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  * $FreeBSD$
  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 <machine/param.h>      /* for CACHE_LINE_SIZE */
  69 #include <sys/queue.h>
  70
  71 struct vnet {
  72         LIST_ENTRY(vnet)         vnet_le;       /* all vnets list */
  73         u_int                    vnet_magic_n;
  74         u_int                    vnet_ifcnt;
  75         u_int                    vnet_sockcnt;
  76         u_int                    vnet_state;    /* SI_SUB_* */
  77         void                    *vnet_data_mem;
  78         uintptr_t                vnet_data_base;
  79         bool                     vnet_shutdown; /* Shutdown in progress. */
  80 } __aligned(CACHE_LINE_SIZE);
  81 #define VNET_MAGIC_N    0x5e4a6f28
  82
  83 /*
  84  * These two virtual network stack allocator definitions are also required
  85  * for libkvm so that it can evaluate virtualized global variables.
  86  */
  87 #define VNET_SETNAME            "set_vnet"
  88 #define VNET_SYMPREFIX          "vnet_entry_"
  89 #endif
  90
  91 #ifdef _KERNEL
  92
  93 #define VNET_PCPUSTAT_DECLARE(type, name)       \
  94     VNET_DECLARE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  95
  96 #define VNET_PCPUSTAT_DEFINE(type, name)        \
  97     VNET_DEFINE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  98 #define VNET_PCPUSTAT_DEFINE_STATIC(type, name) \
  99     VNET_DEFINE_STATIC(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
 100
 101 #define VNET_PCPUSTAT_ALLOC(name, wait) \
 102     COUNTER_ARRAY_ALLOC(VNET(name), \
 103         sizeof(VNET(name)) / sizeof(counter_u64_t), (wait))
 104
 105 #define VNET_PCPUSTAT_FREE(name)        \
 106     COUNTER_ARRAY_FREE(VNET(name), sizeof(VNET(name)) / sizeof(counter_u64_t))
 107
 108 #define VNET_PCPUSTAT_ADD(type, name, f, v)     \
 109     counter_u64_add(VNET(name)[offsetof(type, f) / sizeof(uint64_t)], (v))
 110
 111 #define VNET_PCPUSTAT_FETCH(type, name, f)      \
 112     counter_u64_fetch(VNET(name)[offsetof(type, f) / sizeof(uint64_t)])
 113
 114 #define VNET_PCPUSTAT_SYSINIT(name)     \
 115 static void                             \
 116 vnet_##name##_init(const void *unused)  \
 117 {                                       \
 118         VNET_PCPUSTAT_ALLOC(name, M_WAITOK);    \
 119 }                                       \
 120 VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_INIT_IF,                    \
 121     SI_ORDER_FIRST, vnet_ ## name ## _init, NULL)
 122
 123 #define VNET_PCPUSTAT_SYSUNINIT(name)                                   \
 124 static void                                                             \
 125 vnet_##name##_uninit(const void *unused)                                \
 126 {                                                                       \
 127         VNET_PCPUSTAT_FREE(name);                                       \
 128 }                                                                       \
 129 VNET_SYSUNINIT(vnet_ ## name ## _uninit, SI_SUB_INIT_IF,                \
 130     SI_ORDER_FIRST, vnet_ ## name ## _uninit, NULL)
 131
 132 #ifdef SYSCTL_OID
 133 #define SYSCTL_VNET_PCPUSTAT(parent, nbr, name, type, array, desc)      \
 134 static int                                                              \
 135 array##_sysctl(SYSCTL_HANDLER_ARGS)                                     \
 136 {                                                                       \
 137         type s;                                                         \
 138         CTASSERT((sizeof(type) / sizeof(uint64_t)) ==                   \
 139             (sizeof(VNET(array)) / sizeof(counter_u64_t)));             \
 140         COUNTER_ARRAY_COPY(VNET(array), &s, sizeof(type) / sizeof(uint64_t));\
 141         if (req->newptr)                                                \
 142                 COUNTER_ARRAY_ZERO(VNET(array),                         \
 143                     sizeof(type) / sizeof(uint64_t));                   \
 144         return (SYSCTL_OUT(req, &s, sizeof(type)));                     \
 145 }                                                                       \
 146 SYSCTL_PROC(parent, nbr, name,                                          \
 147     CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_NEEDGIANT,     \
 148     NULL, 0, array ## _sysctl, "I", desc)
 149 #endif /* SYSCTL_OID */
 150
 151 #ifdef VIMAGE
 152 #include <sys/lock.h>
 153 #include <sys/proc.h>                   /* for struct thread */
 154 #include <sys/rwlock.h>
 155 #include <sys/sx.h>
 156
 157 /*
 158  * Location of the kernel's 'set_vnet' linker set.
