With journalled data it can happen that checkpointing code will write
out page contents without clearing the page dirty bit. The logic in
ext4_page_nomap_can_writeout() then results in us never calling
mpage_submit_page() and thus clearing the dirty bit. Drop the
optimization with ext4_page_nomap_can_writeout() and just always call to
mpage_submit_page(). ext4_bio_write_page() knows when to redirty the
page and the additional clearing & setting of page dirty bit for ordered
mode writeout is not that expensive to jump through the hoops for it.
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
fs/ext4/inode.c | 25 +++++--------------------
1 file changed, 5 insertions(+), 20 deletions(-)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 78e29da70af7..85299c90b0f7 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2342,19 +2342,6 @@ static int ext4_da_writepages_trans_blocks(struct inode *inode)
MAX_WRITEPAGES_EXTENT_LEN + bpp - 1, bpp);
}
-/* Return true if the page needs to be written as part of transaction commit */
-static bool ext4_page_nomap_can_writeout(struct page *page)
-{
- struct buffer_head *bh, *head;
-
- bh = head = page_buffers(page);
- do {
- if (buffer_dirty(bh) && buffer_mapped(bh) && !buffer_delay(bh))
- return true;
- } while ((bh = bh->b_this_page) != head);
- return false;
-}
-
static int ext4_journal_page_buffers(handle_t *handle, struct page *page,
int len)
{
@@ -2539,13 +2526,11 @@ static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd)
* range operations before discarding the page cache.
*/
if (!mpd->can_map) {
- 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);
- if (err < 0)
- goto out;
- }
+ WARN_ON_ONCE(sb->s_writers.frozen ==
+ SB_FREEZE_COMPLETE);
+ err = mpage_submit_page(mpd, &folio->page);
+ if (err < 0)
+ goto out;
/* Pending dirtying of journalled data? */
if (PageChecked(&folio->page)) {
WARN_ON_ONCE(sb->s_writers.frozen >=
--
2.35.3
