geom_kern.c revision 104063
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 104063 2002-09-27 21:24:40Z 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 <sys/errno.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; 61 62/* 63 * G_UP and G_DOWN are the two threads which push I/O through the 64 * stack. 65 * 66 * Things are procesed in a FIFO order, but these threads could be 67 * part of I/O prioritization by deciding which bios/bioqs to service 68 * in what order. 69 * 70 * We have only one thread in each direction, it is belived that until 71 * a very non-trivial workload in the UP/DOWN path this will be enough, 72 * but more than one can actually be run without problems. 73 * 74 * Holding the "mymutex" is a debugging feature: It prevents people 75 * from sleeping in the UP/DOWN I/O path by mistake or design (doing 76 * so almost invariably result in deadlocks since it stalls all I/O 77 * processing in the given direction. 78 */ 79 80static void 81g_up_procbody(void) 82{ 83 struct proc *p = g_up_proc; 84 struct thread *tp = FIRST_THREAD_IN_PROC(p); 85 struct mtx mymutex; 86 87 mtx_init(&mymutex, "g_up", MTX_DEF, 0); 88 mtx_lock(&mymutex); 89 curthread->td_base_pri = PRIBIO; 90 for(;;) { 91 g_io_schedule_up(tp); 92 msleep(&g_wait_up, &mymutex, PRIBIO, "g_up", hz/10); 93 } 94} 95 96struct kproc_desc g_up_kp = { 97 "g_up", 98 g_up_procbody, 99 &g_up_proc, 100}; 101 102static struct proc *g_down_proc; 103 104static void 105g_down_procbody(void) 106{ 107 struct proc *p = g_down_proc; 108 struct thread *tp = FIRST_THREAD_IN_PROC(p); 109 struct mtx mymutex; 110 111 mtx_init(&mymutex, "g_down", MTX_DEF, 0); 112 mtx_lock(&mymutex); 113 curthread->td_base_pri = PRIBIO; 114 for(;;) { 115 g_io_schedule_down(tp); 116 msleep(&g_wait_down, &mymutex, PRIBIO, "g_down", hz/10); 117 } 118} 119 120struct kproc_desc g_down_kp = { 121 "g_down", 122 g_down_procbody, 123 &g_down_proc, 124}; 125 126static struct proc *g_event_proc; 127 128static void 129g_event_procbody(void) 130{ 131 132 curthread->td_base_pri = PRIBIO; 133 for(;;) { 134 g_run_events(); 135 tsleep(&g_wait_event, PRIBIO, "g_events", hz/10); 136 } 137} 138 139struct kproc_desc g_event_kp = { 140 "g_event", 141 g_event_procbody, 142 &g_event_proc, 143}; 144 145void 146g_init(void) 147{ 148 printf("Initializing GEOMetry subsystem\n"); 149 if (bootverbose) 150 g_debugflags |= G_T_TOPOLOGY; 151 sx_init(&topology_lock, "GEOM topology"); 152 g_io_init(); 153 g_event_init(); 154 mtx_lock(&Giant); 155 kproc_start(&g_event_kp); 156 kproc_start(&g_up_kp); 157 kproc_start(&g_down_kp); 158 mtx_unlock(&Giant); 159} 160 161static int 162sysctl_debug_geomdot(SYSCTL_HANDLER_ARGS) 163{ 164 int i, error; 165 struct sbuf *sb; 166 167 i = 0; 168 sb = g_confdot(); 169 error = sysctl_handle_opaque(oidp, sbuf_data(sb), sbuf_len(sb), req); 170 sbuf_delete(sb); 171 return (error); 172} 173 174SYSCTL_PROC(_debug, OID_AUTO, geomdot, CTLTYPE_STRING|CTLFLAG_RD, 175 0, 0, sysctl_debug_geomdot, "A", 176 "Dump the GEOM config"); 177 178static int 179sysctl_debug_geomconf(SYSCTL_HANDLER_ARGS) 180{ 181 int i, error; 182 struct sbuf *sb; 183 184 i = 0; 185 sb = g_conf(); 186 error = sysctl_handle_opaque(oidp, sbuf_data(sb), sbuf_len(sb), req); 187 sbuf_delete(sb); 188 return (error); 189} 190 191SYSCTL_PROC(_debug, OID_AUTO, geomconf, CTLTYPE_STRING|CTLFLAG_RD, 192 0, 0, sysctl_debug_geomconf, "A", 193 "Dump the GEOM config"); 194 195SYSCTL_INT(_debug, OID_AUTO, geomdebugflags, CTLTYPE_INT|CTLFLAG_RW, 196 &g_debugflags, 0, ""); 197 198SYSCTL_INT(_debug_sizeof, OID_AUTO, g_class, CTLTYPE_INT|CTLFLAG_RD, 199 0, sizeof(struct g_class), ""); 200SYSCTL_INT(_debug_sizeof, OID_AUTO, g_geom, CTLTYPE_INT|CTLFLAG_RD, 201 0, sizeof(struct g_geom), ""); 202SYSCTL_INT(_debug_sizeof, OID_AUTO, g_provider, CTLTYPE_INT|CTLFLAG_RD, 203 0, sizeof(struct g_provider), ""); 204SYSCTL_INT(_debug_sizeof, OID_AUTO, g_consumer, CTLTYPE_INT|CTLFLAG_RD, 205 0, sizeof(struct g_consumer), ""); 206SYSCTL_INT(_debug_sizeof, OID_AUTO, g_bioq, CTLTYPE_INT|CTLFLAG_RD, 207 0, sizeof(struct g_bioq), ""); 208SYSCTL_INT(_debug_sizeof, OID_AUTO, g_event, CTLTYPE_INT|CTLFLAG_RD, 209 0, sizeof(struct g_event), ""); 210