2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
25 #include "xfs_trans.h"
26 #include "xfs_dmapi.h"
27 #include "xfs_mount.h"
28 #include "xfs_bmap_btree.h"
29 #include "xfs_alloc_btree.h"
30 #include "xfs_ialloc_btree.h"
31 #include "xfs_dir2_sf.h"
32 #include "xfs_attr_sf.h"
33 #include "xfs_dinode.h"
34 #include "xfs_inode.h"
35 #include "xfs_alloc.h"
36 #include "xfs_btree.h"
37 #include "xfs_error.h"
39 #include "xfs_iomap.h"
40 #include "xfs_vnodeops.h"
41 #include <linux/mpage.h>
42 #include <linux/pagevec.h>
43 #include <linux/writeback.h>
52 struct buffer_head *bh, *head;
54 *delalloc = *unmapped = *unwritten = 0;
56 bh = head = page_buffers(page);
58 if (buffer_uptodate(bh) && !buffer_mapped(bh))
60 else if (buffer_unwritten(bh))
62 else if (buffer_delay(bh))
64 } while ((bh = bh->b_this_page) != head);
67 #if defined(XFS_RW_TRACE)
76 bhv_vnode_t *vp = vn_from_inode(inode);
77 loff_t isize = i_size_read(inode);
78 loff_t offset = page_offset(page);
79 int delalloc = -1, unmapped = -1, unwritten = -1;
81 if (page_has_buffers(page))
82 xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
88 ktrace_enter(ip->i_rwtrace,
89 (void *)((unsigned long)tag),
94 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
95 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
96 (void *)((unsigned long)((isize >> 32) & 0xffffffff)),
97 (void *)((unsigned long)(isize & 0xffffffff)),
98 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
99 (void *)((unsigned long)(offset & 0xffffffff)),
100 (void *)((unsigned long)delalloc),
101 (void *)((unsigned long)unmapped),
102 (void *)((unsigned long)unwritten),
103 (void *)((unsigned long)current_pid()),
107 #define xfs_page_trace(tag, inode, page, pgoff)
111 * Schedule IO completion handling on a xfsdatad if this was
112 * the final hold on this ioend. If we are asked to wait,
113 * flush the workqueue.
120 if (atomic_dec_and_test(&ioend->io_remaining)) {
121 queue_work(xfsdatad_workqueue, &ioend->io_work);
123 flush_workqueue(xfsdatad_workqueue);
128 * We're now finished for good with this ioend structure.
129 * Update the page state via the associated buffer_heads,
130 * release holds on the inode and bio, and finally free
131 * up memory. Do not use the ioend after this.
137 struct buffer_head *bh, *next;
139 for (bh = ioend->io_buffer_head; bh; bh = next) {
140 next = bh->b_private;
141 bh->b_end_io(bh, !ioend->io_error);
143 if (unlikely(ioend->io_error))
144 vn_ioerror(ioend->io_vnode, ioend->io_error, __FILE__,__LINE__);
145 vn_iowake(ioend->io_vnode);
146 mempool_free(ioend, xfs_ioend_pool);
150 * Update on-disk file size now that data has been written to disk.
151 * The current in-memory file size is i_size. If a write is beyond
152 * eof io_new_size will be the intended file size until i_size is
153 * updated. If this write does not extend all the way to the valid
154 * file size then restrict this update to the end of the write.
164 ip = xfs_vtoi(ioend->io_vnode);
168 ASSERT((ip->i_d.di_mode & S_IFMT) == S_IFREG);
169 ASSERT(ioend->io_type != IOMAP_READ);
171 if (unlikely(ioend->io_error))
174 bsize = ioend->io_offset + ioend->io_size;
176 xfs_ilock(ip, XFS_ILOCK_EXCL);
178 isize = MAX(ip->i_size, ip->i_iocore.io_new_size);
179 isize = MIN(isize, bsize);
181 if (ip->i_d.di_size < isize) {
182 ip->i_d.di_size = isize;
183 ip->i_update_core = 1;
184 ip->i_update_size = 1;
185 mark_inode_dirty_sync(vn_to_inode(ioend->io_vnode));
188 xfs_iunlock(ip, XFS_ILOCK_EXCL);
192 * Buffered IO write completion for delayed allocate extents.
195 xfs_end_bio_delalloc(
196 struct work_struct *work)
199 container_of(work, xfs_ioend_t, io_work);
201 xfs_setfilesize(ioend);
202 xfs_destroy_ioend(ioend);
206 * Buffered IO write completion for regular, written extents.
