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, 42 insertions, 50 deletions

diff --git a/sys/netinet/in_pcb.c b/sys/netinet/in_pcb.c
index 958e6b6..58bf77a 100644
--- a/sys/netinet/in_pcb.c
+++ b/sys/netinet/in_pcb.c
@@ -70,11 +70,9 @@ __FBSDID("$FreeBSD$");
 #include <netinet/tcp_var.h>
 #include <netinet/udp.h>
 #include <netinet/udp_var.h>
-#include <netinet/vinet.h>
 #ifdef INET6
 #include <netinet/ip6.h>
 #include <netinet6/ip6_var.h>
-#include <netinet6/vinet6.h>
 #endif /* INET6 */
 
 
@@ -85,34 +83,34 @@ __FBSDID("$FreeBSD$");
 
 #include <security/mac/mac_framework.h>
 
-#ifdef VIMAGE_GLOBALS
 /*
  * These configure the range of local port addresses assigned to
  * "unspecified" outgoing connections/packets/whatever.
  */
-int	ipport_lowfirstauto;
-int	ipport_lowlastauto;
-int	ipport_firstauto;
-int	ipport_lastauto;
-int	ipport_hifirstauto;
-int	ipport_hilastauto;
+VNET_DEFINE(int, ipport_lowfirstauto) = IPPORT_RESERVED - 1;	/* 1023 */
+VNET_DEFINE(int, ipport_lowlastauto) = IPPORT_RESERVEDSTART;	/* 600 */
+VNET_DEFINE(int, ipport_firstauto) = IPPORT_EPHEMERALFIRST;	/* 10000 */
+VNET_DEFINE(int, ipport_lastauto) = IPPORT_EPHEMERALLAST;	/* 65535 */
+VNET_DEFINE(int, ipport_hifirstauto) = IPPORT_HIFIRSTAUTO;	/* 49152 */
+VNET_DEFINE(int, ipport_hilastauto) = IPPORT_HILASTAUTO;	/* 65535 */
 
 /*
  * Reserved ports accessible only to root. There are significant
  * security considerations that must be accounted for when changing these,
  * but the security benefits can be great. Please be careful.
  */
-int	ipport_reservedhigh;
-int	ipport_reservedlow;
+VNET_DEFINE(int, ipport_reservedhigh) = IPPORT_RESERVED - 1;	/* 1023 */
+VNET_DEFINE(int, ipport_reservedlow);
 
 /* Variables dealing with random ephemeral port allocation. */
-int	ipport_randomized;
-int	ipport_randomcps;
-int	ipport_randomtime;
-int	ipport_stoprandom;
-int	ipport_tcpallocs;
-int	ipport_tcplastcount;
-#endif
+VNET_DEFINE(int, ipport_randomized) = 1;	/* user controlled via sysctl */
+VNET_DEFINE(int, ipport_randomcps) = 10;	/* user controlled via sysctl */
+VNET_DEFINE(int, ipport_randomtime) = 45;	/* user controlled via sysctl */
+VNET_DEFINE(int, ipport_stoprandom);		/* toggled by ipport_tick */
+VNET_DEFINE(int, ipport_tcpallocs);
+static VNET_DEFINE(int, ipport_tcplastcount);
+
+#define	V_ipport_tcplastcount		VNET_GET(ipport_tcplastcount)
 
 #define RANGECHK(var, min, max) \
 	if ((var) < (min)) { (var) = (min); } \
@@ -123,12 +121,13 @@ static void	in_pcbremlists(struct inpcb *inp);
 static int
 sysctl_net_ipport_check(SYSCTL_HANDLER_ARGS)
 {
-	INIT_VNET_INET(curvnet);
 	int error;
 
-	SYSCTL_RESOLVE_V_ARG1();
-
+#ifdef VIMAGE
+	error = vnet_sysctl_handle_int(oidp, arg1, arg2, req);
+#else
 	error = sysctl_handle_int(oidp, arg1, arg2, req);
+#endif
 	if (error == 0) {
 		RANGECHK(V_ipport_lowfirstauto, 1, IPPORT_RESERVED - 1);
 		RANGECHK(V_ipport_lowlastauto, 1, IPPORT_RESERVED - 1);
@@ -144,35 +143,35 @@ sysctl_net_ipport_check(SYSCTL_HANDLER_ARGS)
 
 SYSCTL_NODE(_net_inet_ip, IPPROTO_IP, portrange, CTLFLAG_RW, 0, "IP Ports");
 
