[linux-cifs-client] Problems with rename to open file and open/unlink/create

[Jeff Layton]

On Tue, 7 Apr 2009 08:03:56 +0200
Wilhelm Meier <wilhelm.meier at fh-kl.de> wrote:

> Am Montag 06 April 2009 schrieb Jeff Layton:
> > On Mon, 6 Apr 2009 17:18:30 +0200
> >
> > Wilhelm Meier <wilhelm.meier at fh-kl.de> wrote:
> > > Hi all,
> > >
> > > we use a cifs-1.56 (the backported sources from Steve French)
> > > together with a 2.6.27-kernel. As we encounter some weired
> > > problems with kmail, I took my cifs-test-programs (see
> > > attchements) and I got strange results.
> > >
> > > 1) t_byterangelocking: all fine
> > >
> > > 2) t_rename: test ok, but leaves around cifsXXXX-files
> > >
> > > 3) t_openunlinkclose: test ok, but leaves also around
> > > cifsXXX-files
> > >
> > > Below you find the /proc/mounts and DebugData.
> > >
> > > I think the cifsXXXX files are the cause of problems to kmail.
> > > Do you have any ideas?
> > >
> > > Thx,
> > >
> > > Wilhelm
> > >
> > > //kmux-svc/kmux.admin /home/kmux.admin cifs
> > > rw,unc=\\kmux-svc\kmux.admin,username=kmux.admin,domain=kmux,addr
> > >=192.168.32.12,uid=999,gid=999,posixpaths,serverino,nobrl,acl,rsiz
> > >e=16384,wsize=57344 0 0
> > >
> > > kmux.admin at rich00018061EBDD:~$ cat /proc/fs/cifs/DebugData
> > > Display Internal CIFS Data Structures for Debugging
> > > ---------------------------------------------------
> > > CIFS Version 1.56
> > > Active VFS Requests: 0
> > > Servers:
> > > 1) Name: 192.168.32.12  Domain: KMUX Uses: 4 OS: Unix
> > >         NOS: Samba 3.0.28a      Capability: 0x80e3fd
> >
> > 		^^^^^^^^^^^
> > I think that this version of samba may not handle the
> > delete_on_close bit properly. I ran across this when trying to fix
> > this code and left some comments to that effect:
> 
> Well, I tested also will samba-3.3.2 (ubuntu package) and samba-3.3.3 
> (compiled).
> 
> Now the t_rename succeeds, but t_openunlinkclose still produces 
> cifsXXXX files. Yes, and kmail keeps crashing.
> 
> I read something about the readdir implementation in cifs >= 1.56, but 
> this seems not to the case in the 
> 
> http://pserver.samba.org/samba/ftp/cifs-cvs/cifs-1.56-backport-for-2.6.25-2.6.28.tar.gz
> 
> backport I used here for the 2.6.27-kernel. Are there any cifs-1.57 
> versions backported to linux-2.6.27?
> 

You may want to test a more recent kernel as well. It's possible the
backported cifs module you're using doesn't handle this properly.
Deleting and renaming open files with CIFS is extremely tricky and we
went through several iterations before we got to the current state in
upstream code. I'm not convinced that it's quite correct yet (a
spurious reconnect in the middle of operations could lead to the file
getting deleted on the server), but it works well enough to pass the
connectathon tests now.

If you can reproduce on a recent kernel (2.6.29-ish, ideally) then
please open a samba.org BZ, cc me on it and detail how you're
reproducing it.

-- 
Jeff Layton <jlayton at redhat.com>