Super User's BSD Cross Reference: /FreeBSD/sys/geom/geom_subr.c

 /*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2002 Poul-Henning Kamp
 * Copyright (c) 2002 Networks Associates Technology, Inc.
 * All rights reserved.
 *
 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
 * and NAI Labs, the Security Research Division of Network Associates, Inc.
 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
 * DARPA CHATS research program.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 3. The names of the authors may not be used to endorse or promote
 * products derived from this software without specific prior written
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");

#include "opt_ddb.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/devicestat.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/errno.h>
#include <sys/sbuf.h>
#include <sys/sdt.h>
#include <geom/geom.h>
#include <geom/geom_dbg.h>
#include <geom/geom_int.h>
#include <machine/stdarg.h>

#ifdef DDB
#include <ddb/ddb.h>
#endif

#ifdef KDB
#include <sys/kdb.h>
#endif

 SDT_PROVIDER_DEFINE(geom);

 struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes);
 static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms);
 char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim;

 struct g_hh00 {
 struct g_class *mp;
 struct g_provider *pp;
 off_t size;
 int error;
 int post;
};

 void
 g_dbg_printf(const char *classname, int lvl, struct bio *bp,
 const char *format,
 ...)
{
#ifndef PRINTF_BUFR_SIZE
#define PRINTF_BUFR_SIZE 64
#endif
 char bufr[PRINTF_BUFR_SIZE];
 struct sbuf sb, *sbp __unused;
 va_list ap;

 sbp = sbuf_new(&sb, bufr, sizeof(bufr), SBUF_FIXEDLEN);
 KASSERT(sbp != NULL, ("sbuf_new misused?"));

 sbuf_set_drain(&sb, sbuf_printf_drain, NULL);

 sbuf_cat(&sb, classname);
 if (lvl >= 0)
 sbuf_printf(&sb, "[%d]", lvl);

 va_start(ap, format);
 sbuf_vprintf(&sb, format, ap);
 va_end(ap);

 if (bp != NULL) {
 sbuf_putc(&sb, ' ');
 g_format_bio(&sb, bp);
 }

 /* Terminate the debug line with a single '\n'. */
 sbuf_nl_terminate(&sb);

 /* Flush line to printf. */
 sbuf_finish(&sb);
 sbuf_delete(&sb);
}

 /*
 * This event offers a new class a chance to taste all preexisting providers.
 */
 static void
 g_load_class(void *arg, int flag)
{
 struct g_hh00 *hh;
 struct g_class *mp2, *mp;
 struct g_geom *gp;
 struct g_provider *pp;

 g_topology_assert();
 if (flag == EV_CANCEL) /* XXX: can't happen ? */
 return;
 if (g_shutdown)
 return;

 hh = arg;
 mp = hh->mp;
 hh->error = 0;
 if (hh->post) {
 g_free(hh);
 hh = NULL;
 }
 g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name);
 KASSERT(mp->name != NULL && *mp->name != '0円',
 ("GEOM class has no name"));
 LIST_FOREACH(mp2, &g_classes, class) {
 if (mp2 == mp) {
 printf("The GEOM class %s is already loaded.\n",
 mp2->name);
 if (hh != NULL)
 hh->error = EEXIST;
 return;
 } else if (strcmp(mp2->name, mp->name) == 0) {
 printf("A GEOM class %s is already loaded.\n",
 mp2->name);
 if (hh != NULL)
 hh->error = EEXIST;
 return;
 }
 }

 LIST_INIT(&mp->geom);
 LIST_INSERT_HEAD(&g_classes, mp, class);
 if (mp->init != NULL)
 mp->init(mp);
 if (mp->taste == NULL)
 return;
 LIST_FOREACH(mp2, &g_classes, class) {
 if (mp == mp2)
 continue;
 LIST_FOREACH(gp, &mp2->geom, geom) {
 LIST_FOREACH(pp, &gp->provider, provider) {
 mp->taste(mp, pp, 0);
 g_topology_assert();
 }
 }
 }
}

 static int
 g_unload_class(struct g_class *mp)
{
 struct g_geom *gp;
 struct g_provider *pp;
 struct g_consumer *cp;
 int error;

 g_topology_lock();
 g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name);
 retry:
 G_VALID_CLASS(mp);
 LIST_FOREACH(gp, &mp->geom, geom) {
 /* We refuse to unload if anything is open */
 LIST_FOREACH(pp, &gp->provider, provider)
 if (pp->acr || pp->acw || pp->ace) {
 g_topology_unlock();
 return (EBUSY);
 }
 LIST_FOREACH(cp, &gp->consumer, consumer)
 if (cp->acr || cp->acw || cp->ace) {
 g_topology_unlock();
 return (EBUSY);
 }
 /* If the geom is withering, wait for it to finish. */
 if (gp->flags & G_GEOM_WITHER) {
 g_topology_sleep(mp, 1);
 goto retry;
 }
 }

 /*
 * We allow unloading if we have no geoms, or a class
 * method we can use to get rid of them.
 */
 if (!LIST_EMPTY(&mp->geom) && mp->destroy_geom == NULL) {
 g_topology_unlock();
 return (EOPNOTSUPP);
 }

 /* Bar new entries */
 mp->taste = NULL;
 mp->config = NULL;

 LIST_FOREACH(gp, &mp->geom, geom) {
 error = mp->destroy_geom(NULL, mp, gp);
 if (error != 0) {
 g_topology_unlock();
 return (error);
 }
 }
 /* Wait for withering to finish. */
 for (;;) {
 gp = LIST_FIRST(&mp->geom);
 if (gp == NULL)
 break;
 KASSERT(gp->flags & G_GEOM_WITHER,
 ("Non-withering geom in class %s", mp->name));
 g_topology_sleep(mp, 1);
 }
 G_VALID_CLASS(mp);
 if (mp->fini != NULL)
 mp->fini(mp);
 LIST_REMOVE(mp, class);
 g_topology_unlock();

 return (0);
}

 int
 g_modevent(module_t mod, int type, void *data)
{
 struct g_hh00 *hh;
 int error;
 static int g_ignition;
 struct g_class *mp;

