xref: /netbsd-src/sys/miscfs/procfs/procfs_subr.c (revision a536ee5124e62c9a0051a252f7833dc8f50f44c9)
1 /*	$NetBSD: procfs_subr.c,v 1.102 2012/11/25 01:03:05 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 1.102 2012/11/25 01:03:05 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 			case DTYPE_SEM:
257 			symlink:
258 				pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|
259 				    S_IXGRP|S_IROTH|S_IXOTH;
260 				vp->v_type = VLNK;
261 				break;
262 			default:
263 				error = EOPNOTSUPP;
264 				closef(fp);
265 				goto bad;
266 			}
267 			closef(fp);
268 		}
269 		break;
270 
271 	case PFSfile:	/* /proc/N/file = -rw------- */
272 	case PFSmem:	/* /proc/N/mem = -rw------- */
273 	case PFSregs:	/* /proc/N/regs = -rw------- */
274 	case PFSfpregs:	/* /proc/N/fpregs = -rw------- */
275 		pfs->pfs_mode = S_IRUSR|S_IWUSR;
276 		vp->v_type = VREG;
277 		break;
278 
279 	case PFSctl:	/* /proc/N/ctl = --w------ */
280 	case PFSnote:	/* /proc/N/note = --w------ */
281 	case PFSnotepg:	/* /proc/N/notepg = --w------ */
282 		pfs->pfs_mode = S_IWUSR;
283 		vp->v_type = VREG;
284 		break;
285 
286 	case PFSmap:	/* /proc/N/map = -r--r--r-- */
287 	case PFSmaps:	/* /proc/N/maps = -r--r--r-- */
288 	case PFSstatus:	/* /proc/N/status = -r--r--r-- */
289 	case PFSstat:	/* /proc/N/stat = -r--r--r-- */
290 	case PFScmdline:	/* /proc/N/cmdline = -r--r--r-- */
291 	case PFSemul:	/* /proc/N/emul = -r--r--r-- */
292 	case PFSmeminfo:	/* /proc/meminfo = -r--r--r-- */
293 	case PFScpustat:	/* /proc/stat = -r--r--r-- */
294 	case PFSdevices:	/* /proc/devices = -r--r--r-- */
295 	case PFScpuinfo:	/* /proc/cpuinfo = -r--r--r-- */
296 	case PFSuptime:	/* /proc/uptime = -r--r--r-- */
297 	case PFSmounts:	/* /proc/mounts = -r--r--r-- */
298 	case PFSloadavg:	/* /proc/loadavg = -r--r--r-- */
299 	case PFSstatm:	/* /proc/N/statm = -r--r--r-- */
300 	case PFSversion:	/* /proc/version = -r--r--r-- */
301 		pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH;
302 		vp->v_type = VREG;
303 		break;
304 
305 #ifdef __HAVE_PROCFS_MACHDEP
306 	PROCFS_MACHDEP_NODETYPE_CASES
307 		procfs_machdep_allocvp(vp);
308 		break;
309 #endif
310 
311 	default:
312 		panic("procfs_allocvp");
313 	}
314 
315 	procfs_hashins(pfs);
316 	uvm_vnp_setsize(vp, 0);
317 	mutex_exit(&pfs_hashlock);
318 
319 	*vpp = vp;
320 	return (0);
321 
322  bad:
323 	mutex_exit(&pfs_hashlock);
324 	free(pfs, M_TEMP);
325 	vp->v_data = NULL;
326 	ungetnewvnode(vp);
327 	return (error);
328 }
329 
330 int
331 procfs_freevp(struct vnode *vp)
332 {
333 	struct pfsnode *pfs = VTOPFS(vp);
334 
335 	procfs_hashrem(pfs);
336 
337 	free(vp->v_data, M_TEMP);
338 	vp->v_data = NULL;
339 	return (0);
340 }
341 
342 int
343 procfs_rw(void *v)
344 {
345 	struct vop_read_args *ap = v;
346 	struct vnode *vp = ap->a_vp;
347 	struct uio *uio = ap->a_uio;
348 	struct lwp *curl;
349 	struct lwp *l;
350 	struct pfsnode *pfs = VTOPFS(vp);
351 	struct proc *p;
352 	int error;
353 
354 	if (uio->uio_offset < 0)
355 		return EINVAL;
356 
357 	if ((error = procfs_proc_lock(pfs->pfs_pid, &p, ESRCH)) != 0)
358 		return error;
359 
360 	curl = curlwp;
361 
362 	/*
363 	 * Do not allow init to be modified while in secure mode; it
364 	 * could be duped into changing the security level.
