Loading...
1/*
2 * Copyright (C) International Business Machines Corp., 2000-2005
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#include <linux/fs.h>
21#include <linux/mm.h>
22#include <linux/module.h>
23#include <linux/bio.h>
24#include <linux/slab.h>
25#include <linux/init.h>
26#include <linux/buffer_head.h>
27#include <linux/mempool.h>
28#include <linux/seq_file.h>
29#include "jfs_incore.h"
30#include "jfs_superblock.h"
31#include "jfs_filsys.h"
32#include "jfs_metapage.h"
33#include "jfs_txnmgr.h"
34#include "jfs_debug.h"
35
36#ifdef CONFIG_JFS_STATISTICS
37static struct {
38 uint pagealloc; /* # of page allocations */
39 uint pagefree; /* # of page frees */
40 uint lockwait; /* # of sleeping lock_metapage() calls */
41} mpStat;
42#endif
43
44#define metapage_locked(mp) test_bit(META_locked, &(mp)->flag)
45#define trylock_metapage(mp) test_and_set_bit_lock(META_locked, &(mp)->flag)
46
47static inline void unlock_metapage(struct metapage *mp)
48{
49 clear_bit_unlock(META_locked, &mp->flag);
50 wake_up(&mp->wait);
51}
52
53static inline void __lock_metapage(struct metapage *mp)
54{
55 DECLARE_WAITQUEUE(wait, current);
56 INCREMENT(mpStat.lockwait);
57 add_wait_queue_exclusive(&mp->wait, &wait);
58 do {
59 set_current_state(TASK_UNINTERRUPTIBLE);
60 if (metapage_locked(mp)) {
61 unlock_page(mp->page);
62 io_schedule();
63 lock_page(mp->page);
64 }
65 } while (trylock_metapage(mp));
66 __set_current_state(TASK_RUNNING);
67 remove_wait_queue(&mp->wait, &wait);
68}
69
70/*
71 * Must have mp->page locked
72 */
73static inline void lock_metapage(struct metapage *mp)
74{
75 if (trylock_metapage(mp))
76 __lock_metapage(mp);
77}
78
79#define METAPOOL_MIN_PAGES 32
80static struct kmem_cache *metapage_cache;
81static mempool_t *metapage_mempool;
82
83#define MPS_PER_PAGE (PAGE_SIZE >> L2PSIZE)
84
85#if MPS_PER_PAGE > 1
86
87struct meta_anchor {
88 int mp_count;
89 atomic_t io_count;
90 struct metapage *mp[MPS_PER_PAGE];
91};
92#define mp_anchor(page) ((struct meta_anchor *)page_private(page))
93
94static inline struct metapage *page_to_mp(struct page *page, int offset)
95{
96 if (!PagePrivate(page))
97 return NULL;
98 return mp_anchor(page)->mp[offset >> L2PSIZE];
99}
100
101static inline int insert_metapage(struct page *page, struct metapage *mp)
102{
103 struct meta_anchor *a;
104 int index;
105 int l2mp_blocks; /* log2 blocks per metapage */
106
107 if (PagePrivate(page))
108 a = mp_anchor(page);
109 else {
110 a = kzalloc(sizeof(struct meta_anchor), GFP_NOFS);
111 if (!a)
112 return -ENOMEM;
113 set_page_private(page, (unsigned long)a);
114 SetPagePrivate(page);
115 kmap(page);
116 }
117
118 if (mp) {
119 l2mp_blocks = L2PSIZE - page->mapping->host->i_blkbits;
120 index = (mp->index >> l2mp_blocks) & (MPS_PER_PAGE - 1);
121 a->mp_count++;
122 a->mp[index] = mp;
123 }
124
125 return 0;
126}
127
128static inline void remove_metapage(struct page *page, struct metapage *mp)
129{
130 struct meta_anchor *a = mp_anchor(page);
131 int l2mp_blocks = L2PSIZE - page->mapping->host->i_blkbits;
132 int index;
133
134 index = (mp->index >> l2mp_blocks) & (MPS_PER_PAGE - 1);
135
136 BUG_ON(a->mp[index] != mp);
137
138 a->mp[index] = NULL;
139 if (--a->mp_count == 0) {
140 kfree(a);
141 set_page_private(page, 0);
142 ClearPagePrivate(page);
143 kunmap(page);
144 }
145}
146
147static inline void inc_io(struct page *page)
148{
149 atomic_inc(&mp_anchor(page)->io_count);
150}
151
152static inline void dec_io(struct page *page, void (*handler) (struct page *))
153{
154 if (atomic_dec_and_test(&mp_anchor(page)->io_count))
155 handler(page);
156}
157
158#else
159static inline struct metapage *page_to_mp(struct page *page, int offset)
160{
161 return PagePrivate(page) ? (struct metapage *)page_private(page) : NULL;
162}
163
164static inline int insert_metapage(struct page *page, struct metapage *mp)
165{
166 if (mp) {
167 set_page_private(page, (unsigned long)mp);
168 SetPagePrivate(page);
169 kmap(page);
170 }
171 return 0;
172}
173
174static inline void remove_metapage(struct page *page, struct metapage *mp)
175{
176 set_page_private(page, 0);
177 ClearPagePrivate(page);
178 kunmap(page);
179}
180
181#define inc_io(page) do {} while(0)
182#define dec_io(page, handler) handler(page)
183
184#endif
185
186static inline struct metapage *alloc_metapage(gfp_t gfp_mask)
187{
188 struct metapage *mp = mempool_alloc(metapage_mempool, gfp_mask);
189
190 if (mp) {
191 mp->lid = 0;
192 mp->lsn = 0;
193 mp->data = NULL;
194 mp->clsn = 0;
195 mp->log = NULL;
196 init_waitqueue_head(&mp->wait);
197 }
198 return mp;
199}
200
201static inline void free_metapage(struct metapage *mp)
202{
203 mempool_free(mp, metapage_mempool);
204}
205
206int __init metapage_init(void)
207{
208 /*
209 * Allocate the metapage structures
210 */
211 metapage_cache = kmem_cache_create("jfs_mp", sizeof(struct metapage),
212 0, 0, NULL);
213 if (metapage_cache == NULL)
214 return -ENOMEM;
215
