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crypto: x86/blowfish - Fix RBP usage
[linux/fpc-iii.git] / fs / jfs / jfs_metapage.c
blob1c4b9ad4d7ab66446dae9241f44abe69429d33fb
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
37 static 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
47 static inline void unlock_metapage(struct metapage *mp)
48 {
49 clear_bit_unlock(META_locked, &mp->flag);
50 wake_up(&mp->wait);
51 }
52
53 static 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 */
73 static 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
80 static struct kmem_cache *metapage_cache;
81 static mempool_t *metapage_mempool;
82
83 #define MPS_PER_PAGE (PAGE_SIZE >> L2PSIZE)
84
85 #if MPS_PER_PAGE > 1
86
87 struct 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
94 static 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
101 static 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
128 static 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
147 static inline void inc_io(struct page *page)
148 {
149 atomic_inc(&mp_anchor(page)->io_count);
150 }
151
152 static 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
159 static inline struct metapage *page_to_mp(struct page *page, int offset)
160 {
161 return PagePrivate(page) ? (struct metapage *)page_private(page) : NULL;
162 }
163
164 static 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
174 static 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
186 static 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
201 static inline void free_metapage(struct metapage *mp)
202 {
203 mempool_free(mp, metapage_mempool);
204 }
205
206 int __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
227 void metapage_exit(void)
228 {
229 mempool_destroy(metapage_mempool);
230 kmem_cache_destroy(metapage_cache);
231 }
232
233 static 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
247 static 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
272 static void last_read_complete(struct page *page)
273 {
274 if (!PageError(page))
275 SetPageUptodate(page);
276 unlock_page(page);
277 }
278
279 static 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
292 static 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
314 static 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
334 static 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
348 static 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;
467 add_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;
471 dump_bio:
472 print_hex_dump(KERN_ERR, "JFS: dump of bio: ", DUMP_PREFIX_ADDRESS, 16,
473 4, bio, sizeof(*bio), 0);
474 skip:
475 bio_put(bio);
476 unlock_page(page);
477 dec_io(page, last_write_complete);
478 err_out:
479 while (bad_blocks--)
480 dec_io(page, last_write_complete);
481 return -EIO;
482 }
483
484 static 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
534 add_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
541 static 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
570 static 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
580 const 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
588 struct 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 mp->page = page;
667 mp->sb = inode->i_sb;
668 mp->flag = 0;
669 mp->xflag = COMMIT_PAGE;
670 mp->count = 1;
671 mp->nohomeok = 0;
672 mp->logical_size = size;
673 mp->data = page_address(page) + page_offset;
674 mp->index = lblock;
675 if (unlikely(insert_metapage(page, mp))) {
676 free_metapage(mp);
677 goto unlock;
678 }
679 lock_metapage(mp);
680 }
681
682 if (new) {
683 jfs_info("zeroing mp = 0x%p", mp);
684 memset(mp->data, 0, PSIZE);
685 }
686
687 unlock_page(page);
688 jfs_info("__get_metapage: returning = 0x%p data = 0x%p", mp, mp->data);
689 return mp;
690
691 unlock:
692 unlock_page(page);
