xref: /netbsd-src/sys/miscfs/procfs/procfs_subr.c (revision 5bbd2a12505d72a8177929a37b5cee489d0a1cfd)
1 /*	$NetBSD: procfs_subr.c,v 1.101 2012/05/28 13:16:10 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * This code is derived from software contributed to Berkeley by
37  * Jan-Simon Pendry.
38  *
39  * Redistribution and use in source and binary forms, with or without
40  * modification, are permitted provided that the following conditions
41  * are met:
42  * 1. Redistributions of source code must retain the above copyright
43  *    notice, this list of conditions and the following disclaimer.
44  * 2. Redistributions in binary form must reproduce the above copyright
45  *    notice, this list of conditions and the following disclaimer in the
46  *    documentation and/or other materials provided with the distribution.
47  * 3. Neither the name of the University nor the names of its contributors
48  *    may be used to endorse or promote products derived from this software
49  *    without specific prior written permission.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61  * SUCH DAMAGE.
62  *
63  *	@(#)procfs_subr.c	8.6 (Berkeley) 5/14/95
64  */
65 
66 /*
67  * Copyright (c) 1994 Christopher G. Demetriou.  All rights reserved.
68  * Copyright (c) 1993 Jan-Simon Pendry
69  *
70  * This code is derived from software contributed to Berkeley by
71  * Jan-Simon Pendry.
72  *
73  * Redistribution and use in source and binary forms, with or without
74  * modification, are permitted provided that the following conditions
75  * are met:
76  * 1. Redistributions of source code must retain the above copyright
77  *    notice, this list of conditions and the following disclaimer.
78  * 2. Redistributions in binary form must reproduce the above copyright
79  *    notice, this list of conditions and the following disclaimer in the
80  *    documentation and/or other materials provided with the distribution.
81  * 3. All advertising materials mentioning features or use of this software
82  *    must display the following acknowledgement:
83  *	This product includes software developed by the University of
84  *	California, Berkeley and its contributors.
85  * 4. Neither the name of the University nor the names of its contributors
86  *    may be used to endorse or promote products derived from this software
87  *    without specific prior written permission.
88  *
89  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
90  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
91  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
92  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
93  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
94  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
95  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
96  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
97  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
98  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
99  * SUCH DAMAGE.
100  *
101  *	@(#)procfs_subr.c	8.6 (Berkeley) 5/14/95
102  */
103 
104 #include <sys/cdefs.h>
105 __KERNEL_RCSID(0, "$NetBSD: procfs_subr.c,v 1.101 2012/05/28 13:16:10 christos Exp $");
106 
107 #include <sys/param.h>
108 #include <sys/systm.h>
109 #include <sys/time.h>
110 #include <sys/kernel.h>
111 #include <sys/proc.h>
112 #include <sys/vnode.h>
113 #include <sys/malloc.h>
114 #include <sys/stat.h>
115 #include <sys/file.h>
116 #include <sys/filedesc.h>
117 #include <sys/kauth.h>
118 
119 #include <miscfs/procfs/procfs.h>
120 
121 void procfs_hashins(struct pfsnode *);
122 void procfs_hashrem(struct pfsnode *);
123 struct vnode *procfs_hashget(pid_t, pfstype, int, struct mount *, int);
124 
125 LIST_HEAD(pfs_hashhead, pfsnode) *pfs_hashtbl;
126 u_long	pfs_ihash;	/* size of hash table - 1 */
127 #define PFSPIDHASH(pid)	((pid) & pfs_ihash)
128 
129 kmutex_t pfs_hashlock;
130 kmutex_t pfs_ihash_lock;
131 
132 #define	ISSET(t, f)	((t) & (f))
133 
134 /*
135  * allocate a pfsnode/vnode pair.  the vnode is
136  * referenced, and locked.
137  *
138  * the pid, pfs_type, and mount point uniquely
139  * identify a pfsnode.  the mount point is needed
140  * because someone might mount this filesystem
141  * twice.
142  *
143  * all pfsnodes are maintained on a singly-linked
144  * list.  new nodes are only allocated when they cannot
145  * be found on this list.  entries on the list are
146  * removed when the vfs reclaim entry is called.
