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>
47 * Prime number of hash buckets since address is used as the key.
50 #define to_ioend_wq(v) (&xfs_ioend_wq[((unsigned long)v) % NVSYNC])
51 static wait_queue_head_t xfs_ioend_wq[NVSYNC];
58 for (i = 0; i < NVSYNC; i++)
59 init_waitqueue_head(&xfs_ioend_wq[i]);
66 wait_queue_head_t *wq = to_ioend_wq(ip);
68 wait_event(*wq, (atomic_read(&ip->i_iocount) == 0));
75 if (atomic_dec_and_test(&ip->i_iocount))
76 wake_up(to_ioend_wq(ip));
86 struct buffer_head *bh, *head;
88 *delalloc = *unmapped = *unwritten = 0;
90 bh = head = page_buffers(page);
92 if (buffer_uptodate(bh) && !buffer_mapped(bh))
94 else if (buffer_unwritten(bh))
96 else if (buffer_delay(bh))
98 } while ((bh = bh->b_this_page) != head);
101 #if defined(XFS_RW_TRACE)
110 loff_t isize = i_size_read(inode);
111 loff_t offset = page_offset(page);
112 int delalloc = -1, unmapped = -1, unwritten = -1;
114 if (page_has_buffers(page))
115 xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
121 ktrace_enter(ip->i_rwtrace,
122 (void *)((unsigned long)tag),
127 (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
128 (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
129 (void *)((unsigned long)((isize >> 32) & 0xffffffff)),
130 (void *)((unsigned long)(isize & 0xffffffff)),
131 (void *)((unsigned long)((offset >> 32) & 0xffffffff)),
132 (void *)((unsigned long)(offset & 0xffffffff)),
133 (void *)((unsigned long)delalloc),
134 (void *)((unsigned long)unmapped),
135 (void *)((unsigned long)unwritten),
136 (void *)((unsigned long)current_pid()),
140 #define xfs_page_trace(tag, inode, page, pgoff)
143 STATIC struct block_device *
144 xfs_find_bdev_for_inode(
145 struct xfs_inode *ip)
147 struct xfs_mount *mp = ip->i_mount;
149 if (XFS_IS_REALTIME_INODE(ip))
150 return mp->m_rtdev_targp->bt_bdev;
152 return mp->m_ddev_targp->bt_bdev;
156 * We're now finished for good with this ioend structure.
157 * Update the page state via the associated buffer_heads,
158 * release holds on the inode and bio, and finally free
159 * up memory. Do not use the ioend after this.
165 struct buffer_head *bh, *next;
166 struct xfs_inode *ip = XFS_I(ioend->io_inode);
168 for (bh = ioend->io_buffer_head; bh; bh = next) {
169 next = bh->b_private;
170 bh->b_end_io(bh, !ioend->io_error);
174 * Volume managers supporting multiple paths can send back ENODEV
175 * when the final path disappears. In this case continuing to fill
176 * the page cache with dirty data which cannot be written out is
177 * evil, so prevent that.
179 if (unlikely(ioend->io_error == -ENODEV)) {
180 xfs_do_force_shutdown(ip->i_mount, SHUTDOWN_DEVICE_REQ,
185 mempool_free(ioend, xfs_ioend_pool);
189 * If the end of the current ioend is beyond the current EOF,
190 * return the new EOF value, otherwise zero.
196 xfs_inode_t *ip = XFS_I(ioend->io_inode);
200 bsize = ioend->io_offset + ioend->io_size;
201 isize = MAX(ip->i_size, ip->i_new_size);
202 isize = MIN(isize, bsize);
203 return isize > ip->i_d.di_size ? isize : 0;
207 * Update on-disk file size now that data has been written to disk.
208 * The current in-memory file size is i_size. If a write is beyond
209 * eof i_new_size will be the intended file size until i_size is
210 * updated. If this write does not extend all the way to the valid
211 * file size then restrict this update to the end of the write.
218 xfs_inode_t *ip = XFS_I(ioend->io_inode);
221 ASSERT((ip->i_d.di_mode & S_IFMT) == S_IFREG);
222 ASSERT(ioend->io_type != IOMAP_READ);
224 if (unlikely(ioend->io_error))
227 xfs_ilock(ip, XFS_ILOCK_EXCL);
228 isize = xfs_ioend_new_eof(ioend);
230 ip->i_d.di_size = isize;
231 xfs_mark_inode_dirty_sync(ip);
234 xfs_iunlock(ip, XFS_ILOCK_EXCL);
238 * IO write completion.