210 struct work_struct *work)
213 container_of(work, xfs_ioend_t, io_work);
215 xfs_setfilesize(ioend);
216 xfs_destroy_ioend(ioend);
220 * IO write completion for unwritten extents.
222 * Issue transactions to convert a buffer range from unwritten
223 * to written extents.
226 xfs_end_bio_unwritten(
227 struct work_struct *work)
230 container_of(work, xfs_ioend_t, io_work);
231 bhv_vnode_t *vp = ioend->io_vnode;
232 xfs_off_t offset = ioend->io_offset;
233 size_t size = ioend->io_size;
235 if (likely(!ioend->io_error)) {
236 xfs_bmap(xfs_vtoi(vp), offset, size,
237 BMAPI_UNWRITTEN, NULL, NULL);
238 xfs_setfilesize(ioend);
240 xfs_destroy_ioend(ioend);
244 * IO read completion for regular, written extents.
248 struct work_struct *work)
251 container_of(work, xfs_ioend_t, io_work);
253 xfs_destroy_ioend(ioend);
257 * Allocate and initialise an IO completion structure.
258 * We need to track unwritten extent write completion here initially.
259 * We'll need to extend this for updating the ondisk inode size later
269 ioend = mempool_alloc(xfs_ioend_pool, GFP_NOFS);
272 * Set the count to 1 initially, which will prevent an I/O
273 * completion callback from happening before we have started
274 * all the I/O from calling the completion routine too early.
276 atomic_set(&ioend->io_remaining, 1);
278 ioend->io_list = NULL;
279 ioend->io_type = type;
280 ioend->io_vnode = vn_from_inode(inode);
281 ioend->io_buffer_head = NULL;
282 ioend->io_buffer_tail = NULL;
283 atomic_inc(&ioend->io_vnode->v_iocount);
284 ioend->io_offset = 0;
287 if (type == IOMAP_UNWRITTEN)
288 INIT_WORK(&ioend->io_work, xfs_end_bio_unwritten);
289 else if (type == IOMAP_DELAY)
290 INIT_WORK(&ioend->io_work, xfs_end_bio_delalloc);
291 else if (type == IOMAP_READ)
292 INIT_WORK(&ioend->io_work, xfs_end_bio_read);
294 INIT_WORK(&ioend->io_work, xfs_end_bio_written);
307 xfs_inode_t *ip = XFS_I(inode);
308 int error, nmaps = 1;
310 error = xfs_bmap(ip, offset, count,
311 flags, mapp, &nmaps);
312 if (!error && (flags & (BMAPI_WRITE|BMAPI_ALLOCATE)))
313 xfs_iflags_set(ip, XFS_IMODIFIED);
322 return offset >= iomapp->iomap_offset &&
323 offset < iomapp->iomap_offset + iomapp->iomap_bsize;
327 * BIO completion handler for buffered IO.
332 unsigned int bytes_done,
335 xfs_ioend_t *ioend = bio->bi_private;
340 ASSERT(atomic_read(&bio->bi_cnt) >= 1);
341 ioend->io_error = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : error;
343 /* Toss bio and pass work off to an xfsdatad thread */
344 bio->bi_private = NULL;
345 bio->bi_end_io = NULL;
348 xfs_finish_ioend(ioend, 0);
353 xfs_submit_ioend_bio(
357 atomic_inc(&ioend->io_remaining);
359 bio->bi_private = ioend;
360 bio->bi_end_io = xfs_end_bio;
362 submit_bio(WRITE, bio);
363 ASSERT(!bio_flagged(bio, BIO_EOPNOTSUPP));
369 struct buffer_head *bh)
372 int nvecs = bio_get_nr_vecs(bh->b_bdev);
375 bio = bio_alloc(GFP_NOIO, nvecs);
379 ASSERT(bio->bi_private == NULL);
380 bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
381 bio->bi_bdev = bh->b_bdev;
387 xfs_start_buffer_writeback(
388 struct buffer_head *bh)
390 ASSERT(buffer_mapped(bh));
391 ASSERT(buffer_locked(bh));
392 ASSERT(!buffer_delay(bh));
393 ASSERT(!buffer_unwritten(bh));
395 mark_buffer_async_write(bh);
396 set_buffer_uptodate(bh);
397 clear_buffer_dirty(bh);
401 xfs_start_page_writeback(
403 struct writeback_control *wbc,
407 ASSERT(PageLocked(page));
408 ASSERT(!PageWriteback(page));
410 clear_page_dirty_for_io(page);
411 set_page_writeback(page);
414 end_page_writeback(page);
415 wbc->pages_skipped++; /* We didn't write this page */
419 static inline int bio_add_buffer(struct bio *bio, struct buffer_head *bh)
421 return bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
425 * Submit all of the bios for all of the ioends we have saved up, covering the
426 * initial writepage page and also any probed pages.