216 metapage_mempool = mempool_create_slab_pool(METAPOOL_MIN_PAGES,
217 metapage_cache);
218
219 if (metapage_mempool == NULL) {
220 kmem_cache_destroy(metapage_cache);
221 return -ENOMEM;
222 }
223
224 return 0;
225}
226
227void metapage_exit(void)
228{
229 mempool_destroy(metapage_mempool);
230 kmem_cache_destroy(metapage_cache);
231}
232
233static inline void drop_metapage(struct page *page, struct metapage *mp)
234{
235 if (mp->count || mp->nohomeok || test_bit(META_dirty, &mp->flag) ||
236 test_bit(META_io, &mp->flag))
237 return;
238 remove_metapage(page, mp);
239 INCREMENT(mpStat.pagefree);
240 free_metapage(mp);
241}
242
243/*
244 * Metapage address space operations
245 */
246
247static sector_t metapage_get_blocks(struct inode *inode, sector_t lblock,
248 int *len)
249{
250 int rc = 0;
251 int xflag;
252 s64 xaddr;
253 sector_t file_blocks = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
254 inode->i_blkbits;
255
256 if (lblock >= file_blocks)
257 return 0;
258 if (lblock + *len > file_blocks)
259 *len = file_blocks - lblock;
260
261 if (inode->i_ino) {
262 rc = xtLookup(inode, (s64)lblock, *len, &xflag, &xaddr, len, 0);
263 if ((rc == 0) && *len)
264 lblock = (sector_t)xaddr;
265 else
266 lblock = 0;
267 } /* else no mapping */
268
269 return lblock;
270}
271
272static void last_read_complete(struct page *page)
273{
274 if (!PageError(page))
275 SetPageUptodate(page);
276 unlock_page(page);
277}
278
279static void metapage_read_end_io(struct bio *bio)
280{
281 struct page *page = bio->bi_private;
282
283 if (bio->bi_status) {
284 printk(KERN_ERR "metapage_read_end_io: I/O error\n");
285 SetPageError(page);
286 }
287
288 dec_io(page, last_read_complete);
289 bio_put(bio);
290}
291
292static void remove_from_logsync(struct metapage *mp)
293{
294 struct jfs_log *log = mp->log;
295 unsigned long flags;
296/*
297 * This can race. Recheck that log hasn't been set to null, and after
298 * acquiring logsync lock, recheck lsn
299 */
300 if (!log)
301 return;
302
303 LOGSYNC_LOCK(log, flags);
304 if (mp->lsn) {
305 mp->log = NULL;
306 mp->lsn = 0;
307 mp->clsn = 0;
308 log->count--;
309 list_del(&mp->synclist);
310 }
311 LOGSYNC_UNLOCK(log, flags);
312}
313
314static void last_write_complete(struct page *page)
315{
316 struct metapage *mp;
317 unsigned int offset;
318
319 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
320 mp = page_to_mp(page, offset);
321 if (mp && test_bit(META_io, &mp->flag)) {
322 if (mp->lsn)
323 remove_from_logsync(mp);
324 clear_bit(META_io, &mp->flag);
325 }
326 /*
327 * I'd like to call drop_metapage here, but I don't think it's
328 * safe unless I have the page locked
329 */
330 }
331 end_page_writeback(page);
332}
333
334static void metapage_write_end_io(struct bio *bio)
335{
336 struct page *page = bio->bi_private;
337
338 BUG_ON(!PagePrivate(page));
339
340 if (bio->bi_status) {
341 printk(KERN_ERR "metapage_write_end_io: I/O error\n");
342 SetPageError(page);
343 }
344 dec_io(page, last_write_complete);
345 bio_put(bio);
346}
347
348static int metapage_writepage(struct page *page, struct writeback_control *wbc)
349{
350 struct bio *bio = NULL;
351 int block_offset; /* block offset of mp within page */
352 struct inode *inode = page->mapping->host;
353 int blocks_per_mp = JFS_SBI(inode->i_sb)->nbperpage;
354 int len;
355 int xlen;
356 struct metapage *mp;
357 int redirty = 0;
358 sector_t lblock;
359 int nr_underway = 0;
360 sector_t pblock;
361 sector_t next_block = 0;
362 sector_t page_start;
363 unsigned long bio_bytes = 0;
364 unsigned long bio_offset = 0;
365 int offset;
366 int bad_blocks = 0;
367
368 page_start = (sector_t)page->index <<
369 (PAGE_SHIFT - inode->i_blkbits);
370 BUG_ON(!PageLocked(page));
371 BUG_ON(PageWriteback(page));
372 set_page_writeback(page);
373
374 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
375 mp = page_to_mp(page, offset);
376
377 if (!mp || !test_bit(META_dirty, &mp->flag))
378 continue;
379
380 if (mp->nohomeok && !test_bit(META_forcewrite, &mp->flag)) {
381 redirty = 1;
382 /*
383 * Make sure this page isn't blocked indefinitely.
384 * If the journal isn't undergoing I/O, push it
385 */
386 if (mp->log && !(mp->log->cflag & logGC_PAGEOUT))
387 jfs_flush_journal(mp->log, 0);
388 continue;
389 }
390
391 clear_bit(META_dirty, &mp->flag);
392 set_bit(META_io, &mp->flag);
393 block_offset = offset >> inode->i_blkbits;
394 lblock = page_start + block_offset;
395 if (bio) {
396 if (xlen && lblock == next_block) {
397 /* Contiguous, in memory & on disk */
398 len = min(xlen, blocks_per_mp);
399 xlen -= len;
400 bio_bytes += len << inode->i_blkbits;
401 continue;
402 }
403 /* Not contiguous */
404 if (bio_add_page(bio, page, bio_bytes, bio_offset) <
405 bio_bytes)
406 goto add_failed;
407 /*
408 * Increment counter before submitting i/o to keep
409 * count from hitting zero before we're through
410 */
411 inc_io(page);
412 if (!bio->bi_iter.bi_size)
413 goto dump_bio;
