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 * $FreeBSD$ 36 */ 37 38 /* 39 * XXX: How do we in general know that objects referenced in events 40 * have not been destroyed before we get around to handle the event ? 41 */ 42 43 #include <sys/param.h> 44 #ifndef _KERNEL 45 #include <stdio.h> 46 #include <unistd.h> 47 #include <string.h> 48 #include <stdlib.h> 49 #include <signal.h> 50 #include <err.h> 51 #else 52 #include <sys/malloc.h> 53 #include <sys/systm.h> 54 #include <sys/kernel.h> 55 #include <sys/lock.h> 56 #include <sys/mutex.h> 57 #endif 58 #include <sys/errno.h> 59 #include <sys/time.h> 60 #include <geom/geom.h> 61 #include <geom/geom_int.h> 62 63 static struct event_tailq_head g_events = TAILQ_HEAD_INITIALIZER(g_events); 64 static u_int g_pending_events, g_silence_events; 65 static void g_do_event(struct g_event *ep); 66 static TAILQ_HEAD(,g_provider) g_doorstep = TAILQ_HEAD_INITIALIZER(g_doorstep); 67 static struct mtx g_doorlock; 68 69 void 70 g_silence(void) 71 { 72 73 g_silence_events = 1; 74 } 75 76 void 77 g_waitidle(void) 78 { 79 80 g_silence_events = 0; 81 mtx_lock(&Giant); 82 wakeup(&g_silence_events); 83 while (g_pending_events) 84 tsleep(&g_pending_events, PPAUSE, "g_waitidle", hz/5); 85 mtx_unlock(&Giant); 86 } 87 88 void 89 g_orphan_provider(struct g_provider *pp, int error) 90 { 91 92 g_trace(G_T_TOPOLOGY, "g_orphan_provider(%p(%s), %d)", 93 pp, pp->name, error); 94 KASSERT(error != 0, 95 ("g_orphan_provider(%p(%s), 0) error must be non-zero\n", 96 pp, pp->name)); 97 pp->error = error; 98 mtx_lock(&g_doorlock); 99 TAILQ_INSERT_TAIL(&g_doorstep, pp, orphan); 100 mtx_unlock(&g_doorlock); 101 wakeup(&g_wait_event); 102 } 103 104 /* 105 * This function is called once on each provider which the event handler 106 * finds on its g_doorstep. 107 */ 108 109 static void 110 g_orphan_register(struct g_provider *pp) 111 { 112 struct g_consumer *cp, *cp2; 113 114 g_trace(G_T_TOPOLOGY, "g_orphan_register(%s)", pp->name); 115 g_topology_assert(); 116 117 /* 118 * Tell all consumers the bad news. 119 * Don't get surprised if they self-destruct. 120 */ 121 cp = LIST_FIRST(&pp->consumers); 122 while (cp != NULL) { 123 cp2 = LIST_NEXT(cp, consumers); 124 KASSERT(cp->geom->orphan != NULL, 125 ("geom %s has no orphan, class %s", 126 cp->geom->name, cp->geom->class->name)); 127 cp->geom->orphan(cp); 128 cp = cp2; 129 } 130 } 131 132 static void 133 g_destroy_event(struct g_event *ep) 134 { 135 136 g_free(ep); 137 } 138 139 static void 140 g_do_event(struct g_event *ep) 141 { 142 struct g_class *mp, *mp2; 143 struct g_geom *gp; 144 struct g_consumer *cp, *cp2; 145 struct g_provider *pp; 146 int i; 147 148 g_trace(G_T_TOPOLOGY, "g_do_event(%p) %d m:%p g:%p p:%p c:%p - ", 149 ep, ep->event, ep->class, ep->geom, ep->provider, ep->consumer); 150 g_topology_assert(); 151 switch (ep->event) { 152 case EV_NEW_CLASS: 153 mp2 = ep->class; 154 if (mp2->taste == NULL) 155 break; 156 LIST_FOREACH(mp, &g_classes, class) { 157 if (mp2 == mp) 158 continue; 159 LIST_FOREACH(gp, &mp->geom, geom) { 160 LIST_FOREACH(pp, &gp->provider, provider) { 161 mp2->taste(ep->class, pp, 