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18#include "xfs.h"
19#include "xfs_bit.h"
20#include "xfs_log.h"
21#include "xfs_inum.h"
22#include "xfs_sb.h"
23#include "xfs_ag.h"
24#include "xfs_trans.h"
25#include "xfs_mount.h"
26#include "xfs_bmap_btree.h"
27#include "xfs_dinode.h"
28#include "xfs_inode.h"
29#include "xfs_alloc.h"
30#include "xfs_error.h"
31#include "xfs_rw.h"
32#include "xfs_iomap.h"
33#include "xfs_vnodeops.h"
34#include "xfs_trace.h"
35#include "xfs_bmap.h"
36#include <linux/gfp.h>
37#include <linux/mpage.h>
38#include <linux/pagevec.h>
39#include <linux/writeback.h>
40
41
42
43
44
45#define NVSYNC 37
46#define to_ioend_wq(v) (&xfs_ioend_wq[((unsigned long)v) % NVSYNC])
47static wait_queue_head_t xfs_ioend_wq[NVSYNC];
48
49void __init
50xfs_ioend_init(void)
51{
52 int i;
53
54 for (i = 0; i < NVSYNC; i++)
55 init_waitqueue_head(&xfs_ioend_wq[i]);
56}
57
58void
59xfs_ioend_wait(
60 xfs_inode_t *ip)
61{
62 wait_queue_head_t *wq = to_ioend_wq(ip);
63
64 wait_event(*wq, (atomic_read(&ip->i_iocount) == 0));
65}
66
67STATIC void
68xfs_ioend_wake(
69 xfs_inode_t *ip)
70{
71 if (atomic_dec_and_test(&ip->i_iocount))
72 wake_up(to_ioend_wq(ip));
73}
74
75void
76xfs_count_page_state(
77 struct page *page,
78 int *delalloc,
79 int *unwritten)
80{
81 struct buffer_head *bh, *head;
82
83 *delalloc = *unwritten = 0;
84
85 bh = head = page_buffers(page);
86 do {
87 if (buffer_unwritten(bh))
88 (*unwritten) = 1;
89 else if (buffer_delay(bh))
90 (*delalloc) = 1;
91 } while ((bh = bh->b_this_page) != head);
92}
93
94STATIC struct block_device *
95xfs_find_bdev_for_inode(
96 struct inode *inode)
97{
98 struct xfs_inode *ip = XFS_I(inode);
99 struct xfs_mount *mp = ip->i_mount;
100
101 if (XFS_IS_REALTIME_INODE(ip))
102 return mp->m_rtdev_targp->bt_bdev;
103 else
104 return mp->m_ddev_targp->bt_bdev;
105}
106
107
108
109
110
111
112
113STATIC void
114xfs_destroy_ioend(
115 xfs_ioend_t *ioend)
116{
117 struct buffer_head *bh, *next;
118 struct xfs_inode *ip = XFS_I(ioend->io_inode);
119
120 for (bh = ioend->io_buffer_head; bh; bh = next) {
121 next = bh->b_private;
122 bh->b_end_io(bh, !ioend->io_error);
123 }
124
125
126
127
128
129
130
131 if (unlikely(ioend->io_error == -ENODEV)) {
132 xfs_do_force_shutdown(ip->i_mount, SHUTDOWN_DEVICE_REQ,
133 __FILE__, __LINE__);
134 }
135
136 xfs_ioend_wake(ip);
137 mempool_free(ioend, xfs_ioend_pool);
138}
139
140
141
142
143
144STATIC xfs_fsize_t
145xfs_ioend_new_eof(
146 xfs_ioend_t *ioend)
147{
148 xfs_inode_t *ip = XFS_I(ioend->io_inode);
149 xfs_fsize_t isize;
150 xfs_fsize_t bsize;
151
152 bsize = ioend->io_offset + ioend->io_size;
153 isize = MAX(ip->i_size, ip->i_new_size);
154 isize = MIN(isize, bsize);
155 return isize > ip->i_d.di_size ? isize : 0;
156}
157
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161
162
163
164
165
166
167
168
169STATIC int
170xfs_setfilesize(
171 xfs_ioend_t *ioend)
172{
173 xfs_inode_t *ip = XFS_I(ioend->io_inode);
174 xfs_fsize_t isize;
175
176 if (unlikely(ioend->io_error))
177 return 0;
178
179 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL))
180 return EAGAIN;
181
182 isize = xfs_ioend_new_eof(ioend);
183 if (isize) {
184 ip->i_d.di_size = isize;
185 xfs_mark_inode_dirty(ip);
186 }
187
188 xfs_iunlock(ip, XFS_ILOCK_EXCL);
189 return 0;
190}
191
192
193
194
195STATIC void
196xfs_finish_ioend(
197 struct xfs_ioend *ioend)
198{
199 if (atomic_dec_and_test(&ioend->io_remaining)) {
200 if (ioend->io_type == IO_UNWRITTEN)
201 queue_work(xfsconvertd_workqueue, &ioend->io_work);
202 else
203 queue_work(xfsdatad_workqueue, &ioend->io_work);
204 }
205}
206
207
208
209
210STATIC void
211xfs_end_io(
212 struct work_struct *work)
213{
214 xfs_ioend_t *ioend = container_of(work, xfs_ioend_t, io_work);
215 struct xfs_inode *ip = XFS_I(ioend->io_inode);
216 int error = 0;
217
218
219
220
221
222 if (ioend->io_type == IO_UNWRITTEN &&
