xref: /freebsd/sys/net/vnet.h (revision 27c43fe1f3795622c5bd4bbfc465a29a800c0799)
1 /*-
2  * Copyright (c) 2006-2009 University of Zagreb
3  * Copyright (c) 2006-2009 FreeBSD Foundation
4  * All rights reserved.
5  *
6  * This software was developed by the University of Zagreb and the
7  * FreeBSD Foundation under sponsorship by the Stichting NLnet and the
8  * FreeBSD Foundation.
9  *
10  * Copyright (c) 2009 Jeffrey Roberson <jeff@freebsd.org>
11  * Copyright (c) 2009 Robert N. M. Watson
12  * All rights reserved.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $FreeBSD$
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 <sys/queue.h>
67 
68 struct vnet {
69 	LIST_ENTRY(vnet)	 vnet_le;	/* all vnets list */
70 	u_int			 vnet_magic_n;
71 	u_int			 vnet_ifcnt;
72 	u_int			 vnet_sockcnt;
73 	void			*vnet_data_mem;
74 	uintptr_t		 vnet_data_base;
75 };
76 #define	VNET_MAGIC_N	0x3e0d8f29
77 
78 /*
79  * These two virtual network stack allocator definitions are also required
80  * for libkvm so that it can evaluate virtualized global variables.
81  */
82 #define	VNET_SETNAME		"set_vnet"
83 #define	VNET_SYMPREFIX		"vnet_entry_"
84 #endif
85 
86 #ifdef _KERNEL
87 
88 #define	VNET_PCPUSTAT_DECLARE(type, name)	\
89     VNET_DECLARE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
90 
91 #define	VNET_PCPUSTAT_DEFINE(type, name)	\
92     VNET_DEFINE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
93 
94 #define	VNET_PCPUSTAT_ALLOC(name, wait)	\
95     COUNTER_ARRAY_ALLOC(VNET(name), \
96 	sizeof(VNET(name)) / sizeof(counter_u64_t), (wait))
97 
98 #define	VNET_PCPUSTAT_FREE(name)	\
99     COUNTER_ARRAY_FREE(VNET(name), sizeof(VNET(name)) / sizeof(counter_u64_t))
100 
101 #define	VNET_PCPUSTAT_ADD(type, name, f, v)	\
102     counter_u64_add(VNET(name)[offsetof(type, f) / sizeof(uint64_t)], (v))
103 
104 #define	VNET_PCPUSTAT_SYSINIT(name)	\
105 static void				\
106 vnet_##name##_init(const void *unused)	\
107 {					\
108 	VNET_PCPUSTAT_ALLOC(name, M_WAITOK);	\
109 }					\
110 VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_PROTO_IFATTACHDOMAIN,	\
111     SI_ORDER_ANY, vnet_ ## name ## _init, NULL)
112 
113 #define	VNET_PCPUSTAT_SYSUNINIT(name)					\
114 static void								\
115 vnet_##name##_uninit(const void *unused)				\
116 {									\
117 	VNET_PCPUSTAT_FREE(name);					\
118 }									\
119 VNET_SYSUNINIT(vnet_ ## name ## _uninit, SI_SUB_PROTO_IFATTACHDOMAIN,	\
120     SI_ORDER_ANY, vnet_ ## name ## _uninit, NULL)
121 
122 #define	SYSCTL_VNET_PCPUSTAT(parent, nbr, name, type, array, desc)	\
123 static int								\
124 array##_sysctl(SYSCTL_HANDLER_ARGS)					\
125 {									\
126 	type s;								\
127 	CTASSERT((sizeof(type) / sizeof(uint64_t)) ==			\
128 	    (sizeof(VNET(array)) / sizeof(counter_u64_t)));		\
129 	COUNTER_ARRAY_COPY(VNET(array), &s, sizeof(type) / sizeof(uint64_t));\
130 	if (req->newptr)						\
131 		COUNTER_ARRAY_ZERO(VNET(array),				\
132 		    sizeof(type) / sizeof(uint64_t));			\
133 	return (SYSCTL_OUT(req, &s, sizeof(type)));			\
134 }									\
135 SYSCTL_VNET_PROC(parent, nbr, name, CTLTYPE_OPAQUE | CTLFLAG_RW, NULL,	\
136     0, array ## _sysctl, "I", desc)
137 
138 #ifdef VIMAGE
139 #include <sys/lock.h>
140 #include <sys/proc.h>			/* for struct thread */
141 #include <sys/rwlock.h>
142 #include <sys/sx.h>
143 
144 /*
145  * Location of the kernel's 'set_vnet' linker set.
