sys/net/vnet.h

   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         u_int                    vnet_state;    /* SI_SUB_* */
  74         void                    *vnet_data_mem;
  75         uintptr_t                vnet_data_base;
  76 };
  77 #define VNET_MAGIC_N    0x3e0d8f29
  78
  79 /*
  80  * These two virtual network stack allocator definitions are also required
  81  * for libkvm so that it can evaluate virtualized global variables.
  82  */
  83 #define VNET_SETNAME            "set_vnet"
  84 #define VNET_SYMPREFIX          "vnet_entry_"
  85 #endif
  86
  87 #ifdef _KERNEL
  88
  89 #define VNET_PCPUSTAT_DECLARE(type, name)       \
  90     VNET_DECLARE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  91
  92 #define VNET_PCPUSTAT_DEFINE(type, name)        \
  93     VNET_DEFINE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  94
  95 #define VNET_PCPUSTAT_ALLOC(name, wait) \
  96     COUNTER_ARRAY_ALLOC(VNET(name), \
  97         sizeof(VNET(name)) / sizeof(counter_u64_t), (wait))
  98
  99 #define VNET_PCPUSTAT_FREE(name)        \
 100     COUNTER_ARRAY_FREE(VNET(name), sizeof(VNET(name)) / sizeof(counter_u64_t))
 101
 102 #define VNET_PCPUSTAT_ADD(type, name, f, v)     \
 103     counter_u64_add(VNET(name)[offsetof(type, f) / sizeof(uint64_t)], (v))
 104
 105 #define VNET_PCPUSTAT_FETCH(type, name, f)      \
 106     counter_u64_fetch(VNET(name)[offsetof(type, f) / sizeof(uint64_t)])
 107
 108 #define VNET_PCPUSTAT_SYSINIT(name)     \
 109 static void                             \
 110 vnet_##name##_init(const void *unused)  \
 111 {                                       \
 112         VNET_PCPUSTAT_ALLOC(name, M_WAITOK);    \
 113 }                                       \
 114 VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_INIT_IF,                    \
 115     SI_ORDER_FIRST, vnet_ ## name ## _init, NULL)
 116
 117 #define VNET_PCPUSTAT_SYSUNINIT(name)                                   \
 118 static void                                                             \
 119 vnet_##name##_uninit(const void *unused)                                \
 120 {                                                                       \
 121         VNET_PCPUSTAT_FREE(name);                                       \
 122 }                                                                       \
 123 VNET_SYSUNINIT(vnet_ ## name ## _uninit, SI_SUB_INIT_IF,                \
 124     SI_ORDER_FIRST, vnet_ ## name ## _uninit, NULL)
 125
 126 #ifdef SYSCTL_OID
 127 #define SYSCTL_VNET_PCPUSTAT(parent, nbr, name, type, array, desc)      \
 128 static int                                                              \
 129 array##_sysctl(SYSCTL_HANDLER_ARGS)                                     \
 130 {                                                                       \
 131         type s;                                                         \
 132         CTASSERT((sizeof(type) / sizeof(uint64_t)) ==                   \
 133             (sizeof(VNET(array)) / sizeof(counter_u64_t)));             \
 134         COUNTER_ARRAY_COPY(VNET(array), &s, sizeof(type) / sizeof(uint64_t));\
 135         if (req->newptr)                                                \
 136                 COUNTER_ARRAY_ZERO(VNET(array),                         \
 137                     sizeof(type) / sizeof(uint64_t));                   \
 138         return (SYSCTL_OUT(req, &s, sizeof(type)));                     \
 139 }                                                                       \
 140 SYSCTL_PROC(parent, nbr, name, CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_RW, \
 141     NULL, 0, array ## _sysctl, "I", desc)
 142 #endif /* SYSCTL_OID */
 143
 144 #ifdef VIMAGE
 145 #include <sys/lock.h>
 146 #include <sys/proc.h>                   /* for struct thread */
 147 #include <sys/rwlock.h>
 148 #include <sys/sx.h>
 149
 150 /*
 151  * Location of the kernel's 'set_vnet' linker set.
 152  */
 153 extern uintptr_t        *__start_set_vnet;
 154 __GLOBL(__start_set_vnet);
 155 extern uintptr_t        *__stop_set_vnet;
 156 __GLOBL(__stop_set_vnet);
 157
 158 #define VNET_START      (uintptr_t)&__start_set_vnet
 159 #define VNET_STOP       (uintptr_t)&__stop_set_vnet
 160
 161 /*
 162  * Functions to allocate and destroy virtual network stacks.
 163  */
 164 struct vnet *vnet_alloc(void);
 165 void    vnet_destroy(struct vnet *vnet);
 166
 167 /*
 168  * The current virtual network stack -- we may wish to move this to struct
 169  * pcpu in the future.
 170  */
 171 #define curvnet curthread->td_vnet
 172
 173 /*
 174  * Various macros -- get and set the current network stack, but also
 175  * assertions.