242 struct work_struct *work)
245 container_of(work, xfs_ioend_t, io_work);
246 struct xfs_inode *ip = XFS_I(ioend->io_inode);
249 * For unwritten extents we need to issue transactions to convert a
250 * range to normal written extens after the data I/O has finished.
252 if (ioend->io_type == IOMAP_UNWRITTEN &&
253 likely(!ioend->io_error && !XFS_FORCED_SHUTDOWN(ip->i_mount))) {
256 error = xfs_iomap_write_unwritten(ip, ioend->io_offset,
259 ioend->io_error = error;
263 * We might have to update the on-disk file size after extending
266 if (ioend->io_type != IOMAP_READ)
267 xfs_setfilesize(ioend);
268 xfs_destroy_ioend(ioend);
272 * Schedule IO completion handling on a xfsdatad if this was
273 * the final hold on this ioend. If we are asked to wait,
274 * flush the workqueue.
281 if (atomic_dec_and_test(&ioend->io_remaining)) {
282 struct workqueue_struct *wq;
284 wq = (ioend->io_type == IOMAP_UNWRITTEN) ?
285 xfsconvertd_workqueue : xfsdatad_workqueue;
286 queue_work(wq, &ioend->io_work);
293 * Allocate and initialise an IO completion structure.
294 * We need to track unwritten extent write completion here initially.
295 * We'll need to extend this for updating the ondisk inode size later
305 ioend = mempool_alloc(xfs_ioend_pool, GFP_NOFS);
308 * Set the count to 1 initially, which will prevent an I/O
309 * completion callback from happening before we have started
310 * all the I/O from calling the completion routine too early.
312 atomic_set(&ioend->io_remaining, 1);
314 ioend->io_list = NULL;
315 ioend->io_type = type;
316 ioend->io_inode = inode;
317 ioend->io_buffer_head = NULL;
318 ioend->io_buffer_tail = NULL;
319 atomic_inc(&XFS_I(ioend->io_inode)->i_iocount);
320 ioend->io_offset = 0;
323 INIT_WORK(&ioend->io_work, xfs_end_io);
337 return -xfs_iomap(XFS_I(inode), offset, count, flags, mapp, &nmaps);
345 return offset >= iomapp->iomap_offset &&
346 offset < iomapp->iomap_offset + iomapp->iomap_bsize;
350 * BIO completion handler for buffered IO.
357 xfs_ioend_t *ioend = bio->bi_private;
359 ASSERT(atomic_read(&bio->bi_cnt) >= 1);
360 ioend->io_error = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : error;
362 /* Toss bio and pass work off to an xfsdatad thread */
363 bio->bi_private = NULL;
364 bio->bi_end_io = NULL;
367 xfs_finish_ioend(ioend, 0);
371 xfs_submit_ioend_bio(
372 struct writeback_control *wbc,
376 atomic_inc(&ioend->io_remaining);
377 bio->bi_private = ioend;
378 bio->bi_end_io = xfs_end_bio;
381 * If the I/O is beyond EOF we mark the inode dirty immediately
382 * but don't update the inode size until I/O completion.
384 if (xfs_ioend_new_eof(ioend))
385 xfs_mark_inode_dirty_sync(XFS_I(ioend->io_inode));
387 submit_bio(wbc->sync_mode == WB_SYNC_ALL ?
388 WRITE_SYNC_PLUG : WRITE, bio);
389 ASSERT(!bio_flagged(bio, BIO_EOPNOTSUPP));
395 struct buffer_head *bh)
398 int nvecs = bio_get_nr_vecs(bh->b_bdev);
401 bio = bio_alloc(GFP_NOIO, nvecs);
405 ASSERT(bio->bi_private == NULL);
406 bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
407 bio->bi_bdev = bh->b_bdev;
413 xfs_start_buffer_writeback(
414 struct buffer_head *bh)
416 ASSERT(buffer_mapped(bh));
417 ASSERT(buffer_locked(bh));
418 ASSERT(!buffer_delay(bh));
419 ASSERT(!buffer_unwritten(bh));
421 mark_buffer_async_write(bh);
422 set_buffer_uptodate(bh);
423 clear_buffer_dirty(bh);
427 xfs_start_page_writeback(
432 ASSERT(PageLocked(page));
433 ASSERT(!PageWriteback(page));
435 clear_page_dirty_for_io(page);
436 set_page_writeback(page);
438 /* If no buffers on the page are to be written, finish it here */
440 end_page_writeback(page);
443 static inline int bio_add_buffer(struct bio *bio, struct buffer_head *bh)
445 return bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
449 * Submit all of the bios for all of the ioends we have saved up, covering the
450 * initial writepage page and also any probed pages.
