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kernfs_vnops.c revision 1.14
      1 /*
      2  * Copyright (c) 1990, 1992 Jan-Simon Pendry
      3  * All rights reserved.
      4  *
      5  * This code is derived from software contributed to Berkeley by
      6  * Jan-Simon Pendry.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  * 3. All advertising materials mentioning features or use of this software
     17  *    must display the following acknowledgement:
     18  *      This product includes software developed by the University of
     19  *      California, Berkeley and its contributors.
     20  * 4. Neither the name of the University nor the names of its contributors
     21  *    may be used to endorse or promote products derived from this software
     22  *    without specific prior written permission.
     23  *
     24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     34  * SUCH DAMAGE.
     35  *
     36  *	$Id: kernfs_vnops.c,v 1.14 1993/12/18 03:56:12 mycroft Exp $
     37  */
     38 
     39 /*
     40  * Kernel parameter filesystem
     41  */
     42 
     43 #include <sys/param.h>
     44 #include <sys/systm.h>
     45 #include <sys/kernel.h>
     46 #include <sys/types.h>
     47 #include <sys/time.h>
     48 #include <sys/proc.h>
     49 #include <sys/file.h>
     50 #include <sys/vnode.h>
     51 #include <sys/stat.h>
     52 #include <sys/mount.h>
     53 #include <sys/namei.h>
     54 #include <sys/buf.h>
     55 
     56 #include <ufs/dir.h>		/* For readdir() XXX */
     57 
     58 #include <miscfs/kernfs/kernfs.h>
     59 
     60 struct kernfs_target kernfs_targets[] = {
     61 /* NOTE: The name must be less than UIO_MX-16 chars in length */
     62 DIR_TARGET(".",		0,		KTT_NULL,	KTM_DIR_PERMS	)
     63 DIR_TARGET("..",	0,		KTT_NULL,	KTM_DIR_PERMS	)
     64 REG_TARGET("copyright",	copyright,	KTT_STRING,	KTM_RO_PERMS	)
     65 REG_TARGET("hostname",	0,		KTT_HOSTNAME,	KTM_RW_PERMS	)
     66 REG_TARGET("hz",	&hz,		KTT_INT,	KTM_RO_PERMS	)
     67 REG_TARGET("loadavg",	0,		KTT_AVENRUN,	KTM_RO_PERMS	)
     68 REG_TARGET("physmem",	&physmem,	KTT_INT,	KTM_RO_PERMS	)
     69 #ifdef KERNFS_HAVE_ROOTDIR
     70 DIR_TARGET("root",	0,		KTT_NULL,	KTM_DIR_PERMS	)
     71 #endif
     72 BLK_TARGET("rootdev",	0,		KTT_NULL,	KTM_RO_PERMS	)
     73 CHR_TARGET("rrootdev",	0,		KTT_NULL,	KTM_RO_PERMS	)
     74 REG_TARGET("time",	0,		KTT_TIME,	KTM_RO_PERMS	)
     75 REG_TARGET("version",	version,	KTT_STRING,	KTM_RO_PERMS	)
     76 };
     77 
     78 static int nkernfs_targets = sizeof(kernfs_targets) / sizeof(kernfs_targets[0]);
     79 
     80 static int
     81 kernfs_xread(kt, buf, len, lenp)
     82 	struct kernfs_target *kt;
     83 	char *buf;
     84 	int len;
     85 	int *lenp;
     86 {
     87 	int xlen;
     88 
     89 	switch (kt->kt_tag) {
     90 	case KTT_TIME: {
     91 		struct timeval tv;
     92 		microtime(&tv);
     93 		sprintf(buf, "%d %d\n", tv.tv_sec, tv.tv_usec);
     94 		break;
     95 	}
     96 
     97 	case KTT_INT: {
     98 		int *ip = kt->kt_data;
     99 		sprintf(buf, "%d\n", *ip);
    100 		break;
    101 	}
    102 
    103 	case KTT_STRING: {
    104 		char *cp = kt->kt_data;
    105 		int xlen = strlen(cp) + 1;
    106 
    107 		if (xlen >= len)
    108 			return (EINVAL);
    109 
    110 		bcopy(cp, buf, xlen);
    111 		break;
    112 	}
    113 
    114 	case KTT_HOSTNAME: {
    115 		char *cp = hostname;
    116 		int xlen = hostnamelen;
    117 
    118 		if (xlen + 2 > len)	/* extra space for null and newline */
    119 			return (EINVAL);
    120 
    121 		bcopy(cp, buf, xlen);	/* safer than sprintf */
    122 		buf[xlen] = '\n';
    123 		buf[xlen+1] = '\0';
    124 		break;
    125 	}
    126 
    127 	case KTT_AVENRUN:
    128 		sprintf(buf, "%d %d %d %d\n",
    129 				averunnable[0],
    130 				averunnable[1],
    131 				averunnable[2],
    132 				FSCALE);
    133 		break;
    134 
    135 	default:
    136 		return (EINVAL);
    137 	}
    138 
    139 	*lenp = strlen(buf);
    140 	return (0);
    141 }
    142 
    143 static int
    144 kernfs_xwrite(kt, buf, len)
    145 	struct kernfs_target *kt;
    146 	char *buf;
    147 	int len;
    148 {
    149 	switch (kt->kt_tag) {
    150 	case KTT_HOSTNAME: {
    151 		if (buf[len-1] == '\n')
    152 			--len;
    153 		bcopy(buf, hostname, len);
    154 		/* kernfs_write set buf[value_passed_as_len] = \0.
    155 		 * therefore, buf len (hostnamelen) = len.
    156 		 */
    157 		hostnamelen = len;
    158 		hostname[hostnamelen] = '\0';	/* null end of string. */
    159 		return (0);
    160 	}
    161 
    162 	default:
    163 		return (EIO);
    164 	}
    165 }
    166 
    167 /*
    168  * vp is the current namei directory
    169  * ndp is the name to locate in that directory...
    170  */
    171 kernfs_lookup(dvp, ndp, p)
    172 	struct vnode *dvp;
    173 	struct nameidata *ndp;
    174 	struct proc *p;
    175 {
    176 	char *pname = ndp->ni_ptr;
    177 	int error = ENOENT;
    178 	int i;
    179 	struct vnode *fvp;
    180 
    181 #ifdef KERNFS_DIAGNOSTIC
    182 	printf("kernfs_lookup(%s)\n", pname);
    183 #endif
    184 	if (ndp->ni_namelen == 1 && *pname == '.') {
    185 		ndp->ni_dvp = dvp;
    186 		ndp->ni_vp = dvp;
    187 		VREF(dvp);
    188 		/*VOP_LOCK(dvp);*/
    189 		return (0);
    190 	}
    191 
    192 #ifdef KERNFS_HAVE_ROOTDIR
    193 	if (ndp->ni_namelen == 4 && bcmp(pname, "root", 4) == 0) {
    194 		ndp->ni_dvp = dvp;
    195 		ndp->ni_vp = rootdir;
    196 		VREF(rootdir);
    197 		VOP_LOCK(rootdir);
    198 		return (0);
    199 	}
    200 #endif
    201 
    202 	/*
    203 	 * /kern/rootdev is the root device
    204 	 */
    205 	if (ndp->ni_namelen == 7 && bcmp(pname, "rootdev", 7) == 0) {
    206 		if (vfinddev(rootdev, VBLK, &fvp))
    207 			return (ENXIO);
    208 		ndp->ni_dvp = dvp;
    209 		ndp->ni_vp = fvp;
    210 		VREF(fvp);
    211 		VOP_LOCK(fvp);
    212 		return (0);
    213 	}
    214 
    215 	/*
    216 	 * /kern/rrootdev is the root device
    217 	 */
    218 	if (ndp->ni_namelen == 8 && bcmp(pname, "rrootdev", 7) == 0) {
    219 		ndp->ni_dvp = dvp;
    220 		ndp->ni_vp = rrootdevvp;
    221 		VREF(rrootdevvp);
    222 		VOP_LOCK(rrootdevvp);
    223 		return (0);
    224 	}
    225 
    226 	for (i = 0; i < nkernfs_targets; i++) {
    227 		struct kernfs_target *kt = &kernfs_targets[i];
    228 		if (ndp->ni_namelen == strlen(kt->kt_name) &&
    229 		    bcmp(kt->kt_name, pname, ndp->ni_namelen) == 0) {
    230 			error = 0;
    231 			break;
    232 		}
    233 	}
    234 
    235 #ifdef KERNFS_DIAGNOSTIC
    236 	printf("kernfs_lookup: i = %d, error = %d\n", i, error);
    237 #endif
    238 
    239 	if (error)
    240 		goto bad;
    241 
    242 #ifdef KERNFS_DIAGNOSTIC
    243 	printf("kernfs_lookup: allocate new vnode\n");
    244 #endif
    245 	error = getnewvnode(VT_KERNFS, dvp->v_mount, &kernfs_vnodeops, &fvp);
    246 	if (error)
    247 		goto bad;
    248 	VTOKERN(fvp)->kf_kt = &kernfs_targets[i];
    249 	fvp->v_type = VTOKERN(fvp)->kf_kt->kt_vtype;
    250 	ndp->ni_dvp = dvp;
    251 	ndp->ni_vp = fvp;
    252 #ifdef KERNFS_DIAGNOSTIC
    253 	printf("kernfs_lookup: newvp = %x\n", fvp);
    254 #endif
    255 	return (0);
    256 
    257 bad:;
    258 	ndp->ni_dvp = dvp;
    259 	ndp->ni_vp = NULL;
    260 #ifdef KERNFS_DIAGNOSTIC
    261 	printf("kernfs_lookup: error = %d\n", error);
    262 #endif
    263 	return (error);
    264 }
    265 
    266 kernfs_open(vp, mode, cred, p)
    267 	struct vnode *vp;
    268 	int mode;
    269 	struct ucred *cred;
    270 	struct proc *p;
    271 {
    272 	/* if access succeeded, this always does, too */
    273 
    274 	return (0);
    275 }
    276 
    277 /*
    278  * Check mode permission on target pointer. Mode is READ, WRITE or EXEC.
    279  * The mode is shifted to select the owner/group/other fields. The
    280  * super user is granted all permissions.
    281  */
    282 kernfs_access(vp, mode, cred, p)
    283 	struct vnode *vp;
    284 	register int mode;
    285 	struct ucred *cred;
    286 	struct proc *p;
    287 {
    288 	struct kernfs_target *kt = VTOKERN(vp)->kf_kt;
    289 	register gid_t *gp;
    290 	int i, error;
    291 
    292 #ifdef KERN_DIAGNOSTIC
    293 	if (!VOP_ISLOCKED(vp)) {
    294 		vprint("kernfs_access: not locked", vp);
    295 		panic("kernfs_access: not locked");
    296 	}
    297 #endif
    298 	/*
    299 	 * If you're the super-user, you always get access.
    300 	 */
    301 	if (cred->cr_uid == 0)
    302 		return (0);
    303 	/*
    304 	 * Access check is based on only one of owner, group, public.
    305 	 * If not owner, then check group. If not a member of the
    306 	 * group, then check public access.