414 submit_bio(bio);
415 nr_underway++;
416 bio = NULL;
417 } else
418 inc_io(page);
419 xlen = (PAGE_SIZE - offset) >> inode->i_blkbits;
420 pblock = metapage_get_blocks(inode, lblock, &xlen);
421 if (!pblock) {
422 printk(KERN_ERR "JFS: metapage_get_blocks failed\n");
423 /*
424 * We already called inc_io(), but can't cancel it
425 * with dec_io() until we're done with the page
426 */
427 bad_blocks++;
428 continue;
429 }
430 len = min(xlen, (int)JFS_SBI(inode->i_sb)->nbperpage);
431
432 bio = bio_alloc(GFP_NOFS, 1);
433 bio_set_dev(bio, inode->i_sb->s_bdev);
434 bio->bi_iter.bi_sector = pblock << (inode->i_blkbits - 9);
435 bio->bi_end_io = metapage_write_end_io;
436 bio->bi_private = page;
437 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
438
439 /* Don't call bio_add_page yet, we may add to this vec */
440 bio_offset = offset;
441 bio_bytes = len << inode->i_blkbits;
442
443 xlen -= len;
444 next_block = lblock + len;
445 }
446 if (bio) {
447 if (bio_add_page(bio, page, bio_bytes, bio_offset) < bio_bytes)
448 goto add_failed;
449 if (!bio->bi_iter.bi_size)
450 goto dump_bio;
451
452 submit_bio(bio);
453 nr_underway++;
454 }
455 if (redirty)
456 redirty_page_for_writepage(wbc, page);
457
458 unlock_page(page);
459
460 if (bad_blocks)
461 goto err_out;
462
463 if (nr_underway == 0)
464 end_page_writeback(page);
465
466 return 0;
467add_failed:
468 /* We should never reach here, since we're only adding one vec */
469 printk(KERN_ERR "JFS: bio_add_page failed unexpectedly\n");
470 goto skip;
471dump_bio:
472 print_hex_dump(KERN_ERR, "JFS: dump of bio: ", DUMP_PREFIX_ADDRESS, 16,
473 4, bio, sizeof(*bio), 0);
474skip:
475 bio_put(bio);
476 unlock_page(page);
477 dec_io(page, last_write_complete);
478err_out:
479 while (bad_blocks--)
480 dec_io(page, last_write_complete);
481 return -EIO;
482}
483
484static int metapage_readpage(struct file *fp, struct page *page)
485{
486 struct inode *inode = page->mapping->host;
487 struct bio *bio = NULL;
488 int block_offset;
489 int blocks_per_page = PAGE_SIZE >> inode->i_blkbits;
490 sector_t page_start; /* address of page in fs blocks */
491 sector_t pblock;
492 int xlen;
493 unsigned int len;
494 int offset;
495
496 BUG_ON(!PageLocked(page));
497 page_start = (sector_t)page->index <<
498 (PAGE_SHIFT - inode->i_blkbits);
499
500 block_offset = 0;
501 while (block_offset < blocks_per_page) {
502 xlen = blocks_per_page - block_offset;
503 pblock = metapage_get_blocks(inode, page_start + block_offset,
504 &xlen);
505 if (pblock) {
506 if (!PagePrivate(page))
507 insert_metapage(page, NULL);
508 inc_io(page);
509 if (bio)
510 submit_bio(bio);
511
512 bio = bio_alloc(GFP_NOFS, 1);
513 bio_set_dev(bio, inode->i_sb->s_bdev);
514 bio->bi_iter.bi_sector =
515 pblock << (inode->i_blkbits - 9);
516 bio->bi_end_io = metapage_read_end_io;
517 bio->bi_private = page;
518 bio_set_op_attrs(bio, REQ_OP_READ, 0);
519 len = xlen << inode->i_blkbits;
520 offset = block_offset << inode->i_blkbits;
521 if (bio_add_page(bio, page, len, offset) < len)
522 goto add_failed;
523 block_offset += xlen;
524 } else
525 block_offset++;
526 }
527 if (bio)
528 submit_bio(bio);
529 else
530 unlock_page(page);
531
532 return 0;
533
534add_failed:
535 printk(KERN_ERR "JFS: bio_add_page failed unexpectedly\n");
536 bio_put(bio);
537 dec_io(page, last_read_complete);
538 return -EIO;
539}
540
541static int metapage_releasepage(struct page *page, gfp_t gfp_mask)
542{
543 struct metapage *mp;
544 int ret = 1;
545 int offset;
546
547 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
548 mp = page_to_mp(page, offset);
549
550 if (!mp)
551 continue;
552
553 jfs_info("metapage_releasepage: mp = 0x%p", mp);
554 if (mp->count || mp->nohomeok ||
555 test_bit(META_dirty, &mp->flag)) {
556 jfs_info("count = %ld, nohomeok = %d", mp->count,
557 mp->nohomeok);
558 ret = 0;
559 continue;
560 }
561 if (mp->lsn)
562 remove_from_logsync(mp);
563 remove_metapage(page, mp);
564 INCREMENT(mpStat.pagefree);
565 free_metapage(mp);
566 }
567 return ret;
568}
569
570static void metapage_invalidatepage(struct page *page, unsigned int offset,
571 unsigned int length)
572{
573 BUG_ON(offset || length < PAGE_SIZE);
574
575 BUG_ON(PageWriteback(page));
576
577 metapage_releasepage(page, 0);
578}
579
580const struct address_space_operations jfs_metapage_aops = {
581 .readpage = metapage_readpage,
582 .writepage = metapage_writepage,
583 .releasepage = metapage_releasepage,
584 .invalidatepage = metapage_invalidatepage,
585 .set_page_dirty = __set_page_dirty_nobuffers,
586};
587
588struct metapage *__get_metapage(struct inode *inode, unsigned long lblock,
589 unsigned int size, int absolute,
590 unsigned long new)
591{
592 int l2BlocksPerPage;
593 int l2bsize;
594 struct address_space *mapping;
595 struct metapage *mp = NULL;
596 struct page *page;
597 unsigned long page_index;
598 unsigned long page_offset;
599
600 jfs_info("__get_metapage: ino = %ld, lblock = 0x%lx, abs=%d",
