sys/net/vnet.h

   1 /*-
   2  * Copyright (c) 2006-2009 University of Zagreb
   3  * Copyright (c) 2006-2009 FreeBSD Foundation
   4  * All rights reserved.
   5  *
   6  * This software was developed by the University of Zagreb and the
   7  * FreeBSD Foundation under sponsorship by the Stichting NLnet and the
   8  * FreeBSD Foundation.
   9  *
  10  * Copyright (c) 2009 Jeffrey Roberson <jeff@freebsd.org>
  11  * Copyright (c) 2009 Robert N. M. Watson
  12  * All rights reserved.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * $FreeBSD$
  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 <sys/queue.h>
  67
  68 struct vnet {
  69         LIST_ENTRY(vnet)         vnet_le;       /* all vnets list */
  70         u_int                    vnet_magic_n;
  71         u_int                    vnet_ifcnt;
  72         u_int                    vnet_sockcnt;
  73         void                    *vnet_data_mem;
  74         uintptr_t                vnet_data_base;
  75 };
  76 #define VNET_MAGIC_N    0x3e0d8f29
  77
  78 /*
  79  * These two virtual network stack allocator definitions are also required
  80  * for libkvm so that it can evaluate virtualized global variables.
  81  */
  82 #define VNET_SETNAME            "set_vnet"
  83 #define VNET_SYMPREFIX          "vnet_entry_"
  84 #endif
  85
  86 #ifdef _KERNEL
  87
  88 #define VNET_PCPUSTAT_DECLARE(type, name)       \
  89     VNET_DECLARE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  90
  91 #define VNET_PCPUSTAT_DEFINE(type, name)        \
  92     VNET_DEFINE(counter_u64_t, name[sizeof(type) / sizeof(uint64_t)])
  93
  94 #define VNET_PCPUSTAT_ALLOC(name, wait) \
  95     COUNTER_ARRAY_ALLOC(VNET(name), \
  96         sizeof(VNET(name)) / sizeof(counter_u64_t), (wait))
  97
  98 #define VNET_PCPUSTAT_FREE(name)        \
  99     COUNTER_ARRAY_FREE(VNET(name), sizeof(VNET(name)) / sizeof(counter_u64_t))
 100
 101 #define VNET_PCPUSTAT_ADD(type, name, f, v)     \
 102     counter_u64_add(VNET(name)[offsetof(type, f) / sizeof(uint64_t)], (v))
 103
 104 #define VNET_PCPUSTAT_FETCH(type, name, f)      \
 105     counter_u64_fetch(VNET(name)[offsetof(type, f) / sizeof(uint64_t)])
 106
 107 #define VNET_PCPUSTAT_SYSINIT(name)     \
 108 static void                             \
 109 vnet_##name##_init(const void *unused)  \
 110 {                                       \
 111         VNET_PCPUSTAT_ALLOC(name, M_WAITOK);    \
 112 }                                       \
 113 VNET_SYSINIT(vnet_ ## name ## _init, SI_SUB_PROTO_IFATTACHDOMAIN,       \
 114     SI_ORDER_ANY, vnet_ ## name ## _init, NULL)
 115
 116 #define VNET_PCPUSTAT_SYSUNINIT(name)                                   \
 117 static void                                                             \
 118 vnet_##name##_uninit(const void *unused)                                \
 119 {                                                                       \
 120         VNET_PCPUSTAT_FREE(name);                                       \
 121 }                                                                       \
 122 VNET_SYSUNINIT(vnet_ ## name ## _uninit, SI_SUB_PROTO_IFATTACHDOMAIN,   \
 123     SI_ORDER_ANY, vnet_ ## name ## _uninit, NULL)
 124
 125 #ifdef SYSCTL_OID
 126 #define SYSCTL_VNET_PCPUSTAT(parent, nbr, name, type, array, desc)      \
 127 static int                                                              \
 128 array##_sysctl(SYSCTL_HANDLER_ARGS)                                     \
 129 {                                                                       \
 130         type s;                                                         \
 131         CTASSERT((sizeof(type) / sizeof(uint64_t)) ==                   \
 132             (sizeof(VNET(array)) / sizeof(counter_u64_t)));             \
 133         COUNTER_ARRAY_COPY(VNET(array), &s, sizeof(type) / sizeof(uint64_t));\
 134         if (req->newptr)                                                \
 135                 COUNTER_ARRAY_ZERO(VNET(array),                         \
 136                     sizeof(type) / sizeof(uint64_t));                   \
 137         return (SYSCTL_OUT(req, &s, sizeof(type)));                     \
 138 }                                                                       \
 139 SYSCTL_PROC(parent, nbr, name, CTLFLAG_VNET | CTLTYPE_OPAQUE | CTLFLAG_RW, \
 140     NULL, 0, array ## _sysctl, "I", desc)
 141 #endif /* SYSCTL_OID */
 142
 143 #ifdef VIMAGE
 144 #include <sys/lock.h>
 145 #include <sys/proc.h>                   /* for struct thread */
 146 #include <sys/rwlock.h>
 147 #include <sys/sx.h>
 148
 149 /*
 150  * Location of the kernel's 'set_vnet' linker set.
