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
42 #include <sys/param.h>
43 #include <sys/kdb.h>
44 #include <sys/kernel.h>
45 #include <sys/jail.h>
46 #include <sys/sdt.h>
47 #include <sys/systm.h>
48 #include <sys/sysctl.h>
49 #include <sys/eventhandler.h>
50 #include <sys/lock.h>
51 #include <sys/malloc.h>
52 #include <sys/proc.h>
53 #include <sys/socket.h>
54 #include <sys/sx.h>
55 #include <sys/sysctl.h>
56
57 #include <machine/stdarg.h>
58
59 #ifdef DDB
60 #include <ddb/ddb.h>
61 #include <ddb/db_sym.h>
62 #endif
63
64 #include <net/if.h>
65 #include <net/if_var.h>
66 #include <net/vnet.h>
67
68 /*-
69 * This file implements core functions for virtual network stacks:
70 *
71 * - Virtual network stack management functions.
72 *
73 * - Virtual network stack memory allocator, which virtualizes global
74 * variables in the network stack
75 *
76 * - Virtualized SYSINIT's/SYSUNINIT's, which allow network stack subsystems
77 * to register startup/shutdown events to be run for each virtual network
78 * stack instance.
79 */
80
81 FEATURE(vimage, "VIMAGE kernel virtualization");
82
83 static MALLOC_DEFINE(M_VNET, "vnet", "network stack control block");
84
85 /*
86 * The virtual network stack list has two read-write locks, one sleepable and
87 * the other not, so that the list can be stablized and walked in a variety
88 * of network stack contexts. Both must be acquired exclusively to modify
89 * the list, but a read lock of either lock is sufficient to walk the list.
90 */
91 struct rwlock vnet_rwlock;
92 struct sx vnet_sxlock;
93
94 #define VNET_LIST_WLOCK() do { \
95 sx_xlock(&vnet_sxlock); \
96 rw_wlock(&vnet_rwlock); \
97 } while (0)
98
99 #define VNET_LIST_WUNLOCK() do { \
100 rw_wunlock(&vnet_rwlock); \
101 sx_xunlock(&vnet_sxlock); \
102 } while (0)
103
104 struct vnet_list_head vnet_head;
105 struct vnet *vnet0;
106
107 /*
108 * The virtual network stack allocator provides storage for virtualized
109 * global variables. These variables are defined/declared using the
110 * VNET_DEFINE()/VNET_DECLARE() macros, which place them in the 'set_vnet'
111 * linker set. The details of the implementation are somewhat subtle, but
112 * allow the majority of most network subsystems to maintain
113 * virtualization-agnostic.
114 *
115 * The virtual network stack allocator handles variables in the base kernel
116 * vs. modules in similar but different ways. In both cases, virtualized
117 * global variables are marked as such by being declared to be part of the
118 * vnet linker set. These "master" copies of global variables serve two
119 * functions:
120 *
121 * (1) They contain static initialization or "default" values for global
122 * variables which will be propagated to each virtual network stack
123 * instance when created. As with normal global variables, they default
124 * to zero-filled.
125 *
126 * (2) They act as unique global names by which the variable can be referred
127 * to, regardless of network stack instance. The single global symbol
128 * will be used to calculate the location of a per-virtual instance
129 * variable at run-time.
130 *
131 * Each virtual network stack instance has a complete copy of each
132 * virtualized global variable, stored in a malloc'd block of memory
133 * referred to by vnet->vnet_data_mem. Critical to the design is that each
134 * per-instance memory block is laid out identically to the master block so
135 * that the offset of each global variable is the same across all blocks. To
136 * optimize run-time access, a precalculated 'base' address,
137 * vnet->vnet_data_base, is stored in each vnet, and is the amount that can
138 * be added to the address of a 'master' instance of a variable to get to the
139 * per-vnet instance.