428 * Because we may have multiple ioends spanning a page, we need to start
429 * writeback on all the buffers before we submit them for I/O. If we mark the
430 * buffers as we got, then we can end up with a page that only has buffers
431 * marked async write and I/O complete on can occur before we mark the other
432 * buffers async write.
434 * The end result of this is that we trip a bug in end_page_writeback() because
435 * we call it twice for the one page as the code in end_buffer_async_write()
436 * assumes that all buffers on the page are started at the same time.
438 * The fix is two passes across the ioend list - one to start writeback on the
439 * buffer_heads, and then submit them for I/O on the second pass.
445 xfs_ioend_t *head = ioend;
447 struct buffer_head *bh;
449 sector_t lastblock = 0;
451 /* Pass 1 - start writeback */
453 next = ioend->io_list;
454 for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
455 xfs_start_buffer_writeback(bh);
457 } while ((ioend = next) != NULL);
459 /* Pass 2 - submit I/O */
462 next = ioend->io_list;
465 for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
469 bio = xfs_alloc_ioend_bio(bh);
470 } else if (bh->b_blocknr != lastblock + 1) {
471 xfs_submit_ioend_bio(ioend, bio);
475 if (bio_add_buffer(bio, bh) != bh->b_size) {
476 xfs_submit_ioend_bio(ioend, bio);
480 lastblock = bh->b_blocknr;
483 xfs_submit_ioend_bio(ioend, bio);
484 xfs_finish_ioend(ioend, 0);
485 } while ((ioend = next) != NULL);
489 * Cancel submission of all buffer_heads so far in this endio.
490 * Toss the endio too. Only ever called for the initial page
491 * in a writepage request, so only ever one page.
498 struct buffer_head *bh, *next_bh;
501 next = ioend->io_list;
502 bh = ioend->io_buffer_head;
504 next_bh = bh->b_private;
505 clear_buffer_async_write(bh);
507 } while ((bh = next_bh) != NULL);
509 vn_iowake(ioend->io_vnode);
510 mempool_free(ioend, xfs_ioend_pool);
511 } while ((ioend = next) != NULL);
515 * Test to see if we've been building up a completion structure for
516 * earlier buffers -- if so, we try to append to this ioend if we
517 * can, otherwise we finish off any current ioend and start another.
518 * Return true if we've finished the given ioend.
523 struct buffer_head *bh,
526 xfs_ioend_t **result,
529 xfs_ioend_t *ioend = *result;
531 if (!ioend || need_ioend || type != ioend->io_type) {
532 xfs_ioend_t *previous = *result;
534 ioend = xfs_alloc_ioend(inode, type);
535 ioend->io_offset = offset;
536 ioend->io_buffer_head = bh;
537 ioend->io_buffer_tail = bh;
539 previous->io_list = ioend;
542 ioend->io_buffer_tail->b_private = bh;
543 ioend->io_buffer_tail = bh;
546 bh->b_private = NULL;
547 ioend->io_size += bh->b_size;
552 struct buffer_head *bh,
559 ASSERT(mp->iomap_bn != IOMAP_DADDR_NULL);
561 bn = (mp->iomap_bn >> (block_bits - BBSHIFT)) +
562 ((offset - mp->iomap_offset) >> block_bits);
564 ASSERT(bn || (mp->iomap_flags & IOMAP_REALTIME));
567 set_buffer_mapped(bh);
572 struct buffer_head *bh,
577 ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE));
578 ASSERT(!(iomapp->iomap_flags & IOMAP_DELAY));
581 xfs_map_buffer(bh, iomapp, offset, block_bits);
582 bh->b_bdev = iomapp->iomap_target->bt_bdev;
583 set_buffer_mapped(bh);
584 clear_buffer_delay(bh);
585 clear_buffer_unwritten(bh);
589 * Look for a page at index that is suitable for clustering.
