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procfs_vnops.c revision 1.8 
      1 /*
      2  * Copyright (c) 1993 Paul Kranenburg
      3  * All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *      This product includes software developed by Paul Kranenburg.
     16  * 4. The name of the author may not be used to endorse or promote products
     17  *    derived from this software withough specific prior written permission
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  *
     30  *	$Id: procfs_vnops.c,v 1.8 1993/12/18 03:58:14 mycroft Exp $
     31  */
     32 
     33 /*
     34  * PROCFS vnode interface routines
     35  */
     36 
     37 #include <sys/param.h>
     38 #include <sys/systm.h>
     39 #include <sys/time.h>
     40 #include <sys/kernel.h>
     41 #include <sys/ioctl.h>
     42 #include <sys/file.h>
     43 #include <sys/proc.h>
     44 #include <sys/buf.h>
     45 #include <sys/vnode.h>
     46 #include <sys/namei.h>
     47 #include <sys/resourcevar.h>
     48 #include <vm/vm.h>
     49 #include <sys/kinfo.h>
     50 #include <sys/kinfo_proc.h>
     51 
     52 #include <sys/procfs.h>
     53 #include <miscfs/procfs/pfsnode.h>
     54 
     55 #include <machine/vmparam.h>
     56 
     57 /*
     58  * procfs vnode operations.
     59  */
     60 struct vnodeops pfs_vnodeops = {
     61 	pfs_lookup,		/* lookup */
     62 	pfs_create,		/* create */
     63 	pfs_mknod,		/* mknod */
     64 	pfs_open,		/* open */
     65 	pfs_close,		/* close */
     66 	pfs_access,		/* access */
     67 	pfs_getattr,		/* getattr */
     68 	pfs_setattr,		/* setattr */
     69 	pfs_read,		/* read */
     70 	pfs_write,		/* write */
     71 	pfs_ioctl,		/* ioctl */
     72 	pfs_select,		/* select */
     73 	pfs_mmap,		/* mmap */
     74 	pfs_fsync,		/* fsync */
     75 	pfs_seek,		/* seek */
     76 	pfs_remove,		/* remove */
     77 	pfs_link,		/* link */
     78 	pfs_rename,		/* rename */
     79 	pfs_mkdir,		/* mkdir */
     80 	pfs_rmdir,		/* rmdir */
     81 	pfs_symlink,		/* symlink */
     82 	pfs_readdir,		/* readdir */
     83 	pfs_readlink,		/* readlink */
     84 	pfs_abortop,		/* abortop */
     85 	pfs_inactive,		/* inactive */
     86 	pfs_reclaim,		/* reclaim */
     87 	pfs_lock,		/* lock */
     88 	pfs_unlock,		/* unlock */
     89 	pfs_bmap,		/* bmap */
     90 	pfs_strategy,		/* strategy */
     91 	pfs_print,		/* print */
     92 	pfs_islocked,		/* islocked */
     93 	pfs_advlock,		/* advlock */
     94 };
     95 
     96 /*
     97  * Vnode Operations.
