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author | rwatson <rwatson@FreeBSD.org> | 2009-04-23 11:51:53 +0000 |
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committer | rwatson <rwatson@FreeBSD.org> | 2009-04-23 11:51:53 +0000 |
commit | ccc05d4c7fc358ca3cc8339274b58835f1ba153b (patch) | |
tree | 00a3b8317138c3f76378e3a6003faf4f48043892 /sys/net/if_dead.c | |
parent | bf5b2167ac0cacf1ff816efc0f73ed8e20386341 (diff) | |
download | FreeBSD-src-ccc05d4c7fc358ca3cc8339274b58835f1ba153b.zip FreeBSD-src-ccc05d4c7fc358ca3cc8339274b58835f1ba153b.tar.gz |
During if_detach(), invoke if_dead() to set the ifnet's function
pointers to "dead" implementations that no-op rather than invoking
the device driver. This would generally be unexpected and
possibly quite badly handled by most device drivers after
if_detach() has completed.
Reviewed by: bms
MFC after: 3 weeks
Diffstat (limited to 'sys/net/if_dead.c')
-rw-r--r-- | sys/net/if_dead.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/sys/net/if_dead.c b/sys/net/if_dead.c new file mode 100644 index 0000000..b28ffc2 --- /dev/null +++ b/sys/net/if_dead.c @@ -0,0 +1,114 @@ +/*- + * 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, 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 void +ifdead_watchdog(struct ifnet *ifp) +{ + +} + +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); +} + +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_watchdog = ifdead_watchdog; + ifp->if_resolvemulti = ifdead_resolvemulti; + ifp->if_qflush = ifdead_qflush; + ifp->if_transmit = ifdead_transmit; +} |