geom_kern.c revision 113937
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: head/sys/geom/geom_kern.c 113937 2003-04-23 20:46:12Z phk $ 36 */ 37 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/kernel.h> 41#include <sys/eventhandler.h> 42#include <sys/malloc.h> 43#include <sys/bio.h> 44#include <sys/sysctl.h> 45#include <sys/proc.h> 46#include <sys/kthread.h> 47#include <sys/lock.h> 48#include <sys/mutex.h> 49#include <sys/sx.h> 50#include <sys/sbuf.h> 51#include <geom/geom.h> 52#include <geom/geom_int.h> 53 54MALLOC_DEFINE(M_GEOM, "GEOM", "Geom data structures"); 55 56struct sx topology_lock; 57 58static struct proc *g_up_proc; 59 60int g_debugflags; 61int g_collectstats = 1; 62int g_shutdown; 63 64/* 65 * G_UP and G_DOWN are the two threads which push I/O through the 66 * stack. 67 * 68 * Things are procesed in a FIFO order, but these threads could be 69 * part of I/O prioritization by deciding which bios/bioqs to service 70 * in what order. 71 * 72 * We have only one thread in each direction, it is belived that until 73 * a very non-trivial workload in the UP/DOWN path this will be enough, 74 * but more than one can actually be run without problems. 75 * 76 * Holding the "mymutex" is a debugging feature: It prevents people 77 * from sleeping in the UP/DOWN I/O path by mistake or design (doing 78 * so almost invariably result in deadlocks since it stalls all I/O 79 * processing in the given direction. 80 */ 81 82static void 83g_up_procbody(void) 84{ 85 struct proc *p = g_up_proc; 86 struct thread *tp = FIRST_THREAD_IN_PROC(p); 87 88 mtx_assert(&Giant, MA_NOTOWNED); 89 tp->td_base_pri = PRIBIO; 90 for(;;) { 91 g_io_schedule_up(tp); 92 } 93} 94 95struct kproc_desc g_up_kp = { 96 "g_up", 97 g_up_procbody, 98 &g_up_proc, 99}; 100 101static struct proc *g_down_proc; 102 103static void 104g_down_procbody(void) 105{ 106 struct proc *p = g_down_proc; 107 struct thread *tp = FIRST_THREAD_IN_PROC(p); 108 109 mtx_assert(&Giant, MA_NOTOWNED); 110 tp->td_base_pri = PRIBIO; 111 for(;;) { 112 g_io_schedule_down(tp); 113 } 114} 115 116struct kproc_desc g_down_kp = { 117 "g_down", 118 g_down_procbody, 119 &g_down_proc, 120}; 121 122static struct proc *g_event_proc; 123 124static void 125g_event_procbody(void) 126{ 127 struct proc *p = g_event_proc; 128 struct thread *tp = FIRST_THREAD_IN_PROC(p); 129 130 mtx_assert(&Giant, MA_NOTOWNED); 131 tp->td_base_pri = PRIBIO; 132 for(;;) { 133 g_run_events(); 134 tsleep(&g_wait_event, PRIBIO, "g_events", hz/10); 135 } 136} 137 138struct kproc_desc g_event_kp = { 139 "g_event", 140 g_event_procbody, 141 &g_event_proc, 142}; 143 144static void 145geom_shutdown(void *foo __unused) 146{ 147 148 g_shutdown = 1; 149} 150 151void 152g_init(void) 153{ 154 sx_init(&topology_lock, "GEOM topology"); 155 g_io_init(); 156 g_event_init(); 157 g_ctl_init(); 158 mtx_lock(&Giant); 159 kproc_start(&g_event_kp); 160 kproc_start(&g_up_kp); 161 kproc_start(&g_down_kp); 162 mtx_unlock(&Giant); 163 EVENTHANDLER_REGISTER(shutdown_pre_sync, geom_shutdown, NULL, 164 SHUTDOWN_PRI_FIRST); 165} 166 167static int 168sysctl_kern_geom_conftxt(SYSCTL_HANDLER_ARGS) 169{ 170 int error; 171 struct sbuf *sb; 172 173 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 174 sbuf_clear(sb); 175 g_post_event(g_conftxt, sb, M_WAITOK, NULL); 176 do { 177 tsleep(sb, PZERO, "g_conftxt", hz); 178 } while(!sbuf_done(sb)); 179 error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1); 180 sbuf_delete(sb); 181 return error; 182} 183 184static int 185sysctl_kern_geom_confdot(SYSCTL_HANDLER_ARGS) 186{ 187 int error; 188 struct sbuf *sb; 189 190 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 191 sbuf_clear(sb); 192 g_post_event(g_confdot, sb, M_WAITOK, NULL); 193 do { 194 tsleep(sb, PZERO, "g_confdot", hz); 195 } while(!sbuf_done(sb)); 196 error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1); 197 sbuf_delete(sb); 198 return error; 199} 200 201static int 202sysctl_kern_geom_confxml(SYSCTL_HANDLER_ARGS) 203{ 204 int error; 205 struct sbuf *sb; 206 207 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 208 sbuf_clear(sb); 209 g_post_event(g_confxml, sb, M_WAITOK, NULL); 210 do { 211 tsleep(sb, PZERO, "g_confxml", hz); 212 } while(!sbuf_done(sb)); 213 error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1); 214 sbuf_delete(sb); 215 return error; 216} 217 218SYSCTL_NODE(_kern, OID_AUTO, geom, CTLFLAG_RW, 0, "GEOMetry management"); 219 220SYSCTL_PROC(_kern_geom, OID_AUTO, confxml, CTLTYPE_STRING|CTLFLAG_RD, 221 0, 0, sysctl_kern_geom_confxml, "", 222 "Dump the GEOM config in XML"); 223 224SYSCTL_PROC(_kern_geom, OID_AUTO, confdot, CTLTYPE_STRING|CTLFLAG_RD, 225 0, 0, sysctl_kern_geom_confdot, "", 226 "Dump the GEOM config in dot"); 227 228SYSCTL_PROC(_kern_geom, OID_AUTO, conftxt, CTLTYPE_STRING|CTLFLAG_RD, 229 0, 0, sysctl_kern_geom_conftxt, "", 230 "Dump the GEOM config in txt"); 231 232SYSCTL_INT(_kern_geom, OID_AUTO, debugflags, CTLFLAG_RW, 233 &g_debugflags, 0, ""); 234 235SYSCTL_INT(_kern_geom, OID_AUTO, collectstats, CTLFLAG_RW, 236 &g_collectstats, 0, ""); 237 238SYSCTL_INT(_debug_sizeof, OID_AUTO, g_class, CTLFLAG_RD, 239 0, sizeof(struct g_class), ""); 240SYSCTL_INT(_debug_sizeof, OID_AUTO, g_geom, CTLFLAG_RD, 241 0, sizeof(struct g_geom), ""); 242SYSCTL_INT(_debug_sizeof, OID_AUTO, g_provider, CTLFLAG_RD, 243 0, sizeof(struct g_provider), ""); 244SYSCTL_INT(_debug_sizeof, OID_AUTO, g_consumer, CTLFLAG_RD, 245 0, sizeof(struct g_consumer), ""); 246SYSCTL_INT(_debug_sizeof, OID_AUTO, g_bioq, CTLFLAG_RD, 247 0, sizeof(struct g_bioq), ""); 248SYSCTL_INT(_debug_sizeof, OID_AUTO, g_event, CTLFLAG_RD, 249 0, sizeof(struct g_event), ""); 250