* 10 Mar 2003 Andrey Borzenkov <arvidjaar@mail.ru> 1.1.1

  - fix stupid bug in subfs inode refcounting. It was visible with
    hardlinks only so CD-ROM users would not ever see it.

* 8 Mar 2003 Andrey Borzenkov <arvidjaar@mail.ru> 1.1.0

  - files cannot use inode obsolete flag - it does not work for
    root inodes

  - make file system structure exact mirror of subfs - now there
    is 1-to-1 correspondence between super- and subfs files, dentries
    and inodes. This is needed to properly manage write access without
    too much locking

  - finally realized that subfs cannot be obsolete; use either file
    or inode pointer in all calls into subfs.c to check for freshness

  - debug is now per-mount; added trace of all functions
  
  - move setting of SUPERMOUNT_DEBUG to Makefile instead of supermount_i.h

* 1 Mar 2003 Andrey Borzenkov <arvidjaar@mail.ru> 1.0.0

  - make sure it is always possible umount subfs. It does it by
    keeping list of opened files (in addition to inodes) and closing
    them if media change is detected.

  - make sure subfs can't go away while it is being in use. For
    files it get_file for subfile to ensure subfs mnt is not freed. For
    inode operation it increments usage counter of submnt for duration
    of operation.

  - make sure supermounted device can't be mounted twice (that is
    allowed by kernel) because it relies on being the only "owner" of
    subfs. It does it by checking for MS_SUPERMOUNTED flag on mount.

  - make sure you can't mount over supermounted directory. Allowing
    it is a nightmare and I cannot see any reason for it (if you can
    provide valid one - I may reconsider this part). It does so by
    adding fstype flag and checking it on mounting.

  - reject mount -o remount for the time being (until we can deal
    with it properly)

  - completely change implementation of individual inode methods.
    Instead of calling VFS recursively it calls subfs methods directly.
    It is to ensure we are in full control of subfs (assuming it behaves
    properly :)

  - properly implement VM methods. Currently changing media would
    leave you with vm_area pointing to no more existing inode ...

  - remove many obsolete pieces like flags that just duplicate
    existing information.

  - ensure coherency between super- and subfs dentries. Either we
    have both active in dcache or do not have them at all.

  - fixe the problem with media ejection after direct access to CD-ROM

  - add "just disc change" to all operations to detect media change
    as soon as possible. It is possible to add option to do it just
    for writable media or to completely turn it off.
