1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2006-2009 University of Zagreb
5 * Copyright (c) 2006-2009 FreeBSD Foundation
6 * All rights reserved.
7 *
8 * This software was developed by the University of Zagreb and the
9 * FreeBSD Foundation under sponsorship by the Stichting NLnet and the
10 * FreeBSD Foundation.
11 *
12 * Copyright (c) 2009 Jeffrey Roberson <jeff@freebsd.org>
13 * Copyright (c) 2009 Robert N. M. Watson
14 * All rights reserved.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 *    notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 *    notice, this list of conditions and the following disclaimer in the
23 *    documentation and/or other materials provided with the distribution.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38/*-
39 * This header file defines several sets of interfaces supporting virtualized
40 * network stacks:
41 *
42 * - Definition of 'struct vnet' and functions and macros to allocate/free/
43 *   manipulate it.
44 *
45 * - A virtual network stack memory allocator, which provides support for
46 *   virtualized global variables via a special linker set, set_vnet.
47 *
48 * - Virtualized sysinits/sysuninits, which allow constructors and
49 *   destructors to be run for each network stack subsystem as virtual
50 *   instances are created and destroyed.
51 *
52 * If VIMAGE isn't compiled into the kernel, virtualized global variables
53 * compile to normal global variables, and virtualized sysinits to regular
54 * sysinits.
55 */
56
57#ifndef _NET_VNET_H_
58#define	_NET_VNET_H_
59
60/*
61 * struct vnet describes a virtualized network stack, and is primarily a
62 * pointer to storage for virtualized global variables.  Expose to userspace
63 * as required for libkvm.
64 */
65#if defined(_KERNEL) || defined(_WANT_VNET)
66#include <machine/param.h>	/* for CACHE_LINE_SIZE */
67#include <sys/queue.h>
68
69struct vnet {
70	LIST_ENTRY(vnet)	 vnet_le;	/* all vnets list */
71	u_int			 vnet_magic_n;
72	u_int			 vnet_ifcnt;
73	u_int			 vnet_sockcnt;
74	u_int			 vnet_state;	/* SI_SUB_* */
75	void			*vnet_data_mem;
76	uintptr_t		 vnet_data_base;
77	bool			 vnet_shutdown;	/* Shutdown in progress. */
78} __aligned(CACHE_LINE_SIZE);
79#define	VNET_MAGIC_N	0x5e4a6f28
80
81/*
82 * These two virtual network stack allocator definitions are also required
83 * for libkvm so that it can evaluate virtualized global variables.
84 */
85#define	VNET_SETNAME		"set_vnet"
86#define	VNET_SYMPREFIX		"vnet_entry_"
87#endif
88
89#ifdef _KERNEL
90
91#define	VNET_PCPUSTAT_DECLARE(type, name)	\
92    VNET_DECLARE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
93
94#define	VNET_PCPUSTAT_DEFINE(type, name)	\
95    VNET_DEFINE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
96#define	VNET_PCPUSTAT_DEFINE_STATIC(type, name)	\
97    VNET_DEFINE_STATIC(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
98
99#define	VNET_PCPUSTAT_ALLOC(name, wait)	\
100    COUNTER_ARRAY_ALLOC(VNET(name), \
101	sizeof(VNET(name)) / sizeof(counter_u64_t), (wait))
102
103#define	VNET_PCPUSTAT_FREE(name)	\
104    COUNTER_ARRAY_FREE(VNET(name), sizeof(VNET(name)) / sizeof(counter_u64_t))
105
106#define	VNET_PCPUSTAT_ADD(type, name, f, v)	\
107    counter_u64_add(VNET(name)[offsetof(type, f) / sizeof(uint64_t)], (v))
108
109#define	VNET_PCPUSTAT_FETCH(type, name, f)	\
110    counter_u64_fetch(VNET(name)[offsetof(type, f) / sizeof(uint64_t)])
111
112#define	VNET_PCPUSTAT_SYSINIT(name)	\
113static void				\
114vnet_##name##_init(const void *unused)	\
115{					\
116	VNET_PCPUSTAT_ALLOC(name, M_WAITOK);	\
117}					\
118VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_INIT_IF,			\
119    SI_ORDER_FIRST, vnet_ ## name ## _init, NULL)
120
121#define	VNET_PCPUSTAT_SYSUNINIT(name)					\
122static void								\
123vnet_##name##_uninit(const void *unused)				\
124{									\
125	VNET_PCPUSTAT_FREE(name);					\
126}									\
127VNET_SYSUNINIT(vnet_ ## name ## _uninit, SI_SUB_INIT_IF,		\
128    SI_ORDER_FIRST, vnet_ ## name ## _uninit, NULL)
129
130#ifdef SYSCTL_OID
131#define	SYSCTL_VNET_PCPUSTAT(parent, nbr, name, type, array, desc)	\
132static int								\
133array##_sysctl(SYSCTL_HANDLER_ARGS)					\
134{									\
135	type s;								\
136	CTASSERT((sizeof(type) / sizeof(uint64_t)) ==			\
137	    (sizeof(VNET(array)) / sizeof(counter_u64_t)));		\
138	COUNTER_ARRAY_COPY(VNET(array), &s, sizeof(type) / sizeof(uint64_t));\
139	if (req->newptr)						\
140		COUNTER_ARRAY_ZERO(VNET(array),				\
141		    sizeof(type) / sizeof(uint64_t));			\
142	return (SYSCTL_OUT(req, &s, sizeof(type)));			\
143}									\
144SYSCTL_PROC(parent, nbr, name,						\
145    CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_NEEDGIANT,	\
146    NULL, 0, array ## _sysctl, "I", desc)
147#endif /* SYSCTL_OID */
148
149#ifdef VIMAGE
150#include <sys/lock.h>
151#include <sys/proc.h>			/* for struct thread */
152#include <sys/rwlock.h>
153#include <sys/sx.h>
154
155/*
156 * Location of the kernel's 'set_vnet' linker set.