147  *
148  * a single lock is kept for the entire list.  this is
149  * needed because the getnewvnode() function can block
150  * waiting for a vnode to become free, in which case there
151  * may be more than one process trying to get the same
152  * vnode.  this lock is only taken if we are going to
153  * call getnewvnode, since the kernel itself is single-threaded.
154  *
155  * if an entry is found on the list, then call vget() to
156  * take a reference.  this is done because there may be
157  * zero references to it and so it needs to removed from
158  * the vnode free list.
159  */
160 int
161 procfs_allocvp(struct mount *mp, struct vnode **vpp, pid_t pid,
162     pfstype pfs_type, int fd, struct proc *p)
163 {
164 	struct pfsnode *pfs;
165 	struct vnode *vp;
166 	int error;
167 
168  retry:
169 	*vpp = procfs_hashget(pid, pfs_type, fd, mp, LK_EXCLUSIVE);
170 	if (*vpp != NULL)
171 		return (0);
172 
173 	error = getnewvnode(VT_PROCFS, mp, procfs_vnodeop_p, NULL, &vp);
174 	if (error) {
175 		*vpp = NULL;
176 		return (error);
177 	}
178 	pfs = malloc(sizeof(struct pfsnode), M_TEMP, M_WAITOK);
179 
180 	mutex_enter(&pfs_hashlock);
181 	if ((*vpp = procfs_hashget(pid, pfs_type, fd, mp, 0)) != NULL) {
182 		mutex_exit(&pfs_hashlock);
183 		ungetnewvnode(vp);
184 		free(pfs, M_TEMP);
185 		goto retry;
186 	}
187 
188 	vp->v_data = pfs;
189 	pfs->pfs_pid = pid;
190 	pfs->pfs_type = pfs_type;
191 	pfs->pfs_vnode = vp;
192 	pfs->pfs_flags = 0;
193 	pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type, fd);
194 	pfs->pfs_fd = fd;
195 
196 	switch (pfs_type) {
197 	case PFSroot:	/* /proc = dr-xr-xr-x */
198 		vp->v_vflag |= VV_ROOT;
199 		/*FALLTHROUGH*/
200 	case PFSproc:	/* /proc/N = dr-xr-xr-x */
201 		pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
202 		vp->v_type = VDIR;
203 		break;
204 
205 	case PFStask:	/* /proc/N/task = dr-xr-xr-x */
206 		if (fd == -1) {
207 			pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|
208 			    S_IROTH|S_IXOTH;
209 			vp->v_type = VDIR;
210 			break;
211 		}
212 		/*FALLTHROUGH*/
213 	case PFScurproc:	/* /proc/curproc = lr-xr-xr-x */
214 	case PFSself:	/* /proc/self    = lr-xr-xr-x */
215 	case PFScwd:	/* /proc/N/cwd = lr-xr-xr-x */
216 	case PFSchroot:	/* /proc/N/chroot = lr-xr-xr-x */
217 	case PFSexe:	/* /proc/N/exe = lr-xr-xr-x */
218 		pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
219 		vp->v_type = VLNK;
220 		break;
221 
222 	case PFSfd:
223 		if (fd == -1) {	/* /proc/N/fd = dr-x------ */
224 			pfs->pfs_mode = S_IRUSR|S_IXUSR;
225 			vp->v_type = VDIR;
226 		} else {	/* /proc/N/fd/M = [ps-]rw------- */
227 			file_t *fp;
228 			vnode_t *vxp;
229 
230 			if ((fp = fd_getfile2(p, pfs->pfs_fd)) == NULL) {
231 				error = EBADF;
232 				goto bad;
233 			}
234 
235 			pfs->pfs_mode = S_IRUSR|S_IWUSR;
236 			switch (fp->f_type) {
237 			case DTYPE_VNODE:
238 				vxp = fp->f_data;
239 
240 				/*
241 				 * We make symlinks for directories
242 				 * to avoid cycles.
