1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23 /*
24 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
25 * Use is subject to license terms.
26 */
27
28 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
29 /* All Rights Reserved */
30
31
32 #include <sys/param.h>
33 #include <sys/inttypes.h>
34 #include <sys/types.h>
35 #include <sys/sysmacros.h>
36 #include <sys/systm.h>
37 #include <sys/user.h>
38 #include <sys/errno.h>
39 #include <sys/vfs.h>
40 #include <sys/vnode.h>
41 #include <sys/file.h>
42 #include <sys/proc.h>
43 #include <sys/session.h>
44 #include <sys/var.h>
45 #include <sys/utsname.h>
46 #include <sys/utssys.h>
47 #include <sys/ustat.h>
48 #include <sys/statvfs.h>
49 #include <sys/kmem.h>
50 #include <sys/debug.h>
51 #include <sys/pathname.h>
52 #include <sys/modctl.h>
53 #include <sys/fs/snode.h>
54 #include <sys/sunldi_impl.h>
55 #include <sys/ddi.h>
56 #include <sys/sunddi.h>
57 #include <sys/cmn_err.h>
58 #include <sys/ddipropdefs.h>
59 #include <sys/ddi_impldefs.h>
60 #include <sys/modctl.h>
61 #include <sys/flock.h>
62 #include <sys/share.h>
63 #include <vm/as.h>
64 #include <vm/seg.h>
65 #include <vm/seg_vn.h>
66 #include <util/qsort.h>
67 #include <sys/zone.h>
68
69 /*
70 * utssys()
71 */
72 static int uts_fusers(char *, int, intptr_t);
73 static int _statvfs64_by_dev(dev_t, struct statvfs64 *);
74
75 #if defined(_ILP32) || defined(_SYSCALL32_IMPL)
76
77 static int utssys_uname32(caddr_t, rval_t *);
78 static int utssys_ustat32(dev_t, struct ustat32 *);
79
80 int64_t
utssys32(void * buf,int arg,int type,void * outbp)81 utssys32(void *buf, int arg, int type, void *outbp)
82 {
83 int error;
84 rval_t rv;
85
86 rv.r_vals = 0;
87
88 switch (type) {
89 case UTS_UNAME:
90 /*
91 * This is an obsolete way to get the utsname structure
92 * (it only gives you the first 8 characters of each field!)
93 * uname(2) is the preferred and better interface.
94 */
95 error = utssys_uname32(buf, &rv);
96 break;
97 case UTS_USTAT:
98 error = utssys_ustat32(expldev((dev32_t)arg), buf);
99 break;
100 case UTS_FUSERS:
101 error = uts_fusers(buf, arg, (intptr_t)outbp);
102 break;
103 default:
104 error = EINVAL;
105 break;
106 }
107
108 return (error == 0 ? rv.r_vals : (int64_t)set_errno(error));
109 }
110
111 static int
utssys_uname32(caddr_t buf,rval_t * rvp)112 utssys_uname32(caddr_t buf, rval_t *rvp)
113 {
114 if (copyout(utsname.sysname, buf, 8))
115 return (EFAULT);
116 buf += 8;
117 if (subyte(buf, 0) < 0)
118 return (EFAULT);
119 buf++;
120 if (copyout(uts_nodename(), buf, 8))
121 return (EFAULT);
122 buf += 8;
123 if (subyte(buf, 0) < 0)
124 return (EFAULT);
125 buf++;
126 if (copyout(utsname.release, buf, 8))
127 return (EFAULT);
128 buf += 8;
129 if (subyte(buf, 0) < 0)
130 return (EFAULT);
131 buf++;
132 if (copyout(utsname.version, buf, 8))
133 return (EFAULT);
134 buf += 8;
135 if (subyte(buf, 0) < 0)
136 return (EFAULT);
137 buf++;
138 if (copyout(utsname.machine, buf, 8))
139 return (EFAULT);
140 buf += 8;
141 if (subyte(buf, 0) < 0)
142 return (EFAULT);
143 rvp->r_val1 = 1;
144 return (0);
145 }
146
147 static int
utssys_ustat32(dev_t dev,struct ustat32 * cbuf)148 utssys_ustat32(dev_t dev, struct ustat32 *cbuf)
149 {
150 struct ustat32 ust32;
151 struct statvfs64 stvfs;
152 fsblkcnt64_t fsbc64;
153 char *cp, *cp2;
154 int i, error;
155
156 if ((error = _statvfs64_by_dev(dev, &stvfs)) != 0)
157 return (error);
158
159 fsbc64 = stvfs.f_bfree * (stvfs.f_frsize / 512);
160 /*
161 * Check to see if the number of free blocks can be expressed
162 * in 31 bits or whether the number of free files is more than
163 * can be expressed in 32 bits and is not -1 (UINT64_MAX). NFS
164 * Version 2 does not support the number of free files and
165 * hence will return -1. -1, when translated from a 32 bit
166 * quantity to an unsigned 64 bit quantity, turns into UINT64_MAX.