223 likely(!ioend->io_error && !XFS_FORCED_SHUTDOWN(ip->i_mount))) {
224
225 error = xfs_iomap_write_unwritten(ip, ioend->io_offset,
226 ioend->io_size);
227 if (error)
228 ioend->io_error = error;
229 }
230
231
232
233
234
235 error = xfs_setfilesize(ioend);
236 ASSERT(!error || error == EAGAIN);
237
238
239
240
241
242
243 if (error == EAGAIN) {
244 atomic_inc(&ioend->io_remaining);
245 xfs_finish_ioend(ioend);
246
247 delay(1);
248 } else {
249 if (ioend->io_iocb)
250 aio_complete(ioend->io_iocb, ioend->io_result, 0);
251 xfs_destroy_ioend(ioend);
252 }
253}
254
255
256
257
258STATIC void
259xfs_finish_ioend_sync(
260 struct xfs_ioend *ioend)
261{
262 if (atomic_dec_and_test(&ioend->io_remaining))
263 xfs_end_io(&ioend->io_work);
264}
265
266
267
268
269
270
271
272STATIC xfs_ioend_t *
273xfs_alloc_ioend(
274 struct inode *inode,
275 unsigned int type)
276{
277 xfs_ioend_t *ioend;
278
279 ioend = mempool_alloc(xfs_ioend_pool, GFP_NOFS);
280
281
282
283
284
285
286 atomic_set(&ioend->io_remaining, 1);
287 ioend->io_error = 0;
288 ioend->io_list = NULL;
289 ioend->io_type = type;
290 ioend->io_inode = inode;
291 ioend->io_buffer_head = NULL;
292 ioend->io_buffer_tail = NULL;
293 atomic_inc(&XFS_I(ioend->io_inode)->i_iocount);
294 ioend->io_offset = 0;
295 ioend->io_size = 0;
296 ioend->io_iocb = NULL;
297 ioend->io_result = 0;
298
299 INIT_WORK(&ioend->io_work, xfs_end_io);
300 return ioend;
301}
302
303STATIC int
304xfs_map_blocks(
305 struct inode *inode,
306 loff_t offset,
307 struct xfs_bmbt_irec *imap,
308 int type,
309 int nonblocking)
310{
311 struct xfs_inode *ip = XFS_I(inode);
312 struct xfs_mount *mp = ip->i_mount;
313 ssize_t count = 1 << inode->i_blkbits;
314 xfs_fileoff_t offset_fsb, end_fsb;
315 int error = 0;
316 int bmapi_flags = XFS_BMAPI_ENTIRE;
317 int nimaps = 1;
318
319 if (XFS_FORCED_SHUTDOWN(mp))
320 return -XFS_ERROR(EIO);
321
322 if (type == IO_UNWRITTEN)
323 bmapi_flags |= XFS_BMAPI_IGSTATE;
324
325 if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
326 if (nonblocking)
327 return -XFS_ERROR(EAGAIN);
328 xfs_ilock(ip, XFS_ILOCK_SHARED);
329 }
330
331 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
332 (ip->i_df.if_flags & XFS_IFEXTENTS));
333 ASSERT(offset <= mp->m_maxioffset);
334
335 if (offset + count > mp->m_maxioffset)
336 count = mp->m_maxioffset - offset;
337 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
338 offset_fsb = XFS_B_TO_FSBT(mp, offset);
339 error = xfs_bmapi(NULL, ip, offset_fsb, end_fsb - offset_fsb,
340 bmapi_flags, NULL, 0, imap, &nimaps, NULL);
341 xfs_iunlock(ip, XFS_ILOCK_SHARED);
342
343 if (error)
344 return -XFS_ERROR(error);
345
346 if (type == IO_DELALLOC &&
347 (!nimaps || isnullstartblock(imap->br_startblock))) {
348 error = xfs_iomap_write_allocate(ip, offset, count, imap);
349 if (!error)
350 trace_xfs_map_blocks_alloc(ip, offset, count, type, imap);
351 return -XFS_ERROR(error);
352 }
353
354#ifdef DEBUG
355 if (type == IO_UNWRITTEN) {
356 ASSERT(nimaps);
357 ASSERT(imap->br_startblock != HOLESTARTBLOCK);
358 ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
359 }
360#endif
361 if (nimaps)
362 trace_xfs_map_blocks_found(ip, offset, count, type, imap);
363 return 0;
364}
365
366STATIC int
367xfs_imap_valid(
368 struct inode *inode,
369 struct xfs_bmbt_irec *imap,
370 xfs_off_t offset)
371{
372 offset >>= inode->i_blkbits;
373
374 return offset >= imap->br_startoff &&
375 offset < imap->br_startoff + imap->br_blockcount;
376}
377
378
379
380
381STATIC void
382xfs_end_bio(
383 struct bio *bio,
384 int error)
385{
386 xfs_ioend_t *ioend = bio->bi_private;
387
388 ASSERT(atomic_read(&bio->bi_cnt) >= 1);
389 ioend->io_error = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : error;
390
391
392 bio->bi_private = NULL;
393 bio->bi_end_io = NULL;
394 bio_put(bio);
395
396 xfs_finish_ioend(ioend);
397}
398
399STATIC void
