Commit 81a0d3e1 authored by Matthew Wilcox's avatar Matthew Wilcox Committed by Theodore Ts'o
Browse files

ext4: Convert mpage_submit_page() to mpage_submit_folio() 



All callers now have a folio so we can pass one in and use the folio
APIs to support large folios as well as save instructions by eliminating
calls to compound_head().

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarTheodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20230324180129.1220691-7-willy@infradead.org


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 4da2f6e3

fs/ext4/inode.c

+15 −16
Original line number Diff line number Diff line
@@ -1869,34 +1869,33 @@ static void mpage_page_done(struct mpage_da_data *mpd, struct page *page) 
	unlock_page(page);

}



static int mpage_submit_page(struct mpage_da_data *mpd, struct page *page)

static int mpage_submit_folio(struct mpage_da_data *mpd, struct folio *folio)

{

	int len;

	size_t len;

	loff_t size;

	int err;



	BUG_ON(page->index != mpd->first_page);

	clear_page_dirty_for_io(page);

	BUG_ON(folio->index != mpd->first_page);

	folio_clear_dirty_for_io(folio);

	/*

	 * We have to be very careful here!  Nothing protects writeback path

	 * against i_size changes and the page can be writeably mapped into

	 * page tables. So an application can be growing i_size and writing

	 * data through mmap while writeback runs. clear_page_dirty_for_io()

	 * data through mmap while writeback runs. folio_clear_dirty_for_io()

	 * write-protects our page in page tables and the page cannot get

	 * written to again until we release page lock. So only after

	 * clear_page_dirty_for_io() we are safe to sample i_size for

	 * written to again until we release folio lock. So only after

	 * folio_clear_dirty_for_io() we are safe to sample i_size for

	 * ext4_bio_write_page() to zero-out tail of the written page. We rely

	 * on the barrier provided by TestClearPageDirty in

	 * clear_page_dirty_for_io() to make sure i_size is really sampled only

	 * folio_clear_dirty_for_io() to make sure i_size is really sampled only

	 * after page tables are updated.

	 */

	size = i_size_read(mpd->inode);

	if (page->index == size >> PAGE_SHIFT &&

	len = folio_size(folio);

	if (folio_pos(folio) + len > size &&

	    !ext4_verity_in_progress(mpd->inode))

		len = size & ~PAGE_MASK;

	else

		len = PAGE_SIZE;

	err = ext4_bio_write_page(&mpd->io_submit, page, len);

	err = ext4_bio_write_page(&mpd->io_submit, &folio->page, len);

	if (!err)

		mpd->wbc->nr_to_write--;
@@ -2009,7 +2008,7 @@ static int mpage_process_page_bufs(struct mpage_da_data *mpd, 
	} while (lblk++, (bh = bh->b_this_page) != head);

	/* So far everything mapped? Submit the page for IO. */

	if (mpd->map.m_len == 0) {

		err = mpage_submit_page(mpd, head->b_page);

		err = mpage_submit_folio(mpd, head->b_folio);

		if (err < 0)

			return err;

		mpage_page_done(mpd, head->b_page);
@@ -2142,7 +2141,7 @@ static int mpage_map_and_submit_buffers(struct mpage_da_data *mpd) 
			if (err < 0 || map_bh)

				goto out;

			/* Page fully mapped - let IO run! */

			err = mpage_submit_page(mpd, &folio->page);

			err = mpage_submit_folio(mpd, folio);

			if (err < 0)

				goto out;

			mpage_page_done(mpd, &folio->page);
@@ -2532,12 +2531,12 @@ static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd) 
				if (ext4_page_nomap_can_writeout(&folio->page)) {

					WARN_ON_ONCE(sb->s_writers.frozen ==

						     SB_FREEZE_COMPLETE);

					err = mpage_submit_page(mpd, &folio->page);

					err = mpage_submit_folio(mpd, folio);

					if (err < 0)

						goto out;

				}

				/* Pending dirtying of journalled data? */

				if (PageChecked(&folio->page)) {

				if (folio_test_checked(folio)) {

					WARN_ON_ONCE(sb->s_writers.frozen >=

						     SB_FREEZE_FS);

					err = mpage_journal_page_buffers(handle,