365 	 */
366 #define	M2K(m)	((m) == UIO_READ ? KAUTH_REQ_PROCESS_PROCFS_READ : \
367 		 KAUTH_REQ_PROCESS_PROCFS_WRITE)
368 	mutex_enter(p->p_lock);
369 	error = kauth_authorize_process(curl->l_cred, KAUTH_PROCESS_PROCFS,
370 	    p, pfs, KAUTH_ARG(M2K(uio->uio_rw)), NULL);
371 	mutex_exit(p->p_lock);
372 	if (error) {
373 		procfs_proc_unlock(p);
374 		return (error);
375 	}
376 #undef	M2K
377 
378 	mutex_enter(p->p_lock);
379 	LIST_FOREACH(l, &p->p_lwps, l_sibling) {
380 		if (l->l_stat != LSZOMB)
381 			break;
382 	}
383 	/* Process is exiting if no-LWPS or all LWPs are LSZOMB */
384 	if (l == NULL) {
385 		mutex_exit(p->p_lock);
386 		procfs_proc_unlock(p);
387 		return ESRCH;
388 	}
389 
390 	lwp_addref(l);
391 	mutex_exit(p->p_lock);
392 
393 	switch (pfs->pfs_type) {
394 	case PFSnote:
395 	case PFSnotepg:
396 		error = procfs_donote(curl, p, pfs, uio);
397 		break;
398 
399 	case PFSregs:
400 		error = procfs_doregs(curl, l, pfs, uio);
401 		break;
402 
403 	case PFSfpregs:
404 		error = procfs_dofpregs(curl, l, pfs, uio);
405 		break;
406 
407 	case PFSctl:
408 		error = procfs_doctl(curl, l, pfs, uio);
409 		break;
410 
411 	case PFSstatus:
412 		error = procfs_dostatus(curl, l, pfs, uio);
413 		break;
414 
415 	case PFSstat:
416 		error = procfs_do_pid_stat(curl, l, pfs, uio);
417 		break;
418 
419 	case PFSmap:
420 		error = procfs_domap(curl, p, pfs, uio, 0);
421 		break;
422 
423 	case PFSmaps:
424 		error = procfs_domap(curl, p, pfs, uio, 1);
425 		break;
426 
427 	case PFSmem:
428 		error = procfs_domem(curl, l, pfs, uio);
429 		break;
430 
431 	case PFScmdline:
432 		error = procfs_docmdline(curl, p, pfs, uio);
433 		break;
434 
435 	case PFSmeminfo:
436 		error = procfs_domeminfo(curl, p, pfs, uio);
437 		break;
438 
439 	case PFSdevices:
440 		error = procfs_dodevices(curl, p, pfs, uio);
441 		break;
442 
443 	case PFScpuinfo:
444 		error = procfs_docpuinfo(curl, p, pfs, uio);
445 		break;
446 
447 	case PFScpustat:
448 		error = procfs_docpustat(curl, p, pfs, uio);
449 		break;
450 
451 	case PFSloadavg:
452 		error = procfs_doloadavg(curl, p, pfs, uio);
453 		break;
454 
455 	case PFSstatm:
456 		error = procfs_do_pid_statm(curl, l, pfs, uio);
457 		break;
458 
459 	case PFSfd:
460 		error = procfs_dofd(curl, p, pfs, uio);
461 		break;
462 
463 	case PFSuptime:
464 		error = procfs_douptime(curl, p, pfs, uio);
465 		break;
466 
467 	case PFSmounts:
468 		error = procfs_domounts(curl, p, pfs, uio);
469 		break;
470 
471 	case PFSemul:
472 		error = procfs_doemul(curl, p, pfs, uio);
473 		break;
474 
475 	case PFSversion:
476 		error = procfs_doversion(curl, p, pfs, uio);
477 		break;
478 
479 #ifdef __HAVE_PROCFS_MACHDEP
480 	PROCFS_MACHDEP_NODETYPE_CASES
481 		error = procfs_machdep_rw(curl, l, pfs, uio);
482 		break;
483 #endif
484 
485 	default:
486 		error = EOPNOTSUPP;
487 		break;
488 	}
489 
490 	/*
491 	 * Release the references that we acquired earlier.