167 */
168 if (fsbc64 > INT32_MAX ||
169 (stvfs.f_ffree > UINT32_MAX && stvfs.f_ffree != UINT64_MAX))
170 return (EOVERFLOW);
171
172 ust32.f_tfree = (daddr32_t)fsbc64;
173 ust32.f_tinode = (ino32_t)stvfs.f_ffree;
174
175 cp = stvfs.f_fstr;
176 cp2 = ust32.f_fname;
177 i = 0;
178 while (i++ < sizeof (ust32.f_fname))
179 if (*cp != '\0')
180 *cp2++ = *cp++;
181 else
182 *cp2++ = '\0';
183 while (*cp != '\0' &&
184 (i++ < sizeof (stvfs.f_fstr) - sizeof (ust32.f_fpack)))
185 cp++;
186 (void) strncpy(ust32.f_fpack, cp + 1, sizeof (ust32.f_fpack));
187
188 if (copyout(&ust32, cbuf, sizeof (ust32)))
189 return (EFAULT);
190 return (0);
191 }
192
193 #endif /* _ILP32 || _SYSCALL32_IMPL */
194
195 #ifdef _LP64
196
197 static int uts_ustat64(dev_t, struct ustat *);
198
199 int64_t
utssys64(void * buf,long arg,int type,void * outbp)200 utssys64(void *buf, long arg, int type, void *outbp)
201 {
202 int error;
203 rval_t rv;
204
205 rv.r_vals = 0;
206
207 switch (type) {
208 case UTS_USTAT:
209 error = uts_ustat64((dev_t)arg, buf);
210 break;
211 case UTS_FUSERS:
212 error = uts_fusers(buf, (int)arg, (intptr_t)outbp);
213 break;
214 default:
215 error = EINVAL;
216 break;
217 }
218
219 return (error == 0 ? rv.r_vals : (int64_t)set_errno(error));
220 }
221
222 static int
uts_ustat64(dev_t dev,struct ustat * cbuf)223 uts_ustat64(dev_t dev, struct ustat *cbuf)
224 {
225 struct ustat ust;
226 struct statvfs64 stvfs;
227 fsblkcnt64_t fsbc64;
228 char *cp, *cp2;
229 int i, error;
230
231 if ((error = _statvfs64_by_dev(dev, &stvfs)) != 0)
232 return (error);
233
234 fsbc64 = stvfs.f_bfree * (stvfs.f_frsize / 512);
235 ust.f_tfree = (daddr_t)fsbc64;
236 ust.f_tinode = (ino_t)stvfs.f_ffree;
237
238 cp = stvfs.f_fstr;
239 cp2 = ust.f_fname;
240 i = 0;
241 while (i++ < sizeof (ust.f_fname))
242 if (*cp != '\0')
243 *cp2++ = *cp++;
244 else
245 *cp2++ = '\0';
246 while (*cp != '\0' &&
247 (i++ < sizeof (stvfs.f_fstr) - sizeof (ust.f_fpack)))
248 cp++;
249 (void) strncpy(ust.f_fpack, cp + 1, sizeof (ust.f_fpack));
250
251 if (copyout(&ust, cbuf, sizeof (ust)))
252 return (EFAULT);
253 return (0);
254 }
255
256 #endif /* _LP64 */
257
258 /*
259 * Utility routine for the ustat implementations.
260 * (If it wasn't for the 'find-by-dev_t' semantic of ustat(2), we could push
261 * this all out into userland, sigh.)
262 */
263 static int
_statvfs64_by_dev(dev_t dev,struct statvfs64 * svp)264 _statvfs64_by_dev(dev_t dev, struct statvfs64 *svp)
265 {
266 vfs_t *vfsp;
267 int error;
268
269 if ((vfsp = vfs_dev2vfsp(dev)) == NULL) {
270 /*
271 * See if it's the root of our zone.
272 */
273 vfsp = curproc->p_zone->zone_rootvp->v_vfsp;
274 if (vfsp->vfs_dev == dev) {
275 VFS_HOLD(vfsp);
276 } else {
277 vfsp = NULL;
278 }
279 }
280 if (vfsp == NULL)
281 return (EINVAL);
282 error = VFS_STATVFS(vfsp, svp);
283 VFS_RELE(vfsp);
284 return (error);
285 }
286
287 /*
288 * Check if this pid has an NBMAND lock or share reservation
289 * on this vp. llp is a snapshoted list of all NBMAND locks
290 * set by this pid. Return 1 if there is an NBMAND lock else
291 * return 0.
292 */
293 static int
proc_has_nbmand_on_vp(vnode_t * vp,pid_t pid,locklist_t * llp)294 proc_has_nbmand_on_vp(vnode_t *vp, pid_t pid, locklist_t *llp)
295 {
296 /*
297 * Any NBMAND lock held by the process on this vp?
298 */
299 while (llp) {
300 if (llp->ll_vp == vp) {
301 return (1);
302 }
303 llp = llp->ll_next;
304 }
305 /*
306 * Any NBMAND share reservation on the vp for this process?
307 */
308 return (proc_has_nbmand_share_on_vp(vp, pid));
309 }
310
311 static fu_data_t *
dofusers(vnode_t * fvp,int flags)312 dofusers(vnode_t *fvp, int flags)
313 {
314 fu_data_t *fu_data;
315 proc_t *prp;
316 vfs_t *cvfsp;
317 pid_t npids, pidx, *pidlist;
318 int v_proc = v.v_proc; /* max # of procs */
319 int pcnt = 0;
320 int contained = (flags & F_CONTAINED);
321 int nbmandonly = (flags & F_NBMANDLIST);
322 int dip_usage = (flags & F_DEVINFO);
323 int fvp_isdev = vn_matchops(fvp, spec_getvnodeops());
324 zone_t *zone = curproc->p_zone;
325 int inglobal = INGLOBALZONE(curproc);
326
327 /* get a pointer to the file system containing this vnode */
328 cvfsp = fvp->v_vfsp;
329 ASSERT(cvfsp);
330
331 /* allocate the data structure to return our results in */
332 fu_data = kmem_alloc(fu_data_size(v_proc), KM_SLEEP);
333 fu_data->fud_user_max = v_proc;
334 fu_data->fud_user_count = 0;
335
336 /* get a snapshot of all the pids we're going to check out */
337 pidlist = kmem_alloc(v_proc * sizeof (pid_t), KM_SLEEP);
338 mutex_enter(&pidlock);
339 for (npids = 0, prp = practive; prp != NULL; prp = prp->p_next) {
340 if (inglobal || prp->p_zone == zone)
341 pidlist[npids++] = prp->p_pid;
342 }
343 mutex_exit(&pidlock);
344
345 /* grab each process and check its file usage */
346 for (pidx = 0; pidx < npids; pidx++) {
347 locklist_t *llp = NULL;
348 uf_info_t *fip;
349 vnode_t *vp;
350 user_t *up;
351 sess_t *sp;
352 uid_t uid;
353 pid_t pid = pidlist[pidx];
354 int i, use_flag = 0;
355
356 /*
357 * grab prp->p_lock using sprlock()
358 * if sprlock() fails the process does not exists anymore
359 */
360 prp = sprlock(pid);
361 if (prp == NULL)
362 continue;
363
364 /* get the processes credential info in case we need it */
365 mutex_enter(&prp->p_crlock);
366 uid = crgetruid(prp->p_cred);
367 mutex_exit(&prp->p_crlock);
368
369 /*
370 * it's safe to drop p_lock here because we
371 * called sprlock() before and it set the SPRLOCK
372 * flag for the process so it won't go away.
373 */
374 mutex_exit(&prp->p_lock);
375
376 /*
377 * now we want to walk a processes open file descriptors
378 * to do this we need to grab the fip->fi_lock. (you
379 * can't hold p_lock when grabbing the fip->fi_lock.)
380 */
381 fip = P_FINFO(prp);
382 mutex_enter(&fip->fi_lock);
383
384 /*
385 * Snapshot nbmand locks for pid
386 */
387 llp = flk_active_nbmand_locks(prp->p_pid);
388 for (i = 0; i < fip->fi_nfiles; i++) {
389 uf_entry_t *ufp;
390 file_t *fp;
391
392 UF_ENTER(ufp, fip, i);
393 if (((fp = ufp->uf_file) == NULL) ||
394 ((vp = fp->f_vnode) == NULL)) {
395 UF_EXIT(ufp);
396 continue;
397 }
398
399 /*
400 * if the target file (fvp) is not a device
401 * and corrosponds to the root of a filesystem
402 * (cvfsp), then check if it contains the file
403 * is use by this process (vp).
404 */
405 if (contained && (vp->v_vfsp == cvfsp))
406 use_flag |= F_OPEN;
407
408 /*
409 * if the target file (fvp) is not a device,
410 * then check if it matches the file in use
411 * by this process (vp).
412 */
413 if (!fvp_isdev && VN_CMP(fvp, vp))
414 use_flag |= F_OPEN;
415
416 /*
417 * if the target file (fvp) is a device,
418 * then check if the current file in use
419 * by this process (vp) maps to the same device
420 * minor node.
421 */
422 if (fvp_isdev &&
423 vn_matchops(vp, spec_getvnodeops()) &&
424 (fvp->v_rdev == vp->v_rdev))
425 use_flag |= F_OPEN;
426
427 /*
428 * if the target file (fvp) is a device,
429 * and we're checking for device instance
430 * usage, then check if the current file in use
431 * by this process (vp) maps to the same device
432 * instance.
433 */
434 if (dip_usage &&
435 vn_matchops(vp, spec_getvnodeops()) &&
436 (VTOCS(fvp)->s_dip == VTOCS(vp)->s_dip))
437 use_flag |= F_OPEN;
438
439 /*
440 * if the current file in use by this process (vp)
441 * doesn't match what we're looking for, move on
442 * to the next file in the process.
443 */
444 if ((use_flag & F_OPEN) == 0) {
445 UF_EXIT(ufp);
446 continue;
447 }
448
449 if (proc_has_nbmand_on_vp(vp, prp->p_pid, llp)) {
450 /* A nbmand found so we're done. */
451 use_flag |= F_NBM;
452 UF_EXIT(ufp);
453 break;
454 }
455 UF_EXIT(ufp);
456 }
457 if (llp)
458 flk_free_locklist(llp);
459
460 mutex_exit(&fip->fi_lock);
461
462 /*
463 * If nbmand usage tracking is desired and no nbmand was
464 * found for this process, then no need to do further
465 * usage tracking for this process.
466 */
467 if (nbmandonly && (!(use_flag & F_NBM))) {
468 /*
469 * grab the process lock again, clear the SPRLOCK
470 * flag, release the process, and continue.
471 */
472 mutex_enter(&prp->p_lock);
473 sprunlock(prp);
474 continue;
475 }
476
477 /*
478 * All other types of usage.
479 * For the next few checks we need to hold p_lock.