 159  */
 160 extern uintptr_t        *__start_set_vnet;
 161 __GLOBL(__start_set_vnet);
 162 extern uintptr_t        *__stop_set_vnet;
 163 __GLOBL(__stop_set_vnet);
 164
 165 #define VNET_START      (uintptr_t)&__start_set_vnet
 166 #define VNET_STOP       (uintptr_t)&__stop_set_vnet
 167
 168 /*
 169  * Functions to allocate and destroy virtual network stacks.
 170  */
 171 struct vnet *vnet_alloc(void);
 172 void    vnet_destroy(struct vnet *vnet);
 173
 174 /*
 175  * The current virtual network stack -- we may wish to move this to struct
 176  * pcpu in the future.
 177  */
 178 #define curvnet curthread->td_vnet
 179
 180 /*
 181  * Various macros -- get and set the current network stack, but also
 182  * assertions.
 183  */
 184 #if defined(INVARIANTS) || defined(VNET_DEBUG)
 185 #define VNET_ASSERT(exp, msg)   do {                                    \
 186         if (!(exp))                                                     \
 187                 panic msg;                                              \
 188 } while (0)
 189 #else
 190 #define VNET_ASSERT(exp, msg)   do {                                    \
 191 } while (0)
 192 #endif
 193
 194 #ifdef VNET_DEBUG
 195 void vnet_log_recursion(struct vnet *, const char *, int);
 196
 197 #define CURVNET_SET_QUIET(arg)                                          \
 198         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 199             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 200             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 201         struct vnet *saved_vnet = curvnet;                              \
 202         const char *saved_vnet_lpush = curthread->td_vnet_lpush;        \
 203         curvnet = arg;                                                  \
 204         curthread->td_vnet_lpush = __func__;
 205
 206 #define CURVNET_SET_VERBOSE(arg)                                        \
 207         CURVNET_SET_QUIET(arg)                                          \
 208         if (saved_vnet)                                                 \
 209                 vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
 210
 211 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 212
 213 #define CURVNET_RESTORE()                                               \
 214         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 215             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 216             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 217             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 218         curvnet = saved_vnet;                                           \
 219         curthread->td_vnet_lpush = saved_vnet_lpush;
 220 #else /* !VNET_DEBUG */
 221
 222 #define CURVNET_SET_QUIET(arg)                                          \
 223         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 224             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 225             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 226         struct vnet *saved_vnet = curvnet;                              \
 227         curvnet = arg;
 228
 229 #define CURVNET_SET_VERBOSE(arg)                                        \
 230         CURVNET_SET_QUIET(arg)
 231
 232 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 233
 234 #define CURVNET_RESTORE()                                               \
 235         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 236             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 237             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 238             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 239         curvnet = saved_vnet;
 240 #endif /* VNET_DEBUG */
 241
 242 #define CURVNET_ASSERT_SET()                                            \
 243         VNET_ASSERT(curvnet != NULL, ("vnet is not set at %s:%d %s()",  \
 244             __FILE__, __LINE__, __func__))
 245
 246 extern struct vnet *vnet0;
 247 #define IS_DEFAULT_VNET(arg)    ((arg) == vnet0)
 248
 249 #define CRED_TO_VNET(cr)        (cr)->cr_prison->pr_vnet
 250 #define TD_TO_VNET(td)          CRED_TO_VNET((td)->td_ucred)
 251 #define P_TO_VNET(p)            CRED_TO_VNET((p)->p_ucred)
 252
 253 /*
 254  * Global linked list of all virtual network stacks, along with read locks to
 255  * access it.  If a caller may sleep while accessing the list, it must use
 256  * the sleepable lock macros.
