1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-24 11:29:10 +00:00
freebsd/sys/kern/init_main.c
Suleiman Souhlal 571dcd15e2 Fix the recent panics/LORs/hangs created by my kqueue commit by:
- Introducing the possibility of using locks different than mutexes
for the knlist locking. In order to do this, we add three arguments to
knlist_init() to specify the functions to use to lock, unlock and
check if the lock is owned. If these arguments are NULL, we assume
mtx_lock, mtx_unlock and mtx_owned, respectively.

- Using the vnode lock for the knlist locking, when doing kqueue operations
on a vnode. This way, we don't have to lock the vnode while holding a
mutex, in filt_vfsread.

Reviewed by:	jmg
Approved by:	re (scottl), scottl (mentor override)
Pointyhat to:	ssouhlal
Will be happy:	everyone
2005-07-01 16:28:32 +00:00

676 lines
18 KiB
C

/*-
* Copyright (c) 1995 Terrence R. Lambert
* All rights reserved.
*
* Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)init_main.c 8.9 (Berkeley) 1/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_init_path.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/exec.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/mac.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/systm.h>
#include <sys/signalvar.h>
#include <sys/vnode.h>
#include <sys/sysent.h>
#include <sys/reboot.h>
#include <sys/sched.h>
#include <sys/sx.h>
#include <sys/sysproto.h>
#include <sys/vmmeter.h>
#include <sys/unistd.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <machine/cpu.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <sys/copyright.h>
void mi_startup(void); /* Should be elsewhere */
/* Components of the first process -- never freed. */
static struct session session0;
static struct pgrp pgrp0;
struct proc proc0;
struct thread thread0;
struct ksegrp ksegrp0;
struct vmspace vmspace0;
struct proc *initproc;
int boothowto = 0; /* initialized so that it can be patched */
SYSCTL_INT(_debug, OID_AUTO, boothowto, CTLFLAG_RD, &boothowto, 0, "");
int bootverbose;
SYSCTL_INT(_debug, OID_AUTO, bootverbose, CTLFLAG_RW, &bootverbose, 0, "");
/*
* This ensures that there is at least one entry so that the sysinit_set
* symbol is not undefined. A sybsystem ID of SI_SUB_DUMMY is never
* executed.
*/
SYSINIT(placeholder, SI_SUB_DUMMY, SI_ORDER_ANY, NULL, NULL)
/*
* The sysinit table itself. Items are checked off as the are run.
* If we want to register new sysinit types, add them to newsysinit.
*/
SET_DECLARE(sysinit_set, struct sysinit);
struct sysinit **sysinit, **sysinit_end;
struct sysinit **newsysinit, **newsysinit_end;
/*
* Merge a new sysinit set into the current set, reallocating it if
* necessary. This can only be called after malloc is running.
*/
void
sysinit_add(struct sysinit **set, struct sysinit **set_end)
{
struct sysinit **newset;
struct sysinit **sipp;
struct sysinit **xipp;
int count;
count = set_end - set;
if (newsysinit)
count += newsysinit_end - newsysinit;
else
count += sysinit_end - sysinit;
newset = malloc(count * sizeof(*sipp), M_TEMP, M_NOWAIT);
if (newset == NULL)
panic("cannot malloc for sysinit");
xipp = newset;
if (newsysinit)
for (sipp = newsysinit; sipp < newsysinit_end; sipp++)
*xipp++ = *sipp;
else
for (sipp = sysinit; sipp < sysinit_end; sipp++)
*xipp++ = *sipp;
for (sipp = set; sipp < set_end; sipp++)
*xipp++ = *sipp;
if (newsysinit)
free(newsysinit, M_TEMP);
newsysinit = newset;
newsysinit_end = newset + count;
}
/*
* System startup; initialize the world, create process 0, mount root
* filesystem, and fork to create init and pagedaemon. Most of the
* hard work is done in the lower-level initialization routines including
* startup(), which does memory initialization and autoconfiguration.