601 inode->i_ino, lblock, absolute);
602
603 l2bsize = inode->i_blkbits;
604 l2BlocksPerPage = PAGE_SHIFT - l2bsize;
605 page_index = lblock >> l2BlocksPerPage;
606 page_offset = (lblock - (page_index << l2BlocksPerPage)) << l2bsize;
607 if ((page_offset + size) > PAGE_SIZE) {
608 jfs_err("MetaData crosses page boundary!!");
609 jfs_err("lblock = %lx, size = %d", lblock, size);
610 dump_stack();
611 return NULL;
612 }
613 if (absolute)
614 mapping = JFS_SBI(inode->i_sb)->direct_inode->i_mapping;
615 else {
616 /*
617 * If an nfs client tries to read an inode that is larger
618 * than any existing inodes, we may try to read past the
619 * end of the inode map
620 */
621 if ((lblock << inode->i_blkbits) >= inode->i_size)
622 return NULL;
623 mapping = inode->i_mapping;
624 }
625
626 if (new && (PSIZE == PAGE_SIZE)) {
627 page = grab_cache_page(mapping, page_index);
628 if (!page) {
629 jfs_err("grab_cache_page failed!");
630 return NULL;
631 }
632 SetPageUptodate(page);
633 } else {
634 page = read_mapping_page(mapping, page_index, NULL);
635 if (IS_ERR(page) || !PageUptodate(page)) {
636 jfs_err("read_mapping_page failed!");
637 return NULL;
638 }
639 lock_page(page);
640 }
641
642 mp = page_to_mp(page, page_offset);
643 if (mp) {
644 if (mp->logical_size != size) {
645 jfs_error(inode->i_sb,
646 "get_mp->logical_size != size\n");
647 jfs_err("logical_size = %d, size = %d",
648 mp->logical_size, size);
649 dump_stack();
650 goto unlock;
651 }
652 mp->count++;
653 lock_metapage(mp);
654 if (test_bit(META_discard, &mp->flag)) {
655 if (!new) {
656 jfs_error(inode->i_sb,
657 "using a discarded metapage\n");
658 discard_metapage(mp);
659 goto unlock;
660 }
661 clear_bit(META_discard, &mp->flag);
662 }
663 } else {
664 INCREMENT(mpStat.pagealloc);
665 mp = alloc_metapage(GFP_NOFS);
666 if (!mp)
667 goto unlock;
668 mp->page = page;
669 mp->sb = inode->i_sb;
670 mp->flag = 0;
671 mp->xflag = COMMIT_PAGE;
672 mp->count = 1;
673 mp->nohomeok = 0;
674 mp->logical_size = size;
675 mp->data = page_address(page) + page_offset;
676 mp->index = lblock;
677 if (unlikely(insert_metapage(page, mp))) {
678 free_metapage(mp);
679 goto unlock;
680 }
681 lock_metapage(mp);
682 }
683
684 if (new) {
685 jfs_info("zeroing mp = 0x%p", mp);
686 memset(mp->data, 0, PSIZE);
687 }
688
689 unlock_page(page);
690 jfs_info("__get_metapage: returning = 0x%p data = 0x%p", mp, mp->data);
691 return mp;
692
693unlock:
694 unlock_page(page);
695 return NULL;
696}
697
698void grab_metapage(struct metapage * mp)
699{
700 jfs_info("grab_metapage: mp = 0x%p", mp);
701 get_page(mp->page);
702 lock_page(mp->page);
703 mp->count++;
704 lock_metapage(mp);
705 unlock_page(mp->page);
706}
707
708void force_metapage(struct metapage *mp)
709{
710 struct page *page = mp->page;
711 jfs_info("force_metapage: mp = 0x%p", mp);
712 set_bit(META_forcewrite, &mp->flag);
713 clear_bit(META_sync, &mp->flag);
714 get_page(page);
715 lock_page(page);
716 set_page_dirty(page);
717 if (write_one_page(page))
718 jfs_error(mp->sb, "write_one_page() failed\n");
719 clear_bit(META_forcewrite, &mp->flag);
720 put_page(page);
721}
722
723void hold_metapage(struct metapage *mp)
724{
725 lock_page(mp->page);
726}
727
728void put_metapage(struct metapage *mp)
729{
730 if (mp->count || mp->nohomeok) {
731 /* Someone else will release this */
732 unlock_page(mp->page);
733 return;
734 }
735 get_page(mp->page);
736 mp->count++;
737 lock_metapage(mp);
738 unlock_page(mp->page);
739 release_metapage(mp);
740}
741
742void release_metapage(struct metapage * mp)
743{
744 struct page *page = mp->page;
745 jfs_info("release_metapage: mp = 0x%p, flag = 0x%lx", mp, mp->flag);
746
747 BUG_ON(!page);
748
749 lock_page(page);
750 unlock_metapage(mp);
751
752 assert(mp->count);
753 if (--mp->count || mp->nohomeok) {
754 unlock_page(page);
755 put_page(page);
756 return;
757 }
758
759 if (test_bit(META_dirty, &mp->flag)) {
760 set_page_dirty(page);
761 if (test_bit(META_sync, &mp->flag)) {
762 clear_bit(META_sync, &mp->flag);
763 if (write_one_page(page))
764 jfs_error(mp->sb, "write_one_page() failed\n");
765 lock_page(page); /* write_one_page unlocks the page */
766 }
767 } else if (mp->lsn) /* discard_metapage doesn't remove it */
768 remove_from_logsync(mp);
769
770 /* Try to keep metapages from using up too much memory */
771 drop_metapage(page, mp);
772
773 unlock_page(page);
774 put_page(page);
775}
776
777void __invalidate_metapages(struct inode *ip, s64 addr, int len)
778{
779 sector_t lblock;
780 int l2BlocksPerPage = PAGE_SHIFT - ip->i_blkbits;
781 int BlocksPerPage = 1 << l2BlocksPerPage;
782 /* All callers are interested in block device's mapping */
783 struct address_space *mapping =
784 JFS_SBI(ip->i_sb)->direct_inode->i_mapping;
785 struct metapage *mp;
786 struct page *page;
787 unsigned int offset;
788
789 /*
790 * Mark metapages to discard. They will eventually be
791 * released, but should not be written.