594 unsigned int pg_offset,
599 if (PageWriteback(page))
602 if (page->mapping && PageDirty(page)) {
603 if (page_has_buffers(page)) {
604 struct buffer_head *bh, *head;
606 bh = head = page_buffers(page);
608 if (!buffer_uptodate(bh))
610 if (mapped != buffer_mapped(bh))
613 if (ret >= pg_offset)
615 } while ((bh = bh->b_this_page) != head);
617 ret = mapped ? 0 : PAGE_CACHE_SIZE;
626 struct page *startpage,
627 struct buffer_head *bh,
628 struct buffer_head *head,
632 pgoff_t tindex, tlast, tloff;
636 /* First sum forwards in this page */
638 if (!buffer_uptodate(bh) || (mapped != buffer_mapped(bh)))
641 } while ((bh = bh->b_this_page) != head);
643 /* if we reached the end of the page, sum forwards in following pages */
644 tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
645 tindex = startpage->index + 1;
647 /* Prune this back to avoid pathological behavior */
648 tloff = min(tlast, startpage->index + 64);
650 pagevec_init(&pvec, 0);
651 while (!done && tindex <= tloff) {
652 unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
654 if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
657 for (i = 0; i < pagevec_count(&pvec); i++) {
658 struct page *page = pvec.pages[i];
659 size_t pg_offset, pg_len = 0;
661 if (tindex == tlast) {
663 i_size_read(inode) & (PAGE_CACHE_SIZE - 1);
669 pg_offset = PAGE_CACHE_SIZE;
671 if (page->index == tindex && !TestSetPageLocked(page)) {
672 pg_len = xfs_probe_page(page, pg_offset, mapped);
685 pagevec_release(&pvec);
693 * Test if a given page is suitable for writing as part of an unwritten
694 * or delayed allocate extent.
701 if (PageWriteback(page))
704 if (page->mapping && page_has_buffers(page)) {
705 struct buffer_head *bh, *head;
708 bh = head = page_buffers(page);
710 if (buffer_unwritten(bh))
711 acceptable = (type == IOMAP_UNWRITTEN);
712 else if (buffer_delay(bh))
713 acceptable = (type == IOMAP_DELAY);
714 else if (buffer_dirty(bh) && buffer_mapped(bh))
715 acceptable = (type == IOMAP_NEW);
718 } while ((bh = bh->b_this_page) != head);
728 * Allocate & map buffers for page given the extent map. Write it out.
729 * except for the original page of a writepage, this is called on
730 * delalloc/unwritten pages only, for the original page it is possible
731 * that the page has no mapping at all.
739 xfs_ioend_t **ioendp,
740 struct writeback_control *wbc,
744 struct buffer_head *bh, *head;
745 xfs_off_t end_offset;
746 unsigned long p_offset;
748 int bbits = inode->i_blkbits;
750 int count = 0, done = 0, uptodate = 1;
751 xfs_off_t offset = page_offset(page);
753 if (page->index != tindex)
755 if (TestSetPageLocked(page))
757 if (PageWriteback(page))
758 goto fail_unlock_page;
759 if (page->mapping != inode->i_mapping)
760 goto fail_unlock_page;
761 if (!xfs_is_delayed_page(page, (*ioendp)->io_type))
762 goto fail_unlock_page;
765 * page_dirty is initially a count of buffers on the page before
766 * EOF and is decremented as we move each into a cleanable state.
770 * End offset is the highest offset that this page should represent.
771 * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
772 * will evaluate non-zero and be less than PAGE_CACHE_SIZE and
773 * hence give us the correct page_dirty count. On any other page,
774 * it will be zero and in that case we need page_dirty to be the
775 * count of buffers on the page.
777 end_offset = min_t(unsigned long long,
778 (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
781 len = 1 << inode->i_blkbits;
782 p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
784 p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
785 page_dirty = p_offset / len;
787 bh = head = page_buffers(page);
789 if (offset >= end_offset)
791 if (!buffer_uptodate(bh))
793 if (!(PageUptodate(page) || buffer_uptodate(bh))) {
798 if (buffer_unwritten(bh) || buffer_delay(bh)) {
799 if (buffer_unwritten(bh))
800 type = IOMAP_UNWRITTEN;
804 if (!xfs_iomap_valid(mp, offset)) {
809 ASSERT(!(mp->iomap_flags & IOMAP_HOLE));
810 ASSERT(!(mp->iomap_flags & IOMAP_DELAY));
812 xfs_map_at_offset(bh, offset, bbits, mp);
814 xfs_add_to_ioend(inode, bh, offset,
817 set_buffer_dirty(bh);
819 mark_buffer_dirty(bh);
825 if (buffer_mapped(bh) && all_bh && startio) {
827 xfs_add_to_ioend(inode, bh, offset,
835 } while (offset += len, (bh = bh->b_this_page) != head);
837 if (uptodate && bh == head)
838 SetPageUptodate(page);
842 struct backing_dev_info *bdi;
844 bdi = inode->i_mapping->backing_dev_info;
846 if (bdi_write_congested(bdi)) {
847 wbc->encountered_congestion = 1;
849 } else if (wbc->nr_to_write <= 0) {
853 xfs_start_page_writeback(page, wbc, !page_dirty, count);
864 * Convert & write out a cluster of pages in the same extent as defined
865 * by mp and following the start page.
