usr/src/sys/kern/init_main.c

/*
 * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 *      @(#)init_main.c 7.12 (Berkeley) %G%
 */

#include "param.h"
#include "systm.h"
#include "user.h"
#include "kernel.h"
#include "mount.h"
#include "map.h"
#include "proc.h"
#include "vnode.h"
#include "seg.h"
#include "conf.h"
#include "buf.h"
#include "vm.h"
#include "cmap.h"
#include "text.h"
#include "clist.h"
#include "malloc.h"
#include "protosw.h"
#include "reboot.h"

#include "machine/pte.h"
#include "machine/reg.h"
#include "machine/cpu.h"

int     cmask = CMASK;
extern  int (*mountroot)();
/*
 * Initialization code.
 * Called from cold start routine as
 * soon as a stack and segmentation
 * have been established.
 * Functions:
 *      clear and free user core
 *      turn on clock
 *      hand craft 0th process
 *      call all initialization routines
 *      fork - process 0 to schedule
 *           - process 1 execute bootstrap
 *           - process 2 to page out
 */
main(firstaddr)
        int firstaddr;
{
        register int i;
        register struct proc *p;
        register struct pgrp *pg;
        int s;

        rqinit();
#include "loop.h"
        startup(firstaddr);

        /*
         * set up system process 0 (swapper)
         */
        p = &proc[0];
        p->p_p0br = u.u_pcb.pcb_p0br;
        p->p_szpt = 1;
        p->p_addr = uaddr(p);
        p->p_stat = SRUN;
        p->p_flag |= SLOAD|SSYS;
        p->p_nice = NZERO;
        setredzone(p->p_addr, (caddr_t)&u);
        u.u_procp = p;
        MALLOC(pgrphash[0], struct pgrp *, sizeof (struct pgrp),
                M_PGRP, M_NOWAIT);
        if ((pg = pgrphash[0]) == NULL)
                panic("no space to craft zero'th process group");
        pg->pg_id = 0;
        pg->pg_hforw = 0;
        pg->pg_mem = p;
        pg->pg_jobc = 0;
        p->p_pgrp = pg;
        p->p_pgrpnxt = 0;
        MALLOC(pg->pg_session, struct session *, sizeof (struct session),
                M_SESSION, M_NOWAIT);
        if (pg->pg_session == NULL)
                panic("no space to craft zero'th session");
        pg->pg_session->s_count = 1;
        pg->pg_session->s_leader = 0;
#ifdef KTRACE
        p->p_tracep = NULL;
        p->p_traceflag = 0;
#endif
        /*
         * These assume that the u. area is always mapped
         * to the same virtual address. Otherwise must be
         * handled when copying the u. area in newproc().
         */
        u.u_nd.ni_iov = &u.u_nd.ni_nd.nd_iovec;
        u.u_nd.ni_iovcnt = 1;
        u.u_nd.ni_base = (caddr_t)&u.u_nd.ni_dent;
        u.u_nd.ni_rw = UIO_WRITE;
        u.u_nd.ni_segflg = UIO_SYSSPACE;
        u.u_ap = u.u_arg;

        u.u_cmask = cmask;
        u.u_lastfile = -1;
        for (i = 0; i < sizeof(u.u_rlimit)/sizeof(u.u_rlimit[0]); i++)
                u.u_rlimit[i].rlim_cur = u.u_rlimit[i].rlim_max =
                    RLIM_INFINITY;
        /*
         * configure virtual memory system,
         * set vm rlimits
         */
        vminit();

        /*
         * Get vnodes for swapdev, argdev, and rootdev.
         */
        ihinit();
        nchinit();
        if (bdevvp(swapdev, &swapdev_vp) ||
            bdevvp(argdev, &argdev_vp) ||
            bdevvp(rootdev, &rootvp))
                panic("can't setup bdevvp's");

        /*
         * Setup credentials
         */
        u.u_cred = crget();
        u.u_ngroups = 1;

#if defined(QUOTA)
        qtinit();
        p->p_quota = u.u_quota = getquota(0, 0, Q_NDQ);
#endif
        startrtclock();
#if defined(vax)
#include "kg.h"
#if NKG > 0
        startkgclock();
#endif
#endif

        /*
         * Initialize tables, protocols, and set up well-known inodes.
         */
        mbinit();
        cinit();
#include "sl.h"
#if NSL > 0
        slattach();                     /* XXX */
#endif
#if NLOOP > 0
        loattach();                     /* XXX */
#endif
        /*
         * Block reception of incoming packets
         * until protocols have been initialized.
         */
        s = splimp();
        ifinit();
        domaininit();
        splx(s);
        pqinit();
        xinit();
        swapinit();
#ifdef GPROF
        kmstartup();
#endif
#ifdef NFS
        nfsinit();
#endif

/* kick off timeout driven events by calling first time */
        roundrobin();
        schedcpu();
        schedpaging();