400xfs_submit_ioend_bio(
401 struct writeback_control *wbc,
402 xfs_ioend_t *ioend,
403 struct bio *bio)
404{
405 atomic_inc(&ioend->io_remaining);
406 bio->bi_private = ioend;
407 bio->bi_end_io = xfs_end_bio;
408
409
410
411
412
413 if (xfs_ioend_new_eof(ioend))
414 xfs_mark_inode_dirty(XFS_I(ioend->io_inode));
415
416 submit_bio(wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE, bio);
417}
418
419STATIC struct bio *
420xfs_alloc_ioend_bio(
421 struct buffer_head *bh)
422{
423 int nvecs = bio_get_nr_vecs(bh->b_bdev);
424 struct bio *bio = bio_alloc(GFP_NOIO, nvecs);
425
426 ASSERT(bio->bi_private == NULL);
427 bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
428 bio->bi_bdev = bh->b_bdev;
429 return bio;
430}
431
432STATIC void
433xfs_start_buffer_writeback(
434 struct buffer_head *bh)
435{
436 ASSERT(buffer_mapped(bh));
437 ASSERT(buffer_locked(bh));
438 ASSERT(!buffer_delay(bh));
439 ASSERT(!buffer_unwritten(bh));
440
441 mark_buffer_async_write(bh);
442 set_buffer_uptodate(bh);
443 clear_buffer_dirty(bh);
444}
445
446STATIC void
447xfs_start_page_writeback(
448 struct page *page,
449 int clear_dirty,
450 int buffers)
451{
452 ASSERT(PageLocked(page));
453 ASSERT(!PageWriteback(page));
454 if (clear_dirty)
455 clear_page_dirty_for_io(page);
456 set_page_writeback(page);
457 unlock_page(page);
458
459 if (!buffers)
460 end_page_writeback(page);
461}
462
463static inline int bio_add_buffer(struct bio *bio, struct buffer_head *bh)
464{
465 return bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
466}
467
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482
483
484
485STATIC void
486xfs_submit_ioend(
487 struct writeback_control *wbc,
488 xfs_ioend_t *ioend)
489{
490 xfs_ioend_t *head = ioend;
491 xfs_ioend_t *next;
492 struct buffer_head *bh;
493 struct bio *bio;
494 sector_t lastblock = 0;
495
496
497 do {
498 next = ioend->io_list;
499 for (bh = ioend->io_buffer_head; bh; bh = bh->b_private)
500 xfs_start_buffer_writeback(bh);
501 } while ((ioend = next) != NULL);
502
503
504 ioend = head;
505 do {
506 next = ioend->io_list;
507 bio = NULL;
508
509 for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
510
511 if (!bio) {
512 retry:
513 bio = xfs_alloc_ioend_bio(bh);
514 } else if (bh->b_blocknr != lastblock + 1) {
515 xfs_submit_ioend_bio(wbc, ioend, bio);
516 goto retry;
517 }
518
519 if (bio_add_buffer(bio, bh) != bh->b_size) {
520 xfs_submit_ioend_bio(wbc, ioend, bio);
521 goto retry;
522 }
523
524 lastblock = bh->b_blocknr;
525 }
526 if (bio)
527 xfs_submit_ioend_bio(wbc, ioend, bio);
528 xfs_finish_ioend(ioend);
529 } while ((ioend = next) != NULL);
530}
531
532
533
534
535
536
537STATIC void
538xfs_cancel_ioend(
539 xfs_ioend_t *ioend)
540{
541 xfs_ioend_t *next;
542 struct buffer_head *bh, *next_bh;
543
544 do {
545 next = ioend->io_list;
546 bh = ioend->io_buffer_head;
547 do {
548 next_bh = bh->b_private;
549 clear_buffer_async_write(bh);
550 unlock_buffer(bh);
551 } while ((bh = next_bh) != NULL);
552
553 xfs_ioend_wake(XFS_I(ioend->io_inode));
554 mempool_free(ioend, xfs_ioend_pool);
555 } while ((ioend = next) != NULL);
556}
557
558
559
560
561
562
563
564STATIC void
565xfs_add_to_ioend(
566 struct inode *inode,
567 struct buffer_head *bh,
568 xfs_off_t offset,
569 unsigned int type,
570 xfs_ioend_t **result,
571 int need_ioend)
572{
573 xfs_ioend_t *ioend = *result;
574
575 if (!ioend || need_ioend || type != ioend->io_type) {
576 xfs_ioend_t *previous = *result;
577
578 ioend = xfs_alloc_ioend(inode, type);
579 ioend->io_offset = offset;
580 ioend->io_buffer_head = bh;
581 ioend->io_buffer_tail = bh;
582 if (previous)
583 previous->io_list = ioend;
584 *result = ioend;
585 } else {
586 ioend->io_buffer_tail->b_private = bh;
587 ioend->io_buffer_tail = bh;
588 }
589
590 bh->b_private = NULL;
591 ioend->io_size += bh->b_size;
592}
593
594STATIC void
595xfs_map_buffer(
596 struct inode *inode,
