync(log, hard_sync);
1042 	LOG_UNLOCK(log);
1043 }
1044 
1045 /*
1046  * NAME:	lmLogOpen()
1047  *
1048  * FUNCTION:	open the log on first open;
1049  *	insert filesystem in the active list of the log.
1050  *
1051  * PARAMETER:	ipmnt	- file system mount inode
1052  *		iplog	- log inode (out)
1053  *
1054  * RETURN:
1055  *
1056  * serialization:
1057  */
lmLogOpen(struct super_block * sb)1058 int lmLogOpen(struct super_block *sb)
1059 {
1060 	int rc;
1061 	struct block_device *bdev;
1062 	struct jfs_log *log;
1063 	struct jfs_sb_info *sbi = JFS_SBI(sb);
1064 
1065 	if (sbi->flag & JFS_NOINTEGRITY)
1066 		return open_dummy_log(sb);
1067 
1068 	if (sbi->mntflag & JFS_INLINELOG)
1069 		return open_inline_log(sb);
1070 
1071 	mutex_lock(&jfs_log_mutex);
1072 	list_for_each_entry(log, &jfs_external_logs, journal_list) {
1073 		if (log->bdev->bd_dev == sbi->logdev) {
1074 			if (!uuid_equal(&log->uuid, &sbi->loguuid)) {
1075 				jfs_warn("wrong uuid on JFS journal");
1076 				mutex_unlock(&jfs_log_mutex);
1077 				return -EINVAL;
1078 			}
1079 			/*
1080 			 * add file system to log active file system list
1081 			 */
1082 			if ((rc = lmLogFileSystem(log, sbi, 1))) {
1083 				mutex_unlock(&jfs_log_mutex);
1084 				return rc;
1085 			}
1086 			goto journal_found;
1087 		}
1088 	}
1089 
1090 	if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL))) {
1091 		mutex_unlock(&jfs_log_mutex);
1092 		return -ENOMEM;
1093 	}
1094 	INIT_LIST_HEAD(&log->sb_list);
1095 	init_waitqueue_head(&log->syncwait);
1096 
1097 	/*
1098 	 *	external log as separate logical volume
1099 	 *
1100 	 * file systems to log may have n-to-1 relationship;
1101 	 */
1102 
1103 	bdev = blkdev_get_by_dev(sbi->logdev, BLK_OPEN_READ | BLK_OPEN_WRITE,
1104 				 log, NULL);
1105 	if (IS_ERR(bdev)) {
1106 		rc = PTR_ERR(bdev);
1107 		goto free;
1108 	}
1109 
1110 	log->bdev = bdev;
1111 	uuid_copy(&log->uuid, &sbi->loguuid);
1112 
1113 	/*
1114 	 * initialize log:
1115 	 */
1116 	if ((rc = lmLogInit(log)))
1117 		goto close;
1118 
1119 	list_add(&log->journal_list, &jfs_external_logs);
1120 
1121 	/*
1122 	 * add file system to log active file system list
1123 	 */
1124 	if ((rc = lmLogFileSystem(log, sbi, 1)))
1125 		goto shutdown;
1126 
1127 journal_found:
1128 	LOG_LOCK(log);
1129 	list_add(&sbi->log_list, &log->sb_list);
1130 	sbi->log = log;
1131 	LOG_UNLOCK(log);
1132 
1133 	mutex_unlock(&jfs_log_mutex);
1134 	return 0;
1135 
1136 	/*
1137 	 *	unwind on error
1138 	 */
1139       shutdown:		/* unwind lbmLogInit() */
1140 	list_del(&log->journal_list);
1141 	lbmLogShutdown(log);
1142 
1143       close:		/* close external log device */
1144 	blkdev_put(bdev, log);
1145 
1146       free:		/* free log descriptor */
1147 	mutex_unlock(&jfs_log_mutex);
1148 	kfree(log);
1149 
1150 	jfs_warn("lmLogOpen: exit(%d)", rc);
1151 	return rc;
1152 }
1153 
open_inline_log(struct super_block * sb)1154 static int open_inline_log(struct super_block *sb)
1155 {
1156 	struct jfs_log *log;
1157 	int rc;
1158 
1159 	if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL)))
1160 		return -ENOMEM;
1161 	INIT_LIST_HEAD(&log->sb_list);
1162 	init_waitqueue_head(&log->syncwait);
1163 
1164 	set_bit(log_INLINELOG, &log->flag);
1165 	log->bdev = sb->s_bdev;
1166 	log->base = addressPXD(&JFS_SBI(sb)->logpxd);
1167 	log->size = lengthPXD(&JFS_SBI(sb)->logpxd) >>
1168 	    (L2LOGPSIZE - sb->s_blocksize_bits);
1169 	log->l2bsize = sb->s_blocksize_bits;
1170 	ASSERT(L2LOGPSIZE >= sb->s_blocksize_bits);
1171 
1172 	/*
1173 	 * initialize log.
1174 	 */
1175 	if ((rc = lmLogInit(log))) {
1176 		kfree(log);
1177 		jfs_warn("lmLogOpen: exit(%d)", rc);
1178 		return rc;
1179 	}
1180 
1181 	list_add(&JFS_SBI(sb)->log_list, &log->sb_list);
1182 	JFS_SBI(sb)->log = log;
1183 
1184 	return rc;
1185 }
1186 
open_dummy_log(struct super_block * sb)1187 static int open_dummy_log(struct super_block *sb)
1188 {
1189 	int rc;
1190 
1191 	mutex_lock(&jfs_log_mutex);
1192 	if (!dummy_log) {
1193 		dummy_log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL);
1194 		if (!dummy_log) {
1195 			mutex_unlock(&jfs_log_mutex);
1196 			return -ENOMEM;
1197 		}
1198 		INIT_LIST_HEAD(&dummy_log->sb_list);
1199 		init_waitqueue_head(&dummy_log->syncwait);
1200 		dummy_log->no_integrity = 1;
1201 		/* Make up some stuff */
1202 		dummy_log->base = 0;
1203 		dummy_log->size = 1024;
1204 		rc = lmLogInit(dummy_log);
1205 		if (rc) {
1206 			kfree(dummy_log);
1207 			dummy_log = NULL;
1208 			mutex_unlock(&jfs_log_mutex);
1209 			return rc;
1210 		}
1211 	}
1212 
1213 	LOG_LOCK(dummy_log);
1214 	list_add(&JFS_SBI(sb)->log_list, &dummy_log->sb_list);
1215 	JFS_SBI(sb)->log = dummy_log;
1216 	LOG_UNLOCK(dummy_log);
1217 	mutex_unlock(&jfs_log_mutex);
1218 
1219 	return 0;
1220 }
1221 
1222 /*
1223  * NAME:	lmLogInit()
1224  *
1225  * FUNCTION:	log initialization at first log open.
