Introduce an infrastructure for dismantling vnet instances.

Vnet modules and protocol domains may now register destructor
functions to clean up and release per-module state.  The destructor
mechanisms can be triggered by invoking "vimage -d", or a future
equivalent command which will be provided via the new jail framework.

While this patch introduces numerous placeholder destructor functions,
many of those are currently incomplete, thus leaking memory or (even
worse) failing to stop all running timers.  Many of such issues are
already known and will be incrementaly fixed over the next weeks in
smaller incremental commits.

Apart from introducing new fields in structs ifnet, domain, protosw
and vnet_net, which requires the kernel and modules to be rebuilt, this
change should have no impact on nooptions VIMAGE builds, since vnet
destructors can only be called in VIMAGE kernels.  Moreover,
destructor functions should be in general compiled in only in
options VIMAGE builds, except for kernel modules which can be safely
kldunloaded at run time.

Bump __FreeBSD_version to 800097.
Reviewed by:	bz, julian
Approved by:	rwatson, kib (re), julian (mentor)

1 files changed, 3 insertions, 0 deletions

diff --git a/sys/netinet/ip_var.h b/sys/netinet/ip_var.h
index aa9beb148b8f..1e5e693012c2 100644
--- a/sys/netinet/ip_var.h
+++ b/sys/netinet/ip_var.h
@@ -210,6 +210,9 @@ u_int16_t	ip_randomid(void);
 int	rip_ctloutput(struct socket *, struct sockopt *);
 void	rip_ctlinput(int, struct sockaddr *, void *);
 void	rip_init(void);
+#ifdef VIMAGE
+void	rip_destroy(void);
+#endif
 void	rip_input(struct mbuf *, int);
 int	rip_output(struct mbuf *, struct socket *, u_long);
 void	ipip_input(struct mbuf *, int);