597 struct buffer_head *bh,
598 struct xfs_bmbt_irec *imap,
599 xfs_off_t offset)
600{
601 sector_t bn;
602 struct xfs_mount *m = XFS_I(inode)->i_mount;
603 xfs_off_t iomap_offset = XFS_FSB_TO_B(m, imap->br_startoff);
604 xfs_daddr_t iomap_bn = xfs_fsb_to_db(XFS_I(inode), imap->br_startblock);
605
606 ASSERT(imap->br_startblock != HOLESTARTBLOCK);
607 ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
608
609 bn = (iomap_bn >> (inode->i_blkbits - BBSHIFT)) +
610 ((offset - iomap_offset) >> inode->i_blkbits);
611
612 ASSERT(bn || XFS_IS_REALTIME_INODE(XFS_I(inode)));
613
614 bh->b_blocknr = bn;
615 set_buffer_mapped(bh);
616}
617
618STATIC void
619xfs_map_at_offset(
620 struct inode *inode,
621 struct buffer_head *bh,
622 struct xfs_bmbt_irec *imap,
623 xfs_off_t offset)
624{
625 ASSERT(imap->br_startblock != HOLESTARTBLOCK);
626 ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
627
628 xfs_map_buffer(inode, bh, imap, offset);
629 set_buffer_mapped(bh);
630 clear_buffer_delay(bh);
631 clear_buffer_unwritten(bh);
632}
633
634
635
636
637
638STATIC int
639xfs_is_delayed_page(
640 struct page *page,
641 unsigned int type)
642{
643 if (PageWriteback(page))
644 return 0;
645
646 if (page->mapping && page_has_buffers(page)) {
647 struct buffer_head *bh, *head;
648 int acceptable = 0;
649
650 bh = head = page_buffers(page);
651 do {
652 if (buffer_unwritten(bh))
653 acceptable = (type == IO_UNWRITTEN);
654 else if (buffer_delay(bh))
655 acceptable = (type == IO_DELALLOC);
656 else if (buffer_dirty(bh) && buffer_mapped(bh))
657 acceptable = (type == IO_OVERWRITE);
658 else
659 break;
660 } while ((bh = bh->b_this_page) != head);
661
662 if (acceptable)
663 return 1;
664 }
665
666 return 0;
667}
668
669
670
671
672
673
674
675STATIC int
676xfs_convert_page(
677 struct inode *inode,
678 struct page *page,
679 loff_t tindex,
680 struct xfs_bmbt_irec *imap,
681 xfs_ioend_t **ioendp,
682 struct writeback_control *wbc)
683{
684 struct buffer_head *bh, *head;
685 xfs_off_t end_offset;
686 unsigned long p_offset;
687 unsigned int type;
688 int len, page_dirty;
689 int count = 0, done = 0, uptodate = 1;
690 xfs_off_t offset = page_offset(page);
691
692 if (page->index != tindex)
693 goto fail;
694 if (!trylock_page(page))
695 goto fail;
696 if (PageWriteback(page))
697 goto fail_unlock_page;
698 if (page->mapping != inode->i_mapping)
699 goto fail_unlock_page;
700 if (!xfs_is_delayed_page(page, (*ioendp)->io_type))
701 goto fail_unlock_page;
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716 end_offset = min_t(unsigned long long,
717 (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
718 i_size_read(inode));
719
720 len = 1 << inode->i_blkbits;
721 p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
722 PAGE_CACHE_SIZE);
723 p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
724 page_dirty = p_offset / len;
725
726 bh = head = page_buffers(page);
727 do {
728 if (offset >= end_offset)
729 break;
730 if (!buffer_uptodate(bh))
731 uptodate = 0;
732 if (!(PageUptodate(page) || buffer_uptodate(bh))) {
733 done = 1;
734 continue;
735 }
736
737 if (buffer_unwritten(bh) || buffer_delay(bh) ||
738 buffer_mapped(bh)) {
739 if (buffer_unwritten(bh))
740 type = IO_UNWRITTEN;
741 else if (buffer_delay(bh))
742 type = IO_DELALLOC;
743 else
744 type = IO_OVERWRITE;
745
746 if (!xfs_imap_valid(inode, imap, offset)) {
747 done = 1;
748 continue;
749 }
750
751 lock_buffer(bh);
752 if (type != IO_OVERWRITE)
753 xfs_map_at_offset(inode, bh, imap, offset);
754 xfs_add_to_ioend(inode, bh, offset, type,
755 ioendp, done);
756
757 page_dirty--;
758 count++;
759 } else {
760 done = 1;
761 }
762 } while (offset += len, (bh = bh->b_this_page) != head);
763
764 if (uptodate && bh == head)
765 SetPageUptodate(page);
766
767 if (count) {
768 if (--wbc->nr_to_write <= 0 &&
769 wbc->sync_mode == WB_SYNC_NONE)
770 done = 1;
771 }
