• Amir Goldstein's avatar
    ovl: store file handle of lower inode on copy up · 3a1e819b
    Amir Goldstein authored
    Sometimes it is interesting to know if an upper file is pure upper or a
    copy up target, and if it is a copy up target, it may be interesting to
    find the copy up origin.
    This will be used to preserve lower inode numbers across copy up.
    Store the lower inode file handle in upper inode extended attribute
    overlay.origin on copy up to use it later for these cases.  Store the lower
    filesystem uuid along side the file handle, so we can validate that we are
    looking for the origin file in the original fs.
    If lower fs does not support NFS export ops store a zero sized xattr so we
    can always use the overlay.origin xattr to distinguish between a copy up
    and a pure upper inode.
    Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
    Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
copy_up.c 12.5 KB