140 *
141 * Virtualized global variables are handled in a similar manner, but as each
142 * module has its own 'set_vnet' linker set, and we want to keep all
143 * virtualized globals togther, we reserve space in the kernel's linker set
144 * for potential module variables using a per-vnet character array,
145 * 'modspace'. The virtual network stack allocator maintains a free list to
146 * track what space in the array is free (all, initially) and as modules are
147 * linked, allocates portions of the space to specific globals. The kernel
148 * module linker queries the virtual network stack allocator and will
149 * bind references of the global to the location during linking. It also
150 * calls into the virtual network stack allocator, once the memory is
151 * initialized, in order to propagate the new static initializations to all
152 * existing virtual network stack instances so that the soon-to-be executing
153 * module will find every network stack instance with proper default values.
154 */
155
156 /*
157 * Number of bytes of data in the 'set_vnet' linker set, and hence the total
158 * size of all kernel virtualized global variables, and the malloc(9) type
159 * that will be used to allocate it.
160 */
161 #define VNET_BYTES (VNET_STOP - VNET_START)
162
163 static MALLOC_DEFINE(M_VNET_DATA, "vnet_data", "VNET data");
164
165 /*
166 * VNET_MODMIN is the minimum number of bytes we will reserve for the sum of
167 * global variables across all loaded modules. As this actually sizes an
168 * array declared as a virtualized global variable in the kernel itself, and
169 * we want the virtualized global variable space to be page-sized, we may
170 * have more space than that in practice.
171 */
172 #define VNET_MODMIN 8192
173 #define VNET_SIZE roundup2(VNET_BYTES, PAGE_SIZE)
174 #define VNET_MODSIZE (VNET_SIZE - (VNET_BYTES - VNET_MODMIN))
175
176 /*
177 * Space to store virtualized global variables from loadable kernel modules,
178 * and the free list to manage it.
179 */
180 static VNET_DEFINE(char, modspace[VNET_MODMIN]);
181
182 /*
183 * Global lists of subsystem constructor and destructors for vnets. They are
184 * registered via VNET_SYSINIT() and VNET_SYSUNINIT(). Both lists are
185 * protected by the vnet_sysinit_sxlock global lock.
186 */
187 static TAILQ_HEAD(vnet_sysinit_head, vnet_sysinit) vnet_constructors =
188 TAILQ_HEAD_INITIALIZER(vnet_constructors);
189 static TAILQ_HEAD(vnet_sysuninit_head, vnet_sysinit) vnet_destructors =
190 TAILQ_HEAD_INITIALIZER(vnet_destructors);
191
192 struct sx vnet_sysinit_sxlock;
193
194 #define VNET_SYSINIT_WLOCK() sx_xlock(&vnet_sysinit_sxlock);
195 #define VNET_SYSINIT_WUNLOCK() sx_xunlock(&vnet_sysinit_sxlock);
196 #define VNET_SYSINIT_RLOCK() sx_slock(&vnet_sysinit_sxlock);
197 #define VNET_SYSINIT_RUNLOCK() sx_sunlock(&vnet_sysinit_sxlock);
198
199 struct vnet_data_free {
200 uintptr_t vnd_start;
201 int vnd_len;
202 TAILQ_ENTRY(vnet_data_free) vnd_link;
203 };
204
205 static MALLOC_DEFINE(M_VNET_DATA_FREE, "vnet_data_free",
206 "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, "int");
213 SDT_PROBE_DEFINE2(vnet, functions, vnet_alloc, alloc, "int",
214 "struct vnet *");
215 SDT_PROBE_DEFINE2(vnet, functions, vnet_alloc, return,
216 "int", "struct vnet *");
217 SDT_PROBE_DEFINE2(vnet, functions, vnet_destroy, entry,
218 "int", "struct vnet *");
219 SDT_PROBE_DEFINE1(vnet, functions, vnet_destroy, return,
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 *
vnet_alloc(void)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
vnet_destroy(struct vnet * vnet)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
vnet_init_prelink(void * arg)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
vnet0_init(void * arg)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
vnet_init_done(void * unused)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
vnet_data_startup(void * dummy __unused)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 *
vnet_data_alloc(int size)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
vnet_data_free(void * start_arg,int size)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
vnet_data_copy(void * start,int size)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 * Support for special SYSINIT handlers registered via VNET_SYSINIT()
468 * and VNET_SYSUNINIT().