772 xfs_start_page_writeback(page, !page_dirty, count);
773
774 return done;
775 fail_unlock_page:
776 unlock_page(page);
777 fail:
778 return 1;
779}
780
781
782
783
784
785STATIC void
786xfs_cluster_write(
787 struct inode *inode,
788 pgoff_t tindex,
789 struct xfs_bmbt_irec *imap,
790 xfs_ioend_t **ioendp,
791 struct writeback_control *wbc,
792 pgoff_t tlast)
793{
794 struct pagevec pvec;
795 int done = 0, i;
796
797 pagevec_init(&pvec, 0);
798 while (!done && tindex <= tlast) {
799 unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
800
801 if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
802 break;
803
804 for (i = 0; i < pagevec_count(&pvec); i++) {
805 done = xfs_convert_page(inode, pvec.pages[i], tindex++,
806 imap, ioendp, wbc);
807 if (done)
808 break;
809 }
810
811 pagevec_release(&pvec);
812 cond_resched();
813 }
814}
815
816STATIC void
817xfs_vm_invalidatepage(
818 struct page *page,
819 unsigned long offset)
820{
821 trace_xfs_invalidatepage(page->mapping->host, page, offset);
822 block_invalidatepage(page, offset);
823}
824
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839
840
841STATIC void
842xfs_aops_discard_page(
843 struct page *page)
844{
845 struct inode *inode = page->mapping->host;
846 struct xfs_inode *ip = XFS_I(inode);
847 struct buffer_head *bh, *head;
848 loff_t offset = page_offset(page);
849
850 if (!xfs_is_delayed_page(page, IO_DELALLOC))
851 goto out_invalidate;
852
853 if (XFS_FORCED_SHUTDOWN(ip->i_mount))
854 goto out_invalidate;
855
856 xfs_alert(ip->i_mount,
857 "page discard on page %p, inode 0x%llx, offset %llu.",
858 page, ip->i_ino, offset);
859
860 xfs_ilock(ip, XFS_ILOCK_EXCL);
861 bh = head = page_buffers(page);
862 do {
863 int error;
864 xfs_fileoff_t start_fsb;
865
866 if (!buffer_delay(bh))
867 goto next_buffer;
868
869 start_fsb = XFS_B_TO_FSBT(ip->i_mount, offset);
870 error = xfs_bmap_punch_delalloc_range(ip, start_fsb, 1);
871 if (error) {
872
873 if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
874 xfs_alert(ip->i_mount,
875 "page discard unable to remove delalloc mapping.");
876 }
877 break;
878 }
879next_buffer:
880 offset += 1 << inode->i_blkbits;
881
882 } while ((bh = bh->b_this_page) != head);
883
884 xfs_iunlock(ip, XFS_ILOCK_EXCL);
885out_invalidate:
886 xfs_vm_invalidatepage(page, 0);
887 return;
888}
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903STATIC int
904xfs_vm_writepage(
905 struct page *page,
906 struct writeback_control *wbc)
907{
908 struct inode *inode = page->mapping->host;
909 int delalloc, unwritten;
910 struct buffer_head *bh, *head;
911 struct xfs_bmbt_irec imap;
912 xfs_ioend_t *ioend = NULL, *iohead = NULL;
913 loff_t offset;
914 unsigned int type;
915 __uint64_t end_offset;
916 pgoff_t end_index, last_index;
917 ssize_t len;
918 int err, imap_valid = 0, uptodate = 1;
919 int count = 0;
920 int nonblocking = 0;
921
922 trace_xfs_writepage(inode, page, 0);
923
924 ASSERT(page_has_buffers(page));
925
926
927
928
929
930
931
932
933
934
935
936
937 if ((current->flags & (PF_MEMALLOC|PF_KSWAPD)) == PF_MEMALLOC)
938 goto redirty;
939
940
941
942
943
944
945
946
947
948 xfs_count_page_state(page, &delalloc, &unwritten);
949 if ((current->flags & PF_FSTRANS) && (delalloc || unwritten))
950 goto redirty;
951
952
953 offset = i_size_read(inode);
954 end_index = offset >> PAGE_CACHE_SHIFT;
955 last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
956 if (page->index >= end_index) {
957 if ((page->index >= end_index + 1) ||
958 !(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
959 unlock_page(page);
960 return 0;
961 }
962 }
963
964 end_offset = min_t(unsigned long long,
965 (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
966 offset);
967 len = 1 << inode->i_blkbits;
968
969 bh = head = page_buffers(page);
970 offset = page_offset(page);
971 type = IO_OVERWRITE;
972
973 if (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking)
