sys/net/vnet.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   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  * $FreeBSD$
  38  */
  39
  40 /*-
  41  * This header file defines several sets of interfaces supporting virtualized
  42  * network stacks:
  43  *
  44  * - Definition of 'struct vnet' and functions and macros to allocate/free/
  45  *   manipulate it.
  46  *
  47  * - A virtual network stack memory allocator, which provides support for
  48  *   virtualized global variables via a special linker set, set_vnet.
  49  *
  50  * - Virtualized sysinits/sysuninits, which allow constructors and
  51  *   destructors to be run for each network stack subsystem as virtual
  52  *   instances are created and destroyed.
  53  *
  54  * If VIMAGE isn't compiled into the kernel, virtualized global variables
  55  * compile to normal global variables, and virtualized sysinits to regular
  56  * sysinits.
  57  */
  58
  59 #ifndef _NET_VNET_H_
  60 #define _NET_VNET_H_
  61
  62 /*
  63  * struct vnet describes a virtualized network stack, and is primarily a
  64  * pointer to storage for virtualized global variables.  Expose to userspace
  65  * as required for libkvm.
  66  */
  67 #if defined(_KERNEL) || defined(_WANT_VNET)
  68 #include <sys/queue.h>
  69
  70 struct vnet {
  71         LIST_ENTRY(vnet)         vnet_le;       /* all vnets list */
  72         u_int                    vnet_magic_n;
  73         u_int                    vnet_ifcnt;
  74         u_int                    vnet_sockcnt;
  75         u_int                    vnet_state;    /* SI_SUB_* */
  76         void                    *vnet_data_mem;
  77         uintptr_t                vnet_data_base;
  78 };
  79 #define VNET_MAGIC_N    0x3e0d8f29
  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
  97 #define VNET_PCPUSTAT_ALLOC(name, wait) \
  98     COUNTER_ARRAY_ALLOC(VNET(name), \
  99         sizeof(VNET(name)) / sizeof(counter_u64_t), (wait))
 100
 101 #define VNET_PCPUSTAT_FREE(name)        \
 102     COUNTER_ARRAY_FREE(VNET(name), sizeof(VNET(name)) / sizeof(counter_u64_t))
 103
 104 #define VNET_PCPUSTAT_ADD(type, name, f, v)     \
 105     counter_u64_add(VNET(name)[offsetof(type, f) / sizeof(uint64_t)], (v))
 106
 107 #define VNET_PCPUSTAT_FETCH(type, name, f)      \
 108     counter_u64_fetch(VNET(name)[offsetof(type, f) / sizeof(uint64_t)])
 109
 110 #define VNET_PCPUSTAT_SYSINIT(name)     \
 111 static void                             \
 112 vnet_##name##_init(const void *unused)  \
 113 {                                       \
 114         VNET_PCPUSTAT_ALLOC(name, M_WAITOK);    \
 115 }                                       \
 116 VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_INIT_IF,                    \
 117     SI_ORDER_FIRST, vnet_ ## name ## _init, NULL)
 118
 119 #define VNET_PCPUSTAT_SYSUNINIT(name)                                   \
 120 static void                                                             \
 121 vnet_##name##_uninit(const void *unused)                                \
 122 {                                                                       \
 123         VNET_PCPUSTAT_FREE(name);                                       \
 124 }                                                                       \
 125 VNET_SYSUNINIT(vnet_ ## name ## _uninit, SI_SUB_INIT_IF,                \
 126     SI_ORDER_FIRST, vnet_ ## name ## _uninit, NULL)
 127
 128 #ifdef SYSCTL_OID
 129 #define SYSCTL_VNET_PCPUSTAT(parent, nbr, name, type, array, desc)      \
 130 static int                                                              \
 131 array##_sysctl(SYSCTL_HANDLER_ARGS)                                     \
 132 {                                                                       \
 133         type s;                                                         \
 134         CTASSERT((sizeof(type) / sizeof(uint64_t)) ==                   \
 135             (sizeof(VNET(array)) / sizeof(counter_u64_t)));             \
 136         COUNTER_ARRAY_COPY(VNET(array), &s, sizeof(type) / sizeof(uint64_t));\
 137         if (req->newptr)                                                \
 138                 COUNTER_ARRAY_ZERO(VNET(array),                         \
 139                     sizeof(type) / sizeof(uint64_t));                   \
 140         return (SYSCTL_OUT(req, &s, sizeof(type)));                     \
 141 }                                                                       \
 142 SYSCTL_PROC(parent, nbr, name, CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_RW, \
 143     NULL, 0, array ## _sysctl, "I", desc)
 144 #endif /* SYSCTL_OID */
 145
 146 #ifdef VIMAGE
 147 #include <sys/lock.h>
 148 #include <sys/proc.h>                   /* for struct thread */
 149 #include <sys/rwlock.h>
 150 #include <sys/sx.h>
 151
 152 /*
 153  * Location of the kernel's 'set_vnet' linker set.
