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         bool                     vnet_shutdown; /* Shutdown in progress. */
  79 } __aligned(CACHE_LINE_SIZE);
  80 #define VNET_MAGIC_N    0x5e4a6f28
  81
  82 /*
  83  * These two virtual network stack allocator definitions are also required
  84  * for libkvm so that it can evaluate virtualized global variables.
  85  */
  86 #define VNET_SETNAME            "set_vnet"
  87 #define VNET_SYMPREFIX          "vnet_entry_"
  88 #endif
  89
  90 #ifdef _KERNEL
  91
  92 #define VNET_PCPUSTAT_DECLARE(type, name)       \
  93     VNET_DECLARE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  94
  95 #define VNET_PCPUSTAT_DEFINE(type, name)        \
  96     VNET_DEFINE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  97 #define VNET_PCPUSTAT_DEFINE_STATIC(type, name) \
  98     VNET_DEFINE_STATIC(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  99
 100 #define VNET_PCPUSTAT_ALLOC(name, wait) \
 101     COUNTER_ARRAY_ALLOC(VNET(name), \
 102         sizeof(VNET(name)) / sizeof(counter_u64_t), (wait))
 103
 104 #define VNET_PCPUSTAT_FREE(name)        \
 105     COUNTER_ARRAY_FREE(VNET(name), sizeof(VNET(name)) / sizeof(counter_u64_t))
 106
 107 #define VNET_PCPUSTAT_ADD(type, name, f, v)     \
 108     counter_u64_add(VNET(name)[offsetof(type, f) / sizeof(uint64_t)], (v))
 109
 110 #define VNET_PCPUSTAT_FETCH(type, name, f)      \
 111     counter_u64_fetch(VNET(name)[offsetof(type, f) / sizeof(uint64_t)])
 112
 113 #define VNET_PCPUSTAT_SYSINIT(name)     \
 114 static void                             \
 115 vnet_##name##_init(const void *unused)  \
 116 {                                       \
 117         VNET_PCPUSTAT_ALLOC(name, M_WAITOK);    \
 118 }                                       \
 119 VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_INIT_IF,                    \
 120     SI_ORDER_FIRST, vnet_ ## name ## _init, NULL)
 121
 122 #define VNET_PCPUSTAT_SYSUNINIT(name)                                   \
 123 static void                                                             \
 124 vnet_##name##_uninit(const void *unused)                                \
 125 {                                                                       \
 126         VNET_PCPUSTAT_FREE(name);                                       \
 127 }                                                                       \
 128 VNET_SYSUNINIT(vnet_ ## name ## _uninit, SI_SUB_INIT_IF,                \
 129     SI_ORDER_FIRST, vnet_ ## name ## _uninit, NULL)
 130
 131 #ifdef SYSCTL_OID
 132 #define SYSCTL_VNET_PCPUSTAT(parent, nbr, name, type, array, desc)      \
 133 static int                                                              \
 134 array##_sysctl(SYSCTL_HANDLER_ARGS)                                     \
 135 {                                                                       \
 136         type s;                                                         \
 137         CTASSERT((sizeof(type) / sizeof(uint64_t)) ==                   \
 138             (sizeof(VNET(array)) / sizeof(counter_u64_t)));             \
 139         COUNTER_ARRAY_COPY(VNET(array), &s, sizeof(type) / sizeof(uint64_t));\
 140         if (req->newptr)                                                \
 141                 COUNTER_ARRAY_ZERO(VNET(array),                         \
 142                     sizeof(type) / sizeof(uint64_t));                   \
 143         return (SYSCTL_OUT(req, &s, sizeof(type)));                     \
 144 }                                                                       \
 145 SYSCTL_PROC(parent, nbr, name,                                          \
 146     CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_NEEDGIANT,     \
 147     NULL, 0, array ## _sysctl, "I", desc)
 148 #endif /* SYSCTL_OID */
 149
 150 #ifdef VIMAGE
 151 #include <sys/lock.h>
 152 #include <sys/proc.h>                   /* for struct thread */
 153 #include <sys/rwlock.h>
 154 #include <sys/sx.h>
 155
 156 /*
 157  * Location of the kernel's 'set_vnet' linker set.
