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