492 	 */
493 	lwp_delref(l);
494 	procfs_proc_unlock(p);
495 
496 	return (error);
497 }
498 
499 /*
500  * Get a string from userland into (bf).  Strip a trailing
501  * nl character (to allow easy access from the shell).
502  * The buffer should be *buflenp + 1 chars long.  vfs_getuserstr
503  * will automatically add a nul char at the end.
504  *
505  * Returns 0 on success or the following errors
506  *
507  * EINVAL:    file offset is non-zero.
508  * EMSGSIZE:  message is longer than kernel buffer
509  * EFAULT:    user i/o buffer is not addressable
510  */
511 int
512 vfs_getuserstr(struct uio *uio, char *bf, int *buflenp)
513 {
514 	int xlen;
515 	int error;
516 
517 	if (uio->uio_offset != 0)
518 		return (EINVAL);
519 
520 	xlen = *buflenp;
521 
522 	/* must be able to read the whole string in one go */
523 	if (xlen < uio->uio_resid)
524 		return (EMSGSIZE);
525 	xlen = uio->uio_resid;
526 
527 	if ((error = uiomove(bf, xlen, uio)) != 0)
528 		return (error);
529 
530 	/* allow multiple writes without seeks */
531 	uio->uio_offset = 0;
532 
533 	/* cleanup string and remove trailing newline */
534 	bf[xlen] = '\0';
535 	xlen = strlen(bf);
536 	if (xlen > 0 && bf[xlen-1] == '\n')
537 		bf[--xlen] = '\0';
538 	*buflenp = xlen;
539 
540 	return (0);
541 }
542 
543 const vfs_namemap_t *
544 vfs_findname(const vfs_namemap_t *nm, const char *bf, int buflen)
545 {
546 
547 	for (; nm->nm_name; nm++)
548 		if (memcmp(bf, nm->nm_name, buflen+1) == 0)
549 			return (nm);
550 
551 	return (0);
552 }
553 
554 /*
555  * Initialize pfsnode hash table.
556  */
557 void
558 procfs_hashinit(void)
559 {
560 	mutex_init(&pfs_hashlock, MUTEX_DEFAULT, IPL_NONE);
561 	mutex_init(&pfs_ihash_lock, MUTEX_DEFAULT, IPL_NONE);
562 	pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, true, &pfs_ihash);
563 }
564 
565 void
566 procfs_hashreinit(void)
567 {
568 	struct pfsnode *pp;
569 	struct pfs_hashhead *oldhash, *hash;
570 	u_long i, oldmask, mask, val;
571 
572 	hash = hashinit(desiredvnodes / 4, HASH_LIST, true, &mask);
573 
574 	mutex_enter(&pfs_ihash_lock);
575 	oldhash = pfs_hashtbl;
576 	oldmask = pfs_ihash;
577 	pfs_hashtbl = hash;
578 	pfs_ihash = mask;
579 	for (i = 0; i <= oldmask; i++) {
580 		while ((pp = LIST_FIRST(&oldhash[i])) != NULL) {
581 			LIST_REMOVE(pp, pfs_hash);
582 			val = PFSPIDHASH(pp->pfs_pid);
583 			LIST_INSERT_HEAD(&hash[val], pp, pfs_hash);
584 		}
585 	}
586 	mutex_exit(&pfs_ihash_lock);
587 	hashdone(oldhash, HASH_LIST, oldmask);
588 }
589 
590 /*
591  * Free pfsnode hash table.
