Re: Does ceph_fill_inode() mishandle I_NEW?

[David Howells <dhowells@redhat.com>]

Viacheslav Dubeyko <Slava.Dubeyko@ibm.com> wrote:

> As far as I can see, ceph_fill_inode() has comment: "Populate an inode based
> on info from mds. May be called on new or existing inodes". It sounds to me
> that particular CephFS kernel client could have obsolete state of inode
> compared with MDS's state. And we need to "re-new" the existing inode with
> the actual state that we received from MDS side. My vision is that we need
> to take into account the distributed nature of Ceph and inode metadata can
> be updated from multiple CephFS kernel client instances. Am I right here?

As I mentioned in my reply to Jeff, I'm thinking of what happens in the event
that we have a file that has hard links in several directories in a situation
where several of those links are looked up simultaneously.  Can we end up with
ceph_fill_inode() being run in parallel on several threads on the same inode?

Actually, the use of ci->i_ceph_lock looks like it should make it safe, now
that I look at it again.

David