sys/net/vnet.h

   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
  69 struct 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)     \
 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,                                          \
 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  */
 158 extern uintptr_t        *__start_set_vnet;
 159 __GLOBL(__start_set_vnet);
 160 extern 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  */
 169 struct vnet *vnet_alloc(void);
 170 void    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
 193 void 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
 244 extern 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  */
 256 LIST_HEAD(vnet_list_head, vnet);
 257 extern struct vnet_list_head vnet_head;
 258 extern struct rwlock vnet_rwlock;
 259 extern 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  */
 310 void    *vnet_data_alloc(int size);
 311 void     vnet_data_copy(void *start, int size);
 312 void     vnet_data_free(void *start_arg, int size);
 313
 314 /*
 315  * Interfaces to manipulate the initial values of virtualized global variables.
 316  */
 317 void    vnet_save_init(void *, size_t);
 318 void    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  */
 331 struct 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  */
 370 void    vnet_register_sysinit(void *arg);
 371 void    vnet_register_sysuninit(void *arg);
 372 void    vnet_deregister_sysinit(void *arg);
 373 void    vnet_deregister_sysuninit(void *arg);
 374
 375 /*
 376  * EVENTHANDLER(9) extensions.
 377  */
 378 #include <sys/eventhandler.h>
 379
 380 void    vnet_global_eventhandler_iterator_func(void *, ...);
 381 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 382 do {                                                                    \
 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)    \
 390 do {                                                                    \
 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_ */