Introduce and use a sysinit-based initialization scheme for virtual

network stacks, VNET_SYSINIT:

- Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will
  occur each time a network stack is instantiated and destroyed.  In the
  !VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT.
  For the VIMAGE case, we instead use SYSINIT's to track their order and
  properties on registration, using them for each vnet when created/
  destroyed, or immediately on module load for already-started vnets.
- Remove vnet_modinfo mechanism that existed to serve this purpose
  previously, as well as its dependency scheme: we now just use the
  SYSINIT ordering scheme.
- Implement VNET_DOMAIN_SET() to allow protocol domains to declare that
  they want init functions to be called for each virtual network stack
  rather than just once at boot, compiling down to DOMAIN_SET() in the
  non-VIMAGE case.
- Walk all virtualized kernel subsystems and make use of these instead
  of modinfo or DOMAIN_SET() for init/uninit events.  In some cases,
  convert modular components from using modevent to using sysinit (where
  appropriate).  In some cases, do minor rejuggling of SYSINIT ordering
  to make room for or better manage events.

Portions submitted by:	jhb (VNET_SYSINIT), bz (cleanup)
Discussed with:		jhb, bz, julian, zec
Reviewed by:		bz
Approved by:		re (VIMAGE blanket)

1 files changed, 12 insertions, 40 deletions

diff --git a/sys/netinet/igmp.c b/sys/netinet/igmp.c
index 2c7ed2e..44796de 100644
--- a/sys/netinet/igmp.c
+++ b/sys/netinet/igmp.c
@@ -114,7 +114,6 @@ static char *	igmp_rec_type_to_str(const int);
 #endif
 static void	igmp_set_version(struct igmp_ifinfo *, const int);
 static void	igmp_slowtimo_vnet(void);
-static void	igmp_sysinit(void);
 static int	igmp_v1v2_queue_report(struct in_multi *, const int);
 static void	igmp_v1v2_process_group_timer(struct in_multi *, const int);
 static void	igmp_v1v2_process_querier_timers(struct igmp_ifinfo *);
@@ -137,9 +136,6 @@ static int	sysctl_igmp_default_version(SYSCTL_HANDLER_ARGS);
 static int	sysctl_igmp_gsr(SYSCTL_HANDLER_ARGS);
 static int	sysctl_igmp_ifinfo(SYSCTL_HANDLER_ARGS);
 
-static vnet_attach_fn	vnet_igmp_iattach;
-static vnet_detach_fn	vnet_igmp_idetach;
-
 static const struct netisr_handler igmp_nh = {
 	.nh_name = "igmp",
 	.nh_handler = igmp_intr,
@@ -3580,7 +3576,7 @@ igmp_rec_type_to_str(const int type)
 #endif
 
 static void
-igmp_sysinit(void)
+igmp_init(void *unused __unused)
 {
 
 	CTR1(KTR_IGMPV3, "%s: initializing", __func__);
@@ -3591,9 +3587,10 @@ igmp_sysinit(void)
 
 	netisr_register(&igmp_nh);
 }
+SYSINIT(igmp_init, SI_SUB_PSEUDO, SI_ORDER_MIDDLE, igmp_init, NULL);
 
 static void
-igmp_sysuninit(void)
+igmp_uninit(void *unused __unused)
 {
 
 	CTR1(KTR_IGMPV3, "%s: tearing down", __func__);
@@ -3605,42 +3602,30 @@ igmp_sysuninit(void)
 
 	IGMP_LOCK_DESTROY();
 }
+SYSUNINIT(igmp_uninit, SI_SUB_PSEUDO, SI_ORDER_MIDDLE, igmp_uninit, NULL);
 
-/*
- * Initialize an IGMPv3 instance.
- * VIMAGE: Assumes curvnet set by caller and called per vimage.
- */
-static int
-vnet_igmp_iattach(const void *unused __unused)
+static void
+vnet_igmp_init(const void *unused __unused)
 {
 
 	CTR1(KTR_IGMPV3, "%s: initializing", __func__);
 
 	LIST_INIT(&V_igi_head);
-
-	return (0);
 }
+VNET_SYSINIT(vnet_igmp_init, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_igmp_init,
+    NULL);
 
-static int
-vnet_igmp_idetach(const void *unused __unused)
+static void
+vnet_igmp_uninit(const void *unused __unused)
 {
 
 	CTR1(KTR_IGMPV3, "%s: tearing down", __func__);
 
 	KASSERT(LIST_EMPTY(&V_igi_head),
 	    ("%s: igi list not empty; ifnets not detached?", __func__));
-
-	return (0);
 }
-
-#ifdef VIMAGE
-static vnet_modinfo_t vnet_igmp_modinfo = {
-	.vmi_id		= VNET_MOD_IGMP,
-	.vmi_name	= "igmp",
-	.vmi_iattach	= vnet_igmp_iattach,
-	.vmi_idetach	= vnet_igmp_idetach
-};
-#endif
+VNET_SYSUNINIT(vnet_igmp_uninit, SI_SUB_PSEUDO, SI_ORDER_ANY,
+    vnet_igmp_uninit, NULL);
 
 static int
 igmp_modevent(module_t mod, int type, void *unused __unused)
@@ -3648,20 +3633,7 @@ igmp_modevent(module_t mod, int type, void *unused __unused)
 
     switch (type) {
     case MOD_LOAD:
-	igmp_sysinit();
-#ifdef VIMAGE
-	vnet_mod_register(&vnet_igmp_modinfo);
-#else
-	vnet_igmp_iattach(NULL);
-#endif
-	break;
     case MOD_UNLOAD:
-#ifdef VIMAGE
-	vnet_mod_deregister(&vnet_igmp_modinfo);
-#else
-	vnet_igmp_idetach(NULL);
-#endif
-	igmp_sysuninit();
 	break;
     default:
 	return (EOPNOTSUPP);