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coda_vfsops.c revision 1.32
      1 /*	$NetBSD: coda_vfsops.c,v 1.32 2004/03/09 03:14:09 atatat Exp $	*/
      2 
      3 /*
      4  *
      5  *             Coda: an Experimental Distributed File System
      6  *                              Release 3.1
      7  *
      8  *           Copyright (c) 1987-1998 Carnegie Mellon University
      9  *                          All Rights Reserved
     10  *
     11  * Permission  to  use, copy, modify and distribute this software and its
     12  * documentation is hereby granted,  provided  that  both  the  copyright
     13  * notice  and  this  permission  notice  appear  in  all  copies  of the
     14  * software, derivative works or  modified  versions,  and  any  portions
     15  * thereof, and that both notices appear in supporting documentation, and
     16  * that credit is given to Carnegie Mellon University  in  all  documents
     17  * and publicity pertaining to direct or indirect use of this code or its
     18  * derivatives.
     19  *
     20  * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS  KNOWN  TO  HAVE  BUGS,
     21  * SOME  OF  WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON ALLOWS
     22  * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.   CARNEGIE  MELLON
     23  * DISCLAIMS  ANY  LIABILITY  OF  ANY  KIND  FOR  ANY  DAMAGES WHATSOEVER
     24  * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE  OR  OF
     25  * ANY DERIVATIVE WORK.
     26  *
     27  * Carnegie  Mellon  encourages  users  of  this  software  to return any
     28  * improvements or extensions that  they  make,  and  to  grant  Carnegie
     29  * Mellon the rights to redistribute these changes without encumbrance.
     30  *
     31  * 	@(#) cfs/coda_vfsops.c,v 1.1.1.1 1998/08/29 21:26:45 rvb Exp $
     32  */
     33 
     34 /*
     35  * Mach Operating System
     36  * Copyright (c) 1989 Carnegie-Mellon University
     37  * All rights reserved.  The CMU software License Agreement specifies
     38  * the terms and conditions for use and redistribution.
     39  */
     40 
     41 /*
     42  * This code was written for the Coda file system at Carnegie Mellon
     43  * University.  Contributers include David Steere, James Kistler, and
     44  * M. Satyanarayanan.
     45  */
     46 
     47 #include <sys/cdefs.h>
     48 __KERNEL_RCSID(0, "$NetBSD: coda_vfsops.c,v 1.32 2004/03/09 03:14:09 atatat Exp $");
     49 
     50 #ifdef	_LKM
     51 #define	NVCODA 4
     52 #else
     53 #include <vcoda.h>
     54 #endif
     55 
     56 #include <sys/param.h>
     57 #include <sys/systm.h>
     58 #include <sys/sysctl.h>
     59 #include <sys/malloc.h>
     60 #include <sys/conf.h>
     61 #include <sys/namei.h>
     62 #include <sys/mount.h>
     63 #include <sys/proc.h>
     64 #include <sys/select.h>
     65 
     66 #include <coda/coda.h>
     67 #include <coda/cnode.h>
     68 #include <coda/coda_vfsops.h>
     69 #include <coda/coda_venus.h>
     70 #include <coda/coda_subr.h>
     71 #include <coda/coda_opstats.h>
     72 /* for VN_RDEV */
     73 #include <miscfs/specfs/specdev.h>
     74 
     75 MALLOC_DEFINE(M_CODA, "coda", "Coda file system structures and tables");
     76 
     77 int codadebug = 0;
     78 
     79 int coda_vfsop_print_entry = 0;
     80 #define ENTRY if(coda_vfsop_print_entry) myprintf(("Entered %s\n",__func__))
     81 
     82 struct vnode *coda_ctlvp;
     83 struct coda_mntinfo coda_mnttbl[NVCODA]; /* indexed by minor device number */
     84 
     85 /* structure to keep statistics of internally generated/satisfied calls */
     86 
     87 struct coda_op_stats coda_vfsopstats[CODA_VFSOPS_SIZE];
