• Al Viro's avatar
    take the targets of /proc/*/ns/* symlinks to separate fs · e149ed2b
    Al Viro authored
    New pseudo-filesystem: nsfs.  Targets of /proc/*/ns/* live there now.
    It's not mountable (not even registered, so it's not in /proc/filesystems,
    etc.).  Files on it *are* bindable - we explicitly permit that in do_loopback().
    
    This stuff lives in fs/nsfs.c now; proc_ns_fget() moved there as well.
    get_proc_ns() is a macro now (it's simply returning ->i_private; would
    have been an inline, if not for header ordering headache).
    proc_ns_inode() is an ex-parrot.  The interface used in procfs is
    ns_get_path(path, task, ops) and ns_get_name(buf, size, task, ops).
    
    Dentries and inodes are never hashed; a non-counting reference to dentry
    is stashed in ns_common (removed by ->d_prune()) and reused by ns_get_path()
    if present.  See ns_get_path()/ns_prune_dentry/nsfs_evict() for details
    of that mechanism.
    
    As the result, proc_ns_follow_link() has stopped poking in nd->path.mnt;
    it does nd_jump_link() on a consistent <vfsmount,dentry> pair it gets
    from ns_get_path().
    Signed-off-by: 's avatarAl Viro <viro@zeniv.linux.org.uk>
    e149ed2b
ns_common.h 196 Bytes