geom_event.c revision 104053
192108Sphk/*- 292108Sphk * Copyright (c) 2002 Poul-Henning Kamp 392108Sphk * Copyright (c) 2002 Networks Associates Technology, Inc. 492108Sphk * All rights reserved. 592108Sphk * 692108Sphk * This software was developed for the FreeBSD Project by Poul-Henning Kamp 792108Sphk * and NAI Labs, the Security Research Division of Network Associates, Inc. 892108Sphk * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 992108Sphk * DARPA CHATS research program. 1092108Sphk * 1192108Sphk * Redistribution and use in source and binary forms, with or without 1292108Sphk * modification, are permitted provided that the following conditions 1392108Sphk * are met: 1492108Sphk * 1. Redistributions of source code must retain the above copyright 1592108Sphk * notice, this list of conditions and the following disclaimer. 1692108Sphk * 2. Redistributions in binary form must reproduce the above copyright 1792108Sphk * notice, this list of conditions and the following disclaimer in the 1892108Sphk * documentation and/or other materials provided with the distribution. 1992108Sphk * 3. The names of the authors may not be used to endorse or promote 2092108Sphk * products derived from this software without specific prior written 2192108Sphk * permission. 2292108Sphk * 2392108Sphk * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 2492108Sphk * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2592108Sphk * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2692108Sphk * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 2792108Sphk * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2892108Sphk * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2992108Sphk * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 3092108Sphk * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3192108Sphk * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3292108Sphk * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3392108Sphk * SUCH DAMAGE. 3492108Sphk * 3592108Sphk * $FreeBSD: head/sys/geom/geom_event.c 104053 2002-09-27 20:18:16Z phk $ 3692108Sphk */ 3792108Sphk 3892108Sphk/* 3992108Sphk * XXX: How do we in general know that objects referenced in events 4092108Sphk * have not been destroyed before we get around to handle the event ? 4192108Sphk */ 4292108Sphk 4392108Sphk#include <sys/param.h> 4492108Sphk#ifndef _KERNEL 4592108Sphk#include <stdio.h> 4692108Sphk#include <unistd.h> 4792108Sphk#include <string.h> 4892108Sphk#include <stdlib.h> 4992108Sphk#include <signal.h> 5092108Sphk#include <err.h> 5192108Sphk#else 5292108Sphk#include <sys/malloc.h> 5392108Sphk#include <sys/systm.h> 5492108Sphk#include <sys/kernel.h> 5592108Sphk#include <sys/lock.h> 5692108Sphk#include <sys/mutex.h> 5792108Sphk#endif 5892108Sphk#include <sys/errno.h> 5992108Sphk#include <sys/time.h> 6092108Sphk#include <geom/geom.h> 6193250Sphk#include <geom/geom_int.h> 6292108Sphk 6392108Sphkstatic struct event_tailq_head g_events = TAILQ_HEAD_INITIALIZER(g_events); 6492108Sphkstatic u_int g_pending_events, g_silence_events; 6593250Sphkstatic void g_do_event(struct g_event *ep); 6692108Sphkstatic TAILQ_HEAD(,g_provider) g_doorstep = TAILQ_HEAD_INITIALIZER(g_doorstep); 67104053Sphkstatic struct mtx g_eventlock; 6892108Sphk 6992108Sphkvoid 7092108Sphkg_silence(void) 7192108Sphk{ 7292108Sphk 7392108Sphk g_silence_events = 1; 7492108Sphk} 7592108Sphk 7692108Sphkvoid 7798066Sphkg_waitidle(void) 7892108Sphk{ 7992108Sphk 8092108Sphk g_silence_events = 0; 8192108Sphk