157 */
158extern uintptr_t	*__start_set_vnet;
159__GLOBL(__start_set_vnet);
160extern uintptr_t	*__stop_set_vnet;
161__GLOBL(__stop_set_vnet);
162
163#define	VNET_START	(uintptr_t)&__start_set_vnet
164#define	VNET_STOP	(uintptr_t)&__stop_set_vnet
165
166/*
167 * Functions to allocate and destroy virtual network stacks.
168 */
169struct vnet *vnet_alloc(void);
170void	vnet_destroy(struct vnet *vnet);
171
172/*
173 * The current virtual network stack -- we may wish to move this to struct
174 * pcpu in the future.
175 */
176#define	curvnet	curthread->td_vnet
177
178/*
179 * Various macros -- get and set the current network stack, but also
180 * assertions.
181 */
182#if defined(INVARIANTS) || defined(VNET_DEBUG)
183#define	VNET_ASSERT(exp, msg)	do {					\
184	if (!(exp))							\
185		panic msg;						\
186} while (0)
187#else
188#define	VNET_ASSERT(exp, msg)	do {					\
189} while (0)
190#endif
191
192#ifdef VNET_DEBUG
193void vnet_log_recursion(struct vnet *, const char *, int);
194
195#define	CURVNET_SET_QUIET(arg)						\
196	VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
197	    ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",		\
198	    __FILE__, __LINE__, __func__, curvnet, (arg)));		\
199	struct vnet *saved_vnet = curvnet;				\
200	const char *saved_vnet_lpush = curthread->td_vnet_lpush;	\
201	curvnet = arg;							\
202	curthread->td_vnet_lpush = __func__;
203
204#define	CURVNET_SET_VERBOSE(arg)					\
205	CURVNET_SET_QUIET(arg)						\
206	if (saved_vnet)							\
207		vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
208
209#define	CURVNET_SET(arg)	CURVNET_SET_VERBOSE(arg)
210
211#define	CURVNET_RESTORE()						\
212	VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||		\
213	    saved_vnet->vnet_magic_n == VNET_MAGIC_N),			\
214	    ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",	\
215	    __FILE__, __LINE__, __func__, curvnet, saved_vnet));	\
216	curvnet = saved_vnet;						\
217	curthread->td_vnet_lpush = saved_vnet_lpush;
218#else /* !VNET_DEBUG */
219
220#define	CURVNET_SET_QUIET(arg)						\
221	VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
222	    ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",		\
223	    __FILE__, __LINE__, __func__, curvnet, (arg)));		\
224	struct vnet *saved_vnet = curvnet;				\
225	curvnet = arg;
226
227#define	CURVNET_SET_VERBOSE(arg)					\
228	CURVNET_SET_QUIET(arg)
229
230#define	CURVNET_SET(arg)	CURVNET_SET_VERBOSE(arg)
231
232#define	CURVNET_RESTORE()						\
233	VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||		\
234	    saved_vnet->vnet_magic_n == VNET_MAGIC_N),			\
235	    ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",	\
236	    __FILE__, __LINE__, __func__, curvnet, saved_vnet));	\
237	curvnet = saved_vnet;
238#endif /* VNET_DEBUG */
239
240#define	CURVNET_ASSERT_SET()						\
241	VNET_ASSERT(curvnet != NULL, ("vnet is not set at %s:%d %s()",  \
242	    __FILE__, __LINE__, __func__))
243
244extern struct vnet *vnet0;
245#define	IS_DEFAULT_VNET(arg)	((arg) == vnet0)
246
247#define	CRED_TO_VNET(cr)	(cr)->cr_prison->pr_vnet
248#define	TD_TO_VNET(td)		CRED_TO_VNET((td)->td_ucred)
249#define	P_TO_VNET(p)		CRED_TO_VNET((p)->p_ucred)
250
251/*
252 * Global linked list of all virtual network stacks, along with read locks to
253 * access it.  If a caller may sleep while accessing the list, it must use
254 * the sleepable lock macros.
