freebsd-dev/sys/kern/init_main.c
Julian Elischer dc9c271aa1 Changes to the LINUX_THREADS support to only allocate extra memory for
shared signal handling when there is shared signal handling being
used.

This removes the main objection to making the shared signal handling
a standard ability in rfork() and friends and 'unconditionalising'
this code. (i.e. the allocation of an extra 328 bytes per process).

Signal handling information remains in the U area until such a time as
it's reference count would be incremented to > 1. At that point a new
struct is malloc'd and maintained in KVM so that it can be shared between
the processes (threads) using it.

A function to check the reference count and move the struct back to the U
area when it drops back to 1 is also supplied. Signal information is
therefore now swapable for all processes that are not sharing that
information with other processes. THis should addres the concerns raised
by Garrett and others.

Submitted by:	"Richard Seaman, Jr." <dick@tar.com>
1999-01-07 21:23:50 +00:00

699 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
* $Id: init_main.c,v 1.102 1998/12/30 10:38:58 dfr Exp $
*/
#include "opt_devfs.h"
#include <sys/param.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/mount.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/sysent.h>
#include <sys/reboot.h>
#include <sys/sysproto.h>
#include <sys/vmmeter.h>
#include <sys/unistd.h>
#include <sys/malloc.h>
#include <machine/cpu.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_prot.h>
#include <sys/lock.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <sys/user.h>
#include <sys/copyright.h>
extern struct linker_set sysinit_set; /* XXX */
extern void __main __P((void));
extern void main __P((void *framep));
/* Components of the first process -- never freed. */
static struct session session0;
static struct pgrp pgrp0;
struct proc proc0;
static struct pcred cred0;
#ifdef COMPAT_LINUX_THREADS
static struct procsig procsig0;
#endif /* COMPAT_LINUX_THREADS */
static struct filedesc0 filedesc0;
static struct plimit limit0;
static struct vmspace vmspace0;
struct proc *initproc;
int cmask = CMASK;
extern struct user *proc0paddr;
struct vnode *rootvp;
int boothowto = 0; /* initialized so that it can be patched */
struct timeval boottime;
SYSCTL_STRUCT(_kern, KERN_BOOTTIME, boottime,
CTLFLAG_RD, &boottime, timeval, "");
static int shutdowntimeout = 120;
SYSCTL_INT(_kern, OID_AUTO, shutdown_timeout,
CTLFLAG_RW, &shutdowntimeout, 0, "");
/*
* Promiscuous argument pass for start_init()
*
* This is a kludge because we use a return from main() rather than a call
* to a new routine in locore.s to kick the kernel alive from locore.s.
*/
static void *init_framep;
#if __GNUC__ >= 2
void __main() {}
#endif
/*
* 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.
*/
struct sysinit **sysinit = (struct sysinit **)sysinit_set.ls_items;
struct sysinit **newsysinit;
/*
* 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(set)
struct sysinit **set;
{
struct sysinit **newset;
struct sysinit **sipp;
struct sysinit **xipp;
int count = 0;
if (newsysinit)
for (sipp = newsysinit; *sipp; sipp++)
count++;
else
for (sipp = sysinit; *sipp; sipp++)
count++;
for (sipp = set; *sipp; sipp++)
count++;
count++; /* Trailing NULL */
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; sipp++)
*xipp++ = *sipp;
else
for (sipp = sysinit; *sipp; sipp++)
*xipp++ = *sipp;
for (sipp = set; *sipp; sipp++)
*xipp++ = *sipp;
*xipp = NULL;
if (newsysinit)
free(newsysinit, M_TEMP);
newsysinit = newset;
}
/*
* 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
main(framep)
void *framep;
{
register struct sysinit **sipp; /* system initialization*/
register struct sysinit **xipp; /* interior loop of sort*/
register struct sysinit *save; /* bubble*/
/*
* Copy the locore.s frame pointer for proc0, this is forked into
* all other processes.
*/
init_framep = framep;
restart:
/*
* Perform a bubble sort of the system initialization objects by
* their subsystem (primary key) and order (secondary key).
*/
for (sipp = sysinit; *sipp; sipp++) {
for (xipp = sipp + 1; *xipp; 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; sipp++) {
if ((*sipp)->subsystem == SI_SUB_DUMMY)
continue; /* skip dummy task(s)*/
if ((*sipp)->subsystem == SI_SUB_DONE)
continue;
switch( (*sipp)->type) {
case SI_TYPE_DEFAULT:
/* no special processing*/
(*((*sipp)->func))((*sipp)->udata);
break;