*
* This allows simple addition of new kernel subsystems that require
* boot time initialization. It also allows substitution of subsystem
* (for instance, a scheduler, kernel profiler, or VM system) by object
* module. Finally, it allows for optional "kernel threads".
*/
void
mi_startup(void)
{
register struct sysinit **sipp; /* system initialization*/
register struct sysinit **xipp; /* interior loop of sort*/
register struct sysinit *save; /* bubble*/
if (sysinit == NULL) {
sysinit = SET_BEGIN(sysinit_set);
sysinit_end = SET_LIMIT(sysinit_set);
}
restart:
/*
* Perform a bubble sort of the system initialization objects by
* their subsystem (primary key) and order (secondary key).
*/
for (sipp = sysinit; sipp < sysinit_end; sipp++) {
for (xipp = sipp + 1; xipp < sysinit_end; xipp++) {
if ((*sipp)->subsystem < (*xipp)->subsystem ||
((*sipp)->subsystem == (*xipp)->subsystem &&
(*sipp)->order <= (*xipp)->order))
continue; /* skip*/
save = *sipp;
*sipp = *xipp;
*xipp = save;
}
}
/*
* Traverse the (now) ordered list of system initialization tasks.
* Perform each task, and continue on to the next task.
*
* The last item on the list is expected to be the scheduler,
* which will not return.
*/
for (sipp = sysinit; sipp < sysinit_end; sipp++) {
if ((*sipp)->subsystem == SI_SUB_DUMMY)
continue; /* skip dummy task(s)*/
if ((*sipp)->subsystem == SI_SUB_DONE)
continue;
/* Call function */
(*((*sipp)->func))((*sipp)->udata);
/* Check off the one we're just done */
(*sipp)->subsystem = SI_SUB_DONE;
/* Check if we've installed more sysinit items via KLD */
if (newsysinit != NULL) {
if (sysinit != SET_BEGIN(sysinit_set))
free(sysinit, M_TEMP);
sysinit = newsysinit;
sysinit_end = newsysinit_end;
newsysinit = NULL;
newsysinit_end = NULL;
goto restart;
}
}
panic("Shouldn't get here!");
/* NOTREACHED*/
}
/*
***************************************************************************
****
**** The following SYSINIT's belong elsewhere, but have not yet
**** been moved.
****
***************************************************************************
*/
static void
print_caddr_t(void *data __unused)
{
printf("%s", (char *)data);
}
SYSINIT(announce, SI_SUB_COPYRIGHT, SI_ORDER_FIRST, print_caddr_t, copyright)
SYSINIT(version, SI_SUB_COPYRIGHT, SI_ORDER_SECOND, print_caddr_t, version)
#ifdef WITNESS
static char wit_warn[] =
"WARNING: WITNESS option enabled, expect reduced performance.\n";
SYSINIT(witwarn, SI_SUB_COPYRIGHT, SI_ORDER_SECOND + 1,
print_caddr_t, wit_warn)
#endif
#ifdef DIAGNOSTIC
static char diag_warn[] =
"WARNING: DIAGNOSTIC option enabled, expect reduced performance.\n";
SYSINIT(diagwarn, SI_SUB_COPYRIGHT, SI_ORDER_SECOND + 2,
print_caddr_t, diag_warn)
#endif
static void
set_boot_verbose(void *data __unused)
{
if (boothowto & RB_VERBOSE)
bootverbose++;
}
SYSINIT(boot_verbose, SI_SUB_TUNABLES, SI_ORDER_ANY, set_boot_verbose, NULL)
struct sysentvec null_sysvec = {
0,
NULL,
0,
0,
NULL,
0,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
NULL,
"null",
NULL,
NULL,
0,
PAGE_SIZE,
VM_MIN_ADDRESS,
VM_MAXUSER_ADDRESS,
USRSTACK,
PS_STRINGS,
VM_PROT_ALL,
NULL,
NULL,
NULL
};