 176  */
 177 #if defined(INVARIANTS) || defined(VNET_DEBUG)
 178 #define VNET_ASSERT(exp, msg)   do {                                    \
 179         if (!(exp))                                                     \
 180                 panic msg;                                              \
 181 } while (0)
 182 #else
 183 #define VNET_ASSERT(exp, msg)   do {                                    \
 184 } while (0)
 185 #endif
 186
 187 #ifdef VNET_DEBUG
 188 void vnet_log_recursion(struct vnet *, const char *, int);
 189
 190 #define CURVNET_SET_QUIET(arg)                                          \
 191         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 192             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 193             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 194         struct vnet *saved_vnet = curvnet;                              \
 195         const char *saved_vnet_lpush = curthread->td_vnet_lpush;        \
 196         curvnet = arg;                                                  \
 197         curthread->td_vnet_lpush = __func__;
 198
 199 #define CURVNET_SET_VERBOSE(arg)                                        \
 200         CURVNET_SET_QUIET(arg)                                          \
 201         if (saved_vnet)                                                 \
 202                 vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
 203
 204 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 205
 206 #define CURVNET_RESTORE()                                               \
 207         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 208             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 209             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 210             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 211         curvnet = saved_vnet;                                           \
 212         curthread->td_vnet_lpush = saved_vnet_lpush;
 213 #else /* !VNET_DEBUG */
 214
 215 #define CURVNET_SET_QUIET(arg)                                          \
 216         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 217             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 218             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 219         struct vnet *saved_vnet = curvnet;                              \
 220         curvnet = arg;
 221
 222 #define CURVNET_SET_VERBOSE(arg)                                        \
 223         CURVNET_SET_QUIET(arg)
 224
 225 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 226
 227 #define CURVNET_RESTORE()                                               \
 228         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 229             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 230             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 231             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 232         curvnet = saved_vnet;
 233 #endif /* VNET_DEBUG */
 234
 235 extern struct vnet *vnet0;
 236 #define IS_DEFAULT_VNET(arg)    ((arg) == vnet0)
 237
 238 #define CRED_TO_VNET(cr)        (cr)->cr_prison->pr_vnet
 239 #define TD_TO_VNET(td)          CRED_TO_VNET((td)->td_ucred)
 240 #define P_TO_VNET(p)            CRED_TO_VNET((p)->p_ucred)
 241
 242 /*
 243  * Global linked list of all virtual network stacks, along with read locks to
 244  * access it.  If a caller may sleep while accessing the list, it must use
 245  * the sleepable lock macros.
 246  */
 247 LIST_HEAD(vnet_list_head, vnet);
 248 extern struct vnet_list_head vnet_head;
 249 extern struct rwlock vnet_rwlock;
 250 extern struct sx vnet_sxlock;
 251
 252 #define VNET_LIST_RLOCK()               sx_slock(&vnet_sxlock)
 253 #define VNET_LIST_RLOCK_NOSLEEP()       rw_rlock(&vnet_rwlock)
 254 #define VNET_LIST_RUNLOCK()             sx_sunlock(&vnet_sxlock)
 255 #define VNET_LIST_RUNLOCK_NOSLEEP()     rw_runlock(&vnet_rwlock)
 256
 257 /*
 258  * Iteration macros to walk the global list of virtual network stacks.
 259  */
 260 #define VNET_ITERATOR_DECL(arg) struct vnet *arg
 261 #define VNET_FOREACH(arg)       LIST_FOREACH((arg), &vnet_head, vnet_le)
 262
 263 /*
 264  * Virtual network stack memory allocator, which allows global variables to
 265  * be automatically instantiated for each network stack instance.
 266  */
 267 #define VNET_NAME(n)            vnet_entry_##n
 268 #define VNET_DECLARE(t, n)      extern t VNET_NAME(n)
 269 #define VNET_DEFINE(t, n)       t VNET_NAME(n) __section(VNET_SETNAME) __used
 270 #define _VNET_PTR(b, n)         (__typeof(VNET_NAME(n))*)               \
 271                                     ((b) + (uintptr_t)&VNET_NAME(n))
 272
 273 #define _VNET(b, n)             (*_VNET_PTR(b, n))
 274
 275 /*
 276  * Virtualized global variable accessor macros.
 277  */
 278 #define VNET_VNET_PTR(vnet, n)          _VNET_PTR((vnet)->vnet_data_base, n)
 279 #define VNET_VNET(vnet, n)              (*VNET_VNET_PTR((vnet), n))
 280
 281 #define VNET_PTR(n)             VNET_VNET_PTR(curvnet, n)
 282 #define VNET(n)                 VNET_VNET(curvnet, n)
 283
 284 /*
 285  * Virtual network stack allocator interfaces from the kernel linker.
 286  */
 287 void    *vnet_data_alloc(int size);
 288 void     vnet_data_copy(void *start, int size);
 289 void     vnet_data_free(void *start_arg, int size);
 290
 291 /*
 292  * Virtual sysinit mechanism, allowing network stack components to declare
 293  * startup and shutdown methods to be run when virtual network stack
 294  * instances are created and destroyed.
 295  */
 296 #include <sys/kernel.h>
 297
 298 /*
 299  * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
 300  * destructors.