0); 162 g_topology_assert(); 163 } 164 } 165 } 166 break; 167 case EV_NEW_PROVIDER: 168 g_trace(G_T_TOPOLOGY, "EV_NEW_PROVIDER(%s)", 169 ep->provider->name); 170 LIST_FOREACH(mp, &g_classes, class) { 171 if (mp->taste == NULL) 172 continue; 173 i = 1; 174 LIST_FOREACH(cp, &ep->provider->consumers, consumers) 175 if(cp->geom->class == mp) 176 i = 0; 177 if (i) { 178 mp->taste(mp, ep->provider, 0); 179 g_topology_assert(); 180 } 181 } 182 break; 183 case EV_SPOILED: 184 g_trace(G_T_TOPOLOGY, "EV_SPOILED(%p(%s),%p)", 185 ep->provider, ep->provider->name, ep->consumer); 186 cp = LIST_FIRST(&ep->provider->consumers); 187 while (cp != NULL) { 188 cp2 = LIST_NEXT(cp, consumers); 189 if (cp->spoiled) { 190 g_trace(G_T_TOPOLOGY, "spoiling %p (%s) (%p)", 191 cp, cp->geom->name, cp->geom->spoiled); 192 if (cp->geom->spoiled != NULL) 193 cp->geom->spoiled(cp); 194 else 195 cp->spoiled = 0; 196 } 197 cp = cp2; 198 } 199 break; 200 case EV_LAST: 201 default: 202 KASSERT(1 == 0, ("Unknown event %d", ep->event)); 203 } 204 } 205 206 static int 207 one_event(void) 208 { 209 struct g_event *ep; 210 struct g_provider *pp; 211 212 g_topology_lock(); 213 for (;;) { 214 mtx_lock(&g_doorlock); 215 pp = TAILQ_FIRST(&g_doorstep); 216 if (pp != NULL) 217 TAILQ_REMOVE(&g_doorstep, pp, orphan); 218 mtx_unlock(&g_doorlock); 219 if (pp == NULL) 220 break; 221 g_orphan_register(pp); 222 } 223 ep = TAILQ_FIRST(&g_events); 224 if (ep == NULL) { 225 g_topology_unlock(); 226 return (0); 227 } 228 TAILQ_REMOVE(&g_events, ep, events); 229 if (ep->class != NULL) 230 ep->class->event = NULL; 231 if (ep->geom != NULL) 232 ep->geom->event = NULL; 233 if (ep->provider != NULL) 234 ep->provider->event = NULL; 235 if (ep->consumer != NULL) 236 ep->consumer->event = NULL; 237 g_do_event(ep); 238 g_pending_events--; 239 if (g_pending_events == 0) { 240 wakeup(&g_pending_events); 241 } 242 g_topology_unlock(); 243 g_destroy_event(ep); 244 return (1); 245 } 246 247 void 248 g_run_events() 249 { 250 251 while (one_event()) 252 ; 253 } 254 255 void 256 g_post_event(enum g_events ev, struct g_class *mp, struct g_geom *gp, struct g_provider *pp, struct g_consumer *cp) 257 { 258 struct g_event *ep; 259 260 g_trace(G_T_TOPOLOGY, "g_post_event(%d, %p, %p, %p, %p)", 261 ev, mp, gp, pp, cp); 262 g_topology_assert(); 263 ep = g_malloc(sizeof *ep, M_WAITOK | M_ZERO); 264 ep->event = ev; 265 if (mp != NULL) { 266 ep->class = mp; 267 KASSERT(mp->event == NULL, ("Double event on class")); 268 mp->event = ep; 269 } 270 if (gp != NULL) { 271 ep->geom = gp; 272 KASSERT(gp->event == NULL, ("Double event on geom")); 273 gp->event = ep; 274 } 275 if (pp != NULL) { 276 ep->provider = pp; 277 KASSERT(pp->event == NULL, ("Double event on provider")); 278 pp->event = ep; 279 } 280 if (cp != NULL) { 281 ep->consumer = cp; 282 KASSERT(cp->event == NULL, ("Double event on consumer")); 283 cp->event = ep; 284 } 285 g_pending_events++; 286 TAILQ_INSERT_TAIL(&g_events, ep, events); 287 wakeup(&g_wait_event); 288 } 289 290 void 291 g_event_init() 292 { 293 294 mtx_init(&g_doorlock, "GEOM orphanage", NULL, MTX_DEF); 295 } 296