FreeBSD/Linux Kernel Cross Reference
sys/geom/geom_subr.c
1 /*-
2 * Copyright (c) 2002 Poul-Henning Kamp
3 * Copyright (c) 2002 Networks Associates Technology, Inc.
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7 * and NAI Labs, the Security Research Division of Network Associates, Inc.
8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9 * DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. The names of the authors may not be used to endorse or promote
20 * products derived from this software without specific prior written
21 * permission.
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: releng/8.0/sys/geom/geom_subr.c 195257 2009-07-01 20:16:29Z trasz $");
38
39 #include "opt_ddb.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/devicestat.h>
44 #include <sys/kernel.h>
45 #include <sys/malloc.h>
46 #include <sys/bio.h>
47 #include <sys/sysctl.h>
48 #include <sys/proc.h>
49 #include <sys/kthread.h>
50 #include <sys/lock.h>
51 #include <sys/mutex.h>
52 #include <sys/errno.h>
53 #include <sys/sbuf.h>
54 #include <geom/geom.h>
55 #include <geom/geom_int.h>
56 #include <machine/stdarg.h>
57
58 #ifdef DDB
59 #include <ddb/ddb.h>
60 #endif
61
62 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
63 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
64 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;
65
66 struct g_hh00 {
67 struct g_class *mp;
68 int error;
69 int post;
70 };
71
72 /*
73 * This event offers a new class a chance to taste all preexisting providers.
74 */
75 static void
76 g_load_class(void *arg, int flag)
77 {
78 struct g_hh00 *hh;
79 struct g_class *mp2, *mp;
80 struct g_geom *gp;
81 struct g_provider *pp;
82
83 g_topology_assert();
84 if (flag == EV_CANCEL) /* XXX: can't happen ? */
85 return;
86 if (g_shutdown)
87 return;
88
89 hh = arg;
90 mp = hh->mp;
91 hh->error = 0;
92 if (hh->post) {
93 g_free(hh);
94 hh = NULL;
95 }
96 g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name);
97 KASSERT(mp->name != NULL && *mp->name != '\0',
98 ("GEOM class has no name"));
99 LIST_FOREACH(mp2, &g_classes, class) {
100 if (mp2 == mp) {
101 printf("The GEOM class %s is already loaded.\n",
102 mp2->name);
103 if (hh != NULL)
104 hh->error = EEXIST;
105 return;
106 } else if (strcmp(mp2->name, mp->name) == 0) {
107 printf("A GEOM class %s is already loaded.\n",
108 mp2->name);
109 if (hh != NULL)
110 hh->error = EEXIST;
111 return;
112 }
113 }
114
115 LIST_INIT(&mp->geom);
116 LIST_INSERT_HEAD(&g_classes, mp, class);
117 if (mp->init != NULL)
118 mp->init(mp);
119 if (mp->taste == NULL)
120 return;
121 LIST_FOREACH(mp2, &g_classes, class) {
122 if (mp == mp2)
123 continue;
124 LIST_FOREACH(gp, &mp2->geom, geom) {
125 LIST_FOREACH(pp, &gp->provider, provider) {
126 mp->taste(mp, pp, 0);
127 g_topology_assert();
128 }
129 }
130 }
131 }
132
133 static void
134 g_unload_class(void *arg, int flag)
135 {
136 struct g_hh00 *hh;
137 struct g_class *mp;
138 struct g_geom *gp;
139 struct g_provider *pp;
140 struct g_consumer *cp;
141 int error;
142
143 g_topology_assert();
144 hh = arg;
145 mp = hh->mp;
146 G_VALID_CLASS(mp);
147 g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name);
148
149 /*
150 * We allow unloading if we have no geoms, or a class
151 * method we can use to get rid of them.
152 */
153 if (!LIST_EMPTY(&mp->geom) && mp->destroy_geom == NULL) {
154 hh->error = EOPNOTSUPP;
155 return;
156 }
157
158 /* We refuse to unload if anything is open */
159 LIST_FOREACH(gp, &mp->geom, geom) {
160 LIST_FOREACH(pp, &gp->provider, provider)
161 if (pp->acr || pp->acw || pp->ace) {
162 hh->error = EBUSY;
163 return;
164 }
165 LIST_FOREACH(cp, &gp->consumer, consumer)
166 if (cp->acr || cp->acw || cp->ace) {
167 hh->error = EBUSY;
168 return;
169 }
170 }
171
172 /* Bar new entries */
173 mp->taste = NULL;
174 mp->config = NULL;
175
176 error = 0;
177 for (;;) {
178 gp = LIST_FIRST(&mp->geom);
179 if (gp == NULL)
180 break;
181 error = mp->destroy_geom(NULL, mp, gp);
182 if (error != 0)
183 break;
184 }
185 if (error == 0) {
186 if (mp->fini != NULL)
187 mp->fini(mp);
188 LIST_REMOVE(mp, class);
189 }
190 hh->error = error;
191 return;
192 }
193
194 int
195 g_modevent(module_t mod, int type, void *data)
196 {
197 struct g_hh00 *hh;
198 int error;
199 static int g_ignition;
200 struct g_class *mp;
201
202 mp = data;
203 if (mp->version != G_VERSION) {
204 printf("GEOM class %s has Wrong version %x\n",
205 mp->name, mp->version);
206 return (EINVAL);
207 }
208 if (!g_ignition) {
209 g_ignition++;
210 g_init();
211 }
212 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
213 hh->mp = data;
214 error = EOPNOTSUPP;
215 switch (type) {
216 case MOD_LOAD:
217 g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", hh->mp->name);
218 /*
219 * Once the system is not cold, MOD_LOAD calls will be
220 * from the userland and the g_event thread will be able
221 * to acknowledge their completion.