146  */
147 extern uintptr_t	*__start_set_vnet;
148 __GLOBL(__start_set_vnet);
149 extern uintptr_t	*__stop_set_vnet;
150 __GLOBL(__stop_set_vnet);
151 
152 #define	VNET_START	(uintptr_t)&__start_set_vnet
153 #define	VNET_STOP	(uintptr_t)&__stop_set_vnet
154 
155 /*
156  * Functions to allocate and destroy virtual network stacks.
157  */
158 struct vnet *vnet_alloc(void);
159 void	vnet_destroy(struct vnet *vnet);
160 
161 /*
162  * The current virtual network stack -- we may wish to move this to struct
163  * pcpu in the future.
164  */
165 #define	curvnet	curthread->td_vnet
166 
167 /*
168  * Various macros -- get and set the current network stack, but also
169  * assertions.
170  */
171 #if defined(INVARIANTS) || defined(VNET_DEBUG)
172 #define	VNET_ASSERT(exp, msg)	do {					\
173 	if (!(exp))							\
174 		panic msg;						\
175 } while (0)
176 #else
177 #define	VNET_ASSERT(exp, msg)	do {					\
178 } while (0)
179 #endif
180 
181 #ifdef VNET_DEBUG
182 void vnet_log_recursion(struct vnet *, const char *, int);
183 
184 #define	CURVNET_SET_QUIET(arg)						\
185 	VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
186 	    ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",		\
187 	    __FILE__, __LINE__, __func__, curvnet, (arg)));		\
188 	struct vnet *saved_vnet = curvnet;				\
189 	const char *saved_vnet_lpush = curthread->td_vnet_lpush;	\
190 	curvnet = arg;							\
191 	curthread->td_vnet_lpush = __func__;
192 
193 #define	CURVNET_SET_VERBOSE(arg)					\
194 	CURVNET_SET_QUIET(arg)						\
195 	if (saved_vnet)							\
196 		vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
197 
198 #define	CURVNET_SET(arg)	CURVNET_SET_VERBOSE(arg)
199 
200 #define	CURVNET_RESTORE()						\
201 	VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||		\
202 	    saved_vnet->vnet_magic_n == VNET_MAGIC_N),			\
203 	    ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",	\
204 	    __FILE__, __LINE__, __func__, curvnet, saved_vnet));	\
205 	curvnet = saved_vnet;						\
206 	curthread->td_vnet_lpush = saved_vnet_lpush;
207 #else /* !VNET_DEBUG */
208 
209 #define	CURVNET_SET_QUIET(arg)						\
210 	VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
211 	    ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",		\
212 	    __FILE__, __LINE__, __func__, curvnet, (arg)));		\
213 	struct vnet *saved_vnet = curvnet;				\
214 	curvnet = arg;
215 
216 #define	CURVNET_SET_VERBOSE(arg)					\
217 	CURVNET_SET_QUIET(arg)
218 
219 #define	CURVNET_SET(arg)	CURVNET_SET_VERBOSE(arg)
220 
221 #define	CURVNET_RESTORE()						\
222 	VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||		\
223 	    saved_vnet->vnet_magic_n == VNET_MAGIC_N),			\
224 	    ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",	\
225 	    __FILE__, __LINE__, __func__, curvnet, saved_vnet));	\
226 	curvnet = saved_vnet;
227 #endif /* VNET_DEBUG */
228 
229 extern struct vnet *vnet0;
230 #define	IS_DEFAULT_VNET(arg)	((arg) == vnet0)
231 
232 #define	CRED_TO_VNET(cr)	(cr)->cr_prison->pr_vnet
233 #define	TD_TO_VNET(td)		CRED_TO_VNET((td)->td_ucred)
234 #define	P_TO_VNET(p)		CRED_TO_VNET((p)->p_ucred)
235 
236 /*
237  * Global linked list of all virtual network stacks, along with read locks to
238  * access it.  If a caller may sleep while accessing the list, it must use
239  * the sleepable lock macros.
