FreeBSD/Linux Kernel Cross Reference
sys/net/vnet.c
1 /*-
2 * Copyright (c) 2004-2009 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
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38
39 #include "opt_ddb.h"
40 #include "opt_kdb.h"
41 #include "opt_kdtrace.h"
42
43 #include <sys/param.h>
44 #include <sys/kdb.h>
45 #include <sys/kernel.h>
46 #include <sys/jail.h>
47 #include <sys/sdt.h>
48 #include <sys/systm.h>
49 #include <sys/sysctl.h>
50 #include <sys/eventhandler.h>
51 #include <sys/lock.h>
52 #include <sys/malloc.h>
53 #include <sys/proc.h>
54 #include <sys/socket.h>
55 #include <sys/sx.h>
56 #include <sys/sysctl.h>
57
58 #include <machine/stdarg.h>
59
60 #ifdef DDB
61 #include <ddb/ddb.h>
62 #include <ddb/db_sym.h>
63 #endif
64
65 #include <net/if.h>
66 #include <net/if_var.h>
67 #include <net/vnet.h>
68
69 /*-
70 * This file implements core functions for virtual network stacks:
71 *
72 * - Virtual network stack management functions.
73 *
74 * - Virtual network stack memory allocator, which virtualizes global
75 * variables in the network stack
76 *
77 * - Virtualized SYSINIT's/SYSUNINIT's, which allow network stack subsystems
78 * to register startup/shutdown events to be run for each virtual network
79 * stack instance.
80 */
81
82 FEATURE(vimage, "VIMAGE kernel virtualization");
83
84 MALLOC_DEFINE(M_VNET, "vnet", "network stack control block");
85
86 /*
87 * The virtual network stack list has two read-write locks, one sleepable and
88 * the other not, so that the list can be stablized and walked in a variety
89 * of network stack contexts. Both must be acquired exclusively to modify
90 * the list, but a read lock of either lock is sufficient to walk the list.
91 */
92 struct rwlock vnet_rwlock;
93 struct sx vnet_sxlock;
94
95 #define VNET_LIST_WLOCK() do { \
96 sx_xlock(&vnet_sxlock); \
97 rw_wlock(&vnet_rwlock); \
98 } while (0)
99
100 #define VNET_LIST_WUNLOCK() do { \
101 rw_wunlock(&vnet_rwlock); \
102 sx_xunlock(&vnet_sxlock); \
103 } while (0)
104
105 struct vnet_list_head vnet_head;
106 struct vnet *vnet0;
107
108 /*
109 * The virtual network stack allocator provides storage for virtualized
110 * global variables. These variables are defined/declared using the
111 * VNET_DEFINE()/VNET_DECLARE() macros, which place them in the 'set_vnet'
112 * linker set. The details of the implementation are somewhat subtle, but
113 * allow the majority of most network subsystems to maintain
114 * virtualization-agnostic.
115 *
116 * The virtual network stack allocator handles variables in the base kernel
117 * vs. modules in similar but different ways. In both cases, virtualized
118 * global variables are marked as such by being declared to be part of the
119 * vnet linker set. These "master" copies of global variables serve two
120 * functions:
121 *
122 * (1) They contain static initialization or "default" values for global
123 * variables which will be propagated to each virtual network stack
124 * instance when created. As with normal global variables, they default
125 * to zero-filled.
126 *
127 * (2) They act as unique global names by which the variable can be referred
128 * to, regardless of network stack instance. The single global symbol
129 * will be used to calculate the location of a per-virtual instance
130 * variable at run-time.
131 *
132 * Each virtual network stack instance has a complete copy of each
133 * virtualized global variable, stored in a malloc'd block of memory
134 * referred to by vnet->vnet_data_mem. Critical to the design is that each
135 * per-instance memory block is laid out identically to the master block so
136 * that the offset of each global variable is the same across all blocks. To
137 * optimize run-time access, a precalculated 'base' address,
138 * vnet->vnet_data_base, is stored in each vnet, and is the amount that can
139 * be added to the address of a 'master' instance of a variable to get to the
140 * per-vnet instance.