452 * Because we may have multiple ioends spanning a page, we need to start
453 * writeback on all the buffers before we submit them for I/O. If we mark the
454 * buffers as we got, then we can end up with a page that only has buffers
455 * marked async write and I/O complete on can occur before we mark the other
456 * buffers async write.
458 * The end result of this is that we trip a bug in end_page_writeback() because
459 * we call it twice for the one page as the code in end_buffer_async_write()
460 * assumes that all buffers on the page are started at the same time.
462 * The fix is two passes across the ioend list - one to start writeback on the
463 * buffer_heads, and then submit them for I/O on the second pass.
467 struct writeback_control *wbc,
470 xfs_ioend_t *head = ioend;
472 struct buffer_head *bh;
474 sector_t lastblock = 0;
476 /* Pass 1 - start writeback */
478 next = ioend->io_list;
479 for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
480 xfs_start_buffer_writeback(bh);
482 } while ((ioend = next) != NULL);
484 /* Pass 2 - submit I/O */
487 next = ioend->io_list;
490 for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
494 bio = xfs_alloc_ioend_bio(bh);
495 } else if (bh->b_blocknr != lastblock + 1) {
496 xfs_submit_ioend_bio(wbc, ioend, bio);
500 if (bio_add_buffer(bio, bh) != bh->b_size) {
501 xfs_submit_ioend_bio(wbc, ioend, bio);
505 lastblock = bh->b_blocknr;
508 xfs_submit_ioend_bio(wbc, ioend, bio);
509 xfs_finish_ioend(ioend, 0);
510 } while ((ioend = next) != NULL);
514 * Cancel submission of all buffer_heads so far in this endio.
515 * Toss the endio too. Only ever called for the initial page
516 * in a writepage request, so only ever one page.
523 struct buffer_head *bh, *next_bh;
526 next = ioend->io_list;
527 bh = ioend->io_buffer_head;
529 next_bh = bh->b_private;
530 clear_buffer_async_write(bh);
532 } while ((bh = next_bh) != NULL);
534 xfs_ioend_wake(XFS_I(ioend->io_inode));
535 mempool_free(ioend, xfs_ioend_pool);
536 } while ((ioend = next) != NULL);
540 * Test to see if we've been building up a completion structure for
541 * earlier buffers -- if so, we try to append to this ioend if we
542 * can, otherwise we finish off any current ioend and start another.
543 * Return true if we've finished the given ioend.
548 struct buffer_head *bh,
551 xfs_ioend_t **result,
554 xfs_ioend_t *ioend = *result;
556 if (!ioend || need_ioend || type != ioend->io_type) {
557 xfs_ioend_t *previous = *result;
559 ioend = xfs_alloc_ioend(inode, type);
560 ioend->io_offset = offset;
561 ioend->io_buffer_head = bh;
562 ioend->io_buffer_tail = bh;
564 previous->io_list = ioend;
567 ioend->io_buffer_tail->b_private = bh;
568 ioend->io_buffer_tail = bh;
571 bh->b_private = NULL;
572 ioend->io_size += bh->b_size;
577 struct buffer_head *bh,
584 ASSERT(mp->iomap_bn != IOMAP_DADDR_NULL);
586 bn = (mp->iomap_bn >> (block_bits - BBSHIFT)) +
587 ((offset - mp->iomap_offset) >> block_bits);
589 ASSERT(bn || (mp->iomap_flags & IOMAP_REALTIME));
592 set_buffer_mapped(bh);
597 struct buffer_head *bh,
602 ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE));
603 ASSERT(!(iomapp->iomap_flags & IOMAP_DELAY));
606 xfs_map_buffer(bh, iomapp, offset, block_bits);
607 bh->b_bdev = iomapp->iomap_target->bt_bdev;
608 set_buffer_mapped(bh);
609 clear_buffer_delay(bh);
610 clear_buffer_unwritten(bh);
614 * Look for a page at index that is suitable for clustering.