 mp = data;
 if (mp->version != G_VERSION) {
 printf("GEOM class %s has Wrong version %x\n",
 mp->name, mp->version);
 return (EINVAL);
 }
 if (!g_ignition) {
 g_ignition++;
 g_init();
 }
 error = EOPNOTSUPP;
 switch (type) {
 case MOD_LOAD:
 g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", mp->name);
 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
 hh->mp = mp;
 /*
 * Once the system is not cold, MOD_LOAD calls will be
 * from the userland and the g_event thread will be able
 * to acknowledge their completion.
 */
 if (cold) {
 hh->post = 1;
 error = g_post_event(g_load_class, hh, M_WAITOK, NULL);
 } else {
 error = g_waitfor_event(g_load_class, hh, M_WAITOK,
 NULL);
 if (error == 0)
 error = hh->error;
 g_free(hh);
 }
 break;
 case MOD_UNLOAD:
 g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", mp->name);
 error = g_unload_class(mp);
 if (error == 0) {
 KASSERT(LIST_EMPTY(&mp->geom),
 ("Unloaded class (%s) still has geom", mp->name));
 }
 break;
 }
 return (error);
}

 static void
 g_retaste_event(void *arg, int flag)
{
 struct g_class *mp, *mp2;
 struct g_geom *gp;
 struct g_hh00 *hh;
 struct g_provider *pp;
 struct g_consumer *cp;

 g_topology_assert();
 if (flag == EV_CANCEL) /* XXX: can't happen ? */
 return;
 if (g_shutdown || g_notaste)
 return;

 hh = arg;
 mp = hh->mp;
 hh->error = 0;
 if (hh->post) {
 g_free(hh);
 hh = NULL;
 }
 g_trace(G_T_TOPOLOGY, "g_retaste(%s)", mp->name);

 LIST_FOREACH(mp2, &g_classes, class) {
 LIST_FOREACH(gp, &mp2->geom, geom) {
 LIST_FOREACH(pp, &gp->provider, provider) {
 if (pp->acr || pp->acw || pp->ace)
 continue;
 LIST_FOREACH(cp, &pp->consumers, consumers) {
 if (cp->geom->class == mp &&
 (cp->flags & G_CF_ORPHAN) == 0)
 break;
 }
 if (cp != NULL) {
 cp->flags |= G_CF_ORPHAN;
 g_wither_geom(cp->geom, ENXIO);
 }
 mp->taste(mp, pp, 0);
 g_topology_assert();
 }
 }
 }
}

 int
 g_retaste(struct g_class *mp)
{
 struct g_hh00 *hh;
 int error;

 if (mp->taste == NULL)
 return (EINVAL);

 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
 hh->mp = mp;

 if (cold) {
 hh->post = 1;
 error = g_post_event(g_retaste_event, hh, M_WAITOK, NULL);
 } else {
 error = g_waitfor_event(g_retaste_event, hh, M_WAITOK, NULL);
 if (error == 0)
 error = hh->error;
 g_free(hh);
 }

 return (error);
}

 struct g_geom *
 g_new_geomf(struct g_class *mp, const char *fmt, ...)
{
 struct g_geom *gp;
 va_list ap;
 struct sbuf *sb;

 g_topology_assert();
 G_VALID_CLASS(mp);
 sb = sbuf_new_auto();
 va_start(ap, fmt);
 sbuf_vprintf(sb, fmt, ap);
 va_end(ap);
 sbuf_finish(sb);
 gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO);
 gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
 gp->class = mp;
 gp->rank = 1;
 LIST_INIT(&gp->consumer);
 LIST_INIT(&gp->provider);
 LIST_INSERT_HEAD(&mp->geom, gp, geom);
 TAILQ_INSERT_HEAD(&geoms, gp, geoms);
 strcpy(gp->name, sbuf_data(sb));
 sbuf_delete(sb);
 /* Fill in defaults from class */
 gp->start = mp->start;
 gp->spoiled = mp->spoiled;
 gp->attrchanged = mp->attrchanged;
 gp->providergone = mp->providergone;
 gp->dumpconf = mp->dumpconf;
 gp->access = mp->access;
 gp->orphan = mp->orphan;
 gp->ioctl = mp->ioctl;
 gp->resize = mp->resize;
 return (gp);
}

 void
 g_destroy_geom(struct g_geom *gp)
{

 g_topology_assert();
 G_VALID_GEOM(gp);
 g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name);
 KASSERT(LIST_EMPTY(&gp->consumer),
 ("g_destroy_geom(%s) with consumer(s) [%p]",
 gp->name, LIST_FIRST(&gp->consumer)));
 KASSERT(LIST_EMPTY(&gp->provider),
 ("g_destroy_geom(%s) with provider(s) [%p]",
 gp->name, LIST_FIRST(&gp->provider)));
 g_cancel_event(gp);
 LIST_REMOVE(gp, geom);
 TAILQ_REMOVE(&geoms, gp, geoms);
 g_free(gp->name);
 g_free(gp);
}

 /*
 * This function is called (repeatedly) until the geom has withered away.
 */
 void
 g_wither_geom(struct g_geom *gp, int error)
{
 struct g_provider *pp;

 g_topology_assert();
 G_VALID_GEOM(gp);
 g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name);
 if (!(gp->flags & G_GEOM_WITHER)) {
 gp->flags |= G_GEOM_WITHER;
 LIST_FOREACH(pp, &gp->provider, provider)
 if (!(pp->flags & G_PF_ORPHAN))
 g_orphan_provider(pp, error);
 }
 g_do_wither();
}

 /*
 * Convenience function to destroy a particular provider.
 */
 void
 g_wither_provider(struct g_provider *pp, int error)
{

 pp->flags |= G_PF_WITHER;
 if (!(pp->flags & G_PF_ORPHAN))
 g_orphan_provider(pp, error);
}

 /*
 * This function is called (repeatedly) until the has withered away.
 */
 void
 g_wither_geom_close(struct g_geom *gp, int error)
{
 struct g_consumer *cp;

 g_topology_assert();
 G_VALID_GEOM(gp);
 g_trace(G_T_TOPOLOGY, "g_wither_geom_close(%p(%s))", gp, gp->name);
 LIST_FOREACH(cp, &gp->consumer, consumer)
 if (cp->acr || cp->acw || cp->ace)
 g_access(cp, -cp->acr, -cp->acw, -cp->ace);
 g_wither_geom(gp, error);
}