792 */
793 for (lblock = addr & ~(BlocksPerPage - 1); lblock < addr + len;
794 lblock += BlocksPerPage) {
795 page = find_lock_page(mapping, lblock >> l2BlocksPerPage);
796 if (!page)
797 continue;
798 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
799 mp = page_to_mp(page, offset);
800 if (!mp)
801 continue;
802 if (mp->index < addr)
803 continue;
804 if (mp->index >= addr + len)
805 break;
806
807 clear_bit(META_dirty, &mp->flag);
808 set_bit(META_discard, &mp->flag);
809 if (mp->lsn)
810 remove_from_logsync(mp);
811 }
812 unlock_page(page);
813 put_page(page);
814 }
815}
816
817#ifdef CONFIG_JFS_STATISTICS
818static int jfs_mpstat_proc_show(struct seq_file *m, void *v)
819{
820 seq_printf(m,
821 "JFS Metapage statistics\n"
822 "=======================\n"
823 "page allocations = %d\n"
824 "page frees = %d\n"
825 "lock waits = %d\n",
826 mpStat.pagealloc,
827 mpStat.pagefree,
828 mpStat.lockwait);
829 return 0;
830}
831
832static int jfs_mpstat_proc_open(struct inode *inode, struct file *file)
833{
834 return single_open(file, jfs_mpstat_proc_show, NULL);
835}
836
837const struct file_operations jfs_mpstat_proc_fops = {
838 .open = jfs_mpstat_proc_open,
839 .read = seq_read,
840 .llseek = seq_lseek,
841 .release = single_release,
842};
843#endif
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) International Business Machines Corp., 2000-2005
4 * Portions Copyright (C) Christoph Hellwig, 2001-2002
5 */
6
7#include <linux/blkdev.h>
8#include <linux/fs.h>
9#include <linux/mm.h>
10#include <linux/module.h>
11#include <linux/bio.h>
12#include <linux/slab.h>
13#include <linux/init.h>
14#include <linux/buffer_head.h>
15#include <linux/mempool.h>
16#include <linux/seq_file.h>
17#include <linux/writeback.h>
18#include "jfs_incore.h"
19#include "jfs_superblock.h"
20#include "jfs_filsys.h"
21#include "jfs_metapage.h"
22#include "jfs_txnmgr.h"
23#include "jfs_debug.h"
24
25#ifdef CONFIG_JFS_STATISTICS
26static struct {
27 uint pagealloc; /* # of page allocations */
28 uint pagefree; /* # of page frees */
29 uint lockwait; /* # of sleeping lock_metapage() calls */
30} mpStat;
31#endif
32
33#define metapage_locked(mp) test_bit(META_locked, &(mp)->flag)
34#define trylock_metapage(mp) test_and_set_bit_lock(META_locked, &(mp)->flag)
35
36static inline void unlock_metapage(struct metapage *mp)
37{
38 clear_bit_unlock(META_locked, &mp->flag);
39 wake_up(&mp->wait);
40}
41
42static inline void __lock_metapage(struct metapage *mp)
43{
44 DECLARE_WAITQUEUE(wait, current);
45 INCREMENT(mpStat.lockwait);
46 add_wait_queue_exclusive(&mp->wait, &wait);
47 do {
48 set_current_state(TASK_UNINTERRUPTIBLE);
49 if (metapage_locked(mp)) {
50 folio_unlock(mp->folio);
51 io_schedule();
52 folio_lock(mp->folio);
53 }
54 } while (trylock_metapage(mp));
55 __set_current_state(TASK_RUNNING);
56 remove_wait_queue(&mp->wait, &wait);
57}
58
59/*
60 * Must have mp->folio locked
61 */
62static inline void lock_metapage(struct metapage *mp)
63{
64 if (trylock_metapage(mp))
65 __lock_metapage(mp);
66}
67
68#define METAPOOL_MIN_PAGES 32
69static struct kmem_cache *metapage_cache;
70static mempool_t *metapage_mempool;
71
72#define MPS_PER_PAGE (PAGE_SIZE >> L2PSIZE)
73
74#if MPS_PER_PAGE > 1
75
76struct meta_anchor {
77 int mp_count;
78 atomic_t io_count;
79 blk_status_t status;
80 struct metapage *mp[MPS_PER_PAGE];
81};
82
83static inline struct metapage *folio_to_mp(struct folio *folio, int offset)
84{
85 struct meta_anchor *anchor = folio->private;
86
87 if (!anchor)
88 return NULL;
89 return anchor->mp[offset >> L2PSIZE];
90}
91
92static inline int insert_metapage(struct folio *folio, struct metapage *mp)
93{
94 struct meta_anchor *a;
95 int index;
96 int l2mp_blocks; /* log2 blocks per metapage */
97
98 a = folio->private;
99 if (!a) {
100 a = kzalloc(sizeof(struct meta_anchor), GFP_NOFS);
101 if (!a)
102 return -ENOMEM;
103 folio_attach_private(folio, a);
104 kmap(&folio->page);
105 }
106
107 if (mp) {
108 l2mp_blocks = L2PSIZE - folio->mapping->host->i_blkbits;
109 index = (mp->index >> l2mp_blocks) & (MPS_PER_PAGE - 1);
110 a->mp_count++;
111 a->mp[index] = mp;
112 }
113
114 return 0;
115}
116
117static inline void remove_metapage(struct folio *folio, struct metapage *mp)
118{
119 struct meta_anchor *a = folio->private;
120 int l2mp_blocks = L2PSIZE - folio->mapping->host->i_blkbits;
121 int index;
122
123 index = (mp->index >> l2mp_blocks) & (MPS_PER_PAGE - 1);
124
125 BUG_ON(a->mp[index] != mp);
126
127 a->mp[index] = NULL;
128 if (--a->mp_count == 0) {
129 kfree(a);
130 folio_detach_private(folio);
131 kunmap(&folio->page);
132 }
133}
134
135static inline void inc_io(struct folio *folio)
136{
137 struct meta_anchor *anchor = folio->private;
138
139 atomic_inc(&anchor->io_count);
140}
141
142static inline void dec_io(struct folio *folio, blk_status_t status,
143 void (*handler)(struct folio *, blk_status_t))
144{
145 struct meta_anchor *anchor = folio->private;
146
147 if (anchor->status == BLK_STS_OK)
148 anchor->status = status;
149
150 if (atomic_dec_and_test(&anchor->io_count))
151 handler(folio, anchor->status);
152}
153
154#else
155static inline struct metapage *folio_to_mp(struct folio *folio, int offset)
156{
157 return folio->private;
158}
159
160static inline int insert_metapage(struct folio *folio, struct metapage *mp)
161{
162 if (mp) {
163 folio_attach_private(folio, mp);
164 kmap(&folio->page);
165 }
166 return 0;
167}
168
169static inline void remove_metapage(struct folio *folio, struct metapage *mp)
170{
171 folio_detach_private(folio);
172 kunmap(&folio->page);
173}
174
175#define inc_io(folio) do {} while(0)
176#define dec_io(folio, status, handler) handler(folio, status)
177
178#endif