 257  */
 258 LIST_HEAD(vnet_list_head, vnet);
 259 extern struct vnet_list_head vnet_head;
 260 extern struct rwlock vnet_rwlock;
 261 extern struct sx vnet_sxlock;
 262
 263 #define VNET_LIST_RLOCK()               sx_slock(&vnet_sxlock)
 264 #define VNET_LIST_RLOCK_NOSLEEP()       rw_rlock(&vnet_rwlock)
 265 #define VNET_LIST_RUNLOCK()             sx_sunlock(&vnet_sxlock)
 266 #define VNET_LIST_RUNLOCK_NOSLEEP()     rw_runlock(&vnet_rwlock)
 267
 268 /*
 269  * Iteration macros to walk the global list of virtual network stacks.
 270  */
 271 #define VNET_ITERATOR_DECL(arg) struct vnet *arg
 272 #define VNET_FOREACH(arg)       LIST_FOREACH((arg), &vnet_head, vnet_le)
 273
 274 /*
 275  * Virtual network stack memory allocator, which allows global variables to
 276  * be automatically instantiated for each network stack instance.
 277  */
 278 #define VNET_NAME(n)            vnet_entry_##n
 279 #define VNET_DECLARE(t, n)      extern t VNET_NAME(n)
 280 /* struct _hack is to stop this from being used with static data */
 281 #define VNET_DEFINE(t, n)       \
 282     struct _hack; t VNET_NAME(n) __section(VNET_SETNAME) __used
 283 #if defined(KLD_MODULE) && (defined(__aarch64__) || defined(__riscv) \
 284                 || defined(__powerpc64__))
 285 /*
 286  * As with DPCPU_DEFINE_STATIC we are unable to mark this data as static
 287  * in modules on some architectures.
 288  */
 289 #define VNET_DEFINE_STATIC(t, n) \
 290     t VNET_NAME(n) __section(VNET_SETNAME) __used
 291 #else
 292 #define VNET_DEFINE_STATIC(t, n) \
 293     static t VNET_NAME(n) __section(VNET_SETNAME) __used
 294 #endif
 295 #define _VNET_PTR(b, n)         (__typeof(VNET_NAME(n))*)               \
 296                                     ((b) + (uintptr_t)&VNET_NAME(n))
 297
 298 #define _VNET(b, n)             (*_VNET_PTR(b, n))
 299
 300 /*
 301  * Virtualized global variable accessor macros.
 302  */
 303 #define VNET_VNET_PTR(vnet, n)          _VNET_PTR((vnet)->vnet_data_base, n)
 304 #define VNET_VNET(vnet, n)              (*VNET_VNET_PTR((vnet), n))
 305
 306 #define VNET_PTR(n)             VNET_VNET_PTR(curvnet, n)
 307 #define VNET(n)                 VNET_VNET(curvnet, n)
 308
 309 /*
 310  * Virtual network stack allocator interfaces from the kernel linker.
 311  */
 312 void    *vnet_data_alloc(int size);
 313 void     vnet_data_copy(void *start, int size);
 314 void     vnet_data_free(void *start_arg, int size);
 315
 316 /*
 317  * Virtual sysinit mechanism, allowing network stack components to declare
 318  * startup and shutdown methods to be run when virtual network stack
 319  * instances are created and destroyed.
 320  */
 321 #include <sys/kernel.h>
 322
 323 /*
 324  * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
 325  * destructors.
 326  */
 327 struct vnet_sysinit {
 328         enum sysinit_sub_id     subsystem;
 329         enum sysinit_elem_order order;
 330         sysinit_cfunc_t         func;
 331         const void              *arg;
 332         TAILQ_ENTRY(vnet_sysinit) link;
 333 };
 334
 335 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 336         CTASSERT((subsystem) > SI_SUB_VNET &&                           \
 337             (subsystem) <= SI_SUB_VNET_DONE);                           \
 338         static struct vnet_sysinit ident ## _vnet_init = {              \
 339                 subsystem,                                              \
 340                 order,                                                  \
 341                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 342                 (arg)                                                   \
 343         };                                                              \
 344         SYSINIT(vnet_init_ ## ident, subsystem, order,                  \
 345             vnet_register_sysinit, &ident ## _vnet_init);               \
 346         SYSUNINIT(vnet_init_ ## ident, subsystem, order,                \
 347             vnet_deregister_sysinit, &ident ## _vnet_init)
 348
 349 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 350         CTASSERT((subsystem) > SI_SUB_VNET &&                           \
 351             (subsystem) <= SI_SUB_VNET_DONE);                           \
 352         static struct vnet_sysinit ident ## _vnet_uninit = {            \
 353                 subsystem,                                              \
 354                 order,                                                  \
 355                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 356                 (arg)                                                   \
 357         };                                                              \
 358         SYSINIT(vnet_uninit_ ## ident, subsystem, order,                \
 359             vnet_register_sysuninit, &ident ## _vnet_uninit);           \
 360         SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,              \
 361             vnet_deregister_sysuninit, &ident ## _vnet_uninit)
 362
 363 /*
 364  * Interfaces for managing per-vnet constructors and destructors.
