freebsd-nq/sys/net/if_dead.c
John Baldwin c782ea8bb5 Add a switch structure for send tags.
Move the type and function pointers for operations on existing send
tags (modify, query, next, free) out of 'struct ifnet' and into a new
'struct if_snd_tag_sw'.  A pointer to this structure is added to the
generic part of send tags and is initialized by m_snd_tag_init()
(which now accepts a switch structure as a new argument in place of
the type).

Previously, device driver ifnet methods switched on the type to call
type-specific functions.  Now, those type-specific functions are saved
in the switch structure and invoked directly.  In addition, this more
gracefully permits multiple implementations of the same tag within a
driver.  In particular, NIC TLS for future Chelsio adapters will use a
different implementation than the existing NIC TLS support for T6
adapters.

Reviewed by:	gallatin, hselasky, kib (older version)
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D31572
2021-09-14 11:43:41 -07:00

144 lines
3.4 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2009 Robert N. M. Watson
* 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.
*/
/*
* When an interface has been detached but not yet freed, we set the various
* ifnet function pointers to "ifdead" versions. This prevents unexpected
* calls from the network stack into the device driver after if_detach() has
* returned.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_var.h>
static int
ifdead_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa,
struct route *ro)
{
m_freem(m);
return (ENXIO);
}
static void
ifdead_input(struct ifnet *ifp, struct mbuf *m)
{
m_freem(m);
}
static void
ifdead_start(struct ifnet *ifp)
{
}
static int
ifdead_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
return (ENXIO);
}
static int
ifdead_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa,
struct sockaddr *sa)
{
*llsa = NULL;
return (ENXIO);
}
static void
ifdead_qflush(struct ifnet *ifp)
{
}
static int
ifdead_transmit(struct ifnet *ifp, struct mbuf *m)
{
m_freem(m);
return (ENXIO);
}
static uint64_t
ifdead_get_counter(struct ifnet *ifp, ift_counter cnt)
{
return (0);
}
static int
ifdead_snd_tag_alloc(struct ifnet *ifp, union if_snd_tag_alloc_params *params,
struct m_snd_tag **ppmt)
{
return (EOPNOTSUPP);
}
static void
ifdead_ratelimit_query(struct ifnet *ifp __unused,
struct if_ratelimit_query_results *q)
{
/*
* This guy does not support
* this interface. Not sure
* why we would specify a
* flag on the interface
* that says we do.
*/
q->rate_table = NULL;
q->flags = RT_NOSUPPORT;
q->max_flows = 0;
q->number_of_rates = 0;
}
void
if_dead(struct ifnet *ifp)
{
ifp->if_output = ifdead_output;
ifp->if_input = ifdead_input;
ifp->if_start = ifdead_start;
ifp->if_ioctl = ifdead_ioctl;
ifp->if_resolvemulti = ifdead_resolvemulti;
ifp->if_qflush = ifdead_qflush;
ifp->if_transmit = ifdead_transmit;
ifp->if_get_counter = ifdead_get_counter;
ifp->if_snd_tag_alloc = ifdead_snd_tag_alloc;
ifp->if_ratelimit_query = ifdead_ratelimit_query;
}