872 xfs_ioend_t **ioendp,
873 struct writeback_control *wbc,
881 pagevec_init(&pvec, 0);
882 while (!done && tindex <= tlast) {
883 unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
885 if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
888 for (i = 0; i < pagevec_count(&pvec); i++) {
889 done = xfs_convert_page(inode, pvec.pages[i], tindex++,
890 iomapp, ioendp, wbc, startio, all_bh);
895 pagevec_release(&pvec);
901 * Calling this without startio set means we are being asked to make a dirty
902 * page ready for freeing it's buffers. When called with startio set then
903 * we are coming from writepage.
905 * When called with startio set it is important that we write the WHOLE
907 * The bh->b_state's cannot know if any of the blocks or which block for
908 * that matter are dirty due to mmap writes, and therefore bh uptodate is
909 * only valid if the page itself isn't completely uptodate. Some layers
910 * may clear the page dirty flag prior to calling write page, under the
911 * assumption the entire page will be written out; by not writing out the
912 * whole page the page can be reused before all valid dirty data is
913 * written out. Note: in the case of a page that has been dirty'd by
914 * mapwrite and but partially setup by block_prepare_write the
915 * bh->b_states's will not agree and only ones setup by BPW/BCW will have
916 * valid state, thus the whole page must be written out thing.
920 xfs_page_state_convert(
923 struct writeback_control *wbc,
925 int unmapped) /* also implies page uptodate */
927 struct buffer_head *bh, *head;
929 xfs_ioend_t *ioend = NULL, *iohead = NULL;
931 unsigned long p_offset = 0;
933 __uint64_t end_offset;
934 pgoff_t end_index, last_index, tlast;
936 int flags, err, iomap_valid = 0, uptodate = 1;
937 int page_dirty, count = 0;
939 int all_bh = unmapped;
942 if (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking)
943 trylock |= BMAPI_TRYLOCK;
946 /* Is this page beyond the end of the file? */
947 offset = i_size_read(inode);
948 end_index = offset >> PAGE_CACHE_SHIFT;
949 last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
950 if (page->index >= end_index) {
951 if ((page->index >= end_index + 1) ||
952 !(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
960 * page_dirty is initially a count of buffers on the page before
961 * EOF and is decremented as we move each into a cleanable state.
965 * End offset is the highest offset that this page should represent.
966 * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
967 * will evaluate non-zero and be less than PAGE_CACHE_SIZE and
968 * hence give us the correct page_dirty count. On any other page,
969 * it will be zero and in that case we need page_dirty to be the
970 * count of buffers on the page.
972 end_offset = min_t(unsigned long long,
973 (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT, offset);
974 len = 1 << inode->i_blkbits;
975 p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
977 p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
978 page_dirty = p_offset / len;
980 bh = head = page_buffers(page);
981 offset = page_offset(page);
985 /* TODO: cleanup count and page_dirty */
988 if (offset >= end_offset)
990 if (!buffer_uptodate(bh))
992 if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio) {
994 * the iomap is actually still valid, but the ioend
995 * isn't. shouldn't happen too often.
1002 iomap_valid = xfs_iomap_valid(&iomap, offset);
1005 * First case, map an unwritten extent and prepare for
1006 * extent state conversion transaction on completion.
1008 * Second case, allocate space for a delalloc buffer.
1009 * We can return EAGAIN here in the release page case.
1011 * Third case, an unmapped buffer was found, and we are
1012 * in a path where we need to write the whole page out.
1014 if (buffer_unwritten(bh) || buffer_delay(bh) ||
1015 ((buffer_uptodate(bh) || PageUptodate(page)) &&
1016 !buffer_mapped(bh) && (unmapped || startio))) {
1020 * Make sure we don't use a read-only iomap
1022 if (flags == BMAPI_READ)
1025 if (buffer_unwritten(bh)) {
1026 type = IOMAP_UNWRITTEN;
1027 flags = BMAPI_WRITE | BMAPI_IGNSTATE;
1028 } else if (buffer_delay(bh)) {
1030 flags = BMAPI_ALLOCATE | trylock;
1033 flags = BMAPI_WRITE | BMAPI_MMAP;
1038 * if we didn't have a valid mapping then we
1039 * need to ensure that we put the new mapping
1040 * in a new ioend structure. This needs to be
1041 * done to ensure that the ioends correctly
1042 * reflect the block mappings at io completion
1043 * for unwritten extent conversion.
