ext4: Drop special handling of journalled data from ext4_sync_file()

Now that ext4_writepages() make sure all pages with journalled data are
stable on disk, we don't need special handling of journalled data in
ext4_sync_file().

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230329154950.19720-6-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/fsync.c

@@ -153,23 +153,12 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 		goto out;
 
 	/*
-	 * data=writeback,ordered:
 	 *  The caller's filemap_fdatawrite()/wait will sync the data.
 	 *  Metadata is in the journal, we wait for proper transaction to
 	 *  commit here.
-	 *
-	 * data=journal:
-	 *  filemap_fdatawrite won't do anything (the buffers are clean).
-	 *  ext4_force_commit will write the file data into the journal and
-	 *  will wait on that.
-	 *  filemap_fdatawait() will encounter a ton of newly-dirtied pages
-	 *  (they were dirtied by commit).  But that's OK - the blocks are
-	 *  safe in-journal, which is all fsync() needs to ensure.
 	 */
 	if (!sbi->s_journal)
 		ret = ext4_fsync_nojournal(inode, datasync, &needs_barrier);
-	else if (ext4_should_journal_data(inode))
-		ret = ext4_force_commit(inode->i_sb);
 	else
 		ret = ext4_fsync_journal(inode, datasync, &needs_barrier);