 151  */
 152 extern uintptr_t        *__start_set_vnet;
 153 __GLOBL(__start_set_vnet);
 154 extern uintptr_t        *__stop_set_vnet;
 155 __GLOBL(__stop_set_vnet);
 156
 157 #define VNET_START      (uintptr_t)&__start_set_vnet
 158 #define VNET_STOP       (uintptr_t)&__stop_set_vnet
 159
 160 /*
 161  * Functions to allocate and destroy virtual network stacks.
 162  */
 163 struct vnet *vnet_alloc(void);
 164 void    vnet_destroy(struct vnet *vnet);
 165
 166 /*
 167  * The current virtual network stack -- we may wish to move this to struct
 168  * pcpu in the future.
 169  */
 170 #define curvnet curthread->td_vnet
 171
 172 /*
 173  * Various macros -- get and set the current network stack, but also
 174  * assertions.
 175  */
 176 #if defined(INVARIANTS) || defined(VNET_DEBUG)
 177 #define VNET_ASSERT(exp, msg)   do {                                    \
 178         if (!(exp))                                                     \
 179                 panic msg;                                              \
 180 } while (0)
 181 #else
 182 #define VNET_ASSERT(exp, msg)   do {                                    \
 183 } while (0)
 184 #endif
 185
 186 #ifdef VNET_DEBUG
 187 void vnet_log_recursion(struct vnet *, const char *, int);
 188
 189 #define CURVNET_SET_QUIET(arg)                                          \
 190         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 191             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 192             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 193         struct vnet *saved_vnet = curvnet;                              \
 194         const char *saved_vnet_lpush = curthread->td_vnet_lpush;        \
 195         curvnet = arg;                                                  \
 196         curthread->td_vnet_lpush = __func__;
 197
 198 #define CURVNET_SET_VERBOSE(arg)                                        \
 199         CURVNET_SET_QUIET(arg)                                          \
 200         if (saved_vnet)                                                 \
 201                 vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
 202
 203 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 204
 205 #define CURVNET_RESTORE()                                               \
 206         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 207             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 208             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 209             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 210         curvnet = saved_vnet;                                           \
 211         curthread->td_vnet_lpush = saved_vnet_lpush;
 212 #else /* !VNET_DEBUG */
 213
 214 #define CURVNET_SET_QUIET(arg)                                          \
 215         VNET_ASSERT((arg) != NULL && (arg)->vnet_magic_n == VNET_MAGIC_N, \
 216             ("CURVNET_SET at %s:%d %s() curvnet=%p vnet=%p",            \
 217             __FILE__, __LINE__, __func__, curvnet, (arg)));             \
 218         struct vnet *saved_vnet = curvnet;                              \
 219         curvnet = arg;
 220
 221 #define CURVNET_SET_VERBOSE(arg)                                        \
 222         CURVNET_SET_QUIET(arg)
 223
 224 #define CURVNET_SET(arg)        CURVNET_SET_VERBOSE(arg)
 225
 226 #define CURVNET_RESTORE()                                               \
 227         VNET_ASSERT(curvnet != NULL && (saved_vnet == NULL ||           \
 228             saved_vnet->vnet_magic_n == VNET_MAGIC_N),                  \
 229             ("CURVNET_RESTORE at %s:%d %s() curvnet=%p saved_vnet=%p",  \
 230             __FILE__, __LINE__, __func__, curvnet, saved_vnet));        \
 231         curvnet = saved_vnet;
 232 #endif /* VNET_DEBUG */
 233
 234 extern struct vnet *vnet0;
 235 #define IS_DEFAULT_VNET(arg)    ((arg) == vnet0)
 236
 237 #define CRED_TO_VNET(cr)        (cr)->cr_prison->pr_vnet
 238 #define TD_TO_VNET(td)          CRED_TO_VNET((td)->td_ucred)
 239 #define P_TO_VNET(p)            CRED_TO_VNET((p)->p_ucred)
 240
 241 /*
 242  * Global linked list of all virtual network stacks, along with read locks to
 243  * access it.  If a caller may sleep while accessing the list, it must use
 244  * the sleepable lock macros.