 /*
 * This function is called (repeatedly) until we cant wash away more
 * withered bits at present.
 */
 void
 g_wither_washer()
{
 struct g_class *mp;
 struct g_geom *gp, *gp2;
 struct g_provider *pp, *pp2;
 struct g_consumer *cp, *cp2;

 g_topology_assert();
 LIST_FOREACH(mp, &g_classes, class) {
 LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
 LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
 if (!(pp->flags & G_PF_WITHER))
 continue;
 if (LIST_EMPTY(&pp->consumers))
 g_destroy_provider(pp);
 }
 if (!(gp->flags & G_GEOM_WITHER))
 continue;
 LIST_FOREACH_SAFE(pp, &gp->provider, provider, pp2) {
 if (LIST_EMPTY(&pp->consumers))
 g_destroy_provider(pp);
 }
 LIST_FOREACH_SAFE(cp, &gp->consumer, consumer, cp2) {
 if (cp->acr || cp->acw || cp->ace)
 continue;
 if (cp->provider != NULL)
 g_detach(cp);
 g_destroy_consumer(cp);
 }
 if (LIST_EMPTY(&gp->provider) &&
 LIST_EMPTY(&gp->consumer))
 g_destroy_geom(gp);
 }
 }
}

 struct g_consumer *
 g_new_consumer(struct g_geom *gp)
{
 struct g_consumer *cp;

 g_topology_assert();
 G_VALID_GEOM(gp);
 KASSERT(!(gp->flags & G_GEOM_WITHER),
 ("g_new_consumer on WITHERing geom(%s) (class %s)",
 gp->name, gp->class->name));
 KASSERT(gp->orphan != NULL,
 ("g_new_consumer on geom(%s) (class %s) without orphan",
 gp->name, gp->class->name));

 cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO);
 cp->geom = gp;
 cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED,
 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
 LIST_INSERT_HEAD(&gp->consumer, cp, consumer);
 return(cp);
}

 void
 g_destroy_consumer(struct g_consumer *cp)
{
 struct g_geom *gp;

 g_topology_assert();
 G_VALID_CONSUMER(cp);
 g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp);
 KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached"));
 KASSERT (cp->acr == 0, ("g_destroy_consumer with acr"));
 KASSERT (cp->acw == 0, ("g_destroy_consumer with acw"));
 KASSERT (cp->ace == 0, ("g_destroy_consumer with ace"));
 g_cancel_event(cp);
 gp = cp->geom;
 LIST_REMOVE(cp, consumer);
 devstat_remove_entry(cp->stat);
 g_free(cp);
 if (gp->flags & G_GEOM_WITHER)
 g_do_wither();
}

 static void
 g_new_provider_event(void *arg, int flag)
{
 struct g_class *mp;
 struct g_provider *pp;
 struct g_consumer *cp, *next_cp;

 g_topology_assert();
 if (flag == EV_CANCEL)
 return;
 if (g_shutdown)
 return;
 pp = arg;
 G_VALID_PROVIDER(pp);
 KASSERT(!(pp->flags & G_PF_WITHER),
 ("g_new_provider_event but withered"));
 LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, next_cp) {
 if ((cp->flags & G_CF_ORPHAN) == 0 &&
 cp->geom->attrchanged != NULL)
 cp->geom->attrchanged(cp, "GEOM::media");
 }
 if (g_notaste)
 return;
 LIST_FOREACH(mp, &g_classes, class) {
 if (mp->taste == NULL)
 continue;
 LIST_FOREACH(cp, &pp->consumers, consumers)
 if (cp->geom->class == mp &&
 (cp->flags & G_CF_ORPHAN) == 0)
 break;
 if (cp != NULL)
 continue;
 mp->taste(mp, pp, 0);
 g_topology_assert();
 }
}

 struct g_provider *
 g_new_providerf(struct g_geom *gp, const char *fmt, ...)
{
 struct g_provider *pp;
 struct sbuf *sb;
 va_list ap;

 g_topology_assert();
 G_VALID_GEOM(gp);
 KASSERT(gp->access != NULL,
 ("new provider on geom(%s) without ->access (class %s)",
 gp->name, gp->class->name));
 KASSERT(gp->start != NULL,
 ("new provider on geom(%s) without ->start (class %s)",
 gp->name, gp->class->name));
 KASSERT(!(gp->flags & G_GEOM_WITHER),
 ("new provider on WITHERing geom(%s) (class %s)",
 gp->name, gp->class->name));
 sb = sbuf_new_auto();
 va_start(ap, fmt);
 sbuf_vprintf(sb, fmt, ap);
 va_end(ap);
 sbuf_finish(sb);
 pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
 pp->name = (char *)(pp + 1);
 strcpy(pp->name, sbuf_data(sb));
 sbuf_delete(sb);
 LIST_INIT(&pp->consumers);
 LIST_INIT(&pp->aliases);
 pp->error = ENXIO;
 pp->geom = gp;
 pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED,
 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
 LIST_INSERT_HEAD(&gp->provider, pp, provider);
 g_post_event(g_new_provider_event, pp, M_WAITOK, pp, gp, NULL);
 return (pp);
}

 void
 g_provider_add_alias(struct g_provider *pp, const char *fmt, ...)
{
 struct sbuf *sb;
 struct g_geom_alias *gap;
 va_list ap;

 /*
 * Generate the alias string and save it in the list.
 */
 sb = sbuf_new_auto();
 va_start(ap, fmt);
 sbuf_vprintf(sb, fmt, ap);
 va_end(ap);
 sbuf_finish(sb);

 LIST_FOREACH(gap, &pp->aliases, ga_next) {
 if (strcmp(gap->ga_alias, sbuf_data(sb)) != 0)
 continue;
 /* Don't re-add the same alias. */
 sbuf_delete(sb);
 return;
 }

 gap = g_malloc(sizeof(*gap) + sbuf_len(sb) + 1, M_WAITOK | M_ZERO);
 memcpy((char *)(gap + 1), sbuf_data(sb), sbuf_len(sb));
 sbuf_delete(sb);
 gap->ga_alias = (const char *)(gap + 1);
 LIST_INSERT_HEAD(&pp->aliases, gap, ga_next);
}

 void
 g_error_provider(struct g_provider *pp, int error)
{

 /* G_VALID_PROVIDER(pp); We may not have g_topology */
 pp->error = error;
}

 static void
 g_resize_provider_event(void *arg, int flag)
{
 struct g_hh00 *hh;
 struct g_class *mp;
 struct g_geom *gp;
 struct g_provider *pp;
 struct g_consumer *cp, *cp2;
 off_t size;

 g_topology_assert();
 if (g_shutdown)
 return;

 hh = arg;
 pp = hh->pp;
 size = hh->size;
 g_free(hh);

