• Ryusuke Konishi's avatar
    nilfs2: get rid of nilfs_sb_info structure · e3154e97
    Ryusuke Konishi authored
    This directly uses sb->s_fs_info to keep a nilfs filesystem object and
    fully removes the intermediate nilfs_sb_info structure.  With this
    change, the hierarchy of on-memory structures of nilfs will be
    simplified as follows:
    
    Before:
      super_block
           -> nilfs_sb_info
                 -> the_nilfs
                       -> cptree --+-> nilfs_root (current file system)
                                   +-> nilfs_root (snapshot A)
                                   +-> nilfs_root (snapshot B)
                                   :
                 -> nilfs_sc_info (log writer structure)
    After:
      super_block
           -> the_nilfs
                 -> cptree --+-> nilfs_root (current file system)
                             +-> nilfs_root (snapshot A)
                             +-> nilfs_root (snapshot B)
                             :
                 -> nilfs_sc_info (log writer structure)
    
    The reason why we didn't design so from the beginning is because the
    initial shape also differed from the above.  The early hierachy was
    composed of "per-mount-point" super_block -> nilfs_sb_info pairs and a
    shared nilfs object.  On the kernel 2.6.37, it was changed to the
    current shape in order to unify super block instances into one per
    device, and this cleanup became applicable as the result.
    Signed-off-by: default avatarRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
    e3154e97
bmap.c 14.4 KB