619 unsigned int pg_offset,
624 if (PageWriteback(page))
627 if (page->mapping && PageDirty(page)) {
628 if (page_has_buffers(page)) {
629 struct buffer_head *bh, *head;
631 bh = head = page_buffers(page);
633 if (!buffer_uptodate(bh))
635 if (mapped != buffer_mapped(bh))
638 if (ret >= pg_offset)
640 } while ((bh = bh->b_this_page) != head);
642 ret = mapped ? 0 : PAGE_CACHE_SIZE;
651 struct page *startpage,
652 struct buffer_head *bh,
653 struct buffer_head *head,
657 pgoff_t tindex, tlast, tloff;
661 /* First sum forwards in this page */
663 if (!buffer_uptodate(bh) || (mapped != buffer_mapped(bh)))
666 } while ((bh = bh->b_this_page) != head);
668 /* if we reached the end of the page, sum forwards in following pages */
669 tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
670 tindex = startpage->index + 1;
672 /* Prune this back to avoid pathological behavior */
673 tloff = min(tlast, startpage->index + 64);
675 pagevec_init(&pvec, 0);
676 while (!done && tindex <= tloff) {
677 unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
679 if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
682 for (i = 0; i < pagevec_count(&pvec); i++) {
683 struct page *page = pvec.pages[i];
684 size_t pg_offset, pg_len = 0;
686 if (tindex == tlast) {
688 i_size_read(inode) & (PAGE_CACHE_SIZE - 1);
694 pg_offset = PAGE_CACHE_SIZE;
696 if (page->index == tindex && trylock_page(page)) {
697 pg_len = xfs_probe_page(page, pg_offset, mapped);
710 pagevec_release(&pvec);
718 * Test if a given page is suitable for writing as part of an unwritten
719 * or delayed allocate extent.
726 if (PageWriteback(page))
729 if (page->mapping && page_has_buffers(page)) {
730 struct buffer_head *bh, *head;
733 bh = head = page_buffers(page);
735 if (buffer_unwritten(bh))
736 acceptable = (type == IOMAP_UNWRITTEN);
737 else if (buffer_delay(bh))
738 acceptable = (type == IOMAP_DELAY);
739 else if (buffer_dirty(bh) && buffer_mapped(bh))
740 acceptable = (type == IOMAP_NEW);
743 } while ((bh = bh->b_this_page) != head);
753 * Allocate & map buffers for page given the extent map. Write it out.
754 * except for the original page of a writepage, this is called on
755 * delalloc/unwritten pages only, for the original page it is possible
756 * that the page has no mapping at all.
764 xfs_ioend_t **ioendp,
765 struct writeback_control *wbc,
769 struct buffer_head *bh, *head;
770 xfs_off_t end_offset;
771 unsigned long p_offset;
773 int bbits = inode->i_blkbits;
775 int count = 0, done = 0, uptodate = 1;
776 xfs_off_t offset = page_offset(page);
778 if (page->index != tindex)
780 if (!trylock_page(page))
782 if (PageWriteback(page))
783 goto fail_unlock_page;
784 if (page->mapping != inode->i_mapping)
785 goto fail_unlock_page;
786 if (!xfs_is_delayed_page(page, (*ioendp)->io_type))
787 goto fail_unlock_page;
790 * page_dirty is initially a count of buffers on the page before
791 * EOF and is decremented as we move each into a cleanable state.
795 * End offset is the highest offset that this page should represent.
796 * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
797 * will evaluate non-zero and be less than PAGE_CACHE_SIZE and
798 * hence give us the correct page_dirty count. On any other page,
799 * it will be zero and in that case we need page_dirty to be the
800 * count of buffers on the page.
802 end_offset = min_t(unsigned long long,
803 (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
806 len = 1 << inode->i_blkbits;
807 p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
809 p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
810 page_dirty = p_offset / len;
812 bh = head = page_buffers(page);
814 if (offset >= end_offset)
816 if (!buffer_uptodate(bh))
818 if (!(PageUptodate(page) || buffer_uptodate(bh))) {
823 if (buffer_unwritten(bh) || buffer_delay(bh)) {
824 if (buffer_unwritten(bh))
825 type = IOMAP_UNWRITTEN;
829 if (!xfs_iomap_valid(mp, offset)) {
834 ASSERT(!(mp->iomap_flags & IOMAP_HOLE));
835 ASSERT(!(mp->iomap_flags & IOMAP_DELAY));
837 xfs_map_at_offset(bh, offset, bbits, mp);
839 xfs_add_to_ioend(inode, bh, offset,
842 set_buffer_dirty(bh);
844 mark_buffer_dirty(bh);
850 if (buffer_mapped(bh) && all_bh && startio) {
852 xfs_add_to_ioend(inode, bh, offset,
860 } while (offset += len, (bh = bh->b_this_page) != head);
862 if (uptodate && bh == head)
863 SetPageUptodate(page);
868 if (wbc->nr_to_write <= 0)
871 xfs_start_page_writeback(page, !page_dirty, count);
882 * Convert & write out a cluster of pages in the same extent as defined
883 * by mp and following the start page.