222 */
223 if (cold) {
224 hh->post = 1;
225 error = g_post_event(g_load_class, hh, M_WAITOK, NULL);
226 } else {
227 error = g_waitfor_event(g_load_class, hh, M_WAITOK,
228 NULL);
229 if (error == 0)
230 error = hh->error;
231 g_free(hh);
232 }
233 break;
234 case MOD_UNLOAD:
235 g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", hh->mp->name);
236 error = g_waitfor_event(g_unload_class, hh, M_WAITOK, NULL);
237 if (error == 0)
238 error = hh->error;
239 if (error == 0) {
240 KASSERT(LIST_EMPTY(&hh->mp->geom),
241 ("Unloaded class (%s) still has geom", hh->mp->name));
242 }
243 g_free(hh);
244 break;
245 default:
246 g_free(hh);
247 break;
248 }
249 return (error);
250 }
251
252 static void
253 g_retaste_event(void *arg, int flag)
254 {
255 struct g_class *cp, *mp;
256 struct g_geom *gp, *gp2;
257 struct g_hh00 *hh;
258 struct g_provider *pp;
259
260 g_topology_assert();
261 if (flag == EV_CANCEL) /* XXX: can't happen ? */
262 return;
263 if (g_shutdown)
264 return;
265
266 hh = arg;
267 mp = hh->mp;
268 hh->error = 0;
269 if (hh->post) {
270 g_free(hh);
271 hh = NULL;
272 }
273 g_trace(G_T_TOPOLOGY, "g_retaste(%s)", mp->name);
274
275 LIST_FOREACH(cp, &g_classes, class) {
276 LIST_FOREACH(gp, &cp->geom, geom) {
277 LIST_FOREACH(pp, &gp->provider, provider) {
278 if (pp->acr || pp->acw || pp->ace)
279 continue;
280 LIST_FOREACH(gp2, &mp->geom, geom) {
281 if (!strcmp(pp->name, gp2->name))
282 break;
283 }
284 if (gp2 != NULL)
285 g_wither_geom(gp2, ENXIO);
286 mp->taste(mp, pp, 0);
287 g_topology_assert();
288 }
289 }
290 }
291 }
292
293 int
294 g_retaste(struct g_class *mp)
295 {
296 struct g_hh00 *hh;
297 int error;
298
299 if (mp->taste == NULL)
300 return (EINVAL);
301
302 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
303 hh->mp = mp;
304
305 if (cold) {
306 hh->post = 1;
307 error = g_post_event(g_retaste_event, hh, M_WAITOK, NULL);
308 } else {
309 error = g_waitfor_event(g_retaste_event, hh, M_WAITOK, NULL);
310 if (error == 0)
311 error = hh->error;
312 g_free(hh);
313 }
314
315 return (error);
316 }
317
318 struct g_geom *
319 g_new_geomf(struct g_class *mp, const char *fmt, ...)
320 {
321 struct g_geom *gp;
322 va_list ap;
323 struct sbuf *sb;
324
325 g_topology_assert();
326 G_VALID_CLASS(mp);
327 sb = sbuf_new_auto();
328 va_start(ap, fmt);
329 sbuf_vprintf(sb, fmt, ap);
330 va_end(ap);
331 sbuf_finish(sb);
332 gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
333 gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
334 gp->class = mp;
335 gp->rank = 1;
336 LIST_INIT(&gp->consumer);
337 LIST_INIT(&gp->provider);
338 LIST_INSERT_HEAD(&mp->geom, gp, geom);
339 TAILQ_INSERT_HEAD(&geoms, gp, geoms);
340 strcpy(gp->name, sbuf_data(sb));
341 sbuf_delete(sb);
342 /* Fill in defaults from class */
343 gp->start = mp->start;
344 gp->spoiled = mp->spoiled;
345 gp->dumpconf = mp->dumpconf;
346 gp->access = mp->access;
347 gp->orphan = mp->orphan;
348 gp->ioctl = mp->ioctl;
349 return (gp);
350 }
351
352 void
353 g_destroy_geom(struct g_geom *gp)
354 {
355
356 g_topology_assert();
357 G_VALID_GEOM(gp);
358 g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
359 KASSERT(LIST_EMPTY(&gp->consumer),
360 ("g_destroy_geom(%s) with consumer(s) [%p]",
361 gp->name, LIST_FIRST(&gp->consumer)));
362 KASSERT(LIST_EMPTY(&gp->provider),
363 ("g_destroy_geom(%s) with provider(s) [%p]",
364 gp->name, LIST_FIRST(&gp->provider)));
365 g_cancel_event(gp);
366 LIST_REMOVE(gp, geom);
367 TAILQ_REMOVE(&geoms, gp, geoms);
368 g_free(gp->name);
369 g_free(gp);
370 }
371
372 /*
373 * This function is called (repeatedly) until the geom has withered away.
374 */
375 void
376 g_wither_geom(struct g_geom *gp, int error)
377 {
378 struct g_provider *pp;
379
380 g_topology_assert();
381 G_VALID_GEOM(gp);
382 g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name);
383 if (!(gp->flags & G_GEOM_WITHER)) {
384 gp->flags |= G_GEOM_WITHER;
385 LIST_FOREACH(pp, &gp->provider, provider)
386 if (!(pp->flags & G_PF_ORPHAN))
387 g_orphan_provider(pp, error);
388 }
389 g_do_wither();
390 }
391
392 /*
393 * Convenience function to destroy a particular provider.
394 */
395 void
396 g_wither_provider(struct g_provider *pp, int error)
397 {
398
399 pp->flags |= G_PF_WITHER;
400 if (!(pp->flags & G_PF_ORPHAN))
401 g_orphan_provider(pp, error);
402 }
403
404 /*
405 * This function is called (repeatedly) until the has withered away.
406 */
407 void
408 g_wither_geom_close(struct g_geom *gp, int error)
409 {
410 struct g_consumer *cp;
411
412 g_topology_assert();
413 G_VALID_GEOM(gp);
414 g_trace(G_T_TOPOLOGY, "g_wither_geom_close(%p(%s))", gp, gp->name);
415 LIST_FOREACH(cp, &gp->consumer, consumer)
416 if (cp->acr || cp->acw || cp->ace)
417 g_access(cp, -cp->acr, -cp->acw, -cp->ace);
418 g_wither_geom(gp, error);
419 }
420
421 /*
422 * This function is called (repeatedly) until we cant wash away more
423 * withered bits at present. Return value contains two bits. Bit 0
424 * set means "withering stuff we can't wash now", bit 1 means "call
425 * me again, there may be stuff I didn't get the first time around.
426 */
427 int
428 g_wither_washer()
429 {
430 struct g_class *mp;
431 struct g_geom *gp, *gp2;
432 struct g_provider *pp, *pp2;
433 struct g_consumer *cp, *cp2;
434 int result;
435
436 result = 0;
437 g_topology_assert();
438 LIST_FOREACH(mp, &g_classes, class) {
439 LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
440 LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
441 if (!(pp->flags & G_PF_WITHER))
442 continue;
443 if (LIST_EMPTY(&pp->consumers))
444 g_destroy_provider(pp);
445 else
446 result |= 1;
447 }
448 if (!(gp->flags & G_GEOM_WITHER))
449 continue;
450 LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
451 if (LIST_EMPTY(&pp->consumers))
452 g_destroy_provider(pp);
453 else
454 result |= 1;
455 }
456 LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp2) {
457 if (cp->acr || cp->acw || cp->ace) {
458 result |= 1;
459 continue;
460 }
461 if (cp->provider != NULL)
462 g_detach(cp);
463 g_destroy_consumer(cp);
464 result |= 2;
465 }
466 if (LIST_EMPTY(&gp->provider) &&
467 LIST_EMPTY(&gp->consumer))
468 g_destroy_geom(gp);
469 else
470 result |= 1;
471 }
472 }
473 return (result);
474 }
475
476 struct g_consumer *
477 g_new_consumer(struct g_geom *gp)
478 {
479 struct g_consumer *cp;
480
481 g_topology_assert();
482 G_VALID_GEOM(gp);
483 KASSERT(!(gp->flags & G_GEOM_WITHER),
484 ("g_new_consumer on WITHERing geom(%s) (class %s)",
485 gp->name, gp->class->name));
486 KASSERT(gp->orphan != NULL,
487 ("g_new_consumer on geom(%s) (class %s) without orphan",
488 gp->name, gp->class->name));
489
490 cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
491 cp->geom = gp;
492 cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED,
493 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
494 LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
495 return(cp);
496 }
497
498 void
499 g_destroy_consumer(struct g_consumer *cp)
500 {
501 struct g_geom *gp;
502
503 g_topology_assert();
504 G_VALID_CONSUMER(cp);
505 g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
506 KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
507 KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
508 KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
509 KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
510 g_cancel_event(cp);
511 gp = cp->geom;
512 LIST_REMOVE(cp, consumer);
513 devstat_remove_entry(cp->stat);
514 g_free(cp);
515 if (gp->flags & G_GEOM_WITHER)
516 g_do_wither();
517 }
518
519 static void
520 g_new_provider_event(void *arg, int flag)
521 {
522 struct g_class *mp;
523 struct g_provider *pp;
524 struct g_consumer *cp;
525
526 g_topology_assert();
527 if (flag == EV_CANCEL)
528 return;
529 if (g_shutdown)
530 return;
531 pp = arg;
532 G_VALID_PROVIDER(pp);
533 KASSERT(!(pp->flags & G_PF_WITHER),
534 ("g_new_provider_event but withered"));
535 LIST_FOREACH(mp, &g_classes, class) {
536 if (mp->taste == NULL)
537 continue;
538 LIST_FOREACH(cp, &pp->consumers, consumers)
539 if (cp->geom->class == mp)
540 break;
541 if (cp != NULL)
542 continue;
543 mp->taste(mp, pp, 0);
544 g_topology_assert();
545 }
546 }
547
548
549 struct g_provider *
550 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
551 {
552 struct g_provider *pp;
553 struct sbuf *sb;
554 va_list ap;
555
556 g_topology_assert();
557 G_VALID_GEOM(gp);
558 KASSERT(gp->access != NULL,
559 ("new provider on geom(%s) without ->access (class %s)",
560 gp->name, gp->class->name));
561 KASSERT(gp->start != NULL,
562 ("new provider on geom(%s) without ->start (class %s)",
563 gp->name, gp->class->name));
564 KASSERT(!(gp->flags & G_GEOM_WITHER),
565 ("new provider on WITHERing geom(%s) (class %s)",
566 gp->name, gp->class->name));
567 sb = sbuf_new_auto();
568 va_start(ap, fmt);
569 sbuf_vprintf(sb, fmt, ap);
570 va_end(ap);
571 sbuf_finish(sb);
572 pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
573 pp->name = (char *)(pp + 1);
574 strcpy(pp->name, sbuf_data(sb));
575 sbuf_delete(sb);
576 LIST_INIT(&pp->consumers);
577 pp->error = ENXIO;
578 pp->geom = gp;
579 pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED,
580 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
581 LIST_INSERT_HEAD(&gp->provider, pp, provider);
582 g_post_event(g_new_provider_event, pp, M_WAITOK, pp, gp, NULL);
583 return (pp);
584 }
585
586 void
587 g_error_provider(struct g_provider *pp, int error)
588 {
589
590 /* G_VALID_PROVIDER(pp); We may not have g_topology */
591 pp->error = error;
592 }
593
594 struct g_provider *
595 g_provider_by_name(char const *arg)
596 {
597 struct g_class *cp;
598 struct g_geom *gp;
599 struct g_provider *pp;
600
601 LIST_FOREACH(cp, &g_classes, class) {
602 LIST_FOREACH(gp, &cp->geom, geom) {
603 LIST_FOREACH(pp, &gp->provider, provider) {
604 if (!strcmp(arg, pp->name))
605 return (pp);
606 }
607 }
608 }
609 return (NULL);
610 }
611
612 void
613 g_destroy_provider(struct g_provider *pp)
614 {
615 struct g_geom *gp;
616
617 g_topology_assert();
618 G_VALID_PROVIDER(pp);
619 KASSERT(LIST_EMPTY(&pp->consumers),
620 ("g_destroy_provider but attached"));
621 KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
622 KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
623 KASSERT (pp->ace == 0, ("g_destroy_provider with ace"));
624 g_cancel_event(pp);
625 LIST_REMOVE(pp, provider);
626 gp = pp->geom;
627 devstat_remove_entry(pp->stat);
628 g_free(pp);
629 if ((gp->flags & G_GEOM_WITHER))
630 g_do_wither();
631 }
632
633 /*
634 * We keep the "geoms" list sorted by topological order (== increasing
635 * numerical rank) at all times.
636 * When an attach is done, the attaching geoms rank is invalidated
637 * and it is moved to the tail of the list.
638 * All geoms later in the sequence has their ranks reevaluated in
639 * sequence. If we cannot assign rank to a geom because it's
640 * prerequisites do not have rank, we move that element to the tail
641 * of the sequence with invalid rank as well.
642 * At some point we encounter our original geom and if we stil fail
643 * to assign it a rank, there must be a loop and we fail back to
644 * g_attach() which detach again and calls redo_rank again
645 * to fix up the damage.
646 * It would be much simpler code wise to do it recursively, but we
647 * can't risk that on the kernel stack.
648 */
649
650 static int
651 redo_rank(struct g_geom *gp)
652 {
653 struct g_consumer *cp;
654 struct g_geom *gp1, *gp2;
655 int n, m;
656
657 g_topology_assert();
658 G_VALID_GEOM(gp);
659
660 /* Invalidate this geoms rank and move it to the tail */
661 gp1 = TAILQ_NEXT(gp, geoms);
662 if (gp1 != NULL) {
663 gp->rank = 0;
664 TAILQ_REMOVE(&geoms, gp, geoms);
665 TAILQ_INSERT_TAIL(&geoms, gp, geoms);
666 } else {
667 gp1 = gp;
668 }
669
670 /* re-rank the rest of the sequence */
671 for (; gp1 != NULL; gp1 = gp2) {
672 gp1->rank = 0;
673 m = 1;
674 LIST_FOREACH(cp, &gp1->consumer, consumer) {
675 if (cp->provider == NULL)
676 continue;
677 n = cp->provider->geom->rank;
678 if (n == 0) {
679 m = 0;
680 break;
681 } else if (n >= m)
682 m = n + 1;
683 }
684 gp1->rank = m;
685 gp2 = TAILQ_NEXT(gp1, geoms);
686
687 /* got a rank, moving on */
688 if (m != 0)
689 continue;
690
691 /* no rank to original geom means loop */
692 if (gp == gp1)
693 return (ELOOP);
694
695 /* no rank, put it at the end move on */
696 TAILQ_REMOVE(&geoms, gp1, geoms);
697 TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
698 }
699 return (0);
700 }
701
702 int
703 g_attach(struct g_consumer *cp, struct g_provider *pp)
704 {
705 int error;
706
707 g_topology_assert();
708 G_VALID_CONSUMER(cp);
709 G_VALID_PROVIDER(pp);
710 KASSERT(cp->provider == NULL, ("attach but attached"));
711 cp->provider = pp;
712 LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
713 error = redo_rank(cp->geom);
714 if (error) {
715 LIST_REMOVE(cp, consumers);
716 cp->provider = NULL;
717 redo_rank(cp->geom);
718 }
719 return (error);
720 }
721
722 void
723 g_detach(struct g_consumer *cp)
724 {
725 struct g_provider *pp;
726
727 g_topology_assert();
728 G_VALID_CONSUMER(cp);
729 g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
730 KASSERT(cp->provider != NULL, ("detach but not attached"));
731 KASSERT(cp->acr == 0, ("detach but nonzero acr"));
732 KASSERT(cp->acw == 0, ("detach but nonzero acw"));
733 KASSERT(cp->ace == 0, ("detach but nonzero ace"));
734 KASSERT(cp->nstart == cp->nend,
735 ("detach with active requests"));
736 pp = cp->provider;
737 LIST_REMOVE(cp, consumers);
738 cp->provider = NULL;
739 if (pp->geom->flags & G_GEOM_WITHER)
740 g_do_wither();
741 else if (pp->flags & G_PF_WITHER)
742 g_do_wither();
743 redo_rank(cp->geom);
744 }
745
746 /*
747 * g_access()
748 *
749 * Access-check with delta values. The question asked is "can provider
750 * "cp" change the access counters by the relative amounts dc[rwe] ?"
751 */
752
753 int
754 g_access(struct g_consumer *cp, int dcr, int dcw, int dce)
755 {
756 struct g_provider *pp;
757 int pr,pw,pe;
758 int error;
759
760 g_topology_assert();
761 G_VALID_CONSUMER(cp);
762 pp = cp->provider;
763 KASSERT(pp != NULL, ("access but not attached"));
764 G_VALID_PROVIDER(pp);
765
766 g_trace(G_T_ACCESS, "g_access(%p(%s), %d, %d, %d)",
767 cp, pp->name, dcr, dcw, dce);
768
769 KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
770 KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
771 KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
772 KASSERT(dcr != 0 || dcw != 0 || dce != 0, ("NOP access request"));
773 KASSERT(pp->geom->access != NULL, ("NULL geom->access"));
774
775 /*
776 * If our class cares about being spoiled, and we have been, we
777 * are probably just ahead of the event telling us that. Fail
778 * now rather than having to unravel this later.
779 */
780 if (cp->geom->spoiled != NULL && cp->spoiled &&
781 (dcr > 0 || dcw > 0 || dce > 0))
782 return (ENXIO);
783
784 /*
785 * Figure out what counts the provider would have had, if this
786 * consumer had (r0w0e0) at this time.
787 */
788 pr = pp->acr - cp->acr;
789 pw = pp->acw - cp->acw;
790 pe = pp->ace - cp->ace;
791
792 g_trace(G_T_ACCESS,
793 "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
794 dcr, dcw, dce,
795 cp->acr, cp->acw, cp->ace,
796 pp->acr, pp->acw, pp->ace,
797 pp, pp->name);
798
799 /* If foot-shooting is enabled, any open on rank#1 is OK */
800 if ((g_debugflags & 16) && pp->geom->rank == 1)
801 ;
802 /* If we try exclusive but already write: fail */
803 else if (dce > 0 && pw > 0)
804 return (EPERM);
805 /* If we try write but already exclusive: fail */
806 else if (dcw > 0 && pe > 0)
807 return (EPERM);
808 /* If we try to open more but provider is error'ed: fail */
809 else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0)
810 return (pp->error);
811
812 /* Ok then... */
813
814 error = pp->geom->access(pp, dcr, dcw, dce);
815 KASSERT(dcr > 0 || dcw > 0 || dce > 0 || error == 0,
816 ("Geom provider %s::%s failed closing ->access()",
817 pp->geom->class->name, pp->name));
818 if (!error) {
819 /*
820 * If we open first write, spoil any partner consumers.
821 * If we close last write and provider is not errored,
822 * trigger re-taste.
823 */
824 if (pp->acw == 0 && dcw != 0)
825 g_spoil(pp, cp);
826 else if (pp->acw != 0 && pp->acw == -dcw && pp->error == 0 &&
827 !(pp->geom->flags & G_GEOM_WITHER))
828 g_post_event(g_new_provider_event, pp, M_WAITOK,
829 pp, NULL);
830
831 pp->acr += dcr;
832 pp->acw += dcw;
833 pp->ace += dce;
834 cp->acr += dcr;
835 cp->acw += dcw;
836 cp->ace += dce;
837 if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)
838 KASSERT(pp->sectorsize > 0,
839 ("Provider %s lacks sectorsize", pp->name));
840 }
841 return (error);
842 }
843
844 int
845 g_handleattr_int(struct bio *bp, const char *attribute, int val)
846 {
847
848 return (g_handleattr(bp, attribute, &val, sizeof val));
849 }
850
851 int
852 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
853 {
854
855 return (g_handleattr(bp, attribute, &val, sizeof val));
856 }
857
858 int
859 g_handleattr_str(struct bio *bp, const char *attribute, const char *str)
860 {
861
862 return (g_handleattr(bp, attribute, str, 0));
863 }
864
865 int
866 g_handleattr(struct bio *bp, const char *attribute, const void *val, int len)
867 {
868 int error = 0;
869
870 if (strcmp(bp->bio_attribute, attribute))
871 return (0);
872 if (len == 0) {
873 bzero(bp->bio_data, bp->bio_length);
874 if (strlcpy(bp->bio_data, val, bp->bio_length) >=
875 bp->bio_length) {
876 printf("%s: %s bio_length %jd len %zu -> EFAULT\n",
877 __func__, bp->bio_to->name,
878 (intmax_t)bp->bio_length, strlen(val));
879 error = EFAULT;
880 }
881 } else if (bp->bio_length == len) {
