freebsd-dev/sys/netinet/tcp_offload.c
Navdeep Parhar 01d74fe1ff Path MTU discovery hooks for offloaded TCP connections.
Notify the TOE driver when when an ICMP type 3 code 4 (Fragmentation
needed and DF set) message is received for an offloaded connection.
This gives the driver an opportunity to lower the path MTU for the
connection and resume transmission, much like what the kernel does for
the connections that it handles.

Reviewed by:	glebius@
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D29755
2021-04-21 13:00:16 -07:00

233 lines
5.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2012 Chelsio Communications, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/eventhandler.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockopt.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/route/nhop.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/in_fib.h>
#include <netinet6/in6_fib.h>
#include <netinet/tcp.h>
#include <netinet/tcp_offload.h>
#define TCPOUTFLAGS
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_var.h>
#include <netinet/toecore.h>
int registered_toedevs;
/*
* Provide an opportunity for a TOE driver to offload.
*/
int
tcp_offload_connect(struct socket *so, struct sockaddr *nam)
{
struct ifnet *ifp;
struct toedev *tod;
struct nhop_object *nh;
struct epoch_tracker et;
int error = EOPNOTSUPP;
INP_WLOCK_ASSERT(sotoinpcb(so));
KASSERT(nam->sa_family == AF_INET || nam->sa_family == AF_INET6,
("%s: called with sa_family %d", __func__, nam->sa_family));
if (registered_toedevs == 0)
return (error);
NET_EPOCH_ENTER(et);
nh = NULL;
#ifdef INET
if (nam->sa_family == AF_INET)
nh = fib4_lookup(0, ((struct sockaddr_in *)nam)->sin_addr,
NHR_NONE, 0, 0);
#endif
#if defined(INET) && defined(INET6)
else
#endif
#ifdef INET6
if (nam->sa_family == AF_INET6)
nh = fib6_lookup(0, &((struct sockaddr_in6 *)nam)->sin6_addr,
NHR_NONE, 0, 0);
#endif
if (nh == NULL) {
NET_EPOCH_EXIT(et);
return (EHOSTUNREACH);
}
ifp = nh->nh_ifp;
if (nam->sa_family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4))
goto done;
if (nam->sa_family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6))
goto done;
tod = TOEDEV(ifp);
if (tod != NULL)
error = tod->tod_connect(tod, so, nh, nam);
done:
NET_EPOCH_EXIT(et);
return (error);
}
void
tcp_offload_listen_start(struct tcpcb *tp)
{
INP_WLOCK_ASSERT(tp->t_inpcb);
EVENTHANDLER_INVOKE(tcp_offload_listen_start, tp);
}
void
tcp_offload_listen_stop(struct tcpcb *tp)
{
INP_WLOCK_ASSERT(tp->t_inpcb);
EVENTHANDLER_INVOKE(tcp_offload_listen_stop, tp);
}
void
tcp_offload_input(struct tcpcb *tp, struct mbuf *m)
{
struct toedev *tod = tp->tod;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
tod->tod_input(tod, tp, m);
}
int
tcp_offload_output(struct tcpcb *tp)
{
struct toedev *tod = tp->tod;
int error, flags;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
flags = tcp_outflags[tp->t_state];
if (flags & TH_RST) {
/* XXX: avoid repeated calls like we do for FIN */
error = tod->tod_send_rst(tod, tp);
} else if ((flags & TH_FIN || tp->t_flags & TF_NEEDFIN) &&
(tp->t_flags & TF_SENTFIN) == 0) {
error = tod->tod_send_fin(tod, tp);
if (error == 0)
tp->t_flags |= TF_SENTFIN;
} else
error = tod->tod_output(tod, tp);
return (error);
}
void
tcp_offload_rcvd(struct tcpcb *tp)
{
struct toedev *tod = tp->tod;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
tod->tod_rcvd(tod, tp);
}
void
tcp_offload_ctloutput(struct tcpcb *tp, int sopt_dir, int sopt_name)
{
struct toedev *tod = tp->tod;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
tod->tod_ctloutput(tod, tp, sopt_dir, sopt_name);
}
void
tcp_offload_tcp_info(struct tcpcb *tp, struct tcp_info *ti)
{
struct toedev *tod = tp->tod;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
tod->tod_tcp_info(tod, tp, ti);
}
int
tcp_offload_alloc_tls_session(struct tcpcb *tp, struct ktls_session *tls,
int direction)
{
struct toedev *tod = tp->tod;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
return (tod->tod_alloc_tls_session(tod, tp, tls, direction));
}
void
tcp_offload_detach(struct tcpcb *tp)
{
struct toedev *tod = tp->tod;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
tod->tod_pcb_detach(tod, tp);
}
void
tcp_offload_pmtu_update(struct tcpcb *tp, tcp_seq seq, int mtu)
{
struct toedev *tod = tp->tod;
KASSERT(tod != NULL, ("%s: tp->tod is NULL, tp %p", __func__, tp));
INP_WLOCK_ASSERT(tp->t_inpcb);
tod->tod_pmtu_update(tod, tp, seq, mtu);
}