     98  *
     99  */
    100 /* ARGSUSED */
    101 int
    102 pfs_open(vp, mode, cred, p)
    103 	register struct vnode *vp;
    104 	int mode;
    105 	struct ucred *cred;
    106 	struct proc *p;
    107 {
    108 	struct pfsnode	*pfsp = VTOPFS(vp);
    109 
    110 #ifdef DEBUG
    111 	if (pfs_debug)
    112 		printf("pfs_open: vp 0x%x, proc %d\n", vp, p->p_pid);
    113 #endif
    114 
    115 	if ((pfsp->pfs_pid?pfind(pfsp->pfs_pid):&proc0) == NULL)
    116 		return ESRCH;
    117 
    118 	if (	(pfsp->pfs_flags & FWRITE) && (mode & O_EXCL) ||
    119 		(pfsp->pfs_flags & O_EXCL) && (mode & FWRITE)	)
    120 		return EBUSY;
    121 
    122 
    123 	if (mode & FWRITE)
    124 		pfsp->pfs_flags = (mode & (FWRITE|O_EXCL));
    125 	return 0;
    126 }
    127 
    128 /*
    129  * /proc filesystem close routine
    130  */
    131 /* ARGSUSED */
    132 int
    133 pfs_close(vp, flag, cred, p)
    134 	register struct vnode *vp;
    135 	int flag;
    136 	struct ucred *cred;
    137 	struct proc *p;
    138 {
    139 	struct pfsnode	*pfsp = VTOPFS(vp);
    140 
    141 #ifdef DEBUG
    142 	if (pfs_debug)
    143 		printf("pfs_close: vp 0x%x proc %d\n", vp, p->p_pid);
    144 #endif
    145 	if ((flag & FWRITE) && (pfsp->pfs_flags & O_EXCL))
    146 		pfsp->pfs_flags &= ~(FWRITE|O_EXCL);
    147 
    148 	return (0);
    149 }
    150 
    151 /*
    152  * Ioctl operation.
    153  */
    154 /* ARGSUSED */
    155 int
    156 pfs_ioctl(vp, com, data, fflag, cred, p)
    157 	struct vnode *vp;
    158 	int com;
    159 	caddr_t data;
    160 	int fflag;
    161 	struct ucred *cred;
    162 	struct proc *p;
    163 {
    164 	int		error = 0;
    165 	struct proc	*procp;
    166 	struct pfsnode	*pfsp = VTOPFS(vp);
    167 
    168 	procp = pfsp->pfs_pid?pfind(pfsp->pfs_pid):&proc0;
    169 	if (!procp)
    170 		return ESRCH;
    171 
    172 	switch (com) {
    173 
    174 	case PIOCGPINFO: {
    175 		int copysize = sizeof(struct kinfo_proc), needed;
    176 		kinfo_doproc(KINFO_PROC_PID, data, &copysize,
    177 						pfsp->pfs_pid, &needed);
    178 		break;
    179 		}
    180 
    181 #ifdef notyet /* Changes to proc.h needed */
    182 	case PIOCGSIGSET:
    183 		procp->p_psigset = *(sigset_t *)data;
    184 		break;
    185 
    186 	case PIOCSSIGSET:
    187 		*(sigset_t *)data = procp->p_psigset;
    188 		break;
    189 
    190 	case PIOCGFLTSET:
    191 		procp->p_pfltset = *(sigflt_t *)data;
    192 		break;
    193 
    194 	case PIOCSFLTSET:
    195 		*(fltset_t *)data = procp->p_pfltset;
    196 		break;
    197 #endif
    198 
    199 	case PIOCGMAPFD:
    200 		error = pfs_vmfd(procp, pfsp, (struct vmfd *)data, p);
    201 		break;
    202 
    203 	case PIOCGNMAP:
    204 		*(int *)data = pfs_vm_nentries(procp, pfsp);
    205 		break;
    206 
    207 	case PIOCGMAP:
    208 		error = pfs_vmmap(procp, pfsp, *(struct procmap *)data);
    209 		break;
    210 
    211 	default:
    212 		error = EIO;
    213 		break;
    214 	}
    215 	return error;
    216 }
    217 
    218 /*
    219  * Pass I/O requests to the memory filesystem process.
    220  */
    221 int
    222 pfs_strategy(bp)
    223 	register struct buf *bp;
    224 {
    225 	struct vnode *vp;
    226 	struct proc *p = curproc;		/* XXX */
    227 
    228 	return (0);
    229 }
    230 
    231 /*
    232  * This is a noop, simply returning what one has been given.