 G_VALID_PROVIDER(pp);
 KASSERT(!(pp->flags & G_PF_WITHER),
 ("g_resize_provider_event but withered"));
 g_trace(G_T_TOPOLOGY, "g_resize_provider_event(%p)", pp);

 LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
 gp = cp->geom;
 if (gp->resize == NULL && size < pp->mediasize) {
 /*
 * XXX: g_dev_orphan method does deferred destroying
 * and it is possible, that other event could already
 * call the orphan method. Check consumer's flags to
 * do not schedule it twice.
 */
 if (cp->flags & G_CF_ORPHAN)
 continue;
 cp->flags |= G_CF_ORPHAN;
 cp->geom->orphan(cp);
 }
 }

 pp->mediasize = size;

 LIST_FOREACH_SAFE(cp, &pp->consumers, consumers, cp2) {
 gp = cp->geom;
 if ((gp->flags & G_GEOM_WITHER) == 0 && gp->resize != NULL)
 gp->resize(cp);
 }

 /*
 * After resizing, the previously invalid GEOM class metadata
 * might become valid. This means we should retaste.
 */
 LIST_FOREACH(mp, &g_classes, class) {
 if (mp->taste == NULL)
 continue;
 LIST_FOREACH(cp, &pp->consumers, consumers)
 if (cp->geom->class == mp &&
 (cp->flags & G_CF_ORPHAN) == 0)
 break;
 if (cp != NULL)
 continue;
 mp->taste(mp, pp, 0);
 g_topology_assert();
 }
}

 void
 g_resize_provider(struct g_provider *pp, off_t size)
{
 struct g_hh00 *hh;

 G_VALID_PROVIDER(pp);
 if (pp->flags & G_PF_WITHER)
 return;

 if (size == pp->mediasize)
 return;

 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO);
 hh->pp = pp;
 hh->size = size;
 g_post_event(g_resize_provider_event, hh, M_WAITOK, NULL);
}

 struct g_provider *
 g_provider_by_name(char const *arg)
{
 struct g_class *cp;
 struct g_geom *gp;
 struct g_provider *pp, *wpp;

 if (strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
 arg += sizeof(_PATH_DEV) - 1;

 wpp = NULL;
 LIST_FOREACH(cp, &g_classes, class) {
 LIST_FOREACH(gp, &cp->geom, geom) {
 LIST_FOREACH(pp, &gp->provider, provider) {
 if (strcmp(arg, pp->name) != 0)
 continue;
 if ((gp->flags & G_GEOM_WITHER) == 0 &&
 (pp->flags & G_PF_WITHER) == 0)
 return (pp);
 else
 wpp = pp;
 }
 }
 }

 return (wpp);
}

 void
 g_destroy_provider(struct g_provider *pp)
{
 struct g_geom *gp;
 struct g_geom_alias *gap, *gaptmp;

 g_topology_assert();
 G_VALID_PROVIDER(pp);
 KASSERT(LIST_EMPTY(&pp->consumers),
 ("g_destroy_provider but attached"));
 KASSERT (pp->acr == 0, ("g_destroy_provider with acr"));
 KASSERT (pp->acw == 0, ("g_destroy_provider with acw"));
 KASSERT (pp->ace == 0, ("g_destroy_provider with ace"));
 g_cancel_event(pp);
 LIST_REMOVE(pp, provider);
 gp = pp->geom;
 devstat_remove_entry(pp->stat);
 /*
 * If a callback was provided, send notification that the provider
 * is now gone.
 */
 if (gp->providergone != NULL)
 gp->providergone(pp);
 LIST_FOREACH_SAFE(gap, &pp->aliases, ga_next, gaptmp)
 g_free(gap);
 g_free(pp);
 if ((gp->flags & G_GEOM_WITHER))
 g_do_wither();
}

 /*
 * We keep the "geoms" list sorted by topological order (== increasing
 * numerical rank) at all times.
 * When an attach is done, the attaching geoms rank is invalidated
 * and it is moved to the tail of the list.
 * All geoms later in the sequence has their ranks reevaluated in
 * sequence. If we cannot assign rank to a geom because it's
 * prerequisites do not have rank, we move that element to the tail
 * of the sequence with invalid rank as well.
 * At some point we encounter our original geom and if we stil fail
 * to assign it a rank, there must be a loop and we fail back to
 * g_attach() which detach again and calls redo_rank again
 * to fix up the damage.
 * It would be much simpler code wise to do it recursively, but we
 * can't risk that on the kernel stack.
 */

 static int
 redo_rank(struct g_geom *gp)
{
 struct g_consumer *cp;
 struct g_geom *gp1, *gp2;
 int n, m;

 g_topology_assert();
 G_VALID_GEOM(gp);

 /* Invalidate this geoms rank and move it to the tail */
 gp1 = TAILQ_NEXT(gp, geoms);
 if (gp1 != NULL) {
 gp->rank = 0;
 TAILQ_REMOVE(&geoms, gp, geoms);
 TAILQ_INSERT_TAIL(&geoms, gp, geoms);
 } else {
 gp1 = gp;
 }

 /* re-rank the rest of the sequence */
 for (; gp1 != NULL; gp1 = gp2) {
 gp1->rank = 0;
 m = 1;
 LIST_FOREACH(cp, &gp1->consumer, consumer) {
 if (cp->provider == NULL)
 continue;
 n = cp->provider->geom->rank;
 if (n == 0) {
 m = 0;
 break;
 } else if (n >= m)
 m = n + 1;
 }
 gp1->rank = m;
 gp2 = TAILQ_NEXT(gp1, geoms);

 /* got a rank, moving on */
 if (m != 0)
 continue;

 /* no rank to original geom means loop */
 if (gp == gp1)
 return (ELOOP);