    307 	 */
    308 	if (cred->cr_uid != /* kt->kt_uid XXX */ 0) {
    309 		mode >>= 3;
    310 		gp = cred->cr_groups;
    311 		for (i = 0; i < cred->cr_ngroups; i++, gp++)
    312 			if (/* kt->kt_gid XXX */ 0 == *gp)
    313 				goto found;
    314 		mode >>= 3;
    315 found:
    316 		;
    317 	}
    318 	if ((kt->kt_perms & mode) == mode)
    319 		return (0);
    320 	return (EACCES);
    321 }
    322 
    323 kernfs_getattr(vp, vap, cred, p)
    324 	struct vnode *vp;
    325 	struct vattr *vap;
    326 	struct ucred *cred;
    327 	struct proc *p;
    328 {
    329 	int error = 0;
    330 	char strbuf[KSTRING];
    331 	struct kernfs_target *kt = VTOKERN(vp)->kf_kt;
    332 
    333 	bzero((caddr_t) vap, sizeof(*vap));
    334 	vattr_null(vap);
    335 	vap->va_uid = kt->kt_uid;
    336 	vap->va_gid = kt->kt_gid;
    337 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
    338 	/* vap->va_qsize = 0; */
    339 	vap->va_blocksize = DEV_BSIZE;
    340 	microtime(&vap->va_atime);
    341 	vap->va_mtime = vap->va_atime;
    342 	vap->va_ctime = vap->va_ctime;
    343 	vap->va_gen = 0;
    344 	vap->va_flags = 0;
    345 	vap->va_rdev = 0;
    346 	/* vap->va_qbytes = 0; */
    347 	vap->va_bytes = 0;
    348 	vap->va_type = kt->kt_vtype;
    349 	vap->va_mode = kt->kt_perms;
    350 
    351 	if (vp->v_flag & VROOT) {
    352 #ifdef KERNFS_DIAGNOSTIC
    353 		printf("kernfs_getattr: stat rootdir\n");
    354 #endif
    355 		vap->va_nlink = 2;
    356 		vap->va_fileid = 2;
    357 		vap->va_size = DEV_BSIZE;
    358 	} else {
    359 #ifdef KERNFS_DIAGNOSTIC
    360 		printf("kernfs_getattr: stat target %s\n", kt->kt_name);
    361 #endif
    362 		vap->va_nlink = 1;
    363 		vap->va_fileid = 3 + (kt - kernfs_targets) / sizeof(*kt);
    364 		error = kernfs_xread(kt, strbuf, sizeof(strbuf), &vap->va_size);
    365 	}
    366 
    367 	vp->v_type = vap->va_type;
    368 #ifdef KERNFS_DIAGNOSTIC
    369 	printf("kernfs_getattr: return error %d\n", error);
    370 #endif
    371 	return (error);
    372 }
    373 
    374 
    375 /*
    376  * Change the mode on a file.
    377  */
    378 kernfs_chmod1(vp, mode, p)
    379 	register struct vnode *vp;
    380 	register int mode;
    381 	struct proc *p;
    382 {
    383 	register struct ucred *cred = p->p_ucred;
    384 	register struct kernfs_target *kt = VTOKERN(vp)->kf_kt;
    385 	int error;
    386 
    387 	if ((mode & kt->kt_maxperms) != mode)	/* can't set ro var to rw */
    388 		return (EPERM);
    389 
    390 	if (cred->cr_uid != kt->kt_uid &&
    391 	    (error = suser(cred, &p->p_acflag)))
    392 		return (error);
    393 	if (cred->cr_uid) {
    394 		if (vp->v_type != VDIR && (mode & S_ISVTX))
    395 			return (EFTYPE);
    396 		if (!groupmember(kt->kt_gid, cred) && (mode & S_ISGID))
    397 			return (EPERM);
    398 	}
    399 	kt->kt_perms &= ~07777;
    400 	kt->kt_perms |= mode & 07777;
    401 /*	ip->i_flag |= ICHG;*/
    402 	return (0);
    403 }
    404 
    405 /*
    406  * Perform chown operation on kernfs_target kt
    407  */
    408 kernfs_chown1(vp, uid, gid, p)
    409 	register struct vnode *vp;
    410 	uid_t uid;
    411 	gid_t gid;
    412 	struct proc *p;
    413 {
    414 	register struct kernfs_target *kt = VTOKERN(vp)->kf_kt;
    415 	register struct ucred *cred = p->p_ucred;
    416 	uid_t ouid;
    417 	gid_t ogid;
    418 	int error = 0;
    419 
    420 	if (uid == (u_short)VNOVAL)
    421 		uid = kt->kt_uid;
    422 	if (gid == (u_short)VNOVAL)
    423 		gid = kt->kt_gid;
    424 	/*
    425 	 * If we don't own the file, are trying to change the owner
    426 	 * of the file, or are not a member of the target group,
    427 	 * the caller must be superuser or the call fails.