1226  *
1227  *	logredo() (or logformat()) should have been run previously.
1228  *	initialize the log from log superblock.
1229  *	set the log state in the superblock to LOGMOUNT and
1230  *	write SYNCPT log record.
1231  *
1232  * PARAMETER:	log	- log structure
1233  *
1234  * RETURN:	0	- if ok
1235  *		-EINVAL	- bad log magic number or superblock dirty
1236  *		error returned from logwait()
1237  *
1238  * serialization: single first open thread
1239  */
lmLogInit(struct jfs_log * log)1240 int lmLogInit(struct jfs_log * log)
1241 {
1242 	int rc = 0;
1243 	struct lrd lrd;
1244 	struct logsuper *logsuper;
1245 	struct lbuf *bpsuper;
1246 	struct lbuf *bp;
1247 	struct logpage *lp;
1248 	int lsn = 0;
1249 
1250 	jfs_info("lmLogInit: log:0x%p", log);
1251 
1252 	/* initialize the group commit serialization lock */
1253 	LOGGC_LOCK_INIT(log);
1254 
1255 	/* allocate/initialize the log write serialization lock */
1256 	LOG_LOCK_INIT(log);
1257 
1258 	LOGSYNC_LOCK_INIT(log);
1259 
1260 	INIT_LIST_HEAD(&log->synclist);
1261 
1262 	INIT_LIST_HEAD(&log->cqueue);
1263 	log->flush_tblk = NULL;
1264 
1265 	log->count = 0;
1266 
1267 	/*
1268 	 * initialize log i/o
1269 	 */
1270 	if ((rc = lbmLogInit(log)))
1271 		return rc;
1272 
1273 	if (!test_bit(log_INLINELOG, &log->flag))
1274 		log->l2bsize = L2LOGPSIZE;
1275 
1276 	/* check for disabled journaling to disk */
1277 	if (log->no_integrity) {
1278 		/*
1279 		 * Journal pages will still be filled.  When the time comes
1280 		 * to actually do the I/O, the write is not done, and the
1281 		 * endio routine is called directly.
1282 		 */
1283 		bp = lbmAllocate(log , 0);
1284 		log->bp = bp;
1285 		bp->l_pn = bp->l_eor = 0;
1286 	} else {
1287 		/*
1288 		 * validate log superblock
1289 		 */
1290 		if ((rc = lbmRead(log, 1, &bpsuper)))
1291 			goto errout10;
1292 
1293 		logsuper = (struct logsuper *) bpsuper->l_ldata;
1294 
1295 		if (logsuper->magic != cpu_to_le32(LOGMAGIC)) {
1296 			jfs_warn("*** Log Format Error ! ***");
1297 			rc = -EINVAL;
1298 			goto errout20;
1299 		}
1300 
1301 		/* logredo() should have been run successfully. */
1302 		if (logsuper->state != cpu_to_le32(LOGREDONE)) {
1303 			jfs_warn("*** Log Is Dirty ! ***");
1304 			rc = -EINVAL;
1305 			goto errout20;
1306 		}
1307 
1308 		/* initialize log from log superblock */
1309 		if (test_bit(log_INLINELOG,&log->flag)) {
1310 			if (log->size != le32_to_cpu(logsuper->size)) {
1311 				rc = -EINVAL;
1312 				goto errout20;
1313 			}
1314 			jfs_info("lmLogInit: inline log:0x%p base:0x%Lx size:0x%x",
1315 				 log, (unsigned long long)log->base, log->size);
1316 		} else {
1317 			if (!uuid_equal(&logsuper->uuid, &log->uuid)) {
1318 				jfs_warn("wrong uuid on JFS log device");
1319 				rc = -EINVAL;
1320 				goto errout20;
1321 			}
1322 			log->size = le32_to_cpu(logsuper->size);
1323 			log->l2bsize = le32_to_cpu(logsuper->l2bsize);
1324 			jfs_info("lmLogInit: external log:0x%p base:0x%Lx size:0x%x",
1325 				 log, (unsigned long long)log->base, log->size);
1326 		}
1327 
1328 		log->page = le32_to_cpu(logsuper->end) / LOGPSIZE;
1329 		log->eor = le32_to_cpu(logsuper->end) - (LOGPSIZE * log->page);
1330 
1331 		/*
1332 		 * initialize for log append write mode
1333 		 */
1334 		/* establish current/end-of-log page/buffer */
1335 		if ((rc = lbmRead(log, log->page, &bp)))
1336 			goto errout20;
1337 
1338 		lp = (struct logpage *) bp->l_ldata;
1339 
1340 		jfs_info("lmLogInit: lsn:0x%x page:%d eor:%d:%d",
1341 			 le32_to_cpu(logsuper->end), log->page, log->eor,
1342 			 le16_to_cpu(lp->h.eor));
1343 
1344 		log->bp = bp;
1345 		bp->l_pn = log->page;
1346 		bp->l_eor = log->eor;
1347 
1348 		/* if current page is full, move on to next page */
1349 		if (log->eor >= LOGPSIZE - LOGPTLRSIZE)
1350 			lmNextPage(log);
1351 
1352 		/*
1353 		 * initialize log syncpoint
1354 		 */
1355 		/*
1356 		 * write the first SYNCPT record with syncpoint = 0
1357 		 * (i.e., log redo up to HERE !);
1358 		 * remove current page from lbm write queue at end of pageout
1359 		 * (to write log superblock update), but do not release to
1360 		 * freelist;
1361 		 */
1362 		lrd.logtid = 0;
1363 		lrd.backchain = 0;
1364 		lrd.type = cpu_to_le16(LOG_SYNCPT);
1365 		lrd.length = 0;
1366 		lrd.log.syncpt.sync = 0;
1367 		lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1368 		bp = log->bp;
1369 		bp->l_ceor = bp->l_eor;
1370 		lp = (struct logpage *) bp->l_ldata;
1371 		lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1372 		lbmWrite(log, bp, lbmWRITE | lbmSYNC, 0);
1373 		if ((rc = lbmIOWait(bp, 0)))
1374 			goto errout30;
1375 
1376 		/*
1377 		 * update/write superblock
1378 		 */
1379 		logsuper->state = cpu_to_le32(LOGMOUNT);
1380 		log->serial = le32_to_cpu(logsuper->serial) + 1;
1381 		logsuper->serial = cpu_to_le32(log->serial);
1382 		lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1383 		if ((rc = lbmIOWait(bpsuper, lbmFREE)))
1384 			goto errout30;
1385 	}
1386 
1387 	/* initialize logsync parameters */
1388 	log->logsize = (log->size - 2) << L2LOGPSIZE;
1389 	log->lsn = lsn;
1390 	log->syncpt = lsn;
1391 	log->sync = log->syncpt;
1392 	log->nextsync = LOGSYNC_DELTA(log->logsize);
1393 
1394 	jfs_info("lmLogInit: lsn:0x%x syncpt:0x%x sync:0x%x",
1395 		 log->lsn, log->syncpt, log->sync);
1396 
1397 	/*
1398 	 * initialize for lazy/group commit
1399 	 */
1400 	log->clsn = lsn;
1401 
1402 	return 0;
1403 
1404 	/*
1405 	 *	unwind on error
1406 	 */
1407       errout30:		/* release log page */
1408 	log->wqueue = NULL;
1409 	bp->l_wqnext = NULL;
1410 	lbmFree(bp);
1411 
1412       errout20:		/* release log superblock */
1413 	lbmFree(bpsuper);
1414 
1415       errout10:		/* unwind lbmLogInit() */
1416 	lbmLogShutdown(log);
1417 
1418 	jfs_warn("lmLogInit: exit(%d)", rc);
1419 	return rc;
1420 }
1421 
1422 
1423 /*
1424  * NAME:	lmLogClose()
1425  *
1426  * FUNCTION:	remove file system <ipmnt> from active list of log <iplog>
1427  *		and close it on last close.