141 *
142 * Virtualized global variables are handled in a similar manner, but as each
143 * module has its own 'set_vnet' linker set, and we want to keep all
144 * virtualized globals togther, we reserve space in the kernel's linker set
145 * for potential module variables using a per-vnet character array,
146 * 'modspace'. The virtual network stack allocator maintains a free list to
147 * track what space in the array is free (all, initially) and as modules are
148 * linked, allocates portions of the space to specific globals. The kernel
149 * module linker queries the virtual network stack allocator and will
150 * bind references of the global to the location during linking. It also
151 * calls into the virtual network stack allocator, once the memory is
152 * initialized, in order to propagate the new static initializations to all
153 * existing virtual network stack instances so that the soon-to-be executing
154 * module will find every network stack instance with proper default values.
155 */
156
157 /*
158 * Number of bytes of data in the 'set_vnet' linker set, and hence the total
159 * size of all kernel virtualized global variables, and the malloc(9) type
160 * that will be used to allocate it.
161 */
162 #define VNET_BYTES (VNET_STOP - VNET_START)
163
164 MALLOC_DEFINE(M_VNET_DATA, "vnet_data", "VNET data");
165
166 /*
167 * VNET_MODMIN is the minimum number of bytes we will reserve for the sum of
168 * global variables across all loaded modules. As this actually sizes an
169 * array declared as a virtualized global variable in the kernel itself, and
170 * we want the virtualized global variable space to be page-sized, we may
171 * have more space than that in practice.
172 */
173 #define VNET_MODMIN 8192
174 #define VNET_SIZE roundup2(VNET_BYTES, PAGE_SIZE)
175 #define VNET_MODSIZE (VNET_SIZE - (VNET_BYTES - VNET_MODMIN))
176
177 /*
178 * Space to store virtualized global variables from loadable kernel modules,
179 * and the free list to manage it.
180 */
181 static VNET_DEFINE(char, modspace[VNET_MODMIN]);
182
183 /*
184 * Global lists of subsystem constructor and destructors for vnets. They are
185 * registered via VNET_SYSINIT() and VNET_SYSUNINIT(). Both lists are
186 * protected by the vnet_sysinit_sxlock global lock.
187 */
188 static TAILQ_HEAD(vnet_sysinit_head, vnet_sysinit) vnet_constructors =
189 TAILQ_HEAD_INITIALIZER(vnet_constructors);
190 static TAILQ_HEAD(vnet_sysuninit_head, vnet_sysinit) vnet_destructors =
191 TAILQ_HEAD_INITIALIZER(vnet_destructors);
192
193 struct sx vnet_sysinit_sxlock;
194
195 #define VNET_SYSINIT_WLOCK() sx_xlock(&vnet_sysinit_sxlock);
196 #define VNET_SYSINIT_WUNLOCK() sx_xunlock(&vnet_sysinit_sxlock);
197 #define VNET_SYSINIT_RLOCK() sx_slock(&vnet_sysinit_sxlock);
198 #define VNET_SYSINIT_RUNLOCK() sx_sunlock(&vnet_sysinit_sxlock);
199
200 struct vnet_data_free {
201 uintptr_t vnd_start;
202 int vnd_len;
203 TAILQ_ENTRY(vnet_data_free) vnd_link;
204 };
205
206 MALLOC_DEFINE(M_VNET_DATA_FREE, "vnet_data_free", "VNET resource accounting");
207 static TAILQ_HEAD(, vnet_data_free) vnet_data_free_head =
208 TAILQ_HEAD_INITIALIZER(vnet_data_free_head);
209 static struct sx vnet_data_free_lock;
210
211 SDT_PROVIDER_DEFINE(vnet);
212 SDT_PROBE_DEFINE1(vnet, functions, vnet_alloc, entry, entry, "int");
213 SDT_PROBE_DEFINE2(vnet, functions, vnet_alloc, alloc, alloc, "int",
214 "struct vnet *");
215 SDT_PROBE_DEFINE2(vnet, functions, vnet_alloc, return, return,
216 "int", "struct vnet *");
217 SDT_PROBE_DEFINE2(vnet, functions, vnet_destroy, entry, entry,
218 "int", "struct vnet *");
219 SDT_PROBE_DEFINE1(vnet, functions, vnet_destroy, return, entry,
220 "int");
221
222 #ifdef DDB
223 static void db_show_vnet_print_vs(struct vnet_sysinit *, int);
224 #endif
225
226 /*
227 * Allocate a virtual network stack.