 158  */
 159 extern uintptr_t        *__start_set_vnet;
 160 __GLOBL(__start_set_vnet);
 161 extern uintptr_t        *__stop_set_vnet;
 162 __GLOBL(__stop_set_vnet);
 163
 164 #define VNET_START      (uintptr_t)&__start_set_vnet
 165 #define VNET_STOP       (uintptr_t)&__stop_set_vnet
 166
 167 /*
 168  * Functions to allocate and destroy virtual network stacks.
 169  */
 170 struct vnet *vnet_alloc(void);
 171 void    vnet_destroy(struct vnet *vnet);
 172
 173 /*
 174  * The current virtual network stack -- we may wish to move this to struct
 175  * pcpu in the future.
 176  */
 177 #define curvnet curthread->td_vnet
 178
 179 /*
 180  * Various macros -- get and set the current network stack, but also
 181  * assertions.
 182  */
 183 #if defined(INVARIANTS) || defined(VNET_DEBUG)
 184 #define VNET_ASSERT(exp, msg)   do {                                    \
 185         if (!(exp))                                                     \
 186                 panic msg;                                              \
 187 } while (0)
 188 #else
 189 #define VNET_ASSERT(exp, msg)   do {                                    \
 190 } while (0)
 191 #endif
 192
 193 #ifdef VNET_DEBUG
 194 void vnet_log_recursion(struct vnet *, const char *, int);
 195
 196 #define CURVNET_SET_QUIET(arg)                                          \
 197         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 198             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 199             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 200         struct vnet *saved_vnet = curvnet;                              \
 201         const char *saved_vnet_lpush = curthread->td_vnet_lpush;        \
 202         curvnet = arg;                                                  \
 203         curthread->td_vnet_lpush = __func__;
 204
 205 #define CURVNET_SET_VERBOSE(arg)                                        \
 206         CURVNET_SET_QUIET(arg)                                          \
 207         if (saved_vnet)                                                 \
 208                 vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
 209
 210 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 211
 212 #define CURVNET_RESTORE()                                               \
 213         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 214             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 215             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 216             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 217         curvnet = saved_vnet;                                           \
 218         curthread->td_vnet_lpush = saved_vnet_lpush;
 219 #else /* !VNET_DEBUG */
 220
 221 #define CURVNET_SET_QUIET(arg)                                          \
 222         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 223             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 224             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 225         struct vnet *saved_vnet = curvnet;                              \
 226         curvnet = arg;
 227
 228 #define CURVNET_SET_VERBOSE(arg)                                        \
 229         CURVNET_SET_QUIET(arg)
 230
 231 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 232
 233 #define CURVNET_RESTORE()                                               \
 234         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 235             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 236             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 237             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 238         curvnet = saved_vnet;
 239 #endif /* VNET_DEBUG */
 240
 241 #define CURVNET_ASSERT_SET()                                            \
 242         VNET_ASSERT(curvnet != NULL, ("vnet is not set at %s:%d %s()",  \
 243             __FILE__, __LINE__, __func__))
 244
 245 extern struct vnet *vnet0;
 246 #define IS_DEFAULT_VNET(arg)    ((arg) == vnet0)
 247
 248 #define CRED_TO_VNET(cr)        (cr)->cr_prison->pr_vnet
 249 #define TD_TO_VNET(td)          CRED_TO_VNET((td)->td_ucred)
 250 #define P_TO_VNET(p)            CRED_TO_VNET((p)->p_ucred)
 251
 252 /*
 253  * Global linked list of all virtual network stacks, along with read locks to
 254  * access it.  If a caller may sleep while accessing the list, it must use
 255  * the sleepable lock macros.
 256  */
 257 LIST_HEAD(vnet_list_head, vnet);
 258 extern struct vnet_list_head vnet_head;
 259 extern struct rwlock vnet_rwlock;
 260 extern struct sx vnet_sxlock;
 261
 262 #define VNET_LIST_RLOCK()               sx_slock(&vnet_sxlock)
 263 #define VNET_LIST_RLOCK_NOSLEEP()       rw_rlock(&vnet_rwlock)
 264 #define VNET_LIST_RUNLOCK()             sx_sunlock(&vnet_sxlock)
 265 #define VNET_LIST_RUNLOCK_NOSLEEP()     rw_runlock(&vnet_rwlock)
 266
 267 /*
 268  * Iteration macros to walk the global list of virtual network stacks.
