geom_kern.c revision 139451
161452Sdfr/*- 261452Sdfr * Copyright (c) 2002 Poul-Henning Kamp 361452Sdfr * Copyright (c) 2002 Networks Associates Technology, Inc. 461452Sdfr * All rights reserved. 561452Sdfr * 661452Sdfr * This software was developed for the FreeBSD Project by Poul-Henning Kamp 761452Sdfr * and NAI Labs, the Security Research Division of Network Associates, Inc. 861452Sdfr * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 961452Sdfr * DARPA CHATS research program. 1061452Sdfr * 1161452Sdfr * Redistribution and use in source and binary forms, with or without 1261452Sdfr * modification, are permitted provided that the following conditions 1361452Sdfr * are met: 1461452Sdfr * 1. Redistributions of source code must retain the above copyright 1561452Sdfr * notice, this list of conditions and the following disclaimer. 1661452Sdfr * 2. Redistributions in binary form must reproduce the above copyright 1761452Sdfr * notice, this list of conditions and the following disclaimer in the 1861452Sdfr * documentation and/or other materials provided with the distribution. 1961452Sdfr * 3. The names of the authors may not be used to endorse or promote 2061452Sdfr * products derived from this software without specific prior written 2161452Sdfr * permission. 2261452Sdfr * 2361452Sdfr * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 2461452Sdfr * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2561452Sdfr * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2661452Sdfr * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 2761452Sdfr * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2861452Sdfr * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2961452Sdfr * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 3061452Sdfr * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3161452Sdfr * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3261452Sdfr * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3361452Sdfr * SUCH DAMAGE. 3461452Sdfr */ 3561452Sdfr 3661452Sdfr#include <sys/cdefs.h> 3761452Sdfr__FBSDID("$FreeBSD: head/sys/geom/geom_kern.c 139451 2004-12-30 20:29:58Z jhb $"); 3876827Salfred 3979339Sjhb#include <sys/param.h> 4061452Sdfr#include <sys/systm.h> 4161452Sdfr#include <sys/kernel.h> 4261452Sdfr#include <sys/eventhandler.h> 4361452Sdfr#include <sys/malloc.h> 4461452Sdfr#include <sys/bio.h> 4561452Sdfr#include <sys/sysctl.h> 4661452Sdfr#include <sys/proc.h> 4761452Sdfr#include <sys/kthread.h> 4861452Sdfr#include <sys/lock.h> 4961452Sdfr#include <sys/mutex.h> 5061452Sdfr#include <sys/sbuf.h> 5161452Sdfr#include <sys/sched.h> 5261452Sdfr#include <sys/sx.h> 5361452Sdfr#include <geom/geom.h> 5461452Sdfr#include <geom/geom_int.h> 5561452Sdfr 5661452SdfrMALLOC_DEFINE(M_GEOM, "GEOM", "Geom data structures"); 5761452Sdfr 5861452Sdfrstruct sx topology_lock; 5961452Sdfr 6061452Sdfrstatic struct proc *g_up_proc; 6161452Sdfr 6261452Sdfrint g_debugflags; 6361452Sdfrint g_collectstats = 1; 6461452Sdfrint g_shutdown; 6561452Sdfr 6661452Sdfr/* 6761452Sdfr * G_UP and G_DOWN are the two threads which push I/O through the 6861452Sdfr * stack. 