Commit 46672a44 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by David Sterba
Browse files

btrfs: merge write_one_subpage_eb into write_one_eb 



Most of the code in write_one_subpage_eb and write_one_eb is shared,
so merge the two functions into one.

Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent d7172f52

fs/btrfs/extent_io.c

+25 −55
Original line number Diff line number Diff line
@@ -1808,68 +1808,37 @@ static void prepare_eb_write(struct extent_buffer *eb) 
	}

}



/*

 * Unlike the work in write_one_eb(), we rely completely on extent locking.

 * Page locking is only utilized at minimum to keep the VMM code happy.

 */

static void write_one_subpage_eb(struct extent_buffer *eb,

static noinline_for_stack void write_one_eb(struct extent_buffer *eb,

					    struct writeback_control *wbc)

{

	struct btrfs_fs_info *fs_info = eb->fs_info;

	struct page *page = eb->pages[0];

	bool no_dirty_ebs = false;

	struct btrfs_bio *bbio;



	prepare_eb_write(eb);



	/* clear_page_dirty_for_io() in subpage helper needs page locked */

	lock_page(page);

	btrfs_subpage_set_writeback(fs_info, page, eb->start, eb->len);



	/* Check if this is the last dirty bit to update nr_written */

	no_dirty_ebs = btrfs_subpage_clear_and_test_dirty(fs_info, page,

							  eb->start, eb->len);

	if (no_dirty_ebs)

		clear_page_dirty_for_io(page);



	bbio = btrfs_bio_alloc(INLINE_EXTENT_BUFFER_PAGES,

			       REQ_OP_WRITE | REQ_META | wbc_to_write_flags(wbc),

			       eb->fs_info, extent_buffer_write_end_io, eb);

	bbio->bio.bi_iter.bi_sector = eb->start >> SECTOR_SHIFT;

	bio_set_dev(&bbio->bio, fs_info->fs_devices->latest_dev->bdev);

	wbc_init_bio(wbc, &bbio->bio);

	bbio->inode = BTRFS_I(eb->fs_info->btree_inode);

	bbio->file_offset = eb->start;

	__bio_add_page(&bbio->bio, page, eb->len, eb->start - page_offset(page));

	wbc_account_cgroup_owner(wbc, page, eb->len);

	unlock_page(page);

	btrfs_submit_bio(bbio, 0);

	if (fs_info->nodesize < PAGE_SIZE) {

		struct page *p = eb->pages[0];



	/*

	 * Submission finished without problem, if no range of the page is

	 * dirty anymore, we have submitted a page.  Update nr_written in wbc.

	 */

	if (no_dirty_ebs)

		lock_page(p);

		btrfs_subpage_set_writeback(fs_info, p, eb->start, eb->len);

		if (btrfs_subpage_clear_and_test_dirty(fs_info, p, eb->start,

						       eb->len)) {

			clear_page_dirty_for_io(p);

			wbc->nr_to_write--;

		}



static noinline_for_stack void write_one_eb(struct extent_buffer *eb,

					    struct writeback_control *wbc)

{

	struct btrfs_bio *bbio;

	int i, num_pages;



	prepare_eb_write(eb);



	bbio = btrfs_bio_alloc(INLINE_EXTENT_BUFFER_PAGES,

			       REQ_OP_WRITE | REQ_META | wbc_to_write_flags(wbc),

			       eb->fs_info, extent_buffer_write_end_io, eb);

	bbio->bio.bi_iter.bi_sector = eb->start >> SECTOR_SHIFT;

	bio_set_dev(&bbio->bio, eb->fs_info->fs_devices->latest_dev->bdev);

	wbc_init_bio(wbc, &bbio->bio);

	bbio->inode = BTRFS_I(eb->fs_info->btree_inode);

	bbio->file_offset = eb->start;



	num_pages = num_extent_pages(eb);

	for (i = 0; i < num_pages; i++) {

		__bio_add_page(&bbio->bio, p, eb->len, eb->start - page_offset(p));

		wbc_account_cgroup_owner(wbc, p, eb->len);

		unlock_page(p);

	} else {

		for (int i = 0; i < num_extent_pages(eb); i++) {

			struct page *p = eb->pages[i];



			lock_page(p);
@@ -1880,6 +1849,7 @@ static noinline_for_stack void write_one_eb(struct extent_buffer *eb, 
			wbc->nr_to_write--;

			unlock_page(p);

		}

	}

	btrfs_submit_bio(bbio, 0);

}
@@ -1950,7 +1920,7 @@ static int submit_eb_subpage(struct page *page, struct writeback_control *wbc) 
			continue;



		if (lock_extent_buffer_for_io(eb, wbc)) {

			write_one_subpage_eb(eb, wbc);

			write_one_eb(eb, wbc);

			submitted++;

		}

		free_extent_buffer(eb);