Merge the remainder of kern_vimage.c and vimage.h into vnet.c and

vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks.  Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by:	bz
Approved by:	re (vimage blanket)

1 files changed, 151 insertions, 2 deletions

diff --git a/sys/net/vnet.h b/sys/net/vnet.h
index 08ee21a..47dc7ac 100644
--- a/sys/net/vnet.h
+++ b/sys/net/vnet.h
@@ -1,4 +1,12 @@
 /*-
+ * Copyright (c) 2006-2009 University of Zagreb
+ * Copyright (c) 2006-2009 FreeBSD Foundation
+ * All rights reserved.
+ *
+ * This software was developed by the University of Zagreb and the
+ * FreeBSD Foundation under sponsorship by the Stichting NLnet and the
+ * FreeBSD Foundation.
+ *
  * Copyright (c) 2009 Jeffrey Roberson <jeff@freebsd.org>
  * Copyright (c) 2009 Robert N. M. Watson
  * All rights reserved.
@@ -31,6 +39,9 @@
  * This header file defines several sets of interfaces supporting virtualized
  * network stacks:
  *
+ * - Definition of 'struct vnet' and functions and macros to allocate/free/
+ *   manipulate it.
+ *
  * - A virtual network stack memory allocator, which provides support for
  *   virtualized global variables via a special linker set, set_vnet.
  *
@@ -47,17 +58,133 @@
 #define	_NET_VNET_H_
 
 /*
- * Virtual network stack memory allocator, which allows global variables to
- * be automatically instantiated for each network stack instance.
+ * struct vnet describes a virtualized network stack, and is primarily a
+ * pointer to storage for virtualized global variables.  Expose to userspace
+ * as required for libkvm.
  */
 #if defined(_KERNEL) || defined(_WANT_VNET)
+#include <sys/queue.h>
+
+struct vnet {
+	LIST_ENTRY(vnet)	 vnet_le;	/* all vnets list */
+	u_int			 vnet_magic_n;
+	u_int			 vnet_ifcnt;
+	u_int			 vnet_sockcnt;
+	void			*vnet_data_mem;
+	uintptr_t		 vnet_data_base;
+};
+#define	VNET_MAGIC_N	0x3e0d8f29
+
+/*
+ * These two virtual network stack allocator definitions are also required
+ * for libkvm so that it can evaluate virtualized global variables.
+ */
 #define	VNET_SETNAME		"set_vnet"
 #define	VNET_SYMPREFIX		"vnet_entry_"
 #endif
 
 #ifdef _KERNEL
+
 #ifdef VIMAGE
+#include <sys/lock.h>
+#include <sys/proc.h>			/* for struct thread */
+#include <sys/rwlock.h>
+#include <sys/sx.h>
+
+/*
+ * Functions to allocate and destroy virtual network stacks.
+ */
+struct vnet *vnet_alloc(void);
+void	vnet_destroy(struct vnet *vnet);
+
+/*
+ * The current virtual network stack -- we may wish to move this to struct
+ * pcpu in the future.
+ */
+#define	curvnet	curthread->td_vnet
+
+/*
+ * Various macros -- get and set the current network stack, but also
+ * assertions.
+ */
+#ifdef INVARIANTS
+#define	VNET_DEBUG
+#endif
+#ifdef VNET_DEBUG
+#define	VNET_ASSERT(condition)						\
+	if (!(condition)) {						\
+		printf("VNET_ASSERT @ %s:%d %s():\n",			\
+			__FILE__, __LINE__, __FUNCTION__);		\
+		panic(#condition);					\
+	}
 
