FreeBSD/Linux Kernel Cross Reference
sys/net/vnet.c
1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2004-2009 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
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40
41 #include "opt_ddb.h"
42 #include "opt_kdb.h"
43
44 #include <sys/param.h>
45 #include <sys/kdb.h>
46 #include <sys/kernel.h>
47 #include <sys/jail.h>
48 #include <sys/sdt.h>
49 #include <sys/systm.h>
50 #include <sys/sysctl.h>
51 #include <sys/eventhandler.h>
52 #include <sys/lock.h>
53 #include <sys/malloc.h>
54 #include <sys/proc.h>
55 #include <sys/socket.h>
56 #include <sys/sx.h>
57 #include <sys/sysctl.h>
58
59 #include <machine/stdarg.h>
60
61 #ifdef DDB
62 #include <ddb/ddb.h>
63 #include <ddb/db_sym.h>
64 #endif
65
66 #include <net/if.h>
67 #include <net/if_var.h>
68 #include <net/vnet.h>
69
70 /*-
71 * This file implements core functions for virtual network stacks:
72 *
73 * - Virtual network stack management functions.
74 *
75 * - Virtual network stack memory allocator, which virtualizes global
76 * variables in the network stack
77 *
78 * - Virtualized SYSINIT's/SYSUNINIT's, which allow network stack subsystems
79 * to register startup/shutdown events to be run for each virtual network
80 * stack instance.
81 */
82
83 FEATURE(vimage, "VIMAGE kernel virtualization");
84
85 static MALLOC_DEFINE(M_VNET, "vnet", "network stack control block");
86
87 /*
88 * The virtual network stack list has two read-write locks, one sleepable and
89 * the other not, so that the list can be stablized and walked in a variety
90 * of network stack contexts. Both must be acquired exclusively to modify
91 * the list, but a read lock of either lock is sufficient to walk the list.
92 */
93 struct rwlock vnet_rwlock;
94 struct sx vnet_sxlock;
95
96 #define VNET_LIST_WLOCK() do { \
97 sx_xlock(&vnet_sxlock); \
98 rw_wlock(&vnet_rwlock); \
99 } while (0)
100
101 #define VNET_LIST_WUNLOCK() do { \
102 rw_wunlock(&vnet_rwlock); \
103 sx_xunlock(&vnet_sxlock); \
104 } while (0)
105
106 struct vnet_list_head vnet_head;
107 struct vnet *vnet0;
108
109 /*
110 * The virtual network stack allocator provides storage for virtualized
111 * global variables. These variables are defined/declared using the
112 * VNET_DEFINE()/VNET_DECLARE() macros, which place them in the 'set_vnet'
113 * linker set. The details of the implementation are somewhat subtle, but
114 * allow the majority of most network subsystems to maintain
115 * virtualization-agnostic.
116 *
117 * The virtual network stack allocator handles variables in the base kernel
118 * vs. modules in similar but different ways. In both cases, virtualized
119 * global variables are marked as such by being declared to be part of the
120 * vnet linker set. These "master" copies of global variables serve two
121 * functions:
122 *
123 * (1) They contain static initialization or "default" values for global
124 * variables which will be propagated to each virtual network stack
125 * instance when created. As with normal global variables, they default
126 * to zero-filled.
127 *
128 * (2) They act as unique global names by which the variable can be referred
129 * to, regardless of network stack instance. The single global symbol
130 * will be used to calculate the location of a per-virtual instance
131 * variable at run-time.
132 *
133 * Each virtual network stack instance has a complete copy of each
134 * virtualized global variable, stored in a malloc'd block of memory
135 * referred to by vnet->vnet_data_mem. Critical to the design is that each
136 * per-instance memory block is laid out identically to the master block so
137 * that the offset of each global variable is the same across all blocks. To
138 * optimize run-time access, a precalculated 'base' address,
139 * vnet->vnet_data_base, is stored in each vnet, and is the amount that can
140 * be added to the address of a 'master' instance of a variable to get to the
141 * per-vnet instance.
