1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2002 Poul-Henning Kamp 5 * Copyright (c) 2002 Networks Associates Technology, Inc. 6 * All rights reserved. 7 * 8 * This software was developed for the FreeBSD Project by Poul-Henning Kamp 9 * and NAI Labs, the Security Research Division of Network Associates, Inc. 10 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 11 * DARPA CHATS research program. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. The names of the authors may not be used to endorse or promote 22 * products derived from this software without specific prior written 23 * permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 */ 37 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/eventhandler.h> 45 #include <sys/malloc.h> 46 #include <sys/bio.h> 47 #include <sys/sysctl.h> 48 #include <sys/proc.h> 49 #include <sys/unistd.h> 50 #include <sys/kthread.h> 51 #include <sys/lock.h> 52 #include <sys/mutex.h> 53 #include <sys/sbuf.h> 54 #include <sys/sched.h> 55 #include <sys/sx.h> 56 #include <geom/geom.h> 57 #include <geom/geom_int.h> 58 59 MALLOC_DEFINE(M_GEOM, "GEOM", "Geom data structures"); 60 61 struct sx topology_lock; 62 63 static struct proc *g_proc; 64 static struct thread __read_mostly *g_up_td; 65 static struct thread __read_mostly *g_down_td; 66 static struct thread __read_mostly *g_event_td; 67 68 int __read_mostly g_debugflags; 69 int __read_mostly g_collectstats = G_STATS_PROVIDERS; 70 int g_shutdown; 71 int g_notaste; 72 73 /* 74 * G_UP and G_DOWN are the two threads which push I/O through the 75 * stack. 76 * 77 * Things are procesed in a FIFO order, but these threads could be 78 * part of I/O prioritization by deciding which bios/bioqs to service 79 * in what order. 80 * 81 * We have only one thread in each direction, it is believed that until 82 * a very non-trivial workload in the UP/DOWN path this will be enough, 83 * but more than one can actually be run without problems. 84 * 85 * Holding the "mymutex" is a debugging feature: It prevents people 86 * from sleeping in the UP/DOWN I/O path by mistake or design (doing 87 * so almost invariably result in deadlocks since it stalls all I/O 88 * processing in the given direction. 89 */ 90 91 static void 92 g_up_procbody(void *arg) 93 { 94 95 thread_lock(g_up_td); 96 sched_prio(g_up_td, PRIBIO); 97 thread_unlock(g_up_td); 98 for(;;) { 99 g_io_schedule_up(g_up_td); 100 } 101 } 102 103 static void 104 g_down_procbody(void *arg) 105 { 106 107 thread_lock(g_down_td); 108 sched_prio(g_down_td, PRIBIO); 109 thread_unlock(g_down_td); 110 for(;;) { 111 g_io_schedule_down(g_down_td); 112 } 113 } 114 115 static void 116 g_event_procbody(void *arg) 117 { 118 119 thread_lock(g_event_td); 120 sched_prio(g_event_td, PRIBIO); 121 thread_unlock(g_event_td); 122 g_run_events(); 123 /* NOTREACHED */ 124 } 125 126 int 127 g_is_geom_thread(struct thread *td) 128 { 129 130 return (td == g_up_td || td == g_down_td || td == g_event_td); 131 } 132 133 static void 134 geom_shutdown(void *foo __unused) 135 { 136 137 g_shutdown = 1; 138 } 139 140 void 141 g_init(void) 142 { 143 144 g_trace(G_T_TOPOLOGY, "g_ignition"); 145 sx_init(&topology_lock, "GEOM topology"); 146 g_io_init(); 147 g_event_init(); 148 g_ctl_init(); 149 kproc_kthread_add(g_event_procbody, NULL, &g_proc, &g_event_td, 150 RFHIGHPID, 0, "geom", "g_event"); 