1428  *
1429  * PARAMETER:	sb	- superblock
1430  *
1431  * RETURN:	errors from subroutines
1432  *
1433  * serialization:
1434  */
lmLogClose(struct super_block * sb)1435 int lmLogClose(struct super_block *sb)
1436 {
1437 	struct jfs_sb_info *sbi = JFS_SBI(sb);
1438 	struct jfs_log *log = sbi->log;
1439 	struct block_device *bdev;
1440 	int rc = 0;
1441 
1442 	jfs_info("lmLogClose: log:0x%p", log);
1443 
1444 	mutex_lock(&jfs_log_mutex);
1445 	LOG_LOCK(log);
1446 	list_del(&sbi->log_list);
1447 	LOG_UNLOCK(log);
1448 	sbi->log = NULL;
1449 
1450 	/*
1451 	 * We need to make sure all of the "written" metapages
1452 	 * actually make it to disk
1453 	 */
1454 	sync_blockdev(sb->s_bdev);
1455 
1456 	if (test_bit(log_INLINELOG, &log->flag)) {
1457 		/*
1458 		 *	in-line log in host file system
1459 		 */
1460 		rc = lmLogShutdown(log);
1461 		kfree(log);
1462 		goto out;
1463 	}
1464 
1465 	if (!log->no_integrity)
1466 		lmLogFileSystem(log, sbi, 0);
1467 
1468 	if (!list_empty(&log->sb_list))
1469 		goto out;
1470 
1471 	/*
1472 	 * TODO: ensure that the dummy_log is in a state to allow
1473 	 * lbmLogShutdown to deallocate all the buffers and call
1474 	 * kfree against dummy_log.  For now, leave dummy_log & its
1475 	 * buffers in memory, and resuse if another no-integrity mount
1476 	 * is requested.
1477 	 */
1478 	if (log->no_integrity)
1479 		goto out;
1480 
1481 	/*
1482 	 *	external log as separate logical volume
1483 	 */
1484 	list_del(&log->journal_list);
1485 	bdev = log->bdev;
1486 	rc = lmLogShutdown(log);
1487 
1488 	blkdev_put(bdev, log);
1489 
1490 	kfree(log);
1491 
1492       out:
1493 	mutex_unlock(&jfs_log_mutex);
1494 	jfs_info("lmLogClose: exit(%d)", rc);
1495 	return rc;
1496 }
1497 
1498 
1499 /*
1500  * NAME:	jfs_flush_journal()
1501  *
1502  * FUNCTION:	initiate write of any outstanding transactions to the journal
1503  *		and optionally wait until they are all written to disk
1504  *
1505  *		wait == 0  flush until latest txn is committed, don't wait
1506  *		wait == 1  flush until latest txn is committed, wait
1507  *		wait > 1   flush until all txn's are complete, wait
1508  */
jfs_flush_journal(struct jfs_log * log,int wait)1509 void jfs_flush_journal(struct jfs_log *log, int wait)
1510 {
1511 	int i;
1512 	struct tblock *target = NULL;
1513 
1514 	/* jfs_write_inode may call us during read-only mount */
1515 	if (!log)
1516 		return;
1517 
1518 	jfs_info("jfs_flush_journal: log:0x%p wait=%d", log, wait);
1519 
1520 	LOGGC_LOCK(log);
1521 
1522 	if (!list_empty(&log->cqueue)) {
1523 		/*
1524 		 * This ensures that we will keep writing to the journal as long
1525 		 * as there are unwritten commit records
1526 		 */
1527 		target = list_entry(log->cqueue.prev, struct tblock, cqueue);
1528 
1529 		if (test_bit(log_FLUSH, &log->flag)) {
1530 			/*
1531 			 * We're already flushing.
