ext4: handle redirtying in ext4_bio_write_page()

Since we want to transition transaction commits to use ext4_writepages()
for writing back ordered, add handling of page redirtying into
ext4_bio_write_page(). Also move buffer dirty bit clearing into the same
place other buffer state handling.

Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221207112722.22220-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 97fa7b4c645fdd0c9bab5be3d6e0a82c9bf3054b..4e68ace86f11dc6ed39d4f244ba785e3cc8ca7e3 100644 (file)
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -482,6 +482,13 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
                        /* A hole? We can safely clear the dirty bit */
                        if (!buffer_mapped(bh))
                                clear_buffer_dirty(bh);
+                       /*
+                        * Keeping dirty some buffer we cannot write? Make
+                        * sure to redirty the page. This happens e.g. when
+                        * doing writeout for transaction commit.
+                        */
+                       if (buffer_dirty(bh) && !PageDirty(page))
+                               redirty_page_for_writepage(wbc, page);
                        if (io->io_bio)
                                ext4_io_submit(io);
                        continue;
@@ -489,6 +496,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
                if (buffer_new(bh))
                        clear_buffer_new(bh);
                set_buffer_async_write(bh);
+               clear_buffer_dirty(bh);
                nr_to_submit++;
        } while ((bh = bh->b_this_page) != head);
 
@@ -532,7 +540,10 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
                        printk_ratelimited(KERN_ERR "%s: ret = %d\n", __func__, ret);
                        redirty_page_for_writepage(wbc, page);
                        do {
-                               clear_buffer_async_write(bh);
+                               if (buffer_async_write(bh)) {
+                                       clear_buffer_async_write(bh);
+                                       set_buffer_dirty(bh);
+                               }
                                bh = bh->b_this_page;
                        } while (bh != head);
                        goto unlock;
@@ -546,7 +557,6 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
                io_submit_add_bh(io, inode,
                                 bounce_page ? bounce_page : page, bh);
                nr_submitted++;
-               clear_buffer_dirty(bh);
        } while ((bh = bh->b_this_page) != head);
 
 unlock: