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/8.1/sys/geom/geom_subr.c 207226 2010-04-26 16:20:18Z jh $");
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 #ifdef KDB
63 #include <sys/kdb.h>
64 #endif
65
66 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
67 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
68 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;
69
70 struct g_hh00 {
71 struct g_class *mp;
72 int error;
73 int post;
74 };
75
76 /*
77 * This event offers a new class a chance to taste all preexisting providers.
78 */
79 static void
80 g_load_class(void *arg, int flag)
81 {
82 struct g_hh00 *hh;
83 struct g_class *mp2, *mp;
84 struct g_geom *gp;
85 struct g_provider *pp;
86
87 g_topology_assert();
88 if (flag == EV_CANCEL) /* XXX: can't happen ? */
89 return;
90 if (g_shutdown)
91 return;
92
93 hh = arg;
94 mp = hh->mp;
95 hh->error = 0;
96 if (hh->post) {
97 g_free(hh);
98 hh = NULL;
99 }
100 g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name);
101 KASSERT(mp->name != NULL && *mp->name != '\0',
102 ("GEOM class has no name"));
103 LIST_FOREACH(mp2, &g_classes, class) {
104 if (mp2 == mp) {
105 printf("The GEOM class %s is already loaded.\n",
106 mp2->name);
107 if (hh != NULL)
108 hh->error = EEXIST;
109 return;
110 } else if (strcmp(mp2->name, mp->name) == 0) {
111 printf("A GEOM class %s is already loaded.\n",
112 mp2->name);
113 if (hh != NULL)
114 hh->error = EEXIST;
115 return;
116 }
117 }
118
119 LIST_INIT(&mp->geom);
120 LIST_INSERT_HEAD(&g_classes, mp, class);
121 if (mp->init != NULL)
122 mp->init(mp);
123 if (mp->taste == NULL)
124 return;
125 LIST_FOREACH(mp2, &g_classes, class) {
126 if (mp == mp2)
127 continue;
128 LIST_FOREACH(gp, &mp2->geom, geom) {
129 LIST_FOREACH(pp, &gp->provider, provider) {
130 mp->taste(mp, pp, 0);
131 g_topology_assert();
132 }
133 }
134 }
135 }
136
137 static void
138 g_unload_class(void *arg, int flag)
139 {
140 struct g_hh00 *hh;
141 struct g_class *mp;
142 struct g_geom *gp;
143 struct g_provider *pp;
144 struct g_consumer *cp;
145 int error;
146
147 g_topology_assert();
148 hh = arg;
149 mp = hh->mp;
150 G_VALID_CLASS(mp);
151 g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name);
152
153 /*
154 * We allow unloading if we have no geoms, or a class
155 * method we can use to get rid of them.
156 */
157 if (!LIST_EMPTY(&mp->geom) && mp->destroy_geom == NULL) {
158 hh->error = EOPNOTSUPP;
159 return;
160 }
161
162 /* We refuse to unload if anything is open */
163 LIST_FOREACH(gp, &mp->geom, geom) {
164 LIST_FOREACH(pp, &gp->provider, provider)
165 if (pp->acr || pp->acw || pp->ace) {
166 hh->error = EBUSY;
167 return;
168 }
169 LIST_FOREACH(cp, &gp->consumer, consumer)
170 if (cp->acr || cp->acw || cp->ace) {
171 hh->error = EBUSY;
172 return;
173 }
174 }
175
176 /* Bar new entries */
177 mp->taste = NULL;
178 mp->config = NULL;
179
180 error = 0;
181 for (;;) {
182 gp = LIST_FIRST(&mp->geom);
183 if (gp == NULL)
184 break;
185 error = mp->destroy_geom(NULL, mp, gp);
186 if (error != 0)
187 break;
188 }
189 if (error == 0) {
190 if (mp->fini != NULL)
191 mp->fini(mp);
192 LIST_REMOVE(mp, class);
193 }
194 hh->error = error;
195 return;
196 }
197
198 int
199 g_modevent(module_t mod, int type, void *data)
200 {
201 struct g_hh00 *hh;
202 int error;
203 static int g_ignition;
204 struct g_class *mp;
205
206 mp = data;
207 if (mp->version != G_VERSION) {
208 printf("GEOM class %s has Wrong version %x\n",
209 mp->name, mp->version);
210 return (EINVAL);
211 }
212 if (!g_ignition) {
213 g_ignition++;
214 g_init();
215 }
216 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
217 hh->mp = data;
218 error = EOPNOTSUPP;
219 switch (type) {
220 case MOD_LOAD:
221 g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", hh->mp->name);
222 /*
223 * Once the system is not cold, MOD_LOAD calls will be
224 * from the userland and the g_event thread will be able
225 * to acknowledge their completion.
226 */
227 if (cold) {
228 hh->post = 1;
229 error = g_post_event(g_load_class, hh, M_WAITOK, NULL);
230 } else {
231 error = g_waitfor_event(g_load_class, hh, M_WAITOK,
232 NULL);
233 if (error == 0)
234 error = hh->error;
235 g_free(hh);
236 }
237 break;
238 case MOD_UNLOAD:
239 g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", hh->mp->name);
240 error = g_waitfor_event(g_unload_class, hh, M_WAITOK, NULL);
241 if (error == 0)
242 error = hh->error;
243 if (error == 0) {
244 KASSERT(LIST_EMPTY(&hh->mp->geom),
245 ("Unloaded class (%s) still has geom", hh->mp->name));
246 }
247 g_free(hh);
248 break;
249 default:
250 g_free(hh);
251 break;
252 }
253 return (error);
254 }
255
256 static void
257 g_retaste_event(void *arg, int flag)
258 {
259 struct g_class *cp, *mp;
260 struct g_geom *gp, *gp2;
261 struct g_hh00 *hh;
262 struct g_provider *pp;
263
264 g_topology_assert();
265 if (flag == EV_CANCEL) /* XXX: can't happen ? */
266 return;
267 if (g_shutdown)
268 return;
269
270 hh = arg;
271 mp = hh->mp;
272 hh->error = 0;
273 if (hh->post) {
274 g_free(hh);
275 hh = NULL;
276 }
277 g_trace(G_T_TOPOLOGY, "g_retaste(%s)", mp->name);
278
279 LIST_FOREACH(cp, &g_classes, class) {
280 LIST_FOREACH(gp, &cp->geom, geom) {
281 LIST_FOREACH(pp, &gp->provider, provider) {
282 if (pp->acr || pp->acw || pp->ace)
283 continue;
284 LIST_FOREACH(gp2, &mp->geom, geom) {
285 if (!strcmp(pp->name, gp2->name))
286 break;
287 }
288 if (gp2 != NULL)
289 g_wither_geom(gp2, ENXIO);
290 mp->taste(mp, pp, 0);
291 g_topology_assert();
292 }
293 }
294 }
295 }
296
297 int
298 g_retaste(struct g_class *mp)
299 {
300 struct g_hh00 *hh;
301 int error;
302
303 if (mp->taste == NULL)
304 return (EINVAL);
305
306 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
307 hh->mp = mp;
308
309 if (cold) {
310 hh->post = 1;
311 error = g_post_event(g_retaste_event, hh, M_WAITOK, NULL);
312 } else {
313 error = g_waitfor_event(g_retaste_event, hh, M_WAITOK, NULL);
314 if (error == 0)
315 error = hh->error;
316 g_free(hh);
317 }
318
319 return (error);
320 }
321
322 struct g_geom *
323 g_new_geomf(struct g_class *mp, const char *fmt, ...)
324 {
325 struct g_geom *gp;
326 va_list ap;
327 struct sbuf *sb;
328
329 g_topology_assert();
330 G_VALID_CLASS(mp);
331 sb = sbuf_new_auto();
332 va_start(ap, fmt);
333 sbuf_vprintf(sb, fmt, ap);
334 va_end(ap);
335 sbuf_finish(sb);
336 gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
337 gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
338 gp->class = mp;
339 gp->rank = 1;
340 LIST_INIT(&gp->consumer);
341 LIST_INIT(&gp->provider);
342 LIST_INSERT_HEAD(&mp->geom, gp, geom);
343 TAILQ_INSERT_HEAD(&geoms, gp, geoms);
344 strcpy(gp->name, sbuf_data(sb));
345 sbuf_delete(sb);
346 /* Fill in defaults from class */
347 gp->start = mp->start;
348 gp->spoiled = mp->spoiled;
349 gp->dumpconf = mp->dumpconf;
350 gp->access = mp->access;
351 gp->orphan = mp->orphan;
352 gp->ioctl = mp->ioctl;
353 return (gp);
354 }
355
356 void
357 g_destroy_geom(struct g_geom *gp)
358 {
359
360 g_topology_assert();
361 G_VALID_GEOM(gp);
362 g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
363 KASSERT(LIST_EMPTY(&gp->consumer),
364 ("g_destroy_geom(%s) with consumer(s) [%p]",
365 gp->name, LIST_FIRST(&gp->consumer)));
366 KASSERT(LIST_EMPTY(&gp->provider),
367 ("g_destroy_geom(%s) with provider(s) [%p]",
368 gp->name, LIST_FIRST(&gp->provider)));
369 g_cancel_event(gp);
370 LIST_REMOVE(gp, geom);
371 TAILQ_REMOVE(&geoms, gp, geoms);
372 g_free(gp->name);
373 g_free(gp);
374 }
375
376 /*
377 * This function is called (repeatedly) until the geom has withered away.
378 */
379 void
380 g_wither_geom(struct g_geom *gp, int error)
381 {
382 struct g_provider *pp;
383
384 g_topology_assert();
385 G_VALID_GEOM(gp);
386 g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name);
387 if (!(gp->flags & G_GEOM_WITHER)) {
388 gp->flags |= G_GEOM_WITHER;
389 LIST_FOREACH(pp, &gp->provider, provider)
390 if (!(pp->flags & G_PF_ORPHAN))
391 g_orphan_provider(pp, error);
392 }
393 g_do_wither();
394 }
395
396 /*
397 * Convenience function to destroy a particular provider.
398 */
399 void
400 g_wither_provider(struct g_provider *pp, int error)
401 {
402
403 pp->flags |= G_PF_WITHER;
404 if (!(pp->flags & G_PF_ORPHAN))
405 g_orphan_provider(pp, error);
406 }
407
408 /*
409 * This function is called (repeatedly) until the has withered away.
410 */
411 void
412 g_wither_geom_close(struct g_geom *gp, int error)
413 {
414 struct g_consumer *cp;
415
416 g_topology_assert();
417 G_VALID_GEOM(gp);
418 g_trace(G_T_TOPOLOGY, "g_wither_geom_close(%p(%s))", gp, gp->name);
419 LIST_FOREACH(cp, &gp->consumer, consumer)
420 if (cp->acr || cp->acw || cp->ace)
421 g_access(cp, -cp->acr, -cp->acw, -cp->ace);
422 g_wither_geom(gp, error);
423 }
424
425 /*
426 * This function is called (repeatedly) until we cant wash away more
427 * withered bits at present. Return value contains two bits. Bit 0
428 * set means "withering stuff we can't wash now", bit 1 means "call
429 * me again, there may be stuff I didn't get the first time around.
430 */
431 int
432 g_wither_washer()
433 {
434 struct g_class *mp;
435 struct g_geom *gp, *gp2;
436 struct g_provider *pp, *pp2;
437 struct g_consumer *cp, *cp2;
438 int result;
439
440 result = 0;
441 g_topology_assert();
442 LIST_FOREACH(mp, &g_classes, class) {
443 LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
444 LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
445 if (!(pp->flags & G_PF_WITHER))
446 continue;
447 if (LIST_EMPTY(&pp->consumers))
448 g_destroy_provider(pp);
449 else
450 result |= 1;
451 }
452 if (!(gp->flags & G_GEOM_WITHER))
453 continue;
454 LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
455 if (LIST_EMPTY(&pp->consumers))
456 g_destroy_provider(pp);
457 else
458 result |= 1;
459 }
460 LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp2) {
461 if (cp->acr || cp->acw || cp->ace) {
462 result |= 1;
463 continue;
464 }
465 if (cp->provider != NULL)
466 g_detach(cp);
467 g_destroy_consumer(cp);
468 result |= 2;
469 }
470 if (LIST_EMPTY(&gp->provider) &&
471 LIST_EMPTY(&gp->consumer))
472 g_destroy_geom(gp);
473 else
474 result |= 1;
475 }
476 }
477 return (result);
478 }
479
480 struct g_consumer *
481 g_new_consumer(struct g_geom *gp)
482 {
483 struct g_consumer *cp;
484
485 g_topology_assert();
486 G_VALID_GEOM(gp);
487 KASSERT(!(gp->flags & G_GEOM_WITHER),
488 ("g_new_consumer on WITHERing geom(%s) (class %s)",
489 gp->name, gp->class->name));
490 KASSERT(gp->orphan != NULL,
491 ("g_new_consumer on geom(%s) (class %s) without orphan",
492 gp->name, gp->class->name));
493
494 cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
495 cp->geom = gp;
496 cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED,
497 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
498 LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
499 return(cp);
500 }
501
502 void
503 g_destroy_consumer(struct g_consumer *cp)
504 {
505 struct g_geom *gp;
506
507 g_topology_assert();
508 G_VALID_CONSUMER(cp);
509 g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
510 KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
511 KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
512 KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
513 KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
514 g_cancel_event(cp);
515 gp = cp->geom;
516 LIST_REMOVE(cp, consumer);
517 devstat_remove_entry(cp->stat);
518 g_free(cp);
519 if (gp->flags & G_GEOM_WITHER)
520 g_do_wither();
521 }
522
523 static void
524 g_new_provider_event(void *arg, int flag)
525 {
526 struct g_class *mp;
527 struct g_provider *pp;
528 struct g_consumer *cp;
529
530 g_topology_assert();
531 if (flag == EV_CANCEL)
532 return;
533 if (g_shutdown)
534 return;
535 pp = arg;
536 G_VALID_PROVIDER(pp);
537 KASSERT(!(pp->flags & G_PF_WITHER),
538 ("g_new_provider_event but withered"));
539 LIST_FOREACH(mp, &g_classes, class) {
540 if (mp->taste == NULL)
541 continue;
542 LIST_FOREACH(cp, &pp->consumers, consumers)
543 if (cp->geom->class == mp)
544 break;
545 if (cp != NULL)
546 continue;
547 mp->taste(mp, pp, 0);
548 g_topology_assert();
549 }
550 }
551
552
553 struct g_provider *
554 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
555 {
556 struct g_provider *pp;
557 struct sbuf *sb;
558 va_list ap;
559
560 g_topology_assert();
561 G_VALID_GEOM(gp);
562 KASSERT(gp->access != NULL,
563 ("new provider on geom(%s) without ->access (class %s)",
564 gp->name, gp->class->name));
565 KASSERT(gp->start != NULL,
566 ("new provider on geom(%s) without ->start (class %s)",
567 gp->name, gp->class->name));
568 KASSERT(!(gp->flags & G_GEOM_WITHER),
569 ("new provider on WITHERing geom(%s) (class %s)",
570 gp->name, gp->class->name));
571 sb = sbuf_new_auto();
572 va_start(ap, fmt);
573 sbuf_vprintf(sb, fmt, ap);
574 va_end(ap);
575 sbuf_finish(sb);
576 pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
577 pp->name = (char *)(pp + 1);
578 strcpy(pp->name, sbuf_data(sb));
579 sbuf_delete(sb);
580 LIST_INIT(&pp->consumers);
581 pp->error = ENXIO;
582 pp->geom = gp;
583 pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED,
584 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
585 LIST_INSERT_HEAD(&gp->provider, pp, provider);
586 g_post_event(g_new_provider_event, pp, M_WAITOK, pp, gp, NULL);
587 return (pp);
588 }
589
590 void
591 g_error_provider(struct g_provider *pp, int error)
592 {
593
594 /* G_VALID_PROVIDER(pp); We may not have g_topology */
595 pp->error = error;
596 }
597
598 struct g_provider *
599 g_provider_by_name(char const *arg)
600 {
601 struct g_class *cp;
602 struct g_geom *gp;
603 struct g_provider *pp;
604
605 LIST_FOREACH(cp, &g_classes, class) {
606 LIST_FOREACH(gp, &cp->geom, geom) {
607 LIST_FOREACH(pp, &gp->provider, provider) {
608 if (!strcmp(arg, pp->name))
609 return (pp);
610 }
611 }
612 }
613 return (NULL);
614 }
615
616 void
617 g_destroy_provider(struct g_provider *pp)
618 {
619 struct g_geom *gp;
620
621 g_topology_assert();
622 G_VALID_PROVIDER(pp);
623 KASSERT(LIST_EMPTY(&pp->consumers),
624 ("g_destroy_provider but attached"));
625 KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
626 KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
627 KASSERT (pp->ace == 0, ("g_destroy_provider with ace"));
628 g_cancel_event(pp);
629 LIST_REMOVE(pp, provider);
630 gp = pp->geom;
631 devstat_remove_entry(pp->stat);
632 g_free(pp);
633 if ((gp->flags & G_GEOM_WITHER))
634 g_do_wither();
635 }
636
637 /*
638 * We keep the "geoms" list sorted by topological order (== increasing
639 * numerical rank) at all times.
640 * When an attach is done, the attaching geoms rank is invalidated
641 * and it is moved to the tail of the list.
642 * All geoms later in the sequence has their ranks reevaluated in
643 * sequence. If we cannot assign rank to a geom because it's
644 * prerequisites do not have rank, we move that element to the tail
645 * of the sequence with invalid rank as well.
646 * At some point we encounter our original geom and if we stil fail
647 * to assign it a rank, there must be a loop and we fail back to
648 * g_attach() which detach again and calls redo_rank again
649 * to fix up the damage.
650 * It would be much simpler code wise to do it recursively, but we
651 * can't risk that on the kernel stack.
652 */
653
654 static int
655 redo_rank(struct g_geom *gp)
656 {
657 struct g_consumer *cp;
658 struct g_geom *gp1, *gp2;
659 int n, m;
660
661 g_topology_assert();
662 G_VALID_GEOM(gp);
663
664 /* Invalidate this geoms rank and move it to the tail */
665 gp1 = TAILQ_NEXT(gp, geoms);
666 if (gp1 != NULL) {
667 gp->rank = 0;
668 TAILQ_REMOVE(&geoms, gp, geoms);
669 TAILQ_INSERT_TAIL(&geoms, gp, geoms);
670 } else {
671 gp1 = gp;
672 }
673
674 /* re-rank the rest of the sequence */
675 for (; gp1 != NULL; gp1 = gp2) {
676 gp1->rank = 0;
677 m = 1;
678 LIST_FOREACH(cp, &gp1->consumer, consumer) {
679 if (cp->provider == NULL)
680 continue;
681 n = cp->provider->geom->rank;
682 if (n == 0) {
683 m = 0;
684 break;
685 } else if (n >= m)
686 m = n + 1;
687 }
688 gp1->rank = m;
689 gp2 = TAILQ_NEXT(gp1, geoms);
690
691 /* got a rank, moving on */
692 if (m != 0)
693 continue;
694
695 /* no rank to original geom means loop */
696 if (gp == gp1)
697 return (ELOOP);
698
699 /* no rank, put it at the end move on */
700 TAILQ_REMOVE(&geoms, gp1, geoms);
701 TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
702 }
703 return (0);
704 }
705
706 int
707 g_attach(struct g_consumer *cp, struct g_provider *pp)
708 {
709 int error;
710
711 g_topology_assert();
712 G_VALID_CONSUMER(cp);
713 G_VALID_PROVIDER(pp);
714 KASSERT(cp->provider == NULL, ("attach but attached"));
715 cp->provider = pp;
716 LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
717 error = redo_rank(cp->geom);
718 if (error) {
719 LIST_REMOVE(cp, consumers);
720 cp->provider = NULL;
721 redo_rank(cp->geom);
722 }
723 return (error);
724 }
725
726 void
727 g_detach(struct g_consumer *cp)
728 {
729 struct g_provider *pp;
730
731 g_topology_assert();
732 G_VALID_CONSUMER(cp);
733 g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
734 KASSERT(cp->provider != NULL, ("detach but not attached"));
735 KASSERT(cp->acr == 0, ("detach but nonzero acr"));
736 KASSERT(cp->acw == 0, ("detach but nonzero acw"));
737 KASSERT(cp->ace == 0, ("detach but nonzero ace"));
738 KASSERT(cp->nstart == cp->nend,
739 ("detach with active requests"));
740 pp = cp->provider;
741 LIST_REMOVE(cp, consumers);
742 cp->provider = NULL;
743 if (pp->geom->flags & G_GEOM_WITHER)
744 g_do_wither();
745 else if (pp->flags & G_PF_WITHER)
746 g_do_wither();
747 redo_rank(cp->geom);
748 }
749
750 /*
751 * g_access()
752 *
753 * Access-check with delta values. The question asked is "can provider
754 * "cp" change the access counters by the relative amounts dc[rwe] ?"
755 */
756
757 int
758 g_access(struct g_consumer *cp, int dcr, int dcw, int dce)
759 {
760 struct g_provider *pp;
761 int pr,pw,pe;
762 int error;
763
764 g_topology_assert();
765 G_VALID_CONSUMER(cp);
766 pp = cp->provider;
767 KASSERT(pp != NULL, ("access but not attached"));
768 G_VALID_PROVIDER(pp);
769
770 g_trace(G_T_ACCESS, "g_access(%p(%s), %d, %d, %d)",
771 cp, pp->name, dcr, dcw, dce);
772
773 KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
774 KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
775 KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
776 KASSERT(dcr != 0 || dcw != 0 || dce != 0, ("NOP access request"));
777 KASSERT(pp->geom->access != NULL, ("NULL geom->access"));
778
779 /*
780 * If our class cares about being spoiled, and we have been, we
781 * are probably just ahead of the event telling us that. Fail
782 * now rather than having to unravel this later.
783 */
784 if (cp->geom->spoiled != NULL && cp->spoiled &&
785 (dcr > 0 || dcw > 0 || dce > 0))
786 return (ENXIO);
787
788 /*
789 * Figure out what counts the provider would have had, if this
790 * consumer had (r0w0e0) at this time.
791 */
792 pr = pp->acr - cp->acr;
793 pw = pp->acw - cp->acw;
794 pe = pp->ace - cp->ace;
795
796 g_trace(G_T_ACCESS,
797 "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
798 dcr, dcw, dce,
799 cp->acr, cp->acw, cp->ace,
800 pp->acr, pp->acw, pp->ace,
801 pp, pp->name);
802
803 /* If foot-shooting is enabled, any open on rank#1 is OK */
804 if ((g_debugflags & 16) && pp->geom->rank == 1)
805 ;
806 /* If we try exclusive but already write: fail */
807 else if (dce > 0 && pw > 0)
808 return (EPERM);
809 /* If we try write but already exclusive: fail */
810 else if (dcw > 0 && pe > 0)
811 return (EPERM);
812 /* If we try to open more but provider is error'ed: fail */
813 else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0)
814 return (pp->error);
815
816 /* Ok then... */
817
818 error = pp->geom->access(pp, dcr, dcw, dce);
819 KASSERT(dcr > 0 || dcw > 0 || dce > 0 || error == 0,
820 ("Geom provider %s::%s failed closing ->access()",
821 pp->geom->class->name, pp->name));
822 if (!error) {
823 /*
824 * If we open first write, spoil any partner consumers.
825 * If we close last write and provider is not errored,
826 * trigger re-taste.
827 */
828 if (pp->acw == 0 && dcw != 0)
829 g_spoil(pp, cp);
830 else if (pp->acw != 0 && pp->acw == -dcw && pp->error == 0 &&
831 !(pp->geom->flags & G_GEOM_WITHER))
832 g_post_event(g_new_provider_event, pp, M_WAITOK,
833 pp, NULL);
834
835 pp->acr += dcr;
836 pp->acw += dcw;
837 pp->ace += dce;
838 cp->acr += dcr;
839 cp->acw += dcw;
840 cp->ace += dce;
841 if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)
842 KASSERT(pp->sectorsize > 0,
843 ("Provider %s lacks sectorsize", pp->name));
844 }
845 return (error);
846 }
847
848 int
849 g_handleattr_int(struct bio *bp, const char *attribute, int val)
850 {
851
852 return (g_handleattr(bp, attribute, &val, sizeof val));
853 }
854
855 int
856 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
857 {
858
859 return (g_handleattr(bp, attribute, &val, sizeof val));
860 }
861
862 int
863 g_handleattr_str(struct bio *bp, const char *attribute, const char *str)
864 {
865
866 return (g_handleattr(bp, attribute, str, 0));
867 }
868
869 int
870 g_handleattr(struct bio *bp, const char *attribute, const void *val, int len)
871 {
872 int error = 0;
873
874 if (strcmp(bp->bio_attribute, attribute))
875 return (0);
876 if (len == 0) {
877 bzero(bp->bio_data, bp->bio_length);
878 if (strlcpy(bp->bio_data, val, bp->bio_length) >=
879 bp->bio_length) {
880 printf("%s: %s bio_length %jd len %zu -> EFAULT\n",
881 __func__, bp->bio_to->name,
882 (intmax_t)bp->bio_length, strlen(val));
883 error = EFAULT;
884 }
885 } else if (bp->bio_length == len) {
886 bcopy(val, bp->bio_data, len);
887 } else {
888 printf("%s: %s bio_length %jd len %d -> EFAULT\n", __func__,
889 bp->bio_to->name, (intmax_t)bp->bio_length, len);
890 error = EFAULT;
891 }
892 if (error == 0)
893 bp->bio_completed = bp->bio_length;
894 g_io_deliver(bp, error);
895 return (1);
896 }
897
898 int
899 g_std_access(struct g_provider *pp,
900 int dr __unused, int dw __unused, int de __unused)
901 {
902
903 g_topology_assert();
904 G_VALID_PROVIDER(pp);
905 return (0);
906 }
907
908 void
909 g_std_done(struct bio *bp)
910 {
911 struct bio *bp2;
912
913 bp2 = bp->bio_parent;
914 if (bp2->bio_error == 0)
915 bp2->bio_error = bp->bio_error;
916 bp2->bio_completed += bp->bio_completed;
917 g_destroy_bio(bp);
918 bp2->bio_inbed++;
919 if (bp2->bio_children == bp2->bio_inbed)
920 g_io_deliver(bp2, bp2->bio_error);
921 }
922
923 /* XXX: maybe this is only g_slice_spoiled */
924
925 void
926 g_std_spoiled(struct g_consumer *cp)
927 {
928 struct g_geom *gp;
929 struct g_provider *pp;
930
931 g_topology_assert();
932 G_VALID_CONSUMER(cp);
933 g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
934 g_detach(cp);
935 gp = cp->geom;
936 LIST_FOREACH(pp, &gp->provider, provider)
937 g_orphan_provider(pp, ENXIO);
938 g_destroy_consumer(cp);
939 if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
940 g_destroy_geom(gp);
941 else
942 gp->flags |= G_GEOM_WITHER;
943 }
944
945 /*
946 * Spoiling happens when a provider is opened for writing, but consumers
947 * which are configured by in-band data are attached (slicers for instance).
948 * Since the write might potentially change the in-band data, such consumers
949 * need to re-evaluate their existence after the writing session closes.
950 * We do this by (offering to) tear them down when the open for write happens
951 * in return for a re-taste when it closes again.
952 * Together with the fact that such consumers grab an 'e' bit whenever they
953 * are open, regardless of mode, this ends up DTRT.
954 */
955
956 static void
957 g_spoil_event(void *arg, int flag)
958 {
959 struct g_provider *pp;
960 struct g_consumer *cp, *cp2;
961
962 g_topology_assert();
963 if (flag == EV_CANCEL)
964 return;
965 pp = arg;
966 G_VALID_PROVIDER(pp);
967 for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) {
968 cp2 = LIST_NEXT(cp, consumers);
969 if (!cp->spoiled)
970 continue;
971 cp->spoiled = 0;
972 if (cp->geom->spoiled == NULL)
973 continue;
974 cp->geom->spoiled(cp);
975 g_topology_assert();
976 }
977 }
978
979 void
980 g_spoil(struct g_provider *pp, struct g_consumer *cp)
981 {
982 struct g_consumer *cp2;
983
984 g_topology_assert();
985 G_VALID_PROVIDER(pp);
986 G_VALID_CONSUMER(cp);
987
988 LIST_FOREACH(cp2, &pp->consumers, consumers) {
989 if (cp2 == cp)
990 continue;
991 /*
992 KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
993 KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
994 */
995 KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
996 cp2->spoiled++;
997 }
998 g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL);
999 }
1000
1001 int
1002 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
1003 {
1004 int error, i;
1005
1006 i = len;
1007 error = g_io_getattr(attr, cp, &i, var);
1008 if (error)
1009 return (error);
1010 if (i != len)
1011 return (EINVAL);
1012 return (0);
1013 }
1014
1015 #if defined(DIAGNOSTIC) || defined(DDB)
1016 /*
1017 * This function walks the mesh and returns a non-zero integer if it
1018 * finds the argument pointer is an object. The return value indicates
1019 * which type of object it is believed to be. If topology is not locked,
1020 * this function is potentially dangerous, but we don't assert that the
1021 * topology lock is held when called from debugger.
1022 */
1023 int
1024 g_valid_obj(void const *ptr)
1025 {
1026 struct g_class *mp;
1027 struct g_geom *gp;
1028 struct g_consumer *cp;
1029 struct g_provider *pp;
1030
1031 #ifdef KDB
1032 if (kdb_active == 0)
1033 #endif
1034 g_topology_assert();
1035
1036 LIST_FOREACH(mp, &g_classes, class) {
1037 if (ptr == mp)
1038 return (1);
1039 LIST_FOREACH(gp, &mp->geom, geom) {
1040 if (ptr == gp)
1041 return (2);
1042 LIST_FOREACH(cp, &gp->consumer, consumer)
1043 if (ptr == cp)
1044 return (3);
1045 LIST_FOREACH(pp, &gp->provider, provider)
1046 if (ptr == pp)
1047 return (4);
1048 }
1049 }
1050 return(0);
1051 }
1052 #endif
1053
1054 #ifdef DDB
1055
1056 #define gprintf(...) do { \
1057 db_printf("%*s", indent, ""); \
1058 db_printf(__VA_ARGS__); \
1059 } while (0)
1060 #define gprintln(...) do { \
1061 gprintf(__VA_ARGS__); \
1062 db_printf("\n"); \
1063 } while (0)
1064
1065 #define ADDFLAG(obj, flag, sflag) do { \
1066 if ((obj)->flags & (flag)) { \
1067 if (comma) \
1068 strlcat(str, ",", size); \
1069 strlcat(str, (sflag), size); \
1070 comma = 1; \
1071 } \
1072 } while (0)
1073
1074 static char *
1075 provider_flags_to_string(struct g_provider *pp, char *str, size_t size)
1076 {
1077 int comma = 0;
1078
1079 bzero(str, size);
1080 if (pp->flags == 0) {
1081 strlcpy(str, "NONE", size);
1082 return (str);
1083 }
1084 ADDFLAG(pp, G_PF_CANDELETE, "G_PF_CANDELETE");
1085 ADDFLAG(pp, G_PF_WITHER, "G_PF_WITHER");
1086 ADDFLAG(pp, G_PF_ORPHAN, "G_PF_ORPHAN");
1087 return (str);
1088 }
1089
1090 static char *
1091 geom_flags_to_string(struct g_geom *gp, char *str, size_t size)
1092 {
1093 int comma = 0;
1094
1095 bzero(str, size);
1096 if (gp->flags == 0) {
1097 strlcpy(str, "NONE", size);
1098 return (str);
1099 }
1100 ADDFLAG(gp, G_GEOM_WITHER, "G_GEOM_WITHER");
1101 return (str);
1102 }
1103 static void
1104 db_show_geom_consumer(int indent, struct g_consumer *cp)
1105 {
1106
1107 if (indent == 0) {
1108 gprintln("consumer: %p", cp);
1109 gprintln(" class: %s (%p)", cp->geom->class->name,
1110 cp->geom->class);
1111 gprintln(" geom: %s (%p)", cp->geom->name, cp->geom);
1112 if (cp->provider == NULL)
1113 gprintln(" provider: none");
1114 else {
1115 gprintln(" provider: %s (%p)", cp->provider->name,
1116 cp->provider);
1117 }
1118 gprintln(" access: r%dw%de%d", cp->acr, cp->acw, cp->ace);
1119 gprintln(" spoiled: %d", cp->spoiled);
1120 gprintln(" nstart: %u", cp->nstart);
1121 gprintln(" nend: %u", cp->nend);
1122 } else {
1123 gprintf("consumer: %p (%s), access=r%dw%de%d", cp,
1124 cp->provider != NULL ? cp->provider->name : "none",
1125 cp->acr, cp->acw, cp->ace);
1126 if (cp->spoiled)
1127 db_printf(", spoiled=%d", cp->spoiled);
1128 db_printf("\n");
1129 }
1130 }
1131
1132 static void
1133 db_show_geom_provider(int indent, struct g_provider *pp)
1134 {
1135 struct g_consumer *cp;
1136 char flags[64];
1137
1138 if (indent == 0) {
1139 gprintln("provider: %s (%p)", pp->name, pp);
1140 gprintln(" class: %s (%p)", pp->geom->class->name,
1141 pp->geom->class);
1142 gprintln(" geom: %s (%p)", pp->geom->name, pp->geom);
1143 gprintln(" mediasize: %jd", (intmax_t)pp->mediasize);
1144 gprintln(" sectorsize: %u", pp->sectorsize);
1145 gprintln(" stripesize: %u", pp->stripesize);
1146 gprintln(" stripeoffset: %u", pp->stripeoffset);
1147 gprintln(" access: r%dw%de%d", pp->acr, pp->acw,
1148 pp->ace);
1149 gprintln(" flags: %s (0x%04x)",
1150 provider_flags_to_string(pp, flags, sizeof(flags)),
1151 pp->flags);
1152 gprintln(" error: %d", pp->error);
1153 gprintln(" nstart: %u", pp->nstart);
1154 gprintln(" nend: %u", pp->nend);
1155 if (LIST_EMPTY(&pp->consumers))
1156 gprintln(" consumers: none");
1157 } else {
1158 gprintf("provider: %s (%p), access=r%dw%de%d",
1159 pp->name, pp, pp->acr, pp->acw, pp->ace);
1160 if (pp->flags != 0) {
1161 db_printf(", flags=%s (0x%04x)",
1162 provider_flags_to_string(pp, flags, sizeof(flags)),
1163 pp->flags);
1164 }
1165 db_printf("\n");
1166 }
1167 if (!LIST_EMPTY(&pp->consumers)) {
1168 LIST_FOREACH(cp, &pp->consumers, consumers) {
1169 db_show_geom_consumer(indent + 2, cp);
1170 if (db_pager_quit)
1171 break;
1172 }
1173 }
1174 }
1175
1176 static void
1177 db_show_geom_geom(int indent, struct g_geom *gp)
1178 {
1179 struct g_provider *pp;
1180 struct g_consumer *cp;
1181 char flags[64];
1182
1183 if (indent == 0) {
1184 gprintln("geom: %s (%p)", gp->name, gp);
1185 gprintln(" class: %s (%p)", gp->class->name, gp->class);
1186 gprintln(" flags: %s (0x%04x)",
1187 geom_flags_to_string(gp, flags, sizeof(flags)), gp->flags);
1188 gprintln(" rank: %d", gp->rank);
1189 if (LIST_EMPTY(&gp->provider))
1190 gprintln(" providers: none");
1191 if (LIST_EMPTY(&gp->consumer))
1192 gprintln(" consumers: none");
1193 } else {
1194 gprintf("geom: %s (%p), rank=%d", gp->name, gp, gp->rank);
1195 if (gp->flags != 0) {
1196 db_printf(", flags=%s (0x%04x)",
1197 geom_flags_to_string(gp, flags, sizeof(flags)),
1198 gp->flags);
1199 }
1200 db_printf("\n");
1201 }
1202 if (!LIST_EMPTY(&gp->provider)) {
1203 LIST_FOREACH(pp, &gp->provider, provider) {
1204 db_show_geom_provider(indent + 2, pp);
1205 if (db_pager_quit)
1206 break;
1207 }
1208 }
1209 if (!LIST_EMPTY(&gp->consumer)) {
1210 LIST_FOREACH(cp, &gp->consumer, consumer) {
1211 db_show_geom_consumer(indent + 2, cp);
1212 if (db_pager_quit)
1213 break;
1214 }
1215 }
1216 }
1217
1218 static void
1219 db_show_geom_class(struct g_class *mp)
1220 {
1221 struct g_geom *gp;
1222
1223 db_printf("class: %s (%p)\n", mp->name, mp);
1224 LIST_FOREACH(gp, &mp->geom, geom) {
1225 db_show_geom_geom(2, gp);
1226 if (db_pager_quit)
1227 break;
1228 }
1229 }
1230
1231 /*
1232 * Print the GEOM topology or the given object.
