Build on Jeff Roberson's linker-set based dynamic per-CPU allocator

(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)

1 files changed, 9 insertions, 82 deletions

diff --git a/sys/netinet/ip_fw.h b/sys/netinet/ip_fw.h
index 9e3468f..609ac4c 100644
--- a/sys/netinet/ip_fw.h
+++ b/sys/netinet/ip_fw.h
@@ -651,12 +651,14 @@ void ipfw_destroy(void);
 void ipfw_nat_destroy(void);
 #endif
 
-#ifdef VIMAGE_GLOBALS
-extern int fw_one_pass;
-extern int fw_enable;
+VNET_DECLARE(int, fw_one_pass);
+VNET_DECLARE(int, fw_enable);
+#define	V_fw_one_pass		VNET_GET(fw_one_pass)
+#define	V_fw_enable		VNET_GET(fw_enable)
+
 #ifdef INET6
-extern int fw6_enable;
-#endif
+VNET_DECLARE(int, fw6_enable);
+#define	V_fw6_enable		VNET_GET(fw6_enable)
 #endif
 
 struct ip_fw_chain {
@@ -692,83 +694,8 @@ typedef int ipfw_nat_t(struct ip_fw_args *, struct cfg_nat *, struct mbuf *);
 typedef int ipfw_nat_cfg_t(struct sockopt *);
 #endif
 
-struct eventhandler_entry;
-/*
- * Stack virtualization support.
- */
-struct vnet_ipfw {
-	int			_fw_enable;
-	int			_fw6_enable;
-	u_int32_t		_set_disable;
-	int			_fw_deny_unknown_exthdrs;
-	int			_fw_verbose;
-	int			_verbose_limit;
-	int			_autoinc_step;
-	ipfw_dyn_rule **	_ipfw_dyn_v;
-	uma_zone_t 		_ipfw_dyn_rule_zone;
-	struct ip_fw_chain	_layer3_chain;
-	u_int32_t		_dyn_buckets;
-	u_int32_t		_curr_dyn_buckets;
-	u_int32_t		_dyn_ack_lifetime;
-	u_int32_t		_dyn_syn_lifetime;
-	u_int32_t		_dyn_fin_lifetime;
-	u_int32_t		_dyn_rst_lifetime;
-	u_int32_t		_dyn_udp_lifetime;
-	u_int32_t		_dyn_short_lifetime;
-	u_int32_t		_dyn_keepalive_interval;
-	u_int32_t		_dyn_keepalive_period;
-	u_int32_t		_dyn_keepalive;
-	u_int32_t		_static_count;
-	u_int32_t		_static_len;
-	u_int32_t		_dyn_count;
-	u_int32_t		_dyn_max;
-	u_int64_t		_norule_counter;
-	struct callout		_ipfw_timeout;
-	struct eventhandler_entry *_ifaddr_event_tag;
-};
-
-#ifndef VIMAGE
-#ifndef VIMAGE_GLOBALS
-extern struct vnet_ipfw vnet_ipfw_0;
-#endif
-#endif
-
-/*
- * Symbol translation macros
- */
-#define	INIT_VNET_IPFW(vnet) \
-	INIT_FROM_VNET(vnet, VNET_MOD_IPFW, struct vnet_ipfw, vnet_ipfw)
- 
-#define	VNET_IPFW(sym)		VSYM(vnet_ipfw, sym)
- 
-#define	V_fw_enable		VNET_IPFW(fw_enable)
-#define	V_fw6_enable		VNET_IPFW(fw6_enable)
-#define	V_set_disable		VNET_IPFW(set_disable)
-#define	V_fw_deny_unknown_exthdrs VNET_IPFW(fw_deny_unknown_exthdrs)
-#define	V_fw_verbose		VNET_IPFW(fw_verbose)
-#define	V_verbose_limit		VNET_IPFW(verbose_limit)
-#define	V_autoinc_step		VNET_IPFW(autoinc_step)
-#define	V_ipfw_dyn_v		VNET_IPFW(ipfw_dyn_v)
-#define	V_ipfw_dyn_rule_zone	VNET_IPFW(ipfw_dyn_rule_zone)
-#define	V_layer3_chain		VNET_IPFW(layer3_chain)
-#define	V_dyn_buckets		VNET_IPFW(dyn_buckets)
-#define	V_curr_dyn_buckets	VNET_IPFW(curr_dyn_buckets)
-#define	V_dyn_ack_lifetime	VNET_IPFW(dyn_ack_lifetime)
-#define	V_dyn_syn_lifetime	VNET_IPFW(dyn_syn_lifetime)
-#define	V_dyn_fin_lifetime	VNET_IPFW(dyn_fin_lifetime)
-#define	V_dyn_rst_lifetime	VNET_IPFW(dyn_rst_lifetime)
-#define	V_dyn_udp_lifetime	VNET_IPFW(dyn_udp_lifetime)
-#define	V_dyn_short_lifetime	VNET_IPFW(dyn_short_lifetime)
-#define	V_dyn_keepalive_interval VNET_IPFW(dyn_keepalive_interval)
-#define	V_dyn_keepalive_period	VNET_IPFW(dyn_keepalive_period)
-#define	V_dyn_keepalive		VNET_IPFW(dyn_keepalive)
-#define	V_static_count		VNET_IPFW(static_count)
-#define	V_static_len		VNET_IPFW(static_len)
-#define	V_dyn_count		VNET_IPFW(dyn_count)
-#define	V_dyn_max		VNET_IPFW(dyn_max)
-#define	V_norule_counter	VNET_IPFW(norule_counter)
-#define	V_ipfw_timeout		VNET_IPFW(ipfw_timeout)
-#define	V_ifaddr_event_tag	VNET_IPFW(ifaddr_event_tag)
+VNET_DECLARE(struct ip_fw_chain, layer3_chain);
+#define	V_layer3_chain		VNET_GET(layer3_chain)
 
 #endif /* _KERNEL */
 #endif /* _IPFW2_H */