890 xfs_ioend_t **ioendp,
891 struct writeback_control *wbc,
899 pagevec_init(&pvec, 0);
900 while (!done && tindex <= tlast) {
901 unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
903 if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
906 for (i = 0; i < pagevec_count(&pvec); i++) {
907 done = xfs_convert_page(inode, pvec.pages[i], tindex++,
908 iomapp, ioendp, wbc, startio, all_bh);
913 pagevec_release(&pvec);
919 * Calling this without startio set means we are being asked to make a dirty
920 * page ready for freeing it's buffers. When called with startio set then
921 * we are coming from writepage.
923 * When called with startio set it is important that we write the WHOLE
925 * The bh->b_state's cannot know if any of the blocks or which block for
926 * that matter are dirty due to mmap writes, and therefore bh uptodate is
927 * only valid if the page itself isn't completely uptodate. Some layers
928 * may clear the page dirty flag prior to calling write page, under the
929 * assumption the entire page will be written out; by not writing out the
930 * whole page the page can be reused before all valid dirty data is
931 * written out. Note: in the case of a page that has been dirty'd by
932 * mapwrite and but partially setup by block_prepare_write the
933 * bh->b_states's will not agree and only ones setup by BPW/BCW will have
934 * valid state, thus the whole page must be written out thing.
938 xfs_page_state_convert(
941 struct writeback_control *wbc,
943 int unmapped) /* also implies page uptodate */
945 struct buffer_head *bh, *head;
947 xfs_ioend_t *ioend = NULL, *iohead = NULL;
949 unsigned long p_offset = 0;
951 __uint64_t end_offset;
952 pgoff_t end_index, last_index, tlast;
954 int flags, err, iomap_valid = 0, uptodate = 1;
955 int page_dirty, count = 0;
957 int all_bh = unmapped;
960 if (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking)
961 trylock |= BMAPI_TRYLOCK;
964 /* Is this page beyond the end of the file? */
965 offset = i_size_read(inode);
966 end_index = offset >> PAGE_CACHE_SHIFT;
967 last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
968 if (page->index >= end_index) {
969 if ((page->index >= end_index + 1) ||
970 !(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
978 * page_dirty is initially a count of buffers on the page before
979 * EOF and is decremented as we move each into a cleanable state.
983 * End offset is the highest offset that this page should represent.
984 * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
985 * will evaluate non-zero and be less than PAGE_CACHE_SIZE and
986 * hence give us the correct page_dirty count. On any other page,
987 * it will be zero and in that case we need page_dirty to be the
988 * count of buffers on the page.
990 end_offset = min_t(unsigned long long,
991 (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT, offset);
992 len = 1 << inode->i_blkbits;
993 p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
995 p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
996 page_dirty = p_offset / len;
998 bh = head = page_buffers(page);
999 offset = page_offset(page);
1003 /* TODO: cleanup count and page_dirty */
1006 if (offset >= end_offset)
1008 if (!buffer_uptodate(bh))
1010 if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio) {
1012 * the iomap is actually still valid, but the ioend
1013 * isn't. shouldn't happen too often.
1020 iomap_valid = xfs_iomap_valid(&iomap, offset);
1023 * First case, map an unwritten extent and prepare for
1024 * extent state conversion transaction on completion.
1026 * Second case, allocate space for a delalloc buffer.
1027 * We can return EAGAIN here in the release page case.
1029 * Third case, an unmapped buffer was found, and we are
1030 * in a path where we need to write the whole page out.
1032 if (buffer_unwritten(bh) || buffer_delay(bh) ||
1033 ((buffer_uptodate(bh) || PageUptodate(page)) &&
1034 !buffer_mapped(bh) && (unmapped || startio))) {
1038 * Make sure we don't use a read-only iomap
1040 if (flags == BMAPI_READ)
1043 if (buffer_unwritten(bh)) {
1044 type = IOMAP_UNWRITTEN;
1045 flags = BMAPI_WRITE | BMAPI_IGNSTATE;
1046 } else if (buffer_delay(bh)) {
1048 flags = BMAPI_ALLOCATE | trylock;
1051 flags = BMAPI_WRITE | BMAPI_MMAP;
1056 * if we didn't have a valid mapping then we
1057 * need to ensure that we put the new mapping
1058 * in a new ioend structure. This needs to be
1059 * done to ensure that the ioends correctly
1060 * reflect the block mappings at io completion
1061 * for unwritten extent conversion.
