usr/src/sys.386bsd/nfs/nfs_syscalls.c

/*
 * Copyright (c) 1989 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * 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.
 *
 *      @(#)nfs_syscalls.c      7.26 (Berkeley) 4/16/91
 */

#include "param.h"
#include "systm.h"
#include "kernel.h"
#include "file.h"
#include "stat.h"
#include "namei.h"
#include "vnode.h"
#include "mount.h"
#include "proc.h"
#include "malloc.h"
#include "buf.h"
#include "mbuf.h"
#include "socket.h"
#include "socketvar.h"
#include "domain.h"
#include "protosw.h"

#include "../netinet/in.h"
#include "../netinet/tcp.h"

#include "nfsv2.h"
#include "nfs.h"
#include "nfsrvcache.h"

/* Global defs. */
extern u_long nfs_prog, nfs_vers;
extern int (*nfsrv_procs[NFS_NPROCS])();
extern struct buf nfs_bqueue;
extern int nfs_numasync;
extern struct proc *nfs_iodwant[NFS_MAXASYNCDAEMON];
extern int nfs_tcpnodelay;
struct mbuf *nfs_compress();

#define TRUE    1
#define FALSE   0

static int nfs_asyncdaemon[NFS_MAXASYNCDAEMON];
static int compressreply[NFS_NPROCS] = {
        FALSE,
        TRUE,
        TRUE,
        FALSE,
        TRUE,
        TRUE,
        FALSE,
        FALSE,
        TRUE,
        TRUE,
        TRUE,
        TRUE,
        TRUE,
        TRUE,
        TRUE,
        TRUE,
        TRUE,
        TRUE,
};
/*
 * NFS server system calls
 * getfh() lives here too, but maybe should move to kern/vfs_syscalls.c
 */

/*
 * Get file handle system call
 */
/* ARGSUSED */
getfh(p, uap, retval)
        struct proc *p;
        register struct args {
                char    *fname;
                fhandle_t *fhp;
        } *uap;
        int *retval;
{
        register struct nameidata *ndp;
        register struct vnode *vp;
        fhandle_t fh;
        int error;
        struct nameidata nd;

        /*
         * Must be super user
         */
        if (error = suser(p->p_ucred, &p->p_acflag))
                return (error);
        ndp = &nd;
        ndp->ni_nameiop = LOOKUP | LOCKLEAF | FOLLOW;
        ndp->ni_segflg = UIO_USERSPACE;
        ndp->ni_dirp = uap->fname;
        if (error = namei(ndp, p))
                return (error);
        vp = ndp->ni_vp;
        bzero((caddr_t)&fh, sizeof(fh));
        fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
        error = VFS_VPTOFH(vp, &fh.fh_fid);
        vput(vp);
        if (error)
                return (error);
        error = copyout((caddr_t)&fh, (caddr_t)uap->fhp, sizeof (fh));
        return (error);
}

/*
 * Nfs server psuedo system call for the nfsd's
 * Never returns unless it fails or gets killed
 */
/* ARGSUSED */
nfssvc(p, uap, retval)
        struct proc *p;
        register struct args {
                int s;
                caddr_t mskval;
                int msklen;
                caddr_t mtchval;
                int mtchlen;
        } *uap;
        int *retval;
{
        register struct mbuf *m;
        register int siz;
        register struct ucred *cr;
        struct file *fp;
        struct mbuf *mreq, *mrep, *nam, *md;
        struct mbuf msk, mtch;
        struct socket *so;
        caddr_t dpos;
        int procid, repstat, error, cacherep, wascomp;
        u_long retxid;

        /*
         * Must be super user
         */
        if (error = suser(p->p_ucred, &p->p_acflag))
                return (error);
        if (error = getsock(p->p_fd, uap->s, &fp))
                return (error);
        so = (struct socket *)fp->f_data;
        if (sosendallatonce(so))
                siz = NFS_MAXPACKET;
        else
                siz = NFS_MAXPACKET + sizeof(u_long);
        if (error = soreserve(so, siz, siz))
                goto bad;
        if (error = sockargs(&nam, uap->mskval, uap->msklen, MT_SONAME))
                goto bad;
        bcopy((caddr_t)nam, (caddr_t)&msk, sizeof (struct mbuf));
        msk.m_data = msk.m_dat;
        m_freem(nam);
        if (error = sockargs(&nam, uap->mtchval, uap->mtchlen, MT_SONAME))
                goto bad;
        bcopy((caddr_t)nam, (caddr_t)&mtch, sizeof (struct mbuf));
        mtch.m_data = mtch.m_dat;
        m_freem(nam);

        /* Copy the cred so others don't see changes */
        cr = p->p_ucred = crcopy(p->p_ucred);