     88 
     89 #define MARK_ENTRY(op) (coda_vfsopstats[op].entries++)
     90 #define MARK_INT_SAT(op) (coda_vfsopstats[op].sat_intrn++)
     91 #define MARK_INT_FAIL(op) (coda_vfsopstats[op].unsat_intrn++)
     92 #define MRAK_INT_GEN(op) (coda_vfsopstats[op].gen_intrn++)
     93 
     94 extern const struct cdevsw vcoda_cdevsw;
     95 extern const struct vnodeopv_desc coda_vnodeop_opv_desc;
     96 
     97 const struct vnodeopv_desc * const coda_vnodeopv_descs[] = {
     98 	&coda_vnodeop_opv_desc,
     99 	NULL,
    100 };
    101 
    102 struct vfsops coda_vfsops = {
    103     MOUNT_CODA,
    104     coda_mount,
    105     coda_start,
    106     coda_unmount,
    107     coda_root,
    108     coda_quotactl,
    109     coda_nb_statfs,
    110     coda_sync,
    111     coda_vget,
    112     (int (*) (struct mount *, struct fid *, struct vnode ** ))
    113 	eopnotsupp,
    114     (int (*) (struct vnode *, struct fid *)) eopnotsupp,
    115     coda_init,
    116     NULL,
    117     coda_done,
    118     NULL,
    119     (int (*)(void)) eopnotsupp,
    120     (int (*)(struct mount *, struct mbuf *, int *, struct ucred **))
    121 	eopnotsupp,
    122     coda_vnodeopv_descs,
    123     0
    124 };
    125 
    126 
    127 int
    128 coda_vfsopstats_init(void)
    129 {
    130 	int i;
    131 
    132 	for (i=0;i<CODA_VFSOPS_SIZE;i++) {
    133 		coda_vfsopstats[i].opcode = i;
    134 		coda_vfsopstats[i].entries = 0;
    135 		coda_vfsopstats[i].sat_intrn = 0;
    136 		coda_vfsopstats[i].unsat_intrn = 0;
    137 		coda_vfsopstats[i].gen_intrn = 0;
    138 	}
    139 
    140 	return 0;
    141 }
    142 
    143 /*
    144  * cfs mount vfsop
    145  * Set up mount info record and attach it to vfs struct.
    146  */
    147 /*ARGSUSED*/
    148 int
    149 coda_mount(vfsp, path, data, ndp, p)
    150     struct mount *vfsp;		/* Allocated and initialized by mount(2) */
    151     const char *path;		/* path covered: ignored by the fs-layer */
    152     void *data;			/* Need to define a data type for this in netbsd? */
    153     struct nameidata *ndp;	/* Clobber this to lookup the device name */
    154     struct proc *p;		/* The ever-famous proc pointer */
    155 {
    156     struct vnode *dvp;
    157     struct cnode *cp;
    158     dev_t dev;
    159     struct coda_mntinfo *mi;
    160     struct vnode *rootvp;
    161     const struct cdevsw *cdev;
    162     CodaFid rootfid = INVAL_FID;
    163     CodaFid ctlfid = CTL_FID;
    164     int error;
    165 
    166     if (vfsp->mnt_flag & MNT_GETARGS)
    167 	return 0;
    168     ENTRY;
    169 
    170     coda_vfsopstats_init();
    171     coda_vnodeopstats_init();
    172 
    173     MARK_ENTRY(CODA_MOUNT_STATS);
    174     if (CODA_MOUNTED(vfsp)) {
    175 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    176 	return(EBUSY);
    177     }
    178 
    179     /* Validate mount device.  Similar to getmdev(). */
    180 
    181     NDINIT(ndp, LOOKUP, FOLLOW, UIO_USERSPACE, data, p);
    182     error = namei(ndp);
    183     dvp = ndp->ni_vp;
    184 
    185     if (error) {
    186 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    187 	return (error);
    188     }
    189     if (dvp->v_type != VCHR) {
    190 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    191 	vrele(dvp);
    192 	return(ENXIO);
    193     }
    194     dev = dvp->v_specinfo->si_rdev;
    195     vrele(dvp);
    196     cdev = cdevsw_lookup(dev);
    197     if (cdev == NULL) {
    198 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    199 	return(ENXIO);
    200     }
    201 
    202     /*
    203      * See if the device table matches our expectations.
