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 #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)     \
 113 static void                             \
 114 vnet_##name##_init(const void *unused)  \
 115 {                                       \
 116         VNET_PCPUSTAT_ALLOC(name, M_WAITOK);    \
 117 }                                       \
 118 VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_INIT_IF,                    \
 119     SI_ORDER_FIRST, vnet_ ## name ## _init, NULL)
 120
 121 #define VNET_PCPUSTAT_SYSUNINIT(name)                                   \
 122 static void                                                             \
 123 vnet_##name##_uninit(const void *unused)                                \
 124 {                                                                       \
 125         VNET_PCPUSTAT_FREE(name);                                       \
 126 }                                                                       \
 127 VNET_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)      \
 132 static int                                                              \
 133 array##_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 }                                                                       \
 144 SYSCTL_PROC(parent, nbr, name, CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_RW, \
 145     NULL, 0, array ## _sysctl, "I", desc)
 146 #endif /* SYSCTL_OID */
 147
 148 #ifdef VIMAGE
 149 #include <sys/lock.h>
 150 #include <sys/proc.h>                   /* for struct thread */
 151 #include <sys/rwlock.h>
 152 #include <sys/sx.h>
 153
 154 /*
 155  * Location of the kernel's 'set_vnet' linker set.
 156  */
 157 extern uintptr_t        *__start_set_vnet;
 158 __GLOBL(__start_set_vnet);
 159 extern uintptr_t        *__stop_set_vnet;
 160 __GLOBL(__stop_set_vnet);
 161
 162 #define VNET_START      (uintptr_t)&__start_set_vnet
 163 #define VNET_STOP       (uintptr_t)&__stop_set_vnet
 164
 165 /*
 166  * Functions to allocate and destroy virtual network stacks.
 167  */
 168 struct vnet *vnet_alloc(void);
 169 void    vnet_destroy(struct vnet *vnet);
 170
 171 /*
 172  * The current virtual network stack -- we may wish to move this to struct
 173  * pcpu in the future.
 174  */
 175 #define curvnet curthread->td_vnet
 176
 177 /*
 178  * Various macros -- get and set the current network stack, but also
 179  * assertions.
 180  */
 181 #if defined(INVARIANTS) || defined(VNET_DEBUG)
 182 #define VNET_ASSERT(exp, msg)   do {                                    \
 183         if (!(exp))                                                     \
 184                 panic msg;                                              \
 185 } while (0)
 186 #else
 187 #define VNET_ASSERT(exp, msg)   do {                                    \
 188 } while (0)
 189 #endif
 190
 191 #ifdef VNET_DEBUG
 192 void vnet_log_recursion(struct vnet *, const char *, int);
 193
 194 #define CURVNET_SET_QUIET(arg)                                          \
 195         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 196             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 197             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 198         struct vnet *saved_vnet = curvnet;                              \
 199         const char *saved_vnet_lpush = curthread->td_vnet_lpush;        \
 200         curvnet = arg;                                                  \
 201         curthread->td_vnet_lpush = __func__;
 202
 203 #define CURVNET_SET_VERBOSE(arg)                                        \
 204         CURVNET_SET_QUIET(arg)                                          \
 205         if (saved_vnet)                                                 \
 206                 vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
 207
 208 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 209
 210 #define CURVNET_RESTORE()                                               \
 211         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 212             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 213             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 214             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 215         curvnet = saved_vnet;                                           \
 216         curthread->td_vnet_lpush = saved_vnet_lpush;
 217 #else /* !VNET_DEBUG */
 218
 219 #define CURVNET_SET_QUIET(arg)                                          \
 220         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 221             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 222             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 223         struct vnet *saved_vnet = curvnet;                              \
 224         curvnet = arg;
 225
 226 #define CURVNET_SET_VERBOSE(arg)                                        \
 227         CURVNET_SET_QUIET(arg)
 228
 229 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 230
 231 #define CURVNET_RESTORE()                                               \
 232         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 233             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 234             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 235             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 236         curvnet = saved_vnet;
 237 #endif /* VNET_DEBUG */
 238
 239 extern struct vnet *vnet0;
 240 #define IS_DEFAULT_VNET(arg)    ((arg) == vnet0)
 241
 242 #define CRED_TO_VNET(cr)        (cr)->cr_prison->pr_vnet
 243 #define TD_TO_VNET(td)          CRED_TO_VNET((td)->td_ucred)
 244 #define P_TO_VNET(p)            CRED_TO_VNET((p)->p_ucred)
 245
 246 /*
 247  * Global linked list of all virtual network stacks, along with read locks to
 248  * access it.  If a caller may sleep while accessing the list, it must use
 249  * the sleepable lock macros.