243 				 */
244 				if (vxp->v_type == VDIR)
245 					goto symlink;
246 				vp->v_type = vxp->v_type;
247 				break;
248 			case DTYPE_PIPE:
249 				vp->v_type = VFIFO;
250 				break;
251 			case DTYPE_SOCKET:
252 				vp->v_type = VSOCK;
253 				break;
254 			case DTYPE_KQUEUE:
255 			case DTYPE_MISC:
256 			symlink:
257 				pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|
258 				    S_IXGRP|S_IROTH|S_IXOTH;
259 				vp->v_type = VLNK;
260 				break;
261 			default:
262 				error = EOPNOTSUPP;
263 				closef(fp);
264 				goto bad;
265 			}
266 			closef(fp);
267 		}
268 		break;
269 
270 	case PFSfile:	/* /proc/N/file = -rw------- */
271 	case PFSmem:	/* /proc/N/mem = -rw------- */
272 	case PFSregs:	/* /proc/N/regs = -rw------- */
273 	case PFSfpregs:	/* /proc/N/fpregs = -rw------- */
274 		pfs->pfs_mode = S_IRUSR|S_IWUSR;
275 		vp->v_type = VREG;
276 		break;
277 
278 	case PFSctl:	/* /proc/N/ctl = --w------ */
279 	case PFSnote:	/* /proc/N/note = --w------ */
280 	case PFSnotepg:	/* /proc/N/notepg = --w------ */
281 		pfs->pfs_mode = S_IWUSR;
282 		vp->v_type = VREG;
283 		break;
284 
285 	case PFSmap:	/* /proc/N/map = -r--r--r-- */
286 	case PFSmaps:	/* /proc/N/maps = -r--r--r-- */
287 	case PFSstatus:	/* /proc/N/status = -r--r--r-- */
288 	case PFSstat:	/* /proc/N/stat = -r--r--r-- */
289 	case PFScmdline:	/* /proc/N/cmdline = -r--r--r-- */
290 	case PFSemul:	/* /proc/N/emul = -r--r--r-- */
291 	case PFSmeminfo:	/* /proc/meminfo = -r--r--r-- */
292 	case PFScpustat:	/* /proc/stat = -r--r--r-- */
293 	case PFSdevices:	/* /proc/devices = -r--r--r-- */
294 	case PFScpuinfo:	/* /proc/cpuinfo = -r--r--r-- */
295 	case PFSuptime:	/* /proc/uptime = -r--r--r-- */
296 	case PFSmounts:	/* /proc/mounts = -r--r--r-- */
297 	case PFSloadavg:	/* /proc/loadavg = -r--r--r-- */
298 	case PFSstatm:	/* /proc/N/statm = -r--r--r-- */
299 	case PFSversion:	/* /proc/version = -r--r--r-- */
300 		pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH;
301 		vp->v_type = VREG;
302 		break;
303 
304 #ifdef __HAVE_PROCFS_MACHDEP
305 	PROCFS_MACHDEP_NODETYPE_CASES
306 		procfs_machdep_allocvp(vp);
307 		break;
308 #endif
309 
310 	default:
311 		panic("procfs_allocvp");
312 	}
313 
314 	procfs_hashins(pfs);
315 	uvm_vnp_setsize(vp, 0);
316 	mutex_exit(&pfs_hashlock);
317 
318 	*vpp = vp;
319 	return (0);
320 
321  bad:
322 	mutex_exit(&pfs_hashlock);
323 	free(pfs, M_TEMP);
324 	vp->v_data = NULL;
325 	ungetnewvnode(vp);
326 	return (error);
327 }
328 
329 int
330 procfs_freevp(struct vnode *vp)
331 {
332 	struct pfsnode *pfs = VTOPFS(vp);
333 
334 	procfs_hashrem(pfs);
335 
336 	free(vp->v_data, M_TEMP);
337 	vp->v_data = NULL;
338 	return (0);
339 }
340 
341 int
342 procfs_rw(void *v)
343 {
344 	struct vop_read_args *ap = v;
345 	struct vnode *vp = ap->a_vp;
346 	struct uio *uio = ap->a_uio;
347 	struct lwp *curl;
348 	struct lwp *l;
349 	struct pfsnode *pfs = VTOPFS(vp);
350 	struct proc *p;
351 	int error;
352 
353 	if (uio->uio_offset < 0)
354 		return EINVAL;
355 
356 	if ((error = procfs_proc_lock(pfs->pfs_pid, &p, ESRCH)) != 0)
357 		return error;
358 
359 	curl = curlwp;
360 
361 	/*
362 	 * Do not allow init to be modified while in secure mode; it
363 	 * could be duped into changing the security level.