 269  */
 270 #define VNET_ITERATOR_DECL(arg) struct vnet *arg
 271 #define VNET_FOREACH(arg)       LIST_FOREACH((arg), &vnet_head, vnet_le)
 272
 273 /*
 274  * Virtual network stack memory allocator, which allows global variables to
 275  * be automatically instantiated for each network stack instance.
 276  */
 277 #define VNET_NAME(n)            vnet_entry_##n
 278 #define VNET_DECLARE(t, n)      extern t VNET_NAME(n)
 279 /* struct _hack is to stop this from being used with static data */
 280 #define VNET_DEFINE(t, n)       \
 281     struct _hack; t VNET_NAME(n) __section(VNET_SETNAME) __used
 282 #if defined(KLD_MODULE) && (defined(__aarch64__) || defined(__riscv) \
 283                 || defined(__powerpc64__))
 284 /*
 285  * As with DPCPU_DEFINE_STATIC we are unable to mark this data as static
 286  * in modules on some architectures.
 287  */
 288 #define VNET_DEFINE_STATIC(t, n) \
 289     t VNET_NAME(n) __section(VNET_SETNAME) __used
 290 #else
 291 #define VNET_DEFINE_STATIC(t, n) \
 292     static t VNET_NAME(n) __section(VNET_SETNAME) __used
 293 #endif
 294 #define _VNET_PTR(b, n)         (__typeof(VNET_NAME(n))*)               \
 295                                     ((b) + (uintptr_t)&VNET_NAME(n))
 296
 297 #define _VNET(b, n)             (*_VNET_PTR(b, n))
 298
 299 /*
 300  * Virtualized global variable accessor macros.
 301  */
 302 #define VNET_VNET_PTR(vnet, n)          _VNET_PTR((vnet)->vnet_data_base, n)
 303 #define VNET_VNET(vnet, n)              (*VNET_VNET_PTR((vnet), n))
 304
 305 #define VNET_PTR(n)             VNET_VNET_PTR(curvnet, n)
 306 #define VNET(n)                 VNET_VNET(curvnet, n)
 307
 308 /*
 309  * Virtual network stack allocator interfaces from the kernel linker.
 310  */
 311 void    *vnet_data_alloc(int size);
 312 void     vnet_data_copy(void *start, int size);
 313 void     vnet_data_free(void *start_arg, int size);
 314
 315 /*
 316  * Virtual sysinit mechanism, allowing network stack components to declare
 317  * startup and shutdown methods to be run when virtual network stack
 318  * instances are created and destroyed.
 319  */
 320 #include <sys/kernel.h>
 321
 322 /*
 323  * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
 324  * destructors.
 325  */
 326 struct vnet_sysinit {
 327         enum sysinit_sub_id     subsystem;
 328         enum sysinit_elem_order order;
 329         sysinit_cfunc_t         func;
 330         const void              *arg;
 331         TAILQ_ENTRY(vnet_sysinit) link;
 332 };
 333
 334 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 335         CTASSERT((subsystem) > SI_SUB_VNET &&                           \
 336             (subsystem) <= SI_SUB_VNET_DONE);                           \
 337         static struct vnet_sysinit ident ## _vnet_init = {              \
 338                 subsystem,                                              \
 339                 order,                                                  \
 340                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 341                 (arg)                                                   \
 342         };                                                              \
 343         SYSINIT(vnet_init_ ## ident, subsystem, order,                  \
 344             vnet_register_sysinit, &ident ## _vnet_init);               \
 345         SYSUNINIT(vnet_init_ ## ident, subsystem, order,                \
 346             vnet_deregister_sysinit, &ident ## _vnet_init)
 347
 348 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 349         CTASSERT((subsystem) > SI_SUB_VNET &&                           \
 350             (subsystem) <= SI_SUB_VNET_DONE);                           \
 351         static struct vnet_sysinit ident ## _vnet_uninit = {            \
 352                 subsystem,                                              \
 353                 order,                                                  \
 354                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 355                 (arg)                                                   \
 356         };                                                              \
 357         SYSINIT(vnet_uninit_ ## ident, subsystem, order,                \
 358             vnet_register_sysuninit, &ident ## _vnet_uninit);           \
 359         SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,              \
 360             vnet_deregister_sysuninit, &ident ## _vnet_uninit)
 361
 362 /*
 363  * Run per-vnet sysinits or sysuninits during vnet creation/destruction.