 250  */
 251 LIST_HEAD(vnet_list_head, vnet);
 252 extern struct vnet_list_head vnet_head;
 253 extern struct rwlock vnet_rwlock;
 254 extern struct sx vnet_sxlock;
 255
 256 #define VNET_LIST_RLOCK()               sx_slock(&vnet_sxlock)
 257 #define VNET_LIST_RLOCK_NOSLEEP()       rw_rlock(&vnet_rwlock)
 258 #define VNET_LIST_RUNLOCK()             sx_sunlock(&vnet_sxlock)
 259 #define VNET_LIST_RUNLOCK_NOSLEEP()     rw_runlock(&vnet_rwlock)
 260
 261 /*
 262  * Iteration macros to walk the global list of virtual network stacks.
 263  */
 264 #define VNET_ITERATOR_DECL(arg) struct vnet *arg
 265 #define VNET_FOREACH(arg)       LIST_FOREACH((arg), &vnet_head, vnet_le)
 266
 267 /*
 268  * Virtual network stack memory allocator, which allows global variables to
 269  * be automatically instantiated for each network stack instance.
 270  */
 271 #define VNET_NAME(n)            vnet_entry_##n
 272 #define VNET_DECLARE(t, n)      extern t VNET_NAME(n)
 273 /* struct _hack is to stop this from being used with static data */
 274 #define VNET_DEFINE(t, n)       \
 275     struct _hack; t VNET_NAME(n) __section(VNET_SETNAME) __used
 276 #if defined(KLD_MODULE) && (defined(__aarch64__) || defined(__riscv))
 277 /*
 278  * As with DPCPU_DEFINE_STATIC we are unable to mark this data as static
 279  * in modules on some architectures.
 280  */
 281 #define VNET_DEFINE_STATIC(t, n) \
 282     t VNET_NAME(n) __section(VNET_SETNAME) __used
 283 #else
 284 #define VNET_DEFINE_STATIC(t, n) \
 285     static t VNET_NAME(n) __section(VNET_SETNAME) __used
 286 #endif
 287 #define _VNET_PTR(b, n)         (__typeof(VNET_NAME(n))*)               \
 288                                     ((b) + (uintptr_t)&VNET_NAME(n))
 289
 290 #define _VNET(b, n)             (*_VNET_PTR(b, n))
 291
 292 /*
 293  * Virtualized global variable accessor macros.
 294  */
 295 #define VNET_VNET_PTR(vnet, n)          _VNET_PTR((vnet)->vnet_data_base, n)
 296 #define VNET_VNET(vnet, n)              (*VNET_VNET_PTR((vnet), n))
 297
 298 #define VNET_PTR(n)             VNET_VNET_PTR(curvnet, n)
 299 #define VNET(n)                 VNET_VNET(curvnet, n)
 300
 301 /*
 302  * Virtual network stack allocator interfaces from the kernel linker.
 303  */
 304 void    *vnet_data_alloc(int size);
 305 void     vnet_data_copy(void *start, int size);
 306 void     vnet_data_free(void *start_arg, int size);
 307
 308 /*
 309  * Virtual sysinit mechanism, allowing network stack components to declare
 310  * startup and shutdown methods to be run when virtual network stack
 311  * instances are created and destroyed.
 312  */
 313 #include <sys/kernel.h>
 314
 315 /*
 316  * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
 317  * destructors.
 318  */
 319 struct vnet_sysinit {
 320         enum sysinit_sub_id     subsystem;
 321         enum sysinit_elem_order order;
 322         sysinit_cfunc_t         func;
 323         const void              *arg;
 324         TAILQ_ENTRY(vnet_sysinit) link;
 325 };
 326
 327 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 328         static struct vnet_sysinit ident ## _vnet_init = {              \
 329                 subsystem,                                              \
 330                 order,                                                  \
 331                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 332                 (arg)                                                   \
 333         };                                                              \
 334         SYSINIT(vnet_init_ ## ident, subsystem, order,                  \
 335             vnet_register_sysinit, &ident ## _vnet_init);               \
 336         SYSUNINIT(vnet_init_ ## ident, subsystem, order,                \
 337             vnet_deregister_sysinit, &ident ## _vnet_init)
 338
 339 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 340         static struct vnet_sysinit ident ## _vnet_uninit = {            \
 341                 subsystem,                                              \
 342                 order,                                                  \
 343                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 344                 (arg)                                                   \
 345         };                                                              \
 346         SYSINIT(vnet_uninit_ ## ident, subsystem, order,                \
 347             vnet_register_sysuninit, &ident ## _vnet_uninit);           \
 348         SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,              \
 349             vnet_deregister_sysuninit, &ident ## _vnet_uninit)
 350
 351 /*
 352  * Run per-vnet sysinits or sysuninits during vnet creation/destruction.