    204      */
    205     if (cdev != &vcoda_cdevsw)
    206     {
    207 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    208 	return(ENXIO);
    209     }
    210 
    211     if (minor(dev) >= NVCODA || minor(dev) < 0) {
    212 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    213 	return(ENXIO);
    214     }
    215 
    216     /*
    217      * Initialize the mount record and link it to the vfs struct
    218      */
    219     mi = &coda_mnttbl[minor(dev)];
    220 
    221     if (!VC_OPEN(&mi->mi_vcomm)) {
    222 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    223 	return(ENODEV);
    224     }
    225 
    226     /* No initialization (here) of mi_vcomm! */
    227     vfsp->mnt_data = mi;
    228     vfsp->mnt_stat.f_fsid.val[0] = 0;
    229     vfsp->mnt_stat.f_fsid.val[1] = makefstype(MOUNT_CODA);
    230     mi->mi_vfsp = vfsp;
    231 
    232     /*
    233      * Make a root vnode to placate the Vnode interface, but don't
    234      * actually make the CODA_ROOT call to venus until the first call
    235      * to coda_root in case a server is down while venus is starting.
    236      */
    237     cp = make_coda_node(&rootfid, vfsp, VDIR);
    238     rootvp = CTOV(cp);
    239     rootvp->v_flag |= VROOT;
    240 
    241 /*  cp = make_coda_node(&ctlfid, vfsp, VCHR);
    242     The above code seems to cause a loop in the cnode links.
    243     I don't totally understand when it happens, it is caught
    244     when closing down the system.
    245  */
    246     cp = make_coda_node(&ctlfid, 0, VCHR);
    247 
    248     coda_ctlvp = CTOV(cp);
    249 
    250     /* Add vfs and rootvp to chain of vfs hanging off mntinfo */
    251     mi->mi_vfsp = vfsp;
    252     mi->mi_rootvp = rootvp;
    253 
    254     /* set filesystem block size */
    255     vfsp->mnt_stat.f_bsize = 8192;	    /* XXX -JJK */
    256 
    257     /* error is currently guaranteed to be zero, but in case some
    258        code changes... */
    259     CODADEBUG(1,
    260 	     myprintf(("coda_mount returned %d\n",error)););
    261     if (error)
    262 	MARK_INT_FAIL(CODA_MOUNT_STATS);
    263     else
    264 	MARK_INT_SAT(CODA_MOUNT_STATS);
    265 
    266     return set_statfs_info("/coda", UIO_SYSSPACE, "CODA", UIO_SYSSPACE, vfsp,
    267 	p);
    268 }
    269 
    270 int
    271 coda_start(vfsp, flags, p)
    272     struct mount *vfsp;
    273     int flags;
    274     struct proc *p;
    275 {
    276     ENTRY;
    277     vftomi(vfsp)->mi_started = 1;
    278     return (0);
    279 }
    280 
    281 int
    282 coda_unmount(vfsp, mntflags, p)
    283     struct mount *vfsp;
    284     int mntflags;
    285     struct proc *p;
    286 {
    287     struct coda_mntinfo *mi = vftomi(vfsp);
    288     int active, error = 0;
    289 
    290     ENTRY;
    291     MARK_ENTRY(CODA_UMOUNT_STATS);
    292     if (!CODA_MOUNTED(vfsp)) {
    293 	MARK_INT_FAIL(CODA_UMOUNT_STATS);
    294 	return(EINVAL);
    295     }
    296 
    297     if (mi->mi_vfsp == vfsp) {	/* We found the victim */
    298 	if (!IS_UNMOUNTING(VTOC(mi->mi_rootvp)))
    299 	    return (EBUSY); 	/* Venus is still running */
    300 
    301 #ifdef	DEBUG
    302 	printf("coda_unmount: ROOT: vp %p, cp %p\n", mi->mi_rootvp, VTOC(mi->mi_rootvp));
    303 #endif
    304 	mi->mi_started = 0;
    305 
    306 	vrele(mi->mi_rootvp);
    307 