179
180static inline struct metapage *alloc_metapage(gfp_t gfp_mask)
181{
182 struct metapage *mp = mempool_alloc(metapage_mempool, gfp_mask);
183
184 if (mp) {
185 mp->lid = 0;
186 mp->lsn = 0;
187 mp->data = NULL;
188 mp->clsn = 0;
189 mp->log = NULL;
190 init_waitqueue_head(&mp->wait);
191 }
192 return mp;
193}
194
195static inline void free_metapage(struct metapage *mp)
196{
197 mempool_free(mp, metapage_mempool);
198}
199
200int __init metapage_init(void)
201{
202 /*
203 * Allocate the metapage structures
204 */
205 metapage_cache = kmem_cache_create("jfs_mp", sizeof(struct metapage),
206 0, 0, NULL);
207 if (metapage_cache == NULL)
208 return -ENOMEM;
209
210 metapage_mempool = mempool_create_slab_pool(METAPOOL_MIN_PAGES,
211 metapage_cache);
212
213 if (metapage_mempool == NULL) {
214 kmem_cache_destroy(metapage_cache);
215 return -ENOMEM;
216 }
217
218 return 0;
219}
220
221void metapage_exit(void)
222{
223 mempool_destroy(metapage_mempool);
224 kmem_cache_destroy(metapage_cache);
225}
226
227static inline void drop_metapage(struct folio *folio, struct metapage *mp)
228{
229 if (mp->count || mp->nohomeok || test_bit(META_dirty, &mp->flag) ||
230 test_bit(META_io, &mp->flag))
231 return;
232 remove_metapage(folio, mp);
233 INCREMENT(mpStat.pagefree);
234 free_metapage(mp);
235}
236
237/*
238 * Metapage address space operations
239 */
240
241static sector_t metapage_get_blocks(struct inode *inode, sector_t lblock,
242 int *len)
243{
244 int rc = 0;
245 int xflag;
246 s64 xaddr;
247 sector_t file_blocks = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
248 inode->i_blkbits;
249
250 if (lblock >= file_blocks)
251 return 0;
252 if (lblock + *len > file_blocks)
253 *len = file_blocks - lblock;
254
255 if (inode->i_ino) {
256 rc = xtLookup(inode, (s64)lblock, *len, &xflag, &xaddr, len, 0);
257 if ((rc == 0) && *len)
258 lblock = (sector_t)xaddr;
259 else
260 lblock = 0;
261 } /* else no mapping */
262
263 return lblock;
264}
265
266static void last_read_complete(struct folio *folio, blk_status_t status)
267{
268 if (status)
269 printk(KERN_ERR "Read error %d at %#llx\n", status,
270 folio_pos(folio));
271
272 folio_end_read(folio, status == 0);
273}
274
275static void metapage_read_end_io(struct bio *bio)
276{
277 struct folio *folio = bio->bi_private;
278
279 dec_io(folio, bio->bi_status, last_read_complete);
280 bio_put(bio);
281}
282
283static void remove_from_logsync(struct metapage *mp)
284{
285 struct jfs_log *log = mp->log;
286 unsigned long flags;
287/*
288 * This can race. Recheck that log hasn't been set to null, and after
289 * acquiring logsync lock, recheck lsn
290 */
291 if (!log)
292 return;
293
294 LOGSYNC_LOCK(log, flags);
295 if (mp->lsn) {
296 mp->log = NULL;
297 mp->lsn = 0;
298 mp->clsn = 0;
299 log->count--;
300 list_del(&mp->synclist);
301 }
302 LOGSYNC_UNLOCK(log, flags);
303}
304
305static void last_write_complete(struct folio *folio, blk_status_t status)
306{
307 struct metapage *mp;
308 unsigned int offset;
309
310 if (status) {
311 int err = blk_status_to_errno(status);
312 printk(KERN_ERR "metapage_write_end_io: I/O error\n");
313 mapping_set_error(folio->mapping, err);
314 }
315
316 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
317 mp = folio_to_mp(folio, offset);
318 if (mp && test_bit(META_io, &mp->flag)) {
319 if (mp->lsn)
320 remove_from_logsync(mp);
321 clear_bit(META_io, &mp->flag);
322 }
323 /*
324 * I'd like to call drop_metapage here, but I don't think it's
325 * safe unless I have the page locked
326 */
327 }
328 folio_end_writeback(folio);
329}
330
331static void metapage_write_end_io(struct bio *bio)
332{
333 struct folio *folio = bio->bi_private;
334
335 BUG_ON(!folio->private);
336
337 dec_io(folio, bio->bi_status, last_write_complete);
338 bio_put(bio);
339}
340
341static int metapage_write_folio(struct folio *folio,
342 struct writeback_control *wbc, void *unused)
343{
344 struct bio *bio = NULL;
345 int block_offset; /* block offset of mp within page */
346 struct inode *inode = folio->mapping->host;
347 int blocks_per_mp = JFS_SBI(inode->i_sb)->nbperpage;
348 int len;
349 int xlen;
350 struct metapage *mp;
351 int redirty = 0;
352 sector_t lblock;
353 int nr_underway = 0;
354 sector_t pblock;
355 sector_t next_block = 0;
356 sector_t page_start;
357 unsigned long bio_bytes = 0;
358 unsigned long bio_offset = 0;
359 int offset;
360 int bad_blocks = 0;
361
362 page_start = folio_pos(folio) >> inode->i_blkbits;
363 BUG_ON(!folio_test_locked(folio));
364 BUG_ON(folio_test_writeback(folio));
365 folio_start_writeback(folio);
366
367 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
368 mp = folio_to_mp(folio, offset);
369
370 if (!mp || !test_bit(META_dirty, &mp->flag))
371 continue;
372
373 if (mp->nohomeok && !test_bit(META_forcewrite, &mp->flag)) {
374 redirty = 1;
375 /*
376 * Make sure this page isn't blocked indefinitely.
377 * If the journal isn't undergoing I/O, push it
378 */
379 if (mp->log && !(mp->log->cflag & logGC_PAGEOUT))
380 jfs_flush_journal(mp->log, 0);
381 continue;
382 }
383
384 clear_bit(META_dirty, &mp->flag);
385 set_bit(META_io, &mp->flag);
386 block_offset = offset >> inode->i_blkbits;
387 lblock = page_start + block_offset;
388 if (bio) {
389 if (xlen && lblock == next_block) {
390 /* Contiguous, in memory & on disk */
391 len = min(xlen, blocks_per_mp);
392 xlen -= len;
393 bio_bytes += len << inode->i_blkbits;
394 continue;
395 }
396 /* Not contiguous */
397 bio_add_folio_nofail(bio, folio, bio_bytes, bio_offset);
398 /*
399 * Increment counter before submitting i/o to keep
400 * count from hitting zero before we're through
401 */
402 inc_io(folio);
403 if (!bio->bi_iter.bi_size)
404 goto dump_bio;