469 */
470 void
vnet_register_sysinit(void * arg)471 vnet_register_sysinit(void *arg)
472 {
473 struct vnet_sysinit *vs, *vs2;
474 struct vnet *vnet;
475
476 vs = arg;
477 KASSERT(vs->subsystem > SI_SUB_VNET, ("vnet sysinit too early"));
478
479 /* Add the constructor to the global list of vnet constructors. */
480 VNET_SYSINIT_WLOCK();
481 TAILQ_FOREACH(vs2, &vnet_constructors, link) {
482 if (vs2->subsystem > vs->subsystem)
483 break;
484 if (vs2->subsystem == vs->subsystem && vs2->order > vs->order)
485 break;
486 }
487 if (vs2 != NULL)
488 TAILQ_INSERT_BEFORE(vs2, vs, link);
489 else
490 TAILQ_INSERT_TAIL(&vnet_constructors, vs, link);
491
492 /*
493 * Invoke the constructor on all the existing vnets when it is
494 * registered.
495 */
496 VNET_FOREACH(vnet) {
497 CURVNET_SET_QUIET(vnet);
498 vs->func(vs->arg);
499 CURVNET_RESTORE();
500 }
501 VNET_SYSINIT_WUNLOCK();
502 }
503
504 void
vnet_deregister_sysinit(void * arg)505 vnet_deregister_sysinit(void *arg)
506 {
507 struct vnet_sysinit *vs;
508
509 vs = arg;
510
511 /* Remove the constructor from the global list of vnet constructors. */
512 VNET_SYSINIT_WLOCK();
513 TAILQ_REMOVE(&vnet_constructors, vs, link);
514 VNET_SYSINIT_WUNLOCK();
515 }
516
517 void
vnet_register_sysuninit(void * arg)518 vnet_register_sysuninit(void *arg)
519 {
520 struct vnet_sysinit *vs, *vs2;
521
522 vs = arg;
523
524 /* Add the destructor to the global list of vnet destructors. */
525 VNET_SYSINIT_WLOCK();
526 TAILQ_FOREACH(vs2, &vnet_destructors, link) {
527 if (vs2->subsystem > vs->subsystem)
528 break;
529 if (vs2->subsystem == vs->subsystem && vs2->order > vs->order)
530 break;
531 }
532 if (vs2 != NULL)
533 TAILQ_INSERT_BEFORE(vs2, vs, link);
534 else
535 TAILQ_INSERT_TAIL(&vnet_destructors, vs, link);
536 VNET_SYSINIT_WUNLOCK();
537 }
538
539 void
vnet_deregister_sysuninit(void * arg)540 vnet_deregister_sysuninit(void *arg)
541 {
542 struct vnet_sysinit *vs;
543 struct vnet *vnet;
544
545 vs = arg;
546
547 /*
548 * Invoke the destructor on all the existing vnets when it is
549 * deregistered.
550 */
551 VNET_SYSINIT_WLOCK();
552 VNET_FOREACH(vnet) {
553 CURVNET_SET_QUIET(vnet);
554 vs->func(vs->arg);
555 CURVNET_RESTORE();
556 }
557
558 /* Remove the destructor from the global list of vnet destructors. */
559 TAILQ_REMOVE(&vnet_destructors, vs, link);
560 VNET_SYSINIT_WUNLOCK();
561 }
562
563 /*
564 * Invoke all registered vnet constructors on the current vnet. Used during
565 * vnet construction. The caller is responsible for ensuring the new vnet is
566 * the current vnet and that the vnet_sysinit_sxlock lock is locked.
567 */
568 void
vnet_sysinit(void)569 vnet_sysinit(void)
570 {
571 struct vnet_sysinit *vs;
572
573 VNET_SYSINIT_RLOCK();
574 TAILQ_FOREACH(vs, &vnet_constructors, link) {
575 vs->func(vs->arg);
576 }
577 VNET_SYSINIT_RUNLOCK();
578 }
579
580 /*
581 * Invoke all registered vnet destructors on the current vnet. Used during
582 * vnet destruction. The caller is responsible for ensuring the dying vnet
583 * the current vnet and that the vnet_sysinit_sxlock lock is locked.