480 */
481 mutex_enter(&prp->p_lock);
482 up = PTOU(prp);
483 if (fvp_isdev) {
484 /*
485 * if the target file (fvp) is a device
486 * then check if it matches the processes tty
487 *
488 * we grab s_lock to protect ourselves against
489 * freectty() freeing the vnode out from under us.
490 */
491 sp = prp->p_sessp;
492 mutex_enter(&sp->s_lock);
493 vp = prp->p_sessp->s_vp;
494 if (vp != NULL) {
495 if (fvp->v_rdev == vp->v_rdev)
496 use_flag |= F_TTY;
497
498 if (dip_usage &&
499 (VTOCS(fvp)->s_dip == VTOCS(vp)->s_dip))
500 use_flag |= F_TTY;
501 }
502 mutex_exit(&sp->s_lock);
503 } else {
504 /* check the processes current working directory */
505 if (up->u_cdir &&
506 (VN_CMP(fvp, up->u_cdir) ||
507 (contained && (up->u_cdir->v_vfsp == cvfsp))))
508 use_flag |= F_CDIR;
509
510 /* check the processes root directory */
511 if (up->u_rdir &&
512 (VN_CMP(fvp, up->u_rdir) ||
513 (contained && (up->u_rdir->v_vfsp == cvfsp))))
514 use_flag |= F_RDIR;
515
516 /* check the program text vnode */
517 if (prp->p_exec &&
518 (VN_CMP(fvp, prp->p_exec) ||
519 (contained && (prp->p_exec->v_vfsp == cvfsp))))
520 use_flag |= F_TEXT;
521 }
522
523 /* Now we can drop p_lock again */
524 mutex_exit(&prp->p_lock);
525
526 /*
527 * now we want to walk a processes memory mappings.
528 * to do this we need to grab the prp->p_as lock. (you
529 * can't hold p_lock when grabbing the prp->p_as lock.)
530 */
531 if (prp->p_as != &kas) {
532 struct seg *seg;
533 struct as *as = prp->p_as;
534
535 AS_LOCK_ENTER(as, RW_READER);
536 for (seg = AS_SEGFIRST(as); seg;
537 seg = AS_SEGNEXT(as, seg)) {
538 /*
539 * if we can't get a backing vnode for this
540 * segment then skip it
541 */
542 vp = NULL;
543 if ((SEGOP_GETVP(seg, seg->s_base, &vp)) ||
544 (vp == NULL))
545 continue;
546
547 /*
548 * if the target file (fvp) is not a device
549 * and corrosponds to the root of a filesystem
550 * (cvfsp), then check if it contains the
551 * vnode backing this segment (vp).
552 */
553 if (contained && (vp->v_vfsp == cvfsp)) {
554 use_flag |= F_MAP;
555 break;
556 }
557
558 /*
559 * if the target file (fvp) is not a device,
560 * check if it matches the the vnode backing
561 * this segment (vp).
562 */
563 if (!fvp_isdev && VN_CMP(fvp, vp)) {
564 use_flag |= F_MAP;
565 break;
566 }
567
568 /*
569 * if the target file (fvp) isn't a device,
570 * or the the vnode backing this segment (vp)
571 * isn't a device then continue.
572 */
573 if (!fvp_isdev ||
574 !vn_matchops(vp, spec_getvnodeops()))
575 continue;
576
577 /*
578 * check if the vnode backing this segment
579 * (vp) maps to the same device minor node
580 * as the target device (fvp)
581 */
582 if (fvp->v_rdev == vp->v_rdev) {
583 use_flag |= F_MAP;
584 break;
585 }
586
587 /*
588 * if we're checking for device instance
589 * usage, then check if the vnode backing
590 * this segment (vp) maps to the same device
591 * instance as the target device (fvp).
592 */
593 if (dip_usage &&
594 (VTOCS(fvp)->s_dip == VTOCS(vp)->s_dip)) {
595 use_flag |= F_MAP;
596 break;
597 }
598 }
599 AS_LOCK_EXIT(as);
600 }
601
602 if (use_flag) {
603 ASSERT(pcnt < fu_data->fud_user_max);
604 fu_data->fud_user[pcnt].fu_flags = use_flag;
605 fu_data->fud_user[pcnt].fu_pid = pid;
606 fu_data->fud_user[pcnt].fu_uid = uid;
607 pcnt++;
608 }
609
610 /*
611 * grab the process lock again, clear the SPRLOCK
612 * flag, release the process, and continue.