/*
***************************************************************************
****
**** The two following SYSINIT's are proc0 specific glue code. I am not
**** convinced that they can not be safely combined, but their order of
**** operation has been maintained as the same as the original init_main.c
**** for right now.
****
**** These probably belong in init_proc.c or kern_proc.c, since they
**** deal with proc0 (the fork template process).
****
***************************************************************************
*/
/* ARGSUSED*/
static void
proc0_init(void *dummy __unused)
{
struct proc *p;
unsigned i;
struct thread *td;
struct ksegrp *kg;
GIANT_REQUIRED;
p = &proc0;
td = &thread0;
kg = &ksegrp0;
/*
* Initialize magic number.
*/
p->p_magic = P_MAGIC;
/*
* Initialize thread, process and ksegrp structures.
*/
procinit(); /* set up proc zone */
threadinit(); /* set up thead, upcall and KSEGRP zones */
/*
* Initialise scheduler resources.
* Add scheduler specific parts to proc, ksegrp, thread as needed.
*/
schedinit(); /* scheduler gets its house in order */
/*
* Initialize sleep queue hash table
*/
sleepinit();
/*
* additional VM structures
*/
vm_init2();
/*
* Create process 0 (the swapper).
*/
LIST_INSERT_HEAD(&allproc, p, p_list);
LIST_INSERT_HEAD(PIDHASH(0), p, p_hash);
mtx_init(&pgrp0.pg_mtx, "process group", NULL, MTX_DEF | MTX_DUPOK);
p->p_pgrp = &pgrp0;
LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
LIST_INIT(&pgrp0.pg_members);
LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist);
pgrp0.pg_session = &session0;
mtx_init(&session0.s_mtx, "session", NULL, MTX_DEF);
session0.s_count = 1;
session0.s_leader = p;
p->p_sysent = &null_sysvec;
p->p_flag = P_SYSTEM;
p->p_sflag = PS_INMEM;
p->p_state = PRS_NORMAL;
knlist_init(&p->p_klist, &p->p_mtx, NULL, NULL, NULL);
p->p_nice = NZERO;
td->td_state = TDS_RUNNING;
kg->kg_pri_class = PRI_TIMESHARE;
kg->kg_user_pri = PUSER;
td->td_priority = PVM;
td->td_base_pri = PUSER;
td->td_oncpu = 0;
p->p_peers = 0;
p->p_leader = p;
bcopy("swapper", p->p_comm, sizeof ("swapper"));
callout_init(&p->p_itcallout, CALLOUT_MPSAFE);
callout_init(&td->td_slpcallout, CALLOUT_MPSAFE);
/* Create credentials. */
p->p_ucred = crget();
p->p_ucred->cr_ngroups = 1; /* group 0 */
p->p_ucred->cr_uidinfo = uifind(0);
p->p_ucred->cr_ruidinfo = uifind(0);
p->p_ucred->cr_prison = NULL; /* Don't jail it. */
#ifdef MAC
mac_create_proc0(p->p_ucred);
#endif
td->td_ucred = crhold(p->p_ucred);
/* Create sigacts. */
p->p_sigacts = sigacts_alloc();
/* Initialize signal state for process 0. */
siginit(&proc0);
/* Create the file descriptor table. */
p->p_fd = fdinit(NULL);
p->p_fdtol = NULL;
/* Create the limits structures. */
p->p_limit = lim_alloc();
for (i = 0; i < RLIM_NLIMITS; i++)
p->p_limit->pl_rlimit[i].rlim_cur =
p->p_limit->pl_rlimit[i].rlim_max = RLIM_INFINITY;
p->p_limit->pl_rlimit[RLIMIT_NOFILE].rlim_cur =
p->p_limit->pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles;
p->p_limit->pl_rlimit[RLIMIT_NPROC].rlim_cur =
p->p_limit->pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc;
i = ptoa(cnt.v_free_count);
p->p_limit->pl_rlimit[RLIMIT_RSS].rlim_max = i;
p->p_limit->pl_rlimit[RLIMIT_MEMLOCK].rlim_max = i;
p->p_limit->pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = i / 3;
p->p_cpulimit = RLIM_INFINITY;
p->p_stats = pstats_alloc();
/* Allocate a prototype map so we have something to fork. */
pmap_pinit0(vmspace_pmap(&vmspace0));
p->p_vmspace = &vmspace0;
vmspace0.vm_refcnt = 1;
vm_map_init(&vmspace0.vm_map, p->p_sysent->sv_minuser,
p->p_sysent->sv_maxuser);
vmspace0.vm_map.pmap = vmspace_pmap(&vmspace0);
/*
* Charge root for one process.