882 bcopy(val, bp->bio_data, len);
883 } else {
884 printf("%s: %s bio_length %jd len %d -> EFAULT\n", __func__,
885 bp->bio_to->name, (intmax_t)bp->bio_length, len);
886 error = EFAULT;
887 }
888 if (error == 0)
889 bp->bio_completed = bp->bio_length;
890 g_io_deliver(bp, error);
891 return (1);
892 }
893
894 int
895 g_std_access(struct g_provider *pp,
896 int dr __unused, int dw __unused, int de __unused)
897 {
898
899 g_topology_assert();
900 G_VALID_PROVIDER(pp);
901 return (0);
902 }
903
904 void
905 g_std_done(struct bio *bp)
906 {
907 struct bio *bp2;
908
909 bp2 = bp->bio_parent;
910 if (bp2->bio_error == 0)
911 bp2->bio_error = bp->bio_error;
912 bp2->bio_completed += bp->bio_completed;
913 g_destroy_bio(bp);
914 bp2->bio_inbed++;
915 if (bp2->bio_children == bp2->bio_inbed)
916 g_io_deliver(bp2, bp2->bio_error);
917 }
918
919 /* XXX: maybe this is only g_slice_spoiled */
920
921 void
922 g_std_spoiled(struct g_consumer *cp)
923 {
924 struct g_geom *gp;
925 struct g_provider *pp;
926
927 g_topology_assert();
928 G_VALID_CONSUMER(cp);
929 g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
930 g_detach(cp);
931 gp = cp->geom;
932 LIST_FOREACH(pp, &gp->provider, provider)
933 g_orphan_provider(pp, ENXIO);
934 g_destroy_consumer(cp);
935 if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
936 g_destroy_geom(gp);
937 else
938 gp->flags |= G_GEOM_WITHER;
939 }
940
941 /*
942 * Spoiling happens when a provider is opened for writing, but consumers
943 * which are configured by in-band data are attached (slicers for instance).
944 * Since the write might potentially change the in-band data, such consumers
945 * need to re-evaluate their existence after the writing session closes.
946 * We do this by (offering to) tear them down when the open for write happens
947 * in return for a re-taste when it closes again.
948 * Together with the fact that such consumers grab an 'e' bit whenever they
949 * are open, regardless of mode, this ends up DTRT.
950 */
951
952 static void
953 g_spoil_event(void *arg, int flag)
954 {
955 struct g_provider *pp;
956 struct g_consumer *cp, *cp2;
957
958 g_topology_assert();
959 if (flag == EV_CANCEL)
960 return;
961 pp = arg;
962 G_VALID_PROVIDER(pp);
963 for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) {
964 cp2 = LIST_NEXT(cp, consumers);
965 if (!cp->spoiled)
966 continue;
967 cp->spoiled = 0;
968 if (cp->geom->spoiled == NULL)
969 continue;
970 cp->geom->spoiled(cp);
971 g_topology_assert();
972 }
973 }
974
975 void
976 g_spoil(struct g_provider *pp, struct g_consumer *cp)
977 {
978 struct g_consumer *cp2;
979
980 g_topology_assert();
981 G_VALID_PROVIDER(pp);
982 G_VALID_CONSUMER(cp);
983
984 LIST_FOREACH(cp2, &pp->consumers, consumers) {
985 if (cp2 == cp)
986 continue;
987 /*
988 KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
989 KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
990 */
991 KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
992 cp2->spoiled++;
993 }
994 g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL);
995 }
996
997 int
998 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
999 {
1000 int error, i;
1001
1002 i = len;
1003 error = g_io_getattr(attr, cp, &i, var);
1004 if (error)
1005 return (error);
1006 if (i != len)
1007 return (EINVAL);
1008 return (0);
1009 }
1010
1011 #if defined(DIAGNOSTIC) || defined(DDB)
1012 /*
1013 * This function walks (topologically unsafely) the mesh and return a
1014 * non-zero integer if it finds the argument pointer is an object.
1015 * The return value indicates which type of object it is belived to be.
1016 * If topology is not locked, this function is potentially dangerous,
1017 * but since it is for debugging purposes and can be useful for instance
1018 * from DDB, we do not assert topology lock is held.
