Re: [PATCH 1/2] SUNRPC: track when a client connection is routed to the local host.

[NeilBrown <neilb@suse.de>]

[-- Attachment #1: Type: text/plain, Size: 2323 bytes --]

On Wed, 20 Aug 2014 20:33:04 -0400 Trond Myklebust
<trond.myklebust@primarydata.com> wrote:

> On Mon, 2014-08-18 at 16:22 +1000, NeilBrown wrote:
> > If requests are being sent to the local host, then NFS will
> > need to take care to avoid deadlocks.
> > 
> > So keep track when accepting a connection or sending a UDP request
> > and set a flag in the svc_xprt when the peer connected to is local.
> > 
> > The interface rpc_is_foreign() is provided to check is a given client
> > is connected to a foreign server.  When it returns zero it is either
> > not connected or connected to a local server and in either case
> > greater care is needed.
> > 
> > Signed-off-by: NeilBrown <neilb@suse.de>
> > ---
> >  include/linux/sunrpc/clnt.h |    1 +
> >  include/linux/sunrpc/xprt.h |    1 +
> >  net/sunrpc/clnt.c           |   25 +++++++++++++++++++++++++
> >  net/sunrpc/xprtsock.c       |    9 +++++++++
> >  4 files changed, 36 insertions(+)
> > 
> > diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
> > index 70736b98c721..cd79b2a28ceb 100644
> > --- a/include/linux/sunrpc/clnt.h
> > +++ b/include/linux/sunrpc/clnt.h
> > @@ -175,6 +175,7 @@ void		rpc_force_rebind(struct rpc_clnt *);
> >  size_t		rpc_peeraddr(struct rpc_clnt *, struct sockaddr *, size_t);
> >  const char	*rpc_peeraddr2str(struct rpc_clnt *, enum rpc_display_format_t);
> >  int		rpc_localaddr(struct rpc_clnt *, struct sockaddr *, size_t);
> > +int		rpc_is_foreign(struct rpc_clnt *);
> >  
> >  #endif /* __KERNEL__ */
> >  #endif /* _LINUX_SUNRPC_CLNT_H */
> > diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
> > index fcbfe8783243..6a9dffcb9d3f 100644
> > --- a/include/linux/sunrpc/xprt.h
> > +++ b/include/linux/sunrpc/xprt.h
> > @@ -357,6 +357,7 @@ int			xs_swapper(struct rpc_xprt *xprt, int enable);
> >  #define XPRT_CONNECTION_ABORT	(7)
> >  #define XPRT_CONNECTION_CLOSE	(8)
> >  #define XPRT_CONGESTED		(9)
> > +#define XPRT_LOCAL		(10)
> >  
> 
> Can we please rename that to XPRT_LOOPBACK or something along those
> lines? To me XPRT_LOCAL looks a little too close for comfort to
> AF_LOCAL, which is also a supported transport.
> 

I'm fine with that.  I'll resend once we are in agreement about the other
bits.

Thanks,
NeilBrown

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]