*/
(void)chgproccnt(p->p_ucred->cr_ruidinfo, 1, 0);
}
SYSINIT(p0init, SI_SUB_INTRINSIC, SI_ORDER_FIRST, proc0_init, NULL)
/* ARGSUSED*/
static void
proc0_post(void *dummy __unused)
{
struct timespec ts;
struct proc *p;
/*
* Now we can look at the time, having had a chance to verify the
* time from the filesystem. Pretend that proc0 started now.
*/
sx_slock(&allproc_lock);
LIST_FOREACH(p, &allproc, p_list) {
microuptime(&p->p_stats->p_start);
p->p_rux.rux_runtime.sec = 0;
p->p_rux.rux_runtime.frac = 0;
}
sx_sunlock(&allproc_lock);
binuptime(PCPU_PTR(switchtime));
PCPU_SET(switchticks, ticks);
/*
* Give the ``random'' number generator a thump.
*/
nanotime(&ts);
srandom(ts.tv_sec ^ ts.tv_nsec);
}
SYSINIT(p0post, SI_SUB_INTRINSIC_POST, SI_ORDER_FIRST, proc0_post, NULL)
/*
***************************************************************************
****
**** The following SYSINIT's and glue code should be moved to the
**** respective files on a per subsystem basis.
****
***************************************************************************
*/
/*
***************************************************************************
****
**** The following code probably belongs in another file, like
**** kern/init_init.c.
****
***************************************************************************
*/
/*
* List of paths to try when searching for "init".
*/
static char init_path[MAXPATHLEN] =
#ifdef INIT_PATH
__XSTRING(INIT_PATH);
#else
"/sbin/init:/sbin/oinit:/sbin/init.bak:/rescue/init:/stand/sysinstall";
#endif
SYSCTL_STRING(_kern, OID_AUTO, init_path, CTLFLAG_RD, init_path, 0,
"Path used to search the init process");
/*
* Start the initial user process; try exec'ing each pathname in init_path.
* The program is invoked with one argument containing the boot flags.
*/
static void
start_init(void *dummy)
{
vm_offset_t addr;
struct execve_args args;
int options, error;
char *var, *path, *next, *s;
char *ucp, **uap, *arg0, *arg1;
struct thread *td;
struct proc *p;
mtx_lock(&Giant);
GIANT_REQUIRED;
td = curthread;
p = td->td_proc;
vfs_mountroot();
#ifdef MAC
mac_create_root_mount(td->td_ucred, TAILQ_FIRST(&mountlist));
#endif
/*
* Need just enough stack to hold the faked-up "execve()" arguments.
*/
addr = p->p_sysent->sv_usrstack - PAGE_SIZE;
if (vm_map_find(&p->p_vmspace->vm_map, NULL, 0, &addr, PAGE_SIZE,
FALSE, VM_PROT_ALL, VM_PROT_ALL, 0) != 0)
panic("init: couldn't allocate argument space");
p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
p->p_vmspace->vm_ssize = 1;
if ((var = getenv("init_path")) != NULL) {
strlcpy(init_path, var, sizeof(init_path));
freeenv(var);
}
for (path = init_path; *path != '\0'; path = next) {
while (*path == ':')
path++;
if (*path == '\0')
break;
for (next = path; *next != '\0' && *next != ':'; next++)
/* nothing */ ;
if (bootverbose)
printf("start_init: trying %.*s\n", (int)(next - path),
path);
/*
* Move out the boot flag argument.