mtx_lock(&Giant); 8292108Sphk wakeup(&g_silence_events); 8392108Sphk while (g_pending_events) 8498066Sphk tsleep(&g_pending_events, PPAUSE, "g_waitidle", hz/5); 8592108Sphk mtx_unlock(&Giant); 8692108Sphk} 8792108Sphk 8892108Sphkvoid 8992108Sphkg_orphan_provider(struct g_provider *pp, int error) 9092108Sphk{ 9192108Sphk 9292108Sphk g_trace(G_T_TOPOLOGY, "g_orphan_provider(%p(%s), %d)", 9392108Sphk pp, pp->name, error); 9492108Sphk KASSERT(error != 0, 9592108Sphk ("g_orphan_provider(%p(%s), 0) error must be non-zero\n", 9692108Sphk pp, pp->name)); 9792108Sphk pp->error = error; 98104053Sphk mtx_lock(&g_eventlock); 9992108Sphk TAILQ_INSERT_TAIL(&g_doorstep, pp, orphan); 100104053Sphk mtx_unlock(&g_eventlock); 10192108Sphk wakeup(&g_wait_event); 10292108Sphk} 10392108Sphk 10492108Sphk/* 10592108Sphk * This function is called once on each provider which the event handler 10692108Sphk * finds on its g_doorstep. 10792108Sphk */ 10892108Sphk 10992108Sphkstatic void 11093250Sphkg_orphan_register(struct g_provider *pp) 11192108Sphk{ 11292108Sphk struct g_consumer *cp, *cp2; 11392108Sphk 11492108Sphk g_trace(G_T_TOPOLOGY, "g_orphan_register(%s)", pp->name); 11592108Sphk g_topology_assert(); 11692108Sphk 11792108Sphk /* 11892108Sphk * Tell all consumers the bad news. 11992108Sphk * Don't get surprised if they self-destruct. 12092108Sphk */ 12192108Sphk cp = LIST_FIRST(&pp->consumers); 12292108Sphk while (cp != NULL) { 12392108Sphk cp2 = LIST_NEXT(cp, consumers); 12493776Sphk KASSERT(cp->geom->orphan != NULL, 12593776Sphk ("geom %s has no orphan, class %s", 12693776Sphk cp->geom->name, cp->geom->class->name)); 12793776Sphk cp->geom->orphan(cp); 12892108Sphk cp = cp2; 12992108Sphk } 13092108Sphk} 13192108Sphk 13292108Sphkstatic void 13392108Sphkg_destroy_event(struct g_event *ep) 13492108Sphk{ 13592108Sphk 13692108Sphk g_free(ep); 13792108Sphk} 13892108Sphk 13992108Sphkstatic void 14093250Sphkg_do_event(struct g_event *ep) 14192108Sphk{ 14293248Sphk struct g_class *mp, *mp2; 14392108Sphk struct g_geom *gp; 14492108Sphk struct g_consumer *cp, *cp2; 14592108Sphk struct g_provider *pp; 14692108Sphk int i; 14792108Sphk 14892108Sphk g_trace(G_T_TOPOLOGY, "g_do_event(%p) %d m:%p g:%p p:%p c:%p - ", 14993248Sphk ep, ep->event, ep->class, ep->geom, ep->provider, ep->consumer); 15092108Sphk g_topology_assert(); 15192108Sphk switch (ep->event) { 15293248Sphk case EV_NEW_CLASS: 15393248Sphk mp2 = ep->class; 15492108Sphk if (mp2->taste == NULL) 15592108Sphk break; 15693774Sphk LIST_FOREACH(mp, &g_classes, class) { 15792108Sphk if (mp2 == mp) 15892108Sphk continue; 15992108Sphk LIST_FOREACH(gp, &mp->geom, geom) { 16092108Sphk LIST_FOREACH(pp, &gp->provider, provider) { 16193250Sphk mp2->taste(ep->class, pp, 0); 16292108Sphk g_topology_assert(); 16392108Sphk } 16492108Sphk } 16592108Sphk } 16692108Sphk break; 16792108Sphk case EV_NEW_PROVIDER: 16892108Sphk g_trace(G_T_TOPOLOGY, "EV_NEW_PROVIDER(%s)", 16992108Sphk ep->provider->name); 17093774Sphk LIST_FOREACH(mp, &g_classes, class) { 17192108Sphk if (mp->taste == NULL) 17292108Sphk continue; 17392108Sphk i = 1; 17492108Sphk LIST_FOREACH(cp, &ep->provider->consumers, consumers) 17593248Sphk if(cp->geom->class == mp) 17692108Sphk i = 0; 17792108Sphk if (i) { 17893250Sphk mp->taste(mp, ep->provider, 0); 17992108Sphk g_topology_assert(); 18092108Sphk } 18192108Sphk } 18292108Sphk break; 18392108Sphk case EV_SPOILED: 18492108Sphk g_trace(G_T_TOPOLOGY, "EV_SPOILED(%p(%s),%p)", 18592108Sphk ep->provider, ep->provider->name, ep->consumer); 