405 submit_bio(bio);
406 nr_underway++;
407 bio = NULL;
408 } else
409 inc_io(folio);
410 xlen = (folio_size(folio) - offset) >> inode->i_blkbits;
411 pblock = metapage_get_blocks(inode, lblock, &xlen);
412 if (!pblock) {
413 printk(KERN_ERR "JFS: metapage_get_blocks failed\n");
414 /*
415 * We already called inc_io(), but can't cancel it
416 * with dec_io() until we're done with the page
417 */
418 bad_blocks++;
419 continue;
420 }
421 len = min(xlen, (int)JFS_SBI(inode->i_sb)->nbperpage);
422
423 bio = bio_alloc(inode->i_sb->s_bdev, 1, REQ_OP_WRITE, GFP_NOFS);
424 bio->bi_iter.bi_sector = pblock << (inode->i_blkbits - 9);
425 bio->bi_end_io = metapage_write_end_io;
426 bio->bi_private = folio;
427
428 /* Don't call bio_add_page yet, we may add to this vec */
429 bio_offset = offset;
430 bio_bytes = len << inode->i_blkbits;
431
432 xlen -= len;
433 next_block = lblock + len;
434 }
435 if (bio) {
436 bio_add_folio_nofail(bio, folio, bio_bytes, bio_offset);
437 if (!bio->bi_iter.bi_size)
438 goto dump_bio;
439
440 submit_bio(bio);
441 nr_underway++;
442 }
443 if (redirty)
444 folio_redirty_for_writepage(wbc, folio);
445
446 folio_unlock(folio);
447
448 if (bad_blocks)
449 goto err_out;
450
451 if (nr_underway == 0)
452 folio_end_writeback(folio);
453
454 return 0;
455dump_bio:
456 print_hex_dump(KERN_ERR, "JFS: dump of bio: ", DUMP_PREFIX_ADDRESS, 16,
457 4, bio, sizeof(*bio), 0);
458 bio_put(bio);
459 folio_unlock(folio);
460 dec_io(folio, BLK_STS_OK, last_write_complete);
461err_out:
462 while (bad_blocks--)
463 dec_io(folio, BLK_STS_OK, last_write_complete);
464 return -EIO;
465}
466
467static int metapage_writepages(struct address_space *mapping,
468 struct writeback_control *wbc)
469{
470 struct blk_plug plug;
471 int err;
472
473 blk_start_plug(&plug);
474 err = write_cache_pages(mapping, wbc, metapage_write_folio, NULL);
475 blk_finish_plug(&plug);
476
477 return err;
478}
479
480static int metapage_read_folio(struct file *fp, struct folio *folio)
481{
482 struct inode *inode = folio->mapping->host;
483 struct bio *bio = NULL;
484 int block_offset;
485 int blocks_per_page = i_blocks_per_folio(inode, folio);
486 sector_t page_start; /* address of page in fs blocks */
487 sector_t pblock;
488 int xlen;
489 unsigned int len;
490 int offset;
491
492 BUG_ON(!folio_test_locked(folio));
493 page_start = folio_pos(folio) >> inode->i_blkbits;
494
495 block_offset = 0;
496 while (block_offset < blocks_per_page) {
497 xlen = blocks_per_page - block_offset;
498 pblock = metapage_get_blocks(inode, page_start + block_offset,
499 &xlen);
500 if (pblock) {
501 if (!folio->private)
502 insert_metapage(folio, NULL);
503 inc_io(folio);
504 if (bio)
505 submit_bio(bio);
506
507 bio = bio_alloc(inode->i_sb->s_bdev, 1, REQ_OP_READ,
508 GFP_NOFS);
509 bio->bi_iter.bi_sector =
510 pblock << (inode->i_blkbits - 9);
511 bio->bi_end_io = metapage_read_end_io;
512 bio->bi_private = folio;
513 len = xlen << inode->i_blkbits;
514 offset = block_offset << inode->i_blkbits;
515 bio_add_folio_nofail(bio, folio, len, offset);
516 block_offset += xlen;
517 } else
518 block_offset++;
519 }
520 if (bio)
521 submit_bio(bio);
522 else
523 folio_unlock(folio);
524
525 return 0;
526}
527
528static bool metapage_release_folio(struct folio *folio, gfp_t gfp_mask)
529{
530 struct metapage *mp;
531 bool ret = true;
532 int offset;
533
534 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
535 mp = folio_to_mp(folio, offset);
536
537 if (!mp)
538 continue;
539
540 jfs_info("metapage_release_folio: mp = 0x%p", mp);
541 if (mp->count || mp->nohomeok ||
542 test_bit(META_dirty, &mp->flag)) {
543 jfs_info("count = %ld, nohomeok = %d", mp->count,
544 mp->nohomeok);
545 ret = false;
546 continue;
547 }
548 if (mp->lsn)
549 remove_from_logsync(mp);
550 remove_metapage(folio, mp);
551 INCREMENT(mpStat.pagefree);
552 free_metapage(mp);
553 }
554 return ret;
555}
556
557static void metapage_invalidate_folio(struct folio *folio, size_t offset,
558 size_t length)
559{
560 BUG_ON(offset || length < folio_size(folio));
561
562 BUG_ON(folio_test_writeback(folio));
563
564 metapage_release_folio(folio, 0);
565}
566
567const struct address_space_operations jfs_metapage_aops = {
568 .read_folio = metapage_read_folio,
569 .writepages = metapage_writepages,
570 .release_folio = metapage_release_folio,
571 .invalidate_folio = metapage_invalidate_folio,
572 .dirty_folio = filemap_dirty_folio,
573};
574
575struct metapage *__get_metapage(struct inode *inode, unsigned long lblock,
576 unsigned int size, int absolute,
577 unsigned long new)
578{
579 int l2BlocksPerPage;
580 int l2bsize;
581 struct address_space *mapping;
582 struct metapage *mp = NULL;
583 struct folio *folio;
584 unsigned long page_index;
585 unsigned long page_offset;
586
587 jfs_info("__get_metapage: ino = %ld, lblock = 0x%lx, abs=%d",
588 inode->i_ino, lblock, absolute);
589
590 l2bsize = inode->i_blkbits;
591 l2BlocksPerPage = PAGE_SHIFT - l2bsize;
592 page_index = lblock >> l2BlocksPerPage;
593 page_offset = (lblock - (page_index << l2BlocksPerPage)) << l2bsize;
594 if ((page_offset + size) > PAGE_SIZE) {
595 jfs_err("MetaData crosses page boundary!!");
596 jfs_err("lblock = %lx, size = %d", lblock, size);
597 dump_stack();
598 return NULL;
599 }
600 if (absolute)
601 mapping = JFS_SBI(inode->i_sb)->direct_inode->i_mapping;
602 else {
603 /*
604 * If an nfs client tries to read an inode that is larger
605 * than any existing inodes, we may try to read past the
606 * end of the inode map
607 */
608 if ((lblock << inode->i_blkbits) >= inode->i_size)
609 return NULL;
610 mapping = inode->i_mapping;
611 }
612
613 if (new && (PSIZE == PAGE_SIZE)) {