1233 */
1234 DB_SHOW_COMMAND(geom, db_show_geom)
1235 {
1236 struct g_class *mp;
1237
1238 if (!have_addr) {
1239 /* No address given, print the entire topology. */
1240 LIST_FOREACH(mp, &g_classes, class) {
1241 db_show_geom_class(mp);
1242 db_printf("\n");
1243 if (db_pager_quit)
1244 break;
1245 }
1246 } else {
1247 switch (g_valid_obj((void *)addr)) {
1248 case 1:
1249 db_show_geom_class((struct g_class *)addr);
1250 break;
1251 case 2:
1252 db_show_geom_geom(0, (struct g_geom *)addr);
1253 break;
1254 case 3:
1255 db_show_geom_consumer(0, (struct g_consumer *)addr);
1256 break;
1257 case 4:
1258 db_show_geom_provider(0, (struct g_provider *)addr);
1259 break;
1260 default:
1261 db_printf("Not a GEOM object.\n");
1262 break;
1263 }
1264 }
1265 }
1266
1267 static void
1268 db_print_bio_cmd(struct bio *bp)
1269 {
1270 db_printf(" cmd: ");
1271 switch (bp->bio_cmd) {
1272 case BIO_READ: db_printf("BIO_READ"); break;
1273 case BIO_WRITE: db_printf("BIO_WRITE"); break;
1274 case BIO_DELETE: db_printf("BIO_DELETE"); break;
1275 case BIO_GETATTR: db_printf("BIO_GETATTR"); break;
1276 case BIO_FLUSH: db_printf("BIO_FLUSH"); break;
1277 case BIO_CMD0: db_printf("BIO_CMD0"); break;
1278 case BIO_CMD1: db_printf("BIO_CMD1"); break;
1279 case BIO_CMD2: db_printf("BIO_CMD2"); break;
1280 default: db_printf("UNKNOWN"); break;
1281 }
1282 db_printf("\n");
1283 }
1284
1285 static void
1286 db_print_bio_flags(struct bio *bp)
1287 {
1288 int comma;
1289
1290 comma = 0;
1291 db_printf(" flags: ");
1292 if (bp->bio_flags & BIO_ERROR) {
1293 db_printf("BIO_ERROR");
1294 comma = 1;
1295 }
1296 if (bp->bio_flags & BIO_DONE) {
1297 db_printf("%sBIO_DONE", (comma ? ", " : ""));
1298 comma = 1;
1299 }
1300 if (bp->bio_flags & BIO_ONQUEUE)
1301 db_printf("%sBIO_ONQUEUE", (comma ? ", " : ""));
1302 db_printf("\n");
1303 }
1304
1305 /*
1306 * Print useful information in a BIO
1307 */
1308 DB_SHOW_COMMAND(bio, db_show_bio)
1309 {
1310 struct bio *bp;
1311
1312 if (have_addr) {
1313 bp = (struct bio *)addr;
1314 db_printf("BIO %p\n", bp);
1315 db_print_bio_cmd(bp);
1316 db_print_bio_flags(bp);
1317 db_printf(" cflags: 0x%hhx\n", bp->bio_cflags);
1318 db_printf(" pflags: 0x%hhx\n", bp->bio_pflags);
1319 db_printf(" offset: %jd\n", (intmax_t)bp->bio_offset);
1320 db_printf(" length: %jd\n", (intmax_t)bp->bio_length);
1321 db_printf(" bcount: %ld\n", bp->bio_bcount);
1322 db_printf(" resid: %ld\n", bp->bio_resid);
1323 db_printf(" completed: %jd\n", (intmax_t)bp->bio_completed);
1324 db_printf(" children: %u\n", bp->bio_children);
1325 db_printf(" inbed: %u\n", bp->bio_inbed);
1326 db_printf(" error: %d\n", bp->bio_error);
1327 db_printf(" parent: %p\n", bp->bio_parent);
1328 db_printf(" driver1: %p\n", bp->bio_driver1);
1329 db_printf(" driver2: %p\n", bp->bio_driver2);
1330 db_printf(" caller1: %p\n", bp->bio_caller1);
1331 db_printf(" caller2: %p\n", bp->bio_caller2);
1332 db_printf(" bio_from: %p\n", bp->bio_from);
1333 db_printf(" bio_to: %p\n", bp->bio_to);
1334 }
1335 }
1336
1337 #undef gprintf
1338 #undef gprintln
1339 #undef ADDFLAG
1340
1341 #endif /* DDB */
Cache object: 1ae6b9ce81757c2d7cca8b34cd7f05b6
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