    233  */
    234 int
    235 pfs_bmap(vp, bn, vpp, bnp)
    236 	struct vnode *vp;
    237 	daddr_t bn;
    238 	struct vnode **vpp;
    239 	daddr_t *bnp;
    240 {
    241 
    242 	if (vpp != NULL)
    243 		*vpp = vp;
    244 	if (bnp != NULL)
    245 		*bnp = bn;
    246 	return (0);
    247 }
    248 
    249 /*
    250  * /proc filesystem inactive routine
    251  */
    252 /* ARGSUSED */
    253 int
    254 pfs_inactive(vp, p)
    255 	struct vnode *vp;
    256 	struct proc *p;
    257 {
    258 	struct pfsnode	*pfsp = VTOPFS(vp);
    259 
    260 	if ((pfsp->pfs_pid?pfind(pfsp->pfs_pid):&proc0) == NULL
    261 			&& vp->v_usecount == 0)
    262 		vgone(vp);
    263 
    264 	return 0;
    265 }
    266 
    267 /*
    268  * /proc filesystem reclaim routine
    269  */
    270 /* ARGSUSED */
    271 int
    272 pfs_reclaim(vp)
    273 	struct vnode *vp;
    274 {
    275 	struct pfsnode	**pp, *pfsp = VTOPFS(vp);
    276 
    277 	for (pp = &pfshead; *pp; pp = &(*pp)->pfs_next) {
    278 		if (*pp == pfsp) {
    279 			*pp = pfsp->pfs_next;
    280 			break;
    281 		}
    282 	}
    283 	return 0;
    284 }
    285 
    286 /*
    287  * Print out the contents of an pfsnode.
    288  */
    289 void
    290 pfs_print(vp)
    291 	struct vnode *vp;
    292 {
    293 	struct pfsnode	*pfsp = VTOPFS(vp);
    294 
    295 	printf("tag VT_PROCFS, pid %d, uid %d, gid %d, mode %x, flags %x\n",
    296 		pfsp->pfs_pid,
    297 		pfsp->pfs_uid, pfsp->pfs_gid,
    298 		pfsp->pfs_mode, pfsp->pfs_flags);
    299 
    300 	return;
    301 }
    302 
    303 /*
    304  * /proc bad operation
    305  */
    306 int
    307 pfs_badop()
    308 {
    309 	printf("pfs_badop called\n");
    310 	return EIO;
    311 }
    312 
    313 #if 0 /* Moved to pfs_subr.c */
    314 /*
    315  * Vnode op for reading/writing.
    316  */
    317 /* ARGSUSED */
    318 int
    319 pfs_doio(vp, uio, ioflag, cred)
    320 	struct vnode *vp;
    321 	register struct uio *uio;
    322 	int ioflag;
    323 	struct ucred *cred;
    324 {
    325 	struct pfsnode	*pfsp = VTOPFS(vp);
    326 	struct proc	*procp;
    327 	int		error = 0;
    328 	long		n, off;
    329 	caddr_t		kva;
    330 
    331 #ifdef DEBUG
    332 	if (pfs_debug)
    333 		printf("pfs_doio(%s): vp 0x%x, proc %x\n",
    334 			uio->uio_rw==UIO_READ?"R":"W", vp, uio->uio_procp);
    335 #endif
    336 
    337 #ifdef DIAGNOSTIC
    338 	if (vp->v_type != VPROC)
    339 		panic("pfs_doio vtype");
    340 #endif
    341 	procp = pfsp->pfs_pid?pfind(pfsp->pfs_pid):&proc0;
    342 	if (!procp)
    343 		return ESRCH;
    344 
    345 	if (uio->uio_resid == 0)
    346 		return (0);
    347 	if (uio->uio_offset < 0)
    348 		return (EINVAL);