 301  */
 302 struct vnet_sysinit {
 303         enum sysinit_sub_id     subsystem;
 304         enum sysinit_elem_order order;
 305         sysinit_cfunc_t         func;
 306         const void              *arg;
 307         TAILQ_ENTRY(vnet_sysinit) link;
 308 };
 309
 310 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 311         static struct vnet_sysinit ident ## _vnet_init = {              \
 312                 subsystem,                                              \
 313                 order,                                                  \
 314                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 315                 (arg)                                                   \
 316         };                                                              \
 317         SYSINIT(vnet_init_ ## ident, subsystem, order,                  \
 318             vnet_register_sysinit, &ident ## _vnet_init);               \
 319         SYSUNINIT(vnet_init_ ## ident, subsystem, order,                \
 320             vnet_deregister_sysinit, &ident ## _vnet_init)
 321
 322 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 323         static struct vnet_sysinit ident ## _vnet_uninit = {            \
 324                 subsystem,                                              \
 325                 order,                                                  \
 326                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 327                 (arg)                                                   \
 328         };                                                              \
 329         SYSINIT(vnet_uninit_ ## ident, subsystem, order,                \
 330             vnet_register_sysuninit, &ident ## _vnet_uninit);           \
 331         SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,              \
 332             vnet_deregister_sysuninit, &ident ## _vnet_uninit)
 333
 334 /*
 335  * Run per-vnet sysinits or sysuninits during vnet creation/destruction.
 336  */
 337 void     vnet_sysinit(void);
 338 void     vnet_sysuninit(void);
 339
 340 /*
 341  * Interfaces for managing per-vnet constructors and destructors.
 342  */
 343 void    vnet_register_sysinit(void *arg);
 344 void    vnet_register_sysuninit(void *arg);
 345 void    vnet_deregister_sysinit(void *arg);
 346 void    vnet_deregister_sysuninit(void *arg);
 347
 348 /*
 349  * EVENTHANDLER(9) extensions.
 350  */
 351 #include <sys/eventhandler.h>
 352
 353 void    vnet_global_eventhandler_iterator_func(void *, ...);
 354 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 355 do {                                                                    \
 356         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 357                 (tag) = vimage_eventhandler_register(NULL, #name, func, \
 358                     arg, priority,                                      \
 359                     vnet_global_eventhandler_iterator_func);            \
 360         }                                                               \
 361 } while(0)
 362 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 363 do {                                                                    \
 364         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 365                 vimage_eventhandler_register(NULL, #name, func,         \
 366                     arg, priority,                                      \
 367                     vnet_global_eventhandler_iterator_func);            \
 368         }                                                               \
 369 } while(0)
 370
 371 #else /* !VIMAGE */
 372
 373 /*
 374  * Various virtual network stack macros compile to no-ops without VIMAGE.
 375  */
 376 #define curvnet                 NULL
 377
 378 #define VNET_ASSERT(exp, msg)
 379 #define CURVNET_SET(arg)
 380 #define CURVNET_SET_QUIET(arg)
 381 #define CURVNET_RESTORE()
 382
 383 #define VNET_LIST_RLOCK()
 384 #define VNET_LIST_RLOCK_NOSLEEP()
 385 #define VNET_LIST_RUNLOCK()
 386 #define VNET_LIST_RUNLOCK_NOSLEEP()
 387 #define VNET_ITERATOR_DECL(arg)
 388 #define VNET_FOREACH(arg)
 389
 390 #define IS_DEFAULT_VNET(arg)    1
 391 #define CRED_TO_VNET(cr)        NULL
 392 #define TD_TO_VNET(td)          NULL
 393 #define P_TO_VNET(p)            NULL
 394
 395 /*
 396  * Versions of the VNET macros that compile to normal global variables and
 397  * standard sysctl definitions.
 398  */
 399 #define VNET_NAME(n)            n
 400 #define VNET_DECLARE(t, n)      extern t n
 401 #define VNET_DEFINE(t, n)       t n
 402 #define _VNET_PTR(b, n)         &VNET_NAME(n)
 403
 404 /*
 405  * Virtualized global variable accessor macros.
 406  */
 407 #define VNET_VNET_PTR(vnet, n)          (&(n))
 408 #define VNET_VNET(vnet, n)              (n)
 409
 410 #define VNET_PTR(n)             (&(n))
 411 #define VNET(n)                 (n)
 412
 413 /*
 414  * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
 415  * map into normal sysinits, which have the same ordering properties.
 416  */
 417 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 418         SYSINIT(ident, subsystem, order, func, arg)
 419 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 420         SYSUNINIT(ident, subsystem, order, func, arg)
 421
 422 /*
 423  * Without VIMAGE revert to the default implementation.
 424  */
 425 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 426         (tag) = eventhandler_register(NULL, #name, func, arg, priority)
 427 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 428         eventhandler_register(NULL, #name, func, arg, priority)
 429 #endif /* VIMAGE */
 430 #endif /* _KERNEL */
 431
 432 #endif /* !_NET_VNET_H_ */