From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NUQH3-0005VP-5D for qemu-devel@nongnu.org; Mon, 11 Jan 2010 14:50:01 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NUQGy-0005QE-Ek for qemu-devel@nongnu.org; Mon, 11 Jan 2010 14:50:00 -0500 Received: from [199.232.76.173] (port=33991 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NUQGy-0005Q6-7x for qemu-devel@nongnu.org; Mon, 11 Jan 2010 14:49:56 -0500 Received: from mail-qy0-f189.google.com ([209.85.221.189]:54019) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NUQGx-00033C-S8 for qemu-devel@nongnu.org; Mon, 11 Jan 2010 14:49:56 -0500 Received: by qyk27 with SMTP id 27so9583154qyk.20 for ; Mon, 11 Jan 2010 11:49:55 -0800 (PST) Message-ID: <4B4B80DE.4050607@codemonkey.ws> Date: Mon, 11 Jan 2010 13:49:50 -0600 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH] [tftp] Handle TFTP ERROR from client References: <20100107170128.6751.qmail@jehova.dsm.dk> In-Reply-To: <20100107170128.6751.qmail@jehova.dsm.dk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thomas Horsten Cc: qemu-devel@nongnu.org On 01/07/2010 11:01 AM, Thomas Horsten wrote: > If a PXE client only wants to find out the size of a file, it will > open the file and then abort the transfer by sending a TFTP ERROR packet. > > The ERROR packet should cause qemu to terminate the session. If not, > the sessions will soon run out and cause timeouts in the client. > > Also, if a TFTP session already exists with same IP/UDP port, it > should be terminated when a new RRQ is received, instead of creating a > duplicate (which will never be used). > > A patch for gPXE to send the ERROR packet is also being submitted to > gPXE. Together they resolve slowness/hanging when booting pxegrub from > qemu's internal TFTP server. The patch from Milan Plzik to return > after sending OACK is also required for a complete fix. > > Signed-off-by: Thomas Horsten > Signed-off-by: Milan Plzik > Applied. Thanks. Regards, Anthony Liguori > --- > slirp/tftp.c | 23 +++++++++++++++++++++++ > 1 files changed, 23 insertions(+), 0 deletions(-) > > diff --git a/slirp/tftp.c b/slirp/tftp.c > index db869fc..96c0e0c 100644 > --- a/slirp/tftp.c > +++ b/slirp/tftp.c > @@ -264,6 +264,12 @@ static void tftp_handle_rrq(Slirp *slirp, struct tftp_t *tp, int pktlen) > size_t prefix_len; > char *req_fname; > > + /* check if a session already exists and if so terminate it */ > + s = tftp_session_find(slirp, tp); > + if (s>= 0) { > + tftp_session_terminate(&slirp->tftp_sessions[s]); > + } > + > s = tftp_session_allocate(slirp, tp); > > if (s< 0) { > @@ -386,6 +392,19 @@ static void tftp_handle_ack(Slirp *slirp, struct tftp_t *tp, int pktlen) > } > } > > +static void tftp_handle_error(Slirp *slirp, struct tftp_t *tp, int pktlen) > +{ > + int s; > + > + s = tftp_session_find(slirp, tp); > + > + if (s< 0) { > + return; > + } > + > + tftp_session_terminate(&slirp->tftp_sessions[s]); > +} > + > void tftp_input(struct mbuf *m) > { > struct tftp_t *tp = (struct tftp_t *)m->m_data; > @@ -398,5 +417,9 @@ void tftp_input(struct mbuf *m) > case TFTP_ACK: > tftp_handle_ack(m->slirp, tp, m->m_len); > break; > + > + case TFTP_ERROR: > + tftp_handle_error(m->slirp, tp, m->m_len); > + break; > } > } >