 /* no rank, put it at the end move on */
 TAILQ_REMOVE(&geoms, gp1, geoms);
 TAILQ_INSERT_TAIL(&geoms, gp1, geoms);
 }
 return (0);
}

 int
 g_attach(struct g_consumer *cp, struct g_provider *pp)
{
 int error;

 g_topology_assert();
 G_VALID_CONSUMER(cp);
 G_VALID_PROVIDER(pp);
 g_trace(G_T_TOPOLOGY, "g_attach(%p, %p)", cp, pp);
 KASSERT(cp->provider == NULL, ("attach but attached"));
 if ((pp->flags & (G_PF_ORPHAN | G_PF_WITHER)) != 0)
 return (ENXIO);
 cp->provider = pp;
 cp->flags &= ~G_CF_ORPHAN;
 LIST_INSERT_HEAD(&pp->consumers, cp, consumers);
 error = redo_rank(cp->geom);
 if (error) {
 LIST_REMOVE(cp, consumers);
 cp->provider = NULL;
 redo_rank(cp->geom);
 }
 return (error);
}

 void
 g_detach(struct g_consumer *cp)
{
 struct g_provider *pp;

 g_topology_assert();
 G_VALID_CONSUMER(cp);
 g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp);
 KASSERT(cp->provider != NULL, ("detach but not attached"));
 KASSERT(cp->acr == 0, ("detach but nonzero acr"));
 KASSERT(cp->acw == 0, ("detach but nonzero acw"));
 KASSERT(cp->ace == 0, ("detach but nonzero ace"));
 KASSERT(cp->nstart == cp->nend,
 ("detach with active requests"));
 pp = cp->provider;
 LIST_REMOVE(cp, consumers);
 cp->provider = NULL;
 if ((cp->geom->flags & G_GEOM_WITHER) ||
 (pp->geom->flags & G_GEOM_WITHER) ||
 (pp->flags & G_PF_WITHER))
 g_do_wither();
 redo_rank(cp->geom);
}

 /*
 * g_access()
 *
 * Access-check with delta values. The question asked is "can provider
 * "cp" change the access counters by the relative amounts dc[rwe] ?"
 */

 int
 g_access(struct g_consumer *cp, int dcr, int dcw, int dce)
{
 struct g_provider *pp;
 struct g_geom *gp;
 int pw, pe;
#ifdef INVARIANTS
 int sr, sw, se;
#endif
 int error;

 g_topology_assert();
 G_VALID_CONSUMER(cp);
 pp = cp->provider;
 KASSERT(pp != NULL, ("access but not attached"));
 G_VALID_PROVIDER(pp);
 gp = pp->geom;

 g_trace(G_T_ACCESS, "g_access(%p(%s), %d, %d, %d)",
 cp, pp->name, dcr, dcw, dce);

 KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr"));
 KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw"));
 KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace"));
 KASSERT(dcr != 0 || dcw != 0 || dce != 0, ("NOP access request"));
 KASSERT(cp->acr + dcr != 0 || cp->acw + dcw != 0 ||
 cp->ace + dce != 0 || cp->nstart == cp->nend,
 ("Last close with active requests"));
 KASSERT(gp->access != NULL, ("NULL geom->access"));

 /*
 * If our class cares about being spoiled, and we have been, we
 * are probably just ahead of the event telling us that. Fail
 * now rather than having to unravel this later.
 */
 if (cp->geom->spoiled != NULL && (cp->flags & G_CF_SPOILED) &&
 (dcr > 0 || dcw > 0 || dce > 0))
 return (ENXIO);

 /*
 * A number of GEOM classes either need to perform an I/O on the first
 * open or to acquire a different subsystem's lock. To do that they
 * may have to drop the topology lock.
 * Other GEOM classes perform special actions when opening a lower rank
 * geom for the first time. As a result, more than one thread may
 * end up performing the special actions.
 * So, we prevent concurrent "first" opens by marking the consumer with
 * special flag.
 *
 * Note that if the geom's access method never drops the topology lock,
 * then we will never see G_GEOM_IN_ACCESS here.
 */
 while ((gp->flags & G_GEOM_IN_ACCESS) != 0) {
 g_trace(G_T_ACCESS,
 "%s: race on geom %s via provider %s and consumer of %s",
 __func__, gp->name, pp->name, cp->geom->name);
 gp->flags |= G_GEOM_ACCESS_WAIT;
 g_topology_sleep(gp, 0);
 }

 /*
 * Figure out what counts the provider would have had, if this
 * consumer had (r0w0e0) at this time.
 */
 pw = pp->acw - cp->acw;
 pe = pp->ace - cp->ace;

 g_trace(G_T_ACCESS,
 "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)",
 dcr, dcw, dce,
 cp->acr, cp->acw, cp->ace,
 pp->acr, pp->acw, pp->ace,
 pp, pp->name);

 /* If foot-shooting is enabled, any open on rank#1 is OK */
 if ((g_debugflags & G_F_FOOTSHOOTING) && gp->rank == 1)
 ;
 /* If we try exclusive but already write: fail */
 else if (dce > 0 && pw > 0)
 return (EPERM);
 /* If we try write but already exclusive: fail */
 else if (dcw > 0 && pe > 0)
 return (EPERM);
 /* If we try to open more but provider is error'ed: fail */
 else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0) {
 printf("%s(%d): provider %s has error %d set\n",
 __func__, __LINE__, pp->name, pp->error);
 return (pp->error);
 }

 /* Ok then... */

#ifdef INVARIANTS
 sr = cp->acr;
 sw = cp->acw;
 se = cp->ace;
#endif
 gp->flags |= G_GEOM_IN_ACCESS;
 error = gp->access(pp, dcr, dcw, dce);
 KASSERT(dcr > 0 || dcw > 0 || dce > 0 || error == 0,
 ("Geom provider %s::%s dcr=%d dcw=%d dce=%d error=%d failed "
 "closing ->access()", gp->class->name, pp->name, dcr, dcw,
 dce, error));

 g_topology_assert();
 gp->flags &= ~G_GEOM_IN_ACCESS;
 KASSERT(cp->acr == sr && cp->acw == sw && cp->ace == se,
 ("Access counts changed during geom->access"));
 if ((gp->flags & G_GEOM_ACCESS_WAIT) != 0) {
 gp->flags &= ~G_GEOM_ACCESS_WAIT;
 wakeup(gp);
 }