228 */
229 struct vnet *
230 vnet_alloc(void)
231 {
232 struct vnet *vnet;
233
234 SDT_PROBE1(vnet, functions, vnet_alloc, entry, __LINE__);
235 vnet = malloc(sizeof(struct vnet), M_VNET, M_WAITOK | M_ZERO);
236 vnet->vnet_magic_n = VNET_MAGIC_N;
237 SDT_PROBE2(vnet, functions, vnet_alloc, alloc, __LINE__, vnet);
238
239 /*
240 * Allocate storage for virtualized global variables and copy in
241 * initial values form our 'master' copy.
242 */
243 vnet->vnet_data_mem = malloc(VNET_SIZE, M_VNET_DATA, M_WAITOK);
244 memcpy(vnet->vnet_data_mem, (void *)VNET_START, VNET_BYTES);
245
246 /*
247 * All use of vnet-specific data will immediately subtract VNET_START
248 * from the base memory pointer, so pre-calculate that now to avoid
249 * it on each use.
250 */
251 vnet->vnet_data_base = (uintptr_t)vnet->vnet_data_mem - VNET_START;
252
253 /* Initialize / attach vnet module instances. */
254 CURVNET_SET_QUIET(vnet);
255 vnet_sysinit();
256 CURVNET_RESTORE();
257
258 VNET_LIST_WLOCK();
259 LIST_INSERT_HEAD(&vnet_head, vnet, vnet_le);
260 VNET_LIST_WUNLOCK();
261
262 SDT_PROBE2(vnet, functions, vnet_alloc, return, __LINE__, vnet);
263 return (vnet);
264 }
265
266 /*
267 * Destroy a virtual network stack.
268 */
269 void
270 vnet_destroy(struct vnet *vnet)
271 {
272 struct ifnet *ifp, *nifp;
273
274 SDT_PROBE2(vnet, functions, vnet_destroy, entry, __LINE__, vnet);
275 KASSERT(vnet->vnet_sockcnt == 0,
276 ("%s: vnet still has sockets", __func__));
277
278 VNET_LIST_WLOCK();
279 LIST_REMOVE(vnet, vnet_le);
280 VNET_LIST_WUNLOCK();
281
282 CURVNET_SET_QUIET(vnet);
283
284 /* Return all inherited interfaces to their parent vnets. */
285 TAILQ_FOREACH_SAFE(ifp, &V_ifnet, if_link, nifp) {
286 if (ifp->if_home_vnet != ifp->if_vnet)
287 if_vmove(ifp, ifp->if_home_vnet);
288 }
289
290 vnet_sysuninit();
291 CURVNET_RESTORE();
292
293 /*
294 * Release storage for the virtual network stack instance.
295 */
296 free(vnet->vnet_data_mem, M_VNET_DATA);
297 vnet->vnet_data_mem = NULL;
298 vnet->vnet_data_base = 0;
299 vnet->vnet_magic_n = 0xdeadbeef;
300 free(vnet, M_VNET);
301 SDT_PROBE1(vnet, functions, vnet_destroy, return, __LINE__);
302 }
303
304 /*
305 * Boot time initialization and allocation of virtual network stacks.
306 */
307 static void
308 vnet_init_prelink(void *arg)
309 {
310
311 rw_init(&vnet_rwlock, "vnet_rwlock");
312 sx_init(&vnet_sxlock, "vnet_sxlock");
313 sx_init(&vnet_sysinit_sxlock, "vnet_sysinit_sxlock");
314 LIST_INIT(&vnet_head);
315 }
316 SYSINIT(vnet_init_prelink, SI_SUB_VNET_PRELINK, SI_ORDER_FIRST,
317 vnet_init_prelink, NULL);
318
319 static void
320 vnet0_init(void *arg)
321 {
322
323 /* Warn people before take off - in case we crash early. */
324 printf("WARNING: VIMAGE (virtualized network stack) is a highly "
325 "experimental feature.\n");
326
327 /*
328 * We MUST clear curvnet in vi_init_done() before going SMP,
329 * otherwise CURVNET_SET() macros would scream about unnecessary
330 * curvnet recursions.
331 */
332 curvnet = prison0.pr_vnet = vnet0 = vnet_alloc();
333 }
334 SYSINIT(vnet0_init, SI_SUB_VNET, SI_ORDER_FIRST, vnet0_init, NULL);
335
336 static void
337 vnet_init_done(void *unused)
338 {
339
340 curvnet = NULL;
341 }
342
343 SYSINIT(vnet_init_done, SI_SUB_VNET_DONE, SI_ORDER_FIRST, vnet_init_done,
344 NULL);
345
346 /*
347 * Once on boot, initialize the modspace freelist to entirely cover modspace.
348 */
349 static void
350 vnet_data_startup(void *dummy __unused)
351 {
352 struct vnet_data_free *df;
353
354 df = malloc(sizeof(*df), M_VNET_DATA_FREE, M_WAITOK | M_ZERO);
355 df->vnd_start = (uintptr_t)&VNET_NAME(modspace);
356 df->vnd_len = VNET_MODMIN;
357 TAILQ_INSERT_HEAD(&vnet_data_free_head, df, vnd_link);
358 sx_init(&vnet_data_free_lock, "vnet_data alloc lock");
359 }
360 SYSINIT(vnet_data, SI_SUB_KLD, SI_ORDER_FIRST, vnet_data_startup, 0);
361
362 /*
363 * When a module is loaded and requires storage for a virtualized global
364 * variable, allocate space from the modspace free list. This interface
365 * should be used only by the kernel linker.
366 */
367 void *
368 vnet_data_alloc(int size)
369 {
370 struct vnet_data_free *df;
371 void *s;
372
373 s = NULL;
374 size = roundup2(size, sizeof(void *));
375 sx_xlock(&vnet_data_free_lock);
376 TAILQ_FOREACH(df, &vnet_data_free_head, vnd_link) {
377 if (df->vnd_len < size)
378 continue;
379 if (df->vnd_len == size) {
380 s = (void *)df->vnd_start;
381 TAILQ_REMOVE(&vnet_data_free_head, df, vnd_link);
382 free(df, M_VNET_DATA_FREE);
383 break;
384 }
385 s = (void *)df->vnd_start;
386 df->vnd_len -= size;
387 df->vnd_start = df->vnd_start + size;
388 break;
389 }
390 sx_xunlock(&vnet_data_free_lock);
391
392 return (s);
393 }
394
395 /*
396 * Free space for a virtualized global variable on module unload.
397 */
398 void
399 vnet_data_free(void *start_arg, int size)
400 {
401 struct vnet_data_free *df;
402 struct vnet_data_free *dn;
403 uintptr_t start;
404 uintptr_t end;
405
406 size = roundup2(size, sizeof(void *));
407 start = (uintptr_t)start_arg;
408 end = start + size;
409 /*
410 * Free a region of space and merge it with as many neighbors as
411 * possible. Keeping the list sorted simplifies this operation.
412 */
413 sx_xlock(&vnet_data_free_lock);
414 TAILQ_FOREACH(df, &vnet_data_free_head, vnd_link) {
415 if (df->vnd_start > end)
416 break;
417 /*
418 * If we expand at the end of an entry we may have to merge
419 * it with the one following it as well.
420 */
421 if (df->vnd_start + df->vnd_len == start) {
422 df->vnd_len += size;
423 dn = TAILQ_NEXT(df, vnd_link);
424 if (df->vnd_start + df->vnd_len == dn->vnd_start) {
425 df->vnd_len += dn->vnd_len;
426 TAILQ_REMOVE(&vnet_data_free_head, dn,
427 vnd_link);
428 free(dn, M_VNET_DATA_FREE);
429 }
430 sx_xunlock(&vnet_data_free_lock);
431 return;
432 }
433 if (df->vnd_start == end) {
434 df->vnd_start = start;
435 df->vnd_len += size;
436 sx_xunlock(&vnet_data_free_lock);
437 return;
438 }
439 }
440 dn = malloc(sizeof(*df), M_VNET_DATA_FREE, M_WAITOK | M_ZERO);
441 dn->vnd_start = start;
442 dn->vnd_len = size;
443 if (df)
444 TAILQ_INSERT_BEFORE(df, dn, vnd_link);
445 else
446 TAILQ_INSERT_TAIL(&vnet_data_free_head, dn, vnd_link);
447 sx_xunlock(&vnet_data_free_lock);
448 }
449
450 /*
451 * When a new virtualized global variable has been allocated, propagate its
452 * initial value to each already-allocated virtual network stack instance.
453 */
454 void
455 vnet_data_copy(void *start, int size)
456 {
457 struct vnet *vnet;
458
459 VNET_LIST_RLOCK();
460 LIST_FOREACH(vnet, &vnet_head, vnet_le)
461 memcpy((void *)((uintptr_t)vnet->vnet_data_base +
462 (uintptr_t)start), start, size);
463 VNET_LIST_RUNLOCK();
464 }
465
466 /*
467 * Variants on sysctl_handle_foo that know how to handle virtualized global
468 * variables: if 'arg1' is a pointer, then we transform it to the local vnet
469 * offset.