1046 if (type == IOMAP_NEW) {
1047 size = xfs_probe_cluster(inode,
1053 err = xfs_map_blocks(inode, offset, size,
1057 iomap_valid = xfs_iomap_valid(&iomap, offset);
1060 xfs_map_at_offset(bh, offset,
1061 inode->i_blkbits, &iomap);
1063 xfs_add_to_ioend(inode, bh, offset,
1067 set_buffer_dirty(bh);
1069 mark_buffer_dirty(bh);
1074 } else if (buffer_uptodate(bh) && startio) {
1076 * we got here because the buffer is already mapped.
1077 * That means it must already have extents allocated
1078 * underneath it. Map the extent by reading it.
1080 if (!iomap_valid || flags != BMAPI_READ) {
1082 size = xfs_probe_cluster(inode, page, bh,
1084 err = xfs_map_blocks(inode, offset, size,
1088 iomap_valid = xfs_iomap_valid(&iomap, offset);
1092 * We set the type to IOMAP_NEW in case we are doing a
1093 * small write at EOF that is extending the file but
1094 * without needing an allocation. We need to update the
1095 * file size on I/O completion in this case so it is
1096 * the same case as having just allocated a new extent
1097 * that we are writing into for the first time.
1100 if (!test_and_set_bit(BH_Lock, &bh->b_state)) {
1101 ASSERT(buffer_mapped(bh));
1104 xfs_add_to_ioend(inode, bh, offset, type,
1105 &ioend, !iomap_valid);
1111 } else if ((buffer_uptodate(bh) || PageUptodate(page)) &&
1112 (unmapped || startio)) {
1119 } while (offset += len, ((bh = bh->b_this_page) != head));
1121 if (uptodate && bh == head)
1122 SetPageUptodate(page);
1125 xfs_start_page_writeback(page, wbc, 1, count);
1127 if (ioend && iomap_valid) {
1128 offset = (iomap.iomap_offset + iomap.iomap_bsize - 1) >>
1130 tlast = min_t(pgoff_t, offset, last_index);
1131 xfs_cluster_write(inode, page->index + 1, &iomap, &ioend,
1132 wbc, startio, all_bh, tlast);
1136 xfs_submit_ioend(iohead);
1142 xfs_cancel_ioend(iohead);
1145 * If it's delalloc and we have nowhere to put it,
1146 * throw it away, unless the lower layers told
1149 if (err != -EAGAIN) {
1151 block_invalidatepage(page, 0);
1152 ClearPageUptodate(page);
1158 * writepage: Called from one of two places:
1160 * 1. we are flushing a delalloc buffer head.
1162 * 2. we are writing out a dirty page. Typically the page dirty
1163 * state is cleared before we get here. In this case is it
1164 * conceivable we have no buffer heads.
1166 * For delalloc space on the page we need to allocate space and
1167 * flush it. For unmapped buffer heads on the page we should
1168 * allocate space if the page is uptodate. For any other dirty
1169 * buffer heads on the page we should flush them.
1171 * If we detect that a transaction would be required to flush
1172 * the page, we have to check the process flags first, if we
1173 * are already in a transaction or disk I/O during allocations
1174 * is off, we need to fail the writepage and redirty the page.
1180 struct writeback_control *wbc)
1184 int delalloc, unmapped, unwritten;
1185 struct inode *inode = page->mapping->host;
1187 xfs_page_trace(XFS_WRITEPAGE_ENTER, inode, page, 0);
1190 * We need a transaction if:
1191 * 1. There are delalloc buffers on the page
1192 * 2. The page is uptodate and we have unmapped buffers
1193 * 3. The page is uptodate and we have no buffers
1194 * 4. There are unwritten buffers on the page
1197 if (!page_has_buffers(page)) {
1201 xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
1202 if (!PageUptodate(page))
1204 need_trans = delalloc + unmapped + unwritten;
1208 * If we need a transaction and the process flags say
1209 * we are already in a transaction, or no IO is allowed
1210 * then mark the page dirty again and leave the page
1213 if (current_test_flags(PF_FSTRANS) && need_trans)
1217 * Delay hooking up buffer heads until we have
1218 * made our go/no-go decision.
1220 if (!page_has_buffers(page))
1221 create_empty_buffers(page, 1 << inode->i_blkbits, 0);
1224 * Convert delayed allocate, unwritten or unmapped space
1225 * to real space and flush out to disk.
1227 error = xfs_page_state_convert(inode, page, wbc, 1, unmapped);
1228 if (error == -EAGAIN)
1230 if (unlikely(error < 0))
1236 redirty_page_for_writepage(wbc, page);
1246 struct address_space *mapping,
1247 struct writeback_control *wbc)
1249 xfs_iflags_clear(XFS_I(mapping->host), XFS_ITRUNCATED);
1250 return generic_writepages(mapping, wbc);
1254 * Called to move a page into cleanable state - and from there
1255 * to be released. Possibly the page is already clean. We always
1256 * have buffer heads in this call.