18692108Sphk cp = LIST_FIRST(&ep->provider->consumers); 18792108Sphk while (cp != NULL) { 18892108Sphk cp2 = LIST_NEXT(cp, consumers); 18992108Sphk if (cp->spoiled) { 19092108Sphk g_trace(G_T_TOPOLOGY, "spoiling %p (%s) (%p)", 19192108Sphk cp, cp->geom->name, cp->geom->spoiled); 19292108Sphk if (cp->geom->spoiled != NULL) 19392108Sphk cp->geom->spoiled(cp); 19497316Sphk else 19597316Sphk cp->spoiled = 0; 19692108Sphk } 19792108Sphk cp = cp2; 19892108Sphk } 19992108Sphk break; 20092108Sphk case EV_LAST: 20192108Sphk default: 20292108Sphk KASSERT(1 == 0, ("Unknown event %d", ep->event)); 20392108Sphk } 20492108Sphk} 20592108Sphk 20692108Sphkstatic int 20793250Sphkone_event(void) 20892108Sphk{ 20992108Sphk struct g_event *ep; 21092108Sphk struct g_provider *pp; 21192108Sphk 21292108Sphk g_topology_lock(); 21392108Sphk for (;;) { 214104053Sphk mtx_lock(&g_eventlock); 21592108Sphk pp = TAILQ_FIRST(&g_doorstep); 21692108Sphk if (pp != NULL) 21792108Sphk TAILQ_REMOVE(&g_doorstep, pp, orphan); 218104053Sphk mtx_unlock(&g_eventlock); 21992108Sphk if (pp == NULL) 22092108Sphk break; 22193250Sphk g_orphan_register(pp); 22292108Sphk } 22392108Sphk ep = TAILQ_FIRST(&g_events); 22492108Sphk if (ep == NULL) { 22592108Sphk g_topology_unlock(); 22692108Sphk return (0); 22792108Sphk } 22892108Sphk TAILQ_REMOVE(&g_events, ep, events); 22993248Sphk if (ep->class != NULL) 23093248Sphk ep->class->event = NULL; 23192108Sphk if (ep->geom != NULL) 23292108Sphk ep->geom->event = NULL; 23392108Sphk if (ep->provider != NULL) 23492108Sphk ep->provider->event = NULL; 23592108Sphk if (ep->consumer != NULL) 23692108Sphk ep->consumer->event = NULL; 23793250Sphk g_do_event(ep); 23892108Sphk g_pending_events--; 23992108Sphk if (g_pending_events == 0) { 24092108Sphk wakeup(&g_pending_events); 24192108Sphk } 24292108Sphk g_topology_unlock(); 24392108Sphk g_destroy_event(ep); 24492108Sphk return (1); 24592108Sphk} 24692108Sphk 24792108Sphkvoid 24893250Sphkg_run_events() 24992108Sphk{ 25092108Sphk 25193250Sphk while (one_event()) 25292108Sphk ; 25392108Sphk} 25492108Sphk 25592108Sphkvoid 25693248Sphkg_post_event(enum g_events ev, struct g_class *mp, struct g_geom *gp, struct g_provider *pp, struct g_consumer *cp) 25792108Sphk{ 25892108Sphk struct g_event *ep; 25992108Sphk 26092108Sphk g_trace(G_T_TOPOLOGY, "g_post_event(%d, %p, %p, %p, %p)", 26192108Sphk ev, mp, gp, pp, cp); 26292108Sphk g_topology_assert(); 26392108Sphk ep = g_malloc(sizeof *ep, M_WAITOK | M_ZERO); 26492108Sphk ep->event = ev; 26592108Sphk if (mp != NULL) { 26693248Sphk ep->class = mp; 26793248Sphk KASSERT(mp->event == NULL, ("Double event on class")); 26892108Sphk mp->event = ep; 26992108Sphk } 27092108Sphk if (gp != NULL) { 27192108Sphk ep->geom = gp; 27292108Sphk KASSERT(gp->event == NULL, ("Double event on geom")); 27392108Sphk gp->event = ep; 27492108Sphk } 27592108Sphk if (pp != NULL) { 27692108Sphk ep->provider = pp; 27792108Sphk KASSERT(pp->event == NULL, ("Double event on provider")); 27892108Sphk pp->event = ep; 27992108Sphk } 28092108Sphk if (cp != NULL) { 28192108Sphk ep->consumer = cp; 28292108Sphk KASSERT(cp->event == NULL, ("Double event on consumer")); 28392108Sphk cp->event = ep; 28492108Sphk } 28592108Sphk g_pending_events++; 28692108Sphk TAILQ_INSERT_TAIL(&g_events, ep, events); 28792108Sphk wakeup(&g_wait_event); 28892108Sphk} 28992108Sphk 29092108Sphkvoid 29192108Sphkg_event_init() 29292108Sphk{ 29392108Sphk 294104053Sphk mtx_init(&g_eventlock, "GEOM orphanage", NULL, MTX_DEF); 29592108Sphk} 296