    349 
    350 	do { /* One page at a time */
    351 		off = uio->uio_offset - trunc_page(uio->uio_offset);
    352 		n = MIN(PAGE_SIZE-off, uio->uio_resid);
    353 
    354 		/* Map page into kernel space */
    355 		error = pfs_map(procp, &kva, uio->uio_rw, uio->uio_offset);
    356 		if (error)
    357 			return error;
    358 
    359 		error = uiomove(kva + off, (int)n, uio);
    360 		pfs_unmap(procp, kva);
    361 
    362 	} while (error == 0 && uio->uio_resid > 0);
    363 
    364 	return (error);
    365 }
    366 #endif
    367 
    368 /*
    369  * Make up some attributes for a process file
    370  */
    371 int
    372 pfs_getattr (vp, vap, cred, p)
    373 	struct vnode *vp;
    374 	struct vattr *vap;
    375 	struct ucred *cred;
    376 	struct proc *p;
    377 {
    378 	struct pfsnode *pfsp = VTOPFS(vp);
    379 	struct proc *procp;
    380 
    381 	VATTR_NULL(vap);
    382 	vap->va_type = vp->v_type;
    383 	vap->va_mode = pfsp->pfs_mode;
    384 	vap->va_flags = pfsp->pfs_vflags;
    385 
    386 	if (vp->v_flag & VROOT) {
    387 		vap->va_nlink = 2;
    388 		vap->va_size =
    389 			roundup((2+nprocs)*sizeof(struct pfsdent), DIRBLKSIZ);
    390 		vap->va_size_rsv = 0;
    391 		vap->va_uid = pfsp->pfs_uid;
    392 		vap->va_gid = pfsp->pfs_gid;
    393 		vap->va_atime = vap->va_mtime = vap->va_ctime = time; /*XXX*/
    394 		return 0;
    395 	}
    396 
    397 	procp = pfsp->pfs_pid?pfind(pfsp->pfs_pid):&proc0;
    398 	if (!procp)
    399 		return ESRCH;
    400 
    401 	vap->va_nlink = 1;
    402 	vap->va_size = ctob(	procp->p_vmspace->vm_tsize +
    403 				procp->p_vmspace->vm_dsize +
    404 				procp->p_vmspace->vm_ssize);
    405 	vap->va_size_rsv = 0;
    406 	vap->va_blocksize = page_size;
    407 	vap->va_uid = procp->p_ucred->cr_uid;
    408 	vap->va_gid = procp->p_ucred->cr_gid;
    409 	if (vap->va_uid != procp->p_cred->p_ruid)
    410 		vap->va_mode |= VSUID;
    411 	if (vap->va_gid != procp->p_cred->p_rgid)
    412 		vap->va_mode |= VSGID;
    413 	if (procp->p_flag & SLOAD) {
    414 		vap->va_atime = vap->va_mtime = vap->va_ctime =
    415 			procp->p_stats->p_start;
    416 	}
    417 
    418 	return 0;
    419 }
    420 
    421 /*
    422  * Set some attributes for a process file
    423  */
    424 int
    425 pfs_setattr (vp, vap, cred, p)
    426 	struct vnode *vp;
    427 	struct vattr *vap;
    428 	struct ucred *cred;
    429 	struct proc *p;
    430 {
    431 	struct pfsnode *pfsp = VTOPFS(vp);
    432 	struct proc *procp;
    433 	int error = 0;
    434 
    435 	procp = pfsp->pfs_pid?pfind(pfsp->pfs_pid):&proc0;
    436 		if (!procp)
    437 			return ESRCH;
    438 
    439 	/*
    440 	 * Check for unsetable attributes.