 364  */
 365 void     vnet_sysinit(void);
 366 void     vnet_sysuninit(void);
 367
 368 /*
 369  * Interfaces for managing per-vnet constructors and destructors.
 370  */
 371 void    vnet_register_sysinit(void *arg);
 372 void    vnet_register_sysuninit(void *arg);
 373 void    vnet_deregister_sysinit(void *arg);
 374 void    vnet_deregister_sysuninit(void *arg);
 375
 376 /*
 377  * EVENTHANDLER(9) extensions.
 378  */
 379 #include <sys/eventhandler.h>
 380
 381 void    vnet_global_eventhandler_iterator_func(void *, ...);
 382 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 383 do {                                                                    \
 384         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 385                 (tag) = vimage_eventhandler_register(NULL, #name, func, \
 386                     arg, priority,                                      \
 387                     vnet_global_eventhandler_iterator_func);            \
 388         }                                                               \
 389 } while(0)
 390 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 391 do {                                                                    \
 392         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 393                 vimage_eventhandler_register(NULL, #name, func,         \
 394                     arg, priority,                                      \
 395                     vnet_global_eventhandler_iterator_func);            \
 396         }                                                               \
 397 } while(0)
 398
 399 #else /* !VIMAGE */
 400
 401 /*
 402  * Various virtual network stack macros compile to no-ops without VIMAGE.
 403  */
 404 #define curvnet                 NULL
 405
 406 #define VNET_ASSERT(exp, msg)
 407 #define CURVNET_SET(arg)
 408 #define CURVNET_SET_QUIET(arg)
 409 #define CURVNET_RESTORE()
 410 #define CURVNET_ASSERT_SET()                                            \
 411
 412 #define VNET_LIST_RLOCK()
 413 #define VNET_LIST_RLOCK_NOSLEEP()
 414 #define VNET_LIST_RUNLOCK()
 415 #define VNET_LIST_RUNLOCK_NOSLEEP()
 416 #define VNET_ITERATOR_DECL(arg)
 417 #define VNET_FOREACH(arg)
 418
 419 #define IS_DEFAULT_VNET(arg)    1
 420 #define CRED_TO_VNET(cr)        NULL
 421 #define TD_TO_VNET(td)          NULL
 422 #define P_TO_VNET(p)            NULL
 423
 424 /*
 425  * Versions of the VNET macros that compile to normal global variables and
 426  * standard sysctl definitions.
 427  */
 428 #define VNET_NAME(n)            n
 429 #define VNET_DECLARE(t, n)      extern t n
 430 #define VNET_DEFINE(t, n)       struct _hack; t n
 431 #define VNET_DEFINE_STATIC(t, n)        static t n
 432 #define _VNET_PTR(b, n)         &VNET_NAME(n)
 433
 434 /*
 435  * Virtualized global variable accessor macros.
 436  */
 437 #define VNET_VNET_PTR(vnet, n)          (&(n))
 438 #define VNET_VNET(vnet, n)              (n)
 439
 440 #define VNET_PTR(n)             (&(n))
 441 #define VNET(n)                 (n)
 442
 443 /*
 444  * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
 445  * map into normal sysinits, which have the same ordering properties.
 446  */
 447 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 448         SYSINIT(ident, subsystem, order, func, arg)
 449 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 450         SYSUNINIT(ident, subsystem, order, func, arg)
 451
 452 /*
 453  * Without VIMAGE revert to the default implementation.
 454  */
 455 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 456         (tag) = eventhandler_register(NULL, #name, func, arg, priority)
 457 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 458         eventhandler_register(NULL, #name, func, arg, priority)
 459 #endif /* VIMAGE */
 460 #endif /* _KERNEL */
 461
 462 #endif /* !_NET_VNET_H_ */