142 *
143 * Virtualized global variables are handled in a similar manner, but as each
144 * module has its own 'set_vnet' linker set, and we want to keep all
145 * virtualized globals togther, we reserve space in the kernel's linker set
146 * for potential module variables using a per-vnet character array,
147 * 'modspace'. The virtual network stack allocator maintains a free list to
148 * track what space in the array is free (all, initially) and as modules are
149 * linked, allocates portions of the space to specific globals. The kernel
150 * module linker queries the virtual network stack allocator and will
151 * bind references of the global to the location during linking. It also
152 * calls into the virtual network stack allocator, once the memory is
153 * initialized, in order to propagate the new static initializations to all
154 * existing virtual network stack instances so that the soon-to-be executing
155 * module will find every network stack instance with proper default values.
156 */
157
158 /*
159 * Number of bytes of data in the 'set_vnet' linker set, and hence the total
160 * size of all kernel virtualized global variables, and the malloc(9) type
161 * that will be used to allocate it.
162 */
163 #define VNET_BYTES (VNET_STOP - VNET_START)
164
165 static MALLOC_DEFINE(M_VNET_DATA, "vnet_data", "VNET data");
166
167 /*
168 * VNET_MODMIN is the minimum number of bytes we will reserve for the sum of
169 * global variables across all loaded modules. As this actually sizes an
170 * array declared as a virtualized global variable in the kernel itself, and
171 * we want the virtualized global variable space to be page-sized, we may
172 * have more space than that in practice.
173 */
174 #define VNET_MODMIN (8 * PAGE_SIZE)
175 #define VNET_SIZE roundup2(VNET_BYTES, PAGE_SIZE)
176
177 /*
178 * Space to store virtualized global variables from loadable kernel modules,
179 * and the free list to manage it.
180 */
181 VNET_DEFINE_STATIC(char, modspace[VNET_MODMIN] __aligned(__alignof(void *)));
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 static MALLOC_DEFINE(M_VNET_DATA_FREE, "vnet_data_free",
207 "VNET resource accounting");
208 static TAILQ_HEAD(, vnet_data_free) vnet_data_free_head =
209 TAILQ_HEAD_INITIALIZER(vnet_data_free_head);
210 static struct sx vnet_data_free_lock;
211
212 SDT_PROVIDER_DEFINE(vnet);
213 SDT_PROBE_DEFINE1(vnet, functions, vnet_alloc, entry, "int");
214 SDT_PROBE_DEFINE2(vnet, functions, vnet_alloc, alloc, "int",
215 "struct vnet *");
216 SDT_PROBE_DEFINE2(vnet, functions, vnet_alloc, return,
217 "int", "struct vnet *");
218 SDT_PROBE_DEFINE2(vnet, functions, vnet_destroy, entry,
219 "int", "struct vnet *");
220 SDT_PROBE_DEFINE1(vnet, functions, vnet_destroy, return,
221 "int");
222
223 #ifdef DDB
224 static void db_show_vnet_print_vs(struct vnet_sysinit *, int);
225 #endif
226
227 /*
228 * Allocate a virtual network stack.
229 */
230 struct vnet *
231 vnet_alloc(void)
232 {
233 struct vnet *vnet;
234
235 SDT_PROBE1(vnet, functions, vnet_alloc, entry, __LINE__);
236 vnet = malloc(sizeof(struct vnet), M_VNET, M_WAITOK | M_ZERO);
237 vnet->vnet_magic_n = VNET_MAGIC_N;
238 vnet->vnet_state = 0;
239 SDT_PROBE2(vnet, functions, vnet_alloc, alloc, __LINE__, vnet);
240
241 /*
242 * Allocate storage for virtualized global variables and copy in
243 * initial values form our 'master' copy.
244 */
245 vnet->vnet_data_mem = malloc(VNET_SIZE, M_VNET_DATA, M_WAITOK);
246 memcpy(vnet->vnet_data_mem, (void *)VNET_START, VNET_BYTES);
247
248 /*
249 * All use of vnet-specific data will immediately subtract VNET_START
250 * from the base memory pointer, so pre-calculate that now to avoid
251 * it on each use.