1019 */
1020 int
1021 g_valid_obj(void const *ptr)
1022 {
1023 struct g_class *mp;
1024 struct g_geom *gp;
1025 struct g_consumer *cp;
1026 struct g_provider *pp;
1027
1028 g_topology_assert();
1029
1030 LIST_FOREACH(mp, &g_classes, class) {
1031 if (ptr == mp)
1032 return (1);
1033 LIST_FOREACH(gp, &mp->geom, geom) {
1034 if (ptr == gp)
1035 return (2);
1036 LIST_FOREACH(cp, &gp->consumer, consumer)
1037 if (ptr == cp)
1038 return (3);
1039 LIST_FOREACH(pp, &gp->provider, provider)
1040 if (ptr == pp)
1041 return (4);
1042 }
1043 }
1044 return(0);
1045 }
1046 #endif
1047
1048 #ifdef DDB
1049
1050 #define gprintf(...) do { \
1051 db_printf("%*s", indent, ""); \
1052 db_printf(__VA_ARGS__); \
1053 } while (0)
1054 #define gprintln(...) do { \
1055 gprintf(__VA_ARGS__); \
1056 db_printf("\n"); \
1057 } while (0)
1058
1059 #define ADDFLAG(obj, flag, sflag) do { \
1060 if ((obj)->flags & (flag)) { \
1061 if (comma) \
1062 strlcat(str, ",", size); \
1063 strlcat(str, (sflag), size); \
1064 comma = 1; \
1065 } \
1066 } while (0)
1067
1068 static char *
1069 provider_flags_to_string(struct g_provider *pp, char *str, size_t size)
1070 {
1071 int comma = 0;
1072
1073 bzero(str, size);
1074 if (pp->flags == 0) {
1075 strlcpy(str, "NONE", size);
1076 return (str);
1077 }
1078 ADDFLAG(pp, G_PF_CANDELETE, "G_PF_CANDELETE");
1079 ADDFLAG(pp, G_PF_WITHER, "G_PF_WITHER");
1080 ADDFLAG(pp, G_PF_ORPHAN, "G_PF_ORPHAN");
1081 return (str);
1082 }
1083
1084 static char *
1085 geom_flags_to_string(struct g_geom *gp, char *str, size_t size)
1086 {
1087 int comma = 0;
1088
1089 bzero(str, size);
1090 if (gp->flags == 0) {
1091 strlcpy(str, "NONE", size);
1092 return (str);
1093 }
1094 ADDFLAG(gp, G_GEOM_WITHER, "G_GEOM_WITHER");
1095 return (str);
1096 }
1097 static void
1098 db_show_geom_consumer(int indent, struct g_consumer *cp)
1099 {
1100
1101 if (indent == 0) {
1102 gprintln("consumer: %p", cp);
1103 gprintln(" class: %s (%p)", cp->geom->class->name,
1104 cp->geom->class);
1105 gprintln(" geom: %s (%p)", cp->geom->name, cp->geom);
1106 if (cp->provider == NULL)
1107 gprintln(" provider: none");
1108 else {
1109 gprintln(" provider: %s (%p)", cp->provider->name,
1110 cp->provider);
1111 }
1112 gprintln(" access: r%dw%de%d", cp->acr, cp->acw, cp->ace);
1113 gprintln(" spoiled: %d", cp->spoiled);
1114 gprintln(" nstart: %u", cp->nstart);
1115 gprintln(" nend: %u", cp->nend);
1116 } else {
1117 gprintf("consumer: %p (%s), access=r%dw%de%d", cp,
1118 cp->provider != NULL ? cp->provider->name : "none",
1119 cp->acr, cp->acw, cp->ace);
1120 if (cp->spoiled)
1121 db_printf(", spoiled=%d", cp->spoiled);
1122 db_printf("\n");
1123 }
1124 }
1125
1126 static void
1127 db_show_geom_provider(int indent, struct g_provider *pp)
1128 {
1129 struct g_consumer *cp;
1130 char flags[64];
1131
1132 if (indent == 0) {
1133 gprintln("provider: %s (%p)", pp->name, pp);
1134 gprintln(" class: %s (%p)", pp->geom->class->name,
1135 pp->geom->class);
1136 gprintln(" geom: %s (%p)", pp->geom->name, pp->geom);
1137 gprintln(" mediasize: %jd", (intmax_t)pp->mediasize);
1138 gprintln(" sectorsize: %u", pp->sectorsize);
1139 gprintln(" stripesize: %u", pp->stripesize);
1140 gprintln(" stripeoffset: %u", pp->stripeoffset);
1141 gprintln(" access: r%dw%de%d", pp->acr, pp->acw,
1142 pp->ace);
1143 gprintln(" flags: %s (0x%04x)",
1144 provider_flags_to_string(pp, flags, sizeof(flags)),
1145 pp->flags);
1146 gprintln(" error: %d", pp->error);
1147 gprintln(" nstart: %u", pp->nstart);
1148 gprintln(" nend: %u", pp->nend);
1149 if (LIST_EMPTY(&pp->consumers))
1150 gprintln(" consumers: none");
1151 } else {
1152 gprintf("provider: %s (%p), access=r%dw%de%d",
1153 pp->name, pp, pp->acr, pp->acw, pp->ace);
1154 if (pp->flags != 0) {
1155 db_printf(", flags=%s (0x%04x)",
1156 provider_flags_to_string(pp, flags, sizeof(flags)),
1157 pp->flags);
1158 }
1159 db_printf("\n");
1160 }
1161 if (!LIST_EMPTY(&pp->consumers)) {
1162 LIST_FOREACH(cp, &pp->consumers, consumers) {
1163 db_show_geom_consumer(indent + 2, cp);
1164 if (db_pager_quit)
1165 break;
1166 }
1167 }
1168 }
1169
1170 static void
1171 db_show_geom_geom(int indent, struct g_geom *gp)
1172 {
1173 struct g_provider *pp;
1174 struct g_consumer *cp;
1175 char flags[64];
1176
1177 if (indent == 0) {
1178 gprintln("geom: %s (%p)", gp->name, gp);
1179 gprintln(" class: %s (%p)", gp->class->name, gp->class);
1180 gprintln(" flags: %s (0x%04x)",
1181 geom_flags_to_string(gp, flags, sizeof(flags)), gp->flags);
1182 gprintln(" rank: %d", gp->rank);
1183 if (LIST_EMPTY(&gp->provider))
1184 gprintln(" providers: none");
1185 if (LIST_EMPTY(&gp->consumer))
1186 gprintln(" consumers: none");
1187 } else {
1188 gprintf("geom: %s (%p), rank=%d", gp->name, gp, gp->rank);
1189 if (gp->flags != 0) {
1190 db_printf(", flags=%s (0x%04x)",
1191 geom_flags_to_string(gp, flags, sizeof(flags)),
1192 gp->flags);
1193 }
1194 db_printf("\n");
1195 }
1196 if (!LIST_EMPTY(&gp->provider)) {
1197 LIST_FOREACH(pp, &gp->provider, provider) {
1198 db_show_geom_provider(indent + 2, pp);
1199 if (db_pager_quit)
1200 break;
1201 }
1202 }
1203 if (!LIST_EMPTY(&gp->consumer)) {
1204 LIST_FOREACH(cp, &gp->consumer, consumer) {
1205 db_show_geom_consumer(indent + 2, cp);
1206 if (db_pager_quit)
1207 break;
1208 }
1209 }
1210 }
1211
1212 static void
1213 db_show_geom_class(struct g_class *mp)
1214 {
1215 struct g_geom *gp;
1216
1217 db_printf("class: %s (%p)\n", mp->name, mp);
1218 LIST_FOREACH(gp, &mp->geom, geom) {
1219 db_show_geom_geom(2, gp);
1220 if (db_pager_quit)
1221 break;
1222 }
1223 }
1224
1225 /*
1226 * Print the GEOM topology or the given object.