 154  */
 155 extern uintptr_t        *__start_set_vnet;
 156 __GLOBL(__start_set_vnet);
 157 extern uintptr_t        *__stop_set_vnet;
 158 __GLOBL(__stop_set_vnet);
 159
 160 #define VNET_START      (uintptr_t)&__start_set_vnet
 161 #define VNET_STOP       (uintptr_t)&__stop_set_vnet
 162
 163 /*
 164  * Functions to allocate and destroy virtual network stacks.
 165  */
 166 struct vnet *vnet_alloc(void);
 167 void    vnet_destroy(struct vnet *vnet);
 168
 169 /*
 170  * The current virtual network stack -- we may wish to move this to struct
 171  * pcpu in the future.
 172  */
 173 #define curvnet curthread->td_vnet
 174
 175 /*
 176  * Various macros -- get and set the current network stack, but also
 177  * assertions.
 178  */
 179 #if defined(INVARIANTS) || defined(VNET_DEBUG)
 180 #define VNET_ASSERT(exp, msg)   do {                                    \
 181         if (!(exp))                                                     \
 182                 panic msg;                                              \
 183 } while (0)
 184 #else
 185 #define VNET_ASSERT(exp, msg)   do {                                    \
 186 } while (0)
 187 #endif
 188
 189 #ifdef VNET_DEBUG
 190 void vnet_log_recursion(struct vnet *, const char *, int);
 191
 192 #define CURVNET_SET_QUIET(arg)                                          \
 193         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 194             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 195             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 196         struct vnet *saved_vnet = curvnet;                              \
 197         const char *saved_vnet_lpush = curthread->td_vnet_lpush;        \
 198         curvnet = arg;                                                  \
 199         curthread->td_vnet_lpush = __func__;
 200
 201 #define CURVNET_SET_VERBOSE(arg)                                        \
 202         CURVNET_SET_QUIET(arg)                                          \
 203         if (saved_vnet)                                                 \
 204                 vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
 205
 206 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 207
 208 #define CURVNET_RESTORE()                                               \
 209         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 210             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 211             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 212             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 213         curvnet = saved_vnet;                                           \
 214         curthread->td_vnet_lpush = saved_vnet_lpush;
 215 #else /* !VNET_DEBUG */
 216
 217 #define CURVNET_SET_QUIET(arg)                                          \
 218         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 219             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 220             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 221         struct vnet *saved_vnet = curvnet;                              \
 222         curvnet = arg;
 223
 224 #define CURVNET_SET_VERBOSE(arg)                                        \
 225         CURVNET_SET_QUIET(arg)
 226
 227 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 228
 229 #define CURVNET_RESTORE()                                               \
 230         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 231             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 232             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 233             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 234         curvnet = saved_vnet;
 235 #endif /* VNET_DEBUG */
 236
 237 extern struct vnet *vnet0;
 238 #define IS_DEFAULT_VNET(arg)    ((arg) == vnet0)
 239
 240 #define CRED_TO_VNET(cr)        (cr)->cr_prison->pr_vnet
 241 #define TD_TO_VNET(td)          CRED_TO_VNET((td)->td_ucred)
 242 #define P_TO_VNET(p)            CRED_TO_VNET((p)->p_ucred)
 243
 244 /*
 245  * Global linked list of all virtual network stacks, along with read locks to
 246  * access it.  If a caller may sleep while accessing the list, it must use
 247  * the sleepable lock macros.
