usr/src/usr.sbin/amd/amd/nfs_start.c

/*
 * $Id: nfs_start.c,v 5.2.1.2 90/12/21 16:41:40 jsp Alpha $
 *
 * Copyright (c) 1990 Jan-Simon Pendry
 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Jan-Simon Pendry at Imperial College, London.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)nfs_start.c 5.2 (Berkeley) %G%
 */

#include "am.h"
#include "amq.h"
#include <sys/signal.h>
#include <setjmp.h>
extern jmp_buf select_intr;
extern int select_intr_valid;

#ifdef HAS_TFS
/*
 * Use replacement for RPC/UDP transport
 * so that we do NFS gatewaying.
 */
#define svcudp_create svcudp2_create
extern SVCXPRT *svcudp2_create P((int));
#endif /* HAS_TFS */

extern void nfs_program_2();
extern void amq_program_1();

unsigned short nfs_port;
SVCXPRT *nfsxprt;

extern int fwd_sock;
int max_fds = -1;

#define MASKED_SIGS     (sigmask(SIGINT)|sigmask(SIGTERM)|sigmask(SIGCHLD)|sigmask(SIGHUP))

#ifdef DEBUG
/*
 * Check that we are not burning resources
 */
static void checkup(P_void)
{

static int max_fd = 0;
static char *max_mem = 0;

        int next_fd = dup(0);
        extern caddr_t sbrk P((int));
        caddr_t next_mem = sbrk(0);
        close(next_fd);

        /*if (max_fd < 0) {
                max_fd = next_fd;
        } else*/ if (max_fd < next_fd) {
                dlog("%d new fds allocated; total is %d",
                        next_fd - max_fd, next_fd);
                max_fd = next_fd;
        }

        /*if (max_mem == 0) {
                max_mem = next_mem;
        } else*/ if (max_mem < next_mem) {
                dlog("%#x bytes of memory allocated; total is %#x (%d pages)",
                        next_mem - max_mem,
                        next_mem,
                        ((int)next_mem+getpagesize()-1)/getpagesize());
                max_mem = next_mem;
        }
}
#endif /* DEBUG */

static int do_select(smask, fds, fdp, tvp)
int smask;
int fds;
int *fdp;
struct timeval *tvp;
{
        int sig;
        int nsel;
        if (sig = setjmp(select_intr)) {
                select_intr_valid = 0;
                /* Got a signal */
                switch (sig) {
                case SIGINT:
                case SIGTERM:
                        amd_state = Finishing;
                        reschedule_timeout_mp();
                        break;
                }
                nsel = -1;
                errno = EINTR;
        } else {
                select_intr_valid = 1;
                /*
                 * Invalidate the current clock value
                 */
                clock_valid = 0;
                /*
                 * Allow interrupts.  If a signal
                 * occurs, then it will cause a longjmp
                 * up above.
                 */
                (void) sigsetmask(smask);
                /*
                 * Wait for input
                 */
                nsel = select(fds, fdp, (int *) 0, (int *) 0,
                                tvp->tv_sec ? tvp : (struct timeval *) 0);

        }

        (void) sigblock(MASKED_SIGS);

        /*
         * Perhaps reload the cache?
         */
        if (do_mapc_reload < clocktime()) {
                mapc_reload();
                do_mapc_reload = clocktime() + ONE_HOUR;
        }
        return nsel;
}

/*
 * Determine whether anything is left in
 * the RPC input queue.
 */
static int rpc_pending_now()
{
        struct timeval tvv;
        int nsel;
#ifdef FD_SET
        fd_set readfds;

        FD_ZERO(&readfds);
        FD_SET(fwd_sock, &readfds);
#else
        int readfds = (1 << fwd_sock);
#endif /* FD_SET */

        tvv.tv_sec = tvv.tv_usec = 0;
        nsel = select(max_fds+1, &readfds, (int *) 0, (int *) 0, &tvv);
        if (nsel < 1)
                return(0);
#ifdef FD_SET
        if (FD_ISSET(fwd_sock, &readfds))
                return(1);
#else
        if (readfds & (1 << fwd_sock))
                return(1);
#endif
        return(0);
}

static serv_state run_rpc(P_void)
{
        int dtbsz = max_fds + 1;
        int smask = sigblock(MASKED_SIGS);

        next_softclock = clocktime();

        amd_state = Run;

        /*
         * Keep on trucking while we are in Run mode.  This state
         * is switched to Quit after all the file systems have
         * been unmounted.
         */
        while ((int)amd_state <= (int)Finishing) {
                struct timeval tvv;
                int nsel;
                time_t now;
#ifdef RPC_4
                fd_set readfds;
                readfds = svc_fdset;
                FD_SET(fwd_sock, &readfds);
#else
#ifdef FD_SET
                fd_set readfds;
                FD_ZERO(&readfds);
                readfds.fds_bits[0] = svc_fds;
                FD_SET(fwd_sock, &readfds);
#else
                int readfds = svc_fds | (1 << fwd_sock);
#endif /* FD_SET */
#endif /* RPC_4 */