1064 if (type == IOMAP_NEW) {
1065 size = xfs_probe_cluster(inode,
1071 err = xfs_map_blocks(inode, offset, size,
1075 iomap_valid = xfs_iomap_valid(&iomap, offset);
1078 xfs_map_at_offset(bh, offset,
1079 inode->i_blkbits, &iomap);
1081 xfs_add_to_ioend(inode, bh, offset,
1085 set_buffer_dirty(bh);
1087 mark_buffer_dirty(bh);
1092 } else if (buffer_uptodate(bh) && startio) {
1094 * we got here because the buffer is already mapped.
1095 * That means it must already have extents allocated
1096 * underneath it. Map the extent by reading it.
1098 if (!iomap_valid || flags != BMAPI_READ) {
1100 size = xfs_probe_cluster(inode, page, bh,
1102 err = xfs_map_blocks(inode, offset, size,
1106 iomap_valid = xfs_iomap_valid(&iomap, offset);
1110 * We set the type to IOMAP_NEW in case we are doing a
1111 * small write at EOF that is extending the file but
1112 * without needing an allocation. We need to update the
1113 * file size on I/O completion in this case so it is
1114 * the same case as having just allocated a new extent
1115 * that we are writing into for the first time.
1118 if (trylock_buffer(bh)) {
1119 ASSERT(buffer_mapped(bh));
1122 xfs_add_to_ioend(inode, bh, offset, type,
1123 &ioend, !iomap_valid);
1129 } else if ((buffer_uptodate(bh) || PageUptodate(page)) &&
1130 (unmapped || startio)) {
1137 } while (offset += len, ((bh = bh->b_this_page) != head));
1139 if (uptodate && bh == head)
1140 SetPageUptodate(page);
1143 xfs_start_page_writeback(page, 1, count);
1145 if (ioend && iomap_valid) {
1146 offset = (iomap.iomap_offset + iomap.iomap_bsize - 1) >>
1148 tlast = min_t(pgoff_t, offset, last_index);
1149 xfs_cluster_write(inode, page->index + 1, &iomap, &ioend,
1150 wbc, startio, all_bh, tlast);
1154 xfs_submit_ioend(wbc, iohead);
1160 xfs_cancel_ioend(iohead);
1163 * If it's delalloc and we have nowhere to put it,
1164 * throw it away, unless the lower layers told
1167 if (err != -EAGAIN) {
1169 block_invalidatepage(page, 0);
1170 ClearPageUptodate(page);
1176 * writepage: Called from one of two places:
1178 * 1. we are flushing a delalloc buffer head.
1180 * 2. we are writing out a dirty page. Typically the page dirty
1181 * state is cleared before we get here. In this case is it
1182 * conceivable we have no buffer heads.
1184 * For delalloc space on the page we need to allocate space and
1185 * flush it. For unmapped buffer heads on the page we should
1186 * allocate space if the page is uptodate. For any other dirty
1187 * buffer heads on the page we should flush them.
1189 * If we detect that a transaction would be required to flush
1190 * the page, we have to check the process flags first, if we
1191 * are already in a transaction or disk I/O during allocations
1192 * is off, we need to fail the writepage and redirty the page.
1198 struct writeback_control *wbc)
1202 int delalloc, unmapped, unwritten;
1203 struct inode *inode = page->mapping->host;
1205 xfs_page_trace(XFS_WRITEPAGE_ENTER, inode, page, 0);
1208 * We need a transaction if:
1209 * 1. There are delalloc buffers on the page
1210 * 2. The page is uptodate and we have unmapped buffers
1211 * 3. The page is uptodate and we have no buffers
1212 * 4. There are unwritten buffers on the page
1215 if (!page_has_buffers(page)) {
1219 xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
1220 if (!PageUptodate(page))
1222 need_trans = delalloc + unmapped + unwritten;
1226 * If we need a transaction and the process flags say
1227 * we are already in a transaction, or no IO is allowed
1228 * then mark the page dirty again and leave the page
1231 if (current_test_flags(PF_FSTRANS) && need_trans)
1235 * Delay hooking up buffer heads until we have
1236 * made our go/no-go decision.
1238 if (!page_has_buffers(page))
1239 create_empty_buffers(page, 1 << inode->i_blkbits, 0);
1243 * VM calculation for nr_to_write seems off. Bump it way
1244 * up, this gets simple streaming writes zippy again.
1245 * To be reviewed again after Jens' writeback changes.
1247 wbc->nr_to_write *= 4;
1250 * Convert delayed allocate, unwritten or unmapped space
1251 * to real space and flush out to disk.