255 */
256LIST_HEAD(vnet_list_head, vnet);
257extern struct vnet_list_head vnet_head;
258extern struct rwlock vnet_rwlock;
259extern struct sx vnet_sxlock;
260
261#define	VNET_LIST_RLOCK()		sx_slock(&vnet_sxlock)
262#define	VNET_LIST_RLOCK_NOSLEEP()	rw_rlock(&vnet_rwlock)
263#define	VNET_LIST_RUNLOCK()		sx_sunlock(&vnet_sxlock)
264#define	VNET_LIST_RUNLOCK_NOSLEEP()	rw_runlock(&vnet_rwlock)
265
266/*
267 * Iteration macros to walk the global list of virtual network stacks.
268 */
269#define	VNET_ITERATOR_DECL(arg)	struct vnet *arg
270#define	VNET_FOREACH(arg)	LIST_FOREACH((arg), &vnet_head, vnet_le)
271
272/*
273 * Virtual network stack memory allocator, which allows global variables to
274 * be automatically instantiated for each network stack instance.
275 */
276#define	VNET_NAME(n)		vnet_entry_##n
277#define	VNET_DECLARE(t, n)	extern t VNET_NAME(n)
278/* struct _hack is to stop this from being used with static data */
279#define	VNET_DEFINE(t, n)	\
280    struct _hack; t VNET_NAME(n) __section(VNET_SETNAME) __used
281#if defined(KLD_MODULE) && (defined(__aarch64__) || defined(__riscv) \
282		|| defined(__powerpc64__) || defined(__i386__))
283/*
284 * As with DPCPU_DEFINE_STATIC we are unable to mark this data as static
285 * in modules on some architectures.
286 */
287#define	VNET_DEFINE_STATIC(t, n) \
288    t VNET_NAME(n) __section(VNET_SETNAME) __used
289#else
290#define	VNET_DEFINE_STATIC(t, n) \
291    static t VNET_NAME(n) __section(VNET_SETNAME) __used
292#endif
293#define	_VNET_PTR(b, n)		(__typeof(VNET_NAME(n))*)		\
294				    ((b) + (uintptr_t)&VNET_NAME(n))
295
296#define	_VNET(b, n)		(*_VNET_PTR(b, n))
297
298/*
299 * Virtualized global variable accessor macros.
300 */
301#define	VNET_VNET_PTR(vnet, n)		_VNET_PTR((vnet)->vnet_data_base, n)
302#define	VNET_VNET(vnet, n)		(*VNET_VNET_PTR((vnet), n))
303
304#define	VNET_PTR(n)		VNET_VNET_PTR(curvnet, n)
305#define	VNET(n)			VNET_VNET(curvnet, n)
306
307/*
308 * Virtual network stack allocator interfaces from the kernel linker.
309 */
310void	*vnet_data_alloc(int size);
311void	 vnet_data_copy(void *start, int size);
312void	 vnet_data_free(void *start_arg, int size);
313
314/*
315 * Interfaces to manipulate the initial values of virtualized global variables.
316 */
317void    vnet_save_init(void *, size_t);
318void    vnet_restore_init(void *, size_t);
319
320/*
321 * Virtual sysinit mechanism, allowing network stack components to declare
322 * startup and shutdown methods to be run when virtual network stack
323 * instances are created and destroyed.
324 */
325#include <sys/kernel.h>
326
327/*
328 * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
329 * destructors.
