On Mon, 2011-09-26 at 20:57 -0700, Linus Torvalds wrote: > On Mon, Sep 26, 2011 at 5:59 PM, Trond Myklebust > <Trond.Myklebust@xxxxxxxxxx> wrote: > > diff --git a/fs/namei.c b/fs/namei.c > > index f478836..5b1608f 100644 > > --- a/fs/namei.c > > +++ b/fs/namei.c > > @@ -724,25 +724,9 @@ static int follow_automount(struct path *path, unsigned flags, > > /* We don't want to mount if someone supplied AT_NO_AUTOMOUNT > > * and this is the terminal part of the path. > > */ > > - if ((flags & LOOKUP_NO_AUTOMOUNT) && !(flags & LOOKUP_PARENT)) > > + if (!(flags & LOOKUP_AUTOMOUNT) && !(flags & LOOKUP_PARENT)) > > return -EISDIR; /* we actually want to stop here */ > > > > - /* We don't want to mount if someone's just doing a stat - > > - * unless they're stat'ing a directory and appended a '/' to > > - * the name. > > - * > > - * We do, however, want to mount if someone wants to open or > > - * create a file of any type under the mountpoint, wants to > > - * traverse through the mountpoint or wants to open the > > - * mounted directory. Also, autofs may mark negative dentries > > - * as being automount points. These will need the attentions > > - * of the daemon to instantiate them before they can be used. > > - */ > > - if (!(flags & (LOOKUP_PARENT | LOOKUP_DIRECTORY | > > - LOOKUP_OPEN | LOOKUP_CREATE)) && > > - path->dentry->d_inode) > > - return -EISDIR; > > - > > current->total_link_count++; > > if (current->total_link_count >= 40) > > return -ELOOP; > > So I think that dropping the d_inode test is wrong, even if we were to > at some point decide that we want explicit LOOKUP_AUTOMOUNT > everywhere. > > Of course, it may be that the comment is wrong. But assuming the > comment is correct, then it's really the test above that is > fundamentally wrong. > > Ian may know the answer. Ian? Yes, I saw that but got side tracked by the email exchanges of last night. This case is the one were there is no existing directory yet for the automount (it's the age old original automount case where mount point directories never existed within the automount managed directory before being automounted). In this case we always want to automount regardless of the lookup flags. So returning -EISDIR should be conditional on also having a positive dentry. Ian -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