1258 * Returns 0 if the page is ok to release, 1 otherwise.
1260 * Possible scenarios are:
1262 * 1. We are being called to release a page which has been written
1263 * to via regular I/O. buffer heads will be dirty and possibly
1264 * delalloc. If no delalloc buffer heads in this case then we
1265 * can just return zero.
1267 * 2. We are called to release a page which has been written via
1268 * mmap, all we need to do is ensure there is no delalloc
1269 * state in the buffer heads, if not we can let the caller
1270 * free them and we should come back later via writepage.
1277 struct inode *inode = page->mapping->host;
1278 int dirty, delalloc, unmapped, unwritten;
1279 struct writeback_control wbc = {
1280 .sync_mode = WB_SYNC_ALL,
1284 xfs_page_trace(XFS_RELEASEPAGE_ENTER, inode, page, 0);
1286 if (!page_has_buffers(page))
1289 xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
1290 if (!delalloc && !unwritten)
1293 if (!(gfp_mask & __GFP_FS))
1296 /* If we are already inside a transaction or the thread cannot
1297 * do I/O, we cannot release this page.
1299 if (current_test_flags(PF_FSTRANS))
1303 * Convert delalloc space to real space, do not flush the
1304 * data out to disk, that will be done by the caller.
1305 * Never need to allocate space here - we will always
1306 * come back to writepage in that case.
1308 dirty = xfs_page_state_convert(inode, page, &wbc, 0, 0);
1309 if (dirty == 0 && !unwritten)
1314 return try_to_free_buffers(page);
1319 struct inode *inode,
1321 struct buffer_head *bh_result,
1324 bmapi_flags_t flags)
1332 offset = (xfs_off_t)iblock << inode->i_blkbits;
1333 ASSERT(bh_result->b_size >= (1 << inode->i_blkbits));
1334 size = bh_result->b_size;
1335 error = xfs_bmap(XFS_I(inode), offset, size,
1336 create ? flags : BMAPI_READ, &iomap, &niomap);
1342 if (iomap.iomap_bn != IOMAP_DADDR_NULL) {
1344 * For unwritten extents do not report a disk address on
1345 * the read case (treat as if we're reading into a hole).
1347 if (create || !(iomap.iomap_flags & IOMAP_UNWRITTEN)) {
1348 xfs_map_buffer(bh_result, &iomap, offset,
1351 if (create && (iomap.iomap_flags & IOMAP_UNWRITTEN)) {
1353 bh_result->b_private = inode;
1354 set_buffer_unwritten(bh_result);
1359 * If this is a realtime file, data may be on a different device.
1360 * to that pointed to from the buffer_head b_bdev currently.
1362 bh_result->b_bdev = iomap.iomap_target->bt_bdev;
1365 * If we previously allocated a block out beyond eof and we are now
1366 * coming back to use it then we will need to flag it as new even if it
1367 * has a disk address.
1369 * With sub-block writes into unwritten extents we also need to mark
1370 * the buffer as new so that the unwritten parts of the buffer gets
1374 ((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) ||
1375 (offset >= i_size_read(inode)) ||
1376 (iomap.iomap_flags & (IOMAP_NEW|IOMAP_UNWRITTEN))))
1377 set_buffer_new(bh_result);
1379 if (iomap.iomap_flags & IOMAP_DELAY) {
1382 set_buffer_uptodate(bh_result);
1383 set_buffer_mapped(bh_result);
1384 set_buffer_delay(bh_result);
1388 if (direct || size > (1 << inode->i_blkbits)) {
1389 ASSERT(iomap.iomap_bsize - iomap.iomap_delta > 0);
1390 offset = min_t(xfs_off_t,
1391 iomap.iomap_bsize - iomap.iomap_delta, size);
1392 bh_result->b_size = (ssize_t)min_t(xfs_off_t, LONG_MAX, offset);
1400 struct inode *inode,
1402 struct buffer_head *bh_result,
1405 return __xfs_get_blocks(inode, iblock,
1406 bh_result, create, 0, BMAPI_WRITE);
1410 xfs_get_blocks_direct(
1411 struct inode *inode,
1413 struct buffer_head *bh_result,
1416 return __xfs_get_blocks(inode, iblock,
1417 bh_result, create, 1, BMAPI_WRITE|BMAPI_DIRECT);
1427 xfs_ioend_t *ioend = iocb->private;
1430 * Non-NULL private data means we need to issue a transaction to
1431 * convert a range from unwritten to written extents. This needs
1432 * to happen from process context but aio+dio I/O completion
1433 * happens from irq context so we need to defer it to a workqueue.
