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
26 static 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
36 static inline void unlock_metapage(struct metapage *mp)
37 {
38 clear_bit_unlock(META_locked, &mp->flag);
39 wake_up(&mp->wait);
40 }
41
42 static 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 */
62 static 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
69 static struct kmem_cache *metapage_cache;
70 static mempool_t *metapage_mempool;
71
72 #define MPS_PER_PAGE (PAGE_SIZE >> L2PSIZE)
73
74 #if MPS_PER_PAGE > 1
75
76 struct 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
83 static 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
92 static 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
117 static 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
135 static inline void inc_io(struct folio *folio)
136 {
137 struct meta_anchor *anchor = folio->private;
138
139 atomic_inc(&anchor->io_count);
140 }
141
142 static 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
155 static inline struct metapage *folio_to_mp(struct folio *folio, int offset)
156 {
157 return folio->private;
158 }
159
160 static 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
169 static 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
180 static 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
195 static inline void free_metapage(struct metapage *mp)
196 {
197 mempool_free(mp, metapage_mempool);
198 }
199
200 int __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
221 void metapage_exit(void)
222 {
223 mempool_destroy(metapage_mempool);
224 kmem_cache_destroy(metapage_cache);
225 }
226
227 static 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
241 static 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
266 static 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
275 static 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
283 static 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
305 static 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
331 static 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
341 static 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;
455 dump_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);
461 err_out:
462 while (bad_blocks--)
463 dec_io(folio, BLK_STS_OK, last_write_complete);
464 return -EIO;
465 }
466
467 static 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
480 static 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
528 static 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
557 static 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
567 const 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
575 struct 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
680 unlock:
681 folio_unlock(folio);
682 return NULL;
683 }
684
685 void 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
695 static 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
723 void 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
738 void hold_metapage(struct metapage *mp)
739 {
740 folio_lock(mp->folio);
741 }
742
743 void 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
757 void 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
790 void __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
831 int 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
845
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