974 nonblocking = 1;
975
976 do {
977 int new_ioend = 0;
978
979 if (offset >= end_offset)
980 break;
981 if (!buffer_uptodate(bh))
982 uptodate = 0;
983
984
985
986
987
988
989
990 if (!buffer_mapped(bh) && buffer_uptodate(bh)) {
991 imap_valid = 0;
992 continue;
993 }
994
995 if (buffer_unwritten(bh)) {
996 if (type != IO_UNWRITTEN) {
997 type = IO_UNWRITTEN;
998 imap_valid = 0;
999 }
1000 } else if (buffer_delay(bh)) {
1001 if (type != IO_DELALLOC) {
1002 type = IO_DELALLOC;
1003 imap_valid = 0;
1004 }
1005 } else if (buffer_uptodate(bh)) {
1006 if (type != IO_OVERWRITE) {
1007 type = IO_OVERWRITE;
1008 imap_valid = 0;
1009 }
1010 } else {
1011 if (PageUptodate(page)) {
1012 ASSERT(buffer_mapped(bh));
1013 imap_valid = 0;
1014 }
1015 continue;
1016 }
1017
1018 if (imap_valid)
1019 imap_valid = xfs_imap_valid(inode, &imap, offset);
1020 if (!imap_valid) {
1021
1022
1023
1024
1025
1026
1027
1028
1029 new_ioend = 1;
1030 err = xfs_map_blocks(inode, offset, &imap, type,
1031 nonblocking);
1032 if (err)
1033 goto error;
1034 imap_valid = xfs_imap_valid(inode, &imap, offset);
1035 }
1036 if (imap_valid) {
1037 lock_buffer(bh);
1038 if (type != IO_OVERWRITE)
1039 xfs_map_at_offset(inode, bh, &imap, offset);
1040 xfs_add_to_ioend(inode, bh, offset, type, &ioend,
1041 new_ioend);
1042 count++;
1043 }
1044
1045 if (!iohead)
1046 iohead = ioend;
1047
1048 } while (offset += len, ((bh = bh->b_this_page) != head));
1049
1050 if (uptodate && bh == head)
1051 SetPageUptodate(page);
1052
1053 xfs_start_page_writeback(page, 1, count);
1054
1055 if (ioend && imap_valid) {
1056 xfs_off_t end_index;
1057
1058 end_index = imap.br_startoff + imap.br_blockcount;
1059
1060
1061 end_index <<= inode->i_blkbits;
1062
1063
1064 end_index = (end_index - 1) >> PAGE_CACHE_SHIFT;
1065
1066
1067 if (end_index > last_index)
1068 end_index = last_index;
1069
1070 xfs_cluster_write(inode, page->index + 1, &imap, &ioend,
1071 wbc, end_index);
1072 }
1073
1074 if (iohead)
1075 xfs_submit_ioend(wbc, iohead);
1076
1077 return 0;
1078
1079error:
1080 if (iohead)
1081 xfs_cancel_ioend(iohead);
1082
1083 if (err == -EAGAIN)
1084 goto redirty;
1085
1086 xfs_aops_discard_page(page);
1087 ClearPageUptodate(page);
1088 unlock_page(page);
1089 return err;
1090
1091redirty:
1092 redirty_page_for_writepage(wbc, page);
1093 unlock_page(page);
1094 return 0;
1095}
1096
1097STATIC int
1098xfs_vm_writepages(
1099 struct address_space *mapping,
1100 struct writeback_control *wbc)
1101{
1102 xfs_iflags_clear(XFS_I(mapping->host), XFS_ITRUNCATED);
1103 return generic_writepages(mapping, wbc);
1104}
1105
1106
1107
1108
1109
1110
1111
1112
1113STATIC int
1114xfs_vm_releasepage(
1115 struct page *page,
1116 gfp_t gfp_mask)
1117{
1118 int delalloc, unwritten;
1119
1120 trace_xfs_releasepage(page->mapping->host, page, 0);
1121
1122 xfs_count_page_state(page, &delalloc, &unwritten);
1123
1124 if (WARN_ON(delalloc))
1125 return 0;
1126 if (WARN_ON(unwritten))
1127 return 0;
1128
1129 return try_to_free_buffers(page);
1130}
1131
1132STATIC int
1133__xfs_get_blocks(
1134 struct inode *inode,
1135 sector_t iblock,
1136 struct buffer_head *bh_result,
1137 int create,
1138 int direct)
1139{
1140 struct xfs_inode *ip = XFS_I(inode);
1141 struct xfs_mount *mp = ip->i_mount;
1142 xfs_fileoff_t offset_fsb, end_fsb;
1143 int error = 0;
1144 int lockmode = 0;
1145 struct xfs_bmbt_irec imap;
1146 int nimaps = 1;
1147 xfs_off_t offset;
1148 ssize_t size;
1149 int new = 0;
1150
1151 if (XFS_FORCED_SHUTDOWN(mp))
1152 return -XFS_ERROR(EIO);
1153
1154 offset = (xfs_off_t)iblock << inode->i_blkbits;
1155 ASSERT(bh_result->b_size >= (1 << inode->i_blkbits));
1156 size = bh_result->b_size;
1157
1158 if (!create && direct && offset >= i_size_read(inode))
1159 return 0;
1160
1161 if (create) {
1162 lockmode = XFS_ILOCK_EXCL;
1163 xfs_ilock(ip, lockmode);
1164 } else {