 353  */
 354 void     vnet_sysinit(void);
 355 void     vnet_sysuninit(void);
 356
 357 /*
 358  * Interfaces for managing per-vnet constructors and destructors.
 359  */
 360 void    vnet_register_sysinit(void *arg);
 361 void    vnet_register_sysuninit(void *arg);
 362 void    vnet_deregister_sysinit(void *arg);
 363 void    vnet_deregister_sysuninit(void *arg);
 364
 365 /*
 366  * EVENTHANDLER(9) extensions.
 367  */
 368 #include <sys/eventhandler.h>
 369
 370 void    vnet_global_eventhandler_iterator_func(void *, ...);
 371 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 372 do {                                                                    \
 373         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 374                 (tag) = vimage_eventhandler_register(NULL, #name, func, \
 375                     arg, priority,                                      \
 376                     vnet_global_eventhandler_iterator_func);            \
 377         }                                                               \
 378 } while(0)
 379 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 380 do {                                                                    \
 381         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 382                 vimage_eventhandler_register(NULL, #name, func,         \
 383                     arg, priority,                                      \
 384                     vnet_global_eventhandler_iterator_func);            \
 385         }                                                               \
 386 } while(0)
 387
 388 #else /* !VIMAGE */
 389
 390 /*
 391  * Various virtual network stack macros compile to no-ops without VIMAGE.
 392  */
 393 #define curvnet                 NULL
 394
 395 #define VNET_ASSERT(exp, msg)
 396 #define CURVNET_SET(arg)
 397 #define CURVNET_SET_QUIET(arg)
 398 #define CURVNET_RESTORE()
 399
 400 #define VNET_LIST_RLOCK()
 401 #define VNET_LIST_RLOCK_NOSLEEP()
 402 #define VNET_LIST_RUNLOCK()
 403 #define VNET_LIST_RUNLOCK_NOSLEEP()
 404 #define VNET_ITERATOR_DECL(arg)
 405 #define VNET_FOREACH(arg)
 406
 407 #define IS_DEFAULT_VNET(arg)    1
 408 #define CRED_TO_VNET(cr)        NULL
 409 #define TD_TO_VNET(td)          NULL
 410 #define P_TO_VNET(p)            NULL
 411
 412 /*
 413  * Versions of the VNET macros that compile to normal global variables and
 414  * standard sysctl definitions.
 415  */
 416 #define VNET_NAME(n)            n
 417 #define VNET_DECLARE(t, n)      extern t n
 418 #define VNET_DEFINE(t, n)       struct _hack; t n
 419 #define VNET_DEFINE_STATIC(t, n)        static t n
 420 #define _VNET_PTR(b, n)         &VNET_NAME(n)
 421
 422 /*
 423  * Virtualized global variable accessor macros.
 424  */
 425 #define VNET_VNET_PTR(vnet, n)          (&(n))
 426 #define VNET_VNET(vnet, n)              (n)
 427
 428 #define VNET_PTR(n)             (&(n))
 429 #define VNET(n)                 (n)
 430
 431 /*
 432  * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
 433  * map into normal sysinits, which have the same ordering properties.
 434  */
 435 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 436         SYSINIT(ident, subsystem, order, func, arg)
 437 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 438         SYSUNINIT(ident, subsystem, order, func, arg)
 439
 440 /*
 441  * Without VIMAGE revert to the default implementation.
 442  */
 443 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 444         (tag) = eventhandler_register(NULL, #name, func, arg, priority)
 445 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 446         eventhandler_register(NULL, #name, func, arg, priority)
 447 #endif /* VIMAGE */
 448 #endif /* _KERNEL */
 449
 450 #endif /* !_NET_VNET_H_ */