240  */
241 LIST_HEAD(vnet_list_head, vnet);
242 extern struct vnet_list_head vnet_head;
243 extern struct rwlock vnet_rwlock;
244 extern struct sx vnet_sxlock;
245 
246 #define	VNET_LIST_RLOCK()		sx_slock(&vnet_sxlock)
247 #define	VNET_LIST_RLOCK_NOSLEEP()	rw_rlock(&vnet_rwlock)
248 #define	VNET_LIST_RUNLOCK()		sx_sunlock(&vnet_sxlock)
249 #define	VNET_LIST_RUNLOCK_NOSLEEP()	rw_runlock(&vnet_rwlock)
250 
251 /*
252  * Iteration macros to walk the global list of virtual network stacks.
253  */
254 #define	VNET_ITERATOR_DECL(arg)	struct vnet *arg
255 #define	VNET_FOREACH(arg)	LIST_FOREACH((arg), &vnet_head, vnet_le)
256 
257 /*
258  * Virtual network stack memory allocator, which allows global variables to
259  * be automatically instantiated for each network stack instance.
260  */
261 #define	VNET_NAME(n)		vnet_entry_##n
262 #define	VNET_DECLARE(t, n)	extern t VNET_NAME(n)
263 #define	VNET_DEFINE(t, n)	t VNET_NAME(n) __section(VNET_SETNAME) __used
264 #define	_VNET_PTR(b, n)		(__typeof(VNET_NAME(n))*)		\
265 				    ((b) + (uintptr_t)&VNET_NAME(n))
266 
267 #define	_VNET(b, n)		(*_VNET_PTR(b, n))
268 
269 /*
270  * Virtualized global variable accessor macros.
271  */
272 #define	VNET_VNET_PTR(vnet, n)		_VNET_PTR((vnet)->vnet_data_base, n)
273 #define	VNET_VNET(vnet, n)		(*VNET_VNET_PTR((vnet), n))
274 
275 #define	VNET_PTR(n)		VNET_VNET_PTR(curvnet, n)
276 #define	VNET(n)			VNET_VNET(curvnet, n)
277 
278 /*
279  * Virtual network stack allocator interfaces from the kernel linker.
280  */
281 void	*vnet_data_alloc(int size);
282 void	 vnet_data_copy(void *start, int size);
283 void	 vnet_data_free(void *start_arg, int size);
284 
285 /*
286  * Sysctl variants for vnet-virtualized global variables.  Include
287  * <sys/sysctl.h> to expose these definitions.
288  *
289  * Note: SYSCTL_PROC() handler functions will need to resolve pointer
290  * arguments themselves, if required.
291  */
292 #ifdef SYSCTL_OID
293 #define	SYSCTL_VNET_INT(parent, nbr, name, access, ptr, val, descr)	\
294 	SYSCTL_OID(parent, nbr, name,					\
295 	    CTLTYPE_INT|CTLFLAG_MPSAFE|CTLFLAG_VNET|(access),		\
296 	    ptr, val, sysctl_handle_int, "I", descr)
297 #define	SYSCTL_VNET_PROC(parent, nbr, name, access, ptr, arg, handler,	\
298 	    fmt, descr)							\
299 	CTASSERT(((access) & CTLTYPE) != 0);				\
300 	SYSCTL_OID(parent, nbr, name, CTLFLAG_VNET|(access), ptr, arg, 	\
301 	    handler, fmt, descr)
302 #define	SYSCTL_VNET_OPAQUE(parent, nbr, name, access, ptr, len, fmt,    \
303 	    descr)							\
304 	SYSCTL_OID(parent, nbr, name,					\
305 	    CTLTYPE_OPAQUE|CTLFLAG_VNET|(access), ptr, len, 		\
306 	    sysctl_handle_opaque, fmt, descr)
307 #define	SYSCTL_VNET_STRING(parent, nbr, name, access, arg, len, descr)	\
308 	SYSCTL_OID(parent, nbr, name,					\
309 	    CTLTYPE_STRING|CTLFLAG_VNET|(access),			\
310 	    arg, len, sysctl_handle_string, "A", descr)
311 #define	SYSCTL_VNET_STRUCT(parent, nbr, name, access, ptr, type, descr)	\
312 	SYSCTL_OID(parent, nbr, name,					\
313 	    CTLTYPE_OPAQUE|CTLFLAG_VNET|(access), ptr,			\
314 	    sizeof(struct type), sysctl_handle_opaque, "S," #type,	\
315 	    descr)
316 #define	SYSCTL_VNET_UINT(parent, nbr, name, access, ptr, val, descr)	\