1253 error = xfs_page_state_convert(inode, page, wbc, 1, unmapped);
1254 if (error == -EAGAIN)
1256 if (unlikely(error < 0))
1262 redirty_page_for_writepage(wbc, page);
1272 struct address_space *mapping,
1273 struct writeback_control *wbc)
1275 xfs_iflags_clear(XFS_I(mapping->host), XFS_ITRUNCATED);
1276 return generic_writepages(mapping, wbc);
1280 * Called to move a page into cleanable state - and from there
1281 * to be released. Possibly the page is already clean. We always
1282 * have buffer heads in this call.
1284 * Returns 0 if the page is ok to release, 1 otherwise.
1286 * Possible scenarios are:
1288 * 1. We are being called to release a page which has been written
1289 * to via regular I/O. buffer heads will be dirty and possibly
1290 * delalloc. If no delalloc buffer heads in this case then we
1291 * can just return zero.
1293 * 2. We are called to release a page which has been written via
1294 * mmap, all we need to do is ensure there is no delalloc
1295 * state in the buffer heads, if not we can let the caller
1296 * free them and we should come back later via writepage.
1303 struct inode *inode = page->mapping->host;
1304 int dirty, delalloc, unmapped, unwritten;
1305 struct writeback_control wbc = {
1306 .sync_mode = WB_SYNC_ALL,
1310 xfs_page_trace(XFS_RELEASEPAGE_ENTER, inode, page, 0);
1312 if (!page_has_buffers(page))
1315 xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
1316 if (!delalloc && !unwritten)
1319 if (!(gfp_mask & __GFP_FS))
1322 /* If we are already inside a transaction or the thread cannot
1323 * do I/O, we cannot release this page.
1325 if (current_test_flags(PF_FSTRANS))
1329 * Convert delalloc space to real space, do not flush the
1330 * data out to disk, that will be done by the caller.
1331 * Never need to allocate space here - we will always
1332 * come back to writepage in that case.
1334 dirty = xfs_page_state_convert(inode, page, &wbc, 0, 0);
1335 if (dirty == 0 && !unwritten)
1340 return try_to_free_buffers(page);
1345 struct inode *inode,
1347 struct buffer_head *bh_result,
1350 bmapi_flags_t flags)
1358 offset = (xfs_off_t)iblock << inode->i_blkbits;
1359 ASSERT(bh_result->b_size >= (1 << inode->i_blkbits));
1360 size = bh_result->b_size;
1362 if (!create && direct && offset >= i_size_read(inode))
1365 error = xfs_iomap(XFS_I(inode), offset, size,
1366 create ? flags : BMAPI_READ, &iomap, &niomap);
1372 if (iomap.iomap_bn != IOMAP_DADDR_NULL) {
1374 * For unwritten extents do not report a disk address on
1375 * the read case (treat as if we're reading into a hole).
1377 if (create || !(iomap.iomap_flags & IOMAP_UNWRITTEN)) {
1378 xfs_map_buffer(bh_result, &iomap, offset,
1381 if (create && (iomap.iomap_flags & IOMAP_UNWRITTEN)) {
1383 bh_result->b_private = inode;
1384 set_buffer_unwritten(bh_result);
1389 * If this is a realtime file, data may be on a different device.
1390 * to that pointed to from the buffer_head b_bdev currently.
1392 bh_result->b_bdev = iomap.iomap_target->bt_bdev;
1395 * If we previously allocated a block out beyond eof and we are now
1396 * coming back to use it then we will need to flag it as new even if it
1397 * has a disk address.
1399 * With sub-block writes into unwritten extents we also need to mark
1400 * the buffer as new so that the unwritten parts of the buffer gets
1404 ((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) ||
1405 (offset >= i_size_read(inode)) ||
1406 (iomap.iomap_flags & (IOMAP_NEW|IOMAP_UNWRITTEN))))
1407 set_buffer_new(bh_result);
1409 if (iomap.iomap_flags & IOMAP_DELAY) {
1412 set_buffer_uptodate(bh_result);
1413 set_buffer_mapped(bh_result);
1414 set_buffer_delay(bh_result);
1418 if (direct || size > (1 << inode->i_blkbits)) {
1419 ASSERT(iomap.iomap_bsize - iomap.iomap_delta > 0);
1420 offset = min_t(xfs_off_t,
1421 iomap.iomap_bsize - iomap.iomap_delta, size);
1422 bh_result->b_size = (ssize_t)min_t(xfs_off_t, LONG_MAX, offset);
1430 struct inode *inode,
1432 struct buffer_head *bh_result,
1435 return __xfs_get_blocks(inode, iblock,
1436 bh_result, create, 0, BMAPI_WRITE);
1440 xfs_get_blocks_direct(
1441 struct inode *inode,
1443 struct buffer_head *bh_result,
1446 return __xfs_get_blocks(inode, iblock,
1447 bh_result, create, 1, BMAPI_WRITE|BMAPI_DIRECT);
1457 xfs_ioend_t *ioend = iocb->private;
1460 * Non-NULL private data means we need to issue a transaction to
1461 * convert a range from unwritten to written extents. This needs
1462 * to happen from process context but aio+dio I/O completion
1463 * happens from irq context so we need to defer it to a workqueue.