        /*
         * Set protocol specific options { for now TCP only } and
         * reserve some space. For datagram sockets, this can get called
         * repeatedly for the same socket, but that isn't harmful.
         */
        if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
                MGET(m, M_WAIT, MT_SOOPTS);
                *mtod(m, int *) = 1;
                m->m_len = sizeof(int);
                sosetopt(so, SOL_SOCKET, SO_KEEPALIVE, m);
        }
        if (so->so_proto->pr_domain->dom_family == AF_INET &&
            so->so_proto->pr_protocol == IPPROTO_TCP &&
            nfs_tcpnodelay) {
                MGET(m, M_WAIT, MT_SOOPTS);
                *mtod(m, int *) = 1;
                m->m_len = sizeof(int);
                sosetopt(so, IPPROTO_TCP, TCP_NODELAY, m);
        }
        so->so_rcv.sb_flags &= ~SB_NOINTR;
        so->so_rcv.sb_timeo = 0;
        so->so_snd.sb_flags &= ~SB_NOINTR;
        so->so_snd.sb_timeo = 0;

        /*
         * Just loop around doin our stuff until SIGKILL
         */
        for (;;) {
                if (error = nfs_getreq(so, nfs_prog, nfs_vers, NFS_NPROCS-1,
                   &nam, &mrep, &md, &dpos, &retxid, &procid, cr,
                   &msk, &mtch, &wascomp)) {
                        if (nam)
                                m_freem(nam);
                        if (error == EPIPE || error == EINTR ||
                            error == ERESTART) {
                                error = 0;
                                goto bad;
                        }
                        so->so_error = 0;
                        continue;
                }

                if (nam)
                        cacherep = nfsrv_getcache(nam, retxid, procid, &mreq);
                else
                        cacherep = RC_DOIT;
                switch (cacherep) {
                case RC_DOIT:
                        if (error = (*(nfsrv_procs[procid]))(mrep, md, dpos,
                                cr, retxid, &mreq, &repstat, p)) {
                                nfsstats.srv_errs++;
                                if (nam) {
                                        nfsrv_updatecache(nam, retxid, procid,
                                                FALSE, repstat, mreq);
                                        m_freem(nam);
                                }
                                break;
                        }
                        nfsstats.srvrpccnt[procid]++;
                        if (nam)
                                nfsrv_updatecache(nam, retxid, procid, TRUE,
                                        repstat, mreq);
                        mrep = (struct mbuf *)0;
                case RC_REPLY:
                        m = mreq;
                        siz = 0;
                        while (m) {
                                siz += m->m_len;
                                m = m->m_next;
                        }
                        if (siz <= 0 || siz > NFS_MAXPACKET) {
                                printf("mbuf siz=%d\n",siz);
                                panic("Bad nfs svc reply");
                        }
                        mreq->m_pkthdr.len = siz;
                        mreq->m_pkthdr.rcvif = (struct ifnet *)0;
                        if (wascomp && compressreply[procid]) {
                                mreq = nfs_compress(mreq);
                                siz = mreq->m_pkthdr.len;
                        }
                        /*
                         * For non-atomic protocols, prepend a Sun RPC
                         * Record Mark.
                         */
                        if (!sosendallatonce(so)) {
                                M_PREPEND(mreq, sizeof(u_long), M_WAIT);
                                *mtod(mreq, u_long *) = htonl(0x80000000 | siz);
                        }
                        error = nfs_send(so, nam, mreq, (struct nfsreq *)0);
                        if (nam)
                                m_freem(nam);
                        if (mrep)
                                m_freem(mrep);
                        if (error) {
                                if (error == EPIPE || error == EINTR ||
                                    error == ERESTART)
                                        goto bad;
                                so->so_error = 0;
                        }
                        break;
                case RC_DROPIT:
                        m_freem(mrep);
                        m_freem(nam);
                        break;
                };
        }
bad:
        return (error);
}

/*
 * Nfs pseudo system call for asynchronous i/o daemons.
 * These babies just pretend to be disk interrupt service routines
 * for client nfs. They are mainly here for read ahead/write behind.
 * Never returns unless it fails or gets killed
 */
/* ARGSUSED */
async_daemon(p, uap, retval)
        struct proc *p;
        struct args *uap;
        int *retval;
{
        register struct buf *bp, *dp;
        register int i, myiod;
        int error;

        /*
         * Must be super user
         */
        if (error = suser(p->p_ucred, &p->p_acflag))
                return (error);
        /*
         * Assign my position or return error if too many already running
         */
        myiod = -1;
        for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
                if (nfs_asyncdaemon[i] == 0) {
                        nfs_asyncdaemon[i]++;
                        myiod = i;
                        break;
                }
        if (myiod == -1)
                return (EBUSY);
        nfs_numasync++;
        dp = &nfs_bqueue;
        /*
         * Just loop around doin our stuff until SIGKILL
         */
        for (;;) {
                while (dp->b_actf == NULL && error == 0) {
                        nfs_iodwant[myiod] = p;
                        error = tsleep((caddr_t)&nfs_iodwant[myiod],
                                PWAIT | PCATCH, "nfsidl", 0);
                        nfs_iodwant[myiod] = (struct proc *)0;
                }
                while (dp->b_actf != NULL) {
                        /* Take one off the end of the list */
                        bp = dp->b_actl;
                        if (bp->b_actl == dp) {
                                dp->b_actf = dp->b_actl = (struct buf *)0;
                        } else {
                                dp->b_actl = bp->b_actl;
                                bp->b_actl->b_actf = dp;
                        }
                        (void) nfs_doio(bp);
                }
                if (error) {
                        nfs_asyncdaemon[myiod] = 0;
                        nfs_numasync--;
                        return (error);
                }
        }
}