317 	SYSCTL_OID(parent, nbr, name,					\
318 	    CTLTYPE_UINT|CTLFLAG_MPSAFE|CTLFLAG_VNET|(access),		\
319 	    ptr, val, sysctl_handle_int, "IU", descr)
320 #define	VNET_SYSCTL_ARG(req, arg1) do {					\
321 	if (arg1 != NULL)						\
322 		arg1 = (void *)(TD_TO_VNET((req)->td)->vnet_data_base +	\
323 		    (uintptr_t)(arg1));					\
324 } while (0)
325 #endif /* SYSCTL_OID */
326 
327 /*
328  * Virtual sysinit mechanism, allowing network stack components to declare
329  * startup and shutdown methods to be run when virtual network stack
330  * instances are created and destroyed.
331  */
332 #include <sys/kernel.h>
333 
334 /*
335  * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
336  * destructors.
337  */
338 struct vnet_sysinit {
339 	enum sysinit_sub_id	subsystem;
340 	enum sysinit_elem_order	order;
341 	sysinit_cfunc_t		func;
342 	const void		*arg;
343 	TAILQ_ENTRY(vnet_sysinit) link;
344 };
345 
346 #define	VNET_SYSINIT(ident, subsystem, order, func, arg)		\
347 	static struct vnet_sysinit ident ## _vnet_init = {		\
348 		subsystem,						\
349 		order,							\
350 		(sysinit_cfunc_t)(sysinit_nfunc_t)func,			\
351 		(arg)							\
352 	};								\
353 	SYSINIT(vnet_init_ ## ident, subsystem, order,			\
354 	    vnet_register_sysinit, &ident ## _vnet_init);		\
355 	SYSUNINIT(vnet_init_ ## ident, subsystem, order,		\
356 	    vnet_deregister_sysinit, &ident ## _vnet_init)
357 
358 #define	VNET_SYSUNINIT(ident, subsystem, order, func, arg)		\
359 	static struct vnet_sysinit ident ## _vnet_uninit = {		\
360 		subsystem,						\
361 		order,							\
362 		(sysinit_cfunc_t)(sysinit_nfunc_t)func,			\
363 		(arg)							\
364 	};								\
365 	SYSINIT(vnet_uninit_ ## ident, subsystem, order,		\
366 	    vnet_register_sysuninit, &ident ## _vnet_uninit);		\
367 	SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,		\
368 	    vnet_deregister_sysuninit, &ident ## _vnet_uninit)
369 
370 /*
371  * Run per-vnet sysinits or sysuninits during vnet creation/destruction.
372  */
373 void	 vnet_sysinit(void);
374 void	 vnet_sysuninit(void);
375 
376 /*
377  * Interfaces for managing per-vnet constructors and destructors.
378  */
379 void	vnet_register_sysinit(void *arg);
380 void	vnet_register_sysuninit(void *arg);
381 void	vnet_deregister_sysinit(void *arg);
382 void	vnet_deregister_sysuninit(void *arg);
383 
384 /*
385  * EVENTHANDLER(9) extensions.
386  */
387 #include <sys/eventhandler.h>
388 
389 void	vnet_global_eventhandler_iterator_func(void *, ...);
390 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
391 do {									\
392 	if (IS_DEFAULT_VNET(curvnet)) {					\
393 		(tag) = vimage_eventhandler_register(NULL, #name, func,	\
394 		    arg, priority,					\
395 		    vnet_global_eventhandler_iterator_func);		\
396 	}								\
397 } while(0)
398 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)	\
399 do {									\
400 	if (IS_DEFAULT_VNET(curvnet)) {					\
401 		vimage_eventhandler_register(NULL, #name, func,		\
402 		    arg, priority,					\
403 		    vnet_global_eventhandler_iterator_func);		\
404 	}								\
405 } while(0)
406 
407 #else /* !VIMAGE */
408 
409 /*
410  * Various virtual network stack macros compile to no-ops without VIMAGE.