364 	 */
365 #define	M2K(m)	((m) == UIO_READ ? KAUTH_REQ_PROCESS_PROCFS_READ : \
366 		 KAUTH_REQ_PROCESS_PROCFS_WRITE)
367 	mutex_enter(p->p_lock);
368 	error = kauth_authorize_process(curl->l_cred, KAUTH_PROCESS_PROCFS,
369 	    p, pfs, KAUTH_ARG(M2K(uio->uio_rw)), NULL);
370 	mutex_exit(p->p_lock);
371 	if (error) {
372 		procfs_proc_unlock(p);
373 		return (error);
374 	}
375 #undef	M2K
376 
377 	mutex_enter(p->p_lock);
378 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
379 		if (l->l_stat != LSZOMB)
380 			break;
381 	}
382 	/* Process is exiting if no-LWPS or all LWPs are LSZOMB */
383 	if (l == NULL) {
384 		mutex_exit(p->p_lock);
385 		procfs_proc_unlock(p);
386 		return ESRCH;
387 	}
388 
389 	lwp_addref(l);
390 	mutex_exit(p->p_lock);
391 
392 	switch (pfs->pfs_type) {
393 	case PFSnote:
394 	case PFSnotepg:
395 		error = procfs_donote(curl, p, pfs, uio);
396 		break;
397 
398 	case PFSregs:
399 		error = procfs_doregs(curl, l, pfs, uio);
400 		break;
401 
402 	case PFSfpregs:
403 		error = procfs_dofpregs(curl, l, pfs, uio);
404 		break;
405 
406 	case PFSctl:
407 		error = procfs_doctl(curl, l, pfs, uio);
408 		break;
409 
410 	case PFSstatus:
411 		error = procfs_dostatus(curl, l, pfs, uio);
412 		break;
413 
414 	case PFSstat:
415 		error = procfs_do_pid_stat(curl, l, pfs, uio);
416 		break;
417 
418 	case PFSmap:
419 		error = procfs_domap(curl, p, pfs, uio, 0);
420 		break;
421 
422 	case PFSmaps:
423 		error = procfs_domap(curl, p, pfs, uio, 1);
424 		break;
425 
426 	case PFSmem:
427 		error = procfs_domem(curl, l, pfs, uio);
428 		break;
429 
430 	case PFScmdline:
431 		error = procfs_docmdline(curl, p, pfs, uio);
432 		break;
433 
434 	case PFSmeminfo:
435 		error = procfs_domeminfo(curl, p, pfs, uio);
436 		break;
437 
438 	case PFSdevices:
439 		error = procfs_dodevices(curl, p, pfs, uio);
440 		break;
441 
442 	case PFScpuinfo:
443 		error = procfs_docpuinfo(curl, p, pfs, uio);
444 		break;
445 
446 	case PFScpustat:
447 		error = procfs_docpustat(curl, p, pfs, uio);
448 		break;
449 
450 	case PFSloadavg:
451 		error = procfs_doloadavg(curl, p, pfs, uio);
452 		break;
453 
454 	case PFSstatm:
455 		error = procfs_do_pid_statm(curl, l, pfs, uio);
456 		break;
457 
458 	case PFSfd:
459 		error = procfs_dofd(curl, p, pfs, uio);
460 		break;
461 
462 	case PFSuptime:
463 		error = procfs_douptime(curl, p, pfs, uio);
464 		break;
465 
466 	case PFSmounts:
467 		error = procfs_domounts(curl, p, pfs, uio);
468 		break;
469 
470 	case PFSemul:
471 		error = procfs_doemul(curl, p, pfs, uio);
472 		break;
473 
474 	case PFSversion:
475 		error = procfs_doversion(curl, p, pfs, uio);
476 		break;
477 
478 #ifdef __HAVE_PROCFS_MACHDEP
479 	PROCFS_MACHDEP_NODETYPE_CASES
480 		error = procfs_machdep_rw(curl, l, pfs, uio);
481 		break;
482 #endif
483 
484 	default:
485 		error = EOPNOTSUPP;
486 		break;
487 	}
488 
489 	/*
490 	 * Release the references that we acquired earlier.