613 */
614 mutex_enter(&prp->p_lock);
615 sprunlock(prp);
616 }
617
618 kmem_free(pidlist, v_proc * sizeof (pid_t));
619
620 fu_data->fud_user_count = pcnt;
621 return (fu_data);
622 }
623
624 typedef struct dofkusers_arg {
625 vnode_t *fvp;
626 int flags;
627 int *error;
628 fu_data_t *fu_data;
629 } dofkusers_arg_t;
630
631 static int
dofkusers_walker(const ldi_usage_t * ldi_usage,void * arg)632 dofkusers_walker(const ldi_usage_t *ldi_usage, void *arg)
633 {
634 dofkusers_arg_t *dofkusers_arg = (dofkusers_arg_t *)arg;
635
636 vnode_t *fvp = dofkusers_arg->fvp;
637 int flags = dofkusers_arg->flags;
638 int *error = dofkusers_arg->error;
639 fu_data_t *fu_data = dofkusers_arg->fu_data;
640
641 modid_t modid;
642 minor_t minor;
643 int instance;
644 int dip_usage = (flags & F_DEVINFO);
645
646 ASSERT(*error == 0);
647 ASSERT(vn_matchops(fvp, spec_getvnodeops()));
648
649 /*
650 * check if the dev_t of the target device matches the dev_t
651 * of the device we're trying to find usage info for.
652 */
653 if (fvp->v_rdev != ldi_usage->tgt_devt) {
654
655 /*
656 * if the dev_ts don't match and we're not trying
657 * to find usage information for device instances
658 * then return
659 */
660 if (!dip_usage)
661 return (LDI_USAGE_CONTINUE);
662
663
664 /*
665 * we're trying to find usage information for an
666 * device instance instead of just a minor node.
667 *
668 * check if the dip for the target device matches the
669 * dip of the device we're trying to find usage info for.
670 */
671 if (VTOCS(fvp)->s_dip != ldi_usage->tgt_dip)
672 return (LDI_USAGE_CONTINUE);
673 }
674
675 if (fu_data->fud_user_count >= fu_data->fud_user_max) {
676 *error = E2BIG;
677 return (LDI_USAGE_TERMINATE);
678 }
679
680 /* get the device vnode user information */
681 modid = ldi_usage->src_modid;
682 ASSERT(modid != -1);
683
684 minor = instance = -1;
685 if (ldi_usage->src_dip != NULL) {
686 instance = DEVI(ldi_usage->src_dip)->devi_instance;
687 }
688 if (ldi_usage->src_devt != DDI_DEV_T_NONE) {
689 minor = getminor(ldi_usage->src_devt);
690 }
691
692 /* set the device vnode user information */
693 fu_data->fud_user[fu_data->fud_user_count].fu_flags = F_KERNEL;
694 fu_data->fud_user[fu_data->fud_user_count].fu_modid = modid;
695 fu_data->fud_user[fu_data->fud_user_count].fu_instance = instance;
696 fu_data->fud_user[fu_data->fud_user_count].fu_minor = minor;
697
698 fu_data->fud_user_count++;
699
700 return (LDI_USAGE_CONTINUE);
701 }
702
703 int
f_user_cmp(const void * arg1,const void * arg2)704 f_user_cmp(const void *arg1, const void *arg2)
705 {
706 f_user_t *f_user1 = (f_user_t *)arg1;
707 f_user_t *f_user2 = (f_user_t *)arg2;
708
709 /*
710 * we should only be called for f_user_t entires that represent
711 * a kernel file consumer
712 */
713 ASSERT(f_user1->fu_flags & F_KERNEL);
714 ASSERT(f_user2->fu_flags & F_KERNEL);
715
716 if (f_user1->fu_modid != f_user2->fu_modid)
717 return ((f_user1->fu_modid < f_user2->fu_modid) ? -1 : 1);
718