1532 			 * if flush_tblk is NULL, we are flushing everything,
1533 			 * so leave it that way.  Otherwise, update it to the
1534 			 * latest transaction
1535 			 */
1536 			if (log->flush_tblk)
1537 				log->flush_tblk = target;
1538 		} else {
1539 			/* Only flush until latest transaction is committed */
1540 			log->flush_tblk = target;
1541 			set_bit(log_FLUSH, &log->flag);
1542 
1543 			/*
1544 			 * Initiate I/O on outstanding transactions
1545 			 */
1546 			if (!(log->cflag & logGC_PAGEOUT)) {
1547 				log->cflag |= logGC_PAGEOUT;
1548 				lmGCwrite(log, 0);
1549 			}
1550 		}
1551 	}
1552 	if ((wait > 1) || test_bit(log_SYNCBARRIER, &log->flag)) {
1553 		/* Flush until all activity complete */
1554 		set_bit(log_FLUSH, &log->flag);
1555 		log->flush_tblk = NULL;
1556 	}
1557 
1558 	if (wait && target && !(target->flag & tblkGC_COMMITTED)) {
1559 		DECLARE_WAITQUEUE(__wait, current);
1560 
1561 		add_wait_queue(&target->gcwait, &__wait);
1562 		set_current_state(TASK_UNINTERRUPTIBLE);
1563 		LOGGC_UNLOCK(log);
1564 		schedule();
1565 		LOGGC_LOCK(log);
1566 		remove_wait_queue(&target->gcwait, &__wait);
1567 	}
1568 	LOGGC_UNLOCK(log);
1569 
1570 	if (wait < 2)
1571 		return;
1572 
1573 	write_special_inodes(log, filemap_fdatawrite);
1574 
1575 	/*
1576 	 * If there was recent activity, we may need to wait
1577 	 * for the lazycommit thread to catch up
1578 	 */
1579 	if ((!list_empty(&log->cqueue)) || !list_empty(&log->synclist)) {
1580 		for (i = 0; i < 200; i++) {	/* Too much? */
1581 			msleep(250);
1582 			write_special_inodes(log, filemap_fdatawrite);
1583 			if (list_empty(&log->cqueue) &&
1584 			    list_empty(&log->synclist))
1585 				break;
1586 		}
1587 	}
1588 	assert(list_empty(&log->cqueue));
1589 
1590 #ifdef CONFIG_JFS_DEBUG
1591 	if (!list_empty(&log->synclist)) {
1592 		struct logsyncblk *lp;
1593 
1594 		printk(KERN_ERR "jfs_flush_journal: synclist not empty\n");
1595 		list_for_each_entry(lp, &log->synclist, synclist) {
1596 			if (lp->xflag & COMMIT_PAGE) {
1597 				struct metapage *mp = (struct metapage *)lp;
1598 				print_hex_dump(KERN_ERR, "metapage: ",
1599 					       DUMP_PREFIX_ADDRESS, 16, 4,
1600 					       mp, sizeof(struct metapage), 0);
1601 				print_hex_dump(KERN_ERR, "page: ",
1602 					       DUMP_PREFIX_ADDRESS, 16,
1603 					       sizeof(long), mp->page,
1604 					       sizeof(struct page), 0);
1605 			} else
1606 				print_hex_dump(KERN_ERR, "tblock:",
1607 					       DUMP_PREFIX_ADDRESS, 16, 4,
1608 					       lp, sizeof(struct tblock), 0);
1609 		}
1610 	}
1611 #else
1612 	WARN_ON(!list_empty(&log->synclist));
1613 #endif
1614 	clear_bit(log_FLUSH, &log->flag);
1615 }
1616 
1617 /*
1618  * NAME:	lmLogShutdown()
1619  *
1620  * FUNCTION:	log shutdown at last LogClose().
1621  *
1622  *		write log syncpt record.
1623  *		update super block to set redone flag to 0.
1624  *
1625  * PARAMETER:	log	- log inode
1626  *
1627  * RETURN:	0	- success
1628  *
1629  * serialization: single last close thread
1630  */
lmLogShutdown(struct jfs_log * log)1631 int lmLogShutdown(struct jfs_log * log)
1632 {
1633 	int rc;
1634 	struct lrd lrd;
1635 	int lsn;
1636 	struct logsuper *logsuper;
1637 	struct lbuf *bpsuper;
1638 	struct lbuf *bp;
1639 	struct logpage *lp;
1640 
1641 	jfs_info("lmLogShutdown: log:0x%p", log);
1642 
1643 	jfs_flush_journal(log, 2);
1644 
1645 	/*
1646 	 * write the last SYNCPT record with syncpoint = 0
1647 	 * (i.e., log redo up to HERE !)
1648 	 */
1649 	lrd.logtid = 0;
1650 	lrd.backchain = 0;
1651 	lrd.type = cpu_to_le16(LOG_SYNCPT);
1652 	lrd.length = 0;
1653 	lrd.log.syncpt.sync = 0;
1654 
1655 	lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1656 	bp = log->bp;
1657 	lp = (struct logpage *) bp->l_ldata;
1658 	lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1659 	lbmWrite(log, log->bp, lbmWRITE | lbmRELEASE | lbmSYNC, 0);
1660 	lbmIOWait(log->bp, lbmFREE);
1661 	log->bp = NULL;
1662 
1663 	/*
1664 	 * synchronous update log superblock
1665 	 * mark log state as shutdown cleanly
1666 	 * (i.e., Log does not need to be replayed).
1667 	 */
1668 	if ((rc = lbmRead(log, 1, &bpsuper)))
1669 		goto out;
1670 
1671 	logsuper = (struct logsuper *) bpsuper->l_ldata;
1672 	logsuper->state = cpu_to_le32(LOGREDONE);
1673 	logsuper->end = cpu_to_le32(lsn);
1674 	lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1675 	rc = lbmIOWait(bpsuper, lbmFREE);
1676 
1677 	jfs_info("lmLogShutdown: lsn:0x%x page:%d eor:%d",
1678 		 lsn, log->page, log->eor);
1679 
1680       out:
1681 	/*
1682 	 * shutdown per log i/o
1683 	 */
1684 	lbmLogShutdown(log);
1685 
1686 	if (rc) {
1687 		jfs_warn("lmLogShutdown: exit(%d)", rc);
1688 	}
1689 	return rc;
1690 }
1691 
1692 
1693 /*
1694  * NAME:	lmLogFileSystem()
1695  *
1696  * FUNCTION:	insert (<activate> = true)/remove (<activate> = false)
1697  *	file system into/from log active file system list.
1698  *
1699  * PARAMETE:	log	- pointer to logs inode.
1700  *		fsdev	- kdev_t of filesystem.
1701  *		serial	- pointer to returned log serial number
1702  *		activate - insert/remove device from active list.
1703  *
1704  * RETURN:	0	- success
1705  *		errors returned by vms_iowait().
1706  */
lmLogFileSystem(struct jfs_log * log,struct jfs_sb_info * sbi,int activate)1707 static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
1708 			   int activate)
1709 {
1710 	int rc = 0;
1711 	int i;
1712 	struct logsuper *logsuper;
1713 	struct lbuf *bpsuper;
1714 	uuid_t *uuid = &sbi->uuid;
1715 
1716 	/*
1717 	 * insert/remove file system device to log active file system list.
1718 	 */
1719 	if ((rc = lbmRead(log, 1, &bpsuper)))
1720 		return rc;
1721 
1722 	logsuper = (struct logsuper *) bpsuper->l_ldata;
1723 	if (activate) {
1724 		for (i = 0; i < MAX_ACTIVE; i++)
1725 			if (uuid_is_null(&logsuper->active[i].uuid)) {
1726 				uuid_copy(&logsuper->active[i].uuid, uuid);
1727 				sbi->aggregate = i;
1728 				break;
1729 			}
1730 		if (i == MAX_ACTIVE) {
1731 			jfs_warn("Too many file systems sharing journal!");
1732 			lbmFree(bpsuper);
1733 			return -EMFILE;	/* Is there a better rc? */
1734 		}
1735 	} else {
1736 		for (i = 0; i < MAX_ACTIVE; i++)
1737 			if (uuid_equal(&logsuper->active[i].uuid, uuid)) {
1738 				uuid_copy(&logsuper->active[i].uuid,
1739 					  &uuid_null);
1740 				break;
1741 			}
1742 		if (i == MAX_ACTIVE) {
1743 			jfs_warn("Somebody stomped on the journal!");
1744 			lbmFree(bpsuper);
1745 			return -EIO;
1746 		}
1747 
1748 	}
1749 
1750 	/*
1751 	 * synchronous write log superblock:
1752 	 *
1753 	 * write sidestream bypassing write queue:
1754 	 * at file system mount, log super block is updated for
1755 	 * activation of the file system before any log record
1756 	 * (MOUNT record) of the file system, and at file system
1757 	 * unmount, all meta data for the file system has been
1758 	 * flushed before log super block is updated for deactivation
1759 	 * of the file system.