    428 	 */
    429 	if ((cred->cr_uid != kt->kt_uid || uid != kt->kt_uid ||
    430 	    !groupmember((gid_t)gid, cred)) &&
    431 	    (error = suser(cred, &p->p_acflag)))
    432 		return (error);
    433 	ouid = kt->kt_uid;
    434 	ogid = kt->kt_gid;
    435 
    436 	kt->kt_uid = uid;
    437 	kt->kt_gid = gid;
    438 
    439 /*	if (ouid != uid || ogid != gid)
    440 		ip->i_flag |= ICHG;*/
    441 	if (ouid != uid && cred->cr_uid != 0)
    442 		kt->kt_perms &= ~S_ISUID;
    443 	if (ogid != gid && cred->cr_uid != 0)
    444 		kt->kt_perms &= ~S_ISGID;
    445 	return (0);
    446 }
    447 
    448 /*
    449  * Set attribute vnode op. called from several syscalls
    450  */
    451 kernfs_setattr(vp, vap, cred, p)
    452 	struct vnode *vp;
    453 	struct vattr *vap;
    454 	struct ucred *cred;
    455 	struct proc *p;
    456 {
    457 	int error = 0;
    458 
    459 	/*
    460 	 * Check for unsetable attributes.
    461 	 */
    462 	if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
    463 	    (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
    464 	    (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
    465 	    ((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
    466 		return (EINVAL);
    467 	}
    468 	/*
    469 	 * Go through the fields and update iff not VNOVAL.
    470 	 */
    471 	if (vap->va_uid != (u_short)VNOVAL || vap->va_gid != (u_short)VNOVAL)
    472 		if (error = kernfs_chown1(vp, vap->va_uid, vap->va_gid, p))
    473 			return (error);
    474 	if (vap->va_size != VNOVAL) {
    475 		if (vp->v_type == VDIR)
    476 			return (EISDIR);
    477 		/* else just nod and smile... */
    478 	}
    479 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
    480 /*		if (cred->cr_uid != ip->i_uid &&
    481 		    (error = suser(cred, &p->p_acflag)))
    482 			return (error);
    483 		if (vap->va_atime.tv_sec != VNOVAL)
    484 			ip->i_flag |= IACC;
    485 		if (vap->va_mtime.tv_sec != VNOVAL)
    486 			ip->i_flag |= IUPD;
    487 		ip->i_flag |= ICHG;
    488 		if (error = iupdat(ip, &vap->va_atime, &vap->va_mtime, 1))
    489 			return (error);
    490 */
    491 	}
    492 	if (vap->va_mode != (u_short)VNOVAL)
    493 		error = kernfs_chmod1(vp, (int)vap->va_mode, p);
    494 	if (vap->va_flags != VNOVAL) {
    495 /*		if (cred->cr_uid != ip->i_uid &&
    496 		    (error = suser(cred, &p->p_acflag)))
    497 			return (error);
    498 		if (cred->cr_uid == 0) {
    499 			ip->i_flags = vap->va_flags;
    500 		} else {
    501 			ip->i_flags &= 0xffff0000;
    502 			ip->i_flags |= (vap->va_flags & 0xffff);
    503 		}
    504 		ip->i_flag |= ICHG;
    505 */
    506 	}
    507 	return (error);
    508 }
    509 
    510 static int
    511 kernfs_read(vp, uio, ioflag, cred)
    512 	struct vnode *vp;
    513 	struct uio *uio;
    514 	int ioflag;
    515 	struct ucred *cred;
    516 {
    517 	struct kernfs_target *kt = VTOKERN(vp)->kf_kt;
    518 	char strbuf[KSTRING];