411  */
412 #define	curvnet			NULL
413 
414 #define	VNET_ASSERT(exp, msg)
415 #define	CURVNET_SET(arg)
416 #define	CURVNET_SET_QUIET(arg)
417 #define	CURVNET_RESTORE()
418 
419 #define	VNET_LIST_RLOCK()
420 #define	VNET_LIST_RLOCK_NOSLEEP()
421 #define	VNET_LIST_RUNLOCK()
422 #define	VNET_LIST_RUNLOCK_NOSLEEP()
423 #define	VNET_ITERATOR_DECL(arg)
424 #define	VNET_FOREACH(arg)
425 
426 #define	IS_DEFAULT_VNET(arg)	1
427 #define	CRED_TO_VNET(cr)	NULL
428 #define	TD_TO_VNET(td)		NULL
429 #define	P_TO_VNET(p)		NULL
430 
431 /*
432  * Versions of the VNET macros that compile to normal global variables and
433  * standard sysctl definitions.
434  */
435 #define	VNET_NAME(n)		n
436 #define	VNET_DECLARE(t, n)	extern t n
437 #define	VNET_DEFINE(t, n)	t n
438 #define	_VNET_PTR(b, n)		&VNET_NAME(n)
439 
440 /*
441  * Virtualized global variable accessor macros.
442  */
443 #define	VNET_VNET_PTR(vnet, n)		(&(n))
444 #define	VNET_VNET(vnet, n)		(n)
445 
446 #define	VNET_PTR(n)		(&(n))
447 #define	VNET(n)			(n)
448 
449 /*
450  * When VIMAGE isn't compiled into the kernel, virtaulized SYSCTLs simply
451  * become normal SYSCTLs.
452  */
453 #ifdef SYSCTL_OID
454 #define	SYSCTL_VNET_INT(parent, nbr, name, access, ptr, val, descr)	\
455 	SYSCTL_INT(parent, nbr, name, access, ptr, val, descr)
456 #define	SYSCTL_VNET_PROC(parent, nbr, name, access, ptr, arg, handler,	\
457 	    fmt, descr)							\
458 	SYSCTL_PROC(parent, nbr, name, access, ptr, arg, handler, fmt,	\
459 	    descr)
460 #define	SYSCTL_VNET_OPAQUE(parent, nbr, name, access, ptr, len, fmt,    \
461 	    descr)							\
462 	SYSCTL_OPAQUE(parent, nbr, name, access, ptr, len, fmt, descr)
463 #define	SYSCTL_VNET_STRING(parent, nbr, name, access, arg, len, descr)	\
464 	SYSCTL_STRING(parent, nbr, name, access, arg, len, descr)
465 #define	SYSCTL_VNET_STRUCT(parent, nbr, name, access, ptr, type, descr)	\
466 	SYSCTL_STRUCT(parent, nbr, name, access, ptr, type, descr)
467 #define	SYSCTL_VNET_UINT(parent, nbr, name, access, ptr, val, descr)	\
468 	SYSCTL_UINT(parent, nbr, name, access, ptr, val, descr)
469 #define	VNET_SYSCTL_ARG(req, arg1)
470 #endif /* SYSCTL_OID */
471 
472 /*
473  * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
474  * map into normal sysinits, which have the same ordering properties.
475  */
476 #define	VNET_SYSINIT(ident, subsystem, order, func, arg)		\
477 	SYSINIT(ident, subsystem, order, func, arg)
478 #define	VNET_SYSUNINIT(ident, subsystem, order, func, arg)		\
479 	SYSUNINIT(ident, subsystem, order, func, arg)
480 
481 /*
482  * Without VIMAGE revert to the default implementation.
483  */
484 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
485 	(tag) = eventhandler_register(NULL, #name, func, arg, priority)
486 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)	\
487 	eventhandler_register(NULL, #name, func, arg, priority)
488 #endif /* VIMAGE */
489 #endif /* _KERNEL */
490 
491 #endif /* !_NET_VNET_H_ */
492