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, 10 insertions, 44 deletions

diff --git a/sys/netipsec/xform_ah.c b/sys/netipsec/xform_ah.c
index 07d7001..658c92c 100644
--- a/sys/netipsec/xform_ah.c
+++ b/sys/netipsec/xform_ah.c
@@ -49,6 +49,7 @@
 #include <sys/vimage.h>
 
 #include <net/if.h>
+#include <net/vnet.h>
 
 #include <netinet/in.h>
 #include <netinet/in_systm.h>
@@ -73,17 +74,6 @@
 
 #include <opencrypto/cryptodev.h>
 
-static int ah_iattach(const void *);
-
-#ifndef VIMAGE_GLOBALS
-static const vnet_modinfo_t vnet_ah_modinfo = {
-	.vmi_id		= VNET_MOD_AH,
-	.vmi_name	= "ipsec_ah",
-	.vmi_dependson	= VNET_MOD_IPSEC,
-	.vmi_iattach	= ah_iattach
-};
-#endif /* !VIMAGE_GLOBALS */
-
 /*
  * Return header size in bytes.  The old protocol did not support
  * the replay counter; the new protocol always includes the counter.
@@ -99,19 +89,17 @@ static const vnet_modinfo_t vnet_ah_modinfo = {
 #define	AUTHSIZE(sav) \
 	((sav->flags & SADB_X_EXT_OLD) ? 16 : AH_HMAC_HASHLEN)
 
-#ifdef VIMAGE_GLOBALS
-int	ah_enable;
-int	ah_cleartos;
-struct	ahstat ahstat;
-#endif
+VNET_DEFINE(int, ah_enable) = 1;	/* control flow of packets with AH */
+VNET_DEFINE(int, ah_cleartos) = 1;	/* clear ip_tos when doing AH calc */
+VNET_DEFINE(struct ahstat, ahstat);
 
 SYSCTL_DECL(_net_inet_ah);
-SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ah, OID_AUTO,
-	ah_enable,	CTLFLAG_RW,	ah_enable,	0, "");
-SYSCTL_V_INT(V_NET, vnet_ipsec, _net_inet_ah, OID_AUTO,
-	ah_cleartos,	CTLFLAG_RW,	ah_cleartos,	0, "");
-SYSCTL_V_STRUCT(V_NET, vnet_ipsec, _net_inet_ah, IPSECCTL_STATS,
-	stats,		CTLFLAG_RD,	ahstat,	ahstat, "");
+SYSCTL_VNET_INT(_net_inet_ah, OID_AUTO,
+	ah_enable,	CTLFLAG_RW,	&VNET_NAME(ah_enable),	0, "");
+SYSCTL_VNET_INT(_net_inet_ah, OID_AUTO,
+	ah_cleartos,	CTLFLAG_RW,	&VNET_NAME(ah_cleartos), 0, "");
+SYSCTL_VNET_STRUCT(_net_inet_ah, IPSECCTL_STATS,
+	stats,		CTLFLAG_RD,	&VNET_NAME(ahstat), ahstat, "");
 
 static unsigned char ipseczeroes[256];	/* larger than an ip6 extension hdr */
 
@@ -173,7 +161,6 @@ ah_hdrsiz(struct secasvar *sav)
 int
 ah_init0(struct secasvar *sav, struct xformsw *xsp, struct cryptoini *cria)
 {
-	INIT_VNET_IPSEC(curvnet);
 	struct auth_hash *thash;
 	int keylen;
 
@@ -228,7 +215,6 @@ ah_init0(struct secasvar *sav, struct xformsw *xsp, struct cryptoini *cria)
 static int
 ah_init(struct secasvar *sav, struct xformsw *xsp)
 {
-	INIT_VNET_IPSEC(curvnet);
 	struct cryptoini cria;
 	int error;
 
@@ -263,7 +249,6 @@ ah_zeroize(struct secasvar *sav)
 static int
 ah_massage_headers(struct mbuf **m0, int proto, int skip, int alg, int out)
 {
-	INIT_VNET_IPSEC(curvnet);
 	struct mbuf *m = *m0;
 	unsigned char *ptr;
 	int off, count;
@@ -568,7 +553,6 @@ ah_massage_headers(struct mbuf **m0, int proto, int skip, int alg, int out)
 static int
 ah_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
 {
-	INIT_VNET_IPSEC(curvnet);
 	struct auth_hash *ahx;
 	struct tdb_ident *tdbi;
 	struct tdb_crypto *tc;
@@ -738,7 +722,6 @@ ah_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
 static int
 ah_input_cb(struct cryptop *crp)
 {
-	INIT_VNET_IPSEC(curvnet);
 	int rplen, error, skip, protoff;
 	unsigned char calc[AH_ALEN_MAX];
 	struct mbuf *m;
@@ -901,7 +884,6 @@ ah_output(
 	int skip,
 	int protoff)
 {
-	INIT_VNET_IPSEC(curvnet);
 	struct secasvar *sav;
 	struct auth_hash *ahx;
 	struct cryptodesc *crda;
@@ -1128,7 +1110,6 @@ bad:
 static int
 ah_output_cb(struct cryptop *crp)
 {
-	INIT_VNET_IPSEC(curvnet);
 	int skip, protoff, error;
 	struct tdb_crypto *tc;
 	struct ipsecrequest *isr;
@@ -1232,21 +1213,6 @@ ah_attach(void)
 {
 
 	xform_register(&ah_xformsw);
-#ifndef VIMAGE_GLOBALS
-	vnet_mod_register(&vnet_ah_modinfo);
-#else
-	ah_iattach(NULL);
-#endif
 }
 
-static int
-ah_iattach(const void *unused __unused)
-{
-	INIT_VNET_IPSEC(curvnet);
-
-	V_ah_enable = 1;	/* control flow of packets with AH */
-	V_ah_cleartos = 1;	/* clear ip_tos when doing AH calc */
-
-	return (0);
-}
 SYSINIT(ah_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ah_attach, NULL);