719 if (f_user1->fu_instance != f_user2->fu_instance)
720 return ((f_user1->fu_instance < f_user2->fu_instance) ? -1 : 1);
721
722 if (f_user1->fu_minor != f_user2->fu_minor)
723 return ((f_user1->fu_minor < f_user2->fu_minor) ? -1 : 1);
724
725 return (0);
726 }
727
728 static fu_data_t *
dofkusers(vnode_t * fvp,int flags,int * error)729 dofkusers(vnode_t *fvp, int flags, int *error)
730 {
731 dofkusers_arg_t dofkusers_arg;
732 fu_data_t *fu_data;
733 int user_max, i;
734
735 /*
736 * we only keep track of kernel device consumers, so if the
737 * target vnode isn't a device then there's nothing to do here
738 */
739 if (!vn_matchops(fvp, spec_getvnodeops()))
740 return (NULL);
741
742 /* allocate the data structure to return our results in */
743 user_max = ldi_usage_count();
744 fu_data = kmem_alloc(fu_data_size(user_max), KM_SLEEP);
745 fu_data->fud_user_max = user_max;
746 fu_data->fud_user_count = 0;
747
748 /* invoke the callback to collect device usage information */
749 dofkusers_arg.fvp = fvp;
750 dofkusers_arg.flags = flags;
751 dofkusers_arg.error = error;
752 dofkusers_arg.fu_data = fu_data;
753 ldi_usage_walker(&dofkusers_arg, dofkusers_walker);
754
755 /* check for errors */
756 if (*error != 0)
757 return (fu_data);
758
759 /* if there aren't any file consumers then return */
760 if (fu_data->fud_user_count == 0)
761 return (fu_data);
762
763 /*
764 * since we ignore the spec_type of the target we're trying to
765 * access it's possible that we could have duplicates entries in
766 * the list of consumers.
767 *
768 * we don't want to check for duplicate in the callback because
769 * we're holding locks in the ldi when the callback is invoked.
770 *
771 * so here we need to go through the array of file consumers
772 * and remove duplicate entries.
773 */
774
775 /* first sort the array of file consumers */
776 qsort((caddr_t)fu_data->fud_user, fu_data->fud_user_count,
777 sizeof (f_user_t), f_user_cmp);
778
779 /* then remove any duplicate entires */
780 i = 1;
781 while (i < fu_data->fud_user_count) {
782
783 if (f_user_cmp(&fu_data->fud_user[i],
784 &fu_data->fud_user[i - 1]) != 0) {
785 /*
786 * the current element is unique, move onto
787 * the next one
788 */
789 i++;
790 continue;
791 }
792
793 /*
794 * this entry is a duplicate so if it's not the last
795 * entry in the array then remove it.
796 */
797 fu_data->fud_user_count--;
798 if (i == fu_data->fud_user_count)
799 break;
800
801 bcopy(&fu_data->fud_user[i + 1], &fu_data->fud_user[i],
802 sizeof (f_user_t) * (fu_data->fud_user_count - i));
803 }
804
805 return (fu_data);
806 }
807
808 /*
809 * Determine the ways in which processes and the kernel are using a named
810 * file or mounted file system (path). Normally return 0. In case of an
811 * error appropriate errno will be returned.
812 *
813 * Upon success, uts_fusers will also copyout the file usage information
814 * in the form of an array of f_user_t's that are contained within an
815 * fu_data_t pointed to by userbp.