151 kproc_kthread_add(g_up_procbody, NULL, &g_proc, &g_up_td, 152 RFHIGHPID, 0, "geom", "g_up"); 153 kproc_kthread_add(g_down_procbody, NULL, &g_proc, &g_down_td, 154 RFHIGHPID, 0, "geom", "g_down"); 155 EVENTHANDLER_REGISTER(shutdown_pre_sync, geom_shutdown, NULL, 156 SHUTDOWN_PRI_FIRST); 157 } 158 159 static int 160 sysctl_kern_geom_confany(struct sysctl_req *req, g_event_t *func, size_t *hint) 161 { 162 size_t len = 0; 163 int error = 0; 164 struct sbuf *sb; 165 166 if (req->oldptr == NULL) { 167 sb = sbuf_new(NULL, NULL, PAGE_SIZE, SBUF_FIXEDLEN | 168 SBUF_INCLUDENUL); 169 sbuf_set_drain(sb, sbuf_count_drain, &len); 170 g_waitfor_event(func, sb, M_WAITOK, NULL); 171 req->oldidx = *hint = len; 172 } else { 173 sb = sbuf_new(NULL, NULL, *hint, SBUF_AUTOEXTEND | 174 SBUF_INCLUDENUL); 175 g_waitfor_event(func, sb, M_WAITOK, NULL); 176 *hint = sbuf_len(sb); 177 error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb)); 178 } 179 sbuf_delete(sb); 180 return error; 181 } 182 183 static int 184 sysctl_kern_geom_conftxt(SYSCTL_HANDLER_ARGS) 185 { 186 static size_t hint = PAGE_SIZE; 187 188 return (sysctl_kern_geom_confany(req, g_conftxt, &hint)); 189 } 190 191 static int 192 sysctl_kern_geom_confdot(SYSCTL_HANDLER_ARGS) 193 { 194 static size_t hint = PAGE_SIZE; 195 196 return (sysctl_kern_geom_confany(req, g_confdot, &hint)); 197 } 198 199 static int 200 sysctl_kern_geom_confxml(SYSCTL_HANDLER_ARGS) 201 { 202 static size_t hint = PAGE_SIZE; 203 204 return (sysctl_kern_geom_confany(req, g_confxml, &hint)); 205 } 206 207 SYSCTL_NODE(_kern, OID_AUTO, geom, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 208 "GEOMetry management"); 209 210 SYSCTL_PROC(_kern_geom, OID_AUTO, confxml, 211 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 0, 0, 212 sysctl_kern_geom_confxml, "", 213 "Dump the GEOM config in XML"); 214 215 SYSCTL_PROC(_kern_geom, OID_AUTO, confdot, 216 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 0, 0, 217 sysctl_kern_geom_confdot, "", 218 "Dump the GEOM config in dot"); 219 220 SYSCTL_PROC(_kern_geom, OID_AUTO, conftxt, 221 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, 0, 0, 222 sysctl_kern_geom_conftxt, "", 223 "Dump the GEOM config in txt"); 224 225 SYSCTL_INT(_kern_geom, OID_AUTO, debugflags, CTLFLAG_RWTUN, 226 &g_debugflags, 0, "Set various trace levels for GEOM debugging"); 227 228 SYSCTL_INT(_kern_geom, OID_AUTO, notaste, CTLFLAG_RW, 229 &g_notaste, 0, "Prevent GEOM tasting"); 230 231 SYSCTL_INT(_kern_geom, OID_AUTO, collectstats, CTLFLAG_RW, 232 &g_collectstats, 0, 233 "Control statistics collection on GEOM providers and consumers"); 234 235 SYSCTL_INT(_debug_sizeof, OID_AUTO, g_class, CTLFLAG_RD, 236 SYSCTL_NULL_INT_PTR, sizeof(struct g_class), "sizeof(struct g_class)"); 237 SYSCTL_INT(_debug_sizeof, OID_AUTO, g_geom, CTLFLAG_RD, 238 SYSCTL_NULL_INT_PTR, sizeof(struct g_geom), "sizeof(struct g_geom)"); 239 SYSCTL_INT(_debug_sizeof, OID_AUTO, g_provider, CTLFLAG_RD, 240 SYSCTL_NULL_INT_PTR, sizeof(struct g_provider), "sizeof(struct g_provider)"); 241 SYSCTL_INT(_debug_sizeof, OID_AUTO, g_consumer, CTLFLAG_RD, 242 SYSCTL_NULL_INT_PTR, sizeof(struct g_consumer), "sizeof(struct g_consumer)"); 243 SYSCTL_INT(_debug_sizeof, OID_AUTO, g_bioq, CTLFLAG_RD, 244 SYSCTL_NULL_INT_PTR, sizeof(struct g_bioq), "sizeof(struct g_bioq)"); 245