Re: [RFC PATCH] client: don't use special inode for /..

[Jeff Layton <jlayton@redhat.com>]

On Wed, 2016-08-10 at 16:08 -0400, Patrick Donnelly wrote:
> On Wed, Aug 10, 2016 at 12:30 PM, Jeff Layton <jlayton@redhat.com>
> wrote:
> > 
> > The CEPH_INO_DOTDOT thing is quite strange. Under most OS (Linux
> > included), the parent of the root is itself. IOW, at the root, '.'
> > and
> > '..' refer to the same inode.
> > 
> > Change the ceph client to do the same, as this allows users to get
> > valid stat info for '..', as well as elimnating some special-
> > casing.
> > 
> > Signed-off-by: Jeff Layton <jlayton@redhat.com>
> 
> Don't forget Client::_lookup:
> 
>   if (dname == "..") {
>     if (dir->dn_set.empty())
>       r = -ENOENT;
>     else
>       *target = dir->get_first_parent()->dir->parent_inode; //dirs
> can't be hard-linked
>     goto done;
>   }
> 
> Otherwise LGTM.
> 


Ahh, thanks. So will dir->dn_set.empty() be true at the root? If so,
then something like the patch below?

Note that this patch is not strictly necessary, but it does simplify
some other changes that I have queued up:

diff --git a/src/client/Client.cc b/src/client/Client.cc
index 5ab0ace4d3df..287baaf20536 100644
--- a/src/client/Client.cc
+++ b/src/client/Client.cc
@@ -5924,7 +5924,7 @@ int Client::_lookup(Inode *dir, const string& dname, int mask,
 
   if (dname == "..") {
     if (dir->dn_set.empty())
-      r = -ENOENT;
+      *target = dir;
     else
       *target = dir->get_first_parent()->dir->parent_inode; //dirs can't be hard-linked
     goto done;


-- 
Jeff Layton <jlayton@redhat.com>