 248  */
 249 LIST_HEAD(vnet_list_head, vnet);
 250 extern struct vnet_list_head vnet_head;
 251 extern struct rwlock vnet_rwlock;
 252 extern struct sx vnet_sxlock;
 253
 254 #define VNET_LIST_RLOCK()               sx_slock(&vnet_sxlock)
 255 #define VNET_LIST_RLOCK_NOSLEEP()       rw_rlock(&vnet_rwlock)
 256 #define VNET_LIST_RUNLOCK()             sx_sunlock(&vnet_sxlock)
 257 #define VNET_LIST_RUNLOCK_NOSLEEP()     rw_runlock(&vnet_rwlock)
 258
 259 /*
 260  * Iteration macros to walk the global list of virtual network stacks.
 261  */
 262 #define VNET_ITERATOR_DECL(arg) struct vnet *arg
 263 #define VNET_FOREACH(arg)       LIST_FOREACH((arg), &vnet_head, vnet_le)
 264
 265 /*
 266  * Virtual network stack memory allocator, which allows global variables to
 267  * be automatically instantiated for each network stack instance.
 268  */
 269 #define VNET_NAME(n)            vnet_entry_##n
 270 #define VNET_DECLARE(t, n)      extern t VNET_NAME(n)
 271 #define VNET_DEFINE(t, n)       t VNET_NAME(n) __section(VNET_SETNAME) __used
 272 #define _VNET_PTR(b, n)         (__typeof(VNET_NAME(n))*)               \
 273                                     ((b) + (uintptr_t)&VNET_NAME(n))
 274
 275 #define _VNET(b, n)             (*_VNET_PTR(b, n))
 276
 277 /*
 278  * Virtualized global variable accessor macros.
 279  */
 280 #define VNET_VNET_PTR(vnet, n)          _VNET_PTR((vnet)->vnet_data_base, n)
 281 #define VNET_VNET(vnet, n)              (*VNET_VNET_PTR((vnet), n))
 282
 283 #define VNET_PTR(n)             VNET_VNET_PTR(curvnet, n)
 284 #define VNET(n)                 VNET_VNET(curvnet, n)
 285
 286 /*
 287  * Virtual network stack allocator interfaces from the kernel linker.
 288  */
 289 void    *vnet_data_alloc(int size);
 290 void     vnet_data_copy(void *start, int size);
 291 void     vnet_data_free(void *start_arg, int size);
 292
 293 /*
 294  * Virtual sysinit mechanism, allowing network stack components to declare
 295  * startup and shutdown methods to be run when virtual network stack
 296  * instances are created and destroyed.
 297  */
 298 #include <sys/kernel.h>
 299
 300 /*
 301  * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
 302  * destructors.
 303  */
 304 struct vnet_sysinit {
 305         enum sysinit_sub_id     subsystem;
 306         enum sysinit_elem_order order;
 307         sysinit_cfunc_t         func;
 308         const void              *arg;
 309         TAILQ_ENTRY(vnet_sysinit) link;
 310 };
 311
 312 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 313         static struct vnet_sysinit ident ## _vnet_init = {              \
 314                 subsystem,                                              \
 315                 order,                                                  \
 316                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 317                 (arg)                                                   \
 318         };                                                              \
 319         SYSINIT(vnet_init_ ## ident, subsystem, order,                  \
 320             vnet_register_sysinit, &ident ## _vnet_init);               \
 321         SYSUNINIT(vnet_init_ ## ident, subsystem, order,                \
 322             vnet_deregister_sysinit, &ident ## _vnet_init)
 323
 324 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 325         static struct vnet_sysinit ident ## _vnet_uninit = {            \
 326                 subsystem,                                              \
 327                 order,                                                  \
 328                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 329                 (arg)                                                   \
 330         };                                                              \
 331         SYSINIT(vnet_uninit_ ## ident, subsystem, order,                \
 332             vnet_register_sysuninit, &ident ## _vnet_uninit);           \
 333         SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,              \
 334             vnet_deregister_sysuninit, &ident ## _vnet_uninit)
 335
 336 /*
 337  * Run per-vnet sysinits or sysuninits during vnet creation/destruction.
