Re: [PATCH] cifs: create a helper to find a writeable handle by path name

[Steve French <smfrench@gmail.com>]

Even so ... we shouldn't ask for open/query/close or
open/setinfo/close if just a query-info or set-info (no open/close) is
possible - it will make server's lives much easier ...

On Wed, Sep 11, 2019 at 3:06 PM Pavel Shilovsky <piastryyy@gmail.com> wrote:
>
> чт, 29 авг. 2019 г. в 15:26, Ronnie Sahlberg <lsahlber@redhat.com>:
> >
> > rename() takes a path for old_file and in SMB2 we used to just create
> > a compound for create(old_path)/rename/close().
> > If we already have a writable handle we can avoid the create() and close()
> > altogether and just use the existing handle.
> >
> > For this situation, as we avoid doing the create()
> > we also avoid triggering an oplock break for the existing handle.
>
> Hi Ronnie,
>
> Another SMB2_CREATE from the same client shouldn't cause a lease break
> if we ask for a lease with the same lease key. The lease key is
> associated with the inode, all opens that can cause a break should ask
> for the lease with the lease key.
>
> Currently smb2_compound_op doesn't ask for a lease: see at the
> beginning of the function:
>
> oplock = SMB2_OPLOCK_LEVEL_NONE
>
> What we need to do is to change this to SMB2_OPLOCK_LEVEL_BATCH for
> operation that modifies the file like SET_EOF and SET_INFO. In this
> case the lower layer will map it to the appropriate lease state. Note
> that parms->fid->lease_key should be populated.
>
> --
> Best regards,
> Pavel Shilovsky



-- 
Thanks,

Steve