 245  */
 246 LIST_HEAD(vnet_list_head, vnet);
 247 extern struct vnet_list_head vnet_head;
 248 extern struct rwlock vnet_rwlock;
 249 extern struct sx vnet_sxlock;
 250
 251 #define VNET_LIST_RLOCK()               sx_slock(&vnet_sxlock)
 252 #define VNET_LIST_RLOCK_NOSLEEP()       rw_rlock(&vnet_rwlock)
 253 #define VNET_LIST_RUNLOCK()             sx_sunlock(&vnet_sxlock)
 254 #define VNET_LIST_RUNLOCK_NOSLEEP()     rw_runlock(&vnet_rwlock)
 255
 256 /*
 257  * Iteration macros to walk the global list of virtual network stacks.
 258  */
 259 #define VNET_ITERATOR_DECL(arg) struct vnet *arg
 260 #define VNET_FOREACH(arg)       LIST_FOREACH((arg), &vnet_head, vnet_le)
 261
 262 /*
 263  * Virtual network stack memory allocator, which allows global variables to
 264  * be automatically instantiated for each network stack instance.
 265  */
 266 #define VNET_NAME(n)            vnet_entry_##n
 267 #define VNET_DECLARE(t, n)      extern t VNET_NAME(n)
 268 #define VNET_DEFINE(t, n)       t VNET_NAME(n) __section(VNET_SETNAME) __used
 269 #define _VNET_PTR(b, n)         (__typeof(VNET_NAME(n))*)               \
 270                                     ((b) + (uintptr_t)&VNET_NAME(n))
 271
 272 #define _VNET(b, n)             (*_VNET_PTR(b, n))
 273
 274 /*
 275  * Virtualized global variable accessor macros.
 276  */
 277 #define VNET_VNET_PTR(vnet, n)          _VNET_PTR((vnet)->vnet_data_base, n)
 278 #define VNET_VNET(vnet, n)              (*VNET_VNET_PTR((vnet), n))
 279
 280 #define VNET_PTR(n)             VNET_VNET_PTR(curvnet, n)
 281 #define VNET(n)                 VNET_VNET(curvnet, n)
 282
 283 /*
 284  * Virtual network stack allocator interfaces from the kernel linker.
 285  */
 286 void    *vnet_data_alloc(int size);
 287 void     vnet_data_copy(void *start, int size);
 288 void     vnet_data_free(void *start_arg, int size);
 289
 290 /*
 291  * Virtual sysinit mechanism, allowing network stack components to declare
 292  * startup and shutdown methods to be run when virtual network stack
 293  * instances are created and destroyed.
 294  */
 295 #include <sys/kernel.h>
 296
 297 /*
 298  * SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
 299  * destructors.
 300  */
 301 struct vnet_sysinit {
 302         enum sysinit_sub_id     subsystem;
 303         enum sysinit_elem_order order;
 304         sysinit_cfunc_t         func;
 305         const void              *arg;
 306         TAILQ_ENTRY(vnet_sysinit) link;
 307 };
 308
 309 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 310         static struct vnet_sysinit ident ## _vnet_init = {              \
 311                 subsystem,                                              \
 312                 order,                                                  \
 313                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 314                 (arg)                                                   \
 315         };                                                              \
 316         SYSINIT(vnet_init_ ## ident, subsystem, order,                  \
 317             vnet_register_sysinit, &ident ## _vnet_init);               \
 318         SYSUNINIT(vnet_init_ ## ident, subsystem, order,                \
 319             vnet_deregister_sysinit, &ident ## _vnet_init)
 320
 321 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 322         static struct vnet_sysinit ident ## _vnet_uninit = {            \
 323                 subsystem,                                              \
 324                 order,                                                  \
 325                 (sysinit_cfunc_t)(sysinit_nfunc_t)func,                 \
 326                 (arg)                                                   \
 327         };                                                              \
 328         SYSINIT(vnet_uninit_ ## ident, subsystem, order,                \
 329             vnet_register_sysuninit, &ident ## _vnet_uninit);           \
 330         SYSUNINIT(vnet_uninit_ ## ident, subsystem, order,              \
 331             vnet_deregister_sysuninit, &ident ## _vnet_uninit)
 332
 333 /*
 334  * Run per-vnet sysinits or sysuninits during vnet creation/destruction.