330 */
331struct vnet_sysinit {
332	enum sysinit_sub_id	subsystem;
333	enum sysinit_elem_order	order;
334	sysinit_cfunc_t		func;
335	const void		*arg;
336	TAILQ_ENTRY(vnet_sysinit) link;
337};
338
339#define	VNET_SYSINIT(ident, subsystem, order, func, arg)		\
340	CTASSERT((subsystem) > SI_SUB_VNET &&				\
341	    (subsystem) <= SI_SUB_VNET_DONE);				\
342	static struct vnet_sysinit ident ## _vnet_init = {		\
343		subsystem,						\
344		order,							\
345		(sysinit_cfunc_t)(sysinit_nfunc_t)func,			\
346		(arg)							\
347	};								\
348	SYSINIT(vnet_init_ ## ident, subsystem, order,			\
349	    vnet_register_sysinit, &ident ## _vnet_init);		\
350	SYSUNINIT(vnet_init_ ## ident, subsystem, order,		\
351	    vnet_deregister_sysinit, &ident ## _vnet_init)
352
353#define	VNET_SYSUNINIT(ident, subsystem, order, func, arg)		\
354	CTASSERT((subsystem) > SI_SUB_VNET &&				\
355	    (subsystem) <= SI_SUB_VNET_DONE);				\
356	static struct vnet_sysinit ident ## _vnet_uninit = {		\
357		subsystem,						\
358		order,							\
359		(sysinit_cfunc_t)(sysinit_nfunc_t)func,			\
360		(arg)							\
361	};								\
362	SYSINIT(vnet_uninit_ ## ident, subsystem, order,		\
363	    vnet_register_sysuninit, &ident ## _vnet_uninit);		\
364	SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,		\
365	    vnet_deregister_sysuninit, &ident ## _vnet_uninit)
366
367/*
368 * Interfaces for managing per-vnet constructors and destructors.
369 */
370void	vnet_register_sysinit(void *arg);
371void	vnet_register_sysuninit(void *arg);
372void	vnet_deregister_sysinit(void *arg);
373void	vnet_deregister_sysuninit(void *arg);
374
375/*
376 * EVENTHANDLER(9) extensions.
377 */
378#include <sys/eventhandler.h>
379
380void	vnet_global_eventhandler_iterator_func(void *, ...);
381#define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
382do {									\
383	if (IS_DEFAULT_VNET(curvnet)) {					\
384		(tag) = vimage_eventhandler_register(NULL, #name, func,	\
385		    arg, priority,					\
386		    vnet_global_eventhandler_iterator_func);		\
387	}								\
388} while(0)
389#define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)	\
390do {									\
391	if (IS_DEFAULT_VNET(curvnet)) {					\
392		vimage_eventhandler_register(NULL, #name, func,		\
393		    arg, priority,					\
394		    vnet_global_eventhandler_iterator_func);		\
395	}								\
396} while(0)
397
398#else /* !VIMAGE */
399
400/*
401 * Various virtual network stack macros compile to no-ops without VIMAGE.
402 */
403#define	curvnet			NULL
404
405#define	VNET_ASSERT(exp, msg)
406#define	CURVNET_SET(arg)
407#define	CURVNET_SET_QUIET(arg)
408#define	CURVNET_RESTORE()
409#define	CURVNET_ASSERT_SET()
410
411#define	VNET_LIST_RLOCK()
412#define	VNET_LIST_RLOCK_NOSLEEP()
413#define	VNET_LIST_RUNLOCK()
414#define	VNET_LIST_RUNLOCK_NOSLEEP()
415#define	VNET_ITERATOR_DECL(arg)
416#define	VNET_FOREACH(arg)	for (int _vn = 0; _vn == 0; _vn++)
417
418#define	IS_DEFAULT_VNET(arg)	1
419#define	CRED_TO_VNET(cr)	NULL
420#define	TD_TO_VNET(td)		NULL
421#define	P_TO_VNET(p)		NULL
422
423/*
424 * Versions of the VNET macros that compile to normal global variables and
425 * standard sysctl definitions.
426 */
427#define	VNET_NAME(n)		n
428#define	VNET_DECLARE(t, n)	extern t n
429#define	VNET_DEFINE(t, n)	struct _hack; t n
430#define	VNET_DEFINE_STATIC(t, n)	static t n
431#define	_VNET_PTR(b, n)		&VNET_NAME(n)
432
433/*
434 * Virtualized global variable accessor macros.
435 */
436#define	VNET_VNET_PTR(vnet, n)		(&(n))
437#define	VNET_VNET(vnet, n)		(n)
438
439#define	VNET_PTR(n)		(&(n))
440#define	VNET(n)			(n)
441
442/*
443 * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
444 * map into normal sysinits, which have the same ordering properties.
445 */
446#define	VNET_SYSINIT(ident, subsystem, order, func, arg)		\
447	SYSINIT(ident, subsystem, order, func, arg)
448#define	VNET_SYSUNINIT(ident, subsystem, order, func, arg)		\
449	SYSUNINIT(ident, subsystem, order, func, arg)
450
451/*
452 * Without VIMAGE revert to the default implementation.
453 */
454#define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
455	(tag) = eventhandler_register(NULL, #name, func, arg, priority)
456#define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)	\
457	eventhandler_register(NULL, #name, func, arg, priority)
458#endif /* VIMAGE */
459#endif /* _KERNEL */
460
461#endif /* !_NET_VNET_H_ */
462