case SI_TYPE_KTHREAD:
#if !defined(SMP)
/* kernel thread*/
if (fork1(&proc0, RFMEM|RFFDG|RFPROC))
panic("fork kernel thread");
cpu_set_fork_handler(pfind(proc0.p_retval[0]),
(*sipp)->func, (*sipp)->udata);
break;
#endif
case SI_TYPE_KPROCESS:
if (fork1(&proc0, RFFDG|RFPROC))
panic("fork kernel process");
cpu_set_fork_handler(pfind(proc0.p_retval[0]),
(*sipp)->func, (*sipp)->udata);
break;
default:
panic("init_main: unrecognized init type");
}
/* 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 != (struct sysinit **)sysinit_set.ls_items)
free(sysinit, M_TEMP);
sysinit = newsysinit;
newsysinit = NULL;
goto restart;
}
}
panic("Shouldn't get here!");
/* NOTREACHED*/
}
/*
* Start a kernel process. This is called after a fork() call in
* main() in the file kern/init_main.c.
*
* This function is used to start "internal" daemons.
*/
/* ARGSUSED*/
void
kproc_start(udata)
void *udata;
{
struct kproc_desc *kp = udata;
struct proc *p = curproc;
#ifdef DIAGNOSTIC
printf("Start pid=%d <%s>\n",p->p_pid, kp->arg0);
#endif
/* save a global descriptor, if desired*/
if( kp->global_procpp != NULL)
*kp->global_procpp = p;
/* this is a non-swapped system process*/
p->p_flag |= P_INMEM | P_SYSTEM;
/* set up arg0 for 'ps', et al*/
strcpy( p->p_comm, kp->arg0);
/* call the processes' main()...*/
(*kp->func)();
/* NOTREACHED */
panic("kproc_start: %s", kp->arg0);
}
/*
***************************************************************************
****
**** The following SYSINIT's belong elsewhere, but have not yet
**** been moved.
****
***************************************************************************
*/
#ifdef OMIT
/*
* Handled by vfs_mountroot (bad idea) at this time... should be
* done the same as 4.4Lite2.
*/
SYSINIT(swapinit, SI_SUB_SWAP, SI_ORDER_FIRST, swapinit, NULL)
#endif /* OMIT*/
static void print_caddr_t __P((void *data));
static void
print_caddr_t(data)
void *data;
{
printf("%s", (char *)data);
}
SYSINIT(announce, SI_SUB_COPYRIGHT, SI_ORDER_FIRST, print_caddr_t, copyright)
/*
***************************************************************************
****
**** The two following SYSINT'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 __P((void *dummy));
static void
proc0_init(dummy)
void *dummy;
{
register struct proc *p;
register struct filedesc0 *fdp;
register unsigned i;
/*
* Initialize the current process pointer (curproc) before
* any possible traps/probes to simplify trap processing.
*/
p = &proc0;
curproc = p; /* XXX redundant*/
/*
* Initialize process and pgrp structures.
*/
procinit();
/*
* Initialize sleep queue hash table
*/
sleepinit();
/*
* additional VM structures
*/
vm_init2();
/*
* Create process 0 (the swapper).
*/
LIST_INSERT_HEAD(&allproc, p, p_list);
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;
session0.s_count = 1;
session0.s_leader = p;
p->p_sysent = &aout_sysvec;
p->p_flag = P_INMEM | P_SYSTEM;
p->p_stat = SRUN;
p->p_nice = NZERO;
p->p_rtprio.type = RTP_PRIO_NORMAL;
p->p_rtprio.prio = 0;
/*
* Link for kernel based threads
*/
p->p_peers = 0;
p->p_leader = p;
bcopy("swapper", p->p_comm, sizeof ("swapper"));
/* Create credentials. */
cred0.p_refcnt = 1;
p->p_cred = &cred0;
p->p_ucred = crget();
p->p_ucred->cr_ngroups = 1; /* group 0 */
#ifdef COMPAT_LINUX_THREADS
/* Create procsig. */
p->p_procsig = &procsig0;
p->p_procsig->ps_refcnt = 2;
#endif /* COMPAT_LINUX_THREADS */
/* Create the file descriptor table. */
fdp = &filedesc0;
p->p_fd = &fdp->fd_fd;
fdp->fd_fd.fd_refcnt = 1;
fdp->fd_fd.fd_cmask = cmask;
fdp->fd_fd.fd_ofiles = fdp->fd_dfiles;
fdp->fd_fd.fd_ofileflags = fdp->fd_dfileflags;
fdp->fd_fd.fd_nfiles = NDFILE;
/* Create the limits structures. */
p->p_limit = &limit0;
for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++)
limit0.pl_rlimit[i].rlim_cur =
limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY;
limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur =
limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles;
limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur =
limit0.pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc;
i = ptoa(cnt.v_free_count);
limit0.pl_rlimit[RLIMIT_RSS].rlim_max = i;
limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = i;
limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = i / 3;
limit0.p_cpulimit = RLIM_INFINITY;
limit0.p_refcnt = 1;
/* Allocate a prototype map so we have something to fork. */
pmap_pinit0(&vmspace0.vm_pmap);
