• Linus Torvalds's avatar
    vfs pathname lookup: Add LOOKUP_AUTOMOUNT flag · d94c177b
    Linus Torvalds authored
    
    
    Since we've now turned around and made LOOKUP_FOLLOW *not* force an
    automount, we want to add the ability to force an automount event on
    lookup even if we don't happen to have one of the other flags that force
    it implicitly (LOOKUP_OPEN, LOOKUP_DIRECTORY, LOOKUP_PARENT..)
    
    Most cases will never want to use this, since you'd normally want to
    delay automounting as long as possible, which usually implies
    LOOKUP_OPEN (when we open a file or directory, we really cannot avoid
    the automount any more).
    
    But Trond argued sufficiently forcefully that at a minimum bind mounting
    a file and quotactl will want to force the automount lookup.  Some other
    cases (like nfs_follow_remote_path()) could use it too, although
    LOOKUP_DIRECTORY would work there as well.
    
    This commit just adds the flag and logic, no users yet, though.  It also
    doesn't actually touch the LOOKUP_NO_AUTOMOUNT flag that is related, and
    was made irrelevant by the same change that made us not follow on
    LOOKUP_FOLLOW.
    
    Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
    Cc: Ian Kent <raven@themaw.net>
    Cc: Jeff Layton <jlayton@redhat.com>
    Cc: Miklos Szeredi <miklos@szeredi.hu>
    Cc: David Howells <dhowells@redhat.com>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: Greg KH <gregkh@suse.de>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    d94c177b