1165 lockmode = xfs_ilock_map_shared(ip);
1166 }
1167
1168 ASSERT(offset <= mp->m_maxioffset);
1169 if (offset + size > mp->m_maxioffset)
1170 size = mp->m_maxioffset - offset;
1171 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + size);
1172 offset_fsb = XFS_B_TO_FSBT(mp, offset);
1173
1174 error = xfs_bmapi(NULL, ip, offset_fsb, end_fsb - offset_fsb,
1175 XFS_BMAPI_ENTIRE, NULL, 0, &imap, &nimaps, NULL);
1176 if (error)
1177 goto out_unlock;
1178
1179 if (create &&
1180 (!nimaps ||
1181 (imap.br_startblock == HOLESTARTBLOCK ||
1182 imap.br_startblock == DELAYSTARTBLOCK))) {
1183 if (direct) {
1184 error = xfs_iomap_write_direct(ip, offset, size,
1185 &imap, nimaps);
1186 } else {
1187 error = xfs_iomap_write_delay(ip, offset, size, &imap);
1188 }
1189 if (error)
1190 goto out_unlock;
1191
1192 trace_xfs_get_blocks_alloc(ip, offset, size, 0, &imap);
1193 } else if (nimaps) {
1194 trace_xfs_get_blocks_found(ip, offset, size, 0, &imap);
1195 } else {
1196 trace_xfs_get_blocks_notfound(ip, offset, size);
1197 goto out_unlock;
1198 }
1199 xfs_iunlock(ip, lockmode);
1200
1201 if (imap.br_startblock != HOLESTARTBLOCK &&
1202 imap.br_startblock != DELAYSTARTBLOCK) {
1203
1204
1205
1206
1207 if (create || !ISUNWRITTEN(&imap))
1208 xfs_map_buffer(inode, bh_result, &imap, offset);
1209 if (create && ISUNWRITTEN(&imap)) {
1210 if (direct)
1211 bh_result->b_private = inode;
1212 set_buffer_unwritten(bh_result);
1213 }
1214 }
1215
1216
1217
1218
1219
1220 bh_result->b_bdev = xfs_find_bdev_for_inode(inode);
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231 if (create &&
1232 ((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) ||
1233 (offset >= i_size_read(inode)) ||
1234 (new || ISUNWRITTEN(&imap))))
1235 set_buffer_new(bh_result);
1236
1237 if (imap.br_startblock == DELAYSTARTBLOCK) {
1238 BUG_ON(direct);
1239 if (create) {
1240 set_buffer_uptodate(bh_result);
1241 set_buffer_mapped(bh_result);
1242 set_buffer_delay(bh_result);
1243 }
1244 }
1245
1246
1247
1248
1249
1250 if (direct || size > (1 << inode->i_blkbits)) {
1251 xfs_off_t mapping_size;
1252
1253 mapping_size = imap.br_startoff + imap.br_blockcount - iblock;
1254 mapping_size <<= inode->i_blkbits;
1255
1256 ASSERT(mapping_size > 0);
1257 if (mapping_size > size)
1258 mapping_size = size;
1259 if (mapping_size > LONG_MAX)
1260 mapping_size = LONG_MAX;
1261
1262 bh_result->b_size = mapping_size;
1263 }
1264
1265 return 0;
1266
1267out_unlock:
1268 xfs_iunlock(ip, lockmode);
1269 return -error;
1270}
1271
1272int
1273xfs_get_blocks(
1274 struct inode *inode,
1275 sector_t iblock,
1276 struct buffer_head *bh_result,
1277 int create)
1278{
1279 return __xfs_get_blocks(inode, iblock, bh_result, create, 0);
1280}
1281
1282STATIC int
1283xfs_get_blocks_direct(
1284 struct inode *inode,
1285 sector_t iblock,
1286 struct buffer_head *bh_result,
1287 int create)
1288{
1289 return __xfs_get_blocks(inode, iblock, bh_result, create, 1);
1290}
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303STATIC void
1304xfs_end_io_direct_write(
1305 struct kiocb *iocb,
1306 loff_t offset,
1307 ssize_t size,
1308 void *private,
1309 int ret,
1310 bool is_async)
1311{
1312 struct xfs_ioend *ioend = iocb->private;
1313
1314
1315
1316
1317
1318
1319 iocb->private = NULL;
1320
1321 ioend->io_offset = offset;
1322 ioend->io_size = size;
1323 if (private && size > 0)
1324 ioend->io_type = IO_UNWRITTEN;
1325
1326 if (is_async) {
1327
1328
1329
1330
1331
1332 if (ioend->io_type == IO_UNWRITTEN) {
1333 ioend->io_iocb = iocb;
1334 ioend->io_result = ret;
1335 } else {
1336 aio_complete(iocb, ret, 0);
1337 }
1338 xfs_finish_ioend(ioend);
1339 } else {
1340 xfs_finish_ioend_sync(ioend);
1341 }
1342}
1343
1344STATIC ssize_t
1345xfs_vm_direct_IO(
1346 int rw,
1347 struct kiocb *iocb,
1348 const struct iovec *iov,
1349 loff_t offset,
1350 unsigned long nr_segs)
1351{
