• Theodore Ts'o's avatar
    ext4: move ext4_update_i_disksize() into mpage_map_and_submit_extent() · 622cad13
    Theodore Ts'o authored
    The function ext4_update_i_disksize() is used in only one place, in
    the function mpage_map_and_submit_extent().  Move its code to simplify
    the code paths, and also move the call to ext4_mark_inode_dirty() into
    the i_data_sem's critical region, to be consistent with all of the
    other places where we update i_disksize.  That way, we also keep the
    raw_inode's i_disksize protected, to avoid the following race:
    
          CPU #1                                 CPU #2
    
       down_write(&i_data_sem)
       Modify i_disk_size
       up_write(&i_data_sem)
                                            down_write(&i_data_sem)
                                            Modify i_disk_size
                                            Copy i_disk_size to on-disk inode
                                            up_write(&i_data_sem)
       Copy i_disk_size to on-disk inode
    Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
    Reviewed-by: default avatarJan Kara <jack@suse.cz>
    Cc: stable@vger.kernel.org
    622cad13
ext4.h 101 KB