252 */
253 vnet->vnet_data_base = (uintptr_t)vnet->vnet_data_mem - VNET_START;
254
255 /* Initialize / attach vnet module instances. */
256 CURVNET_SET_QUIET(vnet);
257 vnet_sysinit();
258 CURVNET_RESTORE();
259
260 VNET_LIST_WLOCK();
261 LIST_INSERT_HEAD(&vnet_head, vnet, vnet_le);
262 VNET_LIST_WUNLOCK();
263
264 SDT_PROBE2(vnet, functions, vnet_alloc, return, __LINE__, vnet);
265 return (vnet);
266 }
267
268 /*
269 * Destroy a virtual network stack.
270 */
271 void
272 vnet_destroy(struct vnet *vnet)
273 {
274
275 SDT_PROBE2(vnet, functions, vnet_destroy, entry, __LINE__, vnet);
276 KASSERT(vnet->vnet_sockcnt == 0,
277 ("%s: vnet still has sockets", __func__));
278
279 VNET_LIST_WLOCK();
280 LIST_REMOVE(vnet, vnet_le);
281 VNET_LIST_WUNLOCK();
282
283 CURVNET_SET_QUIET(vnet);
284 sx_xlock(&ifnet_detach_sxlock);
285 vnet_sysuninit();
286 sx_xunlock(&ifnet_detach_sxlock);
287 CURVNET_RESTORE();
288
289 /*
290 * Release storage for the virtual network stack instance.
291 */
292 free(vnet->vnet_data_mem, M_VNET_DATA);
293 vnet->vnet_data_mem = NULL;
294 vnet->vnet_data_base = 0;
295 vnet->vnet_magic_n = 0xdeadbeef;
296 free(vnet, M_VNET);
297 SDT_PROBE1(vnet, functions, vnet_destroy, return, __LINE__);
298 }
299
300 /*
301 * Boot time initialization and allocation of virtual network stacks.
302 */
303 static void
304 vnet_init_prelink(void *arg __unused)
305 {
306
307 rw_init(&vnet_rwlock, "vnet_rwlock");
308 sx_init(&vnet_sxlock, "vnet_sxlock");
309 sx_init(&vnet_sysinit_sxlock, "vnet_sysinit_sxlock");
310 LIST_INIT(&vnet_head);
311 }
312 SYSINIT(vnet_init_prelink, SI_SUB_VNET_PRELINK, SI_ORDER_FIRST,
313 vnet_init_prelink, NULL);
314
315 static void
316 vnet0_init(void *arg __unused)
317 {
318
319 if (bootverbose)
320 printf("VIMAGE (virtualized network stack) enabled\n");
321
322 /*
323 * We MUST clear curvnet in vi_init_done() before going SMP,
324 * otherwise CURVNET_SET() macros would scream about unnecessary
325 * curvnet recursions.
326 */
327 curvnet = prison0.pr_vnet = vnet0 = vnet_alloc();
328 }
329 SYSINIT(vnet0_init, SI_SUB_VNET, SI_ORDER_FIRST, vnet0_init, NULL);
330
331 static void
332 vnet_init_done(void *unused __unused)
333 {
334
335 curvnet = NULL;
336 }
337 SYSINIT(vnet_init_done, SI_SUB_VNET_DONE, SI_ORDER_ANY, vnet_init_done,
338 NULL);
339
340 /*
341 * Once on boot, initialize the modspace freelist to entirely cover modspace.
342 */
343 static void
344 vnet_data_startup(void *dummy __unused)
345 {
346 struct vnet_data_free *df;
347
348 df = malloc(sizeof(*df), M_VNET_DATA_FREE, M_WAITOK | M_ZERO);
349 df->vnd_start = (uintptr_t)&VNET_NAME(modspace);
350 df->vnd_len = VNET_MODMIN;
351 TAILQ_INSERT_HEAD(&vnet_data_free_head, df, vnd_link);
352 sx_init(&vnet_data_free_lock, "vnet_data alloc lock");
353 }
354 SYSINIT(vnet_data, SI_SUB_KLD, SI_ORDER_FIRST, vnet_data_startup, NULL);
355
356 /* Dummy VNET_SYSINIT to make sure we always reach the final end state. */
357 static void
358 vnet_sysinit_done(void *unused __unused)
359 {
360
361 return;
362 }
363 VNET_SYSINIT(vnet_sysinit_done, SI_SUB_VNET_DONE, SI_ORDER_ANY,
364 vnet_sysinit_done, NULL);
365
366 /*
367 * When a module is loaded and requires storage for a virtualized global
368 * variable, allocate space from the modspace free list. This interface
369 * should be used only by the kernel linker.