 365  */
 366 void    vnet_register_sysinit(void *arg);
 367 void    vnet_register_sysuninit(void *arg);
 368 void    vnet_deregister_sysinit(void *arg);
 369 void    vnet_deregister_sysuninit(void *arg);
 370
 371 /*
 372  * EVENTHANDLER(9) extensions.
 373  */
 374 #include <sys/eventhandler.h>
 375
 376 void    vnet_global_eventhandler_iterator_func(void *, ...);
 377 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 378 do {                                                                    \
 379         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 380                 (tag) = vimage_eventhandler_register(NULL, #name, func, \
 381                     arg, priority,                                      \
 382                     vnet_global_eventhandler_iterator_func);            \
 383         }                                                               \
 384 } while(0)
 385 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 386 do {                                                                    \
 387         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 388                 vimage_eventhandler_register(NULL, #name, func,         \
 389                     arg, priority,                                      \
 390                     vnet_global_eventhandler_iterator_func);            \
 391         }                                                               \
 392 } while(0)
 393
 394 #else /* !VIMAGE */
 395
 396 /*
 397  * Various virtual network stack macros compile to no-ops without VIMAGE.
 398  */
 399 #define curvnet                 NULL
 400
 401 #define VNET_ASSERT(exp, msg)
 402 #define CURVNET_SET(arg)
 403 #define CURVNET_SET_QUIET(arg)
 404 #define CURVNET_RESTORE()
 405 #define CURVNET_ASSERT_SET()                                            \
 406
 407 #define VNET_LIST_RLOCK()
 408 #define VNET_LIST_RLOCK_NOSLEEP()
 409 #define VNET_LIST_RUNLOCK()
 410 #define VNET_LIST_RUNLOCK_NOSLEEP()
 411 #define VNET_ITERATOR_DECL(arg)
 412 #define VNET_FOREACH(arg)       for (int _vn = 0; _vn == 0; _vn++)
 413
 414 #define IS_DEFAULT_VNET(arg)    1
 415 #define CRED_TO_VNET(cr)        NULL
 416 #define TD_TO_VNET(td)          NULL
 417 #define P_TO_VNET(p)            NULL
 418
 419 /*
 420  * Versions of the VNET macros that compile to normal global variables and
 421  * standard sysctl definitions.
 422  */
 423 #define VNET_NAME(n)            n
 424 #define VNET_DECLARE(t, n)      extern t n
 425 #define VNET_DEFINE(t, n)       struct _hack; t n
 426 #define VNET_DEFINE_STATIC(t, n)        static t n
 427 #define _VNET_PTR(b, n)         &VNET_NAME(n)
 428
 429 /*
 430  * Virtualized global variable accessor macros.
 431  */
 432 #define VNET_VNET_PTR(vnet, n)          (&(n))
 433 #define VNET_VNET(vnet, n)              (n)
 434
 435 #define VNET_PTR(n)             (&(n))
 436 #define VNET(n)                 (n)
 437
 438 /*
 439  * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
 440  * map into normal sysinits, which have the same ordering properties.
 441  */
 442 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 443         SYSINIT(ident, subsystem, order, func, arg)
 444 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 445         SYSUNINIT(ident, subsystem, order, func, arg)
 446
 447 /*
 448  * Without VIMAGE revert to the default implementation.
 449  */
 450 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 451         (tag) = eventhandler_register(NULL, #name, func, arg, priority)
 452 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 453         eventhandler_register(NULL, #name, func, arg, priority)
 454 #endif /* VIMAGE */
 455 #endif /* _KERNEL */
 456
 457 #endif /* !_NET_VNET_H_ */