freebsd-skq/sys/net/vnet.h
Bjoern A. Zeeb 42eedeac00 Split eventhandler_register() into an internal part and a wrapper function
that provides the allocated and setup eventhandler entry.

Add a new wrapper for VIMAGE that allocates extra space to hold the
callback function and argument in addition to an extra wrapper function.
While the wrapper function goes as normal callback function the
argument points to the extra space allocated holding the original func
and arg that the wrapper function can then call.

Provide an iterator function for the virtual network stack (vnet) that
will call the callback function for each network stack.

Provide a new set of macros for VNET that in the non-VIMAGE case will
just call eventhandler_register() while in the VIMAGE case it will use
vimage_eventhandler_register() passing in the extra iterator function
but will only register once rather than per-vnet.
We need a special macro in case we are interested in the tag returned
as we must check for curvnet and can neither simply assign the
return value, nor not change it in the non-vnet0 case without that.

Sponsored by:	ISPsystem
Discussed with:	jhb
Reviewed by:	zec (earlier version), jhb
MFC after:	1 month
2010-03-19 19:51:03 +00:00

421 lines
14 KiB
C

/*-
* 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.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*-
* 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.
*
* - Virtualized sysinits/sysuninits, which allow constructors and
* destructors to be run for each network stack subsystem as virtual
* instances are created and destroyed.
*
* If VIMAGE isn't compiled into the kernel, virtualized global variables
* compile to normal global variables, and virtualized sysinits to regular
* sysinits.
*/
#ifndef _NET_VNET_H_
#define _NET_VNET_H_
/*
* 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 VNET_DEBUG
void vnet_log_recursion(struct vnet *, const char *, int);
#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) \
vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
#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.
*/
__asm__(
#if defined(__arm__)
".section " VNET_SETNAME ", \"aw\", %progbits\n"
#else
".section " VNET_SETNAME ", \"aw\", @progbits\n"
#endif
"\t.p2align " __XSTRING(CACHE_LINE_SHIFT) "\n"
"\t.previous");
#define VNET_NAME(n) vnet_entry_##n
#define VNET_DECLARE(t, n) extern t VNET_NAME(n)
#define VNET_DEFINE(t, n) t VNET_NAME(n) __section(VNET_SETNAME) __used
#define _VNET_PTR(b, n) (__typeof(VNET_NAME(n))*) \
((b) + (uintptr_t)&VNET_NAME(n))
#define _VNET(b, n) (*_VNET_PTR(b, n))
/*
* Virtualized global variable accessor macros.
*/
#define VNET_VNET_PTR(vnet, n) _VNET_PTR((vnet)->vnet_data_base, n)
#define VNET_VNET(vnet, n) (*VNET_VNET_PTR((vnet), n))
#define VNET_PTR(n) VNET_VNET_PTR(curvnet, n)
#define VNET(n) VNET_VNET(curvnet, n)
/*
* Virtual network stack allocator interfaces from the kernel linker.
*/
void *vnet_data_alloc(int size);
void vnet_data_copy(void *start, int size);
void vnet_data_free(void *start_arg, int size);
/*
* Sysctl variants for vnet-virtualized global variables. Include
* <sys/sysctl.h> to expose these definitions.
*
* Note: SYSCTL_PROC() handler functions will need to resolve pointer
* arguments themselves, if required.
*/
#ifdef SYSCTL_OID
int vnet_sysctl_handle_int(SYSCTL_HANDLER_ARGS);
int vnet_sysctl_handle_opaque(SYSCTL_HANDLER_ARGS);
int vnet_sysctl_handle_string(SYSCTL_HANDLER_ARGS);
int vnet_sysctl_handle_uint(SYSCTL_HANDLER_ARGS);
#define SYSCTL_VNET_INT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_INT|CTLFLAG_MPSAFE|CTLFLAG_VNET|(access), \
ptr, val, vnet_sysctl_handle_int, "I", descr)
#define SYSCTL_VNET_PROC(parent, nbr, name, access, ptr, arg, handler, \
fmt, descr) \
SYSCTL_OID(parent, nbr, name, CTLFLAG_VNET|(access), ptr, arg, \
handler, fmt, descr)
#define SYSCTL_VNET_STRING(parent, nbr, name, access, arg, len, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_STRING|CTLFLAG_VNET|(access), \
arg, len, vnet_sysctl_handle_string, "A", descr)
#define SYSCTL_VNET_STRUCT(parent, nbr, name, access, ptr, type, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_OPAQUE|CTLFLAG_VNET|(access), ptr, \
sizeof(struct type), vnet_sysctl_handle_opaque, "S," #type, \
descr)
#define SYSCTL_VNET_UINT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_UINT|CTLFLAG_MPSAFE|CTLFLAG_VNET|(access), \