614 folio = filemap_grab_folio(mapping, page_index);
615 if (IS_ERR(folio)) {
616 jfs_err("filemap_grab_folio failed!");
617 return NULL;
618 }
619 folio_mark_uptodate(folio);
620 } else {
621 folio = read_mapping_folio(mapping, page_index, NULL);
622 if (IS_ERR(folio)) {
623 jfs_err("read_mapping_page failed!");
624 return NULL;
625 }
626 folio_lock(folio);
627 }
628
629 mp = folio_to_mp(folio, page_offset);
630 if (mp) {
631 if (mp->logical_size != size) {
632 jfs_error(inode->i_sb,
633 "get_mp->logical_size != size\n");
634 jfs_err("logical_size = %d, size = %d",
635 mp->logical_size, size);
636 dump_stack();
637 goto unlock;
638 }
639 mp->count++;
640 lock_metapage(mp);
641 if (test_bit(META_discard, &mp->flag)) {
642 if (!new) {
643 jfs_error(inode->i_sb,
644 "using a discarded metapage\n");
645 discard_metapage(mp);
646 goto unlock;
647 }
648 clear_bit(META_discard, &mp->flag);
649 }
650 } else {
651 INCREMENT(mpStat.pagealloc);
652 mp = alloc_metapage(GFP_NOFS);
653 if (!mp)
654 goto unlock;
655 mp->folio = folio;
656 mp->sb = inode->i_sb;
657 mp->flag = 0;
658 mp->xflag = COMMIT_PAGE;
659 mp->count = 1;
660 mp->nohomeok = 0;
661 mp->logical_size = size;
662 mp->data = folio_address(folio) + page_offset;
663 mp->index = lblock;
664 if (unlikely(insert_metapage(folio, mp))) {
665 free_metapage(mp);
666 goto unlock;
667 }
668 lock_metapage(mp);
669 }
670
671 if (new) {
672 jfs_info("zeroing mp = 0x%p", mp);
673 memset(mp->data, 0, PSIZE);
674 }
675
676 folio_unlock(folio);
677 jfs_info("__get_metapage: returning = 0x%p data = 0x%p", mp, mp->data);
678 return mp;
679
680unlock:
681 folio_unlock(folio);
682 return NULL;
683}
684
685void grab_metapage(struct metapage * mp)
686{
687 jfs_info("grab_metapage: mp = 0x%p", mp);
688 folio_get(mp->folio);
689 folio_lock(mp->folio);
690 mp->count++;
691 lock_metapage(mp);
692 folio_unlock(mp->folio);
693}
694
695static int metapage_write_one(struct folio *folio)
696{
697 struct address_space *mapping = folio->mapping;
698 struct writeback_control wbc = {
699 .sync_mode = WB_SYNC_ALL,
700 .nr_to_write = folio_nr_pages(folio),
701 };
702 int ret = 0;
703
704 BUG_ON(!folio_test_locked(folio));
705
706 folio_wait_writeback(folio);
707
708 if (folio_clear_dirty_for_io(folio)) {
709 folio_get(folio);
710 ret = metapage_write_folio(folio, &wbc, NULL);
711 if (ret == 0)
712 folio_wait_writeback(folio);
713 folio_put(folio);
714 } else {
715 folio_unlock(folio);
716 }
717
718 if (!ret)
719 ret = filemap_check_errors(mapping);
720 return ret;
721}
722
723void force_metapage(struct metapage *mp)
724{
725 struct folio *folio = mp->folio;
726 jfs_info("force_metapage: mp = 0x%p", mp);
727 set_bit(META_forcewrite, &mp->flag);
728 clear_bit(META_sync, &mp->flag);
729 folio_get(folio);
730 folio_lock(folio);
731 folio_mark_dirty(folio);
732 if (metapage_write_one(folio))
733 jfs_error(mp->sb, "metapage_write_one() failed\n");
734 clear_bit(META_forcewrite, &mp->flag);
735 folio_put(folio);
736}
737
738void hold_metapage(struct metapage *mp)
739{
740 folio_lock(mp->folio);
741}
742
743void put_metapage(struct metapage *mp)
744{
745 if (mp->count || mp->nohomeok) {
746 /* Someone else will release this */
747 folio_unlock(mp->folio);
748 return;
749 }
750 folio_get(mp->folio);
751 mp->count++;
752 lock_metapage(mp);
753 folio_unlock(mp->folio);
754 release_metapage(mp);
755}
756
757void release_metapage(struct metapage * mp)
758{
759 struct folio *folio = mp->folio;
760 jfs_info("release_metapage: mp = 0x%p, flag = 0x%lx", mp, mp->flag);
761
762 folio_lock(folio);
763 unlock_metapage(mp);
764
765 assert(mp->count);
766 if (--mp->count || mp->nohomeok) {
767 folio_unlock(folio);
768 folio_put(folio);
769 return;
770 }
771
772 if (test_bit(META_dirty, &mp->flag)) {
773 folio_mark_dirty(folio);
774 if (test_bit(META_sync, &mp->flag)) {
775 clear_bit(META_sync, &mp->flag);
776 if (metapage_write_one(folio))
777 jfs_error(mp->sb, "metapage_write_one() failed\n");
778 folio_lock(folio);
779 }
780 } else if (mp->lsn) /* discard_metapage doesn't remove it */
781 remove_from_logsync(mp);
782
783 /* Try to keep metapages from using up too much memory */
784 drop_metapage(folio, mp);
785
786 folio_unlock(folio);
787 folio_put(folio);
788}
789
790void __invalidate_metapages(struct inode *ip, s64 addr, int len)
791{
792 sector_t lblock;
793 int l2BlocksPerPage = PAGE_SHIFT - ip->i_blkbits;
794 int BlocksPerPage = 1 << l2BlocksPerPage;
795 /* All callers are interested in block device's mapping */
796 struct address_space *mapping =
797 JFS_SBI(ip->i_sb)->direct_inode->i_mapping;
798 struct metapage *mp;
799 unsigned int offset;
800
801 /*
802 * Mark metapages to discard. They will eventually be
803 * released, but should not be written.
804 */
805 for (lblock = addr & ~(BlocksPerPage - 1); lblock < addr + len;
806 lblock += BlocksPerPage) {
807 struct folio *folio = filemap_lock_folio(mapping,
808 lblock >> l2BlocksPerPage);
809 if (IS_ERR(folio))
810 continue;
811 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
812 mp = folio_to_mp(folio, offset);
813 if (!mp)
814 continue;
815 if (mp->index < addr)
816 continue;
817 if (mp->index >= addr + len)
818 break;
819
820 clear_bit(META_dirty, &mp->flag);
821 set_bit(META_discard, &mp->flag);
822 if (mp->lsn)
823 remove_from_logsync(mp);
824 }
825 folio_unlock(folio);
826 folio_put(folio);
827 }
828}
829
830#ifdef CONFIG_JFS_STATISTICS
831int jfs_mpstat_proc_show(struct seq_file *m, void *v)
832{
833 seq_printf(m,
834 "JFS Metapage statistics\n"
835 "=======================\n"
836 "page allocations = %d\n"
837 "page frees = %d\n"
838 "lock waits = %d\n",
839 mpStat.pagealloc,
840 mpStat.pagefree,
841 mpStat.lockwait);
842 return 0;
843}
844#endif