 if (!error) {
 /*
 * If we open first write, spoil any partner consumers.
 * If we close last write and provider is not errored,
 * trigger re-taste.
 */
 if (pp->acw == 0 && dcw != 0)
 g_spoil(pp, cp);
 else if (pp->acw != 0 && pp->acw == -dcw && pp->error == 0 &&
 !(gp->flags & G_GEOM_WITHER))
 g_post_event(g_new_provider_event, pp, M_WAITOK,
 pp, NULL);

 pp->acr += dcr;
 pp->acw += dcw;
 pp->ace += dce;
 cp->acr += dcr;
 cp->acw += dcw;
 cp->ace += dce;
 if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)
 KASSERT(pp->sectorsize > 0,
 ("Provider %s lacks sectorsize", pp->name));
 if ((cp->geom->flags & G_GEOM_WITHER) &&
 cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
 g_do_wither();
 }
 return (error);
}

 int
 g_handleattr_int(struct bio *bp, const char *attribute, int val)
{

 return (g_handleattr(bp, attribute, &val, sizeof val));
}

 int
 g_handleattr_uint16_t(struct bio *bp, const char *attribute, uint16_t val)
{

 return (g_handleattr(bp, attribute, &val, sizeof val));
}

 int
 g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val)
{

 return (g_handleattr(bp, attribute, &val, sizeof val));
}

 int
 g_handleattr_str(struct bio *bp, const char *attribute, const char *str)
{

 return (g_handleattr(bp, attribute, str, 0));
}

 int
 g_handleattr(struct bio *bp, const char *attribute, const void *val, int len)
{
 int error = 0;

 if (strcmp(bp->bio_attribute, attribute))
 return (0);
 if (len == 0) {
 bzero(bp->bio_data, bp->bio_length);
 if (strlcpy(bp->bio_data, val, bp->bio_length) >=
 bp->bio_length) {
 printf("%s: %s %s bio_length %jd strlen %zu -> EFAULT\n",
 __func__, bp->bio_to->name, attribute,
 (intmax_t)bp->bio_length, strlen(val));
 error = EFAULT;
 }
 } else if (bp->bio_length == len) {
 bcopy(val, bp->bio_data, len);
 } else {
 printf("%s: %s %s bio_length %jd len %d -> EFAULT\n", __func__,
 bp->bio_to->name, attribute, (intmax_t)bp->bio_length, len);
 error = EFAULT;
 }
 if (error == 0)
 bp->bio_completed = bp->bio_length;
 g_io_deliver(bp, error);
 return (1);
}

 int
 g_std_access(struct g_provider *pp,
 int dr __unused, int dw __unused, int de __unused)
{

 g_topology_assert();
 G_VALID_PROVIDER(pp);
 return (0);
}

 void
 g_std_done(struct bio *bp)
{
 struct bio *bp2;

 bp2 = bp->bio_parent;
 if (bp2->bio_error == 0)
 bp2->bio_error = bp->bio_error;
 bp2->bio_completed += bp->bio_completed;
 g_destroy_bio(bp);
 bp2->bio_inbed++;
 if (bp2->bio_children == bp2->bio_inbed) {
 if (bp2->bio_cmd == BIO_SPEEDUP)
 bp2->bio_completed = bp2->bio_length;
 g_io_deliver(bp2, bp2->bio_error);
 }
}

 /* XXX: maybe this is only g_slice_spoiled */

 void
 g_std_spoiled(struct g_consumer *cp)
{
 struct g_geom *gp;
 struct g_provider *pp;

 g_topology_assert();
 G_VALID_CONSUMER(cp);
 g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp);
 cp->flags |= G_CF_ORPHAN;
 g_detach(cp);
 gp = cp->geom;
 LIST_FOREACH(pp, &gp->provider, provider)
 g_orphan_provider(pp, ENXIO);
 g_destroy_consumer(cp);
 if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer))
 g_destroy_geom(gp);
 else
 gp->flags |= G_GEOM_WITHER;
}

 /*
 * Spoiling happens when a provider is opened for writing, but consumers
 * which are configured by in-band data are attached (slicers for instance).
 * Since the write might potentially change the in-band data, such consumers
 * need to re-evaluate their existence after the writing session closes.
 * We do this by (offering to) tear them down when the open for write happens
 * in return for a re-taste when it closes again.
 * Together with the fact that such consumers grab an 'e' bit whenever they
 * are open, regardless of mode, this ends up DTRT.
 */

 static void
 g_spoil_event(void *arg, int flag)
{
 struct g_provider *pp;
 struct g_consumer *cp, *cp2;

 g_topology_assert();
 if (flag == EV_CANCEL)
 return;
 pp = arg;
 G_VALID_PROVIDER(pp);
 g_trace(G_T_TOPOLOGY, "%s %p(%s:%s:%s)", __func__, pp,
 pp->geom->class->name, pp->geom->name, pp->name);
 for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) {
 cp2 = LIST_NEXT(cp, consumers);
 if ((cp->flags & G_CF_SPOILED) == 0)
 continue;
 cp->flags &= ~G_CF_SPOILED;
 if (cp->geom->spoiled == NULL)
 continue;
 cp->geom->spoiled(cp);
 g_topology_assert();
 }
}

 void
 g_spoil(struct g_provider *pp, struct g_consumer *cp)
{
 struct g_consumer *cp2;

 g_topology_assert();
 G_VALID_PROVIDER(pp);
 G_VALID_CONSUMER(cp);

 LIST_FOREACH(cp2, &pp->consumers, consumers) {
 if (cp2 == cp)
 continue;
 /*
 KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr));
 KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw));
*/
 KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace));
 cp2->flags |= G_CF_SPOILED;
 }
 g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL);
}

 static void
 g_media_changed_event(void *arg, int flag)
{
 struct g_provider *pp;
 int retaste;

 g_topology_assert();
 if (flag == EV_CANCEL)
 return;
 pp = arg;
 G_VALID_PROVIDER(pp);

 /*
 * If provider was not open for writing, queue retaste after spoiling.
 * If it was, retaste will happen automatically on close.
 */
 retaste = (pp->acw == 0 && pp->error == 0 &&
 !(pp->geom->flags & G_GEOM_WITHER));
 g_spoil_event(arg, flag);
 if (retaste)
 g_post_event(g_new_provider_event, pp, M_WAITOK, pp, NULL);
}

 int
 g_media_changed(struct g_provider *pp, int flag)
{
 struct g_consumer *cp;