    519 	int off = uio->uio_offset;
    520 	int len = 0;
    521 	char *cp = strbuf;
    522 	int error;
    523 #ifdef KERNFS_DIAGNOSTIC
    524 	printf("kern_read %s\n", kt->kt_name);
    525 #endif
    526 
    527 	error = kernfs_xread(kt, strbuf, sizeof(strbuf), &len);
    528 	if (error)
    529 		return (error);
    530 	cp = strbuf + off;
    531 	len -= off;
    532 	return (uiomove(cp, len, uio));
    533 }
    534 
    535 static int
    536 kernfs_write(vp, uio, ioflag, cred)
    537 	struct vnode *vp;
    538 	struct uio *uio;
    539 	int ioflag;
    540 	struct ucred *cred;
    541 {
    542 	struct kernfs_target *kt = VTOKERN(vp)->kf_kt;
    543 	char strbuf[KSTRING];
    544 	int len = uio->uio_resid;
    545 	char *cp = strbuf;
    546 	int xlen;
    547 	int error;
    548 
    549 	if (uio->uio_offset != 0)
    550 		return (EINVAL);
    551 
    552 	xlen = min(uio->uio_resid, KSTRING-1);
    553 	error = uiomove(strbuf, xlen, uio);
    554 	if (error)
    555 		return (error);
    556 
    557 	if (uio->uio_resid != 0)
    558 		return (EIO);
    559 
    560 	strbuf[xlen] = '\0';
    561 	return (kernfs_xwrite(kt, strbuf, xlen));
    562 }
    563 
    564 kernfs_readdir(vp, uio, cred, eofflagp, cookies, ncookies)
    565 	struct vnode *vp;
    566 	struct uio *uio;
    567 	struct ucred *cred;
    568 	int *eofflagp;
    569 	u_int *cookies;
    570 	int ncookies;
    571 {
    572 	struct filedesc *fdp;
    573 	int i;
    574 	int error;
    575 
    576 	i = uio->uio_offset / UIO_MX;
    577 	error = 0;
    578 	while (uio->uio_resid > 0 && (!cookies || ncookies > 0)) {
    579 #ifdef KERNFS_DIAGNOSTIC
    580 		printf("kernfs_readdir: i = %d\n", i);
    581 #endif
    582 		if (i >= nkernfs_targets) {
    583 			*eofflagp = 1;
    584 			break;
    585 		}
    586 		{
    587 			struct direct d;
    588 			struct direct *dp = &d;
    589 			struct kernfs_target *kt = &kernfs_targets[i];
    590 
    591 			bzero((caddr_t) dp, UIO_MX);
    592 
    593 			dp->d_namlen = strlen(kt->kt_name);
    594 			bcopy(kt->kt_name, dp->d_name, dp->d_namlen+1);
    595 
    596 #ifdef KERNFS_DIAGNOSTIC
    597 			printf("kernfs_readdir: name = %s, len = %d\n",
    598 					dp->d_name, dp->d_namlen);
    599 #endif
    600 			/*
    601 			 * Fill in the remaining fields
    602 			 */
    603 			dp->d_reclen = UIO_MX;
    604 			dp->d_ino = i + 3;
    605 			/*
    606 			 * And ship to userland
    607 			 */
    608 			error = uiomove((caddr_t) dp, UIO_MX, uio);
    609 			if (error)
    610 				break;
    611 			if (cookies) {
    612 				*cookies = (i + 1) * UIO_MX;
    613 				ncookies--;
    614 			}
    615 		}
    616 		i++;
    617 	}
    618 
    619 	uio->uio_offset = i * UIO_MX;
    620 
    621 	return (error);
    622 }
    623 
    624 kernfs_inactive(vp, p)
    625 	struct vnode *vp;
    626 	struct proc *p;
    627 {
    628 	/*
    629 	 * Clear out the v_type field to avoid
    630 	 * nasty things happening in vgone().