1434 * This is not necessary for synchronous direct I/O, but we do
1435 * it anyway to keep the code uniform and simpler.
1437 * Well, if only it were that simple. Because synchronous direct I/O
1438 * requires extent conversion to occur *before* we return to userspace,
1439 * we have to wait for extent conversion to complete. Look at the
1440 * iocb that has been passed to us to determine if this is AIO or
1441 * not. If it is synchronous, tell xfs_finish_ioend() to kick the
1442 * workqueue and wait for it to complete.
1444 * The core direct I/O code might be changed to always call the
1445 * completion handler in the future, in which case all this can
1448 ioend->io_offset = offset;
1449 ioend->io_size = size;
1450 if (ioend->io_type == IOMAP_READ) {
1451 xfs_finish_ioend(ioend, 0);
1452 } else if (private && size > 0) {
1453 xfs_finish_ioend(ioend, is_sync_kiocb(iocb));
1456 * A direct I/O write ioend starts it's life in unwritten
1457 * state in case they map an unwritten extent. This write
1458 * didn't map an unwritten extent so switch it's completion
1461 INIT_WORK(&ioend->io_work, xfs_end_bio_written);
1462 xfs_finish_ioend(ioend, 0);
1466 * blockdev_direct_IO can return an error even after the I/O
1467 * completion handler was called. Thus we need to protect
1468 * against double-freeing.
1470 iocb->private = NULL;
1477 const struct iovec *iov,
1479 unsigned long nr_segs)
1481 struct file *file = iocb->ki_filp;
1482 struct inode *inode = file->f_mapping->host;
1488 error = xfs_bmap(XFS_I(inode), offset, 0,
1489 BMAPI_DEVICE, &iomap, &maps);
1494 iocb->private = xfs_alloc_ioend(inode, IOMAP_UNWRITTEN);
1495 ret = blockdev_direct_IO_own_locking(rw, iocb, inode,
1496 iomap.iomap_target->bt_bdev,
1497 iov, offset, nr_segs,
1498 xfs_get_blocks_direct,
1501 iocb->private = xfs_alloc_ioend(inode, IOMAP_READ);
1502 ret = blockdev_direct_IO_no_locking(rw, iocb, inode,
1503 iomap.iomap_target->bt_bdev,
1504 iov, offset, nr_segs,
1505 xfs_get_blocks_direct,
1509 if (unlikely(ret != -EIOCBQUEUED && iocb->private))
1510 xfs_destroy_ioend(iocb->private);
1515 xfs_vm_prepare_write(
1521 return block_prepare_write(page, from, to, xfs_get_blocks);
1526 struct address_space *mapping,
1529 struct inode *inode = (struct inode *)mapping->host;
1530 struct xfs_inode *ip = XFS_I(inode);
1532 vn_trace_entry(vn_from_inode(inode), __FUNCTION__,
1533 (inst_t *)__return_address);
1534 xfs_rwlock(ip, VRWLOCK_READ);
1535 xfs_flush_pages(ip, (xfs_off_t)0, -1, 0, FI_REMAPF);
1536 xfs_rwunlock(ip, VRWLOCK_READ);
1537 return generic_block_bmap(mapping, block, xfs_get_blocks);
1542 struct file *unused,
1545 return mpage_readpage(page, xfs_get_blocks);
1550 struct file *unused,
1551 struct address_space *mapping,
1552 struct list_head *pages,
1555 return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
1559 xfs_vm_invalidatepage(
1561 unsigned long offset)
1563 xfs_page_trace(XFS_INVALIDPAGE_ENTER,
1564 page->mapping->host, page, offset);
1565 block_invalidatepage(page, offset);
1568 const struct address_space_operations xfs_address_space_operations = {
1569 .readpage = xfs_vm_readpage,
1570 .readpages = xfs_vm_readpages,
1571 .writepage = xfs_vm_writepage,
1572 .writepages = xfs_vm_writepages,
1573 .sync_page = block_sync_page,
1574 .releasepage = xfs_vm_releasepage,
1575 .invalidatepage = xfs_vm_invalidatepage,
1576 .prepare_write = xfs_vm_prepare_write,
1577 .commit_write = generic_commit_write,
1578 .bmap = xfs_vm_bmap,
1579 .direct_IO = xfs_vm_direct_IO,
1580 .migratepage = buffer_migrate_page,