    441 	 */
    442 	if ((vap->va_type != VNON) || (vap->va_nlink != (short)VNOVAL) ||
    443 	    (vap->va_fsid != (long)VNOVAL) ||
    444 	    (vap->va_fileid != (long)VNOVAL) ||
    445 	    (vap->va_blocksize != (long)VNOVAL) ||
    446 	    (vap->va_rdev != (dev_t)VNOVAL) ||
    447 	    ((int)vap->va_bytes != (u_long)VNOVAL) ||
    448 	    ((int)vap->va_bytes_rsv != (u_long)VNOVAL) ||
    449 	    ((int)vap->va_size != (u_long)VNOVAL) ||
    450 	    ((int)vap->va_size_rsv != (u_long)VNOVAL) ||
    451 	    (vap->va_gen != (long)VNOVAL) ||
    452 	    ((int)vap->va_atime.tv_sec != (u_long)VNOVAL) ||
    453 	    ((int)vap->va_mtime.tv_sec != (u_long)VNOVAL) ||
    454 	    ((int)vap->va_ctime.tv_sec != (u_long)VNOVAL) ||
    455 	    ((	(vap->va_uid != (uid_t)VNOVAL) ||
    456 		(vap->va_gid != (gid_t)VNOVAL)) && !(vp->v_flag & VROOT)) ) {
    457 		return (EINVAL);
    458 	}
    459 
    460 	/* set mode bits, only rwx bits are modified */
    461 	if (vap->va_mode != (u_short)VNOVAL) {
    462 		if (cred->cr_uid != pfsp->pfs_uid &&
    463 			(error = suser(cred, &p->p_acflag)))
    464 				return (error);
    465 		pfsp->pfs_mode = vap->va_mode & 0777;
    466 	}
    467 
    468 	/* For now, only allow to change ownership of "/proc" itself */
    469 	if ((vp->v_flag & VROOT) && vap->va_uid != (uid_t)VNOVAL) {
    470 		if ((error = suser(cred, &p->p_acflag)))
    471 			return (error);
    472 		pfsp->pfs_uid = vap->va_uid;
    473 	}
    474 
    475 	if ((vp->v_flag & VROOT) && vap->va_gid != (gid_t)VNOVAL) {
    476 		if ((cred->cr_uid != pfsp->pfs_uid ||
    477 			!groupmember(vap->va_gid, cred)) &&
    478 				(error = suser(cred, &p->p_acflag)))
    479 			return error;
    480 
    481 		pfsp->pfs_gid = vap->va_gid;
    482 	}
    483 
    484 	/* chflags() */
    485 	if (vap->va_flags != (u_long)VNOVAL) {
    486 		if (cred->cr_uid != pfsp->pfs_uid &&
    487 			(error = suser(cred, &p->p_acflag)))
    488 				return (error);
    489 		if (cred->cr_uid == 0) {
    490 			pfsp->pfs_vflags = vap->va_flags;
    491 		} else {
    492 			pfsp->pfs_vflags &= 0xffff0000;
    493 			pfsp->pfs_vflags |= (vap->va_flags & 0xffff);
    494 		}
    495 	}
    496 	return 0;
    497 }
    498 
    499 int
    500 pfs_access (vp, mode, cred, p)
    501 	struct vnode *vp;
    502 	int mode;
    503 	struct ucred *cred;
    504 	struct proc *p;
    505 {
    506 	register struct vattr *vap;
    507 	register gid_t *gp;
    508 	struct vattr vattr;
    509 	register int i;
    510 	int error;
    511 
    512 	/*
    513 	 * If you're the super-user,
    514 	 * you always get access.
    515 	 */
    516 	if (cred->cr_uid == (uid_t)0)
    517 		return (0);
    518 	vap = &vattr;
    519 	if (error = pfs_getattr(vp, vap, cred, p))
    520 		return (error);
    521 	/*
    522 	 * Access check is based on only one of owner, group, public.
    523 	 * If not owner, then check group. If not a member of the
    524 	 * group, then check public access.