470 */
471 int
472 vnet_sysctl_handle_int(SYSCTL_HANDLER_ARGS)
473 {
474
475 if (arg1 != NULL)
476 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1);
477 return (sysctl_handle_int(oidp, arg1, arg2, req));
478 }
479
480 int
481 vnet_sysctl_handle_opaque(SYSCTL_HANDLER_ARGS)
482 {
483
484 if (arg1 != NULL)
485 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1);
486 return (sysctl_handle_opaque(oidp, arg1, arg2, req));
487 }
488
489 int
490 vnet_sysctl_handle_string(SYSCTL_HANDLER_ARGS)
491 {
492
493 if (arg1 != NULL)
494 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1);
495 return (sysctl_handle_string(oidp, arg1, arg2, req));
496 }
497
498 int
499 vnet_sysctl_handle_uint(SYSCTL_HANDLER_ARGS)
500 {
501
502 if (arg1 != NULL)
503 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1);
504 return (sysctl_handle_int(oidp, arg1, arg2, req));
505 }
506
507 /*
508 * Support for special SYSINIT handlers registered via VNET_SYSINIT()
509 * and VNET_SYSUNINIT().
510 */
511 void
512 vnet_register_sysinit(void *arg)
513 {
514 struct vnet_sysinit *vs, *vs2;
515 struct vnet *vnet;
516
517 vs = arg;
518 KASSERT(vs->subsystem > SI_SUB_VNET, ("vnet sysinit too early"));
519
520 /* Add the constructor to the global list of vnet constructors. */
521 VNET_SYSINIT_WLOCK();
522 TAILQ_FOREACH(vs2, &vnet_constructors, link) {
523 if (vs2->subsystem > vs->subsystem)
524 break;
525 if (vs2->subsystem == vs->subsystem && vs2->order > vs->order)
526 break;
527 }
528 if (vs2 != NULL)
529 TAILQ_INSERT_BEFORE(vs2, vs, link);
530 else
531 TAILQ_INSERT_TAIL(&vnet_constructors, vs, link);
532
533 /*
534 * Invoke the constructor on all the existing vnets when it is
535 * registered.
536 */
537 VNET_FOREACH(vnet) {
538 CURVNET_SET_QUIET(vnet);
539 vs->func(vs->arg);
540 CURVNET_RESTORE();
541 }
542 VNET_SYSINIT_WUNLOCK();
543 }
544
545 void
546 vnet_deregister_sysinit(void *arg)
547 {
548 struct vnet_sysinit *vs;
549
550 vs = arg;
551
552 /* Remove the constructor from the global list of vnet constructors. */
553 VNET_SYSINIT_WLOCK();
554 TAILQ_REMOVE(&vnet_constructors, vs, link);
555 VNET_SYSINIT_WUNLOCK();
556 }
557
558 void
559 vnet_register_sysuninit(void *arg)
560 {
561 struct vnet_sysinit *vs, *vs2;
562
563 vs = arg;
564
565 /* Add the destructor to the global list of vnet destructors. */
566 VNET_SYSINIT_WLOCK();
567 TAILQ_FOREACH(vs2, &vnet_destructors, link) {
568 if (vs2->subsystem > vs->subsystem)
569 break;
570 if (vs2->subsystem == vs->subsystem && vs2->order > vs->order)
571 break;
572 }
573 if (vs2 != NULL)
574 TAILQ_INSERT_BEFORE(vs2, vs, link);
575 else
576 TAILQ_INSERT_TAIL(&vnet_destructors, vs, link);
577 VNET_SYSINIT_WUNLOCK();
578 }
579
580 void
581 vnet_deregister_sysuninit(void *arg)
582 {
583 struct vnet_sysinit *vs;
584 struct vnet *vnet;
585
586 vs = arg;
587
588 /*
589 * Invoke the destructor on all the existing vnets when it is
590 * deregistered.