370 */
371 void *
372 vnet_data_alloc(int size)
373 {
374 struct vnet_data_free *df;
375 void *s;
376
377 s = NULL;
378 size = roundup2(size, sizeof(void *));
379 sx_xlock(&vnet_data_free_lock);
380 TAILQ_FOREACH(df, &vnet_data_free_head, vnd_link) {
381 if (df->vnd_len < size)
382 continue;
383 if (df->vnd_len == size) {
384 s = (void *)df->vnd_start;
385 TAILQ_REMOVE(&vnet_data_free_head, df, vnd_link);
386 free(df, M_VNET_DATA_FREE);
387 break;
388 }
389 s = (void *)df->vnd_start;
390 df->vnd_len -= size;
391 df->vnd_start = df->vnd_start + size;
392 break;
393 }
394 sx_xunlock(&vnet_data_free_lock);
395
396 return (s);
397 }
398
399 /*
400 * Free space for a virtualized global variable on module unload.
401 */
402 void
403 vnet_data_free(void *start_arg, int size)
404 {
405 struct vnet_data_free *df;
406 struct vnet_data_free *dn;
407 uintptr_t start;
408 uintptr_t end;
409
410 size = roundup2(size, sizeof(void *));
411 start = (uintptr_t)start_arg;
412 end = start + size;
413 /*
414 * Free a region of space and merge it with as many neighbors as
415 * possible. Keeping the list sorted simplifies this operation.
416 */
417 sx_xlock(&vnet_data_free_lock);
418 TAILQ_FOREACH(df, &vnet_data_free_head, vnd_link) {
419 if (df->vnd_start > end)
420 break;
421 /*
422 * If we expand at the end of an entry we may have to merge
423 * it with the one following it as well.
424 */
425 if (df->vnd_start + df->vnd_len == start) {
426 df->vnd_len += size;
427 dn = TAILQ_NEXT(df, vnd_link);
428 if (df->vnd_start + df->vnd_len == dn->vnd_start) {
429 df->vnd_len += dn->vnd_len;
430 TAILQ_REMOVE(&vnet_data_free_head, dn,
431 vnd_link);
432 free(dn, M_VNET_DATA_FREE);
433 }
434 sx_xunlock(&vnet_data_free_lock);
435 return;
436 }
437 if (df->vnd_start == end) {
438 df->vnd_start = start;
439 df->vnd_len += size;
440 sx_xunlock(&vnet_data_free_lock);
441 return;
442 }
443 }
444 dn = malloc(sizeof(*df), M_VNET_DATA_FREE, M_WAITOK | M_ZERO);
445 dn->vnd_start = start;
446 dn->vnd_len = size;
447 if (df)
448 TAILQ_INSERT_BEFORE(df, dn, vnd_link);
449 else
450 TAILQ_INSERT_TAIL(&vnet_data_free_head, dn, vnd_link);
451 sx_xunlock(&vnet_data_free_lock);
452 }
453
454 /*
455 * When a new virtualized global variable has been allocated, propagate its
456 * initial value to each already-allocated virtual network stack instance.
457 */
458 void
459 vnet_data_copy(void *start, int size)
460 {
461 struct vnet *vnet;
462
463 VNET_LIST_RLOCK();
464 LIST_FOREACH(vnet, &vnet_head, vnet_le)
465 memcpy((void *)((uintptr_t)vnet->vnet_data_base +
466 (uintptr_t)start), start, size);
467 VNET_LIST_RUNLOCK();
468 }
469
470 /*
471 * Support for special SYSINIT handlers registered via VNET_SYSINIT()
472 * and VNET_SYSUNINIT().