    525 	 */
    526 	if (cred->cr_uid != vap->va_uid) {
    527 		mode >>= 3;
    528 		gp = cred->cr_groups;
    529 		for (i = 0; i < cred->cr_ngroups; i++, gp++)
    530 			if (vap->va_gid == *gp)
    531 				goto found;
    532 		mode >>= 3;
    533 found:
    534 		;
    535 	}
    536 	if ((vap->va_mode & mode) != 0)
    537 		return (0);
    538 	return (EACCES);
    539 }
    540 
    541 /*
    542  * /proc lookup
    543  */
    544 int
    545 pfs_lookup(vp, ndp, p)
    546 	register struct vnode *vp;
    547 	register struct nameidata *ndp;
    548 	struct proc *p;
    549 {
    550 	int lockparent, wantparent, flag, error = 0;
    551 	pid_t pid;
    552 	struct vnode *nvp;
    553 	struct pfsnode *pfsp;
    554 	struct proc *procp;
    555 
    556 #ifdef DEBUG
    557 	if (pfs_debug)
    558 		printf("pfs_lookup: vp 0x%x name %s proc %d\n",
    559 			vp, ndp->ni_ptr, p->p_pid);
    560 #endif
    561 
    562 	ndp->ni_dvp = vp;
    563 	ndp->ni_vp = NULL;
    564 	if (vp->v_type != VDIR)
    565 		return (ENOTDIR);
    566 
    567 	lockparent = ndp->ni_nameiop & LOCKPARENT;
    568 	flag = ndp->ni_nameiop & OPMASK;
    569 	wantparent = ndp->ni_nameiop & (LOCKPARENT|WANTPARENT);
    570 	if (flag != LOOKUP)
    571 		return EACCES;
    572 	if (ndp->ni_isdotdot) {
    573 		/* Should not happen */
    574 		printf("pfs_lookup: vp 0x%x: dotdot\n", vp);
    575 		return EIO;
    576 	}
    577 	if (ndp->ni_namelen == 1 && *ndp->ni_ptr == '.') {
    578 		VREF(vp);
    579 		ndp->ni_vp = vp;
    580 		return 0;
    581 	}
    582 
    583 	pid = (pid_t)atoi(ndp->ni_ptr, ndp->ni_namelen);
    584 	if (pid == (pid_t)-1)
    585 		return ENOENT;
    586 
    587 	if ((procp = pid?pfind(pid):&proc0) == NULL)
    588 		return ENOENT;
    589 
    590 	/* Search pfs node list first */
    591 	for (pfsp = pfshead; pfsp != NULL; pfsp = pfsp->pfs_next) {
    592 		if (pfsp->pfs_pid == pid)
    593 			break;
    594 	}
    595 
    596 	if (pfsp == NULL) {
    597 		struct pfsnode	**pp;
    598 		error = getnewvnode(VT_PROCFS, vp->v_mount, &pfs_vnodeops, &nvp);
    599 		if (error)
    600 			return error;
    601 
    602 		nvp->v_type = VPROC;
    603 		pfsp = VTOPFS(nvp);
    604 		pfsp->pfs_next = NULL;
    605 		pfsp->pfs_pid = pid;
    606 		pfsp->pfs_vnode = nvp;
    607 		pfsp->pfs_flags = 0;
    608 		pfsp->pfs_vflags = 0;
    609 		pfsp->pfs_uid = procp->p_ucred->cr_uid;
    610 		pfsp->pfs_gid = procp->p_ucred->cr_gid;
    611 		pfsp->pfs_mode = 0700;	/* Initial access bits */
    612 
    613 		/* Append to pfs node list */
    614 		for (pp = &pfshead; *pp; pp = &(*pp)->pfs_next);
    615 		*pp = pfsp;
    616 
    617 	}
    618 	ndp->ni_vp = pfsp->pfs_vnode;
    619 
    620 	return (error);
    621 }
    622 
    623 int
    624 pfs_readdir(vp, uio, cred, eofflagp, cookies, ncookies)
    625         struct vnode *vp;
    626         register struct uio *uio;
    627         struct ucred *cred;
    628         int *eofflagp;
    629 	u_int *cookies;
    630 	int ncookies;
    631 {
    632 	int	error = 0;
    633 	int	count, lost, pcnt, skipcnt, doingzomb = 0;
    634 	struct proc *p;
    635 	struct pfsdent dent;
    636 
    637 #ifdef DEBUG
    638 	if (pfs_debug)
    639 		printf("pfs_readdir: vp 0x%x proc %d\n",
    640 				vp, uio->uio_procp->p_pid);
    641 #endif
    642 	count = uio->uio_resid;
    643 	count &= ~(DIRBLKSIZ - 1);