 335  */
 336 void     vnet_sysinit(void);
 337 void     vnet_sysuninit(void);
 338
 339 /*
 340  * Interfaces for managing per-vnet constructors and destructors.
 341  */
 342 void    vnet_register_sysinit(void *arg);
 343 void    vnet_register_sysuninit(void *arg);
 344 void    vnet_deregister_sysinit(void *arg);
 345 void    vnet_deregister_sysuninit(void *arg);
 346
 347 /*
 348  * EVENTHANDLER(9) extensions.
 349  */
 350 #include <sys/eventhandler.h>
 351
 352 void    vnet_global_eventhandler_iterator_func(void *, ...);
 353 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 354 do {                                                                    \
 355         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 356                 (tag) = vimage_eventhandler_register(NULL, #name, func, \
 357                     arg, priority,                                      \
 358                     vnet_global_eventhandler_iterator_func);            \
 359         }                                                               \
 360 } while(0)
 361 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 362 do {                                                                    \
 363         if (IS_DEFAULT_VNET(curvnet)) {                                 \
 364                 vimage_eventhandler_register(NULL, #name, func,         \
 365                     arg, priority,                                      \
 366                     vnet_global_eventhandler_iterator_func);            \
 367         }                                                               \
 368 } while(0)
 369
 370 #else /* !VIMAGE */
 371
 372 /*
 373  * Various virtual network stack macros compile to no-ops without VIMAGE.
 374  */
 375 #define curvnet                 NULL
 376
 377 #define VNET_ASSERT(exp, msg)
 378 #define CURVNET_SET(arg)
 379 #define CURVNET_SET_QUIET(arg)
 380 #define CURVNET_RESTORE()
 381
 382 #define VNET_LIST_RLOCK()
 383 #define VNET_LIST_RLOCK_NOSLEEP()
 384 #define VNET_LIST_RUNLOCK()
 385 #define VNET_LIST_RUNLOCK_NOSLEEP()
 386 #define VNET_ITERATOR_DECL(arg)
 387 #define VNET_FOREACH(arg)
 388
 389 #define IS_DEFAULT_VNET(arg)    1
 390 #define CRED_TO_VNET(cr)        NULL
 391 #define TD_TO_VNET(td)          NULL
 392 #define P_TO_VNET(p)            NULL
 393
 394 /*
 395  * Versions of the VNET macros that compile to normal global variables and
 396  * standard sysctl definitions.
 397  */
 398 #define VNET_NAME(n)            n
 399 #define VNET_DECLARE(t, n)      extern t n
 400 #define VNET_DEFINE(t, n)       t n
 401 #define _VNET_PTR(b, n)         &VNET_NAME(n)
 402
 403 /*
 404  * Virtualized global variable accessor macros.
 405  */
 406 #define VNET_VNET_PTR(vnet, n)          (&(n))
 407 #define VNET_VNET(vnet, n)              (n)
 408
 409 #define VNET_PTR(n)             (&(n))
 410 #define VNET(n)                 (n)
 411
 412 /*
 413  * When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
 414  * map into normal sysinits, which have the same ordering properties.
 415  */
 416 #define VNET_SYSINIT(ident, subsystem, order, func, arg)                \
 417         SYSINIT(ident, subsystem, order, func, arg)
 418 #define VNET_SYSUNINIT(ident, subsystem, order, func, arg)              \
 419         SYSUNINIT(ident, subsystem, order, func, arg)
 420
 421 /*
 422  * Without VIMAGE revert to the default implementation.
 423  */
 424 #define VNET_GLOBAL_EVENTHANDLER_REGISTER_TAG(tag, name, func, arg, priority) \
 425         (tag) = eventhandler_register(NULL, #name, func, arg, priority)
 426 #define VNET_GLOBAL_EVENTHANDLER_REGISTER(name, func, arg, priority)    \
 427         eventhandler_register(NULL, #name, func, arg, priority)
 428 #endif /* VIMAGE */
 429 #endif /* _KERNEL */
 430
 431 #endif /* !_NET_VNET_H_ */