693 return NULL;
694 }
695
696 void grab_metapage(struct metapage * mp)
697 {
698 jfs_info("grab_metapage: mp = 0x%p", mp);
699 get_page(mp->page);
700 lock_page(mp->page);
701 mp->count++;
702 lock_metapage(mp);
703 unlock_page(mp->page);
704 }
705
706 void force_metapage(struct metapage *mp)
707 {
708 struct page *page = mp->page;
709 jfs_info("force_metapage: mp = 0x%p", mp);
710 set_bit(META_forcewrite, &mp->flag);
711 clear_bit(META_sync, &mp->flag);
712 get_page(page);
713 lock_page(page);
714 set_page_dirty(page);
715 if (write_one_page(page))
716 jfs_error(mp->sb, "write_one_page() failed\n");
717 clear_bit(META_forcewrite, &mp->flag);
718 put_page(page);
719 }
720
721 void hold_metapage(struct metapage *mp)
722 {
723 lock_page(mp->page);
724 }
725
726 void put_metapage(struct metapage *mp)
727 {
728 if (mp->count || mp->nohomeok) {
729 /* Someone else will release this */
730 unlock_page(mp->page);
731 return;
732 }
733 get_page(mp->page);
734 mp->count++;
735 lock_metapage(mp);
736 unlock_page(mp->page);
737 release_metapage(mp);
738 }
739
740 void release_metapage(struct metapage * mp)
741 {
742 struct page *page = mp->page;
743 jfs_info("release_metapage: mp = 0x%p, flag = 0x%lx", mp, mp->flag);
744
745 BUG_ON(!page);
746
747 lock_page(page);
748 unlock_metapage(mp);
749
750 assert(mp->count);
751 if (--mp->count || mp->nohomeok) {
752 unlock_page(page);
753 put_page(page);
754 return;
755 }
756
757 if (test_bit(META_dirty, &mp->flag)) {
758 set_page_dirty(page);
759 if (test_bit(META_sync, &mp->flag)) {
760 clear_bit(META_sync, &mp->flag);
761 if (write_one_page(page))
762 jfs_error(mp->sb, "write_one_page() failed\n");
763 lock_page(page); /* write_one_page unlocks the page */
764 }
765 } else if (mp->lsn) /* discard_metapage doesn't remove it */
766 remove_from_logsync(mp);
767
768 /* Try to keep metapages from using up too much memory */
769 drop_metapage(page, mp);
770
771 unlock_page(page);
772 put_page(page);
773 }
774
775 void __invalidate_metapages(struct inode *ip, s64 addr, int len)
776 {
777 sector_t lblock;
778 int l2BlocksPerPage = PAGE_SHIFT - ip->i_blkbits;
779 int BlocksPerPage = 1 << l2BlocksPerPage;
780 /* All callers are interested in block device's mapping */
781 struct address_space *mapping =
782 JFS_SBI(ip->i_sb)->direct_inode->i_mapping;
783 struct metapage *mp;
784 struct page *page;
785 unsigned int offset;
786
787 /*
788 * Mark metapages to discard. They will eventually be
789 * released, but should not be written.
790 */
791 for (lblock = addr & ~(BlocksPerPage - 1); lblock < addr + len;
792 lblock += BlocksPerPage) {
793 page = find_lock_page(mapping, lblock >> l2BlocksPerPage);
794 if (!page)
795 continue;
796 for (offset = 0; offset < PAGE_SIZE; offset += PSIZE) {
797 mp = page_to_mp(page, offset);
798 if (!mp)
799 continue;
800 if (mp->index < addr)
801 continue;
802 if (mp->index >= addr + len)
803 break;
804
805 clear_bit(META_dirty, &mp->flag);
806 set_bit(META_discard, &mp->flag);
807 if (mp->lsn)
808 remove_from_logsync(mp);
809 }
810 unlock_page(page);
811 put_page(page);
812 }
813 }
814
815 #ifdef CONFIG_JFS_STATISTICS
816 static int jfs_mpstat_proc_show(struct seq_file *m, void *v)
817 {
818 seq_printf(m,
819 "JFS Metapage statistics\n"
820 "=======================\n"
821 "page allocations = %d\n"
822 "page frees = %d\n"
823 "lock waits = %d\n",
824 mpStat.pagealloc,
825 mpStat.pagefree,
826 mpStat.lockwait);
827 return 0;
828 }
829
830 static int jfs_mpstat_proc_open(struct inode *inode, struct file *file)
831 {
832 return single_open(file, jfs_mpstat_proc_show, NULL);
833 }
834
835 const struct file_operations jfs_mpstat_proc_fops = {
836 .open = jfs_mpstat_proc_open,
837 .read = seq_read,
838 .llseek = seq_lseek,
839 .release = single_release,
840 };
841 #endif
Linux with added FPC-III support