    644 	lost = uio->uio_resid - count;
    645 	if (count < DIRBLKSIZ || (uio->uio_offset & (DIRBLKSIZ -1)))
    646 		return (EINVAL);
    647 	uio->uio_resid = count;
    648 	uio->uio_iov->iov_len = count;
    649 	*eofflagp = 1;
    650 	skipcnt = uio->uio_offset / sizeof(struct pfsdent);
    651 
    652 	count = 0;
    653 	if (skipcnt == 0) {
    654 		/* Fake "." and ".." entries? */
    655 #if 1
    656 		dent.d_fileno = 2;		/* XXX - Filesystem root */
    657 		dent.d_reclen = sizeof(struct pfsdent);
    658 
    659 		dent.d_namlen = 1;
    660 		dent.d_nam[0] = '.';
    661 		dent.d_nam[1] = '\0';
    662 		error = uiomove((char *)&dent, sizeof(struct pfsdent) , uio);
    663 		if (error)
    664 			return error;
    665 		if (cookies) {
    666 			*cookies++ = sizeof(struct pfsdent);
    667 			ncookies--;
    668 		}
    669 
    670 		dent.d_fileno = 2;
    671 		dent.d_namlen = 2;
    672 		dent.d_nam[1] = '.';
    673 		dent.d_nam[2] = '\0';
    674 		error = uiomove((char *)&dent, sizeof(struct pfsdent) , uio);
    675 		if (error)
    676 			return error;
    677 		if (cookies) {
    678 			*cookies++ = 2 * sizeof(struct pfsdent);
    679 			ncookies--;
    680 		}
    681 #endif
    682 		count += 2*dent.d_reclen;
    683 	}
    684 
    685 	p = (struct proc *)allproc;
    686 	for (pcnt = 0; p && uio->uio_resid && (!cookies || ncookies > 0); pcnt++) {
    687 		if (pcnt < skipcnt) {
    688 			p = p->p_nxt;
    689 			if (p == NULL && doingzomb == 0) {
    690 				doingzomb = 1;
    691 				p = zombproc;
    692 			}
    693 			continue;
    694 		}
    695 		*eofflagp = 0;
    696 
    697 		/* "inode" is process slot (actually position on list) */
    698 		dent.d_fileno = (unsigned long)(pcnt+1);
    699 		dent.d_namlen = itos((unsigned int)p->p_pid, dent.d_nam);
    700 		dent.d_nam[dent.d_namlen] = '\0';
    701 
    702 		p = p->p_nxt;
    703 		if (p == NULL && doingzomb == 0) {
    704 			doingzomb = 1;
    705 			p = zombproc;
    706 		}
    707 		if (p == NULL) {
    708 			/* Extend 'reclen' to end of block */;
    709 			dent.d_reclen = DIRBLKSIZ - (count & (DIRBLKSIZ - 1));
    710 		} else
    711 			dent.d_reclen = sizeof(struct pfsdent);
    712 		count += dent.d_reclen;
    713 		error = uiomove((char *)&dent, dent.d_reclen, uio);
    714 		if (error)
    715 			break;
    716 		if (cookies) {
    717 			*cookies++ = count;
    718 			ncookies--;
    719 		}
    720 	}
    721 	if (count == 0)
    722 		*eofflagp = 1;
    723 
    724 	uio->uio_resid += lost;
    725 	return error;
    726 }
    727 
    728 /*
    729  * convert n to decimal representation in character array b
    730  * return number of decimal digits produced.
    731  */
    732 int
    733 itos(n, b)
    734 unsigned int n;
    735 char *b;
    736 {
    737 #define BASE	10
    738 	int m = (n<BASE)?0:itos(n/BASE, b);
    739 
    740 	*(b+m) = "0123456789abcdef"[n%BASE];
    741 	return m+1;
    742 }
    743 
    744 /*
    745  * convert decimal ascii representation in b of length len to integer
    746  */
    747 int
    748 atoi(b, len)
    749 char *b;
    750 unsigned int len;
    751 {
    752 	int n = 0;
    753 
    754 	while (len--) {
    755 		register char c = *b++;
    756 		if (c < '0' || c > '9')
    757 			return -1;
    758 		n = 10 * n + (c - '0');
    759 	}
    760 	return n;
    761 }
    762