491 	 */
492 	lwp_delref(l);
493 	procfs_proc_unlock(p);
494 
495 	return (error);
496 }
497 
498 /*
499  * Get a string from userland into (bf).  Strip a trailing
500  * nl character (to allow easy access from the shell).
501  * The buffer should be *buflenp + 1 chars long.  vfs_getuserstr
502  * will automatically add a nul char at the end.
503  *
504  * Returns 0 on success or the following errors
505  *
506  * EINVAL:    file offset is non-zero.
507  * EMSGSIZE:  message is longer than kernel buffer
508  * EFAULT:    user i/o buffer is not addressable
509  */
510 int
511 vfs_getuserstr(struct uio *uio, char *bf, int *buflenp)
512 {
513 	int xlen;
514 	int error;
515 
516 	if (uio->uio_offset != 0)
517 		return (EINVAL);
518 
519 	xlen = *buflenp;
520 
521 	/* must be able to read the whole string in one go */
522 	if (xlen < uio->uio_resid)
523 		return (EMSGSIZE);
524 	xlen = uio->uio_resid;
525 
526 	if ((error = uiomove(bf, xlen, uio)) != 0)
527 		return (error);
528 
529 	/* allow multiple writes without seeks */
530 	uio->uio_offset = 0;
531 
532 	/* cleanup string and remove trailing newline */
533 	bf[xlen] = '\0';
534 	xlen = strlen(bf);
535 	if (xlen > 0 && bf[xlen-1] == '\n')
536 		bf[--xlen] = '\0';
537 	*buflenp = xlen;
538 
539 	return (0);
540 }
541 
542 const vfs_namemap_t *
543 vfs_findname(const vfs_namemap_t *nm, const char *bf, int buflen)
544 {
545 
546 	for (; nm->nm_name; nm++)
547 		if (memcmp(bf, nm->nm_name, buflen+1) == 0)
548 			return (nm);
549 
550 	return (0);
551 }
552 
553 /*
554  * Initialize pfsnode hash table.
555  */
556 void
557 procfs_hashinit(void)
558 {
559 	mutex_init(&pfs_hashlock, MUTEX_DEFAULT, IPL_NONE);
560 	mutex_init(&pfs_ihash_lock, MUTEX_DEFAULT, IPL_NONE);
561 	pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, true, &pfs_ihash);
562 }
563 
564 void
565 procfs_hashreinit(void)
566 {
567 	struct pfsnode *pp;
568 	struct pfs_hashhead *oldhash, *hash;
569 	u_long i, oldmask, mask, val;
570 
571 	hash = hashinit(desiredvnodes / 4, HASH_LIST, true, &mask);
572 
573 	mutex_enter(&pfs_ihash_lock);
574 	oldhash = pfs_hashtbl;
575 	oldmask = pfs_ihash;
576 	pfs_hashtbl = hash;
577 	pfs_ihash = mask;
578 	for (i = 0; i <= oldmask; i++) {
579 		while ((pp = LIST_FIRST(&oldhash[i])) != NULL) {
580 			LIST_REMOVE(pp, pfs_hash);
581 			val = PFSPIDHASH(pp->pfs_pid);
582 			LIST_INSERT_HEAD(&hash[val], pp, pfs_hash);
583 		}
584 	}
585 	mutex_exit(&pfs_ihash_lock);
586 	hashdone(oldhash, HASH_LIST, oldmask);
587 }
588 
589 /*
590  * Free pfsnode hash table.