    308 	active = coda_kill(vfsp, NOT_DOWNCALL);
    309 	mi->mi_rootvp->v_flag &= ~VROOT;
    310 	error = vflush(mi->mi_vfsp, NULLVP, FORCECLOSE);
    311 	printf("coda_unmount: active = %d, vflush active %d\n", active, error);
    312 	error = 0;
    313 
    314 	/* I'm going to take this out to allow lookups to go through. I'm
    315 	 * not sure it's important anyway. -- DCS 2/2/94
    316 	 */
    317 	/* vfsp->VFS_DATA = NULL; */
    318 
    319 	/* No more vfsp's to hold onto */
    320 	mi->mi_vfsp = NULL;
    321 	mi->mi_rootvp = NULL;
    322 
    323 	if (error)
    324 	    MARK_INT_FAIL(CODA_UMOUNT_STATS);
    325 	else
    326 	    MARK_INT_SAT(CODA_UMOUNT_STATS);
    327 
    328 	return(error);
    329     }
    330     return (EINVAL);
    331 }
    332 
    333 /*
    334  * find root of cfs
    335  */
    336 int
    337 coda_root(vfsp, vpp)
    338 	struct mount *vfsp;
    339 	struct vnode **vpp;
    340 {
    341     struct coda_mntinfo *mi = vftomi(vfsp);
    342     int error;
    343     struct proc *p = curproc;    /* XXX - bnoble */
    344     CodaFid VFid;
    345     static const CodaFid invalfid = INVAL_FID;
    346 
    347     ENTRY;
    348     MARK_ENTRY(CODA_ROOT_STATS);
    349 
    350     if (vfsp == mi->mi_vfsp) {
    351     	if (memcmp(&VTOC(mi->mi_rootvp)->c_fid, &invalfid, sizeof(CodaFid)))
    352 	    { /* Found valid root. */
    353 		*vpp = mi->mi_rootvp;
    354 		/* On Mach, this is vref.  On NetBSD, VOP_LOCK */
    355 		vref(*vpp);
    356 		vn_lock(*vpp, LK_EXCLUSIVE);
    357 		MARK_INT_SAT(CODA_ROOT_STATS);
    358 		return(0);
    359 	    }
    360     }
    361 
    362     error = venus_root(vftomi(vfsp), p->p_cred->pc_ucred, p, &VFid);
    363 
    364     if (!error) {
    365 	/*
    366 	 * Save the new rootfid in the cnode, and rehash the cnode into the
    367 	 * cnode hash with the new fid key.
    368 	 */
    369 	coda_unsave(VTOC(mi->mi_rootvp));
    370 	VTOC(mi->mi_rootvp)->c_fid = VFid;
    371 	coda_save(VTOC(mi->mi_rootvp));
    372 
    373 	*vpp = mi->mi_rootvp;
    374 	vref(*vpp);
    375 	vn_lock(*vpp, LK_EXCLUSIVE);
    376 	MARK_INT_SAT(CODA_ROOT_STATS);
    377 	goto exit;
    378     } else if (error == ENODEV || error == EINTR) {
    379 	/* Gross hack here! */
    380 	/*
    381 	 * If Venus fails to respond to the CODA_ROOT call, coda_call returns
    382 	 * ENODEV. Return the uninitialized root vnode to allow vfs
    383 	 * operations such as unmount to continue. Without this hack,
    384 	 * there is no way to do an unmount if Venus dies before a
    385 	 * successful CODA_ROOT call is done. All vnode operations
    386 	 * will fail.
    387 	 */
    388 	*vpp = mi->mi_rootvp;
    389 	vref(*vpp);
    390 	vn_lock(*vpp, LK_EXCLUSIVE);
    391 	MARK_INT_FAIL(CODA_ROOT_STATS);
    392 	error = 0;
    393 	goto exit;
    394     } else {
    395 	CODADEBUG( CODA_ROOT, myprintf(("error %d in CODA_ROOT\n", error)); );
    396 	MARK_INT_FAIL(CODA_ROOT_STATS);
    397 
    398 	goto exit;
    399     }
    400  exit:
    401     return(error);
    402 }
    403 
    404 int
    405 coda_quotactl(vfsp, cmd, uid, arg, p)
    406     struct mount *vfsp;
    407     int cmd;
    408     uid_t uid;
    409     caddr_t arg;
    410     struct proc *p;
    411 {
    412     ENTRY;
    413     return (EOPNOTSUPP);
    414 }
    415 
    416 /*
    417  * Get file system statistics.