584 */
585 void
vnet_sysuninit(void)586 vnet_sysuninit(void)
587 {
588 struct vnet_sysinit *vs;
589
590 VNET_SYSINIT_RLOCK();
591 TAILQ_FOREACH_REVERSE(vs, &vnet_destructors, vnet_sysuninit_head,
592 link) {
593 vs->func(vs->arg);
594 }
595 VNET_SYSINIT_RUNLOCK();
596 }
597
598 /*
599 * EVENTHANDLER(9) extensions.
600 */
601 /*
602 * Invoke the eventhandler function originally registered with the possibly
603 * registered argument for all virtual network stack instances.
604 *
605 * This iterator can only be used for eventhandlers that do not take any
606 * additional arguments, as we do ignore the variadic arguments from the
607 * EVENTHANDLER_INVOKE() call.
608 */
609 void
vnet_global_eventhandler_iterator_func(void * arg,...)610 vnet_global_eventhandler_iterator_func(void *arg, ...)
611 {
612 VNET_ITERATOR_DECL(vnet_iter);
613 struct eventhandler_entry_vimage *v_ee;
614
615 /*
616 * There is a bug here in that we should actually cast things to
617 * (struct eventhandler_entry_ ## name *) but that's not easily
618 * possible in here so just re-using the variadic version we
619 * defined for the generic vimage case.
620 */
621 v_ee = arg;
622 VNET_LIST_RLOCK();
623 VNET_FOREACH(vnet_iter) {
624 CURVNET_SET(vnet_iter);
625 ((vimage_iterator_func_t)v_ee->func)(v_ee->ee_arg);
626 CURVNET_RESTORE();
627 }
628 VNET_LIST_RUNLOCK();
629 }
630
631 #ifdef VNET_DEBUG
632 struct vnet_recursion {
633 SLIST_ENTRY(vnet_recursion) vnr_le;
634 const char *prev_fn;
635 const char *where_fn;
636 int where_line;
637 struct vnet *old_vnet;
638 struct vnet *new_vnet;
639 };
640
641 static SLIST_HEAD(, vnet_recursion) vnet_recursions =
642 SLIST_HEAD_INITIALIZER(vnet_recursions);
643
644 static void
vnet_print_recursion(struct vnet_recursion * vnr,int brief)645 vnet_print_recursion(struct vnet_recursion *vnr, int brief)
646 {
647
648 if (!brief)
649 printf("CURVNET_SET() recursion in ");
650 printf("%s() line %d, prev in %s()", vnr->where_fn, vnr->where_line,
651 vnr->prev_fn);
652 if (brief)
653 printf(", ");
654 else
655 printf("\n ");
656 printf("%p -> %p\n", vnr->old_vnet, vnr->new_vnet);
657 }
658
659 void
vnet_log_recursion(struct vnet * old_vnet,const char * old_fn,int line)660 vnet_log_recursion(struct vnet *old_vnet, const char *old_fn, int line)
661 {
662 struct vnet_recursion *vnr;
663
664 /* Skip already logged recursion events. */
665 SLIST_FOREACH(vnr, &vnet_recursions, vnr_le)
666 if (vnr->prev_fn == old_fn &&
667 vnr->where_fn == curthread->td_vnet_lpush &&
668 vnr->where_line == line &&
669 (vnr->old_vnet == vnr->new_vnet) == (curvnet == old_vnet))
670 return;
671
672 vnr = malloc(sizeof(*vnr), M_VNET, M_NOWAIT | M_ZERO);
673 if (vnr == NULL)
674 panic("%s: malloc failed", __func__);
675 vnr->prev_fn = old_fn;
676 vnr->where_fn = curthread->td_vnet_lpush;
677 vnr->where_line = line;
678 vnr->old_vnet = old_vnet;
679 vnr->new_vnet = curvnet;
680
681 SLIST_INSERT_HEAD(&vnet_recursions, vnr, vnr_le);
682
683 vnet_print_recursion(vnr, 0);
684 #ifdef KDB
685 kdb_backtrace();
686 #endif
687 }
688 #endif /* VNET_DEBUG */
689
690 /*
691 * DDB(4).