591  */
592 void
593 procfs_hashdone(void)
594 {
595 	hashdone(pfs_hashtbl, HASH_LIST, pfs_ihash);
596 	mutex_destroy(&pfs_hashlock);
597 	mutex_destroy(&pfs_ihash_lock);
598 }
599 
600 struct vnode *
601 procfs_hashget(pid_t pid, pfstype type, int fd, struct mount *mp, int flags)
602 {
603 	struct pfs_hashhead *ppp;
604 	struct pfsnode *pp;
605 	struct vnode *vp;
606 
607 loop:
608 	mutex_enter(&pfs_ihash_lock);
609 	ppp = &pfs_hashtbl[PFSPIDHASH(pid)];
610 	LIST_FOREACH(pp, ppp, pfs_hash) {
611 		vp = PFSTOV(pp);
612 		if (pid == pp->pfs_pid && pp->pfs_type == type &&
613 		    pp->pfs_fd == fd && vp->v_mount == mp) {
614 		    	if (flags == 0) {
615 				mutex_exit(&pfs_ihash_lock);
616 			} else {
617 				mutex_enter(vp->v_interlock);
618 				mutex_exit(&pfs_ihash_lock);
619 				if (vget(vp, flags))
620 					goto loop;
621 			}
622 			return (vp);
623 		}
624 	}
625 	mutex_exit(&pfs_ihash_lock);
626 	return (NULL);
627 }
628 
629 /*
630  * Insert the pfsnode into the hash table and lock it.
631  */
632 void
633 procfs_hashins(struct pfsnode *pp)
634 {
635 	struct pfs_hashhead *ppp;
636 
637 	/* lock the pfsnode, then put it on the appropriate hash list */
638 	VOP_LOCK(PFSTOV(pp), LK_EXCLUSIVE);
639 
640 	mutex_enter(&pfs_ihash_lock);
641 	ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)];
642 	LIST_INSERT_HEAD(ppp, pp, pfs_hash);
643 	mutex_exit(&pfs_ihash_lock);
644 }
645 
646 /*
647  * Remove the pfsnode from the hash table.
648  */
649 void
650 procfs_hashrem(struct pfsnode *pp)
651 {
652 	mutex_enter(&pfs_ihash_lock);
653 	LIST_REMOVE(pp, pfs_hash);
654 	mutex_exit(&pfs_ihash_lock);
655 }
656 
657 void
658 procfs_revoke_vnodes(struct proc *p, void *arg)
659 {
660 	struct pfsnode *pfs, *pnext;
661 	struct vnode *vp;
662 	struct mount *mp = (struct mount *)arg;
663 	struct pfs_hashhead *ppp;
664 
665 	if (!(p->p_flag & PK_SUGID))
666 		return;
667 
668 	mutex_enter(&pfs_ihash_lock);
669 	ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)];
670 	for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) {
671 		vp = PFSTOV(pfs);
672 		pnext = LIST_NEXT(pfs, pfs_hash);
673 		mutex_enter(vp->v_interlock);
674 		if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid &&
675 		    vp->v_mount == mp) {
676 		    	vp->v_usecount++;
677 		    	mutex_exit(vp->v_interlock);
678 			mutex_exit(&pfs_ihash_lock);
679 			VOP_REVOKE(vp, REVOKEALL);
680 			vrele(vp);
681 			mutex_enter(&pfs_ihash_lock);
682 		} else {
683 			mutex_exit(vp->v_interlock);
684 		}
685 	}
686 	mutex_exit(&pfs_ihash_lock);
687 }
688 
689 int
690 procfs_proc_lock(int pid, struct proc **bunghole, int notfound)
691 {
692 	struct proc *tp;
693 	int error = 0;
694 
695 	mutex_enter(proc_lock);
696 
697 	if (pid == 0)
698 		tp = &proc0;
699 	else if ((tp = proc_find(pid)) == NULL)
700 		error = notfound;
701 	if (tp != NULL && !rw_tryenter(&tp->p_reflock, RW_READER))
702 		error = EBUSY;
703 
704 	mutex_exit(proc_lock);
705 
706 	*bunghole = tp;
707 	return error;
708 }
709 
710 void
711 procfs_proc_unlock(struct proc *p)
712 {
713 
714 	rw_exit(&p->p_reflock);
715 }
716 
717 int
718 procfs_doemul(struct lwp *curl, struct proc *p,
719     struct pfsnode *pfs, struct uio *uio)
720 {
721 	const char *ename = p->p_emul->e_name;
722 	return uiomove_frombuf(__UNCONST(ename), strlen(ename), uio);
723 }
724