    631 	 */
    632 	vp->v_type = VNON;
    633 #ifdef KERNFS_DIAGNOSTIC
    634 	printf("kernfs_inactive(%x)\n", vp);
    635 #endif
    636 	return (0);
    637 }
    638 
    639 /*
    640  * Print out the contents of a kernfs vnode.
    641  */
    642 /* ARGSUSED */
    643 void
    644 kernfs_print(vp)
    645 	struct vnode *vp;
    646 {
    647 	printf("tag VT_KERNFS, kernfs vnode\n");
    648 }
    649 
    650 /*
    651  * kernfs vnode unsupported operation
    652  */
    653 kernfs_enotsupp()
    654 {
    655 	return (EOPNOTSUPP);
    656 }
    657 
    658 /*
    659  * kernfs "should never get here" operation
    660  */
    661 kernfs_badop()
    662 {
    663 	panic("kernfs: bad op");
    664 	/* NOTREACHED */
    665 }
    666 
    667 /*
    668  * kernfs vnode null operation
    669  */
    670 kernfs_nullop()
    671 {
    672 	return (0);
    673 }
    674 
    675 #define kernfs_create ((int (*) __P(( \
    676 		struct nameidata *ndp, \
    677 		struct vattr *vap, \
    678 		struct proc *p))) kernfs_enotsupp)
    679 #define kernfs_mknod ((int (*) __P(( \
    680 		struct nameidata *ndp, \
    681 		struct vattr *vap, \
    682 		struct ucred *cred, \
    683 		struct proc *p))) kernfs_enotsupp)
    684 #define kernfs_close ((int (*) __P(( \
    685 		struct vnode *vp, \
    686 		int fflag, \
    687 		struct ucred *cred, \
    688 		struct proc *p))) nullop)
    689 #define	kernfs_ioctl ((int (*) __P(( \
    690 		struct vnode *vp, \
    691 		int command, \
    692 		caddr_t data, \
    693 		int fflag, \
    694 		struct ucred *cred, \
    695 		struct proc *p))) kernfs_enotsupp)
    696 #define	kernfs_select ((int (*) __P(( \
    697 		struct vnode *vp, \
    698 		int which, \
    699 		int fflags, \
    700 		struct ucred *cred, \
    701 		struct proc *p))) kernfs_enotsupp)
    702 #define kernfs_mmap ((int (*) __P(( \
    703 		struct vnode *vp, \
    704 		int fflags, \
    705 		struct ucred *cred, \
    706 		struct proc *p))) kernfs_enotsupp)
    707 #define kernfs_fsync ((int (*) __P(( \
    708 		struct vnode *vp, \
    709 		int fflags, \
    710 		struct ucred *cred, \
    711 		int waitfor, \
    712 		struct proc *p))) nullop)
    713 #define kernfs_seek ((int (*) __P(( \
    714 		struct vnode *vp, \
    715 		off_t oldoff, \
    716 		off_t newoff, \
    717 		struct ucred *cred))) nullop)
    718 #define kernfs_remove ((int (*) __P(( \
    719 		struct nameidata *ndp, \
    720 		struct proc *p))) kernfs_enotsupp)
    721 #define kernfs_link ((int (*) __P(( \
    722 		struct vnode *vp, \
    723 		struct nameidata *ndp, \
    724 		struct proc *p))) kernfs_enotsupp)
    725 #define kernfs_rename ((int (*) __P(( \
    726 		struct nameidata *fndp, \
    727 		struct nameidata *tdnp, \
    728 		struct proc *p))) kernfs_enotsupp)
    729 #define kernfs_mkdir ((int (*) __P(( \
    730 		struct nameidata *ndp, \