+#define	CURVNET_SET_QUIET(arg)						\
+	VNET_ASSERT((arg)->vnet_magic_n == VNET_MAGIC_N);		\
+	struct vnet *saved_vnet = curvnet;				\
+	const char *saved_vnet_lpush = curthread->td_vnet_lpush;	\
+	curvnet = arg;							\
+	curthread->td_vnet_lpush = __FUNCTION__;
+ 
+#define	CURVNET_SET_VERBOSE(arg)					\
+	CURVNET_SET_QUIET(arg)						\
+	if (saved_vnet)							\
+		printf("CURVNET_SET(%p) in %s() on cpu %d, prev %p in %s()\n", \
+		       curvnet,	curthread->td_vnet_lpush, curcpu,	\
+		       saved_vnet, saved_vnet_lpush);
+
+#define	CURVNET_SET(arg)	CURVNET_SET_VERBOSE(arg)
+ 
+#define	CURVNET_RESTORE()						\
+	VNET_ASSERT(saved_vnet == NULL ||				\
+		    saved_vnet->vnet_magic_n == VNET_MAGIC_N);		\
+	curvnet = saved_vnet;						\
+	curthread->td_vnet_lpush = saved_vnet_lpush;
+#else /* !VNET_DEBUG */
+#define	VNET_ASSERT(condition)
+
+#define	CURVNET_SET(arg)						\
+	struct vnet *saved_vnet = curvnet;				\
+	curvnet = arg;	
+ 
+#define	CURVNET_SET_VERBOSE(arg)	CURVNET_SET(arg)
+#define	CURVNET_SET_QUIET(arg)		CURVNET_SET(arg)
+ 
+#define	CURVNET_RESTORE()						\
+	curvnet = saved_vnet;
+#endif /* VNET_DEBUG */
+
+extern struct vnet *vnet0;
+#define	IS_DEFAULT_VNET(arg)	((arg) == vnet0)
+
+#define	CRED_TO_VNET(cr)	(cr)->cr_prison->pr_vnet
+#define	TD_TO_VNET(td)		CRED_TO_VNET((td)->td_ucred)
+#define	P_TO_VNET(p)		CRED_TO_VNET((p)->p_ucred)
+
+/*
+ * Global linked list of all virtual network stacks, along with read locks to
+ * access it.  If a caller may sleep while accessing the list, it must use
+ * the sleepable lock macros.
+ */
+LIST_HEAD(vnet_list_head, vnet);
+extern struct vnet_list_head vnet_head;
+extern struct rwlock vnet_rwlock;
+extern struct sx vnet_sxlock;
+
+#define	VNET_LIST_RLOCK()		sx_slock(&vnet_sxlock)
+#define	VNET_LIST_RLOCK_NOSLEEP()	rw_rlock(&vnet_rwlock)
+#define	VNET_LIST_RUNLOCK()		sx_sunlock(&vnet_sxlock)
+#define	VNET_LIST_RUNLOCK_NOSLEEP()	rw_runlock(&vnet_rwlock)
+
+/*
+ * Iteration macros to walk the global list of virtual network stacks.
+ */
+#define	VNET_ITERATOR_DECL(arg)	struct vnet *arg
+#define	VNET_FOREACH(arg)	LIST_FOREACH((arg), &vnet_head, vnet_le)
+
+/*
+ * Virtual network stack memory allocator, which allows global variables to
+ * be automatically instantiated for each network stack instance.
+ */
 #if defined(__arm__)
 __asm__(".section " VNET_SETNAME ", \"aw\", %progbits");
 #else
@@ -193,6 +320,28 @@ void	vnet_deregister_sysuninit(void *arg);
 #else /* !VIMAGE */
 
 /*
+ * Various virtual network stack macros compile to no-ops without VIMAGE.
+ */
+#define	curvnet			NULL
+
+#define	VNET_ASSERT(condition)
+#define	CURVNET_SET(arg)
+#define	CURVNET_SET_QUIET(arg)
+#define	CURVNET_RESTORE()
+
+#define	VNET_LIST_RLOCK()
+#define	VNET_LIST_RLOCK_NOSLEEP()
+#define	VNET_LIST_RUNLOCK()
+#define	VNET_LIST_RUNLOCK_NOSLEEP()
+#define	VNET_ITERATOR_DECL(arg)
+#define	VNET_FOREACH(arg)
+
+#define	IS_DEFAULT_VNET(arg)	1
+#define	CRED_TO_VNET(cr)	NULL
+#define	TD_TO_VNET(td)		NULL
+#define	P_TO_VNET(p)		NULL
+
+/*
  * Versions of the VNET macros that compile to normal global variables and
  * standard sysctl definitions.
  */