592  */
593 void
594 procfs_hashdone(void)
595 {
596 	hashdone(pfs_hashtbl, HASH_LIST, pfs_ihash);
597 	mutex_destroy(&pfs_hashlock);
598 	mutex_destroy(&pfs_ihash_lock);
599 }
600 
601 struct vnode *
602 procfs_hashget(pid_t pid, pfstype type, int fd, struct mount *mp, int flags)
603 {
604 	struct pfs_hashhead *ppp;
605 	struct pfsnode *pp;
606 	struct vnode *vp;
607 
608 loop:
609 	mutex_enter(&pfs_ihash_lock);
610 	ppp = &pfs_hashtbl[PFSPIDHASH(pid)];
611 	LIST_FOREACH(pp, ppp, pfs_hash) {
612 		vp = PFSTOV(pp);
613 		if (pid == pp->pfs_pid && pp->pfs_type == type &&
614 		    pp->pfs_fd == fd && vp->v_mount == mp) {
615 		    	if (flags == 0) {
616 				mutex_exit(&pfs_ihash_lock);
617 			} else {
618 				mutex_enter(vp->v_interlock);
619 				mutex_exit(&pfs_ihash_lock);
620 				if (vget(vp, flags))
621 					goto loop;
622 			}
623 			return (vp);
624 		}
625 	}
626 	mutex_exit(&pfs_ihash_lock);
627 	return (NULL);
628 }
629 
630 /*
631  * Insert the pfsnode into the hash table and lock it.
632  */
633 void
634 procfs_hashins(struct pfsnode *pp)
635 {
636 	struct pfs_hashhead *ppp;
637 
638 	/* lock the pfsnode, then put it on the appropriate hash list */
639 	VOP_LOCK(PFSTOV(pp), LK_EXCLUSIVE);
640 
641 	mutex_enter(&pfs_ihash_lock);
642 	ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)];
643 	LIST_INSERT_HEAD(ppp, pp, pfs_hash);
644 	mutex_exit(&pfs_ihash_lock);
645 }
646 
647 /*
648  * Remove the pfsnode from the hash table.
649  */
650 void
651 procfs_hashrem(struct pfsnode *pp)
652 {
653 	mutex_enter(&pfs_ihash_lock);
654 	LIST_REMOVE(pp, pfs_hash);
655 	mutex_exit(&pfs_ihash_lock);
656 }
657 
658 void
659 procfs_revoke_vnodes(struct proc *p, void *arg)
660 {
661 	struct pfsnode *pfs, *pnext;
662 	struct vnode *vp;
663 	struct mount *mp = (struct mount *)arg;
664 	struct pfs_hashhead *ppp;
665 
666 	if (!(p->p_flag & PK_SUGID))
667 		return;
668 
669 	mutex_enter(&pfs_ihash_lock);
670 	ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)];
671 	for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) {
672 		vp = PFSTOV(pfs);
673 		pnext = LIST_NEXT(pfs, pfs_hash);
674 		mutex_enter(vp->v_interlock);
675 		if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid &&
676 		    vp->v_mount == mp) {
677 		    	vp->v_usecount++;
678 		    	mutex_exit(vp->v_interlock);
679 			mutex_exit(&pfs_ihash_lock);
680 			VOP_REVOKE(vp, REVOKEALL);
681 			vrele(vp);
682 			mutex_enter(&pfs_ihash_lock);
683 		} else {
684 			mutex_exit(vp->v_interlock);
685 		}
686 	}
687 	mutex_exit(&pfs_ihash_lock);
688 }
689 
690 int
691 procfs_proc_lock(int pid, struct proc **bunghole, int notfound)
692 {
693 	struct proc *tp;
694 	int error = 0;
695 
696 	mutex_enter(proc_lock);
697 
698 	if (pid == 0)
699 		tp = &proc0;
700 	else if ((tp = proc_find(pid)) == NULL)
701 		error = notfound;
702 	if (tp != NULL && !rw_tryenter(&tp->p_reflock, RW_READER))
703 		error = EBUSY;
704 
705 	mutex_exit(proc_lock);
706 
707 	*bunghole = tp;
708 	return error;
709 }
710 
711 void
712 procfs_proc_unlock(struct proc *p)
713 {
714 
715 	rw_exit(&p->p_reflock);
716 }
717 
718 int
719 procfs_doemul(struct lwp *curl, struct proc *p,
720     struct pfsnode *pfs, struct uio *uio)
721 {
722 	const char *ename = p->p_emul->e_name;
723 	return uiomove_frombuf(__UNCONST(ename), strlen(ename), uio);
724 }
725