816 */
817 static int
uts_fusers(char * path,int flags,intptr_t userbp)818 uts_fusers(char *path, int flags, intptr_t userbp)
819 {
820 fu_data_t *fu_data = NULL, *fuk_data = NULL;
821 fu_data_t fu_header;
822 vnode_t *fvp = NULL;
823 size_t bcount;
824 int error = 0;
825 int total_max, total_out;
826 int contained = (flags & F_CONTAINED);
827 int dip_usage = (flags & F_DEVINFO);
828 int fvp_isdev;
829
830
831 /* figure out how man f_user_t's we can safetly copy out */
832 if (copyin((const void *)userbp, &total_max, sizeof (total_max)))
833 return (EFAULT);
834
835 /*
836 * check if we only want a count of how many kernel device
837 * consumers exist
838 */
839 if (flags & F_KINFO_COUNT) {
840 fu_header.fud_user_max = total_max;
841 fu_header.fud_user_count = ldi_usage_count();
842 bcount = fu_data_size(0);
843 if (copyout(&fu_header, (void *)userbp, bcount))
844 return (EFAULT);
845 return (0);
846 }
847
848 /* get the vnode for the file we want to look up usage for */
849 error = lookupname(path, UIO_USERSPACE, FOLLOW, NULLVPP, &fvp);
850 if (error != 0)
851 return (error);
852 ASSERT(fvp);
853 fvp_isdev = vn_matchops(fvp, spec_getvnodeops());
854
855 /*
856 * if we want to report usage for all files contained within a
857 * file system then the target file better correspond to the
858 * root node of a mounted file system, or the root of a zone.
859 */
860 if (contained && !(fvp->v_flag & VROOT) &&
861 fvp != curproc->p_zone->zone_rootvp) {
862 error = EINVAL;
863 goto out;
864 }
865
866 /*
867 * if we want to report usage for all files contained within a
868 * file system then the target file better not be a device.
869 */
870 if (contained && fvp_isdev) {
871 error = EINVAL;
872 goto out;
873 }
874
875 /*
876 * if we want to report usage for a device instance then the
877 * target file better corrospond to a device
878 */
879 if (dip_usage && !fvp_isdev) {
880 error = EINVAL;
881 goto out;
882 }
883
884 /*
885 * if the target vnode isn't a device and it has a reference count
886 * of one then no one else is going to have it open so we don't
887 * have any work to do.
888 */
889 if (!fvp_isdev && (fvp->v_count == 1)) {
890 goto out;
891 }
892
893 /* look up usage information for this vnode */
894 fu_data = dofusers(fvp, flags);
895 fuk_data = dofkusers(fvp, flags, &error);
896 if (error != 0)
897 goto out;
898
899 /* get a count of the number of f_user_t's we need to copy out */
900 total_out = 0;
901 if (fu_data)
902 total_out += fu_data->fud_user_count;
903 if (fuk_data)
904 total_out += fuk_data->fud_user_count;
905
906 /* check if there is enough space to copyout all results */
907 if (total_out > total_max) {
908 error = E2BIG;
909 goto out;
910 }
911
912 /* copyout file usage info counts */
913 fu_header.fud_user_max = total_max;
914 fu_header.fud_user_count = total_out;
915 bcount = fu_data_size(0);
916 if (copyout(&fu_header, (void *)userbp, bcount)) {
917 error = EFAULT;
918 goto out;
919 }
920
921 /* copyout userland process file usage info */
922 if ((fu_data != NULL) && (fu_data->fud_user_count > 0)) {
923 userbp += bcount;
924 bcount = fu_data->fud_user_count * sizeof (f_user_t);
925 if (copyout(fu_data->fud_user, (void *)userbp, bcount)) {
926 error = EFAULT;
927 goto out;
928 }
929 }
930
931 /* copyout kernel file usage info */
932 if ((fuk_data != NULL) && (fuk_data->fud_user_count > 0)) {
933 userbp += bcount;
934 bcount = fuk_data->fud_user_count * sizeof (f_user_t);
935 if (copyout(fuk_data->fud_user, (void *)userbp, bcount)) {
936 error = EFAULT;
937 goto out;
938 }
939 }
940
941 out:
942 /* release the vnode that we were looking up usage for */
943 VN_RELE(fvp);
944
945 /* release any allocated memory */
946 if (fu_data)
947 kmem_free(fu_data, fu_data_size(fu_data->fud_user_max));
948 if (fuk_data)
949 kmem_free(fuk_data, fu_data_size(fuk_data->fud_user_max));
950
951 return (error);
952 }
953