6961452Sdfr * 7061452Sdfr * Things are procesed in a FIFO order, but these threads could be 7161452Sdfr * part of I/O prioritization by deciding which bios/bioqs to service 7261452Sdfr * in what order. 7361452Sdfr * 7461452Sdfr * We have only one thread in each direction, it is belived that until 7561452Sdfr * a very non-trivial workload in the UP/DOWN path this will be enough, 7661452Sdfr * but more than one can actually be run without problems. 7761452Sdfr * 7861452Sdfr * Holding the "mymutex" is a debugging feature: It prevents people 7961452Sdfr * from sleeping in the UP/DOWN I/O path by mistake or design (doing 8061452Sdfr * so almost invariably result in deadlocks since it stalls all I/O 8161452Sdfr * processing in the given direction. 8261452Sdfr */ 8361452Sdfr 8461452Sdfrstatic void 8561452Sdfrg_up_procbody(void) 8661452Sdfr{ 8761452Sdfr struct proc *p = g_up_proc; 8861452Sdfr struct thread *tp = FIRST_THREAD_IN_PROC(p); 8961452Sdfr 9061452Sdfr mtx_assert(&Giant, MA_NOTOWNED); 9161452Sdfr mtx_lock_spin(&sched_lock); 9261452Sdfr sched_prio(tp, PRIBIO); 9361452Sdfr mtx_unlock_spin(&sched_lock); 9461452Sdfr for(;;) { 9561452Sdfr g_io_schedule_up(tp); 9661452Sdfr } 9761452Sdfr} 9861452Sdfr 9961452Sdfrstruct kproc_desc g_up_kp = { 10061452Sdfr "g_up", 10161452Sdfr g_up_procbody, 10261452Sdfr &g_up_proc, 10361452Sdfr}; 10461452Sdfr 10561452Sdfrstatic struct proc *g_down_proc; 10661452Sdfr 10761452Sdfrstatic void 10861452Sdfrg_down_procbody(void) 10961452Sdfr{ 11061452Sdfr struct proc *p = g_down_proc; 11161452Sdfr struct thread *tp = FIRST_THREAD_IN_PROC(p); 11261452Sdfr 11361452Sdfr mtx_assert(&Giant, MA_NOTOWNED); 11461452Sdfr mtx_lock_spin(&sched_lock); 11561452Sdfr sched_prio(tp, PRIBIO); 11661452Sdfr mtx_unlock_spin(&sched_lock); 11761452Sdfr for(;;) { 11861452Sdfr g_io_schedule_down(tp); 11961452Sdfr } 12061452Sdfr} 12161452Sdfr 12261452Sdfrstruct kproc_desc g_down_kp = { 12361452Sdfr "g_down", 12461452Sdfr g_down_procbody, 12561452Sdfr &g_down_proc, 12661452Sdfr}; 12761452Sdfr 12861452Sdfrstatic struct proc *g_event_proc; 12961452Sdfr 13061452Sdfrstatic void 13161452Sdfrg_event_procbody(void) 13261452Sdfr{ 13361452Sdfr struct proc *p = g_event_proc; 13461452Sdfr struct thread *tp = FIRST_THREAD_IN_PROC(p); 13561452Sdfr 13661452Sdfr mtx_assert(&Giant, MA_NOTOWNED); 13761452Sdfr mtx_lock_spin(&sched_lock); 13861452Sdfr sched_prio(tp, PRIBIO); 13961452Sdfr mtx_unlock_spin(&sched_lock); 14061452Sdfr for(;;) { 14161452Sdfr g_run_events(); 14261452Sdfr tsleep(&g_wait_event, PRIBIO, "-", hz/10); 14361452Sdfr } 14461452Sdfr} 14561452Sdfr 14661452Sdfrstatic struct kproc_desc g_event_kp = { 14761452Sdfr "g_event", 14861452Sdfr g_event_procbody, 14961452Sdfr &g_event_proc, 15061452Sdfr}; 15161452Sdfr 15261452Sdfrstatic void 15361452Sdfrgeom_shutdown(void *foo __unused) 15461452Sdfr{ 15561452Sdfr 15661452Sdfr g_shutdown = 1; 15761452Sdfr} 15861452Sdfr 15961452Sdfrvoid 16061452Sdfrg_init(void) 16161452Sdfr{ 16261452Sdfr 16361452Sdfr g_trace(G_T_TOPOLOGY, "g_ignition"); 16461452Sdfr sx_init(&topology_lock, "GEOM topology"); 16561452Sdfr g_io_init(); 16661452Sdfr g_event_init(); 16761452Sdfr g_ctl_init(); 16861452Sdfr mtx_lock(&Giant); 16961452Sdfr kproc_start(&g_event_kp); 