 LIST_FOREACH(cp, &pp->consumers, consumers)
 cp->flags |= G_CF_SPOILED;
 return (g_post_event(g_media_changed_event, pp, flag, pp, NULL));
}

 int
 g_media_gone(struct g_provider *pp, int flag)
{
 struct g_consumer *cp;

 LIST_FOREACH(cp, &pp->consumers, consumers)
 cp->flags |= G_CF_SPOILED;
 return (g_post_event(g_spoil_event, pp, flag, pp, NULL));
}

 int
 g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len)
{
 int error, i;

 i = len;
 error = g_io_getattr(attr, cp, &i, var);
 if (error)
 return (error);
 if (i != len)
 return (EINVAL);
 return (0);
}

 static int
 g_get_device_prefix_len(const char *name)
{
 int len;

 if (strncmp(name, "ada", 3) == 0)
 len = 3;
 else if (strncmp(name, "ad", 2) == 0)
 len = 2;
 else
 return (0);
 if (name[len] < '0' || name[len] > '9')
 return (0);
 do {
 len++;
 } while (name[len] >= '0' && name[len] <= '9');
 return (len);
}

 int
 g_compare_names(const char *namea, const char *nameb)
{
 int deva, devb;

 if (strcmp(namea, nameb) == 0)
 return (1);
 deva = g_get_device_prefix_len(namea);
 if (deva == 0)
 return (0);
 devb = g_get_device_prefix_len(nameb);
 if (devb == 0)
 return (0);
 if (strcmp(namea + deva, nameb + devb) == 0)
 return (1);
 return (0);
}

#if defined(DIAGNOSTIC) || defined(DDB)
 /*
 * This function walks the mesh and returns a non-zero integer if it
 * finds the argument pointer is an object. The return value indicates
 * which type of object it is believed to be. If topology is not locked,
 * this function is potentially dangerous, but we don't assert that the
 * topology lock is held when called from debugger.
 */
 int
 g_valid_obj(void const *ptr)
{
 struct g_class *mp;
 struct g_geom *gp;
 struct g_consumer *cp;
 struct g_provider *pp;

#ifdef KDB
 if (kdb_active == 0)
#endif
 g_topology_assert();

 LIST_FOREACH(mp, &g_classes, class) {
 if (ptr == mp)
 return (1);
 LIST_FOREACH(gp, &mp->geom, geom) {
 if (ptr == gp)
 return (2);
 LIST_FOREACH(cp, &gp->consumer, consumer)
 if (ptr == cp)
 return (3);
 LIST_FOREACH(pp, &gp->provider, provider)
 if (ptr == pp)
 return (4);
 }
 }
 return(0);
}
#endif

#ifdef DDB

#define gprintf(...) do { \
 db_printf("%*s", indent, ""); \
 db_printf(__VA_ARGS__); \
} while (0)
#define gprintln(...) do { \
 gprintf(__VA_ARGS__); \
 db_printf("\n"); \
} while (0)

#define ADDFLAG(obj, flag, sflag) do { \
 if ((obj)->flags & (flag)) { \
 if (comma) \
 strlcat(str, ",", size); \
 strlcat(str, (sflag), size); \
 comma = 1; \
 } \
} while (0)

 static char *
 provider_flags_to_string(struct g_provider *pp, char *str, size_t size)
{
 int comma = 0;

 bzero(str, size);
 if (pp->flags == 0) {
 strlcpy(str, "NONE", size);
 return (str);
 }
 ADDFLAG(pp, G_PF_WITHER, "G_PF_WITHER");
 ADDFLAG(pp, G_PF_ORPHAN, "G_PF_ORPHAN");
 return (str);
}

 static char *
 geom_flags_to_string(struct g_geom *gp, char *str, size_t size)
{
 int comma = 0;

 bzero(str, size);
 if (gp->flags == 0) {
 strlcpy(str, "NONE", size);
 return (str);
 }
 ADDFLAG(gp, G_GEOM_WITHER, "G_GEOM_WITHER");
 return (str);
}
 static void
 db_show_geom_consumer(int indent, struct g_consumer *cp)
{

 if (indent == 0) {
 gprintln("consumer: %p", cp);
 gprintln(" class: %s (%p)", cp->geom->class->name,
 cp->geom->class);
 gprintln(" geom: %s (%p)", cp->geom->name, cp->geom);
 if (cp->provider == NULL)
 gprintln(" provider: none");
 else {
 gprintln(" provider: %s (%p)", cp->provider->name,
 cp->provider);
 }
 gprintln(" access: r%dw%de%d", cp->acr, cp->acw, cp->ace);
 gprintln(" flags: 0x%04x", cp->flags);
#ifdef INVARIANTS
 gprintln(" nstart: %u", cp->nstart);
 gprintln(" nend: %u", cp->nend);
#endif
 } else {
 gprintf("consumer: %p (%s), access=r%dw%de%d", cp,
 cp->provider != NULL ? cp->provider->name : "none",
 cp->acr, cp->acw, cp->ace);
 if (cp->flags)
 db_printf(", flags=0x%04x", cp->flags);
 db_printf("\n");
 }
}

 static void
 db_show_geom_provider(int indent, struct g_provider *pp)
{
 struct g_consumer *cp;
 char flags[64];

 if (indent == 0) {
 gprintln("provider: %s (%p)", pp->name, pp);
 gprintln(" class: %s (%p)", pp->geom->class->name,
 pp->geom->class);
 gprintln(" geom: %s (%p)", pp->geom->name, pp->geom);
 gprintln(" mediasize: %jd", (intmax_t)pp->mediasize);
 gprintln(" sectorsize: %u", pp->sectorsize);
 gprintln(" stripesize: %ju", (uintmax_t)pp->stripesize);
 gprintln(" stripeoffset: %ju", (uintmax_t)pp->stripeoffset);
 gprintln(" access: r%dw%de%d", pp->acr, pp->acw,
 pp->ace);
 gprintln(" flags: %s (0x%04x)",
 provider_flags_to_string(pp, flags, sizeof(flags)),
 pp->flags);
 gprintln(" error: %d", pp->error);
 if (LIST_EMPTY(&pp->consumers))
 gprintln(" consumers: none");
 } else {
 gprintf("provider: %s (%p), access=r%dw%de%d",
 pp->name, pp, pp->acr, pp->acw, pp->ace);
 if (pp->flags != 0) {
 db_printf(", flags=%s (0x%04x)",
 provider_flags_to_string(pp, flags, sizeof(flags)),
 pp->flags);
 }
 db_printf("\n");
 }
 if (!LIST_EMPTY(&pp->consumers)) {
 LIST_FOREACH(cp, &pp->consumers, consumers) {
 db_show_geom_consumer(indent + 2, cp);
 if (db_pager_quit)
 break;
 }
 }
}