    418  */
    419 int
    420 coda_nb_statfs(vfsp, sbp, p)
    421     struct mount *vfsp;
    422     struct statfs *sbp;
    423     struct proc *p;
    424 {
    425     struct coda_statfs fsstat;
    426     int error;
    427 
    428     ENTRY;
    429     MARK_ENTRY(CODA_STATFS_STATS);
    430     if (!CODA_MOUNTED(vfsp)) {
    431 /*	MARK_INT_FAIL(CODA_STATFS_STATS); */
    432 	return(EINVAL);
    433     }
    434 
    435     /* XXX - what to do about f_flags, others? --bnoble */
    436     /* Below This is what AFS does
    437     	#define NB_SFS_SIZ 0x895440
    438      */
    439     /* Note: Normal fs's have a bsize of 0x400 == 1024 */
    440 
    441     error = venus_statfs(vftomi(vfsp), p->p_cred->pc_ucred, p, &fsstat);
    442 
    443     if (!error) {
    444 	sbp->f_type = 0;
    445 	sbp->f_bsize = 8192; /* XXX */
    446 	sbp->f_iosize = 8192; /* XXX */
    447 	sbp->f_blocks = fsstat.f_blocks;
    448 	sbp->f_bfree  = fsstat.f_bfree;
    449 	sbp->f_bavail = fsstat.f_bavail;
    450 	sbp->f_files  = fsstat.f_files;
    451 	sbp->f_ffree  = fsstat.f_ffree;
    452 	copy_statfs_info(sbp, vfsp);
    453     }
    454 
    455     MARK_INT_SAT(CODA_STATFS_STATS);
    456     return(error);
    457 }
    458 
    459 /*
    460  * Flush any pending I/O.
    461  */
    462 int
    463 coda_sync(vfsp, waitfor, cred, p)
    464     struct mount *vfsp;
    465     int    waitfor;
    466     struct ucred *cred;
    467     struct proc *p;
    468 {
    469     ENTRY;
    470     MARK_ENTRY(CODA_SYNC_STATS);
    471     MARK_INT_SAT(CODA_SYNC_STATS);
    472     return(0);
    473 }
    474 
    475 int
    476 coda_vget(vfsp, ino, vpp)
    477     struct mount *vfsp;
    478     ino_t ino;
    479     struct vnode **vpp;
    480 {
    481     ENTRY;
    482     return (EOPNOTSUPP);
    483 }
    484 
    485 /*
    486  * fhtovp is now what vget used to be in 4.3-derived systems.  For
    487  * some silly reason, vget is now keyed by a 32 bit ino_t, rather than
    488  * a type-specific fid.
    489  */
    490 int
    491 coda_fhtovp(vfsp, fhp, nam, vpp, exflagsp, creadanonp)
    492     struct mount *vfsp;
    493     struct fid *fhp;
    494     struct mbuf *nam;
    495     struct vnode **vpp;
    496     int *exflagsp;
    497     struct ucred **creadanonp;
    498 {
    499     struct cfid *cfid = (struct cfid *)fhp;
    500     struct cnode *cp = 0;
    501     int error;
    502     struct proc *p = curproc; /* XXX -mach */
    503     CodaFid VFid;
    504     int vtype;
    505 
    506     ENTRY;
    507 
    508     MARK_ENTRY(CODA_VGET_STATS);
    509     /* Check for vget of control object. */
    510     if (IS_CTL_FID(&cfid->cfid_fid)) {
    511 	*vpp = coda_ctlvp;
    512 	vref(coda_ctlvp);
    513 	MARK_INT_SAT(CODA_VGET_STATS);
    514 	return(0);
    515     }
    516 
    517     error = venus_fhtovp(vftomi(vfsp), &cfid->cfid_fid, p->p_cred->pc_ucred, p, &VFid, &vtype);
    518 
    519     if (error) {
    520 	CODADEBUG(CODA_VGET, myprintf(("vget error %d\n",error));)
    521 	    *vpp = (struct vnode *)0;
    522     } else {
    523 	CODADEBUG(CODA_VGET,
    524 		 myprintf(("vget: %s type %d result %d\n",
    525 			coda_f2s(&VFid), vtype, error)); )