    731 		struct vattr *vap, \
    732 		struct proc *p))) kernfs_enotsupp)
    733 #define kernfs_rmdir ((int (*) __P(( \
    734 		struct nameidata *ndp, \
    735 		struct proc *p))) kernfs_enotsupp)
    736 #define kernfs_symlink ((int (*) __P(( \
    737 		struct nameidata *ndp, \
    738 		struct vattr *vap, \
    739 		char *target, \
    740 		struct proc *p))) kernfs_enotsupp)
    741 #define kernfs_readlink ((int (*) __P(( \
    742 		struct vnode *vp, \
    743 		struct uio *uio, \
    744 		struct ucred *cred))) kernfs_enotsupp)
    745 #define kernfs_abortop ((int (*) __P(( \
    746 		struct nameidata *ndp))) nullop)
    747 #ifdef KERNFS_DIAGNOSTIC
    748 int kernfs_reclaim(vp)
    749 struct vnode *vp;
    750 {
    751 	printf("kernfs_reclaim(%x)\n", vp);
    752 	return (0);
    753 }
    754 #else
    755 #define kernfs_reclaim ((int (*) __P(( \
    756 		struct vnode *vp))) nullop)
    757 #endif
    758 #define	kernfs_lock ((int (*) __P(( \
    759 		struct vnode *vp))) nullop)
    760 #define kernfs_unlock ((int (*) __P(( \
    761 		struct vnode *vp))) nullop)
    762 #define	kernfs_bmap ((int (*) __P(( \
    763 		struct vnode *vp, \
    764 		daddr_t bn, \
    765 		struct vnode **vpp, \
    766 		daddr_t *bnp))) kernfs_badop)
    767 #define	kernfs_strategy ((int (*) __P(( \
    768 		struct buf *bp))) kernfs_badop)
    769 #define kernfs_islocked ((int (*) __P(( \
    770 		struct vnode *vp))) nullop)
    771 #define kernfs_advlock ((int (*) __P(( \
    772 		struct vnode *vp, \
    773 		caddr_t id, \
    774 		int op, \
    775 		struct flock *fl, \
    776 		int flags))) kernfs_enotsupp)
    777 
    778 struct vnodeops kernfs_vnodeops = {
    779 	kernfs_lookup,	/* lookup */
    780 	kernfs_create,	/* create */
    781 	kernfs_mknod,	/* mknod */
    782 	kernfs_open,	/* open */
    783 	kernfs_close,	/* close */
    784 	kernfs_access,	/* access */
    785 	kernfs_getattr,	/* getattr */
    786 	kernfs_setattr,	/* setattr */
    787 	kernfs_read,	/* read */
    788 	kernfs_write,	/* write */
    789 	kernfs_ioctl,	/* ioctl */
    790 	kernfs_select,	/* select */
    791 	kernfs_mmap,	/* mmap */
    792 	kernfs_fsync,	/* fsync */
    793 	kernfs_seek,	/* seek */
    794 	kernfs_remove,	/* remove */
    795 	kernfs_link,	/* link */
    796 	kernfs_rename,	/* rename */
    797 	kernfs_mkdir,	/* mkdir */
    798 	kernfs_rmdir,	/* rmdir */
    799 	kernfs_symlink,	/* symlink */
    800 	kernfs_readdir,	/* readdir */
    801 	kernfs_readlink,	/* readlink */
    802 	kernfs_abortop,	/* abortop */
    803 	kernfs_inactive,	/* inactive */
    804 	kernfs_reclaim,	/* reclaim */
    805 	kernfs_lock,	/* lock */
    806 	kernfs_unlock,	/* unlock */
    807 	kernfs_bmap,	/* bmap */
    808 	kernfs_strategy,	/* strategy */
    809 	kernfs_print,	/* print */
    810 	kernfs_islocked,	/* islocked */
    811 	kernfs_advlock,	/* advlock */
    812 };
    813