 static void
 db_show_geom_geom(int indent, struct g_geom *gp)
{
 struct g_provider *pp;
 struct g_consumer *cp;
 char flags[64];

 if (indent == 0) {
 gprintln("geom: %s (%p)", gp->name, gp);
 gprintln(" class: %s (%p)", gp->class->name, gp->class);
 gprintln(" flags: %s (0x%04x)",
 geom_flags_to_string(gp, flags, sizeof(flags)), gp->flags);
 gprintln(" rank: %d", gp->rank);
 if (LIST_EMPTY(&gp->provider))
 gprintln(" providers: none");
 if (LIST_EMPTY(&gp->consumer))
 gprintln(" consumers: none");
 } else {
 gprintf("geom: %s (%p), rank=%d", gp->name, gp, gp->rank);
 if (gp->flags != 0) {
 db_printf(", flags=%s (0x%04x)",
 geom_flags_to_string(gp, flags, sizeof(flags)),
 gp->flags);
 }
 db_printf("\n");
 }
 if (!LIST_EMPTY(&gp->provider)) {
 LIST_FOREACH(pp, &gp->provider, provider) {
 db_show_geom_provider(indent + 2, pp);
 if (db_pager_quit)
 break;
 }
 }
 if (!LIST_EMPTY(&gp->consumer)) {
 LIST_FOREACH(cp, &gp->consumer, consumer) {
 db_show_geom_consumer(indent + 2, cp);
 if (db_pager_quit)
 break;
 }
 }
}

 static void
 db_show_geom_class(struct g_class *mp)
{
 struct g_geom *gp;

 db_printf("class: %s (%p)\n", mp->name, mp);
 LIST_FOREACH(gp, &mp->geom, geom) {
 db_show_geom_geom(2, gp);
 if (db_pager_quit)
 break;
 }
}

 /*
 * Print the GEOM topology or the given object.
 */
 DB_SHOW_COMMAND(geom, db_show_geom)
{
 struct g_class *mp;

 if (!have_addr) {
 /* No address given, print the entire topology. */
 LIST_FOREACH(mp, &g_classes, class) {
 db_show_geom_class(mp);
 db_printf("\n");
 if (db_pager_quit)
 break;
 }
 } else {
 switch (g_valid_obj((void *)addr)) {
 case 1:
 db_show_geom_class((struct g_class *)addr);
 break;
 case 2:
 db_show_geom_geom(0, (struct g_geom *)addr);
 break;
 case 3:
 db_show_geom_consumer(0, (struct g_consumer *)addr);
 break;
 case 4:
 db_show_geom_provider(0, (struct g_provider *)addr);
 break;
 default:
 db_printf("Not a GEOM object.\n");
 break;
 }
 }
}

 static void
 db_print_bio_cmd(struct bio *bp)
{
 db_printf(" cmd: ");
 switch (bp->bio_cmd) {
 case BIO_READ: db_printf("BIO_READ"); break;
 case BIO_WRITE: db_printf("BIO_WRITE"); break;
 case BIO_DELETE: db_printf("BIO_DELETE"); break;
 case BIO_GETATTR: db_printf("BIO_GETATTR"); break;
 case BIO_FLUSH: db_printf("BIO_FLUSH"); break;
 case BIO_CMD0: db_printf("BIO_CMD0"); break;
 case BIO_CMD1: db_printf("BIO_CMD1"); break;
 case BIO_CMD2: db_printf("BIO_CMD2"); break;
 case BIO_ZONE: db_printf("BIO_ZONE"); break;
 default: db_printf("UNKNOWN"); break;
 }
 db_printf("\n");
}

 static void
 db_print_bio_flags(struct bio *bp)
{
 int comma;

 comma = 0;
 db_printf(" flags: ");
 if (bp->bio_flags & BIO_ERROR) {
 db_printf("BIO_ERROR");
 comma = 1;
 }
 if (bp->bio_flags & BIO_DONE) {
 db_printf("%sBIO_DONE", (comma ? ", " : ""));
 comma = 1;
 }
 if (bp->bio_flags & BIO_ONQUEUE)
 db_printf("%sBIO_ONQUEUE", (comma ? ", " : ""));
 db_printf("\n");
}

 /*
 * Print useful information in a BIO
 */
 DB_SHOW_COMMAND(bio, db_show_bio)
{
 struct bio *bp;

 if (have_addr) {
 bp = (struct bio *)addr;
 db_printf("BIO %p\n", bp);
 db_print_bio_cmd(bp);
 db_print_bio_flags(bp);
 db_printf(" cflags: 0x%hx\n", bp->bio_cflags);
 db_printf(" pflags: 0x%hx\n", bp->bio_pflags);
 db_printf(" offset: %jd\n", (intmax_t)bp->bio_offset);
 db_printf(" length: %jd\n", (intmax_t)bp->bio_length);
 db_printf(" bcount: %ld\n", bp->bio_bcount);
 db_printf(" resid: %ld\n", bp->bio_resid);
 db_printf(" completed: %jd\n", (intmax_t)bp->bio_completed);
 db_printf(" children: %u\n", bp->bio_children);
 db_printf(" inbed: %u\n", bp->bio_inbed);
 db_printf(" error: %d\n", bp->bio_error);
 db_printf(" parent: %p\n", bp->bio_parent);
 db_printf(" driver1: %p\n", bp->bio_driver1);
 db_printf(" driver2: %p\n", bp->bio_driver2);
 db_printf(" caller1: %p\n", bp->bio_caller1);
 db_printf(" caller2: %p\n", bp->bio_caller2);
 db_printf(" bio_from: %p\n", bp->bio_from);
 db_printf(" bio_to: %p\n", bp->bio_to);

#if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
 db_printf(" bio_track_bp: %p\n", bp->bio_track_bp);
#endif
 }
}

#undef gprintf
#undef gprintln
#undef ADDFLAG

#endif /* DDB */
 

Indexes created Wed Nov 12 03:56:33 PST 2025