p->p_vmspace = &vmspace0;
vmspace0.vm_refcnt = 1;
vm_map_init(&vmspace0.vm_map, round_page(VM_MIN_ADDRESS),
trunc_page(VM_MAXUSER_ADDRESS));
vmspace0.vm_map.pmap = &vmspace0.vm_pmap;
p->p_addr = proc0paddr; /* XXX */
#ifndef __alpha__ /* XXX what is this? */
#define INCOMPAT_LITES2
#ifdef INCOMPAT_LITES2
/*
* proc0 needs to have a coherent frame base in its stack.
*/
cpu_set_init_frame(p, init_framep); /* XXX! */
#endif /* INCOMPAT_LITES2*/
#endif
/*
* We continue to place resource usage info and signal
* actions in the user struct so they're pageable.
*/
p->p_stats = &p->p_addr->u_stats;
p->p_sigacts = &p->p_addr->u_sigacts;
/*
* Charge root for one process.
*/
(void)chgproccnt(0, 1);
/*
* Initialize the procfs flags (to 0, of course)
*/
p->p_stops = p->p_stype = p->p_step = 0;
}
SYSINIT(p0init, SI_SUB_INTRINSIC, SI_ORDER_FIRST, proc0_init, NULL)
/* ARGSUSED*/
static void proc0_post __P((void *dummy));
static void
proc0_post(dummy)
void *dummy;
{
struct timespec ts;
/*
* Now can look at time, having had a chance to verify the time
* from the file system. Reset p->p_runtime as it may have been
* munched in mi_switch() after the time got set. Set
* p->p_switchtime to be consistent with this unmunching.
*/
microtime(&proc0.p_stats->p_start);
proc0.p_runtime = 0;
microuptime(&proc0.p_switchtime);
/*
* Give the ``random'' number generator a thump.
* XXX: Does read_random() contain enough bits to be used here ?
*/
nanotime(&ts);
srandom(ts.tv_sec ^ ts.tv_nsec);
/* Initialize signal state for process 0. */
siginit(&proc0);
}
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.
****
***************************************************************************
*/
/* ARGSUSED */
static void root_conf __P((void *dummy));
static void
root_conf(dummy)
void *dummy;
{
cpu_rootconf();
}
SYSINIT(root_conf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, root_conf, NULL)
/* ARGSUSED*/
static void xxx_vfs_root_fdtab __P((void *dummy));
static void
xxx_vfs_root_fdtab(dummy)
void *dummy;
{
register struct filedesc0 *fdp = &filedesc0;
/* Get the vnode for '/'. Set fdp->fd_fd.fd_cdir to reference it. */
if (VFS_ROOT(mountlist.cqh_first, &rootvnode))
panic("cannot find root vnode");
fdp->fd_fd.fd_cdir = rootvnode;
VREF(fdp->fd_fd.fd_cdir);
VOP_UNLOCK(rootvnode, 0, &proc0);
fdp->fd_fd.fd_rdir = rootvnode;
}
SYSINIT(retrofit, SI_SUB_ROOT_FDTAB, SI_ORDER_FIRST, xxx_vfs_root_fdtab, NULL)
/*
***************************************************************************
****
**** The following code probably belongs in another file, like
**** kern/init_init.c. It is here for two reasons only:
****
**** 1) This code returns to startup the system; this is
**** abnormal for a kernel thread.
**** 2) This code promiscuously uses init_frame
****
***************************************************************************
*/
static void kthread_init __P((void *dummy));
SYSINIT_KP(init,SI_SUB_KTHREAD_INIT, SI_ORDER_FIRST, kthread_init, NULL)
extern void prepare_usermode __P((void));
static void start_init __P((struct proc *p));
/* ARGSUSED*/
static void
kthread_init(dummy)
void *dummy;
{
/* Create process 1 (init(8)). */
start_init(curproc);
prepare_usermode();
/*
* This returns to the fork trampoline, then to user mode.
*/
return;
}
/*
* List of paths to try when searching for "init".
*/
static char *initpaths[] = {
"/sbin/init",
"/sbin/oinit",
"/sbin/init.bak",
"/stand/sysinstall",
NULL,
};
/*
* Start the initial user process; try exec'ing each pathname in "initpaths".
* The program is invoked with one argument containing the boot flags.
*/
static void
start_init(p)
struct proc *p;
{
vm_offset_t addr;
struct execve_args args;
int options, i, error;
char **pathp, *path, *ucp, **uap, *arg0, *arg1;
initproc = p;
/*
* Need just enough stack to hold the faked-up "execve()" arguments.
*/
addr = trunc_page(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;
for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) {
/*
* Move out the boot flag argument.
*/
options = 0;
ucp = (char *)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).
*/
for (i = strlen(path) + 1; i >= 0; i--)
(void)subyte(--ucp, path[i]);
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 to main() which returns to btext
* which completes the system startup.
*/
if ((error = execve(p, &args)) == 0)
return;
if (error != ENOENT)
printf("exec %s: error %d\n", path, error);
}
printf("init: not found\n");
panic("no init");
}