17061452Sdfr kproc_start(&g_up_kp); 17161452Sdfr kproc_start(&g_down_kp); 17261452Sdfr mtx_unlock(&Giant); 17361452Sdfr EVENTHANDLER_REGISTER(shutdown_pre_sync, geom_shutdown, NULL, 17461452Sdfr SHUTDOWN_PRI_FIRST); 17561452Sdfr} 17661452Sdfr 17761452Sdfrstatic int 17861452Sdfrsysctl_kern_geom_conftxt(SYSCTL_HANDLER_ARGS) 17961452Sdfr{ 18061452Sdfr int error; 18161452Sdfr struct sbuf *sb; 18261452Sdfr 18361452Sdfr sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 18461452Sdfr g_waitfor_event(g_conftxt, sb, M_WAITOK, NULL); 18561452Sdfr error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1); 18661452Sdfr sbuf_delete(sb); 18761452Sdfr return error; 18861452Sdfr} 18961452Sdfr 19061452Sdfrstatic int 19161452Sdfrsysctl_kern_geom_confdot(SYSCTL_HANDLER_ARGS) 19261452Sdfr{ 19361452Sdfr int error; 19461452Sdfr struct sbuf *sb; 19561452Sdfr 19661452Sdfr sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 19761452Sdfr g_waitfor_event(g_confdot, sb, M_WAITOK, NULL); 19861452Sdfr error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1); 19961452Sdfr sbuf_delete(sb); 20061452Sdfr return error; 20161452Sdfr} 20261452Sdfr 20361452Sdfrstatic int 20461452Sdfrsysctl_kern_geom_confxml(SYSCTL_HANDLER_ARGS) 20561452Sdfr{ 20661452Sdfr int error; 20761452Sdfr struct sbuf *sb; 20861452Sdfr 20961452Sdfr sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 21061452Sdfr g_waitfor_event(g_confxml, sb, M_WAITOK, NULL); 21161452Sdfr error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1); 21261452Sdfr sbuf_delete(sb); 21361452Sdfr return error; 21461452Sdfr} 21561452Sdfr 21661452SdfrSYSCTL_NODE(_kern, OID_AUTO, geom, CTLFLAG_RW, 0, "GEOMetry management"); 21761452Sdfr 21861452SdfrSYSCTL_PROC(_kern_geom, OID_AUTO, confxml, CTLTYPE_STRING|CTLFLAG_RD, 21961452Sdfr 0, 0, sysctl_kern_geom_confxml, "", 22061452Sdfr "Dump the GEOM config in XML"); 22161452Sdfr 22261452SdfrSYSCTL_PROC(_kern_geom, OID_AUTO, confdot, CTLTYPE_STRING|CTLFLAG_RD, 22361452Sdfr 0, 0, sysctl_kern_geom_confdot, "", 22461452Sdfr "Dump the GEOM config in dot"); 22561452Sdfr 22661452SdfrSYSCTL_PROC(_kern_geom, OID_AUTO, conftxt, CTLTYPE_STRING|CTLFLAG_RD, 22761452Sdfr 0, 0, sysctl_kern_geom_conftxt, "", 22861452Sdfr "Dump the GEOM config in txt"); 22961452Sdfr 23061452SdfrTUNABLE_INT("kern.geom.debugflags", &g_debugflags); 23161452SdfrSYSCTL_INT(_kern_geom, OID_AUTO, debugflags, CTLFLAG_RW, 23261452Sdfr &g_debugflags, 0, ""); 23361452Sdfr 23461452SdfrSYSCTL_INT(_kern_geom, OID_AUTO, collectstats, CTLFLAG_RW, 23561452Sdfr &g_collectstats, 0, ""); 23661452Sdfr 23761452SdfrSYSCTL_INT(_debug_sizeof, OID_AUTO, g_class, CTLFLAG_RD, 23861452Sdfr 0, sizeof(struct g_class), ""); 23961452SdfrSYSCTL_INT(_debug_sizeof, OID_AUTO, g_geom, CTLFLAG_RD, 24061452Sdfr 0, sizeof(struct g_geom), ""); 24161452SdfrSYSCTL_INT(_debug_sizeof, OID_AUTO, g_provider, CTLFLAG_RD, 24261452Sdfr 0, sizeof(struct g_provider), ""); 24361452SdfrSYSCTL_INT(_debug_sizeof, OID_AUTO, g_consumer, CTLFLAG_RD, 24461452Sdfr 0, sizeof(struct g_consumer), ""); 24561452SdfrSYSCTL_INT(_debug_sizeof, OID_AUTO, g_bioq, CTLFLAG_RD, 24661452Sdfr 0, sizeof(struct g_bioq), ""); 24761452Sdfr