lkml.org 
[lkml]   [1999]   [Apr]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    Subject2.2.5:fs/super.c comment indicates stacked mounts possible?
    in fs/super.c do_mount():
    * [21-Mar-97] T.Schoebel-Theuer: Now this can be overridden when
    * supplying a leading "!" before the dir_name, allowing "stacks" of
    * mounted filesystems. The stacking will only influence any pathname
    lookups
    * _after_ the mount, but open file descriptors or working directories
    that
    * are now covered remain valid. For example, when you overmount /home,
    any
    * process with old cwd /home/joe will continue to use the old
    versions,
    * as long as relative paths are used, but absolute paths like
    /home/joe/xxx
    * will go to the new "top of stack" version. In general, crossing a
    * mount point will always go to the top of stack element.
    * Anyone using this new feature must know what he/she is doing.

    This seems to indicate I can mount several filesystems under one mount
    point? (I didn't find any further comments/code for this)

    I'm asking because I'm thinking about an overlay mount function, which
    means you can mount a filesystem on top of another one on the same
    mount point. Purpose: for example, I could overlay my minimal /usr
    installation with a big nfs-mounted /usr filesystem, and all the files
    that don't exist locally on the disk are taken (transparently) from the
    nfs filesystem. The question above has not much to do with this except
    that I'm curious now that I discovered that comment, but maybe some
    people who're familiar with the fs-implementation could comment on the idea.
    ===
    --
    Michael Hasenstein
    http://www.csn.tu-chemnitz.de/~mha/
    Private Pilot (ASEL) since 1998
    _________________________________________________________
    Do You Yahoo!?
    Get your free @yahoo.com address at http://mail.yahoo.com


    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.rutgers.edu
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-03-22 13:51    [W:0.130 / U:62.172 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site