473 */
474 void
475 vnet_register_sysinit(void *arg)
476 {
477 struct vnet_sysinit *vs, *vs2;
478 struct vnet *vnet;
479
480 vs = arg;
481 KASSERT(vs->subsystem > SI_SUB_VNET, ("vnet sysinit too early"));
482
483 /* Add the constructor to the global list of vnet constructors. */
484 VNET_SYSINIT_WLOCK();
485 TAILQ_FOREACH(vs2, &vnet_constructors, link) {
486 if (vs2->subsystem > vs->subsystem)
487 break;
488 if (vs2->subsystem == vs->subsystem && vs2->order > vs->order)
489 break;
490 }
491 if (vs2 != NULL)
492 TAILQ_INSERT_BEFORE(vs2, vs, link);
493 else
494 TAILQ_INSERT_TAIL(&vnet_constructors, vs, link);
495
496 /*
497 * Invoke the constructor on all the existing vnets when it is
498 * registered.
499 */
500 VNET_FOREACH(vnet) {
501 CURVNET_SET_QUIET(vnet);
502 vs->func(vs->arg);
503 CURVNET_RESTORE();
504 }
505 VNET_SYSINIT_WUNLOCK();
506 }
507
508 void
509 vnet_deregister_sysinit(void *arg)
510 {
511 struct vnet_sysinit *vs;
512
513 vs = arg;
514
515 /* Remove the constructor from the global list of vnet constructors. */
516 VNET_SYSINIT_WLOCK();
517 TAILQ_REMOVE(&vnet_constructors, vs, link);
518 VNET_SYSINIT_WUNLOCK();
519 }
520
521 void
522 vnet_register_sysuninit(void *arg)
523 {
524 struct vnet_sysinit *vs, *vs2;
525
526 vs = arg;
527
528 /* Add the destructor to the global list of vnet destructors. */
529 VNET_SYSINIT_WLOCK();
530 TAILQ_FOREACH(vs2, &vnet_destructors, link) {
531 if (vs2->subsystem > vs->subsystem)
532 break;
533 if (vs2->subsystem == vs->subsystem && vs2->order > vs->order)
534 break;
535 }
536 if (vs2 != NULL)
537 TAILQ_INSERT_BEFORE(vs2, vs, link);
538 else
539 TAILQ_INSERT_TAIL(&vnet_destructors, vs, link);
540 VNET_SYSINIT_WUNLOCK();
541 }
542
543 void
544 vnet_deregister_sysuninit(void *arg)
545 {
546 struct vnet_sysinit *vs;
547 struct vnet *vnet;
548
549 vs = arg;
550
551 /*
552 * Invoke the destructor on all the existing vnets when it is
553 * deregistered.
554 */
555 VNET_SYSINIT_WLOCK();
556 VNET_FOREACH(vnet) {
557 CURVNET_SET_QUIET(vnet);
558 vs->func(vs->arg);
559 CURVNET_RESTORE();
560 }
561
562 /* Remove the destructor from the global list of vnet destructors. */
563 TAILQ_REMOVE(&vnet_destructors, vs, link);
564 VNET_SYSINIT_WUNLOCK();
565 }
566
567 /*
568 * Invoke all registered vnet constructors on the current vnet. Used during
569 * vnet construction. The caller is responsible for ensuring the new vnet is
570 * the current vnet and that the vnet_sysinit_sxlock lock is locked.
571 */
572 void
573 vnet_sysinit(void)
574 {
575 struct vnet_sysinit *vs;
576
577 VNET_SYSINIT_RLOCK();
578 TAILQ_FOREACH(vs, &vnet_constructors, link) {
579 curvnet->vnet_state = vs->subsystem;
580 vs->func(vs->arg);
581 }
582 VNET_SYSINIT_RUNLOCK();
583 }
584
585 /*
586 * Invoke all registered vnet destructors on the current vnet. Used during
587 * vnet destruction. The caller is responsible for ensuring the dying vnet
588 * the current vnet and that the vnet_sysinit_sxlock lock is locked.