    526 
    527 	cp = make_coda_node(&VFid, vfsp, vtype);
    528 	*vpp = CTOV(cp);
    529     }
    530     return(error);
    531 }
    532 
    533 int
    534 coda_vptofh(vnp, fidp)
    535     struct vnode *vnp;
    536     struct fid   *fidp;
    537 {
    538     ENTRY;
    539     return (EOPNOTSUPP);
    540 }
    541 
    542 void
    543 coda_init(void)
    544 {
    545     ENTRY;
    546 }
    547 
    548 void
    549 coda_done(void)
    550 {
    551     ENTRY;
    552 }
    553 
    554 SYSCTL_SETUP(sysctl_vfs_coda_setup, "sysctl vfs.coda subtree setup")
    555 {
    556 	sysctl_createv(SYSCTL_PERMANENT,
    557 		       CTLTYPE_NODE, "vfs", NULL,
    558 		       NULL, 0, NULL, 0,
    559 		       CTL_VFS, CTL_EOL);
    560 	sysctl_createv(SYSCTL_PERMANENT,
    561 		       CTLTYPE_NODE, "coda", NULL,
    562 		       NULL, 0, NULL, 0,
    563 		       CTL_VFS, 18, CTL_EOL);
    564 	/*
    565 	 * XXX the "18" above could be dynamic, thereby eliminating
    566 	 * one more instance of the "number to vfs" mapping problem,
    567 	 * but "18" is the order as taken from sys/mount.h
    568 	 */
    569 
    570 /*
    571 	sysctl_createv(SYSCTL_PERMANENT|SYSCTL_READWRITE,
    572 		       CTLTYPE_INT, "clusterread", NULL,
    573 		       NULL, 0, &doclusterread, 0,
    574 		       CTL_VFS, 18, FFS_CLUSTERREAD, CTL_EOL);
    575 */
    576 }
    577 
    578 /*
    579  * To allow for greater ease of use, some vnodes may be orphaned when
    580  * Venus dies.  Certain operations should still be allowed to go
    581  * through, but without propagating orphan-ness.  So this function will
    582  * get a new vnode for the file from the current run of Venus.
    583  */
    584 
    585 int
    586 getNewVnode(vpp)
    587      struct vnode **vpp;
    588 {
    589     struct cfid cfid;
    590     struct coda_mntinfo *mi = vftomi((*vpp)->v_mount);
    591 
    592     ENTRY;
    593 
    594     cfid.cfid_len = (short)sizeof(CodaFid);
    595     cfid.cfid_fid = VTOC(*vpp)->c_fid;	/* Structure assignment. */
    596     /* XXX ? */
    597 
    598     /* We're guessing that if set, the 1st element on the list is a
    599      * valid vnode to use. If not, return ENODEV as venus is dead.
    600      */
    601     if (mi->mi_vfsp == NULL)
    602 	return ENODEV;
    603 
    604     return coda_fhtovp(mi->mi_vfsp, (struct fid*)&cfid, NULL, vpp,
    605 		      NULL, NULL);
    606 }
    607 
    608 #include <ufs/ufs/quota.h>
    609 #include <ufs/ufs/ufsmount.h>
    610 /* get the mount structure corresponding to a given device.  Assume
    611  * device corresponds to a UFS. Return NULL if no device is found.
    612  */
    613 struct mount *devtomp(dev)
    614     dev_t dev;
    615 {
    616     struct mount *mp, *nmp;
    617 
    618     for (mp = mountlist.cqh_first; mp != (void*)&mountlist; mp = nmp) {
    619 	nmp = mp->mnt_list.cqe_next;
    620 	if ((!strcmp(mp->mnt_op->vfs_name, MOUNT_UFS)) &&
    621 	    ((VFSTOUFS(mp))->um_dev == (dev_t) dev)) {
    622 	    /* mount corresponds to UFS and the device matches one we want */
    623 	    return(mp);
    624 	}
    625     }
    626     /* mount structure wasn't found */
    627     return(NULL);
    628 }
    629