692 */
693 #ifdef DDB
DB_SHOW_COMMAND(vnets,db_show_vnets)694 DB_SHOW_COMMAND(vnets, db_show_vnets)
695 {
696 VNET_ITERATOR_DECL(vnet_iter);
697
698 VNET_FOREACH(vnet_iter) {
699 db_printf("vnet = %p\n", vnet_iter);
700 db_printf(" vnet_magic_n = 0x%x (%s, orig 0x%x)\n",
701 vnet_iter->vnet_magic_n,
702 (vnet_iter->vnet_magic_n == VNET_MAGIC_N) ?
703 "ok" : "mismatch", VNET_MAGIC_N);
704 db_printf(" vnet_ifcnt = %u\n", vnet_iter->vnet_ifcnt);
705 db_printf(" vnet_sockcnt = %u\n", vnet_iter->vnet_sockcnt);
706 db_printf(" vnet_data_mem = %p\n", vnet_iter->vnet_data_mem);
707 db_printf(" vnet_data_base = 0x%jx\n",
708 (uintmax_t)vnet_iter->vnet_data_base);
709 db_printf("\n");
710 if (db_pager_quit)
711 break;
712 }
713 }
714
715 static void
db_show_vnet_print_vs(struct vnet_sysinit * vs,int ddb)716 db_show_vnet_print_vs(struct vnet_sysinit *vs, int ddb)
717 {
718 const char *vsname, *funcname;
719 c_db_sym_t sym;
720 db_expr_t offset;
721
722 #define xprint(...) \
723 if (ddb) \
724 db_printf(__VA_ARGS__); \
725 else \
726 printf(__VA_ARGS__)
727
728 if (vs == NULL) {
729 xprint("%s: no vnet_sysinit * given\n", __func__);
730 return;
731 }
732
733 sym = db_search_symbol((vm_offset_t)vs, DB_STGY_ANY, &offset);
734 db_symbol_values(sym, &vsname, NULL);
735 sym = db_search_symbol((vm_offset_t)vs->func, DB_STGY_PROC, &offset);
736 db_symbol_values(sym, &funcname, NULL);
737 xprint("%s(%p)\n", (vsname != NULL) ? vsname : "", vs);
738 xprint(" 0x%08x 0x%08x\n", vs->subsystem, vs->order);
739 xprint(" %p(%s)(%p)\n",
740 vs->func, (funcname != NULL) ? funcname : "", vs->arg);
741 #undef xprint
742 }
743
DB_SHOW_COMMAND(vnet_sysinit,db_show_vnet_sysinit)744 DB_SHOW_COMMAND(vnet_sysinit, db_show_vnet_sysinit)
745 {
746 struct vnet_sysinit *vs;
747
748 db_printf("VNET_SYSINIT vs Name(Ptr)\n");
749 db_printf(" Subsystem Order\n");
750 db_printf(" Function(Name)(Arg)\n");
751 TAILQ_FOREACH(vs, &vnet_constructors, link) {
752 db_show_vnet_print_vs(vs, 1);
753 if (db_pager_quit)
754 break;
755 }
756 }
757
DB_SHOW_COMMAND(vnet_sysuninit,db_show_vnet_sysuninit)758 DB_SHOW_COMMAND(vnet_sysuninit, db_show_vnet_sysuninit)
759 {
760 struct vnet_sysinit *vs;
761
762 db_printf("VNET_SYSUNINIT vs Name(Ptr)\n");
763 db_printf(" Subsystem Order\n");
764 db_printf(" Function(Name)(Arg)\n");
765 TAILQ_FOREACH_REVERSE(vs, &vnet_destructors, vnet_sysuninit_head,
766 link) {
767 db_show_vnet_print_vs(vs, 1);
768 if (db_pager_quit)
769 break;
770 }
771 }
772
773 #ifdef VNET_DEBUG
DB_SHOW_COMMAND(vnetrcrs,db_show_vnetrcrs)774 DB_SHOW_COMMAND(vnetrcrs, db_show_vnetrcrs)
775 {
776 struct vnet_recursion *vnr;
777
778 SLIST_FOREACH(vnr, &vnet_recursions, vnr_le)
779 vnet_print_recursion(vnr, 1);
780 }
781 #endif
782 #endif /* DDB */
783