589 */
590 void
591 vnet_sysuninit(void)
592 {
593 struct vnet_sysinit *vs;
594
595 VNET_SYSINIT_RLOCK();
596 TAILQ_FOREACH_REVERSE(vs, &vnet_destructors, vnet_sysuninit_head,
597 link) {
598 curvnet->vnet_state = vs->subsystem;
599 vs->func(vs->arg);
600 }
601 VNET_SYSINIT_RUNLOCK();
602 }
603
604 /*
605 * EVENTHANDLER(9) extensions.
606 */
607 /*
608 * Invoke the eventhandler function originally registered with the possibly
609 * registered argument for all virtual network stack instances.
610 *
611 * This iterator can only be used for eventhandlers that do not take any
612 * additional arguments, as we do ignore the variadic arguments from the
613 * EVENTHANDLER_INVOKE() call.
614 */
615 void
616 vnet_global_eventhandler_iterator_func(void *arg, ...)
617 {
618 VNET_ITERATOR_DECL(vnet_iter);
619 struct eventhandler_entry_vimage *v_ee;
620
621 /*
622 * There is a bug here in that we should actually cast things to
623 * (struct eventhandler_entry_ ## name *) but that's not easily
624 * possible in here so just re-using the variadic version we
625 * defined for the generic vimage case.
626 */
627 v_ee = arg;
628 VNET_LIST_RLOCK();
629 VNET_FOREACH(vnet_iter) {
630 CURVNET_SET(vnet_iter);
631 ((vimage_iterator_func_t)v_ee->func)(v_ee->ee_arg);
632 CURVNET_RESTORE();
633 }
634 VNET_LIST_RUNLOCK();
635 }
636
637 #ifdef VNET_DEBUG
638 struct vnet_recursion {
639 SLIST_ENTRY(vnet_recursion) vnr_le;
640 const char *prev_fn;
641 const char *where_fn;
642 int where_line;
643 struct vnet *old_vnet;
644 struct vnet *new_vnet;
645 };
646
647 static SLIST_HEAD(, vnet_recursion) vnet_recursions =
648 SLIST_HEAD_INITIALIZER(vnet_recursions);
649
650 static void
651 vnet_print_recursion(struct vnet_recursion *vnr, int brief)
652 {
653
654 if (!brief)
655 printf("CURVNET_SET() recursion in ");
656 printf("%s() line %d, prev in %s()", vnr->where_fn, vnr->where_line,
657 vnr->prev_fn);
658 if (brief)
659 printf(", ");
660 else
661 printf("\n ");
662 printf("%p -> %p\n", vnr->old_vnet, vnr->new_vnet);
663 }
664
665 void
666 vnet_log_recursion(struct vnet *old_vnet, const char *old_fn, int line)
667 {
668 struct vnet_recursion *vnr;
669
670 /* Skip already logged recursion events. */
671 SLIST_FOREACH(vnr, &vnet_recursions, vnr_le)
672 if (vnr->prev_fn == old_fn &&
673 vnr->where_fn == curthread->td_vnet_lpush &&
674 vnr->where_line == line &&
675 (vnr->old_vnet == vnr->new_vnet) == (curvnet == old_vnet))
676 return;
677
678 vnr = malloc(sizeof(*vnr), M_VNET, M_NOWAIT | M_ZERO);
679 if (vnr == NULL)
680 panic("%s: malloc failed", __func__);
681 vnr->prev_fn = old_fn;
682 vnr->where_fn = curthread->td_vnet_lpush;
683 vnr->where_line = line;
684 vnr->old_vnet = old_vnet;
685 vnr->new_vnet = curvnet;
686
687 SLIST_INSERT_HEAD(&vnet_recursions, vnr, vnr_le);
688
689 vnet_print_recursion(vnr, 0);
690 #ifdef KDB
691 kdb_backtrace();
692 #endif
693 }
694 #endif /* VNET_DEBUG */
695
696 /*
697 * DDB(4).
698 */
699 #ifdef DDB
700 static void
701 db_vnet_print(struct vnet *vnet)
702 {
703
704 db_printf("vnet = %p\n", vnet);
705 db_printf(" vnet_magic_n = %#08x (%s, orig %#08x)\n",
706 vnet->vnet_magic_n,
707 (vnet->vnet_magic_n == VNET_MAGIC_N) ?