1760 	 */
1761 	lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1762 	rc = lbmIOWait(bpsuper, lbmFREE);
1763 
1764 	return rc;
1765 }
1766 
1767 /*
1768  *		log buffer manager (lbm)
1769  *		------------------------
1770  *
1771  * special purpose buffer manager supporting log i/o requirements.
1772  *
1773  * per log write queue:
1774  * log pageout occurs in serial order by fifo write queue and
1775  * restricting to a single i/o in pregress at any one time.
1776  * a circular singly-linked list
1777  * (log->wrqueue points to the tail, and buffers are linked via
1778  * bp->wrqueue field), and
1779  * maintains log page in pageout ot waiting for pageout in serial pageout.
1780  */
1781 
1782 /*
1783  *	lbmLogInit()
1784  *
1785  * initialize per log I/O setup at lmLogInit()
1786  */
lbmLogInit(struct jfs_log * log)1787 static int lbmLogInit(struct jfs_log * log)
1788 {				/* log inode */
1789 	int i;
1790 	struct lbuf *lbuf;
1791 
1792 	jfs_info("lbmLogInit: log:0x%p", log);
1793 
1794 	/* initialize current buffer cursor */
1795 	log->bp = NULL;
1796 
1797 	/* initialize log device write queue */
1798 	log->wqueue = NULL;
1799 
1800 	/*
1801 	 * Each log has its own buffer pages allocated to it.  These are
1802 	 * not managed by the page cache.  This ensures that a transaction
1803 	 * writing to the log does not block trying to allocate a page from
1804 	 * the page cache (for the log).  This would be bad, since page
1805 	 * allocation waits on the kswapd thread that may be committing inodes
1806 	 * which would cause log activity.  Was that clear?  I'm trying to
1807 	 * avoid deadlock here.
1808 	 */
1809 	init_waitqueue_head(&log->free_wait);
1810 
1811 	log->lbuf_free = NULL;
1812 
1813 	for (i = 0; i < LOGPAGES;) {
1814 		char *buffer;
1815 		uint offset;
1816 		struct page *page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1817 
1818 		if (!page)
1819 			goto error;
1820 		buffer = page_address(page);
1821 		for (offset = 0; offset < PAGE_SIZE; offset += LOGPSIZE) {
1822 			lbuf = kmalloc(sizeof(struct lbuf), GFP_KERNEL);
1823 			if (lbuf == NULL) {
1824 				if (offset == 0)
1825 					__free_page(page);
1826 				goto error;
1827 			}
1828 			if (offset) /* we already have one reference */
1829 				get_page(page);
1830 			lbuf->l_offset = offset;
1831 			lbuf->l_ldata = buffer + offset;
1832 			lbuf->l_page = page;
1833 			lbuf->l_log = log;
1834 			init_waitqueue_head(&lbuf->l_ioevent);
1835 
1836 			lbuf->l_freelist = log->lbuf_free;
1837 			log->lbuf_free = lbuf;
1838 			i++;
1839 		}
1840 	}
1841 
1842 	return (0);
1843 
1844       error:
1845 	lbmLogShutdown(log);
1846 	return -ENOMEM;
1847 }
1848 
1849 
1850 /*
1851  *	lbmLogShutdown()
1852  *
1853  * finalize per log I/O setup at lmLogShutdown()
1854  */
lbmLogShutdown(struct jfs_log * log)1855 static void lbmLogShutdown(struct jfs_log * log)
1856 {
1857 	struct lbuf *lbuf;
1858 
1859 	jfs_info("lbmLogShutdown: log:0x%p", log);
1860 
1861 	lbuf = log->lbuf_free;
1862 	while (lbuf) {
1863 		struct lbuf *next = lbuf->l_freelist;
1864 		__free_page(lbuf->l_page);
1865 		kfree(lbuf);
1866 		lbuf = next;
1867 	}
1868 }
1869 
1870 
1871 /*
1872  *	lbmAllocate()
1873  *
1874  * allocate an empty log buffer
1875  */
lbmAllocate(struct jfs_log * log,int pn)1876 static struct lbuf *lbmAllocate(struct jfs_log * log, int pn)
1877 {
1878 	struct lbuf *bp;
1879 	unsigned long flags;
1880 
1881 	/*
1882 	 * recycle from log buffer freelist if any
1883 	 */
1884 	LCACHE_LOCK(flags);
1885 	LCACHE_SLEEP_COND(log->free_wait, (bp = log->lbuf_free), flags);
1886 	log->lbuf_free = bp->l_freelist;
1887 	LCACHE_UNLOCK(flags);
1888 
1889 	bp->l_flag = 0;
1890 
1891 	bp->l_wqnext = NULL;
1892 	bp->l_freelist = NULL;
1893 
1894 	bp->l_pn = pn;
1895 	bp->l_blkno = log->base + (pn << (L2LOGPSIZE - log->l2bsize));
1896 	bp->l_ceor = 0;
1897 
1898 	return bp;
1899 }
1900 
1901 
1902 /*
1903  *	lbmFree()
1904  *
1905  * release a log buffer to freelist
1906  */
lbmFree(struct lbuf * bp)1907 static void lbmFree(struct lbuf * bp)
1908 {
1909 	unsigned long flags;
1910 
1911 	LCACHE_LOCK(flags);
1912 
1913 	lbmfree(bp);
1914 
1915 	LCACHE_UNLOCK(flags);
1916 }
1917 
lbmfree(struct lbuf * bp)1918 static void lbmfree(struct lbuf * bp)
1919 {
1920 	struct jfs_log *log = bp->l_log;
1921 
1922 	assert(bp->l_wqnext == NULL);
1923 
1924 	/*
1925 	 * return the buffer to head of freelist
1926 	 */
1927 	bp->l_freelist = log->lbuf_free;
1928 	log->lbuf_free = bp;
1929 
1930 	wake_up(&log->free_wait);
1931 	return;
1932 }
1933 
1934 
1935 /*
1936  * NAME:	lbmRedrive
1937  *
1938  * FUNCTION:	add a log buffer to the log redrive list
1939  *
1940  * PARAMETER:
1941  *	bp	- log buffer
1942  *
1943  * NOTES:
1944  *	Takes log_redrive_lock.