1352 struct inode *inode = iocb->ki_filp->f_mapping->host;
1353 struct block_device *bdev = xfs_find_bdev_for_inode(inode);
1354 ssize_t ret;
1355
1356 if (rw & WRITE) {
1357 iocb->private = xfs_alloc_ioend(inode, IO_DIRECT);
1358
1359 ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
1360 offset, nr_segs,
1361 xfs_get_blocks_direct,
1362 xfs_end_io_direct_write, NULL, 0);
1363 if (ret != -EIOCBQUEUED && iocb->private)
1364 xfs_destroy_ioend(iocb->private);
1365 } else {
1366 ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
1367 offset, nr_segs,
1368 xfs_get_blocks_direct,
1369 NULL, NULL, 0);
1370 }
1371
1372 return ret;
1373}
1374
1375STATIC void
1376xfs_vm_write_failed(
1377 struct address_space *mapping,
1378 loff_t to)
1379{
1380 struct inode *inode = mapping->host;
1381
1382 if (to > inode->i_size) {
1383
1384
1385
1386
1387
1388
1389
1390
1391 struct xfs_inode *ip = XFS_I(inode);
1392 xfs_fileoff_t start_fsb;
1393 xfs_fileoff_t end_fsb;
1394 int error;
1395
1396 truncate_pagecache(inode, to, inode->i_size);
1397
1398
1399
1400
1401
1402 start_fsb = XFS_B_TO_FSB(ip->i_mount, inode->i_size) + 1;
1403 end_fsb = XFS_B_TO_FSB(ip->i_mount, to);
1404 if (end_fsb <= start_fsb)
1405 return;
1406
1407 xfs_ilock(ip, XFS_ILOCK_EXCL);
1408 error = xfs_bmap_punch_delalloc_range(ip, start_fsb,
1409 end_fsb - start_fsb);
1410 if (error) {
1411
1412 if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
1413 xfs_alert(ip->i_mount,
1414 "xfs_vm_write_failed: unable to clean up ino %lld",
1415 ip->i_ino);
1416 }
1417 }
1418 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1419 }
1420}
1421
1422STATIC int
1423xfs_vm_write_begin(
1424 struct file *file,
1425 struct address_space *mapping,
1426 loff_t pos,
1427 unsigned len,
1428 unsigned flags,
1429 struct page **pagep,
1430 void **fsdata)
1431{
1432 int ret;
1433
1434 ret = block_write_begin(mapping, pos, len, flags | AOP_FLAG_NOFS,
1435 pagep, xfs_get_blocks);
1436 if (unlikely(ret))
1437 xfs_vm_write_failed(mapping, pos + len);
1438 return ret;
1439}
1440
1441STATIC int
1442xfs_vm_write_end(
1443 struct file *file,
1444 struct address_space *mapping,
1445 loff_t pos,
1446 unsigned len,
1447 unsigned copied,
1448 struct page *page,
1449 void *fsdata)
1450{
1451 int ret;
1452
1453 ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
1454 if (unlikely(ret < len))
1455 xfs_vm_write_failed(mapping, pos + len);
1456 return ret;
1457}
1458
1459STATIC sector_t
1460xfs_vm_bmap(
1461 struct address_space *mapping,
1462 sector_t block)
1463{
1464 struct inode *inode = (struct inode *)mapping->host;
1465 struct xfs_inode *ip = XFS_I(inode);
1466
1467 trace_xfs_vm_bmap(XFS_I(inode));
1468 xfs_ilock(ip, XFS_IOLOCK_SHARED);
1469 xfs_flush_pages(ip, (xfs_off_t)0, -1, 0, FI_REMAPF);
1470 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
1471 return generic_block_bmap(mapping, block, xfs_get_blocks);
1472}
1473
1474STATIC int
1475xfs_vm_readpage(
1476 struct file *unused,
1477 struct page *page)
1478{
1479 return mpage_readpage(page, xfs_get_blocks);
1480}
1481
1482STATIC int
1483xfs_vm_readpages(
1484 struct file *unused,
1485 struct address_space *mapping,
1486 struct list_head *pages,
1487 unsigned nr_pages)
1488{
1489 return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
1490}
1491
1492const struct address_space_operations xfs_address_space_operations = {
1493 .readpage = xfs_vm_readpage,
1494 .readpages = xfs_vm_readpages,
1495 .writepage = xfs_vm_writepage,
1496 .writepages = xfs_vm_writepages,
1497 .releasepage = xfs_vm_releasepage,
1498 .invalidatepage = xfs_vm_invalidatepage,
1499 .write_begin = xfs_vm_write_begin,
1500 .write_end = xfs_vm_write_end,
1501 .bmap = xfs_vm_bmap,
1502 .direct_IO = xfs_vm_direct_IO,
1503 .migratepage = buffer_migrate_page,
1504 .is_partially_uptodate = block_is_partially_uptodate,
1505 .error_remove_page = generic_error_remove_page,
1506};
1507