591 */
592 VNET_SYSINIT_WLOCK();
593 VNET_FOREACH(vnet) {
594 CURVNET_SET_QUIET(vnet);
595 vs->func(vs->arg);
596 CURVNET_RESTORE();
597 }
598
599 /* Remove the destructor from the global list of vnet destructors. */
600 TAILQ_REMOVE(&vnet_destructors, vs, link);
601 VNET_SYSINIT_WUNLOCK();
602 }
603
604 /*
605 * Invoke all registered vnet constructors on the current vnet. Used during
606 * vnet construction. The caller is responsible for ensuring the new vnet is
607 * the current vnet and that the vnet_sysinit_sxlock lock is locked.
608 */
609 void
610 vnet_sysinit(void)
611 {
612 struct vnet_sysinit *vs;
613
614 VNET_SYSINIT_RLOCK();
615 TAILQ_FOREACH(vs, &vnet_constructors, link) {
616 vs->func(vs->arg);
617 }
618 VNET_SYSINIT_RUNLOCK();
619 }
620
621 /*
622 * Invoke all registered vnet destructors on the current vnet. Used during
623 * vnet destruction. The caller is responsible for ensuring the dying vnet
624 * the current vnet and that the vnet_sysinit_sxlock lock is locked.
625 */
626 void
627 vnet_sysuninit(void)
628 {
629 struct vnet_sysinit *vs;
630
631 VNET_SYSINIT_RLOCK();
632 TAILQ_FOREACH_REVERSE(vs, &vnet_destructors, vnet_sysuninit_head,
633 link) {
634 vs->func(vs->arg);
635 }
636 VNET_SYSINIT_RUNLOCK();
637 }
638
639 /*
640 * EVENTHANDLER(9) extensions.
641 */
642 /*
643 * Invoke the eventhandler function originally registered with the possibly
644 * registered argument for all virtual network stack instances.
645 *
646 * This iterator can only be used for eventhandlers that do not take any
647 * additional arguments, as we do ignore the variadic arguments from the
648 * EVENTHANDLER_INVOKE() call.
649 */
650 void
651 vnet_global_eventhandler_iterator_func(void *arg, ...)
652 {
653 VNET_ITERATOR_DECL(vnet_iter);
654 struct eventhandler_entry_vimage *v_ee;
655
656 /*
657 * There is a bug here in that we should actually cast things to
658 * (struct eventhandler_entry_ ## name *) but that's not easily
659 * possible in here so just re-using the variadic version we
660 * defined for the generic vimage case.
661 */
662 v_ee = arg;
663 VNET_LIST_RLOCK();
664 VNET_FOREACH(vnet_iter) {
665 CURVNET_SET(vnet_iter);
666 ((vimage_iterator_func_t)v_ee->func)(v_ee->ee_arg);
667 CURVNET_RESTORE();
668 }
669 VNET_LIST_RUNLOCK();
670 }
671
672 #ifdef VNET_DEBUG
673 struct vnet_recursion {
674 SLIST_ENTRY(vnet_recursion) vnr_le;
675 const char *prev_fn;
676 const char *where_fn;
677 int where_line;
678 struct vnet *old_vnet;
679 struct vnet *new_vnet;
680 };
681
682 static SLIST_HEAD(, vnet_recursion) vnet_recursions =
683 SLIST_HEAD_INITIALIZER(vnet_recursions);
684
685 static void
686 vnet_print_recursion(struct vnet_recursion *vnr, int brief)
687 {
688
689 if (!brief)
690 printf("CURVNET_SET() recursion in ");
691 printf("%s() line %d, prev in %s()", vnr->where_fn, vnr->where_line,
692 vnr->prev_fn);
693 if (brief)
694 printf(", ");
695 else
696 printf("\n ");
697 printf("%p -> %p\n", vnr->old_vnet, vnr->new_vnet);
698 }
699
700 void
701 vnet_log_recursion(struct vnet *old_vnet, const char *old_fn, int line)
702 {
703 struct vnet_recursion *vnr;
704
705 /* Skip already logged recursion events. */
706 SLIST_FOREACH(vnr, &vnet_recursions, vnr_le)
707 if (vnr->prev_fn == old_fn &&
708 vnr->where_fn == curthread->td_vnet_lpush &&
709 vnr->where_line == line &&
710 (vnr->old_vnet == vnr->new_vnet) == (curvnet == old_vnet))
711 return;
712
713 vnr = malloc(sizeof(*vnr), M_VNET, M_NOWAIT | M_ZERO);
714 if (vnr == NULL)
715 panic("%s: malloc failed", __func__);
716 vnr->prev_fn = old_fn;
717 vnr->where_fn = curthread->td_vnet_lpush;
718 vnr->where_line = line;
719 vnr->old_vnet = old_vnet;
720 vnr->new_vnet = curvnet;
721
722 SLIST_INSERT_HEAD(&vnet_recursions, vnr, vnr_le);
723
724 vnet_print_recursion(vnr, 0);
725 #ifdef KDB
726 kdb_backtrace();
727 #endif
728 }
729 #endif /* VNET_DEBUG */
730
731 /*
732 * DDB(4).