1464 * This is not necessary for synchronous direct I/O, but we do
1465 * it anyway to keep the code uniform and simpler.
1467 * Well, if only it were that simple. Because synchronous direct I/O
1468 * requires extent conversion to occur *before* we return to userspace,
1469 * we have to wait for extent conversion to complete. Look at the
1470 * iocb that has been passed to us to determine if this is AIO or
1471 * not. If it is synchronous, tell xfs_finish_ioend() to kick the
1472 * workqueue and wait for it to complete.
1474 * The core direct I/O code might be changed to always call the
1475 * completion handler in the future, in which case all this can
1478 ioend->io_offset = offset;
1479 ioend->io_size = size;
1480 if (ioend->io_type == IOMAP_READ) {
1481 xfs_finish_ioend(ioend, 0);
1482 } else if (private && size > 0) {
1483 xfs_finish_ioend(ioend, is_sync_kiocb(iocb));
1486 * A direct I/O write ioend starts it's life in unwritten
1487 * state in case they map an unwritten extent. This write
1488 * didn't map an unwritten extent so switch it's completion
1491 ioend->io_type = IOMAP_NEW;
1492 xfs_finish_ioend(ioend, 0);
1496 * blockdev_direct_IO can return an error even after the I/O
1497 * completion handler was called. Thus we need to protect
1498 * against double-freeing.
1500 iocb->private = NULL;
1507 const struct iovec *iov,
1509 unsigned long nr_segs)
1511 struct file *file = iocb->ki_filp;
1512 struct inode *inode = file->f_mapping->host;
1513 struct block_device *bdev;
1516 bdev = xfs_find_bdev_for_inode(XFS_I(inode));
1519 iocb->private = xfs_alloc_ioend(inode, IOMAP_UNWRITTEN);
1520 ret = blockdev_direct_IO_own_locking(rw, iocb, inode,
1521 bdev, iov, offset, nr_segs,
1522 xfs_get_blocks_direct,
1525 iocb->private = xfs_alloc_ioend(inode, IOMAP_READ);
1526 ret = blockdev_direct_IO_no_locking(rw, iocb, inode,
1527 bdev, iov, offset, nr_segs,
1528 xfs_get_blocks_direct,
1532 if (unlikely(ret != -EIOCBQUEUED && iocb->private))
1533 xfs_destroy_ioend(iocb->private);
1540 struct address_space *mapping,
1544 struct page **pagep,
1548 return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
1554 struct address_space *mapping,
1557 struct inode *inode = (struct inode *)mapping->host;
1558 struct xfs_inode *ip = XFS_I(inode);
1560 xfs_itrace_entry(XFS_I(inode));
1561 xfs_ilock(ip, XFS_IOLOCK_SHARED);
1562 xfs_flush_pages(ip, (xfs_off_t)0, -1, 0, FI_REMAPF);
1563 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
1564 return generic_block_bmap(mapping, block, xfs_get_blocks);
1569 struct file *unused,
1572 return mpage_readpage(page, xfs_get_blocks);
1577 struct file *unused,
1578 struct address_space *mapping,
1579 struct list_head *pages,
1582 return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
1586 xfs_vm_invalidatepage(
1588 unsigned long offset)
1590 xfs_page_trace(XFS_INVALIDPAGE_ENTER,
1591 page->mapping->host, page, offset);
1592 block_invalidatepage(page, offset);
1595 const struct address_space_operations xfs_address_space_operations = {
1596 .readpage = xfs_vm_readpage,
1597 .readpages = xfs_vm_readpages,
1598 .writepage = xfs_vm_writepage,
1599 .writepages = xfs_vm_writepages,
1600 .sync_page = block_sync_page,
1601 .releasepage = xfs_vm_releasepage,
1602 .invalidatepage = xfs_vm_invalidatepage,
1603 .write_begin = xfs_vm_write_begin,
1604 .write_end = generic_write_end,
1605 .bmap = xfs_vm_bmap,
1606 .direct_IO = xfs_vm_direct_IO,
1607 .migratepage = buffer_migrate_page,
1608 .is_partially_uptodate = block_is_partially_uptodate,
1609 .error_remove_page = generic_error_remove_page,