ptr, val, vnet_sysctl_handle_uint, "IU", descr)
#define VNET_SYSCTL_ARG(req, arg1) do { \
if (arg1 != NULL) \
arg1 = (void *)(TD_TO_VNET((req)->td)->vnet_data_base + \
(uintptr_t)(arg1)); \
} while (0)
#endif /* SYSCTL_OID */
/*
* Virtual sysinit mechanism, allowing network stack components to declare
* startup and shutdown methods to be run when virtual network stack
* instances are created and destroyed.
*/
#include <sys/kernel.h>
/*
* SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
* destructors.
*/
struct vnet_sysinit {
enum sysinit_sub_id subsystem;
enum sysinit_elem_order order;
sysinit_cfunc_t func;
const void *arg;
TAILQ_ENTRY(vnet_sysinit) link;
};
#define VNET_SYSINIT(ident, subsystem, order, func, arg) \
static struct vnet_sysinit ident ## _vnet_init = { \
subsystem, \
order, \
(sysinit_cfunc_t)(sysinit_nfunc_t)func, \
(arg) \
}; \
SYSINIT(vnet_init_ ## ident, subsystem, order, \
vnet_register_sysinit, &ident ## _vnet_init); \
SYSUNINIT(vnet_init_ ## ident, subsystem, order, \
vnet_deregister_sysinit, &ident ## _vnet_init)
#define VNET_SYSUNINIT(ident, subsystem, order, func, arg) \
static struct vnet_sysinit ident ## _vnet_uninit = { \
subsystem, \
order, \
(sysinit_cfunc_t)(sysinit_nfunc_t)func, \
(arg) \
}; \
SYSINIT(vnet_uninit_ ## ident, subsystem, order, \
vnet_register_sysuninit, &ident ## _vnet_uninit); \
SYSUNINIT(vnet_uninit_ ## ident, subsystem, order, \
vnet_deregister_sysuninit, &ident ## _vnet_uninit)
/*
* Run per-vnet sysinits or sysuninits during vnet creation/destruction.
*/
void vnet_sysinit(void);
void vnet_sysuninit(void);
/*
* Interfaces for managing per-vnet constructors and destructors.
*/
void vnet_register_sysinit(void *arg);
void vnet_register_sysuninit(void *arg);
void vnet_deregister_sysinit(void *arg);
void vnet_deregister_sysuninit(void *arg);
/*
* EVENTHANDLER(9) extensions.
*/
#include <sys/eventhandler.h>
void vnet_global_eventhandler_iterator_func(void *, ...);
#define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
do { \
if (IS_DEFAULT_VNET(curvnet)) { \
(tag) = vimage_eventhandler_register(NULL, #name, func, \
arg, priority, \
vnet_global_eventhandler_iterator_func); \
} \
} while(0)
#define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority) \
do { \
if (IS_DEFAULT_VNET(curvnet)) { \
vimage_eventhandler_register(NULL, #name, func, \
arg, priority, \
vnet_global_eventhandler_iterator_func); \
} \
} while(0)
#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.
*/
#define VNET_NAME(n) n
#define VNET_DECLARE(t, n) extern t n
#define VNET_DEFINE(t, n) t n
#define _VNET_PTR(b, n) &VNET_NAME(n)
/*
* Virtualized global variable accessor macros.
*/
#define VNET_VNET_PTR(vnet, n) (&(n))
#define VNET_VNET(vnet, n) (n)
#define VNET_PTR(n) (&(n))
#define VNET(n) (n)
/*
* When VIMAGE isn't compiled into the kernel, virtaulized SYSCTLs simply
* become normal SYSCTLs.
*/
#ifdef SYSCTL_OID
#define SYSCTL_VNET_INT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_INT(parent, nbr, name, access, ptr, val, descr)
#define SYSCTL_VNET_PROC(parent, nbr, name, access, ptr, arg, handler, \
fmt, descr) \
SYSCTL_PROC(parent, nbr, name, access, ptr, arg, handler, fmt, \
descr)
#define SYSCTL_VNET_STRING(parent, nbr, name, access, arg, len, descr) \
SYSCTL_STRING(parent, nbr, name, access, arg, len, descr)
#define SYSCTL_VNET_STRUCT(parent, nbr, name, access, ptr, type, descr) \
SYSCTL_STRUCT(parent, nbr, name, access, ptr, type, descr)
#define SYSCTL_VNET_UINT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_UINT(parent, nbr, name, access, ptr, val, descr)
#define VNET_SYSCTL_ARG(req, arg1)
#endif /* SYSCTL_OID */
/*
* When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
* map into normal sysinits, which have the same ordering properties.
*/
#define VNET_SYSINIT(ident, subsystem, order, func, arg) \
SYSINIT(ident, subsystem, order, func, arg)
#define VNET_SYSUNINIT(ident, subsystem, order, func, arg) \
SYSUNINIT(ident, subsystem, order, func, arg)
/*
* Without VIMAGE revert to the default implementation.
*/
#define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
(tag) = eventhandler_register(NULL, #name, func, arg, priority)
#define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority) \
eventhandler_register(NULL, #name, func, arg, priority)
#endif /* VIMAGE */
#endif /* _KERNEL */
#endif /* !_NET_VNET_H_ */