-SYSCTL_V_PROC(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO,
-	lowfirst, CTLTYPE_INT|CTLFLAG_RW, ipport_lowfirstauto, 0,
+SYSCTL_VNET_PROC(_net_inet_ip_portrange, OID_AUTO, lowfirst,
+	CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(ipport_lowfirstauto), 0,
 	&sysctl_net_ipport_check, "I", "");
-SYSCTL_V_PROC(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO,
-	lowlast, CTLTYPE_INT|CTLFLAG_RW, ipport_lowlastauto, 0,
+SYSCTL_VNET_PROC(_net_inet_ip_portrange, OID_AUTO, lowlast,
+	CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(ipport_lowlastauto), 0,
 	&sysctl_net_ipport_check, "I", "");
-SYSCTL_V_PROC(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO,
-	first, CTLTYPE_INT|CTLFLAG_RW, ipport_firstauto, 0,
+SYSCTL_VNET_PROC(_net_inet_ip_portrange, OID_AUTO, first,
+	CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(ipport_firstauto), 0,
 	&sysctl_net_ipport_check, "I", "");
-SYSCTL_V_PROC(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO,
-	last, CTLTYPE_INT|CTLFLAG_RW, ipport_lastauto, 0,
+SYSCTL_VNET_PROC(_net_inet_ip_portrange, OID_AUTO, last,
+	CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(ipport_lastauto), 0,
 	&sysctl_net_ipport_check, "I", "");
-SYSCTL_V_PROC(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO,
-	hifirst, CTLTYPE_INT|CTLFLAG_RW, ipport_hifirstauto, 0,	
+SYSCTL_VNET_PROC(_net_inet_ip_portrange, OID_AUTO, hifirst,
+	CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(ipport_hifirstauto), 0,
 	&sysctl_net_ipport_check, "I", "");
-SYSCTL_V_PROC(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO,
-	hilast, CTLTYPE_INT|CTLFLAG_RW, ipport_hilastauto, 0,
+SYSCTL_VNET_PROC(_net_inet_ip_portrange, OID_AUTO, hilast,
+	CTLTYPE_INT|CTLFLAG_RW, &VNET_NAME(ipport_hilastauto), 0,
 	&sysctl_net_ipport_check, "I", "");
-SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO,
-	reservedhigh, CTLFLAG_RW|CTLFLAG_SECURE, ipport_reservedhigh, 0, "");
-SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO, reservedlow,
-	CTLFLAG_RW|CTLFLAG_SECURE, ipport_reservedlow, 0, "");
-SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO, randomized,
-	CTLFLAG_RW, ipport_randomized, 0, "Enable random port allocation");
-SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO, randomcps,
-	CTLFLAG_RW, ipport_randomcps, 0, "Maximum number of random port "
+SYSCTL_VNET_INT(_net_inet_ip_portrange, OID_AUTO, reservedhigh,
+	CTLFLAG_RW|CTLFLAG_SECURE, &VNET_NAME(ipport_reservedhigh), 0, "");
+SYSCTL_VNET_INT(_net_inet_ip_portrange, OID_AUTO, reservedlow,
+	CTLFLAG_RW|CTLFLAG_SECURE, &VNET_NAME(ipport_reservedlow), 0, "");
+SYSCTL_VNET_INT(_net_inet_ip_portrange, OID_AUTO, randomized, CTLFLAG_RW,
+	&VNET_NAME(ipport_randomized), 0, "Enable random port allocation");
+SYSCTL_VNET_INT(_net_inet_ip_portrange, OID_AUTO, randomcps, CTLFLAG_RW,
+	&VNET_NAME(ipport_randomcps), 0, "Maximum number of random port "
 	"allocations before switching to a sequental one");
-SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO, randomtime,
-	CTLFLAG_RW, ipport_randomtime, 0,
+SYSCTL_VNET_INT(_net_inet_ip_portrange, OID_AUTO, randomtime, CTLFLAG_RW,
+	&VNET_NAME(ipport_randomtime), 0,
 	"Minimum time to keep sequental port "
 	"allocation before switching to a random one");
 
@@ -191,9 +190,6 @@ SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip_portrange, OID_AUTO, randomtime,
 int
 in_pcballoc(struct socket *so, struct inpcbinfo *pcbinfo)
 {
-#ifdef INET6
-	INIT_VNET_INET6(curvnet);
-#endif
 	struct inpcb *inp;
 	int error;
 
@@ -288,7 +284,6 @@ int
 in_pcbbind_setup(struct inpcb *inp, struct sockaddr *nam, in_addr_t *laddrp,
     u_short *lportp, struct ucred *cred)
 {
-	INIT_VNET_INET(inp->inp_vnet);
 	struct socket *so = inp->inp_socket;
 	unsigned short *lastport;
 	struct sockaddr_in *sin;
@@ -776,7 +771,6 @@ in_pcbconnect_setup(struct inpcb *inp, struct sockaddr *nam,
     in_addr_t *laddrp, u_short *lportp, in_addr_t *faddrp, u_short *fportp,
     struct inpcb **oinpp, struct ucred *cred)
 {
-	INIT_VNET_INET(inp->inp_vnet);
 	struct sockaddr_in *sin = (struct sockaddr_in *)nam;
 	struct in_ifaddr *ia;
 	struct inpcb *oinp;
@@ -1579,7 +1573,6 @@ ipport_tick(void *xtp)
 	VNET_LIST_RLOCK();
 	VNET_FOREACH(vnet_iter) {
 		CURVNET_SET(vnet_iter);	/* XXX appease INVARIANTS here */
-		INIT_VNET_INET(vnet_iter);
 		if (V_ipport_tcpallocs <=
 		    V_ipport_tcplastcount + V_ipport_randomcps) {
 			if (V_ipport_stoprandom > 0)
@@ -1640,7 +1633,6 @@ inp_unlock_assert(struct inpcb *inp)
 void
 inp_apply_all(void (*func)(struct inpcb *, void *), void *arg)
 {
-	INIT_VNET_INET(curvnet);
 	struct inpcb *inp;
 
 	INP_INFO_RLOCK(&V_tcbinfo);