1227 */
1228 DB_SHOW_COMMAND(geom, db_show_geom)
1229 {
1230 struct g_class *mp;
1231
1232 if (!have_addr) {
1233 /* No address given, print the entire topology. */
1234 LIST_FOREACH(mp, &g_classes, class) {
1235 db_show_geom_class(mp);
1236 db_printf("\n");
1237 if (db_pager_quit)
1238 break;
1239 }
1240 } else {
1241 switch (g_valid_obj((void *)addr)) {
1242 case 1:
1243 db_show_geom_class((struct g_class *)addr);
1244 break;
1245 case 2:
1246 db_show_geom_geom(0, (struct g_geom *)addr);
1247 break;
1248 case 3:
1249 db_show_geom_consumer(0, (struct g_consumer *)addr);
1250 break;
1251 case 4:
1252 db_show_geom_provider(0, (struct g_provider *)addr);
1253 break;
1254 default:
1255 db_printf("Not a GEOM object.\n");
1256 break;
1257 }
1258 }
1259 }
1260
1261 static void
1262 db_print_bio_cmd(struct bio *bp)
1263 {
1264 db_printf(" cmd: ");
1265 switch (bp->bio_cmd) {
1266 case BIO_READ: db_printf("BIO_READ"); break;
1267 case BIO_WRITE: db_printf("BIO_WRITE"); break;
1268 case BIO_DELETE: db_printf("BIO_DELETE"); break;
1269 case BIO_GETATTR: db_printf("BIO_GETATTR"); break;
1270 case BIO_FLUSH: db_printf("BIO_FLUSH"); break;
1271 case BIO_CMD0: db_printf("BIO_CMD0"); break;
1272 case BIO_CMD1: db_printf("BIO_CMD1"); break;
1273 case BIO_CMD2: db_printf("BIO_CMD2"); break;
1274 default: db_printf("UNKNOWN"); break;
1275 }
1276 db_printf("\n");
1277 }
1278
1279 static void
1280 db_print_bio_flags(struct bio *bp)
1281 {
1282 int comma;
1283
1284 comma = 0;
1285 db_printf(" flags: ");
1286 if (bp->bio_flags & BIO_ERROR) {
1287 db_printf("BIO_ERROR");
1288 comma = 1;
1289 }
1290 if (bp->bio_flags & BIO_DONE) {
1291 db_printf("%sBIO_DONE", (comma ? ", " : ""));
1292 comma = 1;
1293 }
1294 if (bp->bio_flags & BIO_ONQUEUE)
1295 db_printf("%sBIO_ONQUEUE", (comma ? ", " : ""));
1296 db_printf("\n");
1297 }
1298
1299 /*
1300 * Print useful information in a BIO
1301 */
1302 DB_SHOW_COMMAND(bio, db_show_bio)
1303 {
1304 struct bio *bp;
1305
1306 if (have_addr) {
1307 bp = (struct bio *)addr;
1308 db_printf("BIO %p\n", bp);
1309 db_print_bio_cmd(bp);
1310 db_print_bio_flags(bp);
1311 db_printf(" cflags: 0x%hhx\n", bp->bio_cflags);
1312 db_printf(" pflags: 0x%hhx\n", bp->bio_pflags);
1313 db_printf(" offset: %jd\n", (intmax_t)bp->bio_offset);
1314 db_printf(" length: %jd\n", (intmax_t)bp->bio_length);
1315 db_printf(" bcount: %ld\n", bp->bio_bcount);
1316 db_printf(" resid: %ld\n", bp->bio_resid);
1317 db_printf(" completed: %jd\n", (intmax_t)bp->bio_completed);
1318 db_printf(" children: %u\n", bp->bio_children);
1319 db_printf(" inbed: %u\n", bp->bio_inbed);
1320 db_printf(" error: %d\n", bp->bio_error);
1321 db_printf(" parent: %p\n", bp->bio_parent);
1322 db_printf(" driver1: %p\n", bp->bio_driver1);
1323 db_printf(" driver2: %p\n", bp->bio_driver2);
1324 db_printf(" caller1: %p\n", bp->bio_caller1);
1325 db_printf(" caller2: %p\n", bp->bio_caller2);
1326 db_printf(" bio_from: %p\n", bp->bio_from);
1327 db_printf(" bio_to: %p\n", bp->bio_to);
1328 }
1329 }
1330
1331 #undef gprintf
1332 #undef gprintln
1333 #undef ADDFLAG
1334
1335 #endif /* DDB */
Cache object: bb308f60c7e9c7bb280243e98efd5904
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