*/
options = 0;
ucp = (char *)p->p_sysent->sv_usrstack;
(void)subyte(--ucp, 0); /* trailing zero */
if (boothowto & RB_SINGLE) {
(void)subyte(--ucp, 's');
options = 1;
}
#ifdef notyet
if (boothowto & RB_FASTBOOT) {
(void)subyte(--ucp, 'f');
options = 1;
}
#endif
#ifdef BOOTCDROM
(void)subyte(--ucp, 'C');
options = 1;
#endif
if (options == 0)
(void)subyte(--ucp, '-');
(void)subyte(--ucp, '-'); /* leading hyphen */
arg1 = ucp;
/*
* Move out the file name (also arg 0).
*/
(void)subyte(--ucp, 0);
for (s = next - 1; s >= path; s--)
(void)subyte(--ucp, *s);
arg0 = ucp;
/*
* Move out the arg pointers.
*/
uap = (char **)((intptr_t)ucp & ~(sizeof(intptr_t)-1));
(void)suword((caddr_t)--uap, (long)0); /* terminator */
(void)suword((caddr_t)--uap, (long)(intptr_t)arg1);
(void)suword((caddr_t)--uap, (long)(intptr_t)arg0);
/*
* Point at the arguments.
*/
args.fname = arg0;
args.argv = uap;
args.envv = NULL;
/*
* Now try to exec the program. If can't for any reason
* other than it doesn't exist, complain.
*
* Otherwise, return via fork_trampoline() all the way
* to user mode as init!
*/
if ((error = execve(td, &args)) == 0) {
mtx_unlock(&Giant);
return;
}
if (error != ENOENT)
printf("exec %.*s: error %d\n", (int)(next - path),
path, error);
}
printf("init: not found in path %s\n", init_path);
panic("no init");
}
/*
* Like kthread_create(), but runs in it's own address space.
* We do this early to reserve pid 1.
*
* Note special case - do not make it runnable yet. Other work
* in progress will change this more.
*/
static void
create_init(const void *udata __unused)
{
struct ucred *newcred, *oldcred;
int error;
error = fork1(&thread0, RFFDG | RFPROC | RFSTOPPED, 0, &initproc);
if (error)
panic("cannot fork init: %d\n", error);
KASSERT(initproc->p_pid == 1, ("create_init: initproc->p_pid != 1"));
/* divorce init's credentials from the kernel's */
newcred = crget();
PROC_LOCK(initproc);
initproc->p_flag |= P_SYSTEM;
oldcred = initproc->p_ucred;
crcopy(newcred, oldcred);
#ifdef MAC
mac_create_proc1(newcred);
#endif
initproc->p_ucred = newcred;
PROC_UNLOCK(initproc);
crfree(oldcred);
cred_update_thread(FIRST_THREAD_IN_PROC(initproc));
mtx_lock_spin(&sched_lock);
initproc->p_sflag |= PS_INMEM;
mtx_unlock_spin(&sched_lock);
cpu_set_fork_handler(FIRST_THREAD_IN_PROC(initproc), start_init, NULL);
}
SYSINIT(init, SI_SUB_CREATE_INIT, SI_ORDER_FIRST, create_init, NULL)
/*
* Make it runnable now.
*/
static void
kick_init(const void *udata __unused)
{
struct thread *td;
td = FIRST_THREAD_IN_PROC(initproc);
mtx_lock_spin(&sched_lock);
TD_SET_CAN_RUN(td);
setrunqueue(td, SRQ_BORING); /* XXXKSE */
mtx_unlock_spin(&sched_lock);
}
SYSINIT(kickinit, SI_SUB_KTHREAD_INIT, SI_ORDER_FIRST, kick_init, NULL)