 338  */
 339 void     vnet_sysinit(void);
 340 void     vnet_sysuninit(void);
 341
 342 /*
 343  * Interfaces for managing per-vnet constructors and destructors.
 344  */
 345 void    vnet_register_sysinit(void *arg);
 346 void    vnet_register_sysuninit(void *arg);
 347 void    vnet_deregister_sysinit(void *arg);
 348 void    vnet_deregister_sysuninit(void *arg);
 349
 350 /*
 351  * EVENTHANDLER(9) extensions.
 352  */
 353 #include <sys/eventhandler.h>
 354
 355 void    vnet_global_eventhandler_iterator_func(void *, ...);
 356 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 357 do {                                                                    \
 358         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 359                 (tag) = vimage_eventhandler_register(NULL, #name, func, \
 360                     arg, priority,                                      \
 361                     vnet_global_eventhandler_iterator_func);            \
 362         }                                                               \
 363 } while(0)
 364 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 365 do {                                                                    \
 366         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 367                 vimage_eventhandler_register(NULL, #name, func,         \
 368                     arg, priority,                                      \
 369                     vnet_global_eventhandler_iterator_func);            \
 370         }                                                               \
 371 } while(0)
 372
 373 #else /* !VIMAGE */
 374
 375 /*
 376  * Various virtual network stack macros compile to no-ops without VIMAGE.
 377  */
 378 #define curvnet                 NULL
 379
 380 #define VNET_ASSERT(exp, msg)
 381 #define CURVNET_SET(arg)
 382 #define CURVNET_SET_QUIET(arg)
 383 #define CURVNET_RESTORE()
 384
 385 #define VNET_LIST_RLOCK()
 386 #define VNET_LIST_RLOCK_NOSLEEP()
 387 #define VNET_LIST_RUNLOCK()
 388 #define VNET_LIST_RUNLOCK_NOSLEEP()
 389 #define VNET_ITERATOR_DECL(arg)
 390 #define VNET_FOREACH(arg)
 391
 392 #define IS_DEFAULT_VNET(arg)    1
 393 #define CRED_TO_VNET(cr)        NULL
 394 #define TD_TO_VNET(td)          NULL
 395 #define P_TO_VNET(p)            NULL
 396
 397 /*
 398  * Versions of the VNET macros that compile to normal global variables and
 399  * standard sysctl definitions.
 400  */
 401 #define VNET_NAME(n)            n
 402 #define VNET_DECLARE(t, n)      extern t n
 403 #define VNET_DEFINE(t, n)       t n
 404 #define _VNET_PTR(b, n)         &VNET_NAME(n)
 405
 406 /*
 407  * Virtualized global variable accessor macros.
 408  */
 409 #define VNET_VNET_PTR(vnet, n)          (&(n))
 410 #define VNET_VNET(vnet, n)              (n)
 411
 412 #define VNET_PTR(n)             (&(n))
 413 #define VNET(n)                 (n)
 414
 415 /*
 416  * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
 417  * map into normal sysinits, which have the same ordering properties.
 418  */
 419 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 420         SYSINIT(ident, subsystem, order, func, arg)
 421 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 422         SYSUNINIT(ident, subsystem, order, func, arg)
 423
 424 /*
 425  * Without VIMAGE revert to the default implementation.
 426  */
 427 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 428         (tag) = eventhandler_register(NULL, #name, func, arg, priority)
 429 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 430         eventhandler_register(NULL, #name, func, arg, priority)
 431 #endif /* VIMAGE */
 432 #endif /* _KERNEL */
 433
 434 #endif /* !_NET_VNET_H_ */