geom_kern.c revision 104087
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 104087 2002-09-28 11:57:20Z phk $ 36 */ 37 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/kernel.h> 41#include <sys/malloc.h> 42#include <sys/bio.h> 43#include <sys/sysctl.h> 44#include <sys/proc.h> 45#include <sys/kthread.h> 46#include <sys/lock.h> 47#include <sys/mutex.h> 48#include <sys/sx.h> 49#include <sys/sbuf.h> 50#include <geom/geom.h> 51#include <geom/geom_int.h> 52 53MALLOC_DEFINE(M_GEOM, "GEOM", "Geom data structures"); 54 55struct sx topology_lock; 56 57static struct proc *g_up_proc; 58 59int g_debugflags; 60 61/* 62 * G_UP and G_DOWN are the two threads which push I/O through the 63 * stack. 64 * 65 * Things are procesed in a FIFO order, but these threads could be 66 * part of I/O prioritization by deciding which bios/bioqs to service 67 * in what order. 68 * 69 * We have only one thread in each direction, it is belived that until 70 * a very non-trivial workload in the UP/DOWN path this will be enough, 71 * but more than one can actually be run without problems. 72 * 73 * Holding the "mymutex" is a debugging feature: It prevents people 74 * from sleeping in the UP/DOWN I/O path by mistake or design (doing 75 * so almost invariably result in deadlocks since it stalls all I/O 76 * processing in the given direction. 77 */ 78 79static void 80g_up_procbody(void) 81{ 82 struct proc *p = g_up_proc; 83 struct thread *tp = FIRST_THREAD_IN_PROC(p); 84 struct mtx mymutex; 85 86 mtx_init(&mymutex, "g_up", MTX_DEF, 0); 87 mtx_lock(&mymutex); 88 tp->td_base_pri = PRIBIO; 89 for(;;) { 90 g_io_schedule_up(tp); 91 msleep(&g_wait_up, &mymutex, PRIBIO, "g_up", hz/10); 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 struct mtx mymutex; 109 110 mtx_init(&mymutex, "g_down", MTX_DEF, 0); 111 mtx_lock(&mymutex); 112 tp->td_base_pri = PRIBIO; 113 for(;;) { 114 g_io_schedule_down(tp); 115 msleep(&g_wait_down, &mymutex, PRIBIO, "g_down", hz/10); 116 } 117} 118 119struct kproc_desc g_down_kp = { 120 "g_down", 121 g_down_procbody, 122 &g_down_proc, 123}; 124 125static struct proc *g_event_proc; 126 127static void 128g_event_procbody(void) 129{ 130 struct proc *p = g_down_proc; 131 struct thread *tp = FIRST_THREAD_IN_PROC(p); 132 133 tp->td_base_pri = PRIBIO; 134 for(;;) { 135 g_run_events(); 136 tsleep(&g_wait_event, PRIBIO, "g_events", hz/10); 137 } 138} 139 140struct kproc_desc g_event_kp = { 141 "g_event", 142 g_event_procbody, 143 &g_event_proc, 144}; 145 146void 147g_init(void) 148{ 149 printf("Initializing GEOMetry subsystem\n"); 150 if (bootverbose) 151 g_debugflags |= G_T_TOPOLOGY; 152 sx_init(&topology_lock, "GEOM topology"); 153 g_io_init(); 154 g_event_init(); 155 mtx_lock(&Giant); 156 kproc_start(&g_event_kp); 157 kproc_start(&g_up_kp); 158 kproc_start(&g_down_kp); 159 mtx_unlock(&Giant); 160} 161 162static int 163sysctl_debug_geomdot(SYSCTL_HANDLER_ARGS) 164{ 165 int i, error; 166 struct sbuf *sb; 167 168 i = 0; 169 sb = g_confdot(); 170 error = sysctl_handle_opaque(oidp, sbuf_data(sb), sbuf_len(sb), req); 171 sbuf_delete(sb); 172 return (error); 173} 174 175SYSCTL_PROC(_debug, OID_AUTO, geomdot, CTLTYPE_STRING|CTLFLAG_RD, 176 0, 0, sysctl_debug_geomdot, "A", 177 "Dump the GEOM config"); 178 179static int 180sysctl_debug_geomconf(SYSCTL_HANDLER_ARGS) 181{ 182 int i, error; 183 struct sbuf *sb; 184 185 i = 0; 186 sb = g_conf(); 187 error = sysctl_handle_opaque(oidp, sbuf_data(sb), sbuf_len(sb), req); 188 sbuf_delete(sb); 189 return (error); 190} 191 192SYSCTL_PROC(_debug, OID_AUTO, geomconf, CTLTYPE_STRING|CTLFLAG_RD, 193 0, 0, sysctl_debug_geomconf, "A", 194 "Dump the GEOM config"); 195 196SYSCTL_INT(_debug, OID_AUTO, geomdebugflags, CTLTYPE_INT|CTLFLAG_RW, 197 &g_debugflags, 0, ""); 198 199SYSCTL_INT(_debug_sizeof, OID_AUTO, g_class, CTLTYPE_INT|CTLFLAG_RD, 200 0, sizeof(struct g_class), ""); 201SYSCTL_INT(_debug_sizeof, OID_AUTO, g_geom, CTLTYPE_INT|CTLFLAG_RD, 202 0, sizeof(struct g_geom), ""); 203SYSCTL_INT(_debug_sizeof, OID_AUTO, g_provider, CTLTYPE_INT|CTLFLAG_RD, 204 0, sizeof(struct g_provider), ""); 205SYSCTL_INT(_debug_sizeof, OID_AUTO, g_consumer, CTLTYPE_INT|CTLFLAG_RD, 206 0, sizeof(struct g_consumer), ""); 207SYSCTL_INT(_debug_sizeof, OID_AUTO, g_bioq, CTLTYPE_INT|CTLFLAG_RD, 208 0, sizeof(struct g_bioq), ""); 209SYSCTL_INT(_debug_sizeof, OID_AUTO, g_event, CTLTYPE_INT|CTLFLAG_RD, 210 0, sizeof(struct g_event), ""); 211