#ifdef DEBUG
                checkup();
#endif /* DEBUG */

                /*
                 * If the full timeout code is not called,
                 * then recompute the time delta manually.
                 */
                now = clocktime();

                if (next_softclock <= now) {
                        if (amd_state == Finishing)
                                umount_exported();
                        tvv.tv_sec = softclock();
                } else {
                        tvv.tv_sec = next_softclock - now;
                }
                tvv.tv_usec = 0;

                if (amd_state == Finishing && last_used_map < 0) {
                        flush_mntfs();
                        amd_state = Quit;
                        break;
                }

#ifdef DEBUG
                if (tvv.tv_sec)
                        dlog("Select waits for %ds", tvv.tv_sec);
                else
                        dlog("Select waits for Godot");
#endif /* DEBUG */

                nsel = do_select(smask, dtbsz, &readfds, &tvv);


                switch (nsel) {
                case -1:
                        if (errno == EINTR) {
#ifdef DEBUG
                                dlog("select interrupted");
#endif /* DEBUG */
                                continue;
                        }
                        perror("select");
                        break;

                case 0:
#ifdef DEBUG
                        /*dlog("select returned 0");*/
#endif /* DEBUG */
                        break;

                default:
                        /* Read all pending NFS responses at once to avoid
                           having responses queue up as a consequence of
                           retransmissions. */
#ifdef FD_SET
                        if (FD_ISSET(fwd_sock, &readfds)) {
                                FD_CLR(fwd_sock, &readfds);
#else
                        if (readfds & (1 << fwd_sock)) {
                                readfds &= ~(1 << fwd_sock);
#endif
                                --nsel;
                                do {
                                        fwd_reply();
                                } while (rpc_pending_now() > 0);
                        }

                        if (nsel) {
                                /*
                                 * Anything left must be a normal
                                 * RPC request.
                                 */
#ifdef RPC_4
                                svc_getreqset(&readfds);
#else
#ifdef FD_SET
                                svc_getreq(readfds.fds_bits[0]);
#else
                                svc_getreq(readfds);
#endif /* FD_SET */
#endif /* RPC_4 */
                        }
                        break;
                }
        }

        (void) sigsetmask(smask);

        if (amd_state == Quit)
                amd_state = Done;

        return amd_state;
}

static int bindnfs_port(so)
int so;
{
        unsigned short port;
        int error = bind_resv_port(so, &port);
        if (error == 0)
                nfs_port = port;
        return error;
}

void unregister_amq(P_void)
{
#ifdef DEBUG
        Debug(D_AMQ)
#endif /* DEBUG */
        (void) pmap_unset(AMQ_PROGRAM, AMQ_VERSION);
}

int mount_automounter(ppid)
int ppid;
{
        int so = socket(AF_INET, SOCK_DGRAM, 0);
        SVCXPRT *amqp;
        int nmount;

        if (so < 0 || bindnfs_port(so) < 0) {
                perror("Can't create privileged nfs port");
                return 1;
        }

        if ((nfsxprt = svcudp_create(so)) == NULL ||
                        (amqp = svcudp_create(so)) == NULL) {
                plog(XLOG_FATAL, "cannot create rpc/udp service");
                return 2;
        }

        if (!svc_register(nfsxprt, NFS_PROGRAM, NFS_VERSION, nfs_program_2, 0)) {
                plog(XLOG_FATAL, "unable to register (NFS_PROGRAM, NFS_VERSION, 0)");
                return 3;
        }

        /*
         * Start RPC forwarding
         */
        if (fwd_init() != 0)
                return 3;

        /*
         * One or other of so, fwd_sock
         * must be the highest fd on
         * which to select.
         */
        if (so > max_fds)
                max_fds = so;
        if (fwd_sock > max_fds)
                max_fds = fwd_sock;

        /*
         * Construct the root automount node
         */
        make_root_node();

        /*
         * Pick up the pieces from a previous run
         * This is likely to (indirectly) need the rpc_fwd package
         * so it *must* come after the call to fwd_init().
         */
        if (restart_existing_mounts)
                restart();

        /*
         * Mount the top-level auto-mountpoints
         */
        nmount = mount_exported();

        /*
         * Now safe to tell parent that we are up and running
         */
        if (ppid)
                kill(ppid, SIGQUIT);

        if (nmount == 0) {
                plog(XLOG_FATAL, "No work to do - quitting");
                amd_state = Done;
                return 0;
        }

#ifdef DEBUG
        Debug(D_AMQ) {
#endif /* DEBUG */
        /*
         * Register with amq
         */
        unregister_amq();

        if (!svc_register(amqp, AMQ_PROGRAM, AMQ_VERSION, amq_program_1, IPPROTO_UDP)) {
                plog(XLOG_FATAL, "unable to register (AMQ_PROGRAM, AMQ_VERSION, udp)");
                return 3;
        }
#ifdef DEBUG
        }
#endif /* DEBUG */

        /*
         * Start timeout_mp rolling
         */
        reschedule_timeout_mp();

        /*
         * Start the server
         */
        if (run_rpc() != Done) {
                plog(XLOG_FATAL, "run_rpc failed");
                amd_state = Done;
        }

        return 0;
}