1945  */
lbmRedrive(struct lbuf * bp)1946 static inline void lbmRedrive(struct lbuf *bp)
1947 {
1948 	unsigned long flags;
1949 
1950 	spin_lock_irqsave(&log_redrive_lock, flags);
1951 	bp->l_redrive_next = log_redrive_list;
1952 	log_redrive_list = bp;
1953 	spin_unlock_irqrestore(&log_redrive_lock, flags);
1954 
1955 	wake_up_process(jfsIOthread);
1956 }
1957 
1958 
1959 /*
1960  *	lbmRead()
1961  */
lbmRead(struct jfs_log * log,int pn,struct lbuf ** bpp)1962 static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
1963 {
1964 	struct bio *bio;
1965 	struct lbuf *bp;
1966 
1967 	/*
1968 	 * allocate a log buffer
1969 	 */
1970 	*bpp = bp = lbmAllocate(log, pn);
1971 	jfs_info("lbmRead: bp:0x%p pn:0x%x", bp, pn);
1972 
1973 	bp->l_flag |= lbmREAD;
1974 
1975 	bio = bio_alloc(log->bdev, 1, REQ_OP_READ, GFP_NOFS);
1976 	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
1977 	__bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
1978 	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
1979 
1980 	bio->bi_end_io = lbmIODone;
1981 	bio->bi_private = bp;
1982 	/*check if journaling to disk has been disabled*/
1983 	if (log->no_integrity) {
1984 		bio->bi_iter.bi_size = 0;
1985 		lbmIODone(bio);
1986 	} else {
1987 		submit_bio(bio);
1988 	}
1989 
1990 	wait_event(bp->l_ioevent, (bp->l_flag != lbmREAD));
1991 
1992 	return 0;
1993 }
1994 
1995 
1996 /*
1997  *	lbmWrite()
1998  *
1999  * buffer at head of pageout queue stays after completion of
2000  * partial-page pageout and redriven by explicit initiation of
2001  * pageout by caller until full-page pageout is completed and
2002  * released.
2003  *
2004  * device driver i/o done redrives pageout of new buffer at
2005  * head of pageout queue when current buffer at head of pageout
2006  * queue is released at the completion of its full-page pageout.
2007  *
2008  * LOGGC_LOCK() serializes lbmWrite() by lmNextPage() and lmGroupCommit().
2009  * LCACHE_LOCK() serializes xflag between lbmWrite() and lbmIODone()
2010  */
lbmWrite(struct jfs_log * log,struct lbuf * bp,int flag,int cant_block)2011 static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag,
2012 		     int cant_block)
2013 {
2014 	struct lbuf *tail;
2015 	unsigned long flags;
2016 
2017 	jfs_info("lbmWrite: bp:0x%p flag:0x%x pn:0x%x", bp, flag, bp->l_pn);
2018 
2019 	/* map the logical block address to physical block address */
2020 	bp->l_blkno =
2021 	    log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2022 
2023 	LCACHE_LOCK(flags);		/* disable+lock */
2024 
2025 	/*
2026 	 * initialize buffer for device driver
2027 	 */
2028 	bp->l_flag = flag;
2029 
2030 	/*
2031 	 *	insert bp at tail of write queue associated with log
2032 	 *
2033 	 * (request is either for bp already/currently at head of queue
2034 	 * or new bp to be inserted at tail)
2035 	 */
2036 	tail = log->wqueue;
2037 
2038 	/* is buffer not already on write queue ? */
2039 	if (bp->l_wqnext == NULL) {
2040 		/* insert at tail of wqueue */
2041 		if (tail == NULL) {
2042 			log->wqueue = bp;
2043 			bp->l_wqnext = bp;
2044 		} else {
2045 			log->wqueue = bp;
2046 			bp->l_wqnext = tail->l_wqnext;
2047 			tail->l_wqnext = bp;
2048 		}
2049 
2050 		tail = bp;
2051 	}
2052 
2053 	/* is buffer at head of wqueue and for write ? */
2054 	if ((bp != tail->l_wqnext) || !(flag & lbmWRITE)) {
2055 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2056 		return;
2057 	}
2058 
2059 	LCACHE_UNLOCK(flags);	/* unlock+enable */
2060 
2061 	if (cant_block)
2062 		lbmRedrive(bp);
2063 	else if (flag & lbmSYNC)
2064 		lbmStartIO(bp);
2065 	else {
2066 		LOGGC_UNLOCK(log);
2067 		lbmStartIO(bp);
2068 		LOGGC_LOCK(log);
2069 	}
2070 }
2071 
2072 
2073 /*
2074  *	lbmDirectWrite()
2075  *
2076  * initiate pageout bypassing write queue for sidestream
2077  * (e.g., log superblock) write;
2078  */
lbmDirectWrite(struct jfs_log * log,struct lbuf * bp,int flag)2079 static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag)
2080 {
2081 	jfs_info("lbmDirectWrite: bp:0x%p flag:0x%x pn:0x%x",
2082 		 bp, flag, bp->l_pn);
2083 
2084 	/*
2085 	 * initialize buffer for device driver
2086 	 */
2087 	bp->l_flag = flag | lbmDIRECT;
2088 
2089 	/* map the logical block address to physical block address */
2090 	bp->l_blkno =
2091 	    log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2092 
2093 	/*
2094 	 *	initiate pageout of the page
2095 	 */
2096 	lbmStartIO(bp);
2097 }
2098 
2099 
2100 /*
2101  * NAME:	lbmStartIO()
2102  *
2103  * FUNCTION:	Interface to DD strategy routine
2104  *
2105  * RETURN:	none
2106  *
2107  * serialization: LCACHE_LOCK() is NOT held during log i/o;
2108  */
lbmStartIO(struct lbuf * bp)2109 static void lbmStartIO(struct lbuf * bp)
2110 {
2111 	struct bio *bio;
2112 	struct jfs_log *log = bp->l_log;
2113 
2114 	jfs_info("lbmStartIO");
2115 
2116 	bio = bio_alloc(log->bdev, 1, REQ_OP_WRITE | REQ_SYNC, GFP_NOFS);
2117 	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
2118 	__bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
2119 	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
2120 
2121 	bio->bi_end_io = lbmIODone;
2122 	bio->bi_private = bp;
2123 
2124 	/* check if journaling to disk has been disabled */
2125 	if (log->no_integrity) {
2126 		bio->bi_iter.bi_size = 0;
2127 		lbmIODone(bio);
2128 	} else {
2129 		submit_bio(bio);
2130 		INCREMENT(lmStat.submitted);
2131 	}
2132 }
2133 
2134 
2135 /*
2136  *	lbmIOWait()
2137  */
lbmIOWait(struct lbuf * bp,int flag)2138 static int lbmIOWait(struct lbuf * bp, int flag)
2139 {
2140 	unsigned long flags;
2141 	int rc = 0;
2142 