733 */
734 #ifdef DDB
735 DB_SHOW_COMMAND(vnets, db_show_vnets)
736 {
737 VNET_ITERATOR_DECL(vnet_iter);
738
739 VNET_FOREACH(vnet_iter) {
740 db_printf("vnet = %p\n", vnet_iter);
741 db_printf(" vnet_magic_n = 0x%x (%s, orig 0x%x)\n",
742 vnet_iter->vnet_magic_n,
743 (vnet_iter->vnet_magic_n == VNET_MAGIC_N) ?
744 "ok" : "mismatch", VNET_MAGIC_N);
745 db_printf(" vnet_ifcnt = %u\n", vnet_iter->vnet_ifcnt);
746 db_printf(" vnet_sockcnt = %u\n", vnet_iter->vnet_sockcnt);
747 db_printf(" vnet_data_mem = %p\n", vnet_iter->vnet_data_mem);
748 db_printf(" vnet_data_base = 0x%jx\n",
749 (uintmax_t)vnet_iter->vnet_data_base);
750 db_printf("\n");
751 if (db_pager_quit)
752 break;
753 }
754 }
755
756 static void
757 db_show_vnet_print_vs(struct vnet_sysinit *vs, int ddb)
758 {
759 const char *vsname, *funcname;
760 c_db_sym_t sym;
761 db_expr_t offset;
762
763 #define xprint(...) \
764 if (ddb) \
765 db_printf(__VA_ARGS__); \
766 else \
767 printf(__VA_ARGS__)
768
769 if (vs == NULL) {
770 xprint("%s: no vnet_sysinit * given\n", __func__);
771 return;
772 }
773
774 sym = db_search_symbol((vm_offset_t)vs, DB_STGY_ANY, &offset);
775 db_symbol_values(sym, &vsname, NULL);
776 sym = db_search_symbol((vm_offset_t)vs->func, DB_STGY_PROC, &offset);
777 db_symbol_values(sym, &funcname, NULL);
778 xprint("%s(%p)\n", (vsname != NULL) ? vsname : "", vs);
779 xprint(" 0x%08x 0x%08x\n", vs->subsystem, vs->order);
780 xprint(" %p(%s)(%p)\n",
781 vs->func, (funcname != NULL) ? funcname : "", vs->arg);
782 #undef xprint
783 }
784
785 DB_SHOW_COMMAND(vnet_sysinit, db_show_vnet_sysinit)
786 {
787 struct vnet_sysinit *vs;
788
789 db_printf("VNET_SYSINIT vs Name(Ptr)\n");
790 db_printf(" Subsystem Order\n");
791 db_printf(" Function(Name)(Arg)\n");
792 TAILQ_FOREACH(vs, &vnet_constructors, link) {
793 db_show_vnet_print_vs(vs, 1);
794 if (db_pager_quit)
795 break;
796 }
797 }
798
799 DB_SHOW_COMMAND(vnet_sysuninit, db_show_vnet_sysuninit)
800 {
801 struct vnet_sysinit *vs;
802
803 db_printf("VNET_SYSUNINIT vs Name(Ptr)\n");
804 db_printf(" Subsystem Order\n");
805 db_printf(" Function(Name)(Arg)\n");
806 TAILQ_FOREACH_REVERSE(vs, &vnet_destructors, vnet_sysuninit_head,
807 link) {
808 db_show_vnet_print_vs(vs, 1);
809 if (db_pager_quit)
810 break;
811 }
812 }
813
814 #ifdef VNET_DEBUG
815 DB_SHOW_COMMAND(vnetrcrs, db_show_vnetrcrs)
816 {
817 struct vnet_recursion *vnr;
818
819 SLIST_FOREACH(vnr, &vnet_recursions, vnr_le)
820 vnet_print_recursion(vnr, 1);
821 }
822 #endif
823 #endif /* DDB */
Cache object: 0c6d3f17fa91c0852290709d421460a7
|