708 "ok" : "mismatch", VNET_MAGIC_N);
709 db_printf(" vnet_ifcnt = %u\n", vnet->vnet_ifcnt);
710 db_printf(" vnet_sockcnt = %u\n", vnet->vnet_sockcnt);
711 db_printf(" vnet_data_mem = %p\n", vnet->vnet_data_mem);
712 db_printf(" vnet_data_base = %#jx\n",
713 (uintmax_t)vnet->vnet_data_base);
714 db_printf(" vnet_state = %#08x\n", vnet->vnet_state);
715 db_printf("\n");
716 }
717
718 DB_SHOW_ALL_COMMAND(vnets, db_show_all_vnets)
719 {
720 VNET_ITERATOR_DECL(vnet_iter);
721
722 VNET_FOREACH(vnet_iter) {
723 db_vnet_print(vnet_iter);
724 if (db_pager_quit)
725 break;
726 }
727 }
728
729 DB_SHOW_COMMAND(vnet, db_show_vnet)
730 {
731
732 if (!have_addr) {
733 db_printf("usage: show vnet <struct vnet *>\n");
734 return;
735 }
736
737 db_vnet_print((struct vnet *)addr);
738 }
739
740 static void
741 db_show_vnet_print_vs(struct vnet_sysinit *vs, int ddb)
742 {
743 const char *vsname, *funcname;
744 c_db_sym_t sym;
745 db_expr_t offset;
746
747 #define xprint(...) \
748 if (ddb) \
749 db_printf(__VA_ARGS__); \
750 else \
751 printf(__VA_ARGS__)
752
753 if (vs == NULL) {
754 xprint("%s: no vnet_sysinit * given\n", __func__);
755 return;
756 }
757
758 sym = db_search_symbol((vm_offset_t)vs, DB_STGY_ANY, &offset);
759 db_symbol_values(sym, &vsname, NULL);
760 sym = db_search_symbol((vm_offset_t)vs->func, DB_STGY_PROC, &offset);
761 db_symbol_values(sym, &funcname, NULL);
762 xprint("%s(%p)\n", (vsname != NULL) ? vsname : "", vs);
763 xprint(" %#08x %#08x\n", vs->subsystem, vs->order);
764 xprint(" %p(%s)(%p)\n",
765 vs->func, (funcname != NULL) ? funcname : "", vs->arg);
766 #undef xprint
767 }
768
769 DB_SHOW_COMMAND(vnet_sysinit, db_show_vnet_sysinit)
770 {
771 struct vnet_sysinit *vs;
772
773 db_printf("VNET_SYSINIT vs Name(Ptr)\n");
774 db_printf(" Subsystem Order\n");
775 db_printf(" Function(Name)(Arg)\n");
776 TAILQ_FOREACH(vs, &vnet_constructors, link) {
777 db_show_vnet_print_vs(vs, 1);
778 if (db_pager_quit)
779 break;
780 }
781 }
782
783 DB_SHOW_COMMAND(vnet_sysuninit, db_show_vnet_sysuninit)
784 {
785 struct vnet_sysinit *vs;
786
787 db_printf("VNET_SYSUNINIT vs Name(Ptr)\n");
788 db_printf(" Subsystem Order\n");
789 db_printf(" Function(Name)(Arg)\n");
790 TAILQ_FOREACH_REVERSE(vs, &vnet_destructors, vnet_sysuninit_head,
791 link) {
792 db_show_vnet_print_vs(vs, 1);
793 if (db_pager_quit)
794 break;
795 }
796 }
797
798 #ifdef VNET_DEBUG
799 DB_SHOW_COMMAND(vnetrcrs, db_show_vnetrcrs)
800 {
801 struct vnet_recursion *vnr;
802
803 SLIST_FOREACH(vnr, &vnet_recursions, vnr_le)
804 vnet_print_recursion(vnr, 1);
805 }
806 #endif
807 #endif /* DDB */
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