2143 	jfs_info("lbmIOWait1: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2144 
2145 	LCACHE_LOCK(flags);		/* disable+lock */
2146 
2147 	LCACHE_SLEEP_COND(bp->l_ioevent, (bp->l_flag & lbmDONE), flags);
2148 
2149 	rc = (bp->l_flag & lbmERROR) ? -EIO : 0;
2150 
2151 	if (flag & lbmFREE)
2152 		lbmfree(bp);
2153 
2154 	LCACHE_UNLOCK(flags);	/* unlock+enable */
2155 
2156 	jfs_info("lbmIOWait2: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2157 	return rc;
2158 }
2159 
2160 /*
2161  *	lbmIODone()
2162  *
2163  * executed at INTIODONE level
2164  */
lbmIODone(struct bio * bio)2165 static void lbmIODone(struct bio *bio)
2166 {
2167 	struct lbuf *bp = bio->bi_private;
2168 	struct lbuf *nextbp, *tail;
2169 	struct jfs_log *log;
2170 	unsigned long flags;
2171 
2172 	/*
2173 	 * get back jfs buffer bound to the i/o buffer
2174 	 */
2175 	jfs_info("lbmIODone: bp:0x%p flag:0x%x", bp, bp->l_flag);
2176 
2177 	LCACHE_LOCK(flags);		/* disable+lock */
2178 
2179 	bp->l_flag |= lbmDONE;
2180 
2181 	if (bio->bi_status) {
2182 		bp->l_flag |= lbmERROR;
2183 
2184 		jfs_err("lbmIODone: I/O error in JFS log");
2185 	}
2186 
2187 	bio_put(bio);
2188 
2189 	/*
2190 	 *	pagein completion
2191 	 */
2192 	if (bp->l_flag & lbmREAD) {
2193 		bp->l_flag &= ~lbmREAD;
2194 
2195 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2196 
2197 		/* wakeup I/O initiator */
2198 		LCACHE_WAKEUP(&bp->l_ioevent);
2199 
2200 		return;
2201 	}
2202 
2203 	/*
2204 	 *	pageout completion
2205 	 *
2206 	 * the bp at the head of write queue has completed pageout.
2207 	 *
2208 	 * if single-commit/full-page pageout, remove the current buffer
2209 	 * from head of pageout queue, and redrive pageout with
2210 	 * the new buffer at head of pageout queue;
2211 	 * otherwise, the partial-page pageout buffer stays at
2212 	 * the head of pageout queue to be redriven for pageout
2213 	 * by lmGroupCommit() until full-page pageout is completed.
2214 	 */
2215 	bp->l_flag &= ~lbmWRITE;
2216 	INCREMENT(lmStat.pagedone);
2217 
2218 	/* update committed lsn */
2219 	log = bp->l_log;
2220 	log->clsn = (bp->l_pn << L2LOGPSIZE) + bp->l_ceor;
2221 
2222 	if (bp->l_flag & lbmDIRECT) {
2223 		LCACHE_WAKEUP(&bp->l_ioevent);
2224 		LCACHE_UNLOCK(flags);
2225 		return;
2226 	}
2227 
2228 	tail = log->wqueue;
2229 
2230 	/* single element queue */
2231 	if (bp == tail) {
2232 		/* remove head buffer of full-page pageout
2233 		 * from log device write queue
2234 		 */
2235 		if (bp->l_flag & lbmRELEASE) {
2236 			log->wqueue = NULL;
2237 			bp->l_wqnext = NULL;
2238 		}
2239 	}
2240 	/* multi element queue */
2241 	else {
2242 		/* remove head buffer of full-page pageout
2243 		 * from log device write queue
2244 		 */
2245 		if (bp->l_flag & lbmRELEASE) {
2246 			nextbp = tail->l_wqnext = bp->l_wqnext;
2247 			bp->l_wqnext = NULL;
2248 
2249 			/*
2250 			 * redrive pageout of next page at head of write queue:
2251 			 * redrive next page without any bound tblk
2252 			 * (i.e., page w/o any COMMIT records), or
2253 			 * first page of new group commit which has been
2254 			 * queued after current page (subsequent pageout
2255 			 * is performed synchronously, except page without
2256 			 * any COMMITs) by lmGroupCommit() as indicated
2257 			 * by lbmWRITE flag;
2258 			 */
2259 			if (nextbp->l_flag & lbmWRITE) {
2260 				/*
2261 				 * We can't do the I/O at interrupt time.
2262 				 * The jfsIO thread can do it
2263 				 */
2264 				lbmRedrive(nextbp);
2265 			}
2266 		}
2267 	}
2268 
2269 	/*
2270 	 *	synchronous pageout:
2271 	 *
2272 	 * buffer has not necessarily been removed from write queue
2273 	 * (e.g., synchronous write of partial-page with COMMIT):
2274 	 * leave buffer for i/o initiator to dispose
2275 	 */
2276 	if (bp->l_flag & lbmSYNC) {
2277 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2278 
2279 		/* wakeup I/O initiator */
2280 		LCACHE_WAKEUP(&bp->l_ioevent);
2281 	}
2282 
2283 	/*
2284 	 *	Group Commit pageout:
2285 	 */
2286 	else if (bp->l_flag & lbmGC) {
2287 		LCACHE_UNLOCK(flags);
2288 		lmPostGC(bp);
2289 	}
2290 
2291 	/*
2292 	 *	asynchronous pageout:
2293 	 *
2294 	 * buffer must have been removed from write queue:
2295 	 * insert buffer at head of freelist where it can be recycled
2296 	 */
2297 	else {
2298 		assert(bp->l_flag & lbmRELEASE);
2299 		assert(bp->l_flag & lbmFREE);
2300 		lbmfree(bp);
2301 
2302 		LCACHE_UNLOCK(flags);	/* unlock+enable */
2303 	}
2304 }
2305 
jfsIOWait(void * arg)2306 int jfsIOWait(void *arg)
2307 {
2308 	struct lbuf *bp;
2309 
2310 	do {
2311 		spin_lock_irq(&log_redrive_lock);
2312 		while ((bp = log_redrive_list)) {
2313 			log_redrive_list = bp->l_redrive_next;
2314 			bp->l_redrive_next = NULL;
2315 			spin_unlock_irq(&log_redrive_lock);
2316 			lbmStartIO(bp);
2317 			spin_lock_irq(&log_redrive_lock);
2318 		}
2319 
2320 		if (freezing(current)) {
2321 			spin_unlock_irq(&log_redrive_lock);
2322 			try_to_freeze();
2323 		} else {
2324 			set_current_state(TASK_INTERRUPTIBLE);
2325 			spin_unlock_irq(&log_redrive_lock);
2326 			schedule();
2327 		}
2328 	} while (!kthread_should_stop());
2329 
2330 	jfs_info("jfsIOWait being killed!");
2331 	return 0;
2332 }
2333 
2334 /*
2335  * NAME:	lmLogFormat()/jfs_logform()
2336  *
2337  * FUNCTION:	format file system log
2338  *
2339  * PARAMETERS:
2340  *	log	- volume log
2341  *	logAddress - start address of log space in FS block
2342  *	logSize	- length of log space in FS block;
2343  *
2344  * RETURN:	0	- success
2345  *		-EIO	- i/o error
2346  *
2347  * XXX: We're synchronously writing one page at a time.  This needs to
2348  *	be improved by writing multiple pages at once.