/* set up the root file system */
        if ((*mountroot)())
                panic("cannot mount root");
        /*
         * Get vnode for '/'.
         * Setup rootdir and u.u_cdir to point to it.
         */
        if (VFS_ROOT(rootfs, &rootdir))
                panic("cannot find root vnode");
        u.u_cdir = rootdir;
        u.u_cdir->v_count++;
        VOP_UNLOCK(rootdir);
        u.u_rdir = NULL;
        boottime = time;

        u.u_dmap = zdmap;
        u.u_smap = zdmap;

        enablertclock();                /* enable realtime clock interrupts */
        /*
         * make init process
         */

        proc[0].p_szpt = CLSIZE;
        if (newproc(0)) {
                expand(clrnd((int)btoc(szicode)), 0);
                (void) swpexpand(u.u_dsize, (size_t)0, &u.u_dmap, &u.u_smap);
                (void) copyout((caddr_t)icode, (caddr_t)0, (unsigned)szicode);
                /*
                 * Return goes to loc. 0 of user init
                 * code just copied out.
                 */
                return;
        }
        /*
         * make page-out daemon (process 2)
         * the daemon has ctopt(nswbuf*CLSIZE*KLMAX) pages of page
         * table so that it can map dirty pages into
         * its address space during asychronous pushes.
         */
        proc[0].p_szpt = clrnd(ctopt(nswbuf*CLSIZE*KLMAX + UPAGES));
        if (newproc(0)) {
                proc[2].p_flag |= SLOAD|SSYS;
                proc[2].p_dsize = u.u_dsize = nswbuf*CLSIZE*KLMAX;
                pageout();
                /*NOTREACHED*/
        }

        /*
         * enter scheduling loop
         */
        proc[0].p_szpt = 1;
        sched();
}

/*
 * Initialize hash links for buffers.
 */
bhinit()
{
        register int i;
        register struct bufhd *bp;

        for (bp = bufhash, i = 0; i < BUFHSZ; i++, bp++)
                bp->b_forw = bp->b_back = (struct buf *)bp;
}

/*
 * Initialize the buffer I/O system by freeing
 * all buffers and setting all device buffer lists to empty.
 */
binit()
{
        register struct buf *bp, *dp;
        register int i;
        int base, residual;

        for (dp = bfreelist; dp < &bfreelist[BQUEUES]; dp++) {
                dp->b_forw = dp->b_back = dp->av_forw = dp->av_back = dp;
                dp->b_flags = B_HEAD;
        }
        base = bufpages / nbuf;
        residual = bufpages % nbuf;
        for (i = 0; i < nbuf; i++) {
                bp = &buf[i];
                bp->b_dev = NODEV;
                bp->b_bcount = 0;
                bp->b_un.b_addr = buffers + i * MAXBSIZE;
                if (i < residual)
                        bp->b_bufsize = (base + 1) * CLBYTES;
                else
                        bp->b_bufsize = base * CLBYTES;
                binshash(bp, &bfreelist[BQ_AGE]);
                bp->b_flags = B_BUSY|B_INVAL;
                brelse(bp);
        }
}

/*
 * Set up swap devices.
 * Initialize linked list of free swap
 * headers. These do not actually point
 * to buffers, but rather to pages that
 * are being swapped in and out.
 */
swapinit()
{
        register int i;
        register struct buf *sp = swbuf;
        struct swdevt *swp;
        int error;

        /*
         * Count swap devices, and adjust total swap space available.
         * Some of this space will not be available until a swapon()
         * system is issued, usually when the system goes multi-user.
         */
        nswdev = 0;
        nswap = 0;
        for (swp = swdevt; swp->sw_dev; swp++) {
                nswdev++;
                if (swp->sw_nblks > nswap)
                        nswap = swp->sw_nblks;
        }
        if (nswdev == 0)
                panic("swapinit");
        if (nswdev > 1)
                nswap = ((nswap + dmmax - 1) / dmmax) * dmmax;
        nswap *= nswdev;
        /*
         * If there are multiple swap areas,
         * allow more paging operations per second.
         */
        if (nswdev > 1)
                maxpgio = (maxpgio * (2 * nswdev - 1)) / 2;
        if (bdevvp(swdevt[0].sw_dev, &swdevt[0].sw_vp))
                panic("swapvp");
        if (error = swfree(0)) {
                printf("swfree errno %d\n", error);     /* XXX */
                panic("swapinit swfree 0");
        }

        /*
         * Now set up swap buffer headers.
         */
        bswlist.av_forw = sp;
        for (i=0; i<nswbuf-1; i++, sp++)
                sp->av_forw = sp+1;
        sp->av_forw = NULL;
}

/*
 * Initialize clist by freeing all character blocks, then count
 * number of character devices. (Once-only routine)
 */
cinit()
{
        register int ccp;
        register struct cblock *cp;

        ccp = (int)cfree;
        ccp = (ccp+CROUND) & ~CROUND;
        for(cp=(struct cblock *)ccp; cp < &cfree[nclist-1]; cp++) {
                cp->c_next = cfreelist;
                cfreelist = cp;
                cfreecount += CBSIZE;
        }
}