2349  */
lmLogFormat(struct jfs_log * log,s64 logAddress,int logSize)2350 int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize)
2351 {
2352 	int rc = -EIO;
2353 	struct jfs_sb_info *sbi;
2354 	struct logsuper *logsuper;
2355 	struct logpage *lp;
2356 	int lspn;		/* log sequence page number */
2357 	struct lrd *lrd_ptr;
2358 	int npages = 0;
2359 	struct lbuf *bp;
2360 
2361 	jfs_info("lmLogFormat: logAddress:%Ld logSize:%d",
2362 		 (long long)logAddress, logSize);
2363 
2364 	sbi = list_entry(log->sb_list.next, struct jfs_sb_info, log_list);
2365 
2366 	/* allocate a log buffer */
2367 	bp = lbmAllocate(log, 1);
2368 
2369 	npages = logSize >> sbi->l2nbperpage;
2370 
2371 	/*
2372 	 *	log space:
2373 	 *
2374 	 * page 0 - reserved;
2375 	 * page 1 - log superblock;
2376 	 * page 2 - log data page: A SYNC log record is written
2377 	 *	    into this page at logform time;
2378 	 * pages 3-N - log data page: set to empty log data pages;
2379 	 */
2380 	/*
2381 	 *	init log superblock: log page 1
2382 	 */
2383 	logsuper = (struct logsuper *) bp->l_ldata;
2384 
2385 	logsuper->magic = cpu_to_le32(LOGMAGIC);
2386 	logsuper->version = cpu_to_le32(LOGVERSION);
2387 	logsuper->state = cpu_to_le32(LOGREDONE);
2388 	logsuper->flag = cpu_to_le32(sbi->mntflag);	/* ? */
2389 	logsuper->size = cpu_to_le32(npages);
2390 	logsuper->bsize = cpu_to_le32(sbi->bsize);
2391 	logsuper->l2bsize = cpu_to_le32(sbi->l2bsize);
2392 	logsuper->end = cpu_to_le32(2 * LOGPSIZE + LOGPHDRSIZE + LOGRDSIZE);
2393 
2394 	bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2395 	bp->l_blkno = logAddress + sbi->nbperpage;
2396 	lbmStartIO(bp);
2397 	if ((rc = lbmIOWait(bp, 0)))
2398 		goto exit;
2399 
2400 	/*
2401 	 *	init pages 2 to npages-1 as log data pages:
2402 	 *
2403 	 * log page sequence number (lpsn) initialization:
2404 	 *
2405 	 * pn:   0     1     2     3                 n-1
2406 	 *       +-----+-----+=====+=====+===.....===+=====+
2407 	 * lspn:             N-1   0     1           N-2
2408 	 *                   <--- N page circular file ---->
2409 	 *
2410 	 * the N (= npages-2) data pages of the log is maintained as
2411 	 * a circular file for the log records;
2412 	 * lpsn grows by 1 monotonically as each log page is written
2413 	 * to the circular file of the log;
2414 	 * and setLogpage() will not reset the page number even if
2415 	 * the eor is equal to LOGPHDRSIZE. In order for binary search
2416 	 * still work in find log end process, we have to simulate the
2417 	 * log wrap situation at the log format time.
2418 	 * The 1st log page written will have the highest lpsn. Then
2419 	 * the succeeding log pages will have ascending order of
2420 	 * the lspn starting from 0, ... (N-2)
2421 	 */
2422 	lp = (struct logpage *) bp->l_ldata;
2423 	/*
2424 	 * initialize 1st log page to be written: lpsn = N - 1,
2425 	 * write a SYNCPT log record is written to this page
2426 	 */
2427 	lp->h.page = lp->t.page = cpu_to_le32(npages - 3);
2428 	lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE + LOGRDSIZE);
2429 
2430 	lrd_ptr = (struct lrd *) &lp->data;
2431 	lrd_ptr->logtid = 0;
2432 	lrd_ptr->backchain = 0;
2433 	lrd_ptr->type = cpu_to_le16(LOG_SYNCPT);
2434 	lrd_ptr->length = 0;
2435 	lrd_ptr->log.syncpt.sync = 0;
2436 
2437 	bp->l_blkno += sbi->nbperpage;
2438 	bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2439 	lbmStartIO(bp);
2440 	if ((rc = lbmIOWait(bp, 0)))
2441 		goto exit;
2442 
2443 	/*
2444 	 *	initialize succeeding log pages: lpsn = 0, 1, ..., (N-2)
2445 	 */
2446 	for (lspn = 0; lspn < npages - 3; lspn++) {
2447 		lp->h.page = lp->t.page = cpu_to_le32(lspn);
2448 		lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
2449 
2450 		bp->l_blkno += sbi->nbperpage;
2451 		bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2452 		lbmStartIO(bp);
2453 		if ((rc = lbmIOWait(bp, 0)))
2454 			goto exit;
2455 	}
2456 
2457 	rc = 0;
2458 exit:
2459 	/*
2460 	 *	finalize log
2461 	 */
2462 	/* release the buffer */
2463 	lbmFree(bp);
2464 
2465 	return rc;
2466 }
2467 
2468 #ifdef CONFIG_JFS_STATISTICS
jfs_lmstats_proc_show(struct seq_file * m,void * v)2469 int jfs_lmstats_proc_show(struct seq_file *m, void *v)
2470 {
2471 	seq_printf(m,
2472 		       "JFS Logmgr stats\n"
2473 		       "================\n"
2474 		       "commits = %d\n"
2475 		       "writes submitted = %d\n"
2476 		       "writes completed = %d\n"
2477 		       "full pages submitted = %d\n"
2478 		       "partial pages submitted = %d\n",
2479 		       lmStat.commit,
2480 		       lmStat.submitted,
2481 		       lmStat.pagedone,
2482 		       lmStat.full_page,
2483 		       